Audio Transducer Systems, Methods, and Devices

Abstract

To provide an alternative audio transducer device that works somewhat to address some of the shortcomings of existing technologies, a manufacturing method for the same, and a personal audio device.SOLUTION: An audio transducer A100 includes a diaphragm A101, a diaphragm suspension, and a transducer base structure. The diaphragm suspension includes multiple hinge mounts A107a, A107b. The transducer base structure includes a body A110 and a conductive coil A106 of a conversion mechanism. The diaphragm suspension rotatably mounts the diaphragm A101 to the transducer base structure. The diaphragm suspension is made of soft material and / or damping material. The position of the rotational axis of the diaphragm A101 is determined on the basis of a nodal axis of the diaphragm A101. The conversion mechanism of the audio transducer converts sound in cooperation with the moving diaphragm A101 and includes a design in which a magnet moves or a design in which a coil moves.SELECTED DRAWING: Figure 1F

Description

[Technical Field]

[0001] The present invention relates to audio transducers, such as those used in loudspeakers and microphones, and related devices or methods. [Background technology]

[0002] A loudspeaker driver is a type of audio transducer that generates sound by vibrating a diaphragm using an actuation mechanism, which can be an electromagnetic, electrostatic, piezoelectric, or any other suitable movable assembly known in the art. Drivers are typically contained within a housing. In conventional drivers, the diaphragm is a flexible membrane component linearly coupled to a rigid housing. Loudspeaker drivers therefore form a resonant system in which the diaphragm is susceptible to unwanted mechanical resonance (also known as diaphragm breakup) at certain frequencies during operation. This affects the performance and sound quality of the driver.

[0003] Rotary action loudspeakers operate by rotating a diaphragm to generate sound. Recent developments in loudspeaker technology have benefited from this approach, improving performance and sound quality over traditional linear driver technology. Such developments are exemplified, for example, in PCT publication WO2017 / 046716, where a stiffness approach to multiple driver aspects, including, for example, the diaphragm and diaphragm suspension, is used to push unwanted resonances to frequencies that are either about beyond the listener's hearing range or about beyond the frequency range of the driver's intended operation.

[0004] Given that loudspeaker design depends on factors including performance and intended use, a need continues to exist for alternative designs that may be better suited to particular applications.

[0005] It is an object of the present invention to provide an alternative audio transducer device or method of manufacture that goes some way to addressing some of the shortcomings of existing technology, or at least to provide the public with a useful choice. Summary of the Invention

[0006] Device Aspects In some aspects, the present invention generally comprises: A diaphragm and a transducer base structure; a diaphragm suspension system configured to rotatably mount the diaphragm relative to a transducer base structure, the diaphragm suspension system being arranged such that a primary axis of rotation of the diaphragm relative to the transducer base structure is disposed in a plane that is substantially perpendicular to a coronal plane of the diaphragm and that contains a predetermined nodal axis of the diaphragm; a transducer mechanism operably coupled to the diaphragm for converting between audio signals and sound pressure; It can be said that the audio transducer is composed of an audio transducer having:

[0007] In some aspects, the present invention generally comprises: A diaphragm and a transducer base structure; a diaphragm suspension system configured to rotatably mount a diaphragm relative to a transducer base structure, the diaphragm suspension system being arranged such that a primary axis of rotation of the diaphragm relative to the transducer base structure and a center of mass axis of the diaphragm are substantially coaxial; a transducer mechanism operably coupled to the diaphragm for converting between audio signals and sound pressure; It can be said that the audio transducer is composed of an audio transducer having:

[0008] In some aspects, the present invention generally comprises: a diaphragm structure including a plurality of diaphragms; a transducer base structure; a diaphragm suspension configured to rotatably mount the diaphragm structure relative to the transducer base structure such that the diaphragm structure can rotate about an axis of rotation relative to the transducer base structure; a transduction mechanism operably coupled to the diaphragm structure for converting between audio signals and sound pressure; It can be said that the audio transducer is composed of an audio transducer having:

[0009] In some aspects, the present invention generally comprises: A diaphragm and a transducer base structure; a diaphragm suspension configured to rotatably mount a diaphragm relative to the transducer base structure such that the diaphragm structure can rotate about an axis of rotation relative to the transducer base structure, the diaphragm suspension comprising at least one hinge; a transduction mechanism operably coupled to the diaphragm structure for converting between audio signals and sound pressure; It can be said that the audio transducer is composed of an audio transducer having:

[0010] In some aspects, the present invention generally comprises: A diaphragm and a transducer base structure; a diaphragm suspension configured to mount the diaphragm to the transducer base structure such that the diaphragm can rotate relative to the transducer base structure; a transducer for converting between audio signals and sound pressure, the transducer comprising a magnet or magnetic assembly coupled to the diaphragm and movable with the diaphragm during operation; It can be said that the audio transducer is composed of an audio transducer having:

[0011] Device Embodiments Unless otherwise stated, the following embodiments may apply to any one or more of the aspects described above, and features of any two or more embodiments may be combined with any aspect.

[0012] In some embodiments, the audio transducer may comprise a single diaphragm. In the case of a rotary motion transducer, the single diaphragm may extend radially in a single direction from the axis of rotation.

[0013] In some embodiments, the audio transducer may comprise a diaphragm structure including multiple diaphragms.

[0014] In some embodiments, the diaphragms may extend from a central location at an angle relative to one another. In the case of a rotary motion transducer, the diaphragms may be spaced radially around the axis of rotation, for example. The diaphragms may be uniformly spaced radially. For example, a pair of diaphragms may be spaced 180 degrees apart.

[0015] In some embodiments, the multiple diaphragms are substantially rigidly connected to one another.

[0016] The following embodiments may relate to single diaphragm transducer embodiments or multiple diaphragm transducer embodiments.

[0017] In some embodiments, each diaphragm remains substantially stiff when in use.

[0018] In some embodiments, each diaphragm may comprise a diaphragm body formed from a composite material. The diaphragm body may comprise a three-dimensionally varying interconnected structure. The diaphragm body may comprise a substantially low-density matrix. The diaphragm body may be formed from a low-density foam material, such as polystyrene foam.

[0019] In some embodiments, each diaphragm comprises a substantially thick diaphragm body. The maximum thickness of the diaphragm body may be greater than 12% or 15% of the length of the diaphragm body. The maximum thickness of the diaphragm body may be greater than 20% of the length of the diaphragm body. The maximum thickness of the diaphragm body may be greater than 9% or 11% of the maximum dimension of the diaphragm body, such as the diagonal length. The maximum thickness of the diaphragm body may be greater than 14% of the maximum dimension of the diaphragm body, such as the diagonal length.

[0020] In some embodiments, the length of the diaphragm from the axis of rotation to the opposite end may be less than about 6 times, or less than 4 times, or less than 3 times the axial width of the diaphragm or diaphragm structure.

[0021] In some embodiments, the mass of each diaphragm may vary along its length. In some embodiments, each diaphragm may have a relatively smaller mass per unit area in a region of the diaphragm distal to its center of mass than in a region of the diaphragm proximal to its center of mass. In some embodiments, when the diaphragm is configured to rotate relative to the transducer base structure, each diaphragm may have a smaller mass per unit area in a region of the diaphragm distal to the axis of rotation than in a region of the diaphragm proximal to the axis of rotation. In some embodiments, each diaphragm may have a relatively smaller mass per unit area in a region proximal to one end of the diaphragm than in a region proximal to the opposite end.

[0022] In some embodiments, the thickness of the diaphragm in areas of relatively low mass may be less than in areas of relatively high mass.

[0023] In some embodiments, each diaphragm may be substantially wedge-shaped.

[0024] In some embodiments, the thickness of each diaphragm may be tapered along its length. The thickness of each diaphragm may be tapered substantially smoothly along its length. The thickness of the diaphragm may be tapered from the axis of rotation to the distal end, or from the center of mass to the distal end, in the case of a rotary diaphragm. The thickness of the diaphragm may be tapered from the central region to the distal end. The thickness of the diaphragm may be substantially uniform from the axis of rotation to the proximal end, or from the proximal end to the center of mass, in the case of a rotary diaphragm. Alternatively, the thickness of the diaphragm may be tapered from the central region to the proximal end. This tapered thickness may be tapered from the central region to the proximal end. The central region may be located approximately 15-50% of the longitudinal length of the diaphragm between the proximal end and the distal end. The central region may be located approximately 20% of the longitudinal length of the diaphragm between the proximal end and the distal end.

[0025] Each taper may be stepped or continuous, and each taper may be linear or curved.

[0026] In some embodiments, the absolute value of the angle of the radiating plane of the diaphragm between the central region and the proximal end relative to the coronal plane of the diaphragm is less than the absolute value of the angle of the radiating plane between the central region and the distal end.

[0027] In some embodiments, the profile of at least one major surface of each diaphragm is substantially convex along the longitudinal length of the diaphragm and / or along a sagittal plane of the diaphragm. In some embodiments, the profile of each major surface of each diaphragm is substantially convex along the longitudinal length of the diaphragm and / or along a sagittal plane of the diaphragm.

[0028] In some embodiments, each diaphragm may comprise a diaphragm body having one or more primary radiating surfaces, and a normal stress stiffener coupled to the body, the normal stress stiffener coupled adjacent to at least one of the primary radiating surfaces to resist compressive-tensile stresses experienced at or adjacent to the surfaces of the body during operation. There may be two opposing radiating surfaces.

[0029] In some embodiments, the normal stress stiffener may have a relatively smaller mass per unit area in a region of the diaphragm distal to the center of mass than in a region of the diaphragm proximal to the center of mass of the diaphragm. In some embodiments, when the diaphragm is configured to rotate relative to the transducer base structure, the normal stress stiffener may have a relatively smaller mass per unit area in a region of the diaphragm distal to the axis of rotation than in a region of the diaphragm proximal to the axis of rotation of the diaphragm. In some embodiments, the normal stress stiffener may have a relatively smaller mass per unit area in a region proximal to one end of the diaphragm than in a region proximal to the opposite end.

[0030] In some embodiments, regions of relatively low mass of normal stress stiffeners may have recesses or may be free of normal stress stiffeners. In some embodiments, regions of relatively low mass of normal stress stiffeners may have a reduced or tapered thickness, or a narrower or tapered width, or both.

[0031] In some embodiments, the surface area of ​​the regions of the vertical stress stiffener and / or diaphragm where the mass is relatively large is about 30-70% of the surface area of ​​the major surface, and the surface area of ​​the regions of the vertical stress stiffener and / or diaphragm where the mass is relatively small is about 30-70% of the surface area of ​​the major surface.

[0032] In some embodiments, the region of relatively low mass of the normal stress stiffener and / or the diaphragm may be located within about 20% of the length of the diaphragm from the end of the diaphragm distal to the center of mass, or in the case of a rotating diaphragm, distal to the axis of rotation.

[0033] In some embodiments, each diaphragm may comprise a diaphragm body having one or more primary radiating surfaces, and at least one internal stiffening member embedded within the body and oriented at an angle relative to at least one of said primary surfaces to resist and / or substantially mitigate shear deformations experienced by the body during operation. There may be multiple internal stiffening members.

[0034] In some embodiments, the length of each diaphragm from the center of mass to the distal end, or from one end to the opposite end, or in the case of a rotating diaphragm, from the axis of rotation to the opposite end, may be about 20% longer than the width of the diaphragm.

[0035] In some embodiments, the length of each diaphragm from the axis of rotation to its opposite end may be less than about 6 times, less than 4 times, or less than 3 times the axial width of the diaphragm assembly.

[0036] In some embodiments, each diaphragm may comprise a diaphragm base structure rigidly coupled to the diaphragm body. The diaphragm base structure may be located at or proximal to the axis. The diaphragm base structure may comprise a majority of the mass of the diaphragm assembly. The diaphragm base structure may structurally act as a rigid shaft. The diaphragm base structure may include the diaphragm body or may rigidly connect the diaphragm body to the diaphragm suspension. The diaphragm may be rigidly connected proximately to the diaphragm suspension via the diaphragm base structure. The diaphragm base structure may comprise a translation mechanism. The diaphragm base structure may rigidly connect the diaphragm body to the translation mechanism. The diaphragm may be rigidly connected proximately to the translation mechanism via the diaphragm base structure.

[0037] In some embodiments, the diaphragm base structure may be rigidly connected to the normal stress stiffeners of each diaphragm.

[0038] In some embodiments, the diaphragm base structure may be constructed from one or more substantially planar pieces.

[0039] In some embodiments, the diaphragm base structure may be rigidly coupled to the diaphragm body via one or more rigid components that are sufficiently straight and / or sufficiently supported and / or sufficiently thick that bending deformation of the rigid component(s) is substantially negligible during operation.

[0040] In some embodiments, the diaphragm base structure may be rigidly coupled to the diaphragm body only via components having a relatively high Young's modulus, preferably greater than about 0.5 GPa, more preferably greater than about 2 GPa, and most preferably greater than about 4 GPa.

[0041] In some embodiments, each diaphragm body is rigidly coupled to an associated diaphragm base structure.

[0042] In some embodiments, the diaphragm base structure comprises a relatively stiff material having a Young's modulus of at least about 8 GPa, or at least about 20 GPa. In some embodiments, each diaphragm is rigidly connected to a diaphragm suspension. In some embodiments, each diaphragm is rigidly connected to a transduction mechanism.

[0043] In some embodiments, the audio transducer further comprises a structure immediately surrounding each diaphragm. A single structure, such as a housing, may surround all of the diaphragms and / or the remainder of the transducer, or separate structures may surround each diaphragm individually.

[0044] In some embodiments, each diaphragm comprises a periphery that is at least partially free of physical connection with the interior of the immediately surrounding structure associated with the diaphragm.

[0045] In some embodiments, the diaphragm may include one or more peripheral regions that are not physically connected to the interior of the periphery, and the periphery may have few physical connections such that the one or more peripheral regions constitute at least 20% of the length or perimeter of the periphery. In some embodiments, the periphery may be substantially free of physical connections such that the one or more peripheral regions may constitute at least 50% of the length or perimeter of the periphery. In some embodiments, the one or more peripheral regions may constitute at least 80% of the length or perimeter of the periphery.

[0046] In some embodiments, all areas of the diaphragm's periphery that move a significant distance (relative to other areas) during normal operation may have little or no physical connection to the interior of the surrounding structure.

[0047] In some embodiments, all areas of the periphery of the diaphragm distal to the location of the center of mass of the diaphragm can have little to no physical connection to the interior of the surrounding structure.

[0048] In some embodiments, one or more regions of the diaphragm's periphery that are not physically connected to the interior of the periphery may be separated from the housing by an air gap. A relatively narrow air gap may separate the interior of the periphery structure from one or more peripheral regions of the diaphragm, such that the width of the air gap, defined by the distance between each peripheral region and the periphery structure, may be less than about 1 / 10, or less than about 1 / 20, or less than about 1 / 40 of the length of the diaphragm.

[0049] In some embodiments, a relatively narrow air gap may separate the interior of the surrounding structure from one or more peripheral regions of the diaphragm, such that the width of the air gap defined by the distance between each peripheral region and the surrounding structure is less than about 1 mm, less than about 0.8 mm, or less than about 0.5 mm.

[0050] In some embodiments, the surrounding structure is substantially tightly fitted around the periphery of the diaphragm over substantially the entire range of movement of the diaphragm during operation, but is physically separated, so that the surrounding structure is effectively sealed.

[0051] In some embodiments, the combination of a snug fit with the perimeter and the use of a housing and / or baffle to surround the transducer effectively separates the air adjacent to the primary radiating surface of the diaphragm, which generates positive air pressure in certain rotational directions, from the air adjacent to the opposite primary radiating surface of the diaphragm.

[0052] In some embodiments, each surrounding structure may include a reinforced region facing the end of the associated diaphragm that is distal from the axis of rotation. The reinforced region may face the end of the diaphragm that is configured to move the greatest distance during operation and may extend along the entire range of movement of the end during operation. The reinforced region may be stiffer than adjacent regions of the surrounding structure. In the case of a rotating diaphragm, the reinforced region may be provided in a curved wall of the surrounding structure that is positioned immediately adjacent to the end of the associated diaphragm.

[0053] In some embodiments, the reinforcement is in a direction substantially parallel to the axis across the entire width of the end portion.

[0054] In some embodiments, the reinforced region may be thicker than adjacent regions of the surrounding structure.

[0055] In some embodiments, the reinforced region may comprise one or more reinforcing ribs.

[0056] In some embodiments, the reinforced regions may comprise a material that is relatively stiffer than the material of the adjacent regions.

[0057] In some embodiments, the surrounding structure may comprise a protective material, such as velvet or silicone, on the inner wall adjacent the periphery of the diaphragm.

[0058] In some embodiments, the surrounding structure may comprise an elastomeric protective material, such as silicone or rubber, formed into hollow compliant shapes, e.g., ribs or foam, on the inner wall adjacent the periphery of the diaphragm.

[0059] In some embodiments, the surrounding structure may comprise one or more stoppers on the inner wall adjacent to one or both emitting surfaces of the associated diaphragm to prevent the emitting surfaces from contacting and colliding with the inner wall in use.

[0060] In some embodiments, the stop prevents excessive displacement of the diaphragm relative to the housing beyond the leading edge of the diaphragm, perpendicular to the axis of rotation and towards the leading edge of the diaphragm. The maximum displacement in this direction may be about 0.5 mm, more preferably 0.35 mm, and most preferably 0.2 mm.

[0061] In some embodiments, the opening in the surround structure adjacent the primary radiating surface of the diaphragm is at the front of the enclosure and faces towards the listener.

[0062] In some embodiments, the coronal surface of the diaphragm within the surround faces the listener when at the maximum angle of motion and displaced toward the listener.

[0063] In some embodiments, each diaphragm may be substantially symmetrical about the sagittal plane of the diaphragm.

[0064] In some embodiments, each diaphragm may be substantially symmetrical about a sagittal plane of the diaphragm that is substantially perpendicular to the axis of rotation.

[0065] In some embodiments, the audio transducer may comprise a diaphragm assembly including a diaphragm and a diaphragm-side transduction component of a transduction mechanism, the diaphragm-side transduction component configured to transfer forces to or from the diaphragm during operation, and the diaphragm assembly being substantially symmetrical about a sagittal plane of the diaphragm.

[0066] In some embodiments, each diaphragm does not have an internal or external position sensor.

[0067] In some embodiments, the audio transducer may comprise a diaphragm suspension configured to rotatably couple a diaphragm or multi-diaphragm diaphragm structure to a transducer base structure.

[0068] In some embodiments, the diaphragm suspension may allow rotation of the diaphragm about the axis of rotation to provide angular motion in the range of about 10 degrees on either side of the axis, or about 15 degrees on either side of the axis, or about 20 degrees on either side of the axis.

[0069] In some embodiments, the diaphragm suspension may include at least one hinge mount, each hinge mount may be coupled to the diaphragm or diaphragm structure and to the transducer base structure.

[0070] In some embodiments, the diaphragm suspension may include multiple hinge mounts.

[0071] In some embodiments, the diaphragm suspension may comprise a pair of hinge mounts coupled to the diaphragm or diaphragm structure.

[0072] In some embodiments, the diaphragm suspension may comprise a pair of hinge mounts coupled on either side of the diaphragm between the diaphragm and the transducer base structure.

[0073] In some embodiments, each hinge mount may be substantially coaxial with the nodal axis and / or center of mass axis of the diaphragm.

[0074] In some embodiments, a pair of hinge mounts may be joined on opposite sides of the diaphragm.

[0075] In some embodiments, the diaphragm suspension may comprise at least two hinge mounts rotatably coupling the diaphragm to the transducer base structure, the at least two hinge mounts being positioned on either side of a mid-sagittal plane of the diaphragm or diaphragm structure diaphragm substantially perpendicular to the axis of rotation, each hinge mount being positioned at a distance from the mid-sagittal plane at least 0.2 times the maximum width of the diaphragm.

[0076] In some embodiments, the diaphragm suspension may comprise at least two hinge mounts rotatably coupling the diaphragm to the transducer base structure, the at least two hinge mounts being positioned on opposite sides of a mid-sagittal plane of the diaphragm or diaphragm structure diaphragm substantially perpendicular to the axis of rotation, each hinge mount being positioned at a distance from the mid-sagittal plane that is less than about 0.47, 0.45, or 0.42 times the maximum width of the diaphragm.

[0077] Each hinge mount may be located outside the diaphragm-side transduction component of the translation mechanism.

[0078] In some embodiments, the diaphragm suspension may be arranged such that the axis of rotation of the diaphragm or diaphragm structure relative to the transducer base structure is located in a plane that is substantially perpendicular to the coronal plane of the diaphragm or diaphragm structure and that contains a predetermined nodal axis of the diaphragm or diaphragm structure.

[0079] In some embodiments, the nodal axis may be predetermined.

[0080] In some embodiments, the rotational axis and the nodal axis are substantially parallel.

[0081] In some embodiments, the rotational axis and the nodal axis are substantially coaxial.

[0082] In some embodiments, the diaphragm suspension may be arranged so that the axis of rotation of the diaphragm or diaphragm structure relative to the transducer base structure and the central axis of mass of the diaphragm or diaphragm structure are substantially parallel.

[0083] In some embodiments, the diaphragm suspension may be arranged so that the axis of rotation of the diaphragm or diaphragm structure relative to the transducer base structure and the center of mass axis of the diaphragm or diaphragm structure are substantially coaxial.

[0084] In some embodiments, the nodal axis can be determined by identifying the axis of rotation of the diaphragm in a substantially unsupported actuated state (where the diaphragm is not coupled to the diaphragm suspension system and is indicative of the movement forces generated by the translation mechanism).

[0085] In some embodiments, the nodal axis may be predetermined using any one of the following methods. Conducting a computer simulation to determine where the axis of rotation of a computer model of an audio transducer, excluding the diaphragm suspension system, is when the model's transduction mechanism is actuated by a simulated audio signal Activating the conversion mechanism of a physical model of an audio transducer in which the diaphragm of the physical model is virtually unsupported, and determining the rotation axis of the diaphragm

[0086] In some embodiments, actuating the translation mechanism may include actuating the mechanism to vibrate the diaphragm within a mass-controlled region of the diaphragm. Actuating the translation mechanism may include actuating the mechanism to vibrate the diaphragm within the mass-controlled region of the diaphragm about a resonant mode that includes a strong component of diaphragm translational motion in a direction perpendicular to the coronal plane of the diaphragm.

[0087] In some embodiments, the predetermined nodal axis can be determined experimentally by mounting the diaphragm very lightly, for example with a heavy component resting on soft foam, so that the diaphragm is effectively unsupported, applying a vibratory force and / or torque in substantially the same direction as it will be in use, and then measuring the nodes directly, for example with a lightweight accelerometer, or with a laser Doppler vibrometer, or with a proximity sensor. Alternatively, or additionally, the predetermined nodal axis can be determined by operating the transducer at a frequency at which it becomes effectively unsupported relative to the transducer base structure.

[0088] In some embodiments, the diaphragm suspension may flexibly mount the diaphragm or diaphragm structure to the transducer base structure. Each hinge mount may provide rotational compliance about at least one axis.

[0089] In some embodiments, the diaphragm suspension may include at least one mount formed from an amorphous metal alloy such as Liquidmetal or Vitreloy.

[0090] In some embodiments, there are several resonant modes involving diaphragm motion where the diaphragm structure remains substantially rigid, like the driver base structure, and compliance is primarily in the diaphragm suspension. Of these modes, the mode involving rotation about the diaphragm's major axis preferably has the lowest frequency, preferably below 0.75, and more preferably below 0.5, of the frequency of the next highest frequency mode.

[0091] In some embodiments, the flexible hinge mounts may together provide a primary resistance to translational displacement of the vibrating mass relative to the transducer base structure in use.

[0092] In some embodiments, the flexible hinge mounts may together, in use, provide a primary resistance to translational displacement of the vibrating mass relative to the transducer base structure along at least two substantially orthogonal axes.

[0093] In some embodiments, the flexible hinge mounts may together, in use, provide a primary resistance to translational displacement of the vibrating mass relative to the transducer base structure along at least three substantially orthogonal axes.

[0094] The flexible hinge mount provides primary compliance for rotation of the diaphragm relative to the transducer base structure about the axis of rotation.

[0095] In some embodiments, the diaphragm suspension may include at least one mount formed from a substantially soft material having an average Young's modulus of less than about 8 gigapascals (GPa). The at least one flexible mount may be formed from a substantially soft material having an average Young's modulus of less than about 4 gigapascals (GPa). The at least one flexible mount may be formed from a substantially soft material having an average Young's modulus of less than about 2 gigapascals (GPa). The at least one flexible mount may be formed from a substantially soft material having an average Young's modulus of less than about 1 gigapascal (GPa).

[0096] In some embodiments, the diaphragm suspension may include at least one hinge mount having a sufficiently low Young's modulus such that the diaphragm fundamental resonant frequency is less than about 100 Hertz. The fundamental resonant frequency may be less than about 70 Hertz. The fundamental resonant frequency may be less than about 50 Hertz.

[0097] In some embodiments, each substantially flexible hinge mount may be substantially compliant in a translational direction such that the hinge mount can deform substantially linearly along at least one axis. Each substantially flexible hinge mount may be substantially compliant in a translational direction such that the hinge mount can deform substantially linearly along at least two orthogonal axes. Each substantially flexible hinge mount may be substantially compliant in a translational direction such that the hinge mount can deform substantially linearly along three orthogonal axes.

[0098] In some embodiments, the diaphragm suspension may include at least one mount formed from an elastomer or soft plastic material, which may be a urethane, such as a thermoset urethane, or a silicone plastic material, or nitrile rubber (NBR).

[0099] In some embodiments, each mount may be formed from a mold, such as an injection mold. In some embodiments, each flexible mount is a primary hinge support.

[0100] In some embodiments, each mount may be formed from a material having a Young's modulus in compression of less than 1 GPa, more preferably less than 0.5 GPa, more preferably even less than 0.1 GPa, and most preferably less than 0.05 GPa. Preferably, the material also has a Young's modulus greater than 0.003 GPa, more preferably greater than 0.005 GPa, more preferably even greater than 0.0065 GPa, and most preferably greater than 0.008 GPa. In some embodiments, the material may have a durometer less than 90, more preferably less than 85, and most preferably less than 75 on the Shore A scale. In some embodiments, the material may have a durometer greater than 30, more preferably greater than 40, and most preferably greater than 55 on the Shore A scale.

[0101] In some embodiments, each flexible mount may comprise a bushing rigidly coupled to the diaphragm at one end and to the transducer base structure at the opposite end. The bushing may be substantially hollow. The bushing may comprise a plurality of radially spaced longitudinal channels. The bushing may comprise a plurality of discrete radially extending internal spokes. Each bushing may be rigidly coupled to a respective pin extending laterally from the diaphragm or transducer base structure along an axis substantially coaxial with the nodal axis and / or center-of-mass axis of the diaphragm. Each flexible bushing is configured to mate with a recess on a corresponding side of the transducer base structure or diaphragm. The shape of the inner periphery of each recess may correspond to the outer periphery of the corresponding bushing.

[0102] In some embodiments, each hinge mount may include a pin rigidly connected to either the diaphragm or the transducer base structure and extending substantially coaxially with the axis of rotation, with the soft, flexible material of the hinge mount in intimate contact with the pin, and the flexible material may be connected to a portion of the other of the diaphragm or the transducer base structure that extends around the pin.

[0103] In some embodiments, each hinge mount may comprise an elongated flexible element, one end of which may be connected to the diaphragm and the other end of which may be connected to the transducer base structure, and the minimum length through the flexible material from the diaphragm to the transducer base structure may be greater than 1.5 times, more preferably greater than 2 times, and most preferably greater than 2.5 times the minimum thickness across the elongated element in a direction perpendicular to the length.

[0104] In some embodiments, the soft hinge comprises a torsion element disposed on an axis, the diaphragm assembly may be connected at one end of this element and the driver base may be connected at the other end, and one or both connections may be disposed substantially on the axis.

[0105] In some embodiments, each hinge mount may comprise an elongated flexible hinge element. One end may be connected to the diaphragm, and the other end may be connected to the transducer base structure. The shortest length through the flexible hinge element from the diaphragm to the transducer base structure may be greater than 1.5 times, more preferably greater than 2 times, and most preferably greater than 2.5 times the minimum thickness across the elongated element in a direction perpendicular to the length. The length through the flexible material is preferably substantially straight. In some embodiments, the hinge may comprise separate elongated flexible elements oriented in significantly different directions, which can provide strong support against translational motion because each element can provide little compliance along its length. The connection point between the diaphragm and the transducer base structure may have a thicker profile than the center of each flexible hinge element. Each flexible element may be substantially planar and oriented substantially parallel to the axis of rotation.

[0106] In some embodiments, each hinge mount may be substantially damped.

[0107] In some embodiments, each hinge mount may be formed from a material having a material loss factor greater than 0.005 at 30 degrees Celsius and an operating frequency of 100 Hertz. Each hinge mount may be formed from a material having a material loss factor greater than about 0.01 at 30 degrees Celsius and an operating frequency of 100 Hertz. Each hinge mount may be formed from a material having a material loss factor greater than about 0.02 at 30 degrees Celsius and an operating frequency of 100 Hertz. Each hinge mount may be formed from a material having a material loss factor greater than about 0.05 at 30 degrees Celsius and an operating frequency of 100 Hertz.

[0108] In some embodiments, each hinge mount may be supported by a material having a loss factor greater than 0.005 at 30 degrees Celsius and an operating frequency of 100 Hertz. Each hinge mount may be supported by a material having a loss factor greater than about 0.01 at 30 degrees Celsius and an operating frequency of 100 Hertz. Each hinge mount may be supported by a material having a loss factor greater than about 0.02 at 30 degrees Celsius and an operating frequency of 100 Hertz. Each hinge mount may be supported by a material having a loss factor greater than about 0.05 at 30 degrees Celsius and an operating frequency of 100 Hertz.

[0109] Preferably, the material is flexible and its deformation facilitates rotation of the diaphragm. Alternatively, the material rolls against another component to facilitate rotation of the diaphragm. In yet another alternative, the material is separate from the component primarily responsible for facilitating rotation of the diaphragm.

[0110] In some embodiments, this material accounts for a significant portion of the translational compliance experienced by the suspension system when the diaphragm translates in a direction perpendicular to the major surface at a frequency of 100 Hz.

[0111] In some embodiments, this material can contribute significantly to the mechanical damping of one or more resonant modes that involve large translational displacements of the suspension system in a direction perpendicular to the major plane of the diaphragm.

[0112] In some embodiments, each hinge mount can be damped for translational displacement along at least one axis, each hinge mount can be damped for translational displacement along at least two orthogonal axes, or each hinge mount can be damped for translational displacement along at least three orthogonal axes.

[0113] In some embodiments, each flexible hinge mount may be formed from an anisotropic material such that the anisotropy of each flexible hinge mount is more resistant to translational deformation in a direction substantially perpendicular to the coronal plane of the diaphragm than to rotational deformation of the mount.

[0114] In some embodiments, the Young's modulus of each flexible mount may be greater in a direction perpendicular to the coronal plane of the diaphragm.

[0115] In some embodiments, the flexible hinge mount may be formed from a foam material.

[0116] In some embodiments, each flexible hinge mount may have at least one substantially concave outer surface. Each flexible hinge mount may have at least one substantially concave outer surface extending along the longitudinal axis of the mount body. Each flexible hinge mount may have at least one substantially concave outer surface extending along the mount body in a direction parallel to the axis of rotation. Each flexible hinge mount may have at least one substantially concave cross-sectional profile of the at least one outer surface, the cross-sectional profile intersecting a transverse plane of the mount substantially perpendicular to the longitudinal axis or the axis of rotation of the mount. The one or more concave surfaces of each flexible hinge mount may face toward the diaphragm.

[0117] The concave surface or surfaces of each flexible hinge mount may face the transducer base structure.

[0118] In some embodiments, each flexible hinge mount may comprise a central region and at least one outer surface that is angled or curved inwardly toward the central region.

[0119] In some embodiments, each flexible hinge mount may comprise a central region and at least two outer surfaces angled or curved inward toward the central region, such that the central region is relatively thinner than the adjacent regions on either side.

[0120] In some embodiments, each flexible hinge mount may comprise a central axis and at least one outer surface that is angled or curved inwardly toward the central axis.

[0121] In some embodiments, each flexible hinge mount may be formed from a structure with varying density.

[0122] In some embodiments, each flexible hinge mount may include one or more cavities. Each cavity may be open. Each cavity may be filled with a fluid, such as a gas like air. Each cavity may be closed. Each cavity may be filled with a material that has a lower density than the rest of the mount body.

[0123] In some embodiments, each flexible hinge mount may comprise a plurality of substantially flexible elements. The elements may be in the form of spokes. The elements may be longitudinal. Each element may be substantially thin. Each element may be substantially short and thick. There may be a plurality of spokes extending between the diaphragm or diaphragm structure and the transducer base structure.

[0124] In some embodiments, each hinge mount may comprise a plurality of spaced-apart, radially-disposed longitudinal elements extending from a central base. The longitudinal axis of the central base may be substantially coaxial with the axis of rotation of the diaphragm or diaphragm structure. Each hinge element may be formed from one or more materials having a Young's modulus less than about 8 GPa such that the element flexes or deforms during operation. Each hinge element may be formed from one or more materials having a Young's modulus less than about 2 GPa. Each hinge element may be formed from one or more materials having a Young's modulus less than about 1 GPa. Each hinge element may be formed from one or more materials having a Young's modulus less than about 0.5 GPa.

[0125] In some embodiments, each hinge mount may include an air channel between elements. Each hinge mount may include a relatively low density material between elements.

[0126] In some embodiments, each flexible mount may comprise a cross-spring pivot hinge component coupled between the diaphragm and the transducer base structure, and each hinge component may be formed from a flexible and resilient material.

[0127] In some embodiments, each flexible mount may include two spaced-apart radially spaced spokes. In some embodiments, each flexible mount may include a plurality of spaced-apart radially spaced spokes. An inner end of each spoke may be coupled to a central body portion of the mount. An opposite outer end of each spoke may include a head. Each head or spoke may be configured to couple in situ to a corresponding formation in a wall of the transducer base structure. Each spoke may be held in situ under tension. Two or more spokes extend substantially radially from the primary hinge axis. A spoke may be oriented at an angle greater than 30 degrees relative to another spoke, more preferably greater than 45 degrees, and most preferably greater than 60 degrees.

[0128] In some embodiments, the diaphragm suspension may comprise one or more hinge joints each having a pair of cooperating contact surfaces configured to move relative to each other during operation to rotate the supported diaphragm or diaphragm structure, One of the contact surfaces may form part of the diaphragm or diaphragm structure, and the other contact surface may form part of the transducer base structure.

[0129] In some embodiments, each hinge mount may comprise a pair of hinge elements angled relative to one another, the pair of hinge elements may be substantially perpendicular to one another, or may be rotated about an axis, and the pair of hinge elements may comprise flexible elements.

[0130] In some embodiments, each flexible mount may comprise a cross-spring pivot hinge component.

[0131] In some embodiments, the diaphragm suspension may include at least one hinge joint, each having a pair of cooperating substantially rigid contact surfaces configured to move relative to each other during operation to rotate the supported diaphragm. The diaphragm suspension may include a biasing mechanism configured to compliantly bias the pair of cooperating contact surfaces toward each other during normal operation to maintain substantially consistent physical contact between the contact surfaces. One of the contact surfaces may form a portion of the diaphragm or diaphragm structure, and the other contact surface may form a portion of the transducer base structure.

[0132] In some embodiments, the diaphragm suspension may comprise one or more ball bearing hinges.

[0133] In some embodiments, the diaphragm suspension may include at least one hinge joint, each hinge joint including a ball bearing, the ball bearing including fewer than seven balls; each hinge joint including a ball bearing, the ball bearing including fewer than six balls; each hinge joint including a ball bearing, the ball bearing including fewer than five balls.

[0134] In some embodiments, the transduction mechanism may comprise a diaphragm-side transduction component configured to transfer forces to or from the diaphragm or diaphragm structure in use.

[0135] In some embodiments, the diaphragm-side transduction component may be directly coupled to the diaphragm or diaphragm structure.

[0136] In some embodiments, the diaphragm-side transduction component may be rigidly coupled to the diaphragm or diaphragm structure.

[0137] In some embodiments, the diaphragm-side transduction component may be rigidly connected to the diaphragm or diaphragm structure via one or more stiff intermediate components, which may have a Young's modulus of at least about 8 GPa, or at least about 20 GPa.

[0138] In some embodiments, the diaphragm-side transduction components may be integrated or integrally formed with the diaphragm or diaphragm structure.

[0139] In some embodiments, the diaphragm-side transduction component may extend along the side of the diaphragm or along the side of the diaphragm of the diaphragm structure.

[0140] In some embodiments, the diaphragm-side transduction component may extend along the edge of the diaphragm or along the edge of the diaphragm of the diaphragm structure.

[0141] In some embodiments, for a rotary motion transducer, the diaphragm-side transduction component may be coupled along an axis substantially parallel to the axis of rotation.

[0142] In some embodiments, the diaphragm-side transduction component may overlap the diaphragm or diaphragm structure. In the case of a rotary motion transducer, the diaphragm-side transduction component may overlap the diaphragm or diaphragm structure along the axis of rotation. The diaphragm-side transduction component may extend substantially parallel to the axis of rotation. Alternatively or additionally, the diaphragm-side transduction component may overlap the diaphragm or diaphragm structure along the center of mass of the diaphragm or diaphragm structure.

[0143] In some embodiments, in the case of a multi-diaphragm structure having multiple diaphragms extending from a common base of the diaphragm structure, the diaphragms may overlap the common base.

[0144] In some embodiments, in the case of a rotationally-moving transducer, the diaphragm-side transducer component may be disposed substantially only proximal to the axis of rotation. The diaphragm-side transducer component may be disposed within 75% of the length of the diaphragm, or the length of the diaphragm of the diaphragm structure, or the radius of the diaphragm structure from the axis of rotation. The diaphragm-side transducer component may be disposed within 50% of the length of the diaphragm, or the length of the diaphragm of the diaphragm structure, or the radius of the diaphragm structure from the axis of rotation. The diaphragm-side transducer component may be disposed within 40% of the length of the diaphragm, or the length of the diaphragm of the diaphragm structure, or the radius of the diaphragm structure from the axis of rotation. The diaphragm-side transducer component may be disposed within 30% of the length of the diaphragm, or the length of the diaphragm of the diaphragm structure, or the radius of the diaphragm structure from the axis of rotation.

[0145] In some embodiments, the diaphragm-side transduction component may be located within 20% of the maximum length dimension, such as the diagonal length dimension, of the diaphragm or the maximum length of the diaphragm of the diaphragm structure from the axis of rotation. The diaphragm-side transduction component may be located within 15% of the maximum length dimension from the axis of rotation. The diaphragm-side transduction component may be located within 10% of the maximum length dimension from the axis of rotation.

[0146] In some embodiments, for a rotary motion transducer, the diaphragm-side transduction component does not extend more than about 20%, or more than about 15%, or more than about 10% of the width dimension along the axis of rotation beyond the maximum width of the diaphragm, or the maximum width of the diaphragm structure, or the maximum width of the common base of the diaphragm structure. The maximum width dimension may be substantially parallel to the axis of rotation.

[0147] In some embodiments, the diaphragm-side transduction component may be substantially symmetric about at least one axis, or about at least two orthogonal axes, or about three orthogonal axes.

[0148] In some embodiments, the diaphragm-side transduction component may apply or transfer a substantially pure torque to or from the diaphragm or diaphragm structure, which may have a net translational force component of substantially zero.

[0149] In some embodiments, the diaphragm or diaphragm structure may be rigidly coupled to the transduction mechanism via one or more substantially planar parts or components.

[0150] In some embodiments, the diaphragm or diaphragm structure may be rigidly coupled to the transduction mechanism via one or more rigid components that are sufficiently straight and / or sufficiently supported and / or sufficiently thick that bending deformation of the rigid component(s) is substantially negligible during operation.

[0151] In some embodiments, the conversion mechanism may comprise an electromagnetic conversion mechanism comprising a magnet or magnetic structure operably coupled to a coil.

[0152] In some embodiments, the transduction mechanism may be substantially non-commutating. The magnet and coil may be separated by a fluid gap. The magnet may have a substantially curved surface adjacent the fluid gap. The fluid gap may be an air gap. The coil may have a substantially curved surface adjacent the fluid gap. The curved surfaces of the coil and magnet may be complementary. In the case of a rotary motion transducer, the surface of the magnet may be curved about the axis of rotation. In the case of a rotary motion transducer, the surface of the coil may be curved about the axis of rotation.

[0153] In some embodiments, the audio transducer may comprise a ferrofluid or material disposed between the coil and the magnet.

[0154] In some embodiments, the electromagnetic transduction mechanism may be substantially symmetrical about the sagittal plane of the audio transducer.

[0155] In some embodiments, the translation mechanism may include a magnet. The magnet may have a substantially non-alternating magnetic field. The magnet may be a permanent magnet. The magnet may be formed from a neodymium material. Alternatively, the magnet may be an electromagnet. The electromagnet may be a direct current electromagnet. Preferably, the magnet is not an armature.

[0156] In some embodiments, the magnet may be a diaphragm-side transduction component. The magnet may be configured to move with the diaphragm or diaphragm structure during operation. In the case of a rotary motion transducer, the magnet may be configured to rotate with the diaphragm or diaphragm structure about an axis of rotation during operation.

[0157] In some embodiments, the magnet may comprise one or more pole pieces rigidly coupled to the magnet. The pole pieces may collectively comprise a volume less than about 50% of the total volume of the magnet. The pole pieces may collectively comprise a volume less than about 30% of the total volume of the magnet. The pole pieces may collectively comprise a volume less than about 5% of the total volume of the magnet.

[0158] In some embodiments, the magnet has a convex outer surface on the side of the diaphragm. The magnet may have an opposing convex outer surface.

[0159] In some embodiments, the magnet may have an outer surface configured to couple to a corresponding surface of the diaphragm. The outer surface and the corresponding surface may be complementary. The outer surface may be substantially planar, and the corresponding surface of the diaphragm may be substantially planar.

[0160] In some embodiments, the magnet comprises one or more surfaces configured to couple to corresponding surfaces of the diaphragm. The one or more surfaces include a surface area sufficient to achieve a sufficiently rigid connection. The surfaces may be on sides of the magnet configured to extend adjacent to and / or in the same or similar plane as the major radially extending surfaces of the diaphragm. The surfaces may be directly coupled to normal stress stiffeners of the diaphragm.

[0161] The magnet may be directly coupled to the diaphragm at a region of the magnet most proximal to the diaphragm, which may be closer to the diaphragm than the adjacent coil and / or pole piece of the transducer mechanism.

[0162] The magnet may be directly coupled to a surface of the diaphragm body configured to exhibit a primary shear deformation force during operation.

[0163] The magnets may be bonded to the diaphragm using a high temperature adhesive, and the magnet bonding surfaces may be nickel plated and treated with an acid such as nitric acid.

[0164] The magnet and diaphragm may be coupled via one or more components configured to fit into corresponding openings or slots in one or both of the magnet and diaphragm.

[0165] In alternative embodiments, the magnet may be the base structure transduction component. The magnet may be relatively stationary during operation. The magnet may be rigidly coupled to the transducer base structure.

[0166] In some embodiments, the magnet may comprise a pair of opposing magnetic poles that extend substantially continuously along the length of the magnet. The magnet may consist of only a single pair of magnetic poles.

[0167] In some embodiments, the magnet may overlap the axis of rotation. The magnet may overlap the diaphragm along the axis of rotation. In a rotary motion transducer, magnetic poles may be positioned on either side of the axis of rotation. The axis of rotation may extend through the body of the magnet.

[0168] In some embodiments, the direction of the main internal magnetic field between the magnetic poles may be angled relative to the axis of rotation. The direction of the main magnetic field may be substantially perpendicular to the axis of rotation.

[0169] In some embodiments, the direction of the main internal magnetic field may be substantially angled relative to the coronal plane of the diaphragm or diaphragm of the diaphragm structure. The direction of the main magnetic field may be substantially orthogonal to the coronal plane of the diaphragm or diaphragm of the diaphragm structure.

[0170] In some embodiments, the direction of the main internal magnetic field may be substantially angled relative to the main radiation surface of the diaphragm or diaphragm of the diaphragm structure. The direction of the main magnetic field may be substantially perpendicular to the radiation surface of the diaphragm or diaphragm of the diaphragm structure.

[0171] In some embodiments, the magnetic poles may extend on either side of the coronal plane of the magnet.

[0172] In some embodiments, the primary internal magnetic field of the magnet between the poles may be substantially parallel to the coronal plane of the diaphragm. The primary internal magnetic field may be substantially angled, such as perpendicular, to the axis of rotation of the diaphragm.

[0173] In some embodiments, the magnet may be substantially curved about the axis of rotation. The outer surface of the diaphragm may be curved about the axis of rotation.

[0174] In some embodiments, the magnet may comprise a curved surface that is adjacent to a corresponding coil of the translation mechanism.

[0175] In some embodiments, the center of mass of the magnet or magnetic structure may be located at or proximate to the axis of rotation of the diaphragm or diaphragm structure.

[0176] In some embodiments, the magnets or magnetic structures may be positioned on either side of or proximate to the axis of rotation of the diaphragm, relative to the longitudinal axis of the diaphragm.

[0177] In some embodiments, the audio transducer may comprise one or more other strong ferromagnetic components rigidly connected to the magnet to carry strong magnetic flux from the magnet structure or assembly.

[0178] In some embodiments, the audio transducer may not include other components that include strong ferromagnetic materials other than the magnet structure or assembly.

[0179] A component with a strong ferromagnetic material is one that, in situ (with a stationary diaphragm), has a magnetic field of approximately 300 mμ r Greater than, or about 500 mμ r Greater than, or about 1000 mμ r It can refer to a component having a greater maximum relative permeability.

[0180] In some embodiments, the audio transducer may comprise one or more other strong ferromagnetic components other than the components of the magnetic structure or assembly, and the magnetic assembly is substantially distal from the other ferromagnetic components.

[0181] In some embodiments, the other ferromagnetic component may have one or more relatively large or major faces facing the magnet or magnetic structure or assembly. The relatively large or major faces of the other ferromagnetic component may be substantially distal from the nearest face or relatively large or major face of the magnet or magnetic structure or assembly to mitigate or significantly minimize the reaction of the other ferromagnetic component with the magnet or magnetic structure or assembly. The nearest face or relatively large or major face of the magnet or magnetic structure or assembly may be separated from the relatively large or major face of the other ferromagnetic component by a distance of at least about 0.4 times the maximum distance between the poles of the magnet or magnetic structure or assembly.

[0182] The nearest face, or relatively large face or major face, of the magnet or magnetic structure or assembly may be separated from the relatively large face or major face of the other ferromagnetic component by a distance of at least about 0.6 times the maximum distance between the poles of the magnet or magnetic structure or assembly. The nearest face, or relatively large face or major face, of the magnet or magnetic structure or assembly may be separated from the relatively large face or major face of the other ferromagnetic component by approximately the same distance as the distance between the poles of the magnet or magnetic structure or assembly.

[0183] The nearest face, or relatively large face or major face, of the magnet or magnetic structure or assembly may be separated from the relatively large face or major face of the other ferromagnetic component along an axis substantially perpendicular to the axis of rotation by a distance of at least about 0.4 times the maximum distance between the poles of the magnet or magnetic structure or assembly. The nearest face, or relatively large face or major face, of the magnet or magnetic structure or assembly may be separated from the relatively large face or major face of the other ferromagnetic component along an axis substantially perpendicular to the axis of rotation by a distance of at least about 0.6 times the maximum distance between the poles of the magnet or magnetic structure or assembly.

[0184] The nearest face, or larger or major face, of the magnet or magnetic structure or assembly may be separated from the larger or major face of the other ferromagnetic component by approximately the same distance along an axis substantially perpendicular to the axis of rotation as the distance between the poles of the magnet or magnetic structure or assembly.

[0185] The nearest face, or larger or major face, of the magnet or magnetic structure or assembly may be separated from the larger or major face of the other ferromagnetic component by a distance along an axis substantially perpendicular to the axis of rotation that is at least about 0.4 times the largest dimension of the magnet.

[0186] The nearest face, or larger or major face, of the magnet or magnetic structure or assembly may be separated from the larger or major face of the other ferromagnetic component by a distance along an axis substantially perpendicular to the axis of rotation that is at least about 0.6 times the largest dimension of the magnet.

[0187] The nearest face, or larger or major face, of the magnet or magnetic structure or assembly may be separated from the larger or major face of the other ferromagnetic component by a distance along an axis substantially perpendicular to the axis of rotation approximately equal to the largest dimension of the magnet.

[0188] The nearest face, or relatively large face or major face, of a magnet or magnetic structure or assembly may be separated from the relatively large face or major face of the other ferromagnetic component by a distance of at least about 0.4 times the maximum length of the magnet. The nearest face, or relatively large face or major face, of a magnet or magnetic structure or assembly may be separated from the relatively large face or major face of the other ferromagnetic component by a distance of at least about 0.6 times the maximum length of the magnet. The nearest face, or relatively large face or major face, of a magnet or magnetic structure or assembly may be separated from the relatively large face or major face of the other ferromagnetic component by a distance approximately equal to the maximum length of the magnet.

[0189] The nearest face, or relatively large face or major face, of a magnet or magnetic structure or assembly may be separated from the relatively large face or major face of the other ferromagnetic component by a distance of at least about 0.4 times the maximum length of the magnet. The nearest face, or relatively large face or major face, of a magnet or magnetic structure or assembly may be separated from the relatively large face or major face of the other ferromagnetic component by a distance of at least about 0.6 times the maximum length of the magnet. The nearest face, or relatively large face or major face, of a magnet or magnetic structure or assembly may be separated from the relatively large face or major face of the other ferromagnetic component by a distance approximately equal to the maximum length of the magnet.

[0190] The nearest or larger face of the magnet assembly is separated from the larger face of the other ferromagnetic component in a direction perpendicular to the axis by at least about 0.4 times the largest dimension of the magnet in the area of ​​said face in a direction parallel to said face. The nearest or larger face of the magnet assembly is separated from the larger face of the other ferromagnetic component in a direction perpendicular to the axis by about 0.6 times the largest dimension of the magnet in the area of ​​said face in a direction parallel to said face. The nearest or larger face of the magnet assembly is separated from the larger face of the other ferromagnetic component in a direction perpendicular to the axis by a distance substantially similar to the largest dimension of the magnet in the area of ​​said face in a direction parallel to said face.

[0191] In some embodiments, the transducer does not include a magnet or other ferromagnetic component that exerts a force on the magnetic structure or assembly that is greater than 70 times, more preferably greater than 50 times, and most preferably greater than 40 times the force due to gravity acting on the magnet assembly.

[0192] In some embodiments, the transducer comprises other ferromagnetic components facing the magnet or magnetic structure or assembly that pull the magnet or magnetic structure or assembly in an opposite direction, hi some embodiments, the net force on the magnet or magnetic structure or assembly due to the other ferromagnetic components is negligible or near zero.

[0193] In some embodiments, the net force exerted on the diaphragm by the other ferromagnetic components is no more than 20 times greater than the force on the diaphragm due to the effect of gravity, preferably no more than 10 times greater, and most preferably no more than 5 times greater.

[0194] In some embodiments, the net force exerted on the diaphragm by the other ferromagnetic components can approximately cancel the force on the diaphragm due to the effect of gravity in situ.

[0195] In some embodiments, the magnet may be encased in a metal part with a density of less than about 2.2 grams per cubic centimeter. In some embodiments, the metal part near the magnet may have a solid volume less than the solid volume of the magnet or less than about 0.8 times the solid volume of the magnet. The metal part may be positioned at an average radius less than the average radius of the magnet.

[0196] In some embodiments, the transduction mechanism may include a coil. The coil may comprise one or more coil windings. The coil may be a diaphragm-side transduction component and may be configured to move with the diaphragm or diaphragm structure during operation.

[0197] In some embodiments, the coil is the base structure side transduction component. The coil may comprise a single coil winding that extends around a corresponding magnet of the transduction mechanism.

[0198] In some embodiments, the coil cannot be intimately attached to the ferromagnetic core.

[0199] In some embodiments, the audio transducer may further include a shield formed from a ferromagnetic material configured to substantially reduce magnetic attraction or repulsion of nearby, unrelated ferromagnetic material toward or away from the transducer mechanism. The shield can reduce movement, such as twisting, of the transducer mechanism toward or away from the unrelated ferromagnetic material. The shield may extend around the transducer mechanism. The shield should not be in close contact with any of the coils. The shield may be substantially distal to each coil to provide a gap therebetween. The gap may be at least 1 mm, for example. The shield can substantially reduce the net force acting on the diaphragm or diaphragm structure to zero.

[0200] In some embodiments, the ferromagnetic shield may have holes or other gaps to facilitate the passage of sound waves.

[0201] In some embodiments, the ferromagnetic shield may double as a grill.

[0202] In some embodiments, the face or side of the coil distal from the magnet of the electromagnetic mechanism cannot have any strongly ferromagnetic material tightly attached to it. In some embodiments, the face or side of the coil distal from the magnet of the electromagnetic mechanism cannot have any strongly ferromagnetic material rigidly connected to it.

[0203] In some embodiments, the face or side of the coil distal from the magnet of the electromagnetic mechanism may have a clearance of at least 1 mm, more preferably at least 2 mm, and most preferably at least 4 mm to any strong ferromagnetic material.

[0204] In some embodiments, the audio transducer may not include any pole pieces around the coil. In alternative embodiments, the audio transducer may include pole pieces around the coil.

[0205] In some embodiments, the coil may be coupled around a pin on a hinge mount of the diaphragm suspension.

[0206] In some embodiments, the coil may be routed around the pivot pin of the hinge connecting the diaphragm suspension.

[0207] In some embodiments, the coil may be positioned adjacent to and wound around the magnet of the translation mechanism.

[0208] In some embodiments, the coil may be positioned adjacent to the magnet of the translation mechanism and wrapped around a region adjacent to a pole of the magnet, which may be immediately adjacent to the pole.

[0209] In some embodiments, the shortest distance between the magnet or magnetic structure and the coil is less than about 1.5 mm, more preferably less than about 1 mm, and most preferably less than about 0.5 mm.

[0210] In some embodiments, the coils may be symmetrical on either side of the magnet or magnetic structure.

[0211] In some embodiments, the coil extends in a plane substantially transverse to the longitudinal axis of the diaphragm.

[0212] In some embodiments, the coils extend substantially parallel to and along either side of the axis of rotation.

[0213] In some embodiments, multiple coils may be positioned adjacent to the magnet of the translation mechanism, each wound around a region adjacent to one of the poles of the magnet. This region may be immediately adjacent to the pole. The multiple coils may not be electrically and magnetically connected (e.g., by a ferromagnetic core). The coils may be connected. The coils may be connected in series or in parallel. A first coil may be positioned adjacent to the magnet of the translation mechanism and wound around a region adjacent to the first pole of the magnet, and a second coil may be positioned adjacent to the magnet and wound around a region adjacent to the second pole of the magnet.

[0214] In some embodiments, the longitudinal axis of the coil may be substantially perpendicular to the main magnetic field of the corresponding magnet of the transducer mechanism. The coil axis may intersect a central region of the magnet. The coil axis may intersect a central region of the longitudinal axis of the magnet.

[0215] In some embodiments, the coil may have a resistance of less than about 2.5 ohms. The coil may have a resistance of less than about 2 ohms. The coil may have a resistance of less than about 1 ohm.

[0216] In some embodiments, the transduction mechanism may comprise a piezoelectric mechanism, and the diaphragm-side transduction component may be a component or part of the piezoelectric mechanism.

[0217] In some embodiments, the transducer base structure may include a plurality of cooling fins.

[0218] In some embodiments, the transducer base structure may be formed from alumina.

[0219] In some embodiments, the audio transducer may further comprise a decoupling mounting system that flexibly mounts the transducer base structure to an adjacent component of the audio transducer other than the diaphragm or diaphragm structure.

[0220] In some embodiments, the audio transducer may further comprise a housing or baffle configured to surround the audio transducer, and the decoupling mounting flexibly mounts the transducer base structure to the housing or baffle.

[0221] In some embodiments, the decoupling mounting system may include at least one transducer nodal axis mount configured to be located at or proximate to a predetermined transducer nodal axis of the audio transducer. The predetermined transducer nodal axis may be determined by identifying the axis of rotation of the transducer base structure when the audio transducer is in a substantially unsupported actuated state (where the audio transducer is substantially decoupled from the housing and the transducer base structure exhibits a reaction force for the movement during diaphragm rotation). In some embodiments, the predetermined transducer nodal axis may be determined using a computer simulation of a model of the audio transducer in a substantially unsupported actuated state.

[0222] In some embodiments, the decoupling system may include at least one distal mount configured to be located distally from a given transducer node axis.

[0223] In some embodiments, the at least one transducer node axial mount may be relatively less compliant and / or relatively less flexible than the at least one distal mount.

[0224] In some embodiments, the decoupling system may include a pair of transducer node axis mounts disposed on opposite sides of the transducer base structure. Each transducer node axis mount preferably includes a pin rigidly coupled to the transducer base structure and extending laterally from one side of the transducer base structure along an axis substantially aligned with the transducer node axis. Each transducer node axis mount preferably further includes a bushing rigidly coupled around the pin and configured to be disposed within a corresponding recess in the housing. The corresponding recess in the housing preferably includes a slug for rigidly receiving and retaining the bushing within the recess.

[0225] In some embodiments, each distal mount may comprise a substantially flexible mounting pad. The decoupling system preferably comprises a pair of mounting pads connected between an outer surface of the transducer base structure and an inner surface of the housing. The mounting pads are preferably joined on opposite sides of the transducer base structure. Each mounting pad preferably has a substantially tapered width along its depth, with a top end and a base end. The base end is preferably rigidly connected to one of the transducer base structure or the housing, and the top end is preferably connected to the other of the transducer base structure or the housing.

[0226] In some embodiments, the audio transducer may be an electroacoustic transducer / speaker configured to generate sound pressure from an input audio signal.

[0227] In some embodiments, the audio transducer may be an acoustoelectric transducer / microphone configured to generate an audio signal from an input sound pressure.

[0228] In some embodiments, the audio transducer may include a housing for enclosing the diaphragm or diaphragm structure, the transducer base structure, and the transduction mechanism. The housing may be made from a plastic material.

[0229] In some embodiments, the audio transducer may be a mid-range and high-range transducer configured to transduce sounds in the frequency range 200 Hz to 20 kHz.

[0230] In some embodiments, the audio transducer may be a low frequency transducer configured to transduce sounds in the frequency range from about 20 Hz to about 200 Hz.

[0231] In some embodiments, the audio transducer may be a personal audio transducer configured to transduce sounds in the frequency range of about 20 Hz to about 20 kHz.

[0232] In some embodiments, the audio transducer may have a fundamental resonant frequency below 100 Hz, or below about 70 Hz, or most preferably below 50 Hz.

[0233] In some embodiments, each hinge mount of the diaphragm suspension has a Young's modulus that is sufficiently low so that the fundamental diaphragm resonant frequency occurs at a frequency below about 100 Hz. In some embodiments, each hinge mount of the diaphragm suspension has a Young's modulus that is sufficiently low so that the fundamental diaphragm resonant frequency occurs at a frequency below about 70 Hz. In some embodiments, each hinge mount of the diaphragm suspension has a Young's modulus that is sufficiently low so that the fundamental diaphragm resonant frequency occurs at a frequency below about 50 Hz.

[0234] In some embodiments, the audio transducer may have a translational resonant frequency greater than about 200 Hz, or greater than about 300 Hz, or greater than about 400 Hz.

[0235] In some embodiments, the one or more diaphragm suspension components are sufficiently stiff so that the diaphragm resonant frequency associated with translational compliance occurs at a frequency greater than about 200 Hz, more preferably greater than about 300 Hz, and most preferably greater than about 400 Hz. The diaphragm assembly resonant frequency associated with translational compliance can be associated with large displacements of the diaphragm in a direction perpendicular to the coronal plane.

[0236] In some embodiments, each hinge mount of the diaphragm suspension is sufficiently stiff so that the diaphragm resonant frequency associated with translational compliance occurs at a frequency greater than about 200 Hz, more preferably greater than about 300 Hz, and most preferably greater than about 400 Hz. The diaphragm assembly resonant frequency associated with translational compliance can be associated with large displacements of the diaphragm in a direction perpendicular to the coronal plane.

[0237] In some aspects, the present invention may generally consist of an audio device configured for use within about 10 cm of a user's ear, the audio device comprising a housing and an audio transducer according to any one of the aforementioned aspects disposed within the housing.

[0238] In some embodiments, the audio device may comprise at least one interface device sized and configured to be placed against a user's ear in use, the interface device comprising a housing and an audio transducer.

[0239] Each interface device may be configured to straddle the user's head at or adjacent the user's ear in use.

[0240] Each audio device may comprise a pair of interface devices for the user's ears, the pair of interface devices being configured to reproduce at least two independent audio signals via associated audio transducers.

[0241] In some embodiments, each interface device is a headphone cup configured to be worn on or around a user's ear during use.

[0242] In some embodiments, each interface device is an interface plug configured to reside in, adjacent to, or within a user's ear canal during use. Each earbud interface may not seal around the associated ear canal during wear. Each interface device may include an air channel extending from the ear canal opening to an air vent on the device.

[0243] In some embodiments, the interface device is a mobile phone sound interface.

[0244] In some embodiments, the device is a hearing aid interface.

[0245] In some aspects, the present invention may generally consist of a mobile phone device including a housing and an audio transducer according to any one of the preceding aspects disposed within the housing.

[0246] In some aspects, the present invention may generally consist of a hearing aid comprising a housing and an audio transducer according to any one of the above aspects disposed within the housing.

[0247] In some aspects, the present invention generally comprises: a housing having a cavity for an audio transducer, the cavity having a substantially short depth dimension; an audio transducer according to any one of the preceding aspects; Equipped with The audio transducer may be said to comprise an electronic device having an audio transducer disposed within the cavity, the diaphragm configured to rotatably vibrate between first and second extreme positions about a primary axis of rotation during operation, the audio transducer oriented within the cavity such that the primary axis of rotation is substantially parallel to a depth dimension of the cavity, and the total linear displacement of the end of the diaphragm most distal from the primary axis of rotation along a plane substantially perpendicular to the depth dimension is substantially the same as or longer than the depth dimension of the cavity.

[0248] In some aspects, the present invention generally comprises: a housing having a cavity for an electroacoustic transducer, the depth dimension of the cavity being less than a substantially perpendicular length dimension of the cavity and / or less than a substantially perpendicular width dimension of the cavity; an audio transducer according to any one of the preceding aspects, having a diaphragm disposed within the cavity and configured to rotate about an axis of rotation during operation, wherein the electroacoustic transducer is oriented within the cavity such that the axis of rotation of the diaphragm is substantially parallel to a depth dimension of the cavity; Equipped with It can be said to comprise an electronic device in which the depth dimension of the housing is substantially less than the width and length dimensions of the housing.

[0249] In some embodiments, the depth dimension of the housing may be significantly less than the width and length dimensions of the housing, for example, the depth dimension of the housing may be less than about 0.2 times the width and / or length dimension of the housing, less than about 0.15 times the width and / or length dimension of the housing, or less than about 0.1 times the width and / or length dimension of the housing.

[0250] In another aspect, the invention generally comprises: A housing, a pair of opposing major surfaces connected by one or more side surfaces, each major surface having a relatively larger surface area than each of the side surfaces; a cavity for an electroacoustic transducer, the cavity having a short depth dimension substantially perpendicular to a major surface; a housing having an electroacoustic transducer according to any one of the preceding aspects, having a diaphragm disposed within the cavity and configured to rotatably vibrate, during operation, about an axis of rotation between first and second extreme positions, the electroacoustic transducer being oriented within the cavity such that the axis of rotation of the diaphragm is substantially parallel to a depth dimension of the cavity; It can be said that the electronic device is composed of:

[0251] In some aspects, the present invention generally comprises: a housing having a cavity for an electroacoustic transducer, the depth dimension of the cavity being less than a substantially perpendicular length dimension of the cavity and / or less than a substantially perpendicular width dimension of the cavity; an audio transducer having a diaphragm disposed within a cavity and configured to rotate about an axis of rotation during operation, the electroacoustic transducer being oriented within the cavity such that the axis of rotation of the diaphragm is substantially parallel to a depth dimension of the cavity; Equipped with The electronic device comprises a housing having a depth dimension that is substantially less than the width and length dimensions of the housing.

[0252] In some aspects, the present invention generally comprises: A housing, a pair of opposing major surfaces connected by one or more side surfaces, each major surface having a relatively larger surface area than each of the side surfaces; a cavity for an electroacoustic transducer, the cavity having a short depth dimension substantially perpendicular to a major surface; a housing having an audio transducer according to any one of the preceding aspects, having a diaphragm disposed within the cavity and configured to rotatably vibrate, in operation, about an axis of rotation between first and second extreme positions, wherein the electroacoustic transducer is oriented within the cavity such that the axis of rotation of the diaphragm is substantially parallel to a depth dimension of the cavity; It can be said that the electronic device is composed of:

[0253] In some aspects, the present invention generally comprises: a housing having a cavity for an audio transducer, the depth dimension of the cavity being shorter than a substantially orthogonal length dimension of the cavity and a substantially orthogonal width dimension of the cavity; an audio transducer according to any one of the preceding aspects, having a diaphragm disposed within the cavity and configured to rotate about an axis of rotation during operation, the audio transducer being oriented within the cavity such that the axis of rotation of the diaphragm is substantially parallel to a depth dimension of the cavity; It can be said that the electronic device is composed of:

[0254] In some aspects, the present invention generally comprises: a housing having a cavity for an electroacoustic transducer, the cavity having a substantially short depth dimension; an audio transducer according to any one of the preceding aspects, having a diaphragm disposed within the cavity and configured to rotatably vibrate, during operation, about an axis of rotation between first and second extreme positions, wherein the electroacoustic transducer is oriented within the cavity such that the axis of rotation of the diaphragm is substantially parallel to a depth dimension of the cavity, at least a component of total linear displacement of a distal end of the diaphragm along a plane substantially perpendicular to the depth dimension is substantially the same as or longer than the depth dimension of the cavity, the component of total linear displacement being substantially perpendicular to the depth dimension, and the distal end of the diaphragm is at an end of the diaphragm most distal from the axis of rotation; It can be said that the electronic device is composed of:

[0255] In some aspects, the present invention generally comprises: a housing having a cavity for an electroacoustic transducer, the cavity having a substantially short depth dimension; an audio transducer according to any one of the preceding aspects, having a diaphragm disposed within the cavity and configured to rotatably vibrate, during operation, about an axis of rotation between first and second extreme positions, wherein the electroacoustic transducer is oriented within the cavity such that the axis of rotation of the diaphragm is substantially parallel to a depth dimension of the cavity, at least a component of total linear displacement of a distal end of the diaphragm along a plane substantially perpendicular to the depth dimension is substantially the same as or greater than the depth dimension of the cavity, the component of total linear displacement being substantially perpendicular to the depth dimension, and the distal end of the diaphragm is at an end of the diaphragm most distal from the axis of rotation; It can be said that the electronic device is composed of:

[0256] In some aspects, the present invention generally comprises: an audio device having an audio transducer according to any one of the preceding aspects; an audio conditioning system operatively coupled to the audio device for optimizing the audio signal at the input of the transducer; It can be said that the audio system is composed of the above.

[0257] The audio conditioning system may be implemented in the audio devices of the audio system or in an external or remote device.

[0258] In another aspect, the invention generally comprises: an audio transducer according to any one of the preceding aspects; an audio tuning system operatively coupled to the audio transducer for optimizing an input audio signal to the transducer; It can be said that the audio device is composed of an audio device having the above.

[0259] The audio conditioning system may be implemented with analog and / or digital circuits.

[0260] In some embodiments, the audio tuning system of the present invention includes an equalizer configured to correct the received audio signal for each output channel of an associated audio device. The equalizer is configured to compensate for the characteristics of the associated audio transducer. Such characteristics may include any combination of one or more of the frequency response of the audio transducer, the phase response of the audio transducer, the impulse response of the audio transducer, and / or a lumped mass-spring-damper characteristic (where the fundamental mode is modeled, and optionally one or more translational modes are also modeled).

[0261] In some embodiments, the equalizer may be configured to remove steps in the frequency response of the audio signal and deliver a corrected audio signal to the transduction mechanism of the audio transducer.

[0262] In some embodiments, the equalizer may be configured to remove spikes or blips in the frequency response of the audio signal and deliver a corrected audio signal to the transduction mechanism of the associated audio transducer. A spike or blip may, for example, cause a spike of at least 1 dB in the frequency response.

[0263] The equalizer may be configured to remove phase spikes or blips or steps in the phase response of the audio signal.

[0264] In some embodiments, the audio tuning system may be configured to correct the frequency response and / or phase response and / or transient response of an input signal to the transducer mechanism based on the diaphragm fundamental resonant frequency.

[0265] In some embodiments, the audio tuning system may be configured to correct the frequency and / or phase and / or transient response of an input signal to the transducer mechanism to compensate for amplitude and / or phase and / or transient characteristics associated with lumped parameter characteristics of the diaphragm, such as a mass-spring-damper, which may include both the fundamental diaphragm resonance mode and one or more resonance modes that include a significant translational component of the diaphragm assembly associated with compliance of the hinge in the translational direction.

[0266] In some embodiments, the audio tuning system may be configured to increase the frequency response of the audio signal with increasing frequency at the input of the transducer to compensate for high frequency roll-off, which may be related to coil inductance.

[0267] In some embodiments, the audio tuning system may be configured to incorporate a frequency response curve that includes a step change in sound pressure occurring at or near a frequency corresponding to compensation for the effect of a resonant mode having a motion that includes translational motion of the diaphragm structure due to the translational compliance of the diaphragm suspension. The incorporated frequency response curve may also include correction for response peaks and / or response valleys associated with a resonant mode having a motion that includes translational motion of the diaphragm structure due to the translational compliance of the diaphragm suspension.

[0268] In some embodiments, the audio tuning system may include a high-pass filter having an input configured to operably couple to the audio source and an output configured to operably couple to the transducer mechanism to attenuate audio signals from the audio source at frequencies below one or more predetermined cutoff frequencies. In embodiments where the diaphragm suspension system is also sufficiently flexible, resonant frequencies associated with resonant modes associated with the compliance of the diaphragm suspension system may be lower than one or more of the predetermined cutoff frequencies.

[0269] In some embodiments, the audio conditioning system comprises a high-pass filter for filtering relatively low frequency components of the input audio signal, the filter also being configured, in operation, to apply the filtered audio signal to the transduction mechanism of an associated transducer.

[0270] The filter may be configured to filter frequency components of the associated audio transducer based on a lower roll-off frequency of the transducer's frequency response.

[0271] In some embodiments, the diaphragm suspension of an audio transducer may be sufficiently compliant so that the resonant frequency of the diaphragm associated with the translational compliance is below the cutoff frequency of the filter. The cutoff frequency may be, for example, the -3 dB frequency of the filter. The resonant mode is preferably not the principal resonant mode of the diaphragm. At the resonant mode frequency, the diaphragm preferably remains substantially rigid. The resonant mode preferably includes translational compliance / movement of the diaphragm in the region of the major axis. The resonant mode preferably includes compliance / movement of the suspension system that favors rotation of the diaphragm about an axis other than the major axis. This axis is preferably aligned parallel to the major axis. The translational motion preferably has a significant component perpendicular to the major surface of the diaphragm. The resonant mode is preferably a mode that results in a resonant peak of greater than 1 dB in a frequency response measurement, more preferably greater than 2 dB, and most preferably greater than 3 dB. The resonant mode is preferably a mode associated with a level step of greater than 0.5 dB, more preferably greater than 1 dB, and most preferably greater than 1.5 dB in a frequency response plot.

[0272] The diaphragm resonant frequencies associated with translational hinge compliance may involve large displacements of the diaphragm perpendicular to the coronal plane. When measured on-axis at 1 m, the diaphragm resonant frequencies associated with translational hinge compliance may result in a shift in the associated frequency response of 1 dB or more. When measured on-axis at 1 m, the diaphragm assembly resonant frequencies associated with translational hinge compliance may result in a step in the associated frequency response of 0.5 dB or more.

[0273] In some embodiments, the audio device may further comprise an amplifier for amplifying an input audio signal and outputting the amplified signal to the conversion mechanism during operation. The amplifier may be configured to receive the output current as feedback at the input of the amplifier. The amplifier may be digital and / or analog.

[0274] In some aspects, the present invention can be generally described as comprising a method of manufacturing an audio transducer having a diaphragm, a transducer base structure, and a transduction mechanism, the method comprising: a) determining the nodal axis of the diaphragm; b) coupling a transduction mechanism to the diaphragm and transducer base structure; c) rotatably mounting the diaphragm to the transducer base structure via a diaphragm suspension system such that the axis of rotation of the diaphragm relative to the transducer base structure is disposed in a plane that is substantially perpendicular to the coronal plane of the diaphragm and that contains the nodal axis of the diaphragm; Includes:

[0275] In some embodiments, the order of steps a) to c) may be changed, provided that step c) is performed after step a).

[0276] In some embodiments, the rotation axis may be substantially coaxial with the nodal axis.

[0277] In some embodiments, determining the nodal axes of the diaphragm may include operating the diaphragm in an essentially unsupported state and observing an axis of rotation indicative of the nodal axes.

[0278] In some embodiments, the step of determining the nodal axis of the diaphragm comprises: generating a computer model of an audio transducer; simulating an operating condition in which the model translation mechanism rotates the model diaphragm in a substantially unsupported state relative to the model transducer base structure; determining a rotation axis of the diaphragm of the model from the simulation; determining the nodal axis of the audio transducer from the axis of rotation of the diaphragm of the model; may include:

[0279] In some embodiments, this operating state has a negligible effect on the nodal axis position of the diaphragm suspension. The time duration of this operating state may be short enough, and / or the operating frequency of this state may be high enough, that the effect of the diaphragm suspension on the nodal axis position is negligible. In this operating state, bending of the diaphragm (relative to bending of the diaphragm suspension / diaphragm displacement) has a negligible effect on the nodal axis position. This operating state may be long enough, and / or the operating frequency of this state may be low enough, that the diaphragm remains substantially rigid, or at least that any deformation of the diaphragm has a negligible effect on the determined nodal axis position.

[0280] In some embodiments, equivalent computer modeling techniques can be used to design the mass distribution of the diaphragm and / or the mass distribution of the transducer and / or the excitation position and direction of the diaphragm so that the nodal axis occurs at the target location.

[0281] In some embodiments, determining the nodal axes of the diaphragm comprises using the laws of kinematics and / or applying Newton's second law.

[0282] In some embodiments, the diaphragm can be assumed to be substantially rigid. The transducer base structure can be assumed to be substantially rigid. The diaphragm suspension can be assumed to have substantially negligible influence on the motion. A calculation can be made of the position of the axis of rotation of the diaphragm. As an initial condition, the relative motion between the diaphragm and the transducer base structure can be zero. The force can be applied in the same direction and position as it would be applied in a real driver. The force can be applied for a short enough time so that the resulting displacement is small or negligible. A position of the diaphragm with substantially no translational motion after the force is applied can be determined.

[0283] In some embodiments, equivalent techniques based on the laws of kinematics can be used to design the mass distribution of the diaphragm and / or the mass distribution of the transducer and / or the excitation position and direction of the diaphragm so that the nodal axis occurs at some target position.

[0284] In some embodiments, the step of determining the nodal axis of the diaphragm comprises: generating a physical model of an audio transducer; operating a translation mechanism of the model to rotate the diaphragm of the model substantially unsupported relative to a transducer base structure of the model; determining an axis of rotation of the model diaphragm relative to the transducer base structure; determining the nodal axis of the audio transducer from the axis of rotation of the diaphragm of the model; may include:

[0285] In some embodiments, this operating state has a negligible effect on the nodal axis position of the diaphragm suspension. The time duration of this operating state may be short enough, and / or the operating frequency of this state may be high enough, that the effect of the diaphragm suspension on the nodal axis position is negligible. In this operating state, bending of the diaphragm (relative to bending of the diaphragm suspension / diaphragm displacement) has a negligible effect on the nodal axis position. This operating state may be long enough, and / or the operating frequency of this state may be low enough, that the diaphragm remains substantially rigid, or at least that any deformation of the diaphragm has a negligible effect on the determined nodal axis position.

[0286] In some embodiments, determining the axis of rotation of the model may include measuring the axis using one or more sensors or measurement devices, such as an accelerometer, a Laser Doppler Vibrometer (LDV), or a proximity sensor.

[0287] In some aspects, the invention can be generally said to comprise a method of manufacturing an audio transducer having a diaphragm, a transducer base structure, and a transduction mechanism, the method comprising: a) i. coupling a transduction mechanism to a diaphragm and a transducer base structure; ii. rotatably mounting the diaphragm to a transducer base structure via a diaphragm suspension system; Assembling an audio transducer by b) operating a translation mechanism to rotate a diaphragm of the partially assembled audio transducer; c) analyzing one or more operational characteristics of the partially assembled audio transducer; d) adjusting one or more physical characteristics of the partially assembled audio transducer to optimize one or more operating characteristics; e) repeating steps b) through d) if necessary until one or more desired criteria of one or more operating characteristics are achieved; Includes:

[0288] In some embodiments, the desired criteria may be predetermined.

[0289] In some embodiments, b) may additionally or alternatively include operating the driver in a manner that has a non-negligible effect on the nodal position of the diaphragm suspension.

[0290] In some embodiments, the one or more operating characteristics may include any one or more of the frequency response of the transducer at least within the intended operating frequency range.

[0291] In some embodiments, step c) may include analyzing the frequency response of the transducer to determine whether a value of a parameter indicative of one or more step changes in the frequency response is greater than a predetermined threshold.

[0292] In some embodiments, step c) may include analyzing the frequency response of the transducer to determine whether a peak value of the frequency response is greater than a predetermined threshold.

[0293] In some embodiments, the one or more physical properties may include any combination of one or more of: a position of the diaphragm suspension system relative to the diaphragm; a position of the axis of rotation of the diaphragm relative to the transducer base structure; a mass profile of the transducer base structure; a mass profile of the diaphragm; one or more dimensions of the diaphragm; a shape profile of the diaphragm; a shape profile of the diaphragm suspension system; a stiffness profile of the diaphragm suspension system; and a force generation profile of the transduction mechanism.

[0294] In some aspects, the invention can be generally said to comprise a method of manufacturing an audio transducer having a diaphragm, a transducer base structure, and a transduction mechanism, the method comprising: a) determining the center of mass axis of the diaphragm; b) coupling a transduction mechanism to the diaphragm and transducer base structure; c) rotatably mounting the diaphragm to the transducer base structure via a diaphragm suspension system such that the axis of rotation of the diaphragm relative to the transducer base structure is disposed in a plane that is substantially perpendicular to the coronal plane of the diaphragm and that contains the center of mass axis of the diaphragm; Includes:

[0295] In some embodiments, the axis of rotation may be substantially coaxial with the center of mass axis.

[0296] In some aspects, the present invention generally comprises: A diaphragm and a transducer base structure; a diaphragm suspension system configured to flexibly and rotatably mount the diaphragm relative to the transducer base structure such that, during operation, the diaphragm can rotatably vibrate about an axis of rotation relative to the transducer base structure, the diaphragm suspension system comprising at least one flexible mount coupled between an outer side of the diaphragm and an adjacent side of the transducer base structure; an electromagnetic conversion mechanism operatively coupled to the diaphragm for converting between audio signals and sound pressure, the electromagnetic conversion mechanism comprising a magnet or magnetic structure and an associated conductive coil disposed in situ within the magnetic field of the magnet or magnetic structure; It can be said that the audio transducer is composed of an audio transducer having:

[0297] In some aspects, the present invention generally comprises: A diaphragm and a transducer base structure; a diaphragm suspension system configured to flexibly and rotatably mount the diaphragm relative to the transducer base structure such that, during operation, the diaphragm can rotatably vibrate about an axis of rotation relative to the transducer base structure; an electromagnetic conversion mechanism operatively coupled to the diaphragm for converting between audio signals and sound pressure, the electromagnetic conversion mechanism comprising a magnetic structure and an associated conductive coil disposed in situ within the magnetic field of the magnetic structure, the electromagnetic conversion mechanism positioned at or proximal to the axis of rotation, thereby exerting a torque on the diaphragm with substantially no net translational force component during operation; It can be said that the audio transducer is composed of an audio transducer having:

[0298] In some aspects, the present invention generally comprises: A diaphragm and a transducer base structure; a diaphragm suspension system configured to rotatably mount the diaphragm relative to the transducer base structure such that, in operation, the diaphragm can rotatably vibrate about an axis of rotation relative to the transducer base structure, the axis of rotation of the diaphragm being arranged substantially coaxial with a predetermined nodal axis of the diaphragm; an electromagnetic conversion mechanism operatively coupled to the diaphragm for converting between audio signals and sound pressure, the electromagnetic conversion mechanism comprising a magnetic structure and an associated conductive coil structure disposed in situ within the magnetic field of the magnetic structure, the magnetic structure configured to move during operation; It can be said that the audio transducer is composed of an audio transducer having:

[0299] In some aspects, the present invention generally comprises: A diaphragm and a transducer base structure; a diaphragm suspension system configured to rotatably mount the diaphragm relative to the transducer base structure such that, in operation, the diaphragm can rotatably vibrate about an axis of rotation relative to the transducer base structure, the axis of rotation of the diaphragm being arranged substantially coaxial with a center of mass axis of the diaphragm; an electromagnetic conversion mechanism operatively coupled to the diaphragm for converting between audio signals and sound pressure, the electromagnetic conversion mechanism comprising a magnetic structure and an associated conductive coil structure disposed in situ within the magnetic field of the magnetic structure, the magnetic structure configured to move during operation; It can be said that the audio transducer is composed of an audio transducer having:

[0300] In some aspects, the present invention generally comprises: A diaphragm and a transducer base structure; a diaphragm suspension system configured to rotatably mount the diaphragm relative to the transducer base structure such that, in operation, the diaphragm can rotatably vibrate about an axis of rotation relative to the transducer base structure, the axis of rotation of the diaphragm being arranged substantially coaxial with a predetermined nodal axis of the diaphragm; an electromagnetic conversion mechanism operatively coupled to the diaphragm for converting between audio signals and sound pressure, the electromagnetic conversion mechanism comprising a magnetic structure and an associated conductive coil structure disposed in situ within the magnetic field of the magnetic structure, the magnetic structure configured to move during operation; It can be said that the audio transducer is composed of an audio transducer having:

[0301] In some aspects, the present invention generally comprises: A diaphragm and a transducer base structure; a diaphragm suspension system configured to rotatably mount the diaphragm relative to the transducer base structure such that, during operation, the diaphragm can rotatably vibrate about an axis of rotation relative to the transducer base structure; an electromagnetic conversion mechanism operatively coupled to the diaphragm for converting between audio signals and sound pressure, the electromagnetic conversion mechanism comprising a magnetic structure and an associated conductive coil structure disposed in situ within the magnetic field of the magnetic structure, the magnetic structure configured to move during operation, and a shortest distance between the magnetic structure and the conductive coil structure being less than about 1.5 mm; It can be said that the audio transducer is composed of an audio transducer having:

[0302] In some aspects, the present invention generally comprises: A diaphragm and a transducer base structure; a diaphragm suspension system configured to rotatably mount the diaphragm relative to the transducer base structure such that, during operation, the diaphragm can rotatably vibrate about an axis of rotation relative to the transducer base structure; an electromagnetic conversion mechanism operatively coupled to the diaphragm for converting between audio signals and sound pressure, the electromagnetic conversion mechanism comprising a magnetic structure and an associated conductive coil structure disposed in situ within the magnetic field of the magnetic structure, the magnetic structure configured to move during operation; a ferromagnetic shield extending around the transducer mechanism to substantially reduce magnetic attractive or repulsive forces acting on nearby unrelated ferromagnetic material; In some embodiments, the present invention includes a ferromagnetic shield that does not significantly improve the efficiency of the driver (which is not part of the motor).

[0303] In some aspects, the present invention generally comprises: A diaphragm and a transducer base structure; a diaphragm suspension system configured to rotatably mount the diaphragm relative to the transducer base structure such that, during operation, the diaphragm can rotatably vibrate about an axis of rotation relative to the transducer base structure; an electromagnetic conversion mechanism operatively coupled to the diaphragm for converting between audio signals and sound pressure, the electromagnetic conversion mechanism comprising a magnetic structure and an associated conductive coil structure disposed in situ within the magnetic field of the magnetic structure, the magnetic structure configured to move during operation, and the conductive coil structure having a resistance of less than about 2.5 ohms; It can be said that the audio transducer is composed of an audio transducer having:

[0304] In some aspects, the present invention generally comprises: 1. An audio transducer, comprising: A diaphragm and a transducer base structure; a diaphragm suspension system configured to rotatably mount the diaphragm relative to the transducer base structure such that, during operation, the diaphragm can rotatably vibrate about an axis of rotation relative to the transducer base structure; an electromagnetic conversion mechanism operatively coupled to the diaphragm for converting between audio signals and sound pressure, the electromagnetic conversion mechanism comprising a magnetic structure and an associated conductive coil structure disposed in situ within the magnetic field of the magnetic structure, the magnetic structure configured to move during operation; an audio transducer having a housing including an enclosure or baffle for containing an audio transducer; a decoupling mounting system that flexibly mounts the transducer base structure to the housing to at least partially mitigate mechanical transmission of vibrations between the transducer base structure and the housing; It can be said that the audio device is composed of an audio device having the above.

[0305] In some aspects, the present invention generally comprises: A diaphragm and a transducer base structure; a diaphragm suspension system configured to flexibly and rotatably mount the diaphragm to a transducer base structure, the diaphragm suspension system having a pair of flexible mounts coupling between the diaphragm and the transducer base structure, each flexible mount formed from one or more materials having a Young's modulus of less than about 8 GPa; a transducer mechanism operably coupled to the diaphragm for converting between audio signals and sound pressure; It can be said that the audio transducer is composed of an audio transducer having:

[0306] In some aspects, the present invention generally comprises: A diaphragm and a transducer base structure; a diaphragm suspension system configured to flexibly and rotatably mount the diaphragm to a transducer base structure, the diaphragm suspension system having a pair of flexible elements coupled between the diaphragm and the transducer base structure, each flexible element formed from one or more materials having a Young's modulus of less than about 8 GPa, the flexible elements being angled relative to one another; a transducer mechanism operably coupled to the diaphragm for converting between audio signals and sound pressure; It can be said that the audio transducer is composed of an audio transducer having:

[0307] In some embodiments, each flexible element may be configured to undergo large bending deformations to favor fundamental mode diaphragm rotation.

[0308] In some embodiments, the flexible elements are angled at least 40 degrees relative to one another, more preferably at least 50 degrees, and most preferably at least 60 degrees.

[0309] In some embodiments, each flexible element can resist translational motion of the diaphragm along an axis substantially perpendicular to the primary axis of rotation of the diaphragm suspension system by primarily being loaded in tension / compression. Preferably, some directions of translational motion of the diaphragm are perpendicular to the primary axis of rotation, in which case one of the flexible elements is only minimally loaded in tension / compression, while the other flexible elements resist translational motion by being loaded in tension / compression.

[0310] In some embodiments, the flexible elements may be closely spaced, and the pair of flexible elements may be formed as part of a single flexible mount component.

[0311] In some aspects, the present invention generally comprises: A diaphragm and a transducer base structure; a diaphragm suspension system configured to flexibly and rotatably mount a diaphragm relative to a transducer base structure, the diaphragm suspension system having one or more flexible mounts, each flexible mount comprising a substantially longitudinal body having an outer wall and a plurality of internal spokes extending radially toward the outer wall about a longitudinal axis of the body, the internal spokes of each mount being formed from one or more materials having a Young's modulus of less than about 8 GPa so as to flex or deform during operation; a transducer mechanism operably coupled to the diaphragm for converting between audio signals and sound pressure; It can be said that the audio transducer is composed of an audio transducer having:

[0312] In some aspects, the present invention generally comprises: 1. An audio transducer, comprising: A diaphragm and a transducer base structure; a diaphragm suspension system configured to flexibly and rotatably mount the diaphragm to the transducer base structure such that, during operation, the diaphragm can rotatably vibrate about an axis of rotation relative to the transducer base structure, the diaphragm suspension system having one or more flexible mounts, each flexible mount being formed primarily from one or more materials having a Young's modulus of less than about 8 GPa; a transducer mechanism operably coupled to the diaphragm for converting between audio signals and sound pressure; an audio transducer having a housing including an enclosure or baffle for containing an audio transducer; a decoupling mounting system that flexibly mounts the transducer base structure to the housing to at least partially mitigate mechanical transmission of vibrations between the transducer base structure and the housing; It can be said that the audio device is composed of an audio device having the above.

[0313] In some aspects, the present invention generally comprises: 1. An audio transducer, comprising: A diaphragm and a transducer base structure; a diaphragm suspension system configured to rotatably mount the diaphragm relative to the transducer base structure such that, during operation, the diaphragm can rotatably vibrate about an axis of rotation relative to the transducer base structure, the diaphragm suspension system having one or more vibration damping components coupled between the diaphragm and the transducer base structure; a transducer mechanism operably coupled to the diaphragm for converting between audio signals and sound pressure; an audio transducer having a housing including an enclosure or baffle for containing an audio transducer; a decoupling mounting system that flexibly mounts the transducer base structure to the housing to at least partially mitigate mechanical transmission of vibrations between the transducer base structure and the housing; It can be said that the audio device is composed of an audio device having the above.

[0314] In some aspects, the present invention generally comprises: 1. An audio transducer, comprising: A diaphragm and a transducer base structure; a diaphragm suspension system configured to flexibly and rotatably mount the diaphragm to the transducer base structure such that, during operation, the diaphragm can rotatably vibrate about an axis of rotation relative to the transducer base structure, the diaphragm suspension system having one or more flexible mounts, each flexible mount being formed primarily from one or more materials having a Young's modulus of less than about 8 GPa; a transducer mechanism operably coupled to the diaphragm for converting between audio signals and sound pressure; an audio transducer having a housing including an enclosure or baffle for containing an audio transducer; One or more diaphragm stoppers that prevent the diaphragm from being displaced excessively beyond a predetermined maximum displacement to prevent unnecessary movement and damage to the diaphragm. It can be said that the audio device is composed of an audio device having the above.

[0315] In some aspects, the present invention generally comprises: A diaphragm and a transducer base structure; a diaphragm suspension system configured to flexibly and rotatably mount the diaphragm to the transducer base structure such that, during operation, the diaphragm can rotatably vibrate about an axis of rotation relative to the transducer base structure, the diaphragm suspension system having one or more flexible mounts, each flexible mount being formed primarily from one or more materials having a Young's modulus of less than about 8 GPa; a transducer mechanism operably coupled to the diaphragm for converting between audio signals and sound pressure; Equipped with A flexible mount may be said to comprise an audio transducer that provides a primary resistance to translational displacement of the diaphragm mass relative to the transducer base structure in a direction perpendicular to the major surface of the diaphragm body of the diaphragm.

[0316] In some aspects, the present invention generally comprises: A diaphragm and a transducer base structure; a diaphragm suspension system comprising at least one hinge joint for rotatably mounting the diaphragm relative to the transducer base structure such that, during operation, the diaphragm can rotatably vibrate about an axis of rotation relative to the transducer base structure, the hinge joint comprising a material having a loss factor (tan delta characteristic) of greater than 0.005 at 30 degrees Celsius and 100 Hertz; a transducer mechanism operably coupled to the diaphragm for converting between audio signals and sound pressure; Equipped with The hinge joint can be said to comprise an audio transducer that together provide a primary resistance to translational displacement of the vibrating body relative to the transducer base structure along an axis substantially perpendicular to the major surface of the diaphragm body of the diaphragm.

[0317] In some aspects, the present invention generally comprises: a substantially rigid diaphragm body having a first region and a second region, the thickness of the first region being relatively thicker than the thickness of the second region, and the thickness of the second region tapering in a direction away from the first region; a normal stress stiffener coupled to the diaphragm body at or adjacent to at least one major surface of the diaphragm body to resist compressive-tensile stresses experienced by the body during operation; Equipped with The thickness of the first region of the diaphragm body is substantially constant, or a tapered thickness towards the second region that is substantially less steep than the tapered thickness of the second region; or Tapered, thickening towards the second region It can be said that the audio transducer is composed of a diaphragm.

[0318] In some aspects, the present invention generally comprises: a transducer base structure; a diaphragm movably coupled to a transducer base structure, a substantially rigid diaphragm body having a first region and a second region, the thickness of the first region being relatively thicker than the thickness of the second region, and the thickness of the second region tapering in a direction away from the first region; a normal stress stiffener coupled to the diaphragm body at or adjacent to at least one major surface of the diaphragm body to resist compressive-tensile stresses experienced by the body during operation; Equipped with The thickness of the first region of the diaphragm body is substantially constant, or a tapered thickness towards the second region that is substantially less steep than the tapered thickness of the second region; or Tapered, thickening towards the second region A diaphragm, an electromagnetic conversion mechanism operably coupled to the diaphragm and having a magnet or conductive coil rigidly coupled to a first region of the diaphragm body; It can be said that the audio transducer is composed of an audio transducer having:

[0319] In some aspects, the present invention generally comprises: a transducer base structure; a diaphragm movably coupled to a transducer base structure, A substantially rigid diaphragm body having a first region and a second region, the thickness of the first region being relatively thicker than the thickness of the second region, and the thickness of the second region tapering in a direction away from the first region, the thickness of the first region of the diaphragm body being: substantially constant, or a tapered thickness towards the second region that is substantially less steep than the tapered thickness of the second region; or Tapered, thickening towards the second region a diaphragm having a substantially rigid diaphragm body, a diaphragm suspension system configured to rotatably mount a diaphragm relative to a transducer base structure, the diaphragm suspension system being arranged such that a primary axis of rotation of the diaphragm relative to the transducer base structure and a center of mass axis of the diaphragm are substantially coaxial; an electromagnetic conversion mechanism operably coupled to the diaphragm and having a magnet or conductive coil rigidly coupled to a first region of the diaphragm body; It can be said that the audio transducer is composed of an audio transducer having:

[0320] Any one or more of the above embodiments or preferred features may be combined with any one or more of the above aspects.

[0321] Other aspects, embodiments, features and advantages of the present invention will become apparent from the detailed description and accompanying drawings which illustrate, by way of example, the principles of the invention.

[0322] definition The phrase "audio transducer" as used herein is intended to encompass electroacoustic transducers (e.g., loudspeakers, etc.) or acoustoelectric transducers (e.g., microphones, etc.). Although passive radiators are not technically transducers, for purposes of this specification, the term "audio transducer" is also intended to include passive radiators within its definition.

[0323] The phrase "personal audio" as used herein and in the claims with respect to a transducer or device means a loudspeaker transducer or device operable for audio reproduction and sized, intended, and / or specialized for use in close proximity to a user's ear or head during audio reproduction (e.g., within about 10 cm of the user's ear or head). A personal audio device typically includes a sound interface that is sized and configured to be positioned against a user's ear during use. The interface may be mountable, such as in the case of earphones, headphones, or hearing aids, or the interface may be sized to press against the user's ear, such as in the case of mobile phones. The sound interface is preferably smaller than or approximately sized similar to the user's ear. Examples of personal audio transducers or devices include headphones, earphones, hearing aids, and mobile phones.

[0324] The term "comprising," as used in this specification and claims, means "consisting at least in part of." When interpreting each statement in this specification and claims that includes the term "comprising," there may be features present other than the one or more prefaced by that term. Related terms, such as "comprise" and "comprises," should be interpreted in the same manner.

[0325] As used herein, the term "and / or" means either "and" or "or," or both.

[0326] As used herein, "(s)" following a noun refers to the plural and / or singular form of that noun.

[0327] Numeric range Reference to a range of numbers disclosed herein (e.g., 1 to 10) also incorporates a reference to every rational or irrational number within that range (e.g., 1, 1.1, 2, 3, 3.9, 4, 5, 6, 6.5, 7, 8, 9, and 10), and also to any range of rational or irrational numbers within that range (e.g., 2 to 8, 1.5 to 5.5, and 3.1 to 4.7), and therefore all subranges of every range explicitly disclosed herein are intended to be hereby expressly disclosed. These are merely examples of what is specifically intended, and all possible combinations of numerical values ​​between the lowest and highest values ​​recited should be considered to be expressly set forth herein in a similar manner.

[0328] The present invention resides in the foregoing and contemplates constructions of which the following are merely exemplary. Further aspects and advantages of the present invention will become apparent from the following description.

[0329] Preferred embodiments of the present invention will now be described, by way of example only, with reference to the drawings in which: [Brief explanation of the drawings]

[0330] [Figure 1A] 1 is a perspective view of an audio transducer according to a first embodiment of the present invention; [Figure 1B] 1 is a plan view of an audio transducer according to a first embodiment of the present invention. [Figure 1C] 1 is a side cross-sectional view (cross-section GG) of an audio transducer according to a first embodiment of the present invention. [Figure 1D] 1 is a front end view of an audio transducer according to a first embodiment of the present invention. FIG. [Figure 1E] FIG. 2 is an enlarged view of the hinge region of the audio transducer of the first embodiment of the present invention. [Figure 1F] 1 is an exploded perspective view of an audio transducer according to a first embodiment of the present invention. [Figure 1G] 1A-1F show finite element analysis results of a simulation on a model audio transducer similar to the transducer of FIGS. 1A-1F. [Figure 1H] 1A-1F show finite element analysis results of a simulation on a model audio transducer similar to the transducer of FIGS. 1A-1F. [Figure 1I] 1A-1F show finite element analysis results of a simulation on a model audio transducer similar to the transducer of FIGS. 1A-1F. [Figure 2A] 1A to 1F are perspective views of a diaphragm of the diaphragm structure of the audio transducer of FIG. 1A to FIG. 1F. [Figure 2B] 1A to 1F. FIG. [Figure 2C] 1A to 1F. FIG. [Figure 2D]1A-1F is an enlarged view of a hinge region of a diaphragm of the diaphragm structure of the audio transducer of FIG. 1A-FIG. 1F. [Figure 2E] 1A to 1F. FIG. [Figure 2F] 1A to 1F. FIG. 1F is an exploded perspective view of a diaphragm of the diaphragm structure of the audio transducer. [Figure 3A] 1A-1F are perspective views of embodiments of loudspeakers of the present invention that include the audio transducers of FIGS. 1A-1F. [Figure 3B] FIG. 2 is an enlarged view of a region of the protective surround adjacent the front edge of the diaphragm of an embodiment of a loudspeaker of the present invention including the audio transducer of FIGS. 1A-1F. [Figure 3C] 1A-1F is a cross-sectional side view (section CC) of a loudspeaker according to an embodiment of the loudspeaker of the present invention including the audio transducer of FIGS. 1A-1F. [Figure 3D] 1A-1F are top views of embodiments of loudspeakers of the present invention that include the audio transducers of FIGS. 1A-1F. [Figure 3E] 1A-1F is a cross-sectional top view (cross-section II) of an embodiment of a loudspeaker of the present invention including the audio transducer of FIGS. 1A-1F. [Figure 3F] 1A-1F is a close-up view of a protective surround adjacent a side of a diaphragm of an embodiment of a loudspeaker of the present invention including the audio transducer of FIGS. 1A-1F. [Figure 3G] 1A-1F are exploded perspective views of embodiments of loudspeakers of the present invention that include the audio transducers of FIGS. 1A-1F. [Figure 3H] 1A-1F is an enlarged perspective view of the inner wall of a protective surround of a loudspeaker of an embodiment of the loudspeaker of the present invention including the audio transducer of FIGS. 1A-1F. FIG. [Figure 4A] FIG. 1 is an end view of a first embodiment of a flexible mount to be used as a hinge element in the hinge mechanism of the audio transducer of the present invention. [Figure 4B]1 is a side view of a first embodiment of a flexible mount to be used as a hinge element in the hinge mechanism of the audio transducer of the present invention; FIG. [Figure 4C] 1 is a perspective view of a first embodiment of a flexible mount to be used as a hinge element in a hinge mechanism of an audio transducer of the present invention; FIG. [Figure 5A] FIG. 10 is an end view of a second embodiment of a flexible mount to be used as a hinge element in the hinge mechanism of the audio transducer of the present invention. [Figure 5B] 1 is a side view of a second embodiment of a flexible mount to be used as a hinge element in the hinge mechanism of the audio transducer of the present invention. FIG. [Figure 5C] 10 is a perspective view of a second embodiment of a flexible mount to be used as a hinge element in the hinge mechanism of the audio transducer of the present invention. FIG. [Figure 6A] FIG. 10 is an end view of a third embodiment of a flexible mount to be used as a hinge element in the hinge mechanism of the audio transducer of the present invention. [Figure 6B] FIG. 10 is a side view of a third embodiment of a flexible mount to be used as a hinge element in the hinge mechanism of the audio transducer of the present invention. [Figure 6C] 10 is a perspective view of a third embodiment of a flexible mount to be used as a hinge element in the hinge mechanism of the audio transducer of the present invention. FIG. [Figure 6D] 10 is an exploded perspective view of a third embodiment of a flexible mount to be used as a hinge element in the hinge mechanism of the audio transducer of the present invention. FIG. [Figure 7A] FIG. 10 is a perspective view of an audio transducer according to a second embodiment of the present invention. [Figure 7B] 2 is a side cross-sectional view (section AA) of an audio transducer according to a second embodiment of the present invention. [Figure 7C]FIG. 2 is a front end view of an audio transducer according to a second embodiment of the present invention. [Figure 7D] FIG. 4 is a plan view of an audio transducer according to a second embodiment of the present invention. [Figure 7E] FIG. 10 is a close-up cross-sectional view of the transduction mechanism of the audio transducer of the second embodiment of the present invention. [Figure 7F] 1 is a side cross-sectional view (section BB) of an audio transducer according to a second embodiment of the present invention. [Figure 7G] FIG. 10 is a close-up cross-sectional view of the hinge region of an audio transducer according to a second embodiment of the present invention. [Figure 7H] 10 is a cross-sectional view (section D-D) along the hinge of an audio transducer according to a second embodiment of the present invention. [Figure 7I] FIG. 10 is a close-up view of one side of a hinge of an audio transducer according to a second embodiment of the present invention. [Figure 7J] FIG. 10 is an exploded perspective view of an audio transducer according to a second embodiment of the present invention. [Figure 8A] FIG. 8 is an end view of a fourth embodiment of a flexible mount to be used as a hinge element in the hinge mechanism of the audio transducer of FIGS. 7A to 7J. [Figure 8B] FIG. 8 is a side view of a fourth embodiment of a flexible mount to be used as a hinge element in the hinge mechanism of the audio transducer of FIGS. 7A to 7J. [Figure 8C] FIG. 8 is a perspective view of a fourth embodiment of a flexible mount to be used as a hinge element in the hinge mechanism of the audio transducer of FIGS. 7A to 7J. [Figure 9A] FIG. 8 is a perspective view of a diaphragm of the diaphragm structure of the audio transducer of FIGS. 7A to 7J. [Figure 9B] 7A-7J are plan views of the diaphragm of the diaphragm structure of the audio transducer of FIG. 7A-7J. [Figure 9C] 7A-7J is a side view of the diaphragm of the diaphragm structure of the audio transducer of FIG. 7A-7J. [Figure 9D] FIG. 8 is an exploded perspective view of the diaphragm of the diaphragm structure of the audio transducer of FIGS. 7A to 7J. [Figure 10] FIG. 8 is a vector diagram of the potential vector forces experienced by the diaphragm of the audio transducer of FIGS. 7A-7J during operation. [Figure 11] 11 is a vector diagram illustrating the distance between the resulting force vector and the axis of rotation of the diaphragm of FIG. 10. [Figure 12A] FIG. 10 is a perspective view of a third audio transducer embodiment of the present invention. [Figure 12B] FIG. 10 is a side view of a third audio transducer embodiment of the present invention. [Figure 12C] FIG. 2 is a cross-sectional view (section AA) of a third audio transducer embodiment of the present invention. [Figure 12D] FIG. 10 is a close-up cross-sectional view of the edge of the diaphragm of the third audio transducer embodiment of the present invention. [Figure 12E] FIG. 10 is a close-up cross-sectional view of the transduction mechanism of the third audio transducer embodiment of the present invention. [Figure 12F] FIG. 10 is a cross-sectional side view of a third audio transducer embodiment of the present invention (section BB). [Figure 12G] FIG. 10 is a close-up cross-sectional view of the hinge area of ​​a third audio transducer embodiment of the present invention. [Figure 12H] FIG. 10 is a cross-sectional view along the hinge (cross-section CC) of a third audio transducer embodiment of the present invention. [Figure 12I] 10 is a cross-sectional view across the center of a third audio transducer embodiment of the present invention (section DD). [Figure 12J] FIG. 10 is a close-up view of one side of the hinge of the third audio transducer embodiment of the present invention. [Figure 12K] FIG. 10 is an exploded perspective view of a third audio transducer embodiment of the present invention. [Figure 12L]FIG. 10 is a perspective view of a diaphragm structure of a third embodiment of an audio transducer of the present invention. [Figure 12M] FIG. 10 is a front view of a diaphragm structure of a third audio transducer embodiment of the present invention. [Figure 12N] FIG. 10 is a cross-sectional view (section EE) across the diaphragm structure of the third audio transducer embodiment of the present invention. [Figure 12O] FIG. 10 is a cross-sectional view (cross-section FF) taken across the center of the diaphragm structure of the third embodiment of the audio transducer of the present invention. [Figure 12P] FIG. 10 is an exploded perspective view of a diaphragm structure of a third audio transducer embodiment of the present invention. [Figure 13A] FIG. 10 is a perspective view of a fourth audio transducer embodiment of the present invention. [Figure 13B] FIG. 10 is a side view of a fourth audio transducer embodiment of the present invention. [Figure 13C] FIG. 10 is a cross-sectional view (section AA) of a fourth audio transducer embodiment of the present invention. [Figure 13D] FIG. 10 is a close-up cross-sectional view of the edge of the diaphragm of the fourth audio transducer embodiment of the present invention. [Figure 13E] FIG. 10 is a close-up cross-sectional view of the transduction mechanism of the fourth audio transducer embodiment of the present invention. [Figure 13F] FIG. 10 is a cross-sectional side view of a fourth audio transducer embodiment of the present invention (section BB). [Figure 13G] FIG. 10 is a close-up cross-sectional view of the hinge area of ​​a fourth audio transducer embodiment of the present invention. [Figure 13H] FIG. 10 is a cross-sectional view along the hinge (cross-section CC) of a fourth audio transducer embodiment of the present invention. [Figure 13I] 10 is a cross-sectional view across the center of a fourth audio transducer embodiment of the present invention (section DD). [Figure 13J]FIG. 10 is a close-up view of one side of a hinge of a fourth audio transducer embodiment of the present invention. [Figure 13K] FIG. 10 is an exploded perspective view of a fourth audio transducer embodiment of the present invention. [Figure 13L] FIG. 10 is a perspective view of a diaphragm structure of a fourth embodiment of an audio transducer of the present invention. [Figure 13M] FIG. 10 is a front view of a diaphragm structure of a fourth audio transducer embodiment of the present invention. [Figure 13N] 10 is a cross-sectional view (cross-section EE) across the diaphragm structure of the fourth audio transducer of the present invention. [Figure 13O] 10 is a cross-sectional view (cross-section FF) across the center of the diaphragm structure of the fourth embodiment of the audio transducer of the present invention. [Figure 13P] FIG. 10 is an exploded perspective view of a diaphragm structure of a fourth audio transducer embodiment of the present invention. [Figure 14A] FIG. 10 is a perspective view of an audio device incorporating a fourth audio transducer embodiment of the present invention. [Figure 14B] 10 is a cross-sectional view of an audio device incorporating a fourth audio transducer embodiment of the present invention (section HH). [Figure 14C] FIG. 10 is a front view of an audio device incorporating a fourth audio transducer embodiment of the present invention. [Figure 14D] 10 is a cross-sectional view of an audio device incorporating a fourth audio transducer embodiment of the present invention (cross-section GG). [Figure 15A] FIG. 10 is a perspective view of a thin electronic device incorporating a fourth audio transducer embodiment of the present invention. [Figure 15B] FIG. 10 is an exploded perspective view of a thin electronic device incorporating a fourth audio transducer embodiment of the present invention. [Figure 15C]FIG. 10 is a close-up exploded view of a transducer and transducer cavity in a thin electronic device incorporating a fourth audio transducer embodiment of the present invention. [Figure 16A] FIG. 10 is a perspective view of a diaphragm structure of a fifth embodiment of an audio transducer of the present invention. [Figure 16B] FIG. 10 is a cross-sectional side view of a fifth audio transducer embodiment of the present invention. [Figure 16C] FIG. 10 is a close-up cross-sectional view of a hinge of a fifth audio transducer embodiment of the present invention. [Figure 17A] FIG. 10 is a perspective view of another hinge mount embodiment of the present invention. [Figure 17B] FIG. 10 is a close-up view of the end of another hinge mount embodiment of the present invention. [Figure 18A] FIG. 10 is a perspective view of another hinge mount embodiment of the present invention. [Figure 18B] FIG. 10 is a close-up view of the end of another hinge mount embodiment of the present invention. [Figure 19A] FIG. 10 is a perspective view of another hinge mount embodiment of the present invention. [Figure 19B] FIG. 10 is an end view of another hinge mount embodiment of the present invention. [Figure 19C] FIG. 2 is a cross-sectional view of another hinge mount embodiment of the present invention (section XX). [Figure 20A] 1 is a perspective view of a headphone device incorporating an embodiment of an audio transducer of the present invention; [Figure 20B] 1 illustrates a headphone device incorporating an embodiment of the audio transducer of the present invention, and is an exploded perspective view of one of the headphone interfaces. FIG. [Figure 21A] FIG. 1 is a block diagram illustrating an audio system embodiment of the present invention incorporating an audio tuning system and any one or more of the audio transducer embodiments of the present invention. [Figure 21B]FIG. 1 is a block diagram illustrating an audio system embodiment of the present invention that incorporates an audio tuning system within a sound source device. [Figure 22A] 1 is a flowchart of a first method for assembling or manufacturing any of the audio transducer embodiments of the present invention. [Figure 22B] 10 is a flowchart of a second method for assembling or manufacturing any of the audio transducer embodiments of the present invention. [Figure 22C] 10 is a flowchart of a third method for assembling or manufacturing any of the audio transducer embodiments of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0331] Various audio transducer embodiments of the present invention will now be described with reference to the figures. In each of the audio transducer embodiments described herein, the audio transducer includes a diaphragm structure movably coupled to a base (e.g., a transducer base structure and / or a portion of a housing, support, or baffle, etc.). The base has a relatively higher mass than the diaphragm structure. A transduction mechanism associated with the diaphragm structure moves the diaphragm structure in response to electrical energy in the case of an electroacoustic transducer, or converts the movement of the diaphragm structure into electrical energy in the case of an acoustoelectric transducer. Herein, the transduction mechanism may also be referred to as an excitation mechanism. One part or side of the transduction mechanism may be coupled to the base (the "base-side transduction component" or "transducer base structure-side transduction component"), and another side or part of the transduction mechanism may be coupled to the diaphragm structure (the "diaphragm-side transduction component").

[0332] In some embodiments, the transducer can include an electromagnetic transduction mechanism. The electromagnetic transduction mechanism typically includes a magnet or magnetic structure configured to generate a magnetic field and at least one conductive coil (referred to herein as a "coil") configured to be positioned within the magnetic field and to move in response to a received electrical signal (in the case of an electroacoustic transducer) or to generate an electrical signal in response to movement (in the case of an acoustoelectric transducer). Because the electromagnetic transduction mechanism does not require a physical connection between the magnet and the coil, one part of the mechanism will generally be coupled to the base and another part of the mechanism will be coupled to the diaphragm structure. In some embodiments, the magnet is coupled to or forms part of the transducer base structure, and the coil is coupled to or forms part of the diaphragm structure. In other embodiments, the magnet is coupled to or forms part of the diaphragm structure, and the coil is coupled to or forms part of the transducer base structure. In alternative embodiments, other transduction mechanisms (e.g., piezoelectric, electrostatic, or other suitable mechanisms known in the art) may be incorporated into the audio transducer embodiments described herein.

[0333] In some embodiments, the diaphragm structure can include a single diaphragm. In some embodiments, the diaphragm structure can include multiple diaphragms including multiple diaphragm bodies extending from a central base region. The multiple diaphragms can be linked and can be movable simultaneously during operation.

[0334] The diaphragm structure is movably coupled to the base via a diaphragm suspension. In embodiments of the rotary action audio transducer, the diaphragm rotatably rocks relative to the base. In the rotary action audio transducer, the diaphragm suspension includes a hinge configured to rotatably couple the diaphragm structure to the base. In some embodiments, the diaphragm suspension can allow linear movement of the diaphragm structure relative to the base.

[0335] The audio transducer may be housed within a housing or surround to form an audio transducer assembly, which may also form an audio device or part of an audio device (e.g., part of an earphone or headphone device that may include multiple audio transducer assemblies). In some embodiments, the transducer base structure may form part of the housing or surround of the audio transducer assembly. The audio transducer, or at least the diaphragm structure, is mounted to the housing or surround via a decoupling mounting system. As described in PCT / IB2016 / 055472, types of mounting systems configured to decouple the audio transducer from the housing or surround to at least reduce the transmission of mechanical vibrations from the audio transducer to the housing (or vice versa) due to unwanted resonances during operation may be utilized in any one of the embodiments of the present invention.

[0336] While the various structures, assemblies, mechanisms, devices, or systems described under these sections are described in connection with some of the audio transducer embodiments of the present invention, it will be understood that these structures, assemblies, mechanisms, devices, or systems may alternatively be incorporated into any other suitable audio transducer assemblies without departing from the scope of the present invention. Moreover, audio transducer embodiments of the present invention incorporate specific combinations of one or more of the various features, structures, assemblies, mechanisms, devices, or systems that may be incorporated in other combinations with respect to alternative embodiments.

[0337] Methods of constructing audio transducers, audio devices, or any of the various structures, assemblies, mechanisms, devices, or systems are described herein with respect to some, but not all, embodiments for the sake of brevity. Application of such methods to other embodiments is not intended to exclude the scope of the invention. Additionally, the invention is intended to cover methods of transducing audio signals using the principles of operation and / or audio transducer features described herein.

[0338] Embodiments or configurations of an audio transducer or related structure, mechanism, device, assembly, or system of the present invention are described herein with reference to an electroacoustic transducer, such as a loudspeaker driver, etc. Unless otherwise stated, an audio transducer or related structure, mechanism, device, assembly, or system described herein may otherwise be implemented as or in an acoustoelectric transducer, such as a microphone, etc. As such, the term audio transducer as used herein is intended to include both electroacoustic (e.g., loudspeaker) and acoustoelectric (e.g., microphone) implementations, unless otherwise stated.

[0339] 1. First Audio Transducer Embodiment 1A-1F, a first embodiment of a rotary-action audio transducer 100 of the present invention is shown including a diaphragm A101 rotatably coupled to a transducer base structure A102 via a substantially flexible diaphragm suspension. The diaphragm A101 is a single body structure, but alternatively, in some embodiments, may include multiple diaphragm body structures. The diaphragm A101 is operably coupled to a transduction mechanism configured to convert electrical audio signals into rotational motion of the diaphragm A101. In this embodiment, the transduction mechanism is an electromagnetic mechanism including a conductive coil A106 and a magnet A205. Unless otherwise specified, the term magnet can refer to one or more permanent magnets, or one or more direct current electromagnets, or any combination thereof. In this embodiment, the magnet is a permanent magnet A205. Unless otherwise specified, the terms "conductive coil" or "coil" as used herein can include single or multiple coil windings. In this embodiment, the conductive coil A106 is coupled to the base structure A102 and the magnet A205 is coupled to the diaphragm A101. In an alternative configuration, this may be reversed.

[0340] The diaphragm suspension flexibly and rotatably mounts the diaphragm A101 relative to the transducer base structure A102. The diaphragm suspension includes one or more flexible hinge mounts A107a,b configured to allow rotation of the diaphragm A101 relative to the transducer base structure A102 about the primary axis of rotation A103 via the mount's flexures. The flexible mounts A107a,b are flexible in terms of rotational movement about one or more orthogonal axes and / or translational movement along one or more orthogonal axes. This results in a compliant diaphragm suspension, which allows movement of the diaphragm relative to the transducer base structure in directions other than the primary axis of rotation A103. The degree of compliance can vary depending on the direction of the applied force. The diaphragm suspension is preferably compliant in translation and rotation. The diaphragm suspension system is preferably substantially compliant in terms of translation along one or more axes, the one or more axes including: substantially perpendicular to the main radiation plane A212a / A212b and / or the coronal plane A211 of the diaphragm A101; substantially parallel to the main faces A212a / A212b and / or the coronal plane A211 of the diaphragm A101 and substantially perpendicular to the main axis of rotation A103; and / or · Substantially parallel to the main rotation axis A103.

[0341] The diaphragm suspension can be compliant along any combination of one or more of the above-mentioned axes, more preferably any combination of two or more, and most preferably any combination of all three. The diaphragm suspension is preferably compliant in terms of rotation about the primary axis of rotation A103 and one orthogonal axis, more preferably two other orthogonal axes. The diaphragm suspension can also include stops or other limiters to limit displacement of the diaphragm relative to the transducer base structure in one or more directions. A flexible hinge mount preferably provides primary compliance with respect to diaphragm rotation during operation. The diaphragm suspension also provides primary resistance to movement / displacement of the diaphragm relative to the transducer base structure in the above-mentioned directions during normal use (in addition to the above-mentioned stops or limiters, which prevent rather than resist further movement).

[0342] In some cases, if there are diaphragm resonant modes associated with translational compliance at the hinges, it is the compliance of the diaphragm suspension that primarily influences the frequencies of such modes, while other elements such as stops and torsion bars may not significantly influence such frequencies. In this application, hinge translational compliance in the direction perpendicular to the coronal plane of the diaphragm is of interest in some cases, because such resonances can generate a significant amount of sound due to the fact that a large diaphragm area can move in a direction that couples with the air.

[0343] In this embodiment, the suspension system includes a pair of substantially flexible mounts A107a and A107b on either side of the diaphragm A101. The flexible mounts are preferably coupled to opposite outer sides of the diaphragm A101 along the major axis A103 and on either side of the sagittal plane A201 of the diaphragm. The flexible mounts A107a and A107b are preferably formed from a substantially flexible and resilient material.

[0344] Each mount A107a, A107b is preferably formed from a substantially flexible material. Each substantially flexible hinge mount A107a, A107b is preferably substantially compliant in translation, allowing the hinge mount to deform substantially linearly along at least one axis, preferably along at least two orthogonal axes, and most preferably along three orthogonal axes. In this embodiment, for example, an elastomer or flexible plastic material may be used.

[0345] Each hinge mount A107a, A107b is preferably formed from a material (referred to herein as a "damped material" or "damped hinge mount") that provides damping in terms of translational displacement along at least one axis, more preferably along at least two orthogonal axes, and most preferably along at least three orthogonal axes. In this embodiment, for example, an elastomer or soft plastic material may be used.

[0346] As used herein, in the context of a hinge or hinge mount for an audio transducer diaphragm or diaphragm structure, the terms "soft" and "flexible" in terms of the materials used are intended to mean one or more materials having an overall Young's modulus of less than about 8 gigapascals (GPa), less than about 4 GPa, less than about 2 GPa, less than 1.5 GPa, less than 1 GPa, or less than 0.1 GPa.

[0347] Typically, such Young's modulus values ​​will be sufficiently low that approaches that push the resonant modes associated with the hinge compliance outside the operating bandwidth in terms of frequency may not be possible, and the design approach will be one of either managing such resonances within the operating bandwidth or taking the opposite approach of shifting them below the operating bandwidth in terms of frequency.

[0348] These values ​​are also low enough that the material can be well damped, which can be advantageous for managing resonances associated with hinge compliance. Each hinge mount A107a, A107b is preferably formed from a well damped material such that it has a material loss factor at 30 degrees Celsius and 100 Hertz operating frequency of greater than 0.005, greater than about 0.01, greater than about 0.02, or greater than about 0.05.

[0349] In this embodiment, each mount A107a, A107b can include one or more main bodies formed from a thermosetting urethane elastomer (e.g., one having a Shore A hardness of between 50 and 70). Such a material can include, for example, a Young's modulus of between about 6 MPa and about 100 MPa. In some embodiments, each mount can be formed from silicone rubber or nitrile rubber. Preferably, each mount is formed primarily from a material having a combination of one or more of the following properties: the ability to be attached to a support, such as via adhesive or overmolding; resistance to long-term creep under loads, such as gravity and / or magnetic attraction; the ability to withstand sufficient cycles and deformation over a range of temperatures during use; and sufficient resistance to changes in properties (e.g., stiffness and damping) over time or with changes in temperature. Each mount A107a, A107b preferably exhibits all of the above properties. Each mount A107a, A107b can be formed from a molding process, such as injection molding.

[0350] In some embodiments, each hinge mount A107a, A107b has a sufficiently low Young's modulus such that the fundamental diaphragm resonant frequency is less than about 100 Hertz, less than about 70 Hertz, or less than about 50 Hertz.

[0351] The diaphragm A101 is of a substantially rigid construction, for example, as described in WO 2017 / 046716. Similarly, the transducer base structure is substantially rigid and includes a relatively squat geometry, for example, as described in WO 2017 / 046716.

[0352] The diaphragm suspension, including flexible hinge mounts A107a and A107b, forms a hinge that allows the diaphragm A101 to rotatably swing relative to the transducer base structure A102 about the axis of rotation A103. The locations of the mounts A107a and A107b are chosen so that the axis of rotation A103 coincides with the nodal axis A104 of the diaphragm A101. The nodal axis A104 can be determined in advance or during device manufacturing / installation. The diaphragm nodal axis A104 depends primarily on the mass distribution of the diaphragm A101 and the force vectors the diaphragm experiences from the translation mechanism during operation. As will be explained in more detail below, the diaphragm nodal axis A104 is the major axis about which the diaphragm A101 will rotate if it were effectively substantially unsupported and subjected to the same forces applied by the translation mechanisms A106 / A205.

[0353] In this embodiment, the translation mechanism is designed so that the nodal axis A104 of the diaphragm A101 is substantially coaxial with the central axis of the diaphragm A101 (also A104 in this embodiment). Notably, in this embodiment, the translation mechanism is configured to apply a substantially pure torque having an approximately zero translational force vector applied to the diaphragm A101 during operation. In this manner, and as will be explained in more detail below, this positions the nodal axis A104 of the diaphragm A101 at or substantially proximal to the central axis of the diaphragm A101. Moreover, in this embodiment, the diaphragm A101 is designed so that the central axis of the mass A104 is located proximal to one end of the diaphragm A101.

[0354] Each hinge mount A107a, A107b of the diaphragm suspension provides a primary hinge support to the diaphragm for rotationally coupling the diaphragm to the transducer base structure. A primary hinge support may refer to a hinge that significantly contributes to the stiffness of the support in a direction perpendicular to the axis of rotation and perpendicular to the coronal plane of the diaphragm, such that when the translational compliance of the diaphragm suspension is changed in this direction, there is a corresponding and significant change in the frequency of one or more primary resonant modes with translation of the diaphragm proximal to said hinge support.

[0355] 3A-3H, in some configurations, audio transducer A100 may be housed within speaker enclosure A301 / A302 and is preferably decoupled from speaker enclosure A301 / A302 via a decoupling mounting system, for example, as described in PCT publication WO 2017 / 046716, section 4. Enclosure A301 / A302 preferably includes ferromagnetic mesh shielding A308 to substantially prevent magnetic interaction between audio transducer A100 and other foreign objects external to the speaker.

[0356] Various preferred and alternative features of audio transducer A100 and associated speaker systems will now be described in further detail.

[0357] Transducer Base Structure 1A-1F, the transducer base structure A102 includes a main body A110 and a conductive coil A106 of the transduction mechanism. The conductive coil A106 is preferably rigidly coupled to the main body A110 at one end of the body. The transducer base structure A102 further includes a pair of decoupling pins A111a, A111b of a decoupling mounting system and a pair of diaphragm suspension blocks A109a, A109b configured to cooperate with the flexible mounts A107a, A107b and pins A108a, A108b of the diaphragm suspension system, respectively. The main body A110 includes cooling fins A110a to help cool the conductive coil A106 and increase power handling. The main body A110 also has internal ribs A110b, which provide rigidity.

[0358] The base structure A102 is relatively squat and formed from a relatively high specific modulus material (e.g., greater than about 30 GPa), and therefore has internal resonant modes with high frequencies (preferably outside the hearing range of a listener and / or the frequency range of the intended operation of the transducer).

[0359] The main body A110 has an aperture A110c on each side to receive, secure, and accommodate a driver decoupling pin A111 of a decoupling mounting system. The decoupling pin A111 may be secured to the main body via adhesive or other suitable mechanism. The apertures A110c on each side of the main body A110 are preferably substantially coaxial with the transducer's nodal axis A105 (hereinafter referred to as the transducer nodal axis A105). This helps to provide effective decoupling of the audio transducer A100 to the housing A301 / A302, as described, for example, in WO 2017 / 046716 with respect to embodiment A.

[0360] The conductive coil A106 is rigidly coupled to the transducer base structure body and may be wound in an approximately rectangular shape (e.g., clockwise as viewed in FIG. 1D) using enamel-coated copper wire.

[0361] The coil A106 includes recesses A106a, A106b on the inner periphery of opposite short sides for fixedly receiving mounting blocks A109a, A109b, respectively, of a diaphragm suspension system.

[0362] The transducer base structure of this embodiment may alternatively be replaced by the transducer base structure of any one of the other embodiments described herein.

[0363] diaphragm structure 2A-2F, in this embodiment, the diaphragm A101 includes a structure including a main diaphragm body A207 and a magnet A205 of a translation mechanism, with the magnet A205 connected to one end of the body A207 at a base region A101a of the diaphragm A101. A pair of diaphragm mounting pins A108a and A108b of the diaphragm suspension extend laterally from either side of the magnet A205. The diaphragm A101 is a rigid diaphragm construction comprising a magnet A205, a pin A108, a plurality of body parts A208a-A208k, inner reinforcing members A209a-A209j between each adjacent pair of body parts A208a-A208k, and outer reinforcing members A206a, A206b extending over or adjacent to each major surface A212a, A212b of the diaphragm body A207. The diaphragm body parts A208a-k, inner reinforcing members A209a-A209j, and outer reinforcing members A206a, A206b are substantially rigid and are formed, for example, according to the rigid diaphragm construction principles described in WO2017 / 046716.

[0364] The diaphragm body A207 can include an interconnected structure that varies in three dimensions. The body A207 can include a substantially low-density matrix and can be formed, for example, from expanded polystyrene foam body parts A208a-A208k.

[0365] The inner stiffeners A209a-A209j may be substantially thin and formed from aluminum foil and laminated between the body parts A208a-A208k. The outer stiffeners A206a, A206b may include a plurality of struts made from carbon fiber or other suitably stiff material (most preferably with a Young's modulus greater than about 900 GPa). The outer stiffeners may be sandwiched over the two outer primary radiating surfaces A212a, A212b of the diaphragm body A207.

[0366] The diaphragm body A207 includes a maximum thickness greater than 12% or, more preferably, greater than 15% of the length of the diaphragm body A207. The diaphragm body A207 can, in some embodiments, include a maximum thickness greater than 20% of the length of the diaphragm body. Alternatively or additionally, the diaphragm body A207 can include a maximum thickness greater than 9% or greater than 11% of the maximum dimension (e.g., diagonal length, etc.) of the diaphragm body A207. The diaphragm body A207 can, in some embodiments, include a maximum thickness greater than 14% of the maximum dimension (e.g., diagonal length, etc.) of the diaphragm body A207.

[0367] The diaphragm A101 can include a length from the axis of rotation to the opposing terminal end, which length is less than about six times the width of the diaphragm or diaphragm structure, or less than four times its width, or less than three times its axial width.

[0368] The diaphragm A101 includes a mass that varies along its length. The diaphragm A101 includes a relatively lower mass per unit area in regions of the diaphragm distal from the center of mass A104 of the diaphragm A101 than in regions proximal to the center of mass A104. In this embodiment, the diaphragm A101 also includes a lower mass per unit area in regions of the diaphragm distal from the axis of rotation A103 of the diaphragm than in regions proximal to the axis of rotation A103. The diaphragm also includes a relatively lower mass per unit area in regions proximal to one end of the diaphragm than in regions proximal to the opposite end.

[0369] In this embodiment, the diaphragm body A207 is configured with a thickness profile that varies along the length of the diaphragm. As shown in FIG. 2C, the diaphragm body A207 is configured with a relatively greater thickness in a first region A114a at or near the base region relative to a second region A114b distal from the base region. The thickness in the second region is preferably substantially tapered, decreasing away from the base region. The thickness in the first region A114a is substantially constant or tapers with a slope that is substantially less than the slope or taper of the second region A114b. The overall major surface profile can be linear and / or substantially curved. In this embodiment, the profile is substantially curved. The major surface profile is generally convex along the length of the surface. In other words, the major surface profile is generally convex along a sagittal cross section of the diaphragm body A207.

[0370] In this embodiment, normal stress stiffeners A206a, A206b comprise a relatively lower mass per unit area in regions of the diaphragm distal to the center of mass A104 of the diaphragm A101 relative to regions proximal to the center of mass A104. In some embodiments, the regions of relatively lower normal stress stiffener mass can comprise recesses or can be devoid of normal stress stiffeners. In this embodiment, the regions of relatively lower normal stress stiffener mass comprise normal stress stiffeners of reduced or decreasing thickness, reduced or decreasing width, or both.

[0371] The area of ​​the relatively higher normal stress stiffening mass and / or higher diaphragm mass comprises approximately 30-70% of the surface area of ​​the main face, and the area of ​​the relatively lower normal stress stiffening mass and / or lower diaphragm mass comprises approximately 70-30% of the surface area of ​​the main face.

[0372] In some embodiments, the region of relatively lower normal stress reinforcement mass and / or lower diaphragm mass may be located within about 20% of the length of the diaphragm from the end of the diaphragm that is distal from the center of mass or distal from the axis of rotation, in the case of a rotary diaphragm.

[0373] In this embodiment, the diaphragm A101 is substantially symmetrical with respect to the sagittal plane of the diaphragm. The diaphragm structure, including the diaphragm body A207 and the magnet A205 of the transducer mechanism, is substantially symmetrical with respect to the sagittal plane of the diaphragm A101.

[0374] In some embodiments, it is preferred that diaphragm A101 does not include position sensors or other unnecessary weighted elements that may exacerbate resonance problems or otherwise adversely affect operation.

[0375] The diaphragm A101 of this transducer embodiment may alternatively be replaced by the diaphragm of any one of the other embodiments described herein, and similarly, the diaphragm A101 may be used in any one of the audio transducer embodiments described herein.

[0376] Conversion mechanism The conversion mechanism in this embodiment includes an electromagnetic mechanism including a coil, the coil being operably coupled to a magnet. Preferably, the conversion mechanism is substantially non-commutated.

[0377] In each of the embodiments described herein, the transduction mechanism generally includes a diaphragm-side transduction component, which in this case is a magnet A205. As used herein, the phrase "diaphragm-side transduction component" is intended to mean a part of the transduction mechanism that is coupled to the diaphragm or diaphragm structure, which is responsible for converting electrical energy to mechanical energy (or vice versa). For example, this can be a coil or magnet of an electromagnetic mechanism, or it can be a part, section, or component of a piezoelectric mechanism.

[0378] The transduction mechanism also typically includes a base structure transduction component, which in this case is coil A106. As used herein, the phrase "base structure transduction component" is intended to mean a portion of the transduction mechanism that is coupled to the transducer base structure, the transducer base structure being configured to remain substantially stationary relative to the diaphragm during operation. For example, this could be a stationary coil or magnet of an electromagnetic mechanism, or it could be a stationary part, section, or component of a piezoelectric mechanism.

[0379] In this embodiment, the diaphragm-side transduction component A205 is directly coupled to the diaphragm A101, preferably rigidly coupled thereto. The magnet A205 is integrated into the diaphragm A101 so that it is a single structure. The magnet A205 includes an outer surface configured to couple to a corresponding surface of the diaphragm body A207. The outer surface and the corresponding surface are complementary. In this embodiment, the outer surface is substantially planar, and the corresponding diaphragm surface is substantially planar. However, other profiles are possible.

[0380] In some embodiments, the diaphragm-side transduction component may be indirectly coupled to the diaphragm or diaphragm structure via one or more intermediate components. The one or more intermediate components are preferably substantially rigid, and may include, for example, a Young's modulus of at least about 8 GPa or at least about 20 GPa. In some embodiments, the diaphragm or diaphragm structure may be rigidly coupled to the transduction mechanism via one or more substantially planar parts or components. When the diaphragm is coupled to the diaphragm-side transduction component via one or more intermediate components, in some embodiments, the components may be sufficiently straight and / or sufficiently supported and / or sufficiently thick to minimize bending deformation of the one or more rigid components.

[0381] Referring to FIGS. 2A, 2C, and 2D, the magnet A205 is magnetized in a direction perpendicular to the coronal plane A211 of the diaphragm A101. The magnet's poles are located on opposite sides of the rotation axis A103 to achieve this. In some embodiments, the poles can be arranged so that the primary internal magnetic field is angled with respect to the rotation axis A103 and / or the coronal plane A211. The magnet includes a substantially non-alternating magnetic field. The magnet is preferably a permanent magnet, such as an N52 grade neodymium (NdFeB) magnet, or another strong permanent magnet type. Alternatively, the magnet can be an electromagnet. The electromagnet is preferably a direct current electromagnet. Preferably, the magnet is not an armature. The magnet A205 can exhibit high magnetic strength, sufficient physical strength, and toughness to survive potential shock scenarios over the life of the transducer and / or the relatively low density of the magnet. Other grades of magnets offering improved resistance to elevated temperatures may also be used depending on power handling and other operating requirements.

[0382] The magnet A205 is located at or proximal to the rotation axis A103 of the diaphragm A101. The magnet A205 is located on either side of or proximal to the diaphragm's rotation axis A103 with respect to the sagittal plane A201 of the diaphragm A101. The magnet A205 is coupled along an axis substantially parallel to the rotation axis A103 or the center of mass axis A104. The magnet A205 extends along the rotation axis A103, which in this embodiment extends through the magnet A205. In some variations, the magnet A205 may be located proximal to the rotation axis, but is substantially exclusively proximal to the rotation axis A103, such that no other parts or components of the diaphragm-side translation mechanism are proximal to the axis. For example, the magnet A205 may be located within 50% of the length of the diaphragm A101 from the axis of rotation A103, or within 40% of the length of the diaphragm from the axis of rotation, or most preferably within 30% of the length of the diaphragm from the axis of rotation. In some embodiments, the magnet A205 may be located within 20% of the maximum length dimension (e.g., diagonal length dimension) of the diaphragm from the axis of rotation, or within 15% of the maximum length dimension from the axis of rotation, or most preferably within 10% of the maximum length dimension from the axis of rotation.

[0383] The magnet A205 does not extend beyond the maximum width of the diaphragm A101 or diaphragm body A207. In some embodiments, the magnet A205 can extend beyond the width, but preferably extends more than about 20%, more than about 15%, or most preferably more than about 10% of the width dimension along the axis of rotation A103. The maximum width dimension in this case can be substantially parallel to the axis of rotation A103.

[0384] In this embodiment, the magnet A205 is coupled to the edge of the diaphragm A101 and extends longitudinally along the edge between both sides of the diaphragm. Because the magnet A205 has a high specific modulus of elasticity and a reasonably stiff geometry, the magnet A205 provides a suitably low-resonance base upon which the relatively lightweight diaphragm body A207 is supported, resulting in a relatively large diaphragm A101 with a breakup mode that occurs at a relatively high frequency. Rotational inertia is manageable due to the fact that the magnet's mass is concentrated near the axis of rotation A103. The magnet A205 is shaped to have a slightly higher mass on the side A205a distal to the diaphragm body A207 relative to the mass on the side A205b directly adjacent to the diaphragm body A207. This is achieved by shaping the periphery of the magnet A205 on the distal side. The mass profile of magnet A205 is predetermined to locate center of mass axis A104 at a desired location (preferably closer to terminal end A101a of the diaphragm), and the magnet is symmetrical about a plane that is substantially perpendicular to the axis of rotation or substantially perpendicular to the longitudinal axis of the diaphragm.

[0385] The magnet A205 is configured to cooperate with a coil A106, which is rigidly coupled to the transducer base structure A102, to exert a substantially pure mechanical torque on or transfer a substantially pure mechanical torque from the diaphragm A101. The coil A106 may include a single winding extending around the periphery of the magnet A205. In this embodiment, the coil A106 is not in intimate contact with any ferromagnetic core or other ferromagnetic components.

[0386] In use, an audio signal (from an amplifier) ​​can be applied to the conductive coils, which in turn apply positive and negative torque to the magnets and rotate the diaphragm about the axis of rotation A103. Preferably, the conductive coils A106 extend substantially parallel to and along either side of the axis of rotation A103. Preferably, the conductive coils A106 extend in a plane substantially transverse to the longitudinal axis A211a of the diaphragm A101.

[0387] In this embodiment, separating the coil A106 from the diaphragm A101 means that the mass of the coil A106 can be increased without adversely affecting efficiency. In many cases, increasing mass can improve the device's power handling and improve efficiency by facilitating an increase in wire turns for a given direct current (DC) coil resistance. However, increasing the turns can create different efficiency limitations associated with coil inductance, which can block current at high frequencies. To minimize this effect, the wire used in the conductive coil A106 preferably has a substantially larger diameter for a given volume, reducing the number of turns in the coil A106, thereby reducing coil inductance and resulting in a sound pressure response of the transducer A100 that has relatively little drop-off with increasing frequency. In this way, the DC resistance of the coil A106 can be reduced below standard (approximately in the range of 3 to 7 ohms). The DC resistance of coil A106 can be less than about 2.5 ohms, less than about 2 ohms, less than about 1.5 ohms, or less than about 1 ohm. In this embodiment, the DC resistance of coil A106 can be, for example, about 0.6 ohms.

[0388] Magnet A205 and coil A106 are separated by an air-fluid gap. In this embodiment, the fluid gap is an air gap. Alternatively, a ferromagnetic fluid or material may be located between the coil and magnet. The magnet may include a substantially curved surface adjacent to the fluid gap. Also, coil A106 may include a complementary curved surface adjacent to the air-fluid gap and magnet A205. The curved surfaces of the coil and magnet may be complementary. The magnet surface may be curved about the axis of rotation. Also, the coil surface may be curved about the axis of rotation.

[0389] Conductive coil A106 extends in situ around magnet A205. Preferably, the shortest distance between magnet A205 and conductive coil A106 is less than about 1.5 mm, less than about 1 mm, or less than about 0.5 mm. Preferably, conductive coil A106 is symmetrical on both sides of magnet A205.

[0390] The conversion mechanism of this embodiment may alternatively be replaced with the conversion mechanism of any one of the other embodiments or variations described herein.

[0391] The magnet is well away from other ferromagnetic components In embodiments of the present invention, the audio transducer may include ferromagnetic components other than the transduction mechanism or other than those that may be rigidly coupled to the magnet as part of the magnetic assembly (i.e., the magnetic poles), or other than those that may be rigidly coupled to the magnet or magnetic assembly to couple the magnetic assembly to the diaphragm or transducer base structure. Such other ferromagnetic components may have substantially strong ferromagnetic properties. Substantially strong ferromagnetic properties in this context are on the order of about 300 mμ. r or about 500 mμ r or greater than about 1000 mμ rThis can mean that the diaphragm has a maximum relative permeability in situ (with the diaphragm at rest) that is greater than

[0392] The inclusion of such components in an audio transducer means that there will be attractive forces on the magnet exerted by such components unless they are located substantially distal to the magnet or magnet assembly. In the case of this embodiment where the magnet is coupled to a substantially compliant diaphragm suspension, this can cause the suspension to lose its integrity over time. In other embodiments, plastic housings and mounts may be susceptible to creep deformation when subjected to long-term loading due to magnetic attractive forces.

[0393] For this reason, this and other embodiments of the present invention are preferably configured such other ferromagnetic components to be located substantially distal from the magnet or magnetic structure so that only a relatively small pulling force exists on the magnet, or, in the case of multiple components acting on the magnet in multiple directions, so that a negligible or near-zero net force exists on the magnet.

[0394] For example, in some embodiments, the other ferromagnetic component may include one or more relatively large or major surfaces that face the magnet or magnetic structure or assembly. If such surfaces are located proximate to the magnet, they will typically exert a significant force on the magnet. Preferably, such surfaces are substantially distal from the nearest or relatively large or major surfaces of the magnet to reduce or significantly minimize or reduce the attractive forces from the other ferromagnetic component on the magnet or magnetic structure or assembly.

[0395] The following are examples of "substantially distal in this context":

[0396] The nearest or larger or major surface of a magnet or magnetic structure or assembly may be separated from the larger or major surface of another ferromagnetic component by a minimum or average distance of at least about 0.4 times the maximum distance between opposing magnetic poles of the magnet assembly or magnetic structure or assembly. The nearest or larger or major surface of a magnet or magnetic structure or assembly may be separated from the larger or major surface of another ferromagnetic component by a distance of at least about 0.6 times the maximum distance between opposing magnetic poles of the magnet or magnetic structure or assembly. The nearest or larger or major surface of a magnet or magnetic structure or assembly may be separated from the larger or major surface of another ferromagnetic component by about the same distance as the distance between opposing magnetic poles of the magnet or magnetic structure or assembly.

[0397] The nearest or relatively large or major surface of a magnet or magnetic structure or assembly may be separated from the relatively large or major surface of another ferromagnetic component along an axis substantially perpendicular to the axis of rotation by a distance of at least about 0.4 times the maximum distance between opposing magnetic poles of the magnet or magnetic structure or assembly. The nearest or relatively large or major surface of a magnet or magnetic structure or assembly may be separated from the relatively large or major surface of another ferromagnetic component along an axis substantially perpendicular to the axis of rotation by a distance of at least about 0.6 times the maximum distance between opposing magnetic poles of the magnet or magnetic structure or assembly. The nearest or relatively large or major surface of a magnet or magnetic structure or assembly may be separated from the relatively large or major surface of another ferromagnetic component along an axis substantially perpendicular to the axis of rotation by about the same distance as the distance between opposing magnetic poles of the magnet or magnetic structure or assembly.

[0398] The nearest or larger or main surface of a magnet or magnetic structure or assembly may be separated from the nearest or larger surface of another ferromagnetic component by a distance of at least about 0.4 times the largest dimension of the magnet along an axis substantially perpendicular to the axis of rotation. The nearest or larger or main surface of a magnet or magnetic structure or assembly may be separated from the nearest or larger surface of another ferromagnetic component by a distance of at least about 0.6 times the largest dimension of the magnet along an axis substantially perpendicular to the axis of rotation. The nearest or larger or main surface of a magnet or magnetic structure or assembly may be separated from the nearest or larger surface of another ferromagnetic component by a distance about the same as the largest dimension of the magnet along an axis substantially perpendicular to the axis of rotation.

[0399] The nearest or larger or main surface of a magnet or magnetic structure or assembly may be separated from the larger or main surface of another ferromagnetic component by a distance of at least about 0.4 times the maximum length of the magnet. The nearest or larger or main surface of a magnet or magnetic structure or assembly may be separated from the larger or main surface of another ferromagnetic component by a distance of at least about 0.6 times the maximum length of the magnet. The nearest or larger or main surface of a magnet or magnetic structure or assembly may be separated from the larger or main surface of another ferromagnetic component by a distance about the same as the maximum length of the magnet.

[0400] The nearest or larger or main surface of a magnet or magnetic structure or assembly may be separated from the larger or main surface of another ferromagnetic component by a distance of at least about 0.4 times the maximum length of the magnet. The nearest or larger or main surface of a magnet or magnetic structure or assembly may be separated from the larger or main surface of another ferromagnetic component by a distance of at least about 0.6 times the maximum length of the magnet. The nearest or larger or main surface of a magnet or magnetic structure or assembly may be separated from the larger or main surface of another ferromagnetic component by a distance about the same as the maximum length of the magnet.

[0401] The nearest or relatively large surface of the magnet assembly is separated from the relatively large surface of the other ferromagnetic component in some directions perpendicular to the axis by a distance of at least about 0.4 times the largest dimension of the magnet in the direction parallel to the surface in the surface locality. The nearest or relatively large surface of the magnet assembly is separated from the relatively large surface of the other ferromagnetic component in some directions perpendicular to the axis by a distance of about 0.6 times the largest dimension of the magnet in the direction parallel to the surface in the surface locality. The nearest or relatively large surface of the magnet assembly is separated from the relatively large surface of the other ferromagnetic component in some directions perpendicular to the axis by a distance substantially similar to the largest dimension of the magnet in the direction parallel to the surface in the surface locality.

[0402] In some embodiments, the transducer does not include a magnet or other ferromagnetic component that exerts a force on the magnetic structure or assembly that is greater than 70 times, more preferably greater than 50 times, and most preferably greater than 40 times the force due to gravity acting on the magnet assembly.

[0403] In some embodiments, the transducer includes other ferromagnetic components facing the magnet or magnetic structure or assembly that attract the magnet or magnetic structure or assembly in different or opposite directions, in such embodiments, the net force on the magnet or magnetic structure or assembly due to the other ferromagnetic components is negligible or about zero.

[0404] Vibration Plate Suspension System The diaphragm suspension allows rotation of the diaphragm about the axis of rotation, allowing a range of angular motion of about 10 degrees on either side of the axis, about 15 degrees on either side of the axis, or about 20 degrees on either side of the axis. In this embodiment, the diaphragm suspension includes multiple hinge mounts A107a, A107b. In some embodiments, a single hinge mount may be used.

[0405] The hinge mounts A107a and A107b are located outside the diaphragm-side transduction components. In some embodiments, a pair of hinge mounts can be located on either side of the diaphragm A101's midsagittal plane, which is substantially perpendicular to the rotation axis A103, with each hinge mount A107a and A107b located at a distance of at least 0.2 times the maximum width of the diaphragm A101 from the midsagittal plane. Each hinge mount can be located at a distance of less than approximately 0.47, 0.45, or 0.42 times the maximum width of the diaphragm A101 from the midsagittal plane, which can be particularly important in embodiments using a rigid hinge design approach, because such positioning can position the hinges near the nodal locations for the diaphragm base bending modes, resulting in improvements in the corresponding resonant frequencies.

[0406] Because both the diaphragm A101 and the base structure A102 are relatively stiff and connected to each other via a relatively compliant diaphragm suspension system including two diaphragm suspension bushings A107a and A107b, there can be six fundamental, relatively low-frequency vibration modes of the transducer resulting primarily from the compliance of the diaphragm suspension system. These can include three modes with significant translational components (possibly along three substantially orthogonal axes) and three modes with significant rotational components (possibly about three substantially orthogonal axes). The rotational mode frequencies about a transverse axis A202a / A103, which is substantially orthogonal to the sagittal plane A201 of the diaphragm A101, are the primary excitation modes of the transducer A100 (hereafter referred to as primary modes). The diaphragm motion in the primary modes can be considered equivalent to the piston modes of a conventional linear cone driver. Because the direction of the primary flux in magnet A205 is substantially perpendicular to the direction of the flux generated by coil A106, the principal torque generated on magnet A205 is in the same direction as the primary mode. Audio transducer 100 preferably operates substantially in a single degree of freedom manner, whereby the primary mode is substantially the only source of audible sound (in an electroacoustic configuration).

[0407] Five other modes may also be excited during operation. However, the design of transducer A100 is such that most of these modes do not result in significant net air movement and cause substantially little audible degradation in the quality of the reproduced audio. For example, in this embodiment, the two approximately translational modes involving diaphragm A101 translating along longitudinal axis A211a or transverse axis A202a, and the approximately rotational mode about sagittal axis A201a, which is substantially perpendicular to the coronal plane A211 of diaphragm A101, do not push air enough to cause significant changes in sound pressure, even when they are excited. Moreover, in this embodiment, due to symmetry, these modes may not be strongly excited. A rotational mode about the longitudinal axis A211a (orthogonal to the transverse plane A211 of the diaphragm A101) can generate air displacement, but this is substantially mitigated by a cancellation between positive and negative air pressures generated at the sides of the diaphragm on either side of the sagittal plane A201. In this embodiment, due to symmetry, this mode may not be strongly excited. In some embodiments, excitation of a mode in at least a portion of the diaphragm having a significant translational component in a direction substantially parallel to the sagittal axis of the diaphragm A101 (hereinafter referred to as Mode A) may be minimized or substantially mitigated by the location of the diaphragm suspension mounts A107a, A107b at or near the diaphragm nodal axis A104. In some embodiments, excitation of Mode A may be minimized by locating the diaphragm's primary axis of rotation A103 in a plane A213 that is substantially perpendicular to the coronal plane A211 of the diaphragm A101 and that contains / intersects the nodal axis A104 of the diaphragm A101. In some embodiments, the primary axis of rotation A103 and the diaphragm nodal axis A104 may be substantially coaxial.

[0408] During operation, in a first operating mode, in which the transducer is operating at frequencies significantly below the resonant frequencies of the primary and five other modes, the location of the diaphragm A101 axis of rotation A103 relative to the base structure A102 can be significantly influenced by the diaphragm suspension and by forces exerted on the diaphragm A101 by the translation mechanism. The first operating mode resembles a region of controlled transducer stiffness for all six diaphragm resonant modes, driven primarily by diaphragm suspension compliance. In a second operating mode, in which the transducer is operating at frequencies significantly above the resonant frequencies of the primary and five other suspension compliance modes, the location of the diaphragm A101 axis of rotation relative to the transducer base structure A102 can be primarily defined by the location of the diaphragm nodal axis A104 and less significantly by the diaphragm suspension. The diaphragm nodal axis A104 is defined primarily by the force applied to the diaphragm A101 by the translation mechanism and by the mass distribution / profile of the diaphragm A101 (including the magnet A205). In the second operating mode, the diaphragm nodal axis A104 may be relatively unaffected by the diaphragm suspension. The second operating mode resembles a mass-controlled region of transducer operation with all six diaphragm resonant modes primarily driven by diaphragm suspension compliance.

[0409] The translation mechanism can be configured so that the force applied to the diaphragm A101 during operation is substantially pure torque. This causes the diaphragm nodal axis A104 to be substantially coaxial with the center of mass A204. In this embodiment, the flexible mounts A107a, A107b of the diaphragm suspension are substantially coaxial with the diaphragm center of mass A204. In some embodiments, the overall effect of the diaphragm suspension on the diaphragm A101 is such that the axis of rotation A103 of the diaphragm A101 relative to the transducer base structure A102 is substantially coaxial with, or at least proximate to, the diaphragm center of mass A204 in the first mode of operation.

[0410] In some configurations, the force applied to the diaphragm A101 by the translation mechanism during operation may not be substantially pure torque. In such configurations, the diaphragm nodal axis A104 may not coincide with the diaphragm center of mass A204, and the flexible mounts A107a, A107b of the diaphragm suspension system may be located substantially coaxially with the diaphragm nodal axis A104. In some embodiments, the overall effect of the diaphragm suspension on the diaphragm A101 is such that the axis of rotation A103 of the diaphragm A101 relative to the transducer base structure A102 is substantially coaxial with, or at least proximal to, the diaphragm nodal axis A104 in the first operating mode.

[0411] If the diaphragm nodal axis A104 is not located coaxially with or near the rotation axis A103 in the first operating mode, the sound pressure frequency response of the transducer A100 may have a step at or around the frequency of Mode A because the rotation axis translates from a first location A103 (defined by the diaphragm suspension system) to a second location (defined by the diaphragm nodal axis A104). An associated resonance peak and / or dip may also be present. By configuring the diaphragm A101 and the translation mechanism so that the diaphragm nodal axis A104 is located substantially coaxially with the rotation axis A103 in the first operating mode, performance advantages may be realized. This results in a flatter frequency response and improved sound quality at and around the frequency of the Mode A resonance. Configuring the translation mechanism to provide a substantially pure rotational torque to the diaphragm A101 shifts the nodal axis A104 to the location of the diaphragm center of mass A204. The diaphragm A101 can then be shaped so that the diaphragm center of mass A204 is in the desired location for connecting the diaphragm suspension mounts A107a, A107b. In some embodiments, the diaphragm suspension mounts are connected near one end A101a of the diaphragm body A207 to improve transducer performance. Because most of the mass of the diaphragm A101 is in the magnet A205, a way to achieve a center of mass near the end A101a is by shaping the magnet so that the side closest to the diaphragm's distal tip A101b is truncated relative to the side at the terminal end A101a. The surface of the magnet where the north and south poles reside is preferably concentrically convexly curved around the axis of rotation A103 (at least in the first mode of operation) because this minimizes the required air clearance for the coil.

[0412] Another performance benefit of positioning the center of mass of the diaphragm A204 so that it is substantially coaxial with the axis of rotation A103 in the first operating mode is the minimization of other deleterious vibration modes associated with diaphragm suspension compliance, resulting in a flatter frequency response and improved sound quality.

[0413] The pair of diaphragm suspension mounts A107a, A107b shown in FIGS. 4A-4C can each include a substantially solid body with a central aperture for securely receiving a corresponding pin A108a, A108b therein. In some embodiments, each mount A107a, A107b can include one or more cavities that contain a fluid (e.g., air) or a relatively lower density or stiffness material located therein. The material can be, for example, a foam containing multiple air pockets. In some embodiments, each mount A107a, A107b can be formed from urethane foam. In such a configuration, the maximum range of motion can be increased and / or the fundamental diaphragm resonant frequency can be reduced without excessively reducing translational stiffness. The geometry of each hinge mount A107a, A107b can potentially be made relatively thicker and / or shorter. This may be utilized in very small, sensitive speaker drivers, for example, where the hinge components are very small and / or the less sensitive hinge features may be less prone to internal resonant modes.

[0414] 17A and 17B, in some embodiments, each hinge mount A107a, A107b can be replaced with hinge mount A700. Hinge mount A700 is formed from an anisotropic material, such as an anisotropic foam. The anisotropy of the flexible hinge mount can be such that the mount includes a relatively greater resistance to translational deformation relative to resistance to rotational deformation. In other words, flexible hinge mount A700 includes a greater rotational compliance (particularly about the mount's longitudinal axis A703 or diaphragm's rotation axis A103) relative to translational compliance. This can allow for a relatively low fundamental resonant frequency and translational stiffness, which can help mitigate or reduce material creep over time.

[0415] In some embodiments, the flexible hinge mount may be formed from a foam material. The foam may include multiple cavities A701 extending longitudinally through the mount body A702. In some embodiments, the anisotropic material of the mount A700 may have a relatively high Young's modulus in a direction perpendicular to the coronal plane of the diaphragm A101 and / or in a direction substantially perpendicular to the longitudinal axis A703 of the mount A700, which may provide higher resistance to translational displacement relative to rotational compliance about the longitudinal axis A703. Inaccurate manufacturing (e.g., incorrect diaphragm mass, etc.) is more likely to result in translation in the direction perpendicular to the coronal plane of the diaphragm compared to other non-primary diaphragm resonant modes. Also, better restraint of the diaphragm in this direction may allow for a smaller gap between the magnet and coil windings for improved efficiency.

[0416] The cavity A701, in this embodiment, is substantially annular, such that the compliance of the mount in terms of translation along a first axis A704, which is substantially perpendicular to the longitudinal axis A703 of the mount, is substantially similar to the compliance of the mount in terms of translation along a second axis A705, which is substantially perpendicular to the longitudinal axis A703. Referring to FIGS. 18A and 18B , in some embodiments, the cavity A701 can alternatively be substantially elliptical in cross section, such that the compliance along the first axis A704 is different from the compliance along the second axis A705. In this case, the compliance along axis A704 is higher than the compliance along axis A705. The orientation and shape of the cavity can be varied to achieve a particular compliance profile along each axis A704, A705. The cavity A701 can extend along a substantial portion or the entire length of the body A702.

[0417] In yet another example, mounts A107a and A107b may be replaced by mount A800 of FIGS. 19A-19C. As shown, the mount includes a single longitudinal body A801 ​​extending between opposing annular connection heads A802, A803. The longitudinal body A801 ​​may include one or more external concave surfaces along surfaces A801a, A801b extending along the length of the body A801. The surfaces may be concave in a transverse cross section of the body A801. Surfaces A801a and A801b may be oriented approximately 180 degrees relative to each other in this example. Other orientations are contemplated, and in some embodiments, any number of one or more concave surfaces may be present. The concave surfaces may be angled or curved inward toward a central region or axis of the mount, such that the central region may be relatively thinner than adjacent regions on either side. Heads A802 and A803 can be configured to rigidly couple transducer base structure A102 and diaphragm A101, respectively. In some embodiments, one such mount can be attached at each end of the diaphragm base structure, with the respective axes substantially coaxial with the axes, such that deformation is primarily via torsion during use. Other orientations are also possible.

[0418] In yet another example, mounts A107a and A107b may be replaced by mount A800 of FIGS. 19A-19C. As shown, the mount includes a single longitudinal body A801 ​​extending between opposing annular connection heads A802, A803. The longitudinal body A801 ​​may include one or more external concave surfaces along surfaces A801a, A801b extending along the length of the body A801. The surfaces may be concave in a transverse cross section of the body A801. Surfaces A801a and A801b may be oriented approximately 180 degrees relative to one another in this example. Other orientations are contemplated, and in some embodiments, any number of one or more concave surfaces may be present.

[0419] Mounts A107a, A107b may be replaced with alternative mounts, such as those shown in FIGS. 5A-5C and 6A-6D. FIGS. 5A-5C illustrate an alternative spoke mount A500 having multiple inner spokes A501 extending radially between inner and outer walls A503, A504 to provide additional compliance in the direction of rotation about pin aperture A505 relative to translational compliance along all three orthogonal axes. Two such suspension mounts may be located distally relative to each other along the primary axis of rotation such that they interlock with each other to provide higher compliance in the direction of rotation about pin aperture A505 relative to rotational compliance about the other two orthogonal axes of rotation. For example, mounts A107a, A107b may be located on or near opposite sides of diaphragm A101. All else being equal, in this example, it may be possible to use a harder grade material for mounts A107a, A107b. For example, an elastomer having a Shore A hardness of about 60 may be utilized. The longitudinal cavities A502 formed between radial spokes A501 and between inner wall A503 and outer wall A504 may contain air or, alternatively, may contain a material of lower density or stiffness relative to the spokes A502 and walls A403, A504.

[0420] In some embodiments, audio transducer A100 can include diaphragm suspension mounts as shown in FIGS. 6A-6D. Each mount can be a cross-flexure hinge mount A600 having four spokes or flexures A601a-d radiating from a central axis A603 and providing additional compliance about the central axis in addition to translational compliance along three orthogonal axes. Preferably, pairs of mounts are located substantially distal to each other along the primary axis of rotation A103, such that additional rotational compliance about an axis substantially orthogonal to the central axis can also be achieved. This can also allow a relatively harder grade of material to be used for mounts A107a, A107b. For example, a urethane elastomer having a Shore A hardness of 60 can be utilized. The crossflexure body A601 is connected to a mounting pad A602 on one side via a connector A602a extending from the pad A602.

[0421] Both hinge mounts A500 and A600 can include at least one concave surface that promotes bending of the hinge at or about those surfaces. In foam-type materials, the internal cavities also include concave surfaces that promote this flexible behavior. Preferably, at least one surface is concave about an axis substantially parallel to the axis of rotation of diaphragm A101 to promote bending about the axis of rotation. In some embodiments, there can be a relatively high number of surfaces that are concave about the axis of rotation relative to other orthogonal axes, promoting higher rotational compliance about the axis of rotation and relatively lower compliance in translation along and / or rotation about the other orthogonal axes.

[0422] In some embodiments, hinge mounts A107a and A107b may be replaced by any other diaphragm suspension described herein in connection with other embodiments. Moreover, any of the hinge mounts described in connection with transducer A100 may be used in connection with any other audio transducer embodiment described herein.

[0423] The compliance of the diaphragm suspension system can be customized to the requirements of a particular driver application. For example, a high-frequency driver in a two-way home audio speaker may not require a low first-order mode frequency, and therefore a relatively less compliant diaphragm suspension system may be used, which may provide the advantage that the diaphragm structure is stiffer against displacement of the diaphragm relative to the base due to creep of the diaphragm suspension system material, thereby improving transducer robustness in such applications.

[0424] In some embodiments, each hinge mount of the diaphragm suspension has a sufficiently low Young's modulus such that the fundamental diaphragm resonant frequency occurs at a frequency less than about 100 Hz. In some embodiments, each hinge mount of the diaphragm suspension has a sufficiently low Young's modulus such that the fundamental diaphragm resonant frequency occurs at a frequency less than about 70 Hz. In some embodiments, each hinge mount of the diaphragm suspension has a sufficiently low Young's modulus such that the fundamental diaphragm resonant frequency occurs at a frequency less than about 50 Hz. Such a device may be useful as a bass driver or in personal audio applications, as described in more detail below.

[0425] In some embodiments, the audio transducer may include a translational resonant frequency above about 200 Hz, above about 300 Hz, or above about 400 Hz, which may make the device suitable as a mid-range / high frequency driver or even as a personal audio device.

[0426] In some embodiments, one or more diaphragm suspension components (e.g., respective hinge mounts, etc.) are sufficiently stiff so that diaphragm resonant frequencies associated with translational compliance occur at frequencies greater than about 200 Hz, more preferably greater than about 300 Hz, and most preferably greater than about 400 Hz. Diaphragm resonant frequencies associated with translational compliance can involve significant displacement of the diaphragm in a direction perpendicular to the coronal plane.

[0427] The materials and / or construction of the diaphragm suspension can provide substantially high damping, particularly in tension / compression, to help manage translational and other undesired resonance modes.

[0428] In some embodiments, the diaphragm suspension may be comprised of a substantially rigid hinge construction, as described, for example, in Section 3.2 of WO 2017 / 046716, with the hinge's axis of rotation lying in a predetermined plane that is substantially perpendicular to the coronal plane of the diaphragm and contains the diaphragm's nodal axis A104. More preferably, the axis of rotation is substantially coaxial with the nodal axis A104, and most preferably, the axis of rotation is substantially coaxial with the center of mass. Such a suspension may include at least one hinge mount having a pair of substantially rigid, opposing contact surfaces configured to move relative to each other during operation. One contact surface may be rigidly coupled to or form part of the diaphragm A101, while the other contact surface may be rigidly coupled to or form part of a transducer base structure. A biasing mechanism may bias the contact surfaces toward one another.

[0429] Method for identifying nodal axes and assembling transducers The diaphragm nodal axis A104 is preferably predetermined and the diaphragm suspension system is mounted to the diaphragm A101 accordingly. Referring to FIG. 22A, a method 200 for constructing an audio transducer A100 includes: a) determining the nodal axis of the diaphragm (step 201); b) coupling a transduction mechanism to the diaphragm and transducer base structure (step 202); c) rotatably mounting the diaphragm to the transducer base structure via a diaphragm suspension such that the axis of rotation of the diaphragm relative to the transducer base structure lies in a predetermined plane, the predetermined plane being substantially perpendicular to the coronal plane A211 of the diaphragm A101 and containing the nodal axis A104 of the diaphragm A101 (step 203); It is possible for the

[0430] Steps a) and b) may be interchanged.

[0431] Alternatively, the diaphragm suspension and / or diaphragm A101 are adjusted until the desired behavior / characteristics of the transducer are achieved.

[0432] In this embodiment, the diaphragm nodal axis A104 is predetermined through predetermined computer modeling and simulation. For example, determining the nodal axis A104 can consist of the following steps: generating a computer model of an audio transducer; simulating an operating condition in which the translation mechanism of the model effectively rotates the diaphragm of the model in a substantially unsupported manner; determining an axis of rotation of the model diaphragm from the simulation; Determining the nodal axis of the audio transducer from the axis of rotation of the model diaphragm.

[0433] Alternatively, a method for predetermining nodal axes A104 may include determining the axes using a physical model similar or equivalent to audio transducer A100. The steps of such a method may include: generating a physical model of an audio transducer; operating a translation mechanism of the model to rotate the model diaphragm in an effective substantially unsupported manner; determining an axis of rotation of the model diaphragm relative to the transducer base structure; determining the nodal axis of the audio transducer from the axis of rotation of the model diaphragm; It is possible for the

[0434] As used herein, references to an "effectively substantially unsupported" diaphragm are intended to mean a diaphragm that is significantly unsupported relative to the level of support provided by the associated diaphragm suspension system. This can be a relatively higher level of support in compliance and / or it can be the result of operating the transducer such that the diaphragm is within a mass-controlled region for the six diaphragm resonance modes primarily driven by diaphragm suspension compliance, where it is effectively substantially unsupported relative to the transducer base structure. When an effectively substantially unsupported diaphragm state is achieved through operation, the operating period of excitation is preferably sufficiently short and the frequency is sufficiently high so that the effect of the diaphragm suspension on the nodal axis location is substantially negligible. In this manner, the diaphragm is effectively unsupported for purposes of determining the diaphragm nodal axis location. Additionally or alternatively, a relatively highly compliant diaphragm suspension can be incorporated to reduce the degree of diaphragm support and achieve an effectively substantially unsupported state of the diaphragm.

[0435] The operating period of the test excitation (where the diaphragm is effectively substantially unsupported) is preferably sufficiently long and / or the frequency of operation is sufficiently low so that both the diaphragm and the transducer base structure remain substantially rigid, or at least so that any deformation of either has a substantially negligible effect on the determined nodal axis location.

[0436] Preferably, determining the axis of rotation of the model includes measuring the axis using one or more sensors or measurement devices (e.g., an accelerometer, a laser Doppler vibrometer (LDV), or a proximity sensor, etc.).

[0437] As noted, in an alternative embodiment, audio transducer A100 is constructed using techniques that adjust the characteristics of the transducer to achieve desired operating characteristics. Referring to FIG. 22B, method 210 includes: a) i. by coupling a translation mechanism to the diaphragm A101 and the transducer base structure A102; and ii. by rotatably mounting the diaphragm A101 to the transducer base structure A102 via a diaphragm suspension system; Partially assembling an audio transducer (step 211); b) operating the translation mechanism to rotate the diaphragm A101 of the partially assembled audio transducer (step 212); c) analyzing one or more operational characteristics of the partially assembled audio transducer (step 213); d) adjusting one or more physical attributes of the partially assembled audio transducer to optimize one or more operating characteristics (step 214); e) repeating steps b) through d) as necessary until one or more desired criteria of one or more operational characteristics are achieved (step 215); It is possible to include:

[0438] The desired criteria are preferably predetermined. Step b) can include operating the translation mechanism to rotate the diaphragm within the mass control region of the transducer for six diaphragm resonance modes driven primarily by diaphragm suspension compliance.

[0439] Preferably, the one or more operational characteristics include any one or more of the frequency response of the transducer at least within the frequency range of the intended operation. Preferably, the criteria include a zero-resonance frequency response.

[0440] In some embodiments, step c) comprises analyzing the frequency response of the transducer and determining whether values ​​of one or more parameters indicative of a step-like change in the frequency response are greater than a predetermined threshold. Preferably, the criteria of step e) comprise desired values ​​of one or more of the parameters. For example, the parameters may be the height and / or slope of the step, and the criteria may comprise a desired maximum height and / or slope value.

[0441] In some embodiments, step c) comprises analysing the frequency response of the transducer and determining whether a peak value of the frequency response is greater than a predetermined threshold. Preferably, the criteria for step e) comprises a desired maximum value of the peak frequency response.

[0442] The above-mentioned parameter values ​​related to the frequency response can be measured or estimated.

[0443] Preferably, the one or more physical attributes include any combination of one or more of: location of the diaphragm suspension system relative to the diaphragm; location of the axis of rotation of the diaphragm relative to the transducer base structure; mass profile of the transducer base structure; mass profile of the diaphragm; one or more dimensions of the diaphragm; shape profile of the diaphragm; shape profile of the base structure; shape profile of the diaphragm suspension system; stiffness profile of the diaphragm suspension system; force generation profile of the conversion mechanism.

[0444] 22C, in yet another method, audio transducer A100 can be constructed based on the diaphragm's center of mass axis A204. For example, method 220 may include: a) determining the center of mass axis A204 of the diaphragm A101 (step 221); b) coupling a translation mechanism to the diaphragm A101 and the transducer base structure A102 (step 222); c) rotatably mounting the diaphragm A101 to the transducer base structure A102 via the diaphragm suspension system such that the axis of rotation A103 of the diaphragm A101 relative to the transducer base structure A102 lies in a predetermined plane, the predetermined plane being substantially perpendicular to the coronal plane A211 of the diaphragm A101 and containing the center of mass axis A204 of the diaphragm A101 (step 223); It is possible to include:

[0445] The axis of rotation A103 is preferably substantially coaxial with the center of mass axis A204.

[0446] Decoupling Mounting System Referring to FIGS. 1F-1I and 3G, in some configurations, audio transducer A100 may be housed within a speaker enclosure or housing A301. To minimize unwanted vibration transmission between speaker housing A301 / A301 and transducer A100, transducer A100 is preferably coupled to the housing via a flexible decoupling mounting system. In some embodiments, this system can be similar to the decoupling mounting system described in section 4 of WO 2017 / 046716, for example, in connection with embodiment A. The decoupling mounting system of this embodiment includes a pair of flexible transducer node axis mounts A305a, A305b extending laterally from opposite sides of transducer base structure A102, substantially coaxial with the transducer node axis A105. As explained in Section 4.2.1 of the detailed description of WO2017 / 046716 (e.g., WO2017 / 046716 is incorporated herein by reference), the transducer nodal axis A105 (which is different from the diaphragm nodal axis A104 described above) is a predetermined location about which the transducer base structure rotates when it is effectively substantially unsupported during operation (referred to herein as the unsupported active state). In summary, the transducer nodal axis A105 is the axis about which the transducer base structure rotates due to reaction and / or resonance forces exhibited during diaphragm oscillation. The location is determined when the transducer assembly is operated in a virtually unsupported state and at a frequency substantially lower than the frequency at which unwanted diaphragm (flexural type) and transducer base structure (flexural type) resonance occurs. This method of identifying locations is described in WO2017 / 046716, which is incorporated herein by reference.

[0447] In some embodiments, the transducer nodal axis A105 can be determined when the transducer assembly is operated in a virtually unsupported state, and when it is operated at a frequency substantially lower than the frequency at which unwanted diaphragm (flexural type) and transducer base structure (flexural type) resonance occurs, and when it is operated at a frequency substantially higher than the frequency of the resonant modes associated with the diaphragm suspension compliance (the six modes described above).

[0448] In some embodiments, the transducer nodal axis A105 can be determined when the transducer assembly is operated in a virtually unsupported state and at a frequency substantially lower than the frequency at which unwanted diaphragm (flexural type) and transducer base structure (flexural type) resonance occurs, and at a frequency higher than the frequency of the primary diaphragm resonance mode.

[0449] The decoupling mounting system includes node axis mounts A305a, A305b, which extend laterally from opposite sides of the transducer base structure A102 substantially coaxially with the transducer node axis A105. The node axis mounts are coupled around node axis pins A111a, A111b, which also extend laterally from opposite sides of the transducer base structure A102 substantially coaxially with the node axis A105. The mounts A305a, A305b are fixedly received within corresponding recesses or cavities within the enclosure part A301. The mounts can have a profile similar to that of the diaphragm mounts A107a, A107b or the diaphragm mounts shown in Figures 5A-5C and 6A-6D, for example.

[0450] The decoupling mounting system further includes one or more decoupling pads A306a, A306b located on one or preferably both major surfaces of the transducer base structure A102. The pads A306a, A306b provide an interface between an associated base structure surface and a corresponding interior wall / surface of the enclosure, helping to decouple the components. In this example, one pad A306a is located on each major surface (upper and lower) of the base structure. The decoupling pads are preferably located in regions of the transducer base structure distal to the transducer nodal axis A105. For example, the decoupling pads are located at or adjacent to the edge of the base structure adjacent to the diaphragm A101. Each pad A306a, A306b is preferably longitudinal in shape, extending longitudinally along a transverse edge of the base structure A102. As shown in FIG. 3G, each pad A306a, A306b includes a pyramidal-shaped body having a tapered width along its depth. Preferably, the apex of the pyramid is coupled to the housing, although this orientation may be reversed in alternative embodiments. In alternative embodiments, the decoupling mounting system may include multiple pads distributed around one or more of the major surfaces of the transducer base structure A102 and / or on the sides of the base structure from which the decoupling pins extend, with the understanding that the present invention is not intended to be limited to this example configuration, as will be apparent to those skilled in the art. Such mounts are referred to herein as "distal mounts."

[0451] The nodal axis mounts A305a, A305b and distal mounts A306a, A306b are sufficiently compliant in terms of relative movement between the two components to which they are respectively attached. For example, the nodal axis mounts and distal mounts can be sufficiently flexible to allow relative movement between the two components to which they are attached. They can include flexible or elastic members or materials to achieve compliance. The mounts preferably include a low Young's modulus relative to at least one, but preferably both, components to which they are attached (e.g., relative to the transducer base structure and housing of an audio device). The mounts are also preferably well damped. For example, the nodal axis mounts A305a, A305b can be made from an elastomer or soft plastic material (e.g., silicone rubber, etc.), and the pads A306a, A306b can be made from a substantially flexible material (e.g., silicone rubber, etc.).

[0452] The nodal axis and distal mount may be made from materials having Young's modulus values ​​of about 0.2 MPa to 20 MPa, preferably, for example, less than 1 GPa. These values ​​are merely exemplary and are not intended to be limiting. It is understood that compliance also depends, for example, on the geometry of the material, the frequency range of operation of the driver, and the mass of the diaphragm structure, so materials having other Young's modulus values ​​may also be used.

[0453] The decoupling system in the nodal axis mounts A305a, A305b has less compliance (i.e., is stiffer or forms a stiffer connection between the associated parts) than the decoupling system in the distal mounts A306a, A306b. This can be achieved through the use of different materials and / or, in this embodiment, by changing the geometry (e.g., shape, form, and / or profile, etc.) of the nodal axis mounts A305a, A305b relative to the distal mounts A306a, A306b. This difference in geometry means that the nodal axis mounts A305a, A305b include a larger contact surface area with the base structure and housing relative to the distal mounts A306a, A306b, thereby reducing the compliance of the connection between these parts.

[0454] In practice, a transducer mounted in a high-quality decoupling mounting system can have a transducer nodal axis location that moves during operation. In the relatively low frequency range (relative to the FRO), the movement of the transducer base structure (and nodal axis location, if present) is primarily defined by the mechanical constraints of the transducer decoupling mounting system, by the location and direction of the force exerted by the diaphragm on the transducer base structure, and by the mass distribution of the transducer base structure assembly (referred to herein as the "first operating state"). In general, the movement of the transducer base structure will be different; if present, the nodal axis will be shifted compared to the movement in a virtual, unsupported, active state of the transducer, and can shift with frequency. At frequencies above this lower range, the transducer base structure movement (and nodal axis location, if any) will be primarily defined by the location and direction of forces applied to the transducer base structure (e.g., reaction forces from diaphragm oscillation, resonant forces, and forces applied to the transduction mechanism, etc.) and by the mass distribution of the base structure assembly (referred to herein as the "second operating state"), which is typically the same as the nodal axis location in the hypothetical unsupported active state at a particular operating frequency. As explained above, some embodiments of the present invention include a compliant hinge system that allows the effective diaphragm hinging axis to shift over the operating bandwidth, and therefore allows the direction of the force applied to the transducer base structure (and, implicitly, the transducer nodal axis as well) to shift with (steady-state) frequency over the operating bandwidth.Preferably, the transducer nodal axis is determined when the transducer assembly is operated virtually unsupported (with respect to a housing, enclosure, or other support), at frequencies substantially below those at which unwanted diaphragm flexure-type and transducer base structure flexure-type resonances occur, and at frequencies substantially above those of the resonant modes associated with the diaphragm suspension compliance (the six modes described above). The decoupling mounting systems described herein resist or at least significantly reduce such changes in movement, including aspects of shifts in the transducer nodal axis location. The decoupling mounting systems are designed so that within the frequency range of operation, there is very minimal or no movement of the transducer nodal axis caused by the decoupling mounting system, and translational movement at the less compliant decoupling locations is minimized or prevented.

[0455] 1G-1I show finite element analysis results of a simulated model of audio transducer A100 in an active state, effectively substantially unsupported (relative to a housing, enclosure, or other support onto which the transducer may be coupled in situ) to facilitate location and pre-determination of the transducer nodal axis A105 for positioning nodal axis mounts A305a, A305b accordingly. The primary mode rotation about an axis substantially parallel to the transducer's transverse axis A202a is shown in these figures. It is noted that in this case, the diaphragm suspension is designed to avoid a shift in the diaphragm's axis of rotation compared to the predetermined (diaphragm) nodal axis A104 of the diaphragm A101; thus, this is the special case where the primary resonant mode of the diaphragm has the same diaphragm axis location as the predetermined (diaphragm) nodal axis of diaphragm rotation A104. Thus, in this analysis, the location of the transducer nodal axis is the same when the transducer assembly is operated in a virtually unsupported state (with respect to a housing, enclosure, or other support onto which the transducer may be coupled in situ), and when it is operated at frequencies lower than those at which unwanted diaphragm bending-type and transducer base structure bending-type resonances occur, and when it is operated at frequencies substantially higher than the frequencies of the resonant modes associated with the diaphragm suspension compliance (the six modes described above).

[0456] Two nodal axes are evident (diaphragm nodal axis A104 and transducer nodal axis A105). The size and direction of each arrow in the finite element analysis plot indicates the relative magnitude and direction of displacement of each region on the transducer. The diaphragm A101 in FIG. 1F can be seen to be rotating in the opposite (clockwise) direction about the diaphragm nodal axis A104 relative to the base assembly (which is rotating counterclockwise about the transducer nodal axis A105).

[0457] The distance between the transducer nodal axis A105 and the diaphragm nodal axis A104 is preferably relatively small. This is advantageous because it means that the stiffer nodal axis mounts A305a, A305b are relatively closer to the diaphragm and to the diaphragm's rotational axis A103 relative to the base structure A102, and therefore any displacement (especially rotational displacement) of the transducer base structure A102 relative to the housing that may occur in an impact scenario results in a smaller displacement of the diaphragm relative to the housing. This, in turn, results in a reduced likelihood of damage to the diaphragm, all else being equal.

[0458] Loudspeaker Embodiments 3A-3H show a transducer A100 mounted in a speaker device A300 that may be used for home audio applications, such as a midrange / treble speaker. The speaker A300 includes an enclosure A301, an enclosure lid A302, the transducer A100, a protective surround A303 around the outer periphery of the diaphragm A101, an outer shielding mesh A308, an inner shielding mesh A309, and a driver decoupling system consisting of two decoupling bushings A305a, A305b and two decoupling pyramids A306a, A306b.

[0459] Transducer A100 can be configured for many different applications, for example, in alternative embodiments, as a full-range headphone driver. Transducer A100 can be made larger for use as a mid-range driver, bass-mid driver, full-range driver, or subwoofer, or smaller for use in personal audio applications such as headphones, mobile phones, earpieces, or hearing aids. Transducer A100 can also be used as a mechanical vibration transducer or can have a dual purpose as both a sound transducer and a mechanical vibration transducer. Transducer A100 can also be used as a microphone.

[0460] Protective Surround In this embodiment, the speaker A300 further includes a protective surround A303, which is configured to provide impact protection for the transducer A100 while helping to prevent air from passing around the periphery of the diaphragm. The protective surround A303 may be in-molded into the enclosure A301 / A302 from a compliant material (e.g., an elastomer or plastic material such as silicone rubber or Sorbothane™) or may be coupled as a separate component. Parts of the protective surround A303 that may contact more delicate areas of the diaphragm A101 preferably have small, thin flaps A303a and A303b molded into it. For example, in a potential use situation in which the speaker A300 is dropped, the surround A303 is configured to provide protection via the thin flaps A303, which flex and slide over the diaphragm A101. To additionally help prevent diaphragm damage, a low-friction coating (e.g., PTFE or Teflon) is preferably applied, in-molded, or otherwise attached to areas of the protective surround A303 that may contact the diaphragm A101 during a drop. The protective surround A303 can have other flexible geometries molded, cut, or fabricated into it, rather than a layer of flaps A303 extending around all three sides of the diaphragm, as shown in FIG. 3H . Multiple small flaps or small hairs can be present. The feature of having many small flaps oriented in the plane of the diaphragm A101 helps restrict the flow of air from areas of positive sound pressure generated on one side of the diaphragm A101 to areas of negative sound pressure generated on the other side during operation. The protective surround A303 can alternatively be made from a compliant fabric or material, such as velvet, velour, or silicone.The protective surround A303 can also provide anti-static protection, for example by using an anti-static spray, to help prevent dust from being attracted into the air gap A304.

[0461] Magnetic Shielding In this embodiment, the speaker A300 further includes magnetic shielding parts A308, A309 made of a ferromagnetic material, such as steel mesh. The magnetic shielding parts A308, A309 are used to help prevent the flux field of electromagnetic mechanisms from extending beyond the exterior surface of the speaker A300 and to reduce magnetic interaction with foreign objects outside the speaker A300. Without the shielding, the diaphragm A101 could be displaced due to magnetic interaction with foreign objects (e.g., other magnets or ferromagnetic materials), potentially causing damage. Thus, the speaker A300 includes an outer shielding mesh A308, which includes a panel A308a approximately equal in distance to the magnet A205 as the inner shielding mesh A309. The thickness and density of each shield A308, A309 are similar to the other to maintain equal and opposite magnetic attraction on both sides of the diaphragm A101. In some embodiments, the thickness of different parts of the shielding can vary, and the distance from the transducer can also vary, but the overall effect is that the net force on the diaphragm (and preferably the transducer) is zero or at least close to zero. In some embodiments, additional shielding and / or permanent magnets and / or other devices can be incorporated to balance the forces on the diaphragm. Because these forces on the magnets are approximately equal and opposite, the net force on the magnets can be approximately zero. Similarly, the magnetic shielding panels A308b and A308c also attract the magnets from approximately opposite directions, thus providing approximately zero net force on the magnet A205 and diaphragm A101 in the relevant direction. With an approximately zero net force on the magnet A205, the force transmitted through the diaphragm suspension mounts A107a, A107b can be minimized, which can reduce the tendency of the soft mounts A107a, A107b to creep in displacement over time under excessive stress.In this embodiment, there is no shielding on the sides of the enclosure, but this may not be necessary due to the large distance between magnet A205 and these outer surfaces of speaker A300.

[0462] In a scenario where a magnetic foreign object touches the outer surface of speaker A300, preferably the shielding A308 / A309 is sufficient so that the magnetic flux from magnet A205 is contained within speaker A300, and the attractive force from the foreign object to magnet A205 is negligible or at least greatly reduced.

[0463] Additionally or alternatively, the magnetic shielding may be rigidly attached to the base structure assembly A102. In some embodiments, the ferromagnetic materials are preferably located so that they are not too close to the diaphragm magnets or coils and / or are not too large and / or so that they do not carry too much magnetic flux; otherwise, the diaphragm may exist in an unstable equilibrium that may become upset if the diaphragm suspension material were to distort due to creep and / or elevated temperature and / or if manufacturing tolerances are poor.

[0464] In some embodiments, such as in the case of a tweeter, magnetic shielding can provide a secondary benefit as a pole piece, helping to direct either the magnetic flux of magnet A205 or the magnetic flux induced by conductive coil A106 in a direction that improves the overall efficiency of transducer A100.

[0465] Preferably, the shielding is not in close contact with or rigidly connected to the coil. Also, the face or side of coil A106 distal from magnet A205 may preferably be free of any strongly ferromagnetic components in close contact with or rigidly connected to it. Preferably, there is a gap of at least 1 mm between the coil and the strongly ferromagnetic components, more preferably a gap of at least 2 mm, and most preferably a gap of at least 4 mm.

[0466] The net attractive force of all magnetic shielding A308 / A309 on the device (and including the net attractive or repulsive force of any other magnets (e.g., in other transducers A100) acting on magnet A205) is preferably about zero, so as not to overstress the diaphragm suspension system (which could displace the diaphragm A101 and limit transducer performance). The net force on the entire transducer in the non-operating state can be about zero, or alternatively, comparable to or less than gravity, to avoid long-term loading of the driver suspension and possible creep of compliant components (e.g., mounts A107a, A107b, etc.).

[0467] A perforated mesh is used as magnetic shielding for device A300 because air from the front face of the diaphragm must pass through part of shielding panel A308a and also through part of inner shielding panel A309. Alternatively, portions of the shielding that do not require air to pass through (e.g., portions not adjacent to the area of ​​sound pressure generated by the diaphragm during operation) can be made solid, which would then provide more effective shielding of magnetic flux.

[0468] Free periphery The diaphragm A101 includes a periphery that has no physical connection to surrounding structures, such as a protective surround A303. The phrase "no physical connection" as used in this context is intended to mean that there is no direct or indirect physical connection between the associated free region of the diaphragm periphery and the surrounding structure. For example, the free or unconnected regions are preferably not connected to the surrounding structure, either directly or through an intermediate solid component (e.g., a solid surround, solid suspension, or solid sealing element), and are separated from the structure over which they are suspended or would normally be suspended by a gap. The gap is preferably a fluid gap, such as a gas gap or liquid gap.

[0469] Moreover, the term "surrounding structure" in this context is also intended to cover any surrounding structure that houses at least a substantial portion of the diaphragm structure therebetween or within it. For example, a baffle that can partially or entirely surround the diaphragm structure, or even a wall that extends from another part of the electroacoustic transducer and surrounds at least a portion of the diaphragm, can constitute a surrounding structure in this context. Thus, the phrase "no physical connection" can in some cases be interpreted as lacking a physical association with another surrounding solid part. The transducer base structure can be considered such a solid surrounding part. For example, in a rotational action embodiment of the present invention, parts in the base region of the diaphragm structure can be considered to be physically connected to and suspended from the transducer base structure by associated hinge assemblies. However, the remainder of the diaphragm periphery can be free of connection, and thus the diaphragm includes at least a partial free periphery.

[0470] The phrase "at least partially free of physical connection" (or other similar phrases such as "at least partially free perimeter", or sometimes abbreviated to "free perimeter") as used herein in relation to a perimeter is intended to mean a perimeter that is either: The entire perimeter has no physical connection or Otherwise, where the periphery is physically connected to the surrounding structure / housing, at least one or more peripheral regions are devoid of physical connection, such that these regions constitute a discontinuity in the connection around the periphery between the periphery and the surrounding structure.

[0471] For any electroacoustic transducer embodiment described herein, the diaphragm periphery may be at least partially and substantially free of physical connections. For example, the substantially free periphery can include one or more free peripheral regions, each comprising approximately at least 20 percent of the periphery's length or two-dimensional circumference, or more preferably, approximately at least 30 percent of the periphery's length or two-dimensional circumference. More preferably, the diaphragm is substantially free of physical connections, for example, at least 50 percent of the periphery's length or two-dimensional circumference is free of physical connections, or more preferably, at least 80 percent of the periphery's length or two-dimensional circumference is free of physical connections. Most preferably, the diaphragm is approximately completely free of physical connections.

[0472] Preferably, the width of the air gap defined by the distance between the outer periphery of the diaphragm body of each transducer and the housing / surrounding structure is less than 1 / 10, more preferably less than 1 / 20, and even more preferably less than 1 / 40 of the diaphragm body length. For example, the width of each air gap defined by the distance between the outer periphery of the diaphragm body and the surround is less than 1 mm, or more preferably less than 0.8 mm, or even more preferably less than 0.5 mm. These values ​​are exemplary, and other values ​​outside this range may also be appropriate. The surrounding structure fits substantially snugly around the periphery of the diaphragm (but remains physically separated) throughout substantially the entire range of diaphragm motion during operation, ensuring that the surrounding structure is effectively sealed. The combination of the snug-fitting surround and the use of a housing and / or baffle to effectively surround the transducer separates the air adjacent to the diaphragm's primary radiating surface from the air adjacent to the diaphragm's opposite primary radiating surface, creating a positive air pressure, given a particular orientation of rotation.

[0473] A transducer with a substantially free perimeter means that the diaphragm can occupy nearly the entire thickness of the device, which increases the surface area of ​​the major faces and optimizes performance. In rotary action transducers, a substantially free diaphragm perimeter design as described above also allows for increased diaphragm excursion, further improving device performance, while reducing fundamental diaphragm resonances and mitigating unwanted diaphragm breakup resonances at higher frequencies.

[0474] 2. Second Audio Transducer Embodiment 7A-7I, a second preferred audio transducer embodiment B100 is shown comprising a rigid diaphragm B101 mounted to a rigid base structure assembly B102 via a compliant diaphragm suspension consisting of two diaphragm suspension flexure mounts B107a, B107b made from a flexible, and preferably resilient, material. The mounts may also be made from a substantially flexible material, such as a flexible urethane elastomer.

[0475] Audio transducer B100 is similar to transducer A100. For the sake of brevity, similar or identical features and components will not be described in detail. In particular, diaphragm B101 is similar to diaphragm A101 in that it comprises a substantially rigid body B207 reinforced by inner and outer stiffeners B209a-g and B206, respectively. The form of outer stiffener B206 in this embodiment differs from that of diaphragm A101, but its purpose and function are similar. Similarly, transducer base structure B102 comprises a low-stiffness geometry consistent with base structure A102.

[0476] The diaphragm suspension flexibly and rotatably couples the diaphragm B101 to the transducer base structure B102 so that the diaphragm can rotatably vibrate about an axis of rotation B103. The diaphragm suspension system is configured so that the axis of rotation B103 is substantially coaxial with the diaphragm nodal axis B104, and most preferably coaxial with the diaphragm's center of mass axis B204 as described in connection with audio transducer A100. The transduction mechanism is an electromagnetic mechanism and includes a conductive coil B106 and an associated magnet. In this embodiment, the conductive coil B106 is rigidly coupled to the diaphragm B101, and the magnet forms part of the transducer base structure B102. This is advantageous in that the diaphragm is non-magnetic and therefore not attracted to foreign ferromagnetic bodies, reducing the need for magnetic shielding and minimizing the risk of damage to the diaphragm B101.

[0477] During operation, the translation mechanism exerts a force on the diaphragm B101. Examples of such force vectors B114 and B115 are shown in FIG. 7E, where vector B114 is exerted by the long side B106a of the coil and vector B115 is exerted by the long side B106b of the coil. A vector force diagram for this scenario is shown in FIG. 10, showing the resulting vector B126, which is the sum of vectors B114 and B115. The resulting vector B126 is substantially perpendicular to the position of the diaphragm nodal axis B104, with a distance B117 separating the two. This vector can contribute to the excitation of undesired modes of vibration, such as a translational mode perpendicular to the coronal plane of the diaphragm B211. It is preferable to configure the mass and geometry of the components within the diaphragm structure so that the force vectors on the long sides B106a and B106b of each coil act in significantly opposite directions so that the resulting vector is minimized.

[0478] diaphragm suspension The diaphragm suspension includes a pair of diaphragm suspension flexure mounts B107a, B107b extending laterally from opposite sides of the diaphragm B101. A central opening B220a, B220b of each mount B107a, B107b is configured to fixedly couple around a respective suspension pin B108a, B108b that also extends laterally from the associated side of the diaphragm. The suspension pin B108a, B108b extends substantially coaxially with the diaphragm nodal axis B104 and the diaphragm center of mass axis B204. Each mount B107a, B107b may be connected to its respective pin via any suitable mechanism, such as via an adhesive, e.g., epoxy, or via an interference fit. Each diaphragm suspension flexure mount B107a, B107b is comprised of a plurality of substantially thin, flat elements or "spokes" B215a-d, B217a-d spaced radially apart and extending from a central pin opening B220a, B220b. The spokes B215a-d, B217a-d may be substantially uniformly spaced about the central opening / axis. In some embodiments, each mount may comprise a single spoke. At one end of each spoke B215a-d, B217a-d, distal from the central pin opening B220a, B220b is a flexure head B216a-d, B218a-d. Each flexure head B216a-d, B218a-d is configured to couple onto a corresponding formation B224a-d within an internal recess of a corresponding mounting block B109a, B109b of the base structure B102. During assembly, the spokes of each mount may be pre-stretched to allow the respective flexure heads B216a-d, B218a-d to bond onto a formation to securely hold the flexure mounts B107a, B107b within their respective mounting blocks B109a, B109b. During operation, the four spokes B215a-d, B217a-d flex in tension and bending to allow a sufficiently low frequency for the fundamental rotational mode of operation.

[0479] The diaphragm suspension of this embodiment may be replaced with any other diaphragm suspension described herein or may be modified in accordance with any other diaphragm suspension modification or variation described herein.

[0480] Stopper 7G and 7I, the audio transducer B100 further includes stops B223a, B223b to help prevent excessive movement of the diaphragm B101 relative to the base structure B102. Each diaphragm suspension mounting block B109a, B109b has an inner periphery configured to limit translational and rotational movement of the respective mount B107a, B107b. As shown in FIG. 7I, the outermost opening of each mounting block B109a, B109b includes an inner periphery that forms an abutment surface for a respective pin B108a, B108b to abut against the diaphragm B101 if it translates or otherwise moves significantly relative to the transducer base structure. Additionally, as shown in FIG. 7G, the inner periphery of each mounting block B109a, B109b includes stop surfaces B225a, B225b to limit the movement of the flexure plate accordingly. This can help prevent damage to the relatively fragile diaphragm if dropped, for example. The stop surfaces B225a, B225b may be contoured to gently bring the faces of the respective flexure mounts B115a-d, B117a-d into contact, thereby avoiding or at least minimizing the generation of undesirable noise that might otherwise result.

[0481] diaphragm Referring to FIG. 9C, the diaphragm body B207 is shaped to have a thickness that varies along the length of the body. Similar to diaphragm A101, diaphragm B101 also has a first region of relatively greater thickness at one end of the diaphragm (near the base B210) and a second region of relatively less thickness at the other end of the diaphragm (distal from the base B210). In the second region, the diaphragm body B207 tapers at an angle B203, which may be approximately 15 degrees, between the diaphragm's major surfaces B212 and at the diaphragm's tip, so that the thickness tapers along the length in this region. At the intersection between the first and second regions, i.e., approximately midway between the diaphragm's tip and the diaphragm's base region B210, this angle changes, and the major surfaces become substantially parallel so that the thickness remains substantially constant. In the first region, the angle may taper so that the diaphragm reduces in thickness toward the base end. The taper angle of the first region may be smaller than that of the second region.

[0482] The central region where the first and second regions intersect may be located approximately 15-50% of the longitudinal length between the base end and the distal end of the diaphragm, and may be located approximately 20% of the longitudinal length between the base end and the distal end of the diaphragm.

[0483] In this embodiment, the absolute value of the angle of the radiating surface of the diaphragm relative to the coronal plane of the diaphragm between the central region and the proximal end is less than the absolute value of the angle of the radiating surface between the central region and the distal end.

[0484] As with the first embodiment, the profile of each major surface of the diaphragm in this embodiment is substantially convex along the length of the diaphragm and / or along a sagittal cross section of the diaphragm.

[0485] The diaphragm B101 includes a diaphragm base structure B213a, B213b rigidly coupled to the diaphragm body B207. The base structure B213a, B213b may include a pair of substantially flat plates B213a and B213b rigidly coupled to normal stress stiffeners on the major surfaces B212a, B212b of the diaphragm B101. Each plate is sufficiently straight and / or sufficiently supported and / or of a thickness that minimizes bending deformation. Each plate B213a, B213b is formed from a rigid material having a Young's modulus of at least approximately 8 GPa, or at least approximately 20 GPa. The diaphragm base structure may structurally act as a rigid shaft.

[0486] In some embodiments, the diaphragm base structure may be rigidly bonded to the diaphragm body B207 only through components having at least a moderately high Young's modulus, preferably greater than approximately 8 GPa, and most preferably greater than approximately 20 GPa. Adhesives may be used to bond the components together.

[0487] The diaphragm base structures B213a, B213b may be located at or proximate to the axis of rotation B103. The diaphragm base structures B213a, B213b may comprise the majority of the mass of the diaphragm B101. In this embodiment, the diaphragm base structures B213a, B213b may comprise the diaphragm body B207 or may rigidly connect the diaphragm body B207 to the diaphragm suspension. The diaphragm B101 is directly and rigidly connected to the diaphragm suspension via the diaphragm base structures B213a, B213b.

[0488] The diaphragm base structure comprises the diaphragm-side transduction component B106 of the translation mechanism. In this embodiment, the diaphragm base structures B213a, B213b rigidly connect the diaphragm body B207 to the diaphragm-side transduction component B106 of the translation mechanism.

[0489] The diaphragm of this embodiment may be replaced with any other diaphragm described herein or may be modified in accordance with any other diaphragm modification or variation described herein.

[0490] Conversion mechanism In this embodiment, the electromagnetic mechanism includes a magnet structure that is part of the transducer base structure B102 and a conductive coil B106 that is rigidly coupled around the diaphragm base structures B213a, B213b. The magnet structure is rigidly coupled to the transducer base structure. As shown in FIG. 7J, the magnet structure includes a permanent magnet B205, an inner pole piece B113, and outer pole pieces B112a, B112b. The inner pole piece B113 is coupled between the permanent magnet B205, and the outer pole pieces B112a, B112b are coupled to the outside of the permanent magnet B205. In this manner, at least one pair of opposing magnetic poles extends substantially continuously along the length of the magnet. In this embodiment, there are two pairs of opposing magnetic poles on each side of the permanent magnet. In some embodiments, the magnet may consist of only a single pair of magnetic poles. The magnetic poles are positioned on either side of the axis of rotation B103. A magnetic flux is generated between the inner pole piece B113 and each of the outer pole pieces B112a, B112b. The conductive coil B106 is positioned against the edge of the diaphragm body B207 and is configured such that, at its original location, its first long side B106a is located within the magnetic flux between the inner pole piece B113 and the first outer pole piece B112a, and its second long side B106b is located within the magnetic flux between the inner pole piece B113 and the second outer pole piece B112b. Coil reinforcements B214 may be provided. Suspension pins B108a, b extend laterally from either short side of the conductive coil B106.

[0491] In this embodiment, the coil B106 is the diaphragm-side transduction component, similar to the first embodiment, and this component may preferably extend along or substantially proximate to the axis of rotation B103. For example, the coil B106 may overlap the diaphragm along the axis of rotation. The coil B106 also extends substantially parallel to the axis of rotation B103. The coil also overlaps the diaphragm along the center of mass B204 of the diaphragm structure (including the coil B106 and the diaphragm B101).

[0492] Audio transducer B100 may be housed in a speaker enclosure similar to that of speaker A300 via a decoupling mounting system similar to that described in connection with the first embodiment. Furthermore, the diaphragm suspension system of transducer B100 may be utilized in transducer A100, and vice versa.

[0493] The conversion mechanism of this embodiment may be replaced by any other conversion mechanism described herein, or may be modified according to modifications or variations of any other conversion mechanism described herein.

[0494] 3. Third Audio Transducer Embodiment 12A-12P, there is shown a third audio transducer embodiment D100 comprising a substantially rigid diaphragm structure D200 mounted to a substantially rigid base structure D102 via a compliant diaphragm suspension. The diaphragm suspension is configured to rotatably mount the diaphragm structure D200 relative to the base structure D102 such that the diaphragm structure D200 rotatably vibrates about an axis of rotation D103 during operation.

[0495] In this embodiment, the diaphragm suspension is configured such that the rotation axis D103 is substantially coaxial with the nodal axis D104 of the diaphragm structure D200. The nodal axis may be predetermined or may be determined during assembly of the transducer D100, for example, according to the method described in connection with the first embodiment. In this example, the nodal axis and the rotation axis D103 are substantially coaxial with the center of mass axis of the diaphragm structure D200. In some embodiments, the diaphragm suspension may be configured such that the rotation axis D103 is substantially perpendicular to the coronal plane of at least one diaphragm of the structure D200 and may lie in a plane that includes the nodal axis of the diaphragm structure D200, for example, as described in connection with the first embodiment. In this embodiment, the transducer D100 comprises an electromagnetic conversion mechanism comprising a coil assembly including a coil D109 supported by an inner former D111 and outer formers D112a and D112b, and a magnet assembly including an inner magnet D110, an outer magnet, and pole pieces D221-D224. The coil assembly is rigidly coupled to and forms a portion of the diaphragm structure D200, and the magnet assembly is coupled to and forms a portion of the transducer base structure D102. In some embodiments, the magnet assembly may be coupled to and forms a portion of the diaphragm structure D200, and the coil assembly may be coupled to and forms a portion of the transducer base structure D102. In some embodiments, the transduction mechanism may comprise a piezoelectric mechanism, an electrostatic mechanism, or other suitable mechanism known in the electrical arts.

[0496] diaphragm structure 12L-12P, audio transducer D100 of this embodiment comprises a multiple diaphragm construction. Diaphragm structure D200 comprises a first diaphragm D201 and a second diaphragm D202 extending from a common diaphragm base structure D203. The first diaphragm D201 and the second diaphragm D202 extend radially about a common axis of rotation D103 and are angled relative to each other. In this embodiment, the first diaphragm D201 and the second diaphragm D202 extend in opposite directions such that they are approximately 180 degrees apart. The diaphragms D201 and D202 are uniformly spaced about the axis of rotation D103. In some embodiments, diaphragm structure D200 may comprise a single diaphragm or two or more diaphragms extending radially at varying angles, which may or may not be uniformly spaced about the axis of rotation D103.

[0497] Each diaphragm may have a particular construction according to any of the diaphragm embodiments or variations described herein, for example, in connection with the first or second embodiment. In the illustrated example, each diaphragm D201, D202 has a substantially rigid construction with a diaphragm body D207, D208 formed from a substantially rigid material, such as polystyrene foam. The diaphragm body D207, D208 has a substantially thick, varying thickness, as described earlier, for example, in connection with the first embodiment. In this example, each body D207, D208 has a tapered thickness that decreases from a base end adjacent the diaphragm base structure D203 to an end D211, D212 distal from the diaphragm base D203. The taper angle is substantially uniform along the length of each diaphragm body D207, D208. In some embodiments, the thickness profile may be substantially uniform along the length of the diaphragms D201, D202, or alternatively, each diaphragm D201, D202 may have a varying thickness profile, for example, similar to any of those described in connection with the first or second embodiments.

[0498] Each diaphragm D201, D202 further includes a vertical stress stiffener D204, D205 coupled to each of the primary radiating surfaces D201a / b, D202a / b of the diaphragm D201, D202 to resist tensile and compressive forces experienced by the diaphragm body D207, D208 during operation. The vertical stress stiffeners D204, D205 for each diaphragm D201, D202 may be formed from a substantially rigid material and may have a varying mass profile similar to that described in connection with the first and second embodiments. In this example, each vertical stress stiffener D204, D205 includes a plurality of struts. The struts reduce mass in a region distal to the diaphragm base D203 and proximal to the ends D211, D212. For example, the thickness and / or width of each strut may decrease in thickness in a region distal to the diaphragm base D203. Additional stiffening plates D205, D206 may be provided on the main radiating surfaces D201a / b, D202a / b of each diaphragm D201, D202 at the base end D203.

[0499] In some embodiments, the diaphragm structure D200 may further comprise an internal stress stiffener embedded within each diaphragm body D207, D208. The internal stress stiffener may be, for example, similar to that described in connection with the first embodiment.

[0500] The diaphragm structure D200 is disposed between the diaphragms D201 and D202 and includes a diaphragm base structure D203 extending around and along the axis of rotation D103. A diaphragm-side transduction component D109 is rigidly coupled to the diaphragm base structure D203. In this embodiment, the diaphragm-side transduction component is a coil D109. In some embodiments, it may be a magnet D110 or a magnet assembly. The coil D109 is rigidly coupled to and extends around an inner coil former D111. The inner coil former D111 is substantially hollow to accommodate the inner magnet D110 of the transduction mechanism therein, as shown in FIG. 12E. The former D111 may be formed from aluminum or another suitable material with weak ferromagnetic properties. The coil D109 and former D111 are positioned about the axis of rotation D103 of the diaphragm structure D200 to provide or transfer a substantially pure torque from or to the translation mechanism during operation.

[0501] In this embodiment, the diaphragm base structure D203 further includes a first outer former component D112a coupled to the first and second diaphragms D201 and D202, and a second outer former component D112b coupled to the first and second diaphragms D201 and D202. The first outer former component D112a includes a central arched plate D113a and a pair of substantially flat plates D205a and D206a extending from either side of the arched plate D113a. The arched plate D113a is rigidly coupled to one long side D109a of the coil D109. The flat plates D205a and D206a are rigidly coupled to the first major surfaces D201a, D202a of the first and second diaphragms D201 and D202 via their respective outer stiffeners D203 and D204. In this manner, the plates D205a and D206a may form part of the outer normal stress stiffeners and extend partially from the base end D203 along the respective first major surfaces of each diaphragm D201, D202 to strengthen the base. The second outer former component D112b comprises a central arched plate D113b and a pair of substantially flat plates D205b and D206b extending from either side of the arched plate D113b. The arched plate D113b is rigidly coupled to the opposite side D109a, over one long side D109b of the coil D109. The flat plates D205b and D206b are rigidly coupled to the second major surfaces D201b, D202b of the first and second diaphragms D201, D202 via their respective outer stiffeners D203 and D204. In this manner, plates D205b and D206b may form part of an outer normal stress stiffener and extend partially from the base end along the respective second major surface D201b, D202b to strengthen the base of each diaphragm D201, D202. Outer formers D112a and D112b are formed from a substantially rigid material, such as aluminum or other metallic material, to strengthen and rigidly connect diaphragms D201 and D202.

[0502] In this embodiment, a first plurality of arcuate reinforcements D114a are distributed along the length of the coil D109 on one side of the coil D109, and a second plurality of arcuate reinforcements D114b are distributed along the length of the coil D109 on the opposite side of the coil D109. The reinforcements are rigidly coupled around the inner former D111 along the length of the former D110. The first plurality of reinforcements D114a are rigidly coupled between a first long side D109a of the coil D109 and a second long side D109b of the coil D109. The second plurality of reinforcements D114b are rigidly coupled between the first long side D109a of the coil D109 and a second long side D109b of the coil D109. The diaphragm 201 is rigidly coupled at its base end D203 to the outside of the stiffener D114a via a corresponding concave surface D201c, and the diaphragm D202 is rigidly coupled at its base end D203 to the outside of the stiffener D114b via a corresponding concave surface D202c. The stiffeners D114a and D114b are configured to stiffen the connection between the diaphragms D201, D202 and the coil D109, and are preferably formed from a substantially rigid material such as carbon fiber.

[0503] As described in connection with the first embodiment and shown in Figure 12D, the ends D211, D212 of each diaphragm D201, D202 may be partially or completely free of physical connection with the interior D105a of the surrounding structure D105 that is immediately adjacent the ends D211, D212 of the diaphragms D201, D202. A fluid gap, such as an air gap, may separate the interior of the surrounding structure D105 from the ends D211, D212 of each diaphragm D201, D202.

[0504] The diaphragm structure of this embodiment may be substituted for any other diaphragm structure described herein, or may be modified in accordance with modifications or variations of any other diaphragm structure described herein.

[0505] Transducer Base Structure 12A-12E and 12K, in this embodiment, the transducer base structure D102 remains relatively stationary during operation and is configured to form a peripheral structure D105 for housing the diaphragm structure D200 therein. The transducer base structure D102 includes a plurality of internal cavities D108 and D109 shaped to house the diaphragms D201 and D202 and to allow rotational movement of the diaphragms D201 and D202 within the peripheral structure D105 during operation. Each cavity D108, D109 is shaped and sized to complement the envelope of the diaphragm periphery during operation, and therefore has a substantially arcuate profile along the area opposite the distal ends 211, 212 of the respective diaphragms D201, D202. As shown in FIG. 12I, each cavity D108, D109 may be sized to maintain a closed but physically separated fit with the peripheral edge (including ends 211, 212) of each diaphragm D201, D202 extending between major surfaces D201a / b and D202a / b.

[0506] The transducer base structure D102 comprises a pair of peripheral portions D118 and D119 that can be rigidly coupled together to assemble the transducer. When combined, the portions D118 and D119 form a pair of cavities D108 and D109 or house the diaphragms D201 and D202. Each portion D118 and D119 comprises a main body D118a, D119a and an annular flange D118b, D119b that extends around the main body D118a, D119a. The portions D118 and D119 can be coupled at the annular flanges D118b, D119b. As shown in FIG. 12A, each main body D118a, D119a comprises a pair of openings or sound ports D118c / d, D119c / d on opposite sides of the axis of rotation D103 to allow propagation of sound pressure to or from the major radial surfaces D201a / b, D202a / b of the respective diaphragms D201, D202 during operation.

[0507] The transducer base structure D102 may be coupled to the housing or baffle via flanges D118b, D119b. The base structure D102 may be rigidly coupled to the baffle or housing or may be coupled via a suspension system, such as a decoupling mounting system as described in relation to the first embodiment and its possible variations.

[0508] The components of the magnet assembly, including the inner magnet D110 and the outer pole pieces D221-D224, are rigidly coupled to the interior of transducer base structure portions D118, D119, as described in more detail below.

[0509] The transducer base structure of this embodiment may be substituted for any other transducer base structure described herein, or may be modified in accordance with modifications or variations of any other transducer base structure described herein.

[0510] diaphragm suspension 12F-12J and 12P, the diaphragm structure D200 is coupled to the transducer base structure D102 via a diaphragm suspension. The diaphragm suspension comprises a pair of flexible mounts D230 and D240 formed from a substantially flexible material, such as a polyurethane elastomer. In some embodiments, the suspension may comprise a single or more than three flexible mounts. Each flexible mount D230 and D240 may take the form of any one of the mounts described herein. In this example, each mount D230 and D240 comprises a body having a central base portion D231, D241 and a plurality of spaced-apart spokes D232, D242 extending radially from the central base portion D231, D241, as shown in FIG. 12J. Annular end walls D233, D243 may extend around the central base and connect the ends of the spokes 232, 242. One or more cavities 234, 244 extend between the spokes 232, 242. The cavities may be filled with a fluid such as air, or they may comprise a material that is substantially less dense than the main body of the mount.

[0511] The central base portion D231, D241 of each mount D230, D240 is configured to rigidly couple to the diaphragm structure D200 via corresponding pins D116a and D116b extending laterally from the diaphragm base structure D203. The pins D116a and D116b extend from either side of the diaphragm structure D200 and are substantially coaxial with the axis of rotation D103. Each pin D116a and D116b may be coupled to and extend laterally from a respective short side of the coil D109. The outer annular walls D233, D234 of each mount D230, D240 are rigidly coupled to the interior of the transducer base structure D102 via mounting blocks D117a, D117b. Each mount D230, D240 may be coupled to a respective portion D118, D119 of the transducer base structure D102 via a mounting block D117a, D117b, each mounting block D117a, D117b including a recess or opening D117c for snugly receiving a corresponding hinge mount D230, D240, as shown in FIG.

[0512] The diaphragm suspension of the present embodiment may be substituted for any other diaphragm suspension described herein, or may be modified in accordance with modifications or variations of any other diaphragm suspension described herein.

[0513] Conversion mechanism 12E and 12F, the conversion mechanism is an electromagnetic mechanism comprising a magnet assembly including an inner magnet D110 and a pair of outer magnets D221 and D222 coupled via pole pieces D223 and D224. The inner magnet D110 and the outer magnets D221 and D222 may be permanent magnets or DC electromagnets. In this example, permanent magnets are used. The inner permanent magnet D110 is disposed within the hollow interior of the inner former D111 and overlaps the diaphragm structure D200 in the direction of the rotation axis D103. In this embodiment, the inner magnet D110 has a convex outer surface facing the diaphragm. The magnet D110 also has an opposing convex outer surface.

[0514] The inner magnet D110 includes opposing magnetic poles D110a and D110b extending along the length of the magnet D110. The magnetic poles D110a and D110b are oriented such that the direction D110c of the main magnetic field through the magnet D110 is along an axis substantially perpendicular to the axis of rotation D103. The direction of the main internal magnetic field D110c of the magnet D110 may also be substantially perpendicular to the coronal plane of at least one or each of the diaphragms D201, D202 or the coronal plane of the diaphragm structure D200. Alternatively, or in addition, the direction D110c may be substantially parallel to the sagittal direction of at least one or each of the diaphragms D201, D202 or the sagittal direction of the diaphragm structure D200. The inner magnet D110 is rigidly coupled to the interior of the transducer base structure. In this example, opposing ends of the magnet 110 couple to the interior of the transducer base structure D102 via mounting blocks D117a and D117b. For example, support rods or pins D115 may extend longitudinally from either end of the magnet and rigidly couple to corresponding openings in the corresponding mounting blocks D117a, D117b.

[0515] The outer magnets D221 and D222 are positioned outside the coil D109 at either end of the inner magnet D110. The magnets are located adjacent to the short ends of the coil D109, between the long ends D109a and D109b. The outer magnets D221 and D222 have magnetic poles oriented such that the direction of the primary magnetic field in each magnet D221a, D222a faces the direction of the inner magnet D110. The outer magnets D221 and D222 may be rigidly coupled to each other via opposing pole pieces D223 and D224. The pole pieces D223 and D224 are formed from a ferromagnetic material and extend in a direction substantially parallel to the inner magnet D110 and the rotation axis D103. The outer magnets D221 and D222 and pole pieces D223 and D224 are rigidly coupled to the interior of the transducer base structure D102 via the inner surfaces / formations of the peripheries D118 and D119.

[0516] As shown in FIG. 12E, a fluid gap, such as an air gap D225, exists between each outer pole piece D223, D224 and the corresponding outer former D112a, D112b of the coil assembly. Similarly, a fluid gap, such as an air gap, exists between the inner magnet D110 and the inner former D111. In this manner, the coil D109 is permitted to rotate relative to the magnet D110 and the pole pieces D223 and D224 during operation. As shown in FIGS. 12E and 12F, the inner magnet D110 is magnetized in the direction of the arrow "S" to "N," and magnetic flux travels in this direction through the long side D109a of the coil to the first pole piece D223. The pole piece D223 guides magnetic flux in both lateral directions toward each of the two outer magnets D221a and D222a. Each outer magnet is magnetized in the opposite direction to the inner magnet D110, so that magnetic flux travels from pole piece D223 through the side magnets in the direction of the arrows "S" to "N" in FIG. 12F to the second pole piece D224. This pole piece directs magnetic flux inward in both directions, away from the two outer magnets D221a and D222a and toward its center. When magnetic flux travels from the second pole piece D224 through the long side D109b of the coil and into the inner magnet D110, the magnetic flux circuit is completed. An audio signal is induced in the coil as an alternating current. As the two long sides D109a and D109b of the coil pass through the magnetic flux, a corresponding torque is created that rotates the diaphragm back and forth about its axis of rotation D103.

[0517] 4. Transducer of the Fourth Embodiment 13A-13P, a fourth audio transducer embodiment E100 is shown comprising a substantially rigid diaphragm structure E200 mounted to a substantially rigid base structure E102 via a diaphragm suspension. The diaphragm suspension rotatably mounts the diaphragm structure E200 relative to the base structure E102 such that the diaphragm structure E200 is configured to rotatably vibrate about an axis of rotation E103 during operation.

[0518] In this embodiment, the diaphragm suspension is configured such that the axis of rotation E103 is substantially coaxial with the nodal axis E104 of the diaphragm structure E200. The nodal axis may be predetermined or may be determined during assembly of the transducer E100, for example, according to the method described in connection with the first embodiment. In this example, the nodal axis and the axis of rotation E103 are substantially coaxial with the center of mass axis of the diaphragm structure E200. In some embodiments, the diaphragm suspension may be configured such that the axis of rotation E103 is substantially perpendicular to the coronal plane of at least one diaphragm of the structure E200 and may lie in a plane that includes the nodal axis of the diaphragm structure E200, for example, as described in connection with the first embodiment.

[0519] In this embodiment, transducer E100 comprises an electromagnetic transduction mechanism comprising a coil structure comprising a pair of coils E109 and E110, and a magnet E111. The coil structure is coupled to and forms a portion of transducer base structure E102, and the magnet is coupled to and forms a portion of diaphragm structure E200. In some embodiments, the magnet may be coupled to transducer base structure E102, and the coil structure may be coupled to diaphragm structure E200. In some embodiments, the transduction mechanism may comprise a piezoelectric mechanism, an electrostatic mechanism, or any other suitable mechanism known in the art.

[0520] diaphragm structure 13L-13P, the audio transducer E100 of this embodiment comprises a multiple diaphragm construction. The diaphragm structure E200 comprises a first diaphragm E201 and a second diaphragm E202 extending from a common diaphragm base structure E203. The first diaphragm E201 and the second diaphragm E202 extend radially about a common axis of rotation E103 and are angled relative to each other. In this embodiment, the first diaphragm E201 and the second diaphragm E202 extend in opposite directions such that they are approximately 180 degrees apart. The diaphragms E201 and E202 are approximately uniformly spaced about the axis of rotation E103. In some embodiments, the diaphragm structure E200 may comprise a single diaphragm or two or more diaphragms extending radially at varying angles, which may or may not be uniformly spaced about the axis of rotation E103.

[0521] Each diaphragm may have a particular construction according to any of the diaphragm embodiments or variations described herein, for example, in connection with the first or second embodiment. In the illustrated example, each diaphragm E201, E202 has a substantially rigid construction with a diaphragm body E207, E208 formed from a substantially rigid material, such as polystyrene foam. The diaphragm bodies E207, E208 are substantially thick and have varying thicknesses, for example, as described earlier in connection with the first embodiment. In this example, each body E207, E208 has a thickness that tapers from a base end adjacent the diaphragm base structure E203 to a terminal end E211, E212 distal from the diaphragm base E203. The taper angle is substantially uniform along the length of each diaphragm body E207, E208. In some embodiments, the thickness profile may be substantially uniform along the length of the diaphragms E201, E202, or alternatively, each diaphragm E201, E202 may have a varying thickness profile, for example, similar to any of those described in connection with the first or second embodiments.

[0522] Each diaphragm E201, E202 further includes a vertical stress stiffener E204, E205 coupled to each major radiating surface E201a / b, E202a / b of the diaphragm E201, E202 to resist tensile and compressive forces experienced by the diaphragm body E207, E208 during operation. The vertical stress stiffeners E204, E205 for each diaphragm E201, E202 may be formed from a substantially rigid material and may have a varying mass profile similar to that described in connection with the first and second embodiments. In this example, the vertical stress stiffeners E204, E205 include a plurality of struts extending along the length and width of each major surface. The struts reduce mass in a region distal to the diaphragm base E203 and proximal to the ends E211, E212. For example, the thickness and / or width of each strut may be reduced in a region distal to the diaphragm base E203. Reinforcing plates E209a / b and E210a / b may be provided on the primary radiating surfaces E201a / b, E202a / b of each diaphragm E201, E202 at the base end E203 to provide additional support at the base, and the reinforcing plates E209a / b and E210a / b also rigidly couple the respective diaphragms E201, E202 to the magnet E111.

[0523] In some embodiments, the diaphragm structure E200 may further comprise an internal stress stiffener embedded within each diaphragm body E207, E208. The internal stress stiffeners may be similar to those described in relation to the first embodiment, for example.

[0524] The diaphragm structure E200 is disposed between the diaphragms E201 and E202 and comprises a diaphragm base structure E203 extending around and along the axis of rotation E103. In this embodiment, the diaphragm base structure E203 primarily comprises a diaphragm-side transduction component E111. In this embodiment, the diaphragm-side transduction component is a magnet E111. In some embodiments, it may be a coil E109, E110. The diaphragms E201 and E202 are rigidly coupled to either side of the magnet E111 along its length. A first longitudinal surface E112 of the magnet directly couples to a complementary end surface E211a of the diaphragm E201. A second longitudinal surface E113 couples to a complementary end surface E212a of the diaphragm E202. The first longitudinal surface E112 and the second longitudinal surface E113 are substantially flat to complement the flat surfaces of the diaphragm surfaces E211a and E212a. The magnet E111 may include a plurality of recessed edges or protrusions E114a-d extending longitudinally along different sides of the magnet for connecting the outer strengthening plates E209a / b on the diaphragm E201 and the outer strengthening plates E210a / b on the diaphragm E202.

[0525] A pair of pins E116a, E116b extend from either end of the magnet E111 for mounting a diaphragm suspension thereon. In this embodiment, the diaphragm suspension includes a pair of bearings. Each bearing has inner and outer bearing components that are movable relative to each other. The inner bearing components E231, E241 of each bearing 230, 240 are rigidly coupled to the respective pins E116a, E116b at either end of the magnet E111.

[0526] As described in connection with the first embodiment and shown in Figure 13D, the end E211b, E212b of each diaphragm E201, E202 may be partially or completely free of physical connection with the interior E105a of the surrounding structure E105 immediately adjacent the end E211, E212 of the diaphragm E201, E202. A fluid gap, such as an air gap, may separate the interior of the surrounding structure E105 from the end E211, E212 of each diaphragm E201, E202.

[0527] The variations described in relation to the diaphragm construction of the first or second embodiment also apply to each diaphragm of this embodiment.

[0528] Transducer Base Structure 13A-13E and 13K, in this embodiment, the transducer base structure E102 remains relatively stationary during operation and is configured to form a peripheral structure E105 for housing the diaphragm structure E200 therein. The transducer base structure E102 comprises a plurality of internal cavities E108 and E109 shaped to house the diaphragms E201 and E202 and to allow rotational movement of the diaphragms E201 and E202 within the peripheral structure E105 during operation. Each cavity E108, E109 is shaped and sized to complement the envelope of the diaphragm periphery during operation, and therefore has a substantially arcuate profile along the area opposite the distal ends E211b, E212b of the respective diaphragms E201, E202. As shown in FIG. 13I, each cavity E108, E109 may be sized to maintain a closed but physically separated fit with the peripheral edge (including ends E211b, E212b) of each diaphragm E201, E202 extending between major surfaces E201a / b and E202a / b to minimize air leakage during operation.

[0529] The transducer base structure E102 comprises a pair of peripheral portions E118 and E119 that can be rigidly coupled together to assemble the transducer. When combined, the portions E118 and E119 form a pair of cavities E108 and E109 to accommodate the diaphragms E201 and E202. Each portion E118 and E119 comprises a main body E118a, E119a and an annular flange E118b, E119b that extends around the main body E118a, E119a. The portions E118 and E119 can be coupled at the annular flanges E118b, E119b. As shown in Figure 13A, each main body E118a, E119a comprises a pair of openings or sound ports E118c / d, E119c / d on opposite sides of the axis of rotation E103 to allow propagation of sound pressure to or from the major radial surfaces E201a / b, E202a / b of the respective diaphragms E201, E202 during operation. Each part E118 and E119 may be formed from a substantially rigid material, such as a hard plastic or metallic material.

[0530] As shown in FIG. 13B, at least one coil is coupled to the interior of the transducer base structure E102 to cooperate with the magnet E111 during operation. In this embodiment, a pair of coils E109 and E110 are coupled to the interior of the transducer base structure E102. In some embodiments, a single coil or three or more coils may be used. Each coil E109, E110 extends around the magnet E111. While the coils E109, E110 are directly adjacent to each other in this embodiment, they may be spaced apart in alternative embodiments. Each coil E109, E110 is preferably substantially rigid and rigidly coupled to the interior of the base structure E102. The longer side of each coil extends along an axis substantially parallel to the axis of rotation E103 and / or the longitudinal axis of the magnet E111.

[0531] In some embodiments, the transducer base structure E102 or other surrounding structure E105 or housing may include reinforced wall regions facing the ends E211b, E212b of each diaphragm. The reinforced regions may have substantially thicker walls, one or more reinforcing ribs, and / or more rigid material relative to other regions of the base or surrounding structure. In this embodiment, for example, the regions E106, E107 of the surrounding structure E105 facing the ends E211b, E212b of each diaphragm E201, E202 include reinforcing ribs E106a, E107a extending laterally from the regions E106, E107 to reinforce the regions facing the respective diaphragms E201, E202. Multiple ribs may be used in some embodiments. The ribs E106a, E107a may preferably extend outward from the surrounding structure E105, away from the corresponding diaphragms E201 and E202. This feature may be incorporated into the structure surrounding the diaphragm of any one of the embodiments described herein.

[0532] diaphragm suspension 13F-13J and 13P, the diaphragm structure E200 is coupled to the transducer base structure E102 via a diaphragm suspension. The diaphragm suspension has a construction in which each hinge 230, 240 includes a pair of contact surfaces that are physically coupled to each other and movable relative to each other to rotate the diaphragm during operation. In this embodiment, the suspension includes a pair of bearings E230 and E240 disposed on either side of the diaphragm structure E200. Each bearing E230 and E240 includes an inner annular bearing member E231, E241, an outer annular bearing member E233, E243, and a plurality of balls E232, E242 rotatably held between the inner and outer bearing members. In some embodiments, the suspension may include a single bearing or more than three bearings.

[0533] Either the inner bearing member or the outer bearing member may include one or more stops to limit the relative position of each ball along the corresponding bearing. In this example, each inner bearing member E231, E241 includes multiple stops E234, E244 located on either side of each ball E232, E242 to limit the position of each ball relative to the inner bearing and urge each ball to maintain a precise relative position during operation. The stops E234, E244 may be integrally formed as raised tips along the length of each corresponding inner bearing E231, E241. Alternatively, in some embodiments, the stops E234, E244 may be formed on the inner surface of each outer bearing to limit the relative position of the balls. In this embodiment, each inner bearing member E231, E241 may include a convex outer surface E245 between adjacent pairs of stops E234, E244 to further urge each ball E232, E242 to maintain a precise relative position during operation. In some embodiments, the inner surface of each outer bearing E233, E243 may include formations that encourage the balls to maintain a precise relative position during operation.

[0534] The balls E232, E242 are formed from a substantially flexible material, such as an elastomeric material. The balls may be formed from a cast polyurethane elastomer, for example, having a Shore D hardness of approximately 70 and a Young's modulus of approximately 250 MPa. The inner and outer bearing members may also be formed from a cast polyurethane elastomer or a similar material. In this embodiment, four balls E232, E242 are used for each bearing E230, E240. In some embodiments, the diaphragm suspension may include at least one hinge joint, each having a ball bearing, where the ball bearing includes fewer than seven balls. Each hinge joint may include a ball bearing, where the ball bearing includes fewer than six balls. Each hinge joint may include a ball bearing, where the ball bearing includes fewer than five balls.

[0535] The inner bearing member E231, E241 of each bearing E230, E240 is configured to rigidly couple to the diaphragm structure E200 via corresponding pins E116a and E116b extending laterally from the diaphragm base structure E203. The pins E116a and E116b extend from either side of the diaphragm structure E203 and are substantially coaxial with the axis of rotation E103. The outer bearing member E233, E243 of each bearing E230, E240 is rigidly coupled to the inside of the transducer base structure E102.

[0536] In some embodiments, the transducer may incorporate a diaphragm centering mechanism that biases each diaphragm E201, E202 toward a neutral rotational position relative to the transducer base structure. The centering mechanism may include, for example, a resilient member such as a spring or elastomer. This helps to define the fundamental frequency of the diaphragm and can help control bass response. It may also help prevent the ball from hitting the stop during normal operation.

[0537] The diaphragm suspension of the present embodiment may be substituted for any other diaphragm suspension described herein, or may be modified in accordance with modifications or variations of any other diaphragm suspension described herein.

[0538] Conversion mechanism 13C-13E, the conversion mechanism is an electromagnetic mechanism including a magnet E111 and a pair of coils E109 and E110. The magnet E111 may be a permanent electromagnet or a direct current electromagnet. In this example, a permanent magnet is used. The permanent magnet E111 is rigidly coupled to the base end of each diaphragm E201, E202 and overlaps the diaphragm structure E200 in the direction of the rotation axis E103. The magnet E111 includes opposing magnetic poles E111a and E111b extending along the length of the magnet E111. The magnetic poles E111a and E111b are oriented such that the direction E111c of the main magnetic field passing through the magnet body is along an axis substantially perpendicular to the rotation axis E103. The direction E111c of the primary magnetic field of magnet E110 may also be substantially orthogonal to the coronal plane of at least one of the diaphragms E201, E202, or the coronal plane of diaphragm structure E200. Alternatively, or in addition, direction E111c may be substantially parallel to the sagittal direction of at least one of the diaphragms E201, E202, or the sagittal direction of diaphragm structure E200. Magnet E111 is preferably positioned such that its central longitudinal axis is substantially coaxial with the axis of rotation E103 defined by the bearings, so that a substantially pure torque is imparted to the diaphragm during operation.

[0539] A pair of coils E109 and E110 are coupled to the interior of the transducer base structure and extend around the magnet E111. Each coil E109 and E110 is longitudinal and includes a pair of opposing long sides and a pair of opposing short sides. The long sides extend longitudinally along the length of the magnet so that they are substantially parallel to the rotation axis E103. The longitudinal axis of the coil E109 is also substantially perpendicular to the primary magnetic field of the corresponding magnet E111 of the transducer mechanism. The coil axes may intersect at a central region of the magnet. The coil axes may intersect at a central region of the longitudinal axis of the magnet E111.

[0540] Each magnetic pole E111a, E111b may have a substantially convex outer surface, and the corresponding opposing outer surface of each coil E109, E110 may have a complementary concave surface.

[0541] The magnet E111 has one or more surfaces configured to couple to the corresponding surfaces of each diaphragm E201, E202. The one or more surfaces include a sufficient surface area to achieve a sufficiently rigid connection. In this embodiment, the surfaces are adjacent to and / or on the side of the magnet E111 configured to extend within the same or similar plane as the major surface of each diaphragm E201, E202. The surfaces may be directly coupled to the diaphragm's normal stress stiffener. The magnet may also be directly coupled to each diaphragm at the region of the magnet most proximal to the diaphragm. The most proximal region may be closer to the diaphragm than the adjacent coil and / or pole piece of the transducer mechanism. For example, the magnet E111 may be directly coupled to a surface of the diaphragm body configured to primarily exhibit shear deformation forces during operation (the end face of the diaphragm facing the axis of rotation). A high-temperature adhesive may be used to bond the magnet to the diaphragm. The magnet bonding surface may be nickel plated and treated with an acid such as nitric acid.

[0542] In some embodiments, the magnet E111 and each diaphragm may be coupled via one or more components configured to extend into corresponding openings or slots in one or both of the magnet and diaphragm.

[0543] The conversion mechanism of this embodiment may be replaced by any other conversion mechanism described herein, or may be modified according to modifications or variations of any other conversion mechanism described herein.

[0544] Devices incorporating transducers 14A-14D, the transducer base structure E102 may be coupled to the housing E300 or baffle via flanges E118b, E119b. The base structure E102 may be rigidly coupled to the baffle or housing, or may be coupled via a suspension, such as a decoupling mounting system E40...

Claims

1. A diaphragm and a transducer base structure; a diaphragm suspension configured to rotatably mount the diaphragm relative to the transducer base structure such that the diaphragm can rotate about an axis of rotation relative to the transducer base structure; a transduction mechanism operatively coupled to the diaphragm for converting between audio signals and sound pressure; Equipped with the diaphragm having at least one major surface extending in a single radial direction from the axis of rotation and having a profile that is substantially convex along the single radial direction of the diaphragm; 10. An audio transducer, wherein the conversion mechanism comprises a magnet coupled to the diaphragm and configured to rotate with the diaphragm about the axis of rotation during operation.

2. 2. The audio transducer of claim 1, wherein a pair of opposite major surfaces of the diaphragm each include a profile that is substantially convex along the single radial direction of the diaphragm.

3. 3. The audio transducer of claim 1, wherein the thickness of the diaphragm tapers from a central region toward an end distal to the axis of rotation, and the diaphragm has a substantially uniform thickness from a base end proximal to the axis of rotation to the central region.

4. 3. The audio transducer of claim 1, wherein the thickness of the diaphragm tapers from a central region toward an end distal to the axis of rotation, and the thickness of the diaphragm tapers from the central region toward a base end proximal to the axis of rotation, the tapered thickness decreasing from the central region toward the base end.

5. 5. An audio transducer as described in claim 3 or 4, wherein at least one major surface of the diaphragm has a first angle between the central region and the base end with respect to a first imaginary plane that bisects the diaphragm and contains the axis of rotation, and a second angle between the central region and the distal end with respect to the first imaginary plane, the absolute value of the first angle being less than the absolute value of the second angle.

6. 6. An audio transducer according to claim 3, wherein the central region is substantially centered between the axis of rotation and the distal end, or is closer to the axis of rotation than to the distal end.

7. 7. An audio transducer according to claim 1, wherein the diaphragm suspension flexibly mounts the diaphragm to the transducer base structure.

8. 8. An audio transducer according to claim 1, wherein the diaphragm suspension includes at least one hinge mount formed from a substantially flexible material.

9. 9. The audio transducer of claim 8, wherein each substantially flexible hinge mount may be substantially translationally compliant such that the hinge mount may deform substantially linearly along at least one axis.

10. 10. The audio transducer of claim 9, wherein the at least one hinge mount is formed from a material having an average Young's modulus of less than about 8 gigapascals (GPa) and / or from an elastomer or soft plastic material.

11. 10. The audio transducer of claim 9, wherein the at least one hinge mount is formed from a material having an average Young's modulus of less than about 4 gigapascals (GPa) and / or from an elastomer or soft plastic material.

12. 10. The audio transducer of claim 9, wherein the at least one hinge mount is formed from a material having an average Young's modulus of less than about 2 gigapascals (GPa) and / or from an elastomer or soft plastic material.

13. 13. An audio transducer according to any one of claims 9 to 12, wherein each hinge mount is substantially damped.

14. 14. An audio transducer according to any one of claims 9 to 13, wherein the diaphragm suspension includes at least one hinge mount having a sufficiently low Young's modulus such that the fundamental diaphragm resonant frequency is less than about 100 Hertz.

15. each hinge mount is formed from a material having a material loss factor greater than 0.005 at 30 degrees Celsius and an operating frequency of 100 Hertz; and / or 15. An audio transducer according to any one of claims 9 to 14, wherein each hinge mount is supported by a material having a loss factor greater than 0.005 at 30 degrees Celsius and an operating frequency of 100 Hertz.

16. An audio transducer as described in any one of claims 1 to 15, wherein the magnet and the diaphragm are coupled via one or more components configured to fit into corresponding openings or slots in one or both of the magnet and the diaphragm.

17. 17. An audio transducer according to any one of claims 1 to 16, wherein the transduction mechanism includes a diaphragm-side transduction component coupled along a base edge of the diaphragm.

18. 18. An audio transducer as claimed in any one of claims 1 to 17, wherein the diaphragm suspension includes at least one substantially flexible hinge mount, each hinge mount having at least one concave surface that promotes bending of the hinge at or about said surface.

19. 19. An audio transducer as claimed in any one of claims 1 to 18, wherein the diaphragm suspension includes at least one hinge mount, each hinge mount including a pair of flexible hinge elements angled relative to each other.

20. The magnet has one or more surfaces configured to couple to corresponding surfaces of the diaphragm; 20. An audio transducer as described in any one of claims 1 to 19, wherein the surface of the magnet is provided adjacent to the at least one major surface of the diaphragm and / or on a side of the magnet configured to extend in the same or similar plane as the at least one major surface of the diaphragm.

21. An audio transducer as described in claim 9, wherein the diaphragm comprises a diaphragm body and a vertical stress stiffener coupled to the diaphragm body at or near at least one of the major surfaces, the vertical stress stiffener being adapted to resist compressive-tensile stresses experienced by the diaphragm body at or near the major surface during operation, and the surface of the magnet being directly coupled to the vertical stress stiffener.

22. A diaphragm suspension system is arranged so that the axis of rotation is substantially contained within a first imaginary plane that substantially contains a nodal axis associated with the diaphragm and is substantially perpendicular to a second imaginary plane that contains a radial axis of the diaphragm body; The node axis is the diaphragm is not substantially effectively supported by the diaphragm suspension; and The diaphragm is subjected to mechanical forces associated with the conversion mechanism during use.

22. An audio transducer as claimed in any one of claims 1 to 21, wherein the second axis of rotation is a second axis about which the diaphragm rotates relative to the transducer base structure.

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