Moving magnet motor

Abstract

The present disclosure relates to a moving magnet motor. The present invention provides a moving magnet motor comprising: a stationary voice coil coupled to a frame; a moving magnet assembly movably coupled to the frame and operable to move relative to the stationary coil, the moving magnet assembly comprising a magnet and a flux concentrating member, the magnet and the flux concentrating member defining a gap within which the stationary coil is positioned; and an actuating surface coupled to the moving magnet assembly, wherein movement of the moving magnet assembly drives movement of the actuating surface along a translation axis.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application is a non-provisional application of co-pending U.S. Provisional Patent Application No. 63 / 174,942, filed on April 14, 2021, and is incorporated herein by reference. Technical Field

[0003] One aspect of the present disclosure is directed to a moving magnet electric machine including a moving magnet electric machine having a magnet assembly that moves relative to a coil to focus a magnetic field over the coil and reduce opposing magnetic field effects. Other aspects are also described and claimed. Background Art

[0004] In modern consumer electronics, audio functionality is playing an increasingly important role, driven by continuous improvements in digital audio signal processing and audio content delivery. A wide range of consumer electronic devices can benefit from improved audio performance. For example, portable devices using electrodynamic transducers with mobile motor systems can benefit from improved performance. For example, while mobile motor systems can offer the advantage of using larger coils than non-mobile motor systems, they can be less efficient because they use an open magnetic path around the magnets, without a focused magnetic field region. This, in turn, results in opposing magnetic flux flowing through the same coils that are generating the Lorentz force to excite the diaphragm. At large excursions, there's no significant flux density across the coils, which introduces distortion because the positive and negative Lorentz forces nearly cancel each other out. Summary of the Invention

[0005] One aspect of the present disclosure relates to improvements to moving magnet motors, such as speaker motors. Typically, moving magnet speakers are designed to move the motor using stray flux density from magnets that are not part of a closed magnetic circuit. When the magnets are used outside the magnetic circuit, their ability to focus the flux density is very poor. The operating point of the magnets in free space is very low, so even at high temperatures, it is not possible to protect the magnets from demagnetization. Therefore, when speakers are made with moving magnets without any flux guiding elements, the opposing flux also excites the same coils of the diaphragm by generating Lorentz forces. At large excursions, there is no main flux density on the coils, which will introduce distortion because the positive and negative Lorentz forces almost cancel each other.

[0006] Therefore, the present disclosure provides a moving magnet motor having a closed magnetic circuit configured to focus magnetic flux density on a coil that travels above the coil, driving the movement of an actuating surface (e.g., a speaker diaphragm). This configuration results in an opposing magnetic field that is very small compared to the primary flux density on the coil, enabling large excursion and low distortion values. To achieve this, one or more radially polarized magnets are positioned close to the voice coil (e.g., inner and outer coils having the same winding height), and the magnets' magnetic flux lines are concentrated on one or more flux concentrating members made of a soft magnetic material (e.g., steel) positioned along the other side of the voice coil. The polarized magnets and the soft magnetic material are part of the same moving mass, so the soft magnetic material follows the movement of the magnets. The moving mass is in turn connected to the actuating surface (e.g., a speaker diaphragm) so that its movement drives the movement (e.g., vibration) of the actuating surface. Because the highest concentration of flux density occurs between the soft magnetic material and the magnets, the primary magnetic flux density moves with the moving assembly without being significantly reduced by the position of the diaphragm. This dominant flux density region moving across the voice coil allows for larger excursions of the actuating surface (e.g., diaphragm) without observable back-field interference. This is because the magnitude of the back-field becomes very small compared to the dominant flux density between the hard and soft magnetic components. This allows for a moving magnet motor system for driving an actuating surface with large excursions and low distortion.

[0007] Representatively, in one aspect, a moving magnet motor includes a fixed voice coil coupled to a frame; a moving magnet assembly movably coupled to the frame and operable to move relative to the fixed coil, the moving magnet assembly including a magnet and a flux concentrating member, the magnet and the flux concentrating member defining a gap within which the fixed coil is positioned; and an actuating surface coupled to the moving magnet assembly, wherein movement of the moving magnet assembly drives movement of the actuating surface along a translation axis. The fixed coil can be a continuous voice coil. The fixed coil can be an annular voice coil with the magnet radially inwardly of the voice coil and the flux concentrating member radially outwardly of the voice coil. In other aspects, the flux concentrating member can be radially inwardly of the voice coil and the magnet radially outwardly of the voice coil. The magnet can be a radially polarized magnet. The flux concentrating member can be a steel structure. In other aspects, the flux concentrating member can be a radially polarized magnet. In some aspects, the flux concentrating member is a first flux concentrating member, and the moving magnet assembly also includes a second flux concentrating member directly coupled to the magnet. In other aspects, the stationary coil is a first stationary voice coil, and the assembly further includes a second stationary voice coil positioned radially outward of the first stationary voice coil. In some aspects, the first and second stationary voice coils have the same current direction and the same orientation. In some aspects, the flux concentrating member is positioned between the first and second stationary voice coils, the magnet is a first radially polarized magnet, the moving magnet assembly further includes a second radially polarized magnet, and the first radially polarized magnet is positioned radially inward of the first stationary voice coil, and the second radially polarized magnet is positioned radially outward of the second stationary voice coil. In other aspects, the magnet is positioned between the first and second stationary voice coils, the flux concentrating member is a first flux concentrating member, the moving magnet assembly further includes a second flux concentrating member, and the first flux concentrating member is positioned radially inward of the first stationary voice coil, and the second flux concentrating member is positioned radially outward of the second stationary voice coil.

[0008] In another aspect, a loudspeaker magnet motor assembly includes a fixed portion comprising a continuous voice coil fixedly coupled to a frame; and a movable portion comprising a diaphragm and a magnet assembly movably coupled to the frame, the magnet assembly having a first magnet member and a second magnet member operable to focus magnetic flux density toward the continuous voice coil and translate along the continuous voice coil to drive the diaphragm along a translation axis. The magnet assembly may have a displacement range along the translation axis, the displacement range being defined by the height of the continuous voice coil. In some aspects, the first magnet member is a radially polarized magnet and the second magnet member is a steel member positioned on opposite sides of the continuous voice coil. In some aspects, the first and second magnet members define a gap within which the continuous voice coil is positioned. In some aspects, the movable portion further includes a third magnet member directly attached to the first or second magnet member. In other aspects, the continuous voice coil is a first continuous voice coil, and the fixed portion further includes a second continuous voice coil. In some aspects, the second magnet member can be a steel structure positioned between the first and second continuous voice coils, the moving portion further comprising a third magnet member, wherein the first and third magnet members are positioned along opposite sides of the first and second continuous voice coils from the second magnet member. The moving portion can further comprise a third magnet member, wherein the first, second, and third magnet members are radially polarized magnets positioned along different sides of the first and second continuous voice coils. In another aspect, the first magnet member is a radially polarized magnet positioned between the first and second continuous voice coils, the moving portion further comprising a third magnet member, wherein the second and third magnet members are steel structures positioned along different sides of the first and second continuous voice coils.

[0009] In another aspect, an electronic device includes an electronic device housing, a moving magnet motor coupled to the electronic device housing, and an actuation surface. The moving magnet motor may include a stationary voice coil and a moving magnet assembly operable to move relative to the stationary voice coil. The moving magnet assembly may include a magnet and a flux concentrating member defining a gap within which the stationary coil is positioned. In some aspects, the moving magnet motor is a speaker moving magnet motor, and the actuation surface is a speaker diaphragm. In some aspects, the actuation surface is a housing wall of the electronic device housing.

[0010] In some aspects, a moving magnet motor of any of the aforementioned configurations can be a speaker moving magnet motor or shaker integrated into a portable electronic device.

[0011] The above summary does not include an exhaustive list of all aspects of the present disclosure. It is contemplated that the present invention includes all systems and methods that can be implemented by all suitable combinations of the various aspects summarized above and disclosed in the detailed description below and particularly pointed out in the claims filed with this patent application. Such combinations have particular advantages not specifically recited in the above summary. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In the drawings, several aspects are shown by way of example and not limitation, in which like reference numerals indicate like elements. It should be noted that reference to "one" or "an" aspect in this disclosure is not necessarily the same aspect and means at least one.

[0013] Figure 1 A cross-sectional side view of one aspect of a moving magnet electric machine assembly is shown.

[0014] Figure 2 A schematic cross-sectional side view of another aspect of a moving magnet electric machine assembly is shown.

[0015] Figure 3 A schematic cross-sectional side view of another aspect of a moving magnet electric machine assembly is shown.

[0016] Figure 4 A schematic cross-sectional side view of another aspect of a moving magnet electric machine assembly is shown.

[0017] Figure 5 A schematic cross-sectional side view of another aspect of a moving magnet electric machine assembly is shown.

[0018] Figure 6 A schematic cross-sectional side view of another aspect of a moving magnet electric machine assembly is shown.

[0019] Figure 7 A schematic cross-sectional side view of another aspect of a moving magnet electric machine assembly is shown.

[0020] Figure 8 A schematic cross-sectional side view of another aspect of a moving magnet electric machine assembly is shown.

[0021] Figure 9 A schematic cross-sectional side view of another aspect of a moving magnet electric machine assembly is shown.

[0022] Figure 10 A schematic cross-sectional side view of another aspect of a moving magnet electric machine assembly is shown.

[0023] Figure 11 A schematic cross-sectional side view of another aspect of a moving magnet electric machine assembly is shown.

[0024] Figure 12 Shown is a simplified schematic diagram of electronics in which a transducer assembly may be implemented.

[0025] Figure 13 A block diagram illustrating some of the components of an electronic device in which a transducer assembly may be implemented is shown. DETAILED DESCRIPTION

[0026] In this section, we will explain several preferred aspects of the present disclosure with reference to the accompanying drawings. Unless the shapes, relative positions, and other aspects of the components described in these aspects are explicitly defined, the scope of the present disclosure is not limited solely to the components shown, which are provided for illustrative purposes only. Furthermore, while numerous details are set forth, it should be understood that some aspects of the present disclosure may be practiced without these details. In other cases, well-known structures and techniques are not shown in detail to avoid obscuring the understanding of this description.

[0027] The terms used herein are only for the purpose of describing specific aspects and are not intended to limit the present disclosure. Spatially relative terms, such as "under...", "below...", "below...", "above...", "on...", etc., may be used herein for the convenience of description to describe the relationship between an element or feature and another one or more elements or one or more features, as shown in the accompanying drawings. It should be understood that spatially relative terms are intended to cover different orientations during use or operation of the device other than the orientation shown in the accompanying drawings. For example, if the device in the figure is turned over, the element described as "below" or "below" other elements or features can then be oriented to be "above" other elements or features. Therefore, the exemplary term "below..." can cover both orientations of "above..." and "below...". The device can be oriented in other ways (e.g., rotated 90 degrees or at other orientations), and the spatially relative descriptors used in this article are interpreted accordingly.

[0028] As used herein, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context indicates otherwise. It should be further understood that the terms "include," "comprise," and "comprising" specify the presence of stated features, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and / or groups thereof.

[0029] As used herein, the terms "or" and "and / or" should be interpreted as inclusive or meaning any one or any combination. Thus, "A, B, or C" or "A, B, and / or C" means "any of the following: A; B; C; A and B; A and C; B and C; A, B, and C." An exception to this definition occurs only when a combination of elements, functions, steps, or actions are inherently mutually exclusive in some way.

[0030] Figure 1 A cross-sectional view of a moving magnet motor assembly is shown. In one aspect, for example, assembly 100 can be a moving magnet motor integrated in an electric or electroacoustic transducer that converts electrical signals into vibration and / or sound signals that can be output from the device in which assembly 100 is integrated. For example, assembly 100 can be a speaker moving magnet motor. On the other hand, assembly 100 can be a shaker for actuating or vibrating any type of surface or structure coupled thereto to provide, for example, a tactile output. For example, assembly 100 can be a speaker and / or shaker integrated into a smartphone or other similar portable electronic device. In some cases, assembly 100 can be attached to a surface of a device to actuate (e.g., vibrate) the surface. Assembly 100 can be enclosed in a housing or casing of the device, integrated within the housing or casing.

[0031] Assembly 100 may generally include a frame 102, a fixed portion 104, and a mobile portion 106 that moves relative to fixed portion 104 and frame 102. Frame 102 may be any type of support structure that can support the components of the assembly and is used to integrate the assembly into a surrounding device (e.g., a portable electronic device). In some aspects, frame 102 may be part of the housing of the device into which assembly 100 is integrated. In one aspect, fixed portion 104 may include one or more coils 108 fixedly connected to frame 102. One or more coils 108 may be, for example, voice coils formed from windings of copper wire. Voice coil 108 may be mounted at one end to a bottom wall or side 110 of frame 102. In this aspect, the voice coil may have a winding height that extends vertically or parallel to the z-height of assembly 100, as shown. The other end (e.g., the top end) of coil 108 may be free of and not directly attached to any other structure or component of assembly 100. During operation, coil 108 may be powered by current in a desired direction and used to drive movement of mobile portion 106.

[0032] The moving portion 106 may include a first magnet member 112 and a second magnet member 114, which together define a gap 116 within which the coil 108 is positioned. The first magnet member 112 and the second magnet member 114 may form a closed magnetic circuit that focuses magnetic flux density toward the coil 108. In this regard, when current is applied to the coil 108, the coil reacts to the magnetic field from the closed magnetic circuit, causing the first magnet member 112 and the second magnet member 114 to move or translate along a translation axis 122, as indicated by the arrows. The translation axis 122 may, for example, be parallel to the z-axis of the assembly 100. In some aspects, the translation axis 122 may be considered to extend in an axial direction and may define an axis of symmetry for the assembly 100. In other aspects, the translation axis 122 may be considered to extend parallel to or in the same direction as the height of the windings of the coil 108 or the height of the gap 116 defined by the first magnet member 112 and the second magnet member 114. First and second magnet members 112, 114 are in turn connected to an actuating surface 118, which is coupled to frame 102 via suspension member 120. Because first and second magnets 112, 114 are part of the same moving mass, they move together and drive actuating surface 118 along translation axis 122. Because the highest concentration of magnetic flux density occurs between first and second magnet members 112, 114, the primary magnetic flux density moves with the moving mass without significantly decreasing depending on the location of actuating surface 118 coupled thereto. This primary flux density region moving above coil 108 allows for greater excursion of actuating surface 118 (e.g., a diaphragm) without the observed reverse magnetic field interference described above. Thus, assembly 100 achieves a moving magnet motor system that drives an actuating surface with large excursions and low distortion values.

[0033] Referring now in more detail to the first magnet assembly 112 and the second magnet assembly 114, in some aspects, at least one of the first magnet assembly 112 and / or the second magnet assembly 114 can be a polarized magnet. The polarized magnet can be a radially polarized magnet that is oriented within the assembly such that the north pole and the south pole are radially arranged relative to the translation axis 122. In other words, as Figure 1As shown, facing the left or right side. In another aspect, one of the first magnet member 112 or the second magnet member 114 can be a flux concentrating member or structure that can be operated to focus the magnetic flux lines of a polarized magnet (e.g., magnet member 112 or 114). Representatively, one of the first magnet member 112 or the second magnet member 114 can be a soft magnetic material, such as steel that can be operated to focus the magnetic flux lines. For example, in one aspect, the first magnet member 112 can be a radially polarized permanent magnet and the second magnet member 114 can be a non-polarized steel member that moves along the coil 108 with the first magnet member 112 to focus the magnetic flux lines toward the coil 108. In another aspect, the second magnet member 114 can be a radially polarized magnet and the first magnet member 112 can be a non-polarized steel member. In other aspects, both the first magnet member 112 and the second magnet member 114 can be radially polarized magnets that move along the coil 108 to focus the magnetic flux lines. However, in all cases, at least one of the first magnet member 112 or the second magnet member 114 should be a radially polarized magnet positioned along one side of the coil 108, and the other of the first magnet 112 or the second magnet 114 should be a structure that can focus the magnetic flux lines toward the coil 108 (e.g., a radially polarized magnet or a soft magnetic material such as steel).

[0034] Referring now in more detail to the actuation surface 118, the actuation surface 118 can be, for example, a sound radiating surface, such as a speaker diaphragm that is caused to vibrate and output sound by the moving members 112, 114. In other aspects, the actuation surface 118 can be any type of surface that needs to move or vibrate. For example, in other aspects, the actuation surface 118 can be a wall of a housing or shell, such as a shell of a device in which the assembly 100 is integrated, or another surface or structure that can be used to create, for example, a tactile output felt by a user. The suspension member 120 can be a relatively compliant structure that is strong enough to suspend the first magnet 112, the second magnet member 114, and the actuation surface 118 from the frame 102 while also allowing each of these components to move relative to the coil 108 and the frame 102. For example, the first magnet member 112 and the second magnet member 114 can be attached to each other via a connecting member 122 (e.g., a bracket, a fastener, etc.), and the actuating surface 118 and / or the suspension member 120 can be connected to the first member 112 or the second member 114 via another connecting member 124 (e.g., a bracket, a fastener, etc.).

[0035] In addition, although an assembly including a single coil 108, a first magnet member 112, and a second magnet member 114 is shown, any number of coils and / or magnet members can be envisioned. For example, the assembly 100 can include a pair of coils 108, a pair of first magnet members 112, and / or a pair of second magnet members 114. In addition, it is envisioned that the coil 108, the first magnet member 112, and the second magnet member 114 can be annular components. For example, the coil 108, the magnet member 112, and the magnet member 114 can have a circular, oval, or racetrack shape. In this regard, the first magnet member 112 can be considered to be an inner magnet member 112 surrounded by the coil 108, and the second magnet member 114 can be considered to be an outer magnet member surrounding the coil 108. In other words, the first magnet member 112 can be considered to be radially inside the coil 108, the coil 108 can be radially inside the second magnet member 114, and the second magnet member 114 can be radially outside the coil 108.

[0036] Now refer to Figures 2 to 11 Various magnet member / coil configurations for assembly 100 are described in greater detail. Figures 2 to 11 The right hand side cross-sectional views of the various assembly configurations are shown. It will be appreciated that the assembly is symmetrical and therefore the left hand side (not shown) will be Figures 2 to 11 For example, the translation axis 122 shown in each of the figures can be considered as an axis of symmetry, and the assembly is considered to be symmetrical about this axis of symmetry. In addition, it should be noted that for ease of explanation, Figures 2 to 11 However, the omitted aspects should be understood to be included in Figures 2 to 11 The complete assembly, as previously referenced Figure 1 discussed.

[0037] Now see Figure 2 , Figure 2200 is shown having a fixed portion 104 including a pair of coils 208A, 208B and a mobile portion 106 including a pair of first magnet members 212A, 212B and a second magnet member 214. As previously described, the mobile portion 106 (e.g., the first magnet members 212A-B and the second magnet member 214) moves relative to the fixed portion 104 (e.g., the coils 208A-B). In particular, each of the first magnet members 212A-B and the second magnet member 214 translates together along the translation axis 122 relative to the coils 208A-B, as indicated by the arrows. Both of the first magnet members 212A-B can be radially polarized magnets with their poles oriented in the same direction shown. The second magnet member 214 can be a flux concentrating member (e.g., a soft magnetic material such as steel) that concentrates the magnetic flux lines 224 generated by the first magnet members 212A-B within an area of ​​concentrated or focused magnetic flux density 226. In this regard, when the first and second magnet members 212A-B and 214 are translated together along the coils 208A-B, these coils are positioned within the gaps 216A, 216B formed by the magnet members, and the region 226 of focused flux density also travels along the height of the windings of the coils 208A-B. Thus, the primary region of magnetic flux density can be maintained along the entire height of the coils 208A-B. This, in turn, enables greater excursion of the actuating surface (e.g., actuating surface 118) connected to the moving portion 106 without observing reverse magnetic field interference.

[0038] Referring now to the pair of coils 208A-B in more detail, coils 208A-B can, in some aspects, be separate voice coils, each having a winding height extending parallel to the z-axis or in the z-height direction as shown. Depending on the requirements of, for example, the associated loudspeaker, coils 208A-B can be connected in series or in parallel with the same current direction, so that they are constructive. Both coils 208A-B should have the same orientation (e.g., both coils are in-plane, or both coils are out-of-plane). Coils 208A-B can have the same winding height as shown, which, in some cases, can be greater than the height of the magnetic assembly of the moving part 106 and the gaps 216A-B as shown. In other aspects, coils 208A-B can have different winding heights. However, each of coils 208A-B can be considered a continuous coil in that they have a continuous and uninterrupted winding height, in some cases formed from a single copper wire. In other words, coils 208A-B are not formed from coil sections or segments stacked one on top of another to achieve the desired overall height shown in the figure. Furthermore, as previously described, in some aspects, coils 208A-B are toroidal coils, and thus coil 208A can be considered an inner coil and coil 208B can be considered an outer coil. Alternatively, coil 208A can be considered radially inward of coil 208B, or coil 208B can be considered radially outward of coil 208A.

[0039] Similarly, the magnet members 212A-B and 214 of the moving portion 106 can be annular members (e.g., circular, oval, racetrack-shaped, etc.). In this regard, the first magnet members 212A-B can be considered as the inner and outer magnet members, respectively, and the second magnet member 214 can be the middle magnet member between the inner and outer magnet members 212A-B. Further, the coil gap 216A can be considered as the inner gap formed between the inner magnet member 212A and the middle magnet member 214, and the coil gap 216B can be considered as the outer gap formed between the middle magnet member 214 and the outer magnet member 212B.

[0040] As previously described, both first magnet members 212A and 212B can be radially polarized magnets, and second magnet member 214 can be a flux concentrating member, such as a steel structure. Each of first magnet members 212A-B and second magnet member 214 can have the same height (dimension along the z-axis), or can have different heights. For example, in another aspect, each of first magnet members 212A-B and second magnet member 214 can have different heights that decrease toward translation axis 222 (which corresponds to the axis of symmetry). Regardless of the height of first magnet members 212A-B and second magnet member 214, they can be considered to have a relatively large displacement range along the translation axis that is equal to or less than the winding height of coils 208A-B. In particular, the positive magnetic field is focused above a certain area of ​​the magnet assembly so that when it moves along coils 208A-B, it is not affected by the opposing magnetic field (weaker than the focused positive magnetic field). Therefore, the sum of the magnetic fields is not affected, and thus the force from the circuit system is not affected. Thus, because the moving portion 106 carries a positive magnetic field along the entire height of the coils 208A-B, which exceeds the opposing magnetic field, a positive force appears along the entire height of the coils, thereby allowing for an improved range of displacement. This is in contrast to an open circuit system that has no area of ​​focused magnetic flux and does not move along the coils, and thus may lose force along certain areas of the coils.

[0041] Now see Figure 3 , Figure 3 An assembly 300 is shown that is similar to the assemblies previously discussed in that it includes a fixed portion 104 and a moving portion 106 that moves relative to the fixed portion 104 along a translation axis 122. However, in assembly 300, the fixed portion 104 includes a single coil 308, and the moving portion 106 includes a single first magnet member 312 and a single second magnet member 314 that are connected together and move relative to the coil 308. The first magnet member 312 can be a radially polarized magnet positioned radially outward from the coil 308. The second magnet member 314 can be a flux concentrating member, such as a steel structure, positioned radially inward from the coil 308. As previously described, the second magnet member 314 concentrates the magnetic flux lines 324 generated by the first magnet member 312 into an area of ​​concentrated or focused magnetic flux density 326. In this regard, as the first and second magnet members 312, 314 translate along the coil 308 positioned within the gap 316 formed by the magnet members, the region of focused flux density 326 also travels along the winding height of the coil 308. Thus, as previously described, the primary region of magnetic flux density can be maintained along the entire height of the coil 308, thereby enabling greater excursion of an actuation surface (e.g., actuation surface 118) coupled to the moving portion 106.

[0042] Now see Figure 4 , Figure 41 and 2. An assembly 400 is shown that is similar to the previously discussed assemblies in that it includes a fixed portion 104 and a moving portion 106 that moves relative to the fixed portion 104 along a translation axis 122. However, in assembly 400, the fixed portion 104 includes a pair of coils 408A and 408B, and the moving portion 106 includes a single first magnet member 412 and a pair of second magnet members 414A and 414B that are connected together (and connected to an actuation surface) and move relative to the coils 408A-B. The first magnet member 412 can be a radially polarized magnet positioned between the pair of coils 408A-B. The pair of second magnet members 414A-B can be flux concentrating members, such as steel structures, positioned on opposite sides of the coils 408A-B, for example, radially inward of coil 408A and radially outward of coil 408B. As previously described, the second magnet members 414A-B concentrate the magnetic flux lines 424 generated by the first magnet member 412 into a region of concentrated or focused magnetic flux density 426. In this regard, as the first magnet member 412 and the second magnet member 414A-B translate together along the coil 408A-B positioned within the gap 416A, 416B formed by the magnet members, the focused magnetic flux density region 426 also travels along the winding height of the coil 408A-B. Thus, as previously described, the primary magnetic flux density region can be maintained along the entire height of the coil 408A-B, thereby enabling greater excursion of the actuating surface (e.g., actuating surface 118) coupled to the moving portion 106.

[0043] Now see Figure 5 , Figure 5An assembly 500 is shown that is similar to the assemblies previously discussed in that it includes a fixed portion 104 and a moving portion 106 that moves relative to the fixed portion 104 along a translation axis 122. However, in assembly 500, the fixed portion 104 includes a single coil 508, and the moving portion 106 includes a single first magnet member 512 and a single second magnet member 514 that are connected together (and connected to the actuation surface) and move relative to the coil 508. The first magnet member 512 can be a radially polarized magnet positioned radially inward of the coil 508. The second magnet member 514 can be a flux concentrating member, such as a steel structure, positioned radially outward of the coil 508. As previously described, the second magnet member 514 concentrates the magnetic flux lines 524 generated by the first magnet member 512 into an area of ​​concentrated or focused magnetic flux density 526. In this regard, as the first and second magnet members 512, 514 translate along the coil 508 positioned within the gap 516 formed by the magnet members, the region of focused flux density 526 also travels along the winding height of the coil 508. Thus, as previously described, the primary region of magnetic flux density can be maintained along the entire height of the coil 508, which in turn can enable greater excursion of an actuation surface (e.g., actuation surface 118) coupled to the moving portion 106.

[0044] Now see Figure 6 , Figure 6 An assembly 600 is shown that is similar to the previously discussed assemblies in that it includes a fixed portion 104 and a mobile portion 106 that moves relative to the fixed portion 104 along a translation axis 122. However, in assembly 600, the fixed portion 104 includes a pair of coils 608A and 608B, and the mobile portion 106 includes three first magnet members 612A, 612B, and 612C that are attached together (and to an actuation surface) and move relative to the coils 608A and 608B. The first magnet members 612A-C can be radially polarized magnets positioned between and outside the pair of coils 608A-B in the same direction (e.g., with north and south poles facing the same direction). In this regard, the first magnet members 612A-C act as flux concentrating members for each other and concentrate the magnetic flux lines 624 generated by the first magnet members 612 into an area of ​​concentrated or focused magnetic flux density 626. In this regard, as the first magnet members 612A-C translate along the coils 608A-B positioned within the gaps 616A, 616B formed by the magnet members, the focused magnetic flux density region 626 also travels along the height of the windings of the coils 608A-B. Thus, as previously described, the primary magnetic flux density region can be maintained along the entire height of the coils 608A-B, thereby enabling greater deflection of the actuating surface (e.g., actuating surface 118) coupled to the moving portion 106.

[0045] Now see Figure 7, Figure 7 An assembly 700 is shown that is similar to the previously discussed assemblies in that it includes a fixed portion 104 and a moving portion 106 that moves relative to the fixed portion 104 along a translation axis 122. However, in assembly 700, the fixed portion 104 includes a pair of coils 708A and 708B, and the moving portion 106 includes a pair of first magnet members 712A, 712B, a single second magnet member 714, and a pair of third magnet members 730A, 730B coupled to the first magnet members 712A-B, which are connected together (and connected to the actuation surface) and all move relative to the coils 708A, 708B. The first magnet members 712A-B can be radially polarized magnets positioned radially outward of the pair of coils 708A-B, and the second magnet member 714 is positioned between the coils 708A-B. The second magnetic member 714 can be a flux concentrating member (e.g., a steel structure) that concentrates the magnetic flux lines 724 generated by the first magnetic members 712A-B into an area of ​​concentrated or focused magnetic flux density 726. The third magnetic members 730A-B can be flux concentrating members that are directly attached to the surface of the first magnetic members 712A-B facing the coils 708A-B. Representatively, the third magnetic members 730A-B can be a soft magnetic material similar to the second magnetic member 714, such as steel, attached to the surface of the first magnetic members 712A-B. For example, the third magnetic member 730A can be attached to the outer surface of the first magnetic member 712A facing the coil 708A, and the third magnetic member 730B can be attached to the inner surface of the first magnetic member 712B facing the coil 708B. In this regard, when the first magnet members 712A-B and the second magnet members 714, to which the third magnet members 730A-B are attached, translate together along the coils 708A-B positioned within the gaps 716A, 716B formed by the magnet members, the focused magnetic flux density region 726 also travels along the height of the windings of the coils 708A-B. Thus, as previously described, the primary magnetic flux density region can be maintained along the entire height of the coils 708A-B, thereby enabling greater excursion of the actuating surface (e.g., actuating surface 118) coupled to the moving portion 106.

[0046] Now see Figure 8 , Figure 8An assembly 800 is shown that is similar to the assemblies previously discussed in that it includes a fixed portion 104 and a moving portion 106 that moves relative to the fixed portion 104 along a translation axis 122. However, in assembly 800, the fixed portion 104 includes a single coil 808, and the moving portion 106 includes a single first magnet member 812, a single second magnet member 814, and a third magnet member 830 coupled to the first magnet member 812, which are connected to each other (and the actuation surface) and all move relative to the coil 808. The first magnet member 812 can be a radially polarized magnet positioned radially outward from the coil 808, and the second magnet member 814 is positioned radially inward from the coil 808. The second magnet member 814 can be a flux concentrating member (e.g., a steel structure) that concentrates the magnetic flux lines 824 generated by the first magnet member 812 into an area of ​​concentrated or focused magnetic flux density 826. The third magnetic member 830 can be a flux concentrating member directly attached to the surface of the first magnetic member 812 facing the coil 808. Typically, the third magnetic member 830 can be a soft magnetic material, such as steel, similar to the second magnetic member 814, and attached to the surface of the first magnetic member 812. For example, the third magnetic member 830 can be attached to the inner surface of the first magnetic member 812 facing the coil 808. In this regard, when the first magnetic member 812 and the second magnetic member 814, to which the third magnetic member 830 is attached, translate together along the coil 808 positioned within the gap 816 formed by the magnetic members, the focused magnetic flux density region 826 also travels along the winding height of the coil 808. Thus, as previously described, the primary magnetic flux density region can be maintained along the entire height of the coil 808, thereby enabling a greater deflection of the actuating surface (e.g., actuating surface 118) connected to the moving portion 106.

[0047] Now see Figure 9 , Figure 9An assembly 900 is shown that is similar to the previously discussed assemblies in that it includes a fixed portion 104 and a moving portion 106 that moves relative to the fixed portion 104 along a translation axis 122. However, in assembly 900, the fixed portion 104 includes a pair of coils 908A and 908B, and the moving portion 106 includes a pair of first magnet members 912A, 912B, a single second magnet member 914, and four third magnet members 930A, 930B, 930C, and 930D ​​coupled to each of the inner and outer surfaces of the first magnet members 912A-B, all of which move relative to the coils 908A, 908B. The first magnet members 912A-B can be radially polarized magnets, as shown, positioned radially outward and radially inward of the pair of coils 908A-B, and the second magnet member 914 is positioned between the coils 908A-B. The second magnet member 914 can be a flux concentrating member (e.g., a steel structure) that concentrates the magnetic flux lines 924 generated by the first magnet members 912A-B into an area of ​​concentrated or focused magnetic flux density 926. The third magnet members 930A-D can be flux concentrating members that are directly attached to the surface of the first magnet members 912A-B. Representatively, the third magnet members 930A-D can be a soft magnetic material similar to the second magnet member 914, such as a steel material, and attached to the surface of the first magnet members 912A-B. For example, third magnet member 930A can be attached to the inner surface of first magnet member 912A facing the center of the assembly, third magnet member 912B can be attached to the outer surface of first magnet member 912A facing coil 908A, third magnet member 930C can be attached to the inner surface of first magnet member 912B facing coil 908B, and third magnet member 930D ​​can be attached to the outer surface of first magnet member 912B facing away from coil 908B. In this regard, when first magnet member 912A-B and second magnet member 914, with third magnet members 930A-D attached, translate together along coil 908A-B positioned within gap 916A, 916B formed by the magnet members, the focused magnetic flux density region 926 also travels along the winding height of coil 908A-B. Thus, as previously described, a primary magnetic flux density region may be maintained along the entire height of the coils 908A-B, thereby enabling greater excursion of an actuation surface (eg, actuation surface 118 ) coupled to the moving portion 106 .

[0048] Now see Figure 10 , Figure 10An assembly 1000 is shown that is similar to the previously discussed assemblies in that it includes a fixed portion 104 and a moving portion 106 that moves relative to the fixed portion 104 along a translation axis 122. However, in assembly 1000, the fixed portion 104 includes a single coil 1008, and the moving portion 106 includes a single first magnet member 1012, a single second magnet member 1014, and a pair of third magnet members 1030A, 1030B coupled to the first magnet member 1012, which are attached to each other (and the actuation surface) and all move relative to the coil 1008. The first magnet member 1012 can be a radially polarized magnet positioned radially outward from the coil 1008, and the second magnet member 1014 is positioned radially inward from the coil 1008. The second magnet member 1014 can be a flux concentrating member (e.g., a steel structure) that concentrates the magnetic flux lines 1024 generated by the first magnet member 1012 into an area of ​​concentrated or focused magnetic flux density 1026. The third magnet members 1030A-B can be flux concentrating members that are directly attached to the inner and outer surfaces of the first magnet member 1012. Typically, the third magnet members 1030A-B can be a soft magnetic material, such as steel, similar to the second magnet member 1014, and attached to the surface of the first magnet member 1012. For example, the third magnet member 1030A can be attached to the inner surface of the first magnet member 1012 facing the coil 1008, and the third magnet member 1030B can be attached to the outer surface of the first magnet member 1012 facing away from the coil 1008. In this regard, when the first magnet member 1012 and the second magnet member 1014, with the third magnet members 1030A-B attached, translate together along the coil 1008 positioned within the gap 1016 formed by the magnet members, the focused magnetic flux density region 1026 also travels along the winding height of the coil 1008. Thus, as previously described, a primary magnetic flux density region may be maintained along the entire height of the coil 1008, thereby enabling greater excursion of an actuation surface (eg, actuation surface 118) coupled to the moving portion 106.

[0049] Now see Figure 11 , Figure 11An assembly 1100 is shown that is similar to the previously discussed assemblies in that it includes a fixed portion 104 and a moving portion 106 that moves relative to the fixed portion 104 along a translation axis 122. However, in assembly 1100, the fixed portion 104 includes a single coil 1108, and the moving portion 106 includes a pair of first magnet members 1112A, 112B and a pair of third magnet members 1130A, 1130B coupled to the first magnet members 1112A-B, all of which move relative to the coil 1108. Thus, the moving portion 106 in this aspect omits the previously discussed second magnet member (e.g., magnet member 1014). The first magnet member 1112A can be a radially polarized magnet positioned radially inward of the coil 1108, and the first magnet member 1112B is positioned radially outward of the coil 1108. The third magnet members 1130A-B can be flux concentrating members (e.g., steel structures) attached to the surface of the first magnet members 1112A-B facing the coil 1108. The third magnet members 1130A-B can be flux concentrating members that concentrate the magnetic flux lines 1124 generated by the first magnet members 1112A-B into an area of ​​concentrated or focused magnetic flux density 1126. The third magnet members 1130A-B can be directly attached to the surface of the first magnet members 1112A-B facing the coil 1108. Representatively, the third magnet member 1130A can be a soft magnetic material, such as steel, attached to the outer surface of the first magnet member 1112A, and the third magnet member 1130B can be a soft magnetic material, such as steel, attached to the inner surface of the first magnet member 1112B. In this regard, as the first magnet assembly 1112A-B with the attached third magnet assembly 1130A-B translates together along the coil 1108, which is positioned within the gap 1116 formed by the magnet assembly, the region of focused magnetic flux density 1126 also travels along the height of the windings of the coil 1108. Thus, as previously described, the primary region of magnetic flux density can be maintained along the entire height of the coil 1108, thereby enabling greater excursion of an actuating surface (e.g., actuating surface 118) coupled to the moving portion 106.

[0050] Figure 12 A simplified schematic perspective view of an exemplary electronic device in which a transducer assembly as described herein may be implemented is shown. Figure 12As shown, the transducer assembly can be integrated into a consumer electronic device 1202, such as a smartphone, where a user can make a call with a remote user of a communication device 1204 via a wireless communication network; in another example, the transducer assembly can be integrated into the housing of a tablet computer 1206. These are just two examples of where the transducer assembly described herein can be used; however, it is contemplated that the transducer assembly can be used with any type of electronic device, such as a home audio system, any consumer electronic device with audio capabilities, or an audio system in a vehicle (e.g., a car infotainment system).

[0051] Figure 13 A block diagram of some components of an electronic device in which a transducer assembly as disclosed herein may be implemented is shown. Device 1300 may be any of several different types of consumer electronic devices, such as those described in connection with FIG. Figure 12 Any of those consumer electronic devices discussed.

[0052] In this regard, electronic device 1300 includes a processor 1312 that interacts with camera circuitry 1306, motion sensor 1304, storage 1308, memory 1314, display 1322, and user input interface 1324. Main processor 1312 may also interact with communication circuitry 1302, main power supply 1310, transducer 1318, and microphone 1320. Transducer 1318 may be a speaker and / or transducer assembly as described herein. The various components of electronic device 1300 may be digitally interconnected and used or managed by a software stack being executed by processor 1312. Many of the components shown or described herein may be implemented as one or more dedicated hardware units and / or programmed processors (software being executed by a processor, such as processor 1312).

[0053] Processor 1312 controls the overall operation of device 1300 by executing some or all of the operations of one or more application programs or operating system programs implemented on device 1300, and by executing instructions (software code and data) that may be found in storage device 1308. Processor 1312 may, for example, drive display 1322 and receive user input through user input interface 1324 (which may be integrated with display 1322 as part of a single touch-sensitive display panel). In addition, processor 1312 may send current or signals (e.g., audio signals) to transducer 1318 to facilitate operation of transducer 1318. Typically, processor 1312 may send current or signals to one or more components of a transducer assembly (e.g., assemblies 100 to 1100) to drive these components independently or collectively. For example, coils 108 to 1108 may be driven independently by different channels on an amplifier, or driven collectively by the same channel, depending on the application.

[0054] Storage 1308 provides relatively large amounts of "persistent" data storage using non-volatile solid-state memory (e.g., flash memory storage) and / or dynamic non-volatile storage devices (e.g., rotating disk drives). Storage 1308 may include both local storage space and storage space on remote servers. Storage 1308 may store data as well as software components that control and manage the various functions of device 1300 at a higher level.

[0055] In addition to storage 1308, there may also be memory 1314, also referred to as main memory or program memory, which provides relatively fast access to stored code and data being executed by processor 1312. Memory 1314 may include solid-state random access memory (RAM), such as static RAM or dynamic RAM. There may be one or more processors, such as processor 1312, that run or execute various software programs, modules, or instruction sets (e.g., application programs) that, while permanently stored in storage 1308, have been transferred to memory 1314 for execution to perform the various functions described above.

[0056] Device 1300 may include communication circuitry 1302. Communication circuitry 1302 may include components for wired or wireless communication, such as two-way conversation and data transmission. For example, communication circuitry 1302 may include RF communication circuitry coupled to an antenna, enabling a user of device 1300 to place or receive calls over a wireless communication network. RF communication circuitry may include an RF transceiver and a cellular baseband processor to enable calls over a cellular network. For example, communication circuitry 1302 may include Wi-Fi communication circuitry, enabling a user of device 1300 to place or initiate calls using a Voice over Internet Protocol (VOIP) connection to transmit data over a wireless local area network.

[0057] The device may include a transducer 1318. The transducer 1318 may be a speaker and / or a transducer assembly, such as a reference Figures 1 to 12 The transducer assembly described herein. The transducer 1318 can be an electroacoustic transducer or sensor that converts an electrical signal input (e.g., an acoustic input) into an acoustic or vibration output. The speaker circuitry can be electrically connected to the processor 1312 and the power supply 1310 to facilitate speaker operation (e.g., diaphragm displacement, etc.) as previously discussed.

[0058] The device 1300 may also include a motion sensor 1304, also known as an inertial sensor, which may be used to detect movement of the device 1300, a camera circuit 1306 that implements the digital camera functionality of the device 1300, and a main power source 1310, such as a built-in battery serving as the main power source.

[0059] Although certain aspects have been described and illustrated in the accompanying drawings, it should be understood that such aspects are merely illustrative of the broad disclosure and not restrictive, and that the disclosure is not limited to the specific constructions and arrangements shown and described, as various other modifications may occur to those skilled in the art. Accordingly, the description is to be regarded as illustrative and not restrictive. Furthermore, to assist the Patent Office and any reader of any patent issued in this application in interpreting the appended claims, applicants wish to note that they do not intend for any appended claim or claim element to invoke 35 U.S.C. §112(f) unless the phrase "means for" or "step for" is explicitly used in a particular claim.

Claims

1. A moving magnet motor, comprising: a stationary coil coupled to the frame; a moving magnet assembly movably coupled to the frame and operable to move relative to the stationary coil, the moving magnet assembly including a magnet and a flux concentrating member defining a gap in which the stationary coil is positioned and a region of dominant magnetic flux density along the entire winding height of the stationary coil; and An actuation surface is coupled to the moving magnet assembly, and wherein movement of the moving magnet assembly drives movement of the actuation surface along a translation axis. 2 . The moving magnet motor of claim 1 , wherein the stationary coil is a continuous voice coil. 3 . The moving magnet motor of claim 1 , wherein the fixed coil is an annular voice coil, the magnet is radially inside the voice coil, and the flux concentrating member is radially outside the voice coil. 4 . The moving magnet motor of claim 1 , wherein the fixed coil is an annular voice coil, the flux concentrating member is radially inside the voice coil, and the magnet is radially outside the voice coil. The moving magnet electric machine of claim 1 , wherein the magnets are radially polarized magnets. The moving magnet electric machine of claim 1 , wherein the flux concentrating member is a steel structure.

7. The moving magnet electric machine of claim 1, wherein the flux concentrating members are radially polarized magnets.

8. The moving magnet electric machine of claim 1, wherein the flux concentrating member is a first flux concentrating member and the moving magnet assembly further comprises a second flux concentrating member directly coupled to the magnets. 9 . The moving magnet motor assembly of claim 1 , wherein the stationary coil is a first stationary voice coil, the assembly further comprising a second stationary voice coil positioned radially outward of the first stationary voice coil. 10 . The moving magnet motor assembly of claim 9 , wherein the first stationary voice coil and the second stationary voice coil have the same current direction and the same orientation.

11. The moving magnet motor of claim 9 , wherein the flux concentrating member is positioned between the first and second stationary voice coils, and the magnet is a first radially polarized magnet, the moving magnet assembly further comprising a second radially polarized magnet, and wherein the first radially polarized magnet is positioned radially inward of the first stationary voice coil, and the second radially polarized magnet is positioned radially outward of the second stationary voice coil.

12. The moving magnet motor of claim 9, wherein the magnet is positioned between the first and second stationary voice coils, the flux concentrating member is a first flux concentrating member, the moving magnet assembly further comprises a second flux concentrating member, and wherein the first flux concentrating member is positioned radially inward of the first stationary voice coil, and the second flux concentrating member is positioned radially outward of the second stationary voice coil.

13. A moving magnet motor assembly for a loudspeaker, comprising: a fixed portion comprising a continuous voice coil fixedly coupled to the frame; and a moving portion comprising a diaphragm and a magnet assembly movably coupled to the frame, the magnet assembly having a first magnet member and a second magnet member, the first magnet member and the second magnet member being operable to focus magnetic flux density toward the continuous voice coil and to translate along the continuous voice coil to drive the diaphragm to move along a translation axis, wherein the magnet assembly has a displacement range along the translation axis, the displacement range being defined by the height of the continuous voice coil.

14. The loudspeaker moving magnet motor assembly of claim 13, wherein the first magnet member is a radially polarized magnet and the second magnet member is a steel member positioned on opposite sides of the continuous voice coil.

15. The loudspeaker moving magnet motor assembly of claim 13, wherein the first magnet member and the second magnet member define a gap, the continuous voice coil being positioned within the gap. 16 . The loudspeaker moving magnet motor assembly of claim 13 , wherein the moving portion further comprises a third magnet member directly attached to the first magnet member or the second magnet member.

17. The loudspeaker moving magnet motor assembly of claim 13, wherein the continuous voice coil is a first continuous voice coil and the fixed portion further comprises a second continuous voice coil.

18. The loudspeaker moving magnet motor assembly of claim 17 , wherein the second magnet member is a steel structure positioned between the first and second continuous voice coils, the moving portion further comprising a third magnet member, and wherein the first and third magnet members are positioned along opposite sides of the first and second continuous voice coils from the second magnet member.

19. The loudspeaker moving magnet motor assembly of claim 17, wherein the moving portion further comprises a third magnet, and the first, second, and third magnet members are radially polarized magnets positioned along different sides of the first and second continuous voice coils.

20. The loudspeaker moving magnet motor assembly of claim 17, wherein the first magnet member is a radially polarized magnet positioned between the first continuous voice coil and the second continuous voice coil, the moving portion further comprises a third magnet member, and wherein the second magnet member and the third magnet member are steel structures positioned along different sides of the first continuous voice coil and the second continuous voice coil.

21. An electronic device, comprising: Electronic equipment housing: a moving magnet motor coupled to the electronics housing, the moving magnet motor having a stationary coil and a moving magnet assembly operable to move relative to the stationary coil, the moving magnet assembly including magnets and a flux concentrating member defining a gap in which the stationary coil is positioned and having a range of displacement along an entire winding height of the stationary coil; and An actuating surface is coupled to the moving magnet assembly, wherein movement of the moving magnet assembly drives movement of the actuating surface along a translation axis.

22. The electronic device of claim 21, wherein the moving magnet motor is a speaker moving magnet motor and the actuating surface is a speaker diaphragm.

23. The electronic device of claim 21, wherein the actuation surface is a housing wall of the electronic device housing.

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