Moving magnet type motor

Abstract

The invention relates to a moving magnet type motor. The present invention provides a moving magnet type motor comprising: 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 actuation surface coupled to the moving magnet assembly, and wherein movement of the moving magnet assembly drives movement of the actuation surface along a translating axis.

Description

[0001] This application is a divisional application of Chinese Patent Application No. 202210384834.1, filed on April 13, 2022, entitled “Moving Magnet Motor”.

[0002] Cross Reference to Related Applications

[0003] This application is a non-provisional of co-pending U.S. Provisional Patent Application No. 63 / 174,942, filed April 14, 2021, and incorporated herein by reference. TECHNICAL FIELD

[0004] One aspect of the present disclosure relates to a moving magnet motor including a moving magnet motor having a magnet assembly that moves relative to a coil to focus a magnetic field above the coil and reduce a back field effect. Other aspects are also described and claimed. BACKGROUND

[0005] In modern consumer electronics, audio functionality is playing an increasingly larger role as digital audio signal processing and audio content delivery continue to improve. In this regard, a wide range of consumer electronics devices can benefit from improvements in audio performance. For example, portable devices that use electrodynamic transducers with moving motor systems can benefit from improved performance. For example, while moving motor systems can have the advantage of using larger coils than non-moving motor systems, their efficiency can be lower because they use open magnetic circuits around magnets that do not have a focused magnetic field region. This in turn causes back flux to pass through the same coil that is producing Lorentz forces to excite the diaphragm. At large excursions, there is no dominant flux density over the coil, which will introduce distortion because the positive and negative Lorentz forces almost cancel each other out. SUMMARY

[0006] One aspect of the present disclosure relates to improvements to moving magnet motors, such as speaker motors. Typically, moving magnet speakers are designed to use the stray magnetic flux density of the magnets that are not part of a closed magnetic circuit to move the motor. When the magnets are used outside of the magnetic circuit, their ability to focus the magnetic flux density is very poor. The working point of the magnets in free space is very low, so the magnets cannot be saved from demagnetization at high temperatures as well. Therefore, when a speaker is manufactured with moving magnets that do not use any magnetic flux guiding elements, back flux also passes through the same coil that is producing Lorentz forces to excite the diaphragm. At large excursions, there is no dominant flux density over the coil, which will introduce distortion because the positive and negative Lorentz forces almost cancel each other out.

[0007] Accordingly, the present disclosure provides a moving magnet motor having a closed magnetic circuit configured to focus the magnetic flux density on the coil and travel above the coil that drives the movement of the actuation surface (e.g., a speaker diaphragm). This configuration results in a very small back magnetic field compared to the main flux density on the coil, so that a large excursion and low distortion value can be achieved. To achieve this, one or more radially polarized magnets are positioned close to the voice coil (e.g., an inner coil and an outer coil having the same winding height), and the magnetic lines of the magnets are concentrated to one or more flux concentration members made of soft magnetic material (e.g., steel material) 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. This moving mass in turn is connected to the actuation surface (e.g., a speaker diaphragm), so that its movement drives the movement (e.g., vibration) of the actuation surface. Since the highest concentration of flux density occurs between the soft magnetic material and the magnets, the main magnetic flux density moves with the moving assembly without being greatly reduced by the position of the diaphragm. This area of main flux density that moves on the voice coil gives the actuation surface (e.g., the diaphragm) a greater excursion without observing the back magnetic field interference. This is because the magnitude of the back magnetic field becomes very small compared to the main magnetic flux density between the hard and soft magnetic components. Accordingly, a moving magnet motor system for driving an actuation surface with a large excursion and a low distortion value can be achieved.

[0008] Representatively, in one aspect, a moving magnet motor including 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 voice coil, the moving magnet assembly including a magnet and a flux concentration member, the magnet and the flux concentration member defining a gap, the stationary voice coil positioned within the gap; and an actuation surface coupled to the moving magnet assembly, and wherein movement of the moving magnet assembly drives movement of the actuation surface along a translational axis. The stationary voice coil can be a continuous voice coil. The stationary voice coil can be a ring voice coil and the magnet is radially inward of the voice coil and the flux concentration member is radially outward of the voice coil. In other aspects, the flux concentration member can be radially inward of the voice coil and the magnet is radially outward of the voice coil. The magnet can be a radially polarized magnet. The flux concentration member can be a steel structure. In other aspects, the flux concentration member can be a radially polarized magnet. In some aspects, the flux concentration member is a first flux concentration member and the moving magnet assembly further includes a second flux concentration member directly coupled to the magnet. In further aspects, the stationary voice 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 stationary voice coil and the second stationary voice coil have the same current direction and the same orientation. In some aspects, the flux concentration member is positioned between the first stationary voice coil and the second stationary voice coil and the magnet is a first radially polarized magnet, the moving magnet assembly further including 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. In other aspects, the magnet is positioned between the first stationary voice coil and the second stationary voice coil, the flux concentration member is a first flux concentration member, the moving magnet assembly further includes a second flux concentration member, and wherein the first flux concentration member is positioned radially inward of the first stationary voice coil and the second flux concentration member is positioned radially outward of the second stationary voice coil.

[0009] In another aspect, a speaker magnet motor assembly includes a fixed portion including a continuous voice coil fixedly coupled to a frame; and a moving portion is provided including 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 a magnetic flux density toward the continuous voice coil and translate along the continuous voice coil to drive the diaphragm to move along a translation axis. The magnet assembly can have a range of displacement along the translation axis defined by a 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 magnetic members define a gap in which the continuous voice coil is located. In some aspects, the moving portion further includes a third magnet member directly attached to the first or second magnet member. In further 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 including a third magnet member, where 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 include a third magnet member and the first, second, and third magnet members are radially polarized magnets positioned along different sides of the first and second continuous voice coils. In further aspects, the first magnet member is a radially polarized magnet positioned between the first and second continuous voice coils, the moving portion further including a third magnet member, and where the second and third magnet members are steel structures positioned along different sides of the first and second continuous voice coils.

[0010] 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 can include a stationary voice coil and a moving magnet assembly operable to move relative to the stationary coil. The moving magnet assembly can include a magnet and a flux concentration member defining a gap in 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.

[0011] In some aspects, any of the foregoing configurations of moving magnet motors can be a speaker moving magnet motor or a shaker integrated within a portable electronic device.

[0012] The above overview does not include an exhaustive list of all aspects of this disclosure. It is contemplated that the invention encompasses all systems and methods that can be implemented by all suitable combinations of the aspects outlined above and the various aspects disclosed in the detailed embodiments below and specifically pointed out in the claims filed with this patent application. Such combinations have specific advantages not specifically described in the above overview. Attached Figure Description

[0013] Several aspects are illustrated in the accompanying drawings by way of example rather than limitation, and similar reference numerals in the drawings indicate similar elements. It should be noted that references to “a” or “an” aspect in this disclosure do not necessarily refer to the same aspect, and that they mean at least one.

[0014] Figure 1 A cross-sectional side view of one aspect of a moving magnet type motor assembly is shown.

[0015] Figure 2 A schematic cross-sectional side view of another aspect of the moving magnet type motor assembly is shown.

[0016] Figure 3 A schematic cross-sectional side view of another aspect of the moving magnet type motor assembly is shown.

[0017] Figure 4 A schematic cross-sectional side view of another aspect of the moving magnet type motor assembly is shown.

[0018] Figure 5 A schematic cross-sectional side view of another aspect of the moving magnet type motor assembly is shown.

[0019] Figure 6 A schematic cross-sectional side view of another aspect of the moving magnet type motor assembly is shown.

[0020] Figure 7 A schematic cross-sectional side view of another aspect of the moving magnet type motor assembly is shown.

[0021] Figure 8 A schematic cross-sectional side view of another aspect of the moving magnet type motor assembly is shown.

[0022] Figure 9 A schematic cross-sectional side view of another aspect of the moving magnet type motor assembly is shown.

[0023] Figure 10 A schematic cross-sectional side view of another aspect of the moving magnet type motor assembly is shown.

[0024] Figure 11 A schematic cross-sectional side view of another aspect of the moving magnet type motor assembly is shown.

[0025] Figure 12 A simplified schematic of an electronic device in which a transducer assembly can be implemented is shown.

[0026] Figure 13 A block diagram of some of the constituent components of an electronic device in which a transducer assembly can be implemented is shown. DETAILED DESCRIPTION

[0027] In this section, we will explain several preferred aspects of the present disclosure with reference to the accompanying drawings. As long as the shape, relative position, and other aspects of the components described in these aspects are not explicitly limited, the scope of the present disclosure is not limited only to the components shown, which are for illustrative purposes only. In addition, although many details are set forth, it is to be understood that some aspects of the present disclosure can be practiced without these details. In other instances, well-known structures and techniques have not been shown in detail so as not to obscure the understanding of this description.

[0028] The terminology used herein is for the purpose of describing particular aspects only and is not intended to be limiting of the present disclosure. Spatially relative terms, such as "below", "beneath", "lower", "above", "upper", and the like, can be used herein for ease of description to describe one element's or feature's relationship to another element(s) or feature(s) as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientations depicted in the figures. For example, if a device is inverted in the figure, a lower surface can then be oriented upward - i.e., it can be oriented "above" other elements or features. Thus, the exemplary term "below" can encompass both an orientation of above and below. The device can be otherwise oriented (e.g., rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

[0029] As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises", "comprising", "includes" and / or "including" when used herein, 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.

[0030] The terms "or" and "and / or," as used herein, are to be interpreted as inclusive or meaning any one or any combination. Therefore, "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 will occur only when a combination of elements, functions, steps or acts are in some way inherently mutually exclusive.

[0031] Figure 1 A cross-sectional view of a moving magnet motor assembly is shown. In one aspect, for example, the assembly 100 can be a moving magnet motor integrated within an electrodynamic or electroacoustic transducer that converts an electrical signal into a vibration and / or sound signal that can be output from a device in which the assembly 100 is integrated. For example, the assembly 100 can be a loudspeaker moving magnet motor. In another aspect, the assembly 100 can be a shaker for actuating or vibrating any type of surface or structure coupled thereto to provide, for example, a haptic output. For example, the assembly 100 can be a loudspeaker and / or shaker integrated within a smartphone or other similar portable electronic device. In some cases, the assembly 100 can be attached to a surface of a device to actuate (e.g., vibrate) the surface. The assembly 100 can be encapsulated within and integrated within a housing or casing of the device.

[0032] The assembly 100 can generally include a frame 102, a stationary portion 104, and a moving portion 106 that moves relative to the stationary portion 104 and the frame 102. The frame 102 can be any type of support structure that can support components of the assembly and for integrating the assembly within a surrounding device (e.g., a portable electronic device). In some aspects, the frame 102 can be part of a housing of a device in which the assembly 100 is integrated. In one aspect, the stationary portion 104 can include one or more coils 108 fixedly connected to the frame 102. The one or more coils 108 can be, for example, voice coils formed from a copper wire winding. The voice coil 108 can be mounted to a bottom wall or side 110 of the frame 102 at one end. In this aspect, the voice coil can have a winding height that extends vertically or parallel to a z-height of the assembly 100, as shown. The other end (e.g., top end) of the coil 108 can be free and not directly attached to any other structure or component of the assembly 100. During operation, the coil 108 can be powered by an electrical current in a desired direction and used to drive movement of the moving portion 106.

[0033] The moving portion 106 can include a first magnet member 112 and a second magnet member 114 that together define a gap 116 within which the coil 108 is positioned. The first magnet member 112 and the second magnet member 114 can form a closed magnetic circuit that focuses magnetic flux density toward the coil 108. In this regard, upon application of current 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 arrow. The translation axis 122 may, for example, be parallel to a z-axis of the assembly 100. In some aspects, the translation axis 122 can be considered to extend in an axial direction and can define a symmetry axis of the assembly 100. In further aspects, the translation axis 122 can be considered to extend parallel to or in a direction that is the same as a winding height of the coil 108 or a height of the gap 116 defined by the first magnet member 112 and the second magnet member 114. The first magnet member 112 and the second magnet member 114 are in turn connected to an actuation surface 118 that is coupled to the frame 102 by a suspension member 120. Since the first magnet 112 and the second magnet 114 are part of the same moving mass, the first magnet 112 and the second magnet 114 move together and drive the actuation surface 118 to move along the translation axis 122. Since the highest concentration of magnetic flux density occurs between the first magnet member 112 and the second magnet member 114, the primary magnetic flux density moves with the moving mass without being greatly reduced as a function of the position of the actuation surface 118 to which it is coupled. This primary flux density region that moves above the coil 108 allows for greater excursion of the actuation surface 118 (e.g., diaphragm) without observing the back EMF interference as described previously. Thus, the assembly 100 implements a moving magnet motor system that drives an actuation surface with large excursion and low distortion values.

[0034] Referring now in more detail to the first magnet member 112 and the second magnet member 114, in some aspects, at least one of the first magnet member 112 and / or the second magnet member 114 can be a polarized magnet. The polarized magnet can be a radial polarized magnet that is oriented within the assembly such that the north and south poles are arranged radially with respect to the translation axis 122. In other words, as Figure 1As shown, the first magnet member 112 or the second magnet member 114 can be oriented to the left or to the right. In further aspects, one of the first magnet member 112 or the second magnet member 114 can be a flux concentrating member or structure operable to focus the magnetic flux lines of the polarized magnet (e.g., magnet member 112 or 114). Typically, one of the first magnet member 112 or the second magnet member 114 can be a soft magnetic material, such as a steel material operable 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 with the first magnet member 112 along the coil 108 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 further 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. In all cases, however, 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 (e.g., a radially polarized magnet or a soft magnetic material such as steel) that can concentrate the magnetic flux lines toward the coil 108.

[0035] 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 by the moving members 112, 114 and outputs sound. In other aspects, the actuation surface 118 can be any type of surface that needs to be moved or vibrated. For example, in other aspects, the actuation surface 118 can be a wall of a housing or enclosure, such as a housing of a device in which the assembly 100 is integrated, or another surface or structure that can be used to create, for example, a haptic output that is 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 by a connecting member 122 (e.g., a bracket, fastener, etc.) and the actuation surface 118 and / or the suspension member 120 can be connected to the first member 112 or the second member 114 by another connecting member 124 (e.g., a bracket, fastener, etc.).

[0036] Further, while 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 are contemplated. 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. Further, it is contemplated 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, elliptical, or racetrack shape. In this regard, the first magnet member 112 can be considered an inner magnet member 112 that is surrounded by the coil 108, and the second magnet member 114 can be considered an outer magnet member that surrounds the coil 108. In other words, the first magnet member 112 can be considered radially inward of the coil 108, the coil 108 can be radially inward of the second magnet member 114, and the second magnet member 114 can be radially outward of the coil 108.

[0037] Reference will now be made to Figures 2 to 11 Various magnet member / coil configurations for the assembly 100 will now be described in greater detail. Figures 2 to 11 Cross-sectional side views of the right-hand side of various assembly configurations are shown. It will be appreciated that the assemblies are symmetrical, and thus the left-hand side (not shown) will be a mirror image of the right-hand side shown in Figures 2 to 11 For example, the translation axis 122 shown in each of the figures can be considered a symmetry axis about which the assembly is considered symmetrical. Additionally, it is noted that aspects of the frame, actuation surfaces, etc. are omitted in Figures 2 to 11 for ease of illustration. However, the omitted aspects are to be understood as included in the complete assembly of Figures 2 to 11 as previously discussed with reference to Figure 1

[0038] Reference will now be made to Figure 2 , Figure 2 ​An assembly 200 is shown having a fixed portion 104 including a pair of coils 208A, 208B and a moving portion 106 including a pair of first magnet members 212A, 212B and a second magnet member 214. As previously described, the moving portion 106 (e.g., first magnet members 212A-B and second magnet member 214) moves relative to the fixed portion 104 (e.g., coils 208A-B). In particular, each of the first magnet members 212A-B and the second magnet member 214 translate together relative to the coils 208A-B along the axis of translation 122 as shown by the arrows. Both of the first magnet members 212A-B can be radially polarized magnets with their magnetic poles oriented in the same direction as 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 produced by the first magnet members 212A-B into a region of focused magnetic flux density 226. In this regard, as the first magnet members 212A-B and the second magnet member 214 translate together along the coils 208A-B, these coils are positioned within the gap 216A, 216B formed by the magnet members, and the region of focused flux density 226 also travels along the winding height of the coils 208A-B. Thus, a region of primary magnetic flux density can be maintained along the entire height of the coils 208A-B. This in turn enables a greater excursion of an actuation surface (e.g., actuation surface 118) connected to the moving portion 106 without observing reverse magnetic field interference.

[0039] Referring now in more detail to the pair of coils 208A-B, the coils 208A-B can be individual voice coils in some aspects, each having a winding height that extends parallel to the z-axis or along the z-height direction shown. The coils 208A-B can be in series or parallel with the same current direction depending on requirements from, for example, an associated loudspeaker, and thus they are constructive. The two coils 208A-B should have the same orientation (e.g., both coils into the plane, or both coils out of the plane). The coils 208A-B can have the same winding height as shown, which in some cases can be greater than the height of the magnet members of the moving portion 106 and the gap 216A-B as shown. In other aspects, the coils 208A-B can have different winding heights. However, each of the coils 208A-B can be considered a continuous coil in that they have one continuous and uninterrupted winding height, in some cases formed by a single length of copper wire. In other words, the coils 208A-B are not formed by one coil portion or segment stacked on top of another to achieve the desired overall height shown in the figures. Further, as previously mentioned, in some aspects the coils 208A-B are toroidal coils, and thus the coil 208A can be considered an inner coil and the coil 208B can be considered an outer coil. Said another way, the coil 208A can be considered radially inward of the coil 208B, or the coil 208B can be considered radially outward of the coil 208A.

[0040] Similarly, the magnet members 212A-B and 214 of the moving portion 106 can be toroidal members (e.g., circular, elliptical, racetrack-shaped, etc.). In this aspect, the first magnet members 212A-B can be considered inner and outer magnet members, respectively, and the second magnet member 214 can be an intermediate magnet member between the inner and outer magnet members 212A-B. Still further, the coil gap 216A can be considered an inner gap formed between the inner magnet member 212A and the intermediate magnet member 214, and the coil gap 216B can be considered an outer gap formed between the intermediate magnet member 214 and the outer magnet member 212B.

[0041] As previously mentioned, both first magnet members 212A and 212B can be radially polarized magnets, and second magnet member 214 can be a flux concentration 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 the translation axis 222, which corresponds to the axis of symmetry. Regardless of the heights 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 over a certain region of the magnet assembly, such that when it moves along coils 208A-B, it is not affected by the counter magnetic field (which is weaker than the focused positive magnetic field), and therefore, the sum of the magnetic fields is not affected, and thus the force from the circuitry is not affected. Thus, since the moving part 106 carries the positive magnetic field along the entire height of coils 208A-B, which exceeds the counter magnetic field, a positive force appears along the entire height of the coils, allowing an improved displacement range to be obtained. This forms a contrast to an open circuit system that does not have a focused magnetic flux region and does not move along the coils, and can therefore lose force along certain regions of the coils.

[0042] Referring now to Figure 3 , Figure 3 An assembly 300 is shown that is similar to the previously discussed assemblies in that it includes a stationary portion 104 and a moving portion 106 that moves relative to stationary portion 104 along a translation axis 122. However, in assembly 300, stationary portion 104 includes a single coil 308, and 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 coil 308. First magnet member 312 can be a radially polarized magnet that is positioned radially outward of coil 308. Second magnet member 314 can be a flux concentration member, such as a steel structure, that is positioned radially inward of coil 308. As previously mentioned, second magnet member 314 concentrates the magnetic flux lines 324 produced by first magnet member 312 within a region of concentrated or focused magnetic flux density 326. In this aspect, when first magnet member 312 and second magnet member 314 are translated along coil 308, which is positioned within a gap 316 formed by the magnet members, the region of focused flux density 326 also travels along the winding height of coil 308. Thus, as previously mentioned, a region of primary magnetic flux density can be maintained along the entire height of coil 308, which in turn can enable a greater excursion of an actuation surface (e.g., actuation surface 118) connected to moving portion 106.

[0043] Referring now to Figure 4 , Figure 4An assembly 400 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 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 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, e.g., radially inside of coil 408A and radially outside of coil 408B. As previously discussed, the second magnet members 414A-B concentrate the magnetic flux lines 424 produced by the first magnet member 412 within a region of concentrated or focused magnetic flux density 426. In this regard, as the first magnet member 412 and the second magnet members 414A-B are translated together along the coils 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 coils 408A-B. Thus, as previously discussed, a primary magnetic flux density region can be maintained along the entire height of the coils 408A-B, which in turn can enable greater deflection of an actuation surface (e.g., actuation surface 118) connected to the moving portion 106.

[0044] Referring now to Figure 5 , Figure 5A component 500 is shown that is similar to the previously discussed components 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 the component 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 to an 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 concentration member, such as a steel structure, positioned radially outward of the coil 508. As previously discussed, the second magnet member 514 concentrates the magnetic flux lines 524 produced by the first magnet member 512 within a region of concentrated or focused magnetic flux density 526. In this regard, as the first and second magnet members 512, 514 are translated 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 discussed, a primary magnetic flux density region can be maintained along the entire height of the coil 508, which in turn can enable a greater excursion of an actuation surface (e.g., the actuation surface 118) connected to the moving portion 106.

[0045] Referring now to Figure 6 , Figure 6 A component 600 is shown that is similar to the previously discussed components 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 the component 600, the fixed portion 104 includes a pair of coils 608A and 608B and the moving portion 106 includes three first magnet members 612A, 612B, and 612C that are attached together (as well as an actuation surface) and move relative to the coils 608A, 608B. The first magnet members 612A-C can be radially polarized magnets positioned between and outside of the pair of coils 608A-B in the same direction (e.g., north and south poles facing the same direction). In this regard, the first magnet members 612A-C act as flux concentration members for one another and concentrate the magnetic flux lines 624 produced by the first magnet members 612 within a region of concentrated or focused magnetic flux density 626. In this regard, as the first magnet members 612A-C are translated together along the coils 608A-B positioned within the gaps 616A, 616B formed by the magnet members, the region of focused magnetic flux density 626 also travels along the winding height of the coils 608A-B. Thus, as previously discussed, a primary magnetic flux density region can be maintained along the entire height of the coils 608A-B, which in turn can enable a greater excursion of an actuation surface (e.g., the actuation surface 118) connected to the moving portion 106.

[0046] Referring now to 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 the 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 that are connected together (and 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 magnet member 714 can be a flux concentrating member (e.g., a steel structure) that concentrates the magnetic flux lines 724 produced by the first magnet members 712A-B within a region of concentrated or focused magnetic flux density 726. The third magnet members 730A-B can be flux concentrating members that are directly attached to the surfaces of the first magnet members 712A-B that face the coils 708A-B. Representatively, the third magnet members 730A-B can be a soft magnetic material similar to the second magnet member 714, such as a steel material attached to the surfaces of the first magnet members 712A-B. For example, the third magnet member 730A can be attached to the outer surface of the first magnet member 712A that faces the coil 708A, and the third magnet member 730B can be attached to the inner surface of the first magnet member 712B that faces the coil 708B. In this regard, when the first magnet members 712A-B with the third magnet members 730A-B attached and the second magnet member 714 are translated 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 winding height of the coils 708A-B. Thus, as previously discussed, a primary magnetic flux density region can be maintained along the entire height of the coils 708A-B, which in turn can enable a greater excursion of the actuation surface (e.g., the actuation surface 118) connected to the moving portion 106.

[0047] Referring now to 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 the 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 one another (as well as 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 of the coil 808, and the second magnet member 814 is positioned radially inward of 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 produced by the first magnet member 812 within a region of concentrated or focused magnetic flux density 826. The third magnet member 830 can be a flux concentrating member that is directly attached to a surface of the first magnet member 812 that faces the coil 808. Representatively, the third magnet member 830 can be a soft magnetic material, such as a steel material, attached to a surface of the first magnet member 812 similar to the second magnet member 814. For example, the third magnet member 730 can be attached to an inner surface of the first magnet member 812 that faces the coil 808. In this regard, as the first magnet member 812 with the third magnet member 830 attached and the second magnet member 814 are translated together along the coil 808 positioned within a gap 816 formed by the magnet members, the region of focused magnetic flux density 826 also travels along the winding height of the coil 808. Thus, as previously discussed, a primary region of magnetic flux density can be maintained along the entire height of the coil 808, which in turn can enable greater displacement of an actuation surface (e.g., the actuation surface 118) coupled to the moving portion 106.

[0048] Referring now to Figure 9 , Figure 9A component 900 is shown that is similar to the previously discussed components 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 the component 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 concentration member (e.g., a steel structure) that concentrates the magnetic flux lines 924 produced by the first magnet members 912A-B within a region of concentrated or focused magnetic flux density 926. The third magnet members 930A-D can be flux concentration members that are directly attached to the surfaces of the first magnet members 912A-B. Representatively, the third magnet members 930A-D can be a soft magnetic material, such as a steel material, similar to the second magnet member 914, attached to the surfaces of the first magnet members 912A-B. For example, the third magnet member 930A can be attached to the inner surface of the first magnet member 912A facing the center of the component, the third magnet member 912B can be attached to the outer surface of the first magnet member 912A facing the coil 908A, the third magnet member 930C can be attached to the inner surface of the first magnet member 912B facing the coil 908B, and the third magnet member 930D can be attached to the outer surface of the first magnet member 912B facing away from the coil 908B. In this regard, when the first magnet members 912A-B and the second magnet member 914, with the third magnet members 930A-D attached, are translated together along the coils 908A-B positioned within the gaps 916A, 916B formed by the magnet members, the focused magnetic flux density region 926 also travels along the winding height of the coils 908A-B. Thus, as previously discussed, a primary magnetic flux density region can be maintained along the entire height of the coils 908A-B, which in turn can enable a greater excursion of an actuation surface (e.g., the actuation surface 118) connected to the moving portion 106.

[0049] Referring now to Figure 10 , Figure 10A component 1000 is shown that is similar to the previously discussed components in that it includes a stationary portion 104 and a moving portion 106 that moves relative to the stationary portion 104 along a translation axis 122. However, in the component 1000, the stationary 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 that are attached to one another (and to 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 of the coil 1008 and the second magnet member 1014 is positioned radially inward of 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 produced by the first magnet member 1012 within a region of concentrated or focused magnetic flux density 1026. The third magnet members 1030A-B can be flux concentrating members that are attached directly to the inner and outer surfaces of the first magnet member 1012. Representatively, the third magnet members 1030A-B can be a soft magnetic material, such as a steel material, similar to the second magnet member 1014, attached to the surfaces 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 that faces the coil 1008 and the third magnet member 1030B can be attached to the outer surface of the first magnet member 1012 that faces away from the coil 1008. In this regard, when the first magnet member 1012 with the third magnet members 1030A-B attached and the second magnet member 1014 are translated together along the coil 1008 positioned within the gap 1016 formed by the magnet members, the region of focused magnetic flux density 1026 also travels along the winding height of the coil 1008. Thus, as previously discussed, a primary region of magnetic flux density can be maintained along the entire height of the coil 1008, which in turn can enable a greater excursion of the actuation surface (e.g., the actuation surface 118) connected to the moving portion 106.

[0050] Referring now to Figure 11 , Figure 11An assembly 1100 is shown that is similar to the previously discussed assemblies in that the assembly includes a stationary portion 104 and a moving portion 106 that moves relative to the stationary portion 104 along a translation axis 122. However, in the assembly 1100, the stationary portion 104 includes a single coil 1108 and the moving portion 106 includes a pair of first magnet members 1112A, 1112B 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 members (e.g., magnet members 1014). The first magnet members 1112A can be radially polarized magnets positioned radially inboard of the coil 1108 and the first magnet members 1112B are positioned radially outboard of the coil 1108. The third magnet members 1130A-B can be flux concentrating members (e.g., steel structures) attached to the surfaces of the first magnet members 1112A-B that face the coil 1108. The third magnet members 1130A-B can be flux concentrating members that concentrate the magnetic flux lines 1124 produced by the first magnet members 1112A-B into a region of concentrated or focused magnetic flux density 1126. The third magnet members 1130A-B can be directly attached to the surfaces of the first magnet members 1112A-B that face the coil 1108. Representatively, the third magnet members 1130A can be a soft magnetic material such as steel material attached to the outer surface of the first magnet members 1112A and the third magnet members 1130B can be a soft magnetic material such as steel material attached to the inner surface of the first magnet members 1112B. In this aspect, when the first magnet members 1112A-B with the third magnet members 1130A-B attached thereto are translated together along the coil 1108, the coil is positioned within a gap 1116 formed by the magnet members, the region of focused magnetic flux density 1126 also travels along the winding height of the coil 1108. Thus, as previously discussed, a region of primary magnetic flux density can be maintained along the entire height of the coil 1108, which in turn can enable greater deflection of an actuation surface (e.g., actuation surface 118) connected to the moving portion 106.

[0051] Figure 12 A simplified schematic perspective view of an example electronic device in which a transducer assembly as described herein can be implemented is shown. As Figure 12As shown, the transducer assembly can be integrated in a consumer electronic device 1202 such as a smartphone, through which a user can place a call to a far-end user of a communication device 1204 over a wireless communication network; in another example, the transducer assembly can be integrated within the housing of a tablet 1206. These are merely two examples in which 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, e.g., a home audio system, any consumer electronic device with audio capabilities, or an audio system in a vehicle (e.g., a car infotainment system).

[0052] Figure 13 A block diagram showing some of the constituent components of an electronic device in which a transducer assembly as disclosed herein can be implemented is shown. The device 1300 can be any of several different types of consumer electronic devices, such as those discussed with reference to Figure 12 any of those consumer electronic devices discussed.

[0053] In this regard, the 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. The main processor 1312 can also interact with communication circuitry 1302, main power supply 1310, transducer 1318, and microphone 1320. The transducer 1318 can be a loudspeaker and / or a transducer assembly as described herein. The various components of the electronic device 1300 can be interconnected digitally by a software stack being executed by the processor 1312 and used or managed. Many of the components shown or described herein can be implemented as one or more dedicated hardware units and / or programmed processors (software being executed by the processor, e.g., processor 1312).

[0054] The processor 1312 controls the overall operation of the device 1300 by executing some or all of the operations of one or more application programs or operating system programs implemented on the device 1300, by executing instructions (software code and data) that can be found in the storage 1308. The processor 1312 may, for example, drive the display 1322 and receive user input through the user input interface 1324 (which can be integrated with the display 1322 as part of a single touch-sensitive display panel). In addition, the processor 1312 can send electrical current or signals (e.g., audio signals) to the transducer 1318 in order to facilitate operation of the transducer 1318. Representatively, the processor 1312 can send electrical current or signals to one or more components of a transducer assembly (e.g., assemblies 100-1100) to drive the components independently or together. For example, the coils 108-1108 can be driven independently by different channels on an amplifier, or together by the same channel, as needed for the application.

[0055] The storage 1308 provides relatively large amounts of "permanent" data storage using non-volatile solid state memory (e.g., flash storage) and / or dynamic non-volatile storage devices (e.g., rotating magnetic disks). The storage 1308 can include both local storage space and storage space on a remote server. The storage 1308 can store data as well as software components that control and manage the different functions of the device 1300 at a higher level.

[0056] In addition to the storage 1308, there can also be a memory 1314, also known as main memory or program memory, that provides relatively fast access to stored code and data that is being executed by the processor 1312. The memory 1314 can include solid state random access memory (RAM), such as static RAM or dynamic RAM. There can be one or more processors, such as the processor 1312, that run or execute various software programs, modules or sets of instructions (e.g., applications) that have been transferred to the memory 1314 for execution from the storage 1308 to perform the various functions described above.

[0057] The device 1300 can include communication circuitry 1302. The communication circuitry 1302 can include components for wired or wireless communication, such as two-way conversation and data transmission. For example, the communication circuitry 1302 can include RF communication circuitry coupled to an antenna so that a user of the device 1300 can place or receive calls over a wireless communication network. The RF communication circuitry can include an RF transceiver and a cellular baseband processor to enable calls over a cellular network. For example, the communication circuitry 1302 can include Wi-Fi communication circuitry so that a user of the device 1300 can place or initiate calls using a voice over internet protocol (VOIP) connection, transmit data over a wireless local area network.

[0058] The device can include a transducer 1318. The transducer 1318 can be a speaker and / or a transducer assembly, such as the transducer assembly described with reference to Figures 1 to 12 The transducer 1318 can be an electro-acoustic transducer or sensor that converts electrical signal input (e.g., acoustic input) into sound or vibrational output. The circuitry of the speaker can be electrically connected to the processor 1312 and the power source 1310 to facilitate speaker operation (e.g., diaphragm displacement, etc.) as previously discussed.

[0059] The device 1300 can also include a motion sensor 1304, also referred to as an inertial sensor, which can be used to detect movement of the device 1300, camera circuitry 1306 that implements digital camera functionality of the device 1300, and a main power source 1310, such as a built-in battery as a main power source.

[0060] While certain aspects have been described and shown in the drawings, it is to be understood that these aspects are merely illustrative of and not restrictive to the broad disclosure, and this disclosure is not limited to the specific constructions and arrangements shown and described since various other modifications can occur to those of ordinary skill in the art. Therefore, the description is to be regarded as illustrative in nature and not restrictive. Furthermore, to help interpret the claims, Applicant hereby states that any section of any claim that follows the provisions of 35 U.S.C. 112(f) is intended to invoke the provisions of 35 U.S.C. 112(f) in order to disclaim any subject matter not recited in that claim's preceding clauses.

Claims

1. A moving magnet motor comprising: a frame; a coil coupled to the frame and having a first end and a second end defining a winding height of the coil; a magnet assembly operable to move relative to the coil and the frame, the magnet assembly including a magnet and a flux concentration member, the magnet and the flux concentration member defining a gap in which the coil is positioned and a dominant magnetic flux density region along an entire winding height of the coil; and an actuation surface coupled with the magnet assembly, and wherein movement of the magnet assembly drives movement of the actuation surface.

2. The moving magnet motor of claim 1, wherein the coil is a continuous voice coil.

3. The moving magnet motor of claim 1, wherein the coil is a ring voice coil and the magnet is radially inward of the ring voice coil and the flux concentration member is radially outward of the ring voice coil.

4. The moving magnet motor of claim 1, wherein the coil is a ring voice coil and the flux concentration member is radially inward of the ring voice coil and the magnet is radially outward of the ring voice coil.

5. The moving magnet motor of claim 1, wherein the magnet is a radially polarized magnet.

6. The moving magnet motor of claim 1, wherein the flux concentration member is a steel structure.

7. The moving magnet motor of claim 1, wherein the flux concentration member is a radially polarized magnet.

8. The moving magnet motor of claim 1, wherein the flux concentration member is a first flux concentration member and the magnet assembly further includes a second flux concentration member directly coupled to the magnet.

9. The moving magnet motor assembly of claim 1, wherein the coil is a first voice coil, the moving magnet motor further including a second voice coil positioned radially outward of the first voice coil.

10. The moving magnet motor assembly of claim 9, wherein the first voice coil and the second voice coil have a same current direction and a same orientation.

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

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

13. The moving magnet motor of claim 1, wherein the frame comprises an electronic device housing. ​ 14. A loudspeaker moving magnet motor assembly comprising: a continuous voice coil coupled to a frame; a diaphragm positioned over the continuous voice coil and coupled to the frame; and a magnet assembly coupled to the diaphragm, the magnet assembly having a first magnet member and a second magnet member that define a gap in which the continuous voice coil is positioned and that are operable to concentrate a magnetic flux density toward the continuous voice coil and translate along the continuous voice coil to drive movement of the diaphragm along a translation axis.

15. The loudspeaker moving magnet motor assembly of claim 14, wherein the magnet assembly has a range of displacement along the translation axis defined by a height of the continuous voice coil.

16. The loudspeaker moving magnet motor assembly of claim 14, 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.

17. The loudspeaker moving magnet motor assembly of claim 14, further comprising a third magnet member.

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

19. The loudspeaker moving magnet motor assembly of claim 18, wherein the second magnet member is a steel structure positioned between the first continuous voice coil and the second continuous voice coil and the first magnet member and the third magnet member are positioned along sides of the first continuous voice coil and the second continuous voice coil opposite the second magnet member.

20. The loudspeaker moving magnet motor assembly of claim 18, wherein the first magnet member, the second magnet member, and the third magnet member are positioned along different sides of the first continuous voice coil and the second continuous voice coil and at least one of the first magnet member, the second magnet member, and the third magnet member comprises a radially polarized magnet. ​

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