Vibration actuator and electric device

Abstract

This vibration actuator that can be miniaturized includes: a movable body that has a rectangular cross-section orthogonal to the axial direction and has a plurality of magnets which form a pair and are arranged in orientations such that identical magnetic poles face each other in the axial direction; a rectangular coil that surrounds the magnets in a direction orthogonal to the axial direction; and a protective wall part that has a rectangular cylindrical shape and is disposed between the coil and the magnets. The vibration actuator includes a fixed body that accommodates, inside the protective wall part via an elastic body, the movable body so as to be capable of reciprocating in the axial direction.

Description

Vibration actuator and electrical equipment

[0001] The present invention relates to a vibration actuator and an electrical device equipped with the same.

[0002] Electrical devices with a vibration function generally include an actuator (vibration actuator) as a vibration source. The electrical device can drive the vibration actuator to transmit vibrations to a user, allowing the user to experience the vibrations.

[0003] The electrical devices include portable game terminals, controllers (game pads, etc.) for stationary game consoles, mobile communication terminals such as mobile phones and smartphones, and mobile information terminals such as tablet PCs (Personal Computers), etc. The electrical devices also include various health care devices and beauty devices that provide massages and the like to users.

[0004] An example of a conventional vibration actuator has a coil arranged inside a cylindrical case, a mover having a permanent magnet, and an elastic member that supports the mover inside the coil so that it can vibrate in the axial direction (see, for example, Patent Document 1). In this type of vibration actuator, when a current of a predetermined frequency is passed through the coil, the mover reciprocates, i.e., vibrates, due to the driving force of a voice coil motor composed of the coil and the permanent magnet, and vibrations are output to the outside of the vibration actuator.

[0005] Japanese Patent Application Laid-Open No. 2020-054018

[0006] In the vibration actuator described above, the mover and elastic member form a relationship that constitutes a vibration model of a spring-mass system. In other words, when an AC wave with a frequency equal to the resonant frequency of the spring-mass system is input to the coil, the mover enters a resonant state, and high-output vibrations are obtained from the vibration actuator. In other words, utilizing resonance improves the drive efficiency of the vibration actuator.

[0007] In the vibration actuator described above, which uses resonance to improve drive efficiency, miniaturization is desirable. Furthermore, when miniaturization is sought and low-frequency vibrations are to be generated, it is conceivable to use softer springs with smaller elastic coefficients. Therefore, if the conventional structure is made smaller and the elastic coefficient of the spring supporting the movable body within the cylindrical case is reduced, it becomes difficult to support the movable body in a suitable vibration direction.

[0008] An object of the present invention is to provide a vibration actuator and an electrical device that can be miniaturized while suitably generating vibrations.

[0009] One aspect of the vibration actuator according to the present invention is configured to have a movable body having a plurality of magnets arranged in pairs with the same magnetic poles facing each other in the axial direction, the movable body having a rectangular cross section perpendicular to the axial direction, a rectangular coil surrounding the magnets in a direction perpendicular to the axial direction, and a rectangular cylindrical protective wall portion arranged between the coil and the magnets, and a fixed body that houses the movable body inside the protective wall portion via an elastic body so that the movable body can move back and forth in the axial direction.

[0010] One aspect of the electrical device according to the present invention is a portable or wearable electrical device that incorporates the vibration actuator having the above-described configuration.

[0011] According to the present invention, it is possible to achieve size reduction while suitably generating stronger vibrations.

[0012] FIG. 1 is an external perspective view of a vibration actuator according to a first embodiment, as seen from the front side. FIG. 2 is a plan view of the vibration actuator. FIG. 3 is an exploded perspective view of the vibration actuator with the case removed. FIG. 4 is a perspective view of the actuator unit with the base removed. FIG. 5 is an exploded perspective view of the actuator unit with the movable body removed. FIG. 6 is a perspective view of the movable body connected to the elastic unit. FIG. 7 is a cross-sectional perspective view taken along line A-A in FIG. 2. FIG. 8 is a perspective view of the coil assembly as seen from the bottom side. FIG. 9 is an exploded perspective view of the movable body. FIG. 10 is a plan view of the elastic unit. FIG. 11 is an exploded perspective view of the elastic unit. FIGS. 12A, 12B, and 12C are diagrams illustrating the spiral direction of the leaf spring of the elastic unit. FIG. 13A is an exploded perspective view of a first modified elastic unit. FIG. 13B is a longitudinal cross-sectional view of the first modified elastic unit. FIG. 14 is a diagram illustrating a second modified elastic unit. FIG. 15 is an exploded perspective view of the second modified elastic unit. FIG. 16 is a diagram illustrating a third modified elastic unit. FIG. 17 is an exploded perspective view of Modified Example 3 of the elastic unit. FIG. 18 is a diagram showing the vibration characteristics of the vibration actuator according to the first embodiment. FIG. 19 is a schematic diagram showing the magnetic circuit of the vibration actuator according to the first embodiment. FIG. 20 is a vertical cross-sectional perspective view of the vibration actuator according to the second embodiment. FIG. 21 is a perspective view showing a movable body in the vibration actuator according to the second embodiment with the elastic unit removed. FIG. 22 is an exploded perspective view of the movable body in the vibration actuator according to the second embodiment. FIG. 23 is an external perspective view of the vibration actuator according to the third embodiment, as seen from the front side. FIG. 24 is a plan view of the same vibration actuator. FIG. 25 is a cross-sectional perspective view taken along line B-B in FIG. 24. FIG. 26 is an exploded perspective view of the same vibration actuator with the case removed. FIG. 27 is a perspective view of the actuator unit with the end spacers removed. FIG. 28 is an exploded perspective view of the actuator unit with the movable body removed. FIG. 29 is a perspective cross-sectional view showing the configuration of the coil assembly. FIG. 30 is a plan view showing the positional relationship between the ribs and the movable body in the actuator unit. FIG. 31 is a plan view of the bobbin in FIG. 30.FIG. 32 is a plan view showing a modified example of the actuator unit. FIG. 33 is an exploded perspective view of the movable body. FIG. 34 is a vertical cross-sectional view of the elastic unit. FIG. 35 is a schematic view showing a magnetic circuit of a vibration actuator according to the third embodiment. FIG. 36 is a vertical cross-sectional view showing the main configuration of a vibration actuator according to the fourth embodiment. FIG. 37 is an external perspective view of the actuator unit of the vibration actuator shown in FIG. 36. FIG. 38 is a vertical cross-sectional view showing the main configuration of a first modified example of the vibration actuator according to the fourth embodiment. FIG. 39 is an external perspective view of the actuator unit of the vibration actuator shown in FIG. 38. FIG. 40 is an external perspective view of an actuator unit in a second modified example of the vibration actuator according to the fourth embodiment. FIG. 41 is a vertical cross-sectional view showing the main configuration of a vibration actuator according to the fifth embodiment. FIG. 42 is a perspective cross-sectional view showing the main configuration of the vibration actuator shown in FIG. 41. FIG. 43 is a sectional perspective view showing the main configuration of a vibration actuator according to the sixth embodiment. FIG. 44 is an exploded perspective view of the movable body of the vibration actuator shown in FIG. 43. FIG. 45 is a vertical cross-sectional view showing the main configuration of a vibration actuator according to the seventh embodiment. FIG. 46 is an external perspective view of the actuator unit of the vibration actuator shown in FIG. 45. FIG. 47 is an external perspective view showing the movable body and elastic support part within the actuator unit. FIG. 48 is an external perspective view of the actuator unit of the vibration actuator of the eighth embodiment. FIG. 49 is an external perspective view of the leaf spring of the actuator unit shown in FIG. 48. FIG. 50 is an exploded perspective view showing the movable body of the actuator unit of FIG. 48. FIG. 51 is an external perspective view of the actuator unit of the vibration actuator of the ninth embodiment. FIG. 52 is an exploded perspective view of the actuator unit shown in FIG. 51. FIG. 53 is an exploded perspective view of the elastic unit of the actuator unit shown in FIG. 52. FIG. 54 is a longitudinal sectional view showing the configuration of the main parts of a vibration actuator having the actuator unit shown in FIG. 52. FIG. 55 is a perspective sectional view showing the configuration of the main parts of a vibration actuator as another variation 1 of the vibration actuator of the first embodiment. A perspective view of the coil assembly from which the tubular conductor 300 has been removed in the vibration actuator of FIG. 56.57 is a perspective cross-sectional view of the coil assembly of the vibration actuator of FIG. 55, with the tubular conductor removed. FIG. 58 is a perspective cross-sectional view showing the configuration of a main part of another modified example 2 of the vibration actuator. FIG. 59 is a perspective cross-sectional view of the coil assembly of the vibration actuator of FIG. 58, with the movable body removed. FIG. 60 is a perspective cross-sectional view showing the configuration of a main part of another modified example 3 of the vibration actuator. FIG. 61 is a perspective cross-sectional view of the coil assembly of the vibration actuator of FIG. 60, with the movable body removed. FIG. 62 is a perspective cross-sectional view showing the configuration of a main part of another modified example 4 of the vibration actuator. FIG. 63 is a perspective cross-sectional view of the coil assembly of the vibration actuator of FIG. 62, with the movable body removed. FIG. 64 is a perspective cross-sectional view showing the configuration of a main part of another modified example 5 of the vibration actuator. FIG. 65 is a perspective cross-sectional view of the coil assembly of the vibration actuator of FIG. 64, with the movable body removed. FIG. 66 is a perspective cross-sectional view showing the configuration of a main part of another modified example 6 of the vibration actuator. FIG. 67 is a perspective cross-sectional view of the coil assembly of the vibration actuator of FIG. 66, with the movable body removed. Fig. 68 is a perspective cross-sectional view showing the configuration of the main parts of another modified example 7 of the vibration actuator. Fig. 69 is a perspective cross-sectional view of the coil assembly with the movable body removed in the vibration actuator of Fig. 68. Fig. 70 is a diagram showing an example of an electronic device in which the vibration actuator is mounted. Fig. 71 is a diagram showing an example of an electronic device in which the vibration actuator is mounted.

[0013] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0014] (Embodiment 1) [Configuration of Vibration Actuator] Fig. 1 is an external perspective view of a vibration actuator according to this embodiment 1 as seen from the front side, and Fig. 2 is a plan view of the same vibration actuator. Fig. 3 is an exploded perspective view of the same vibration actuator with the case removed, Fig. 4 is a perspective view of the actuator unit with the base removed, and Fig. 5 is an exploded perspective view of the actuator unit with the movable body removed. Fig. 6 is a perspective view of the movable body connected to the elastic unit, and Fig. 7 is a perspective view of the cross section taken along line A-A in Fig. 2.

[0015] In the following description, the terms "upper" and "lower" in terms such as "upper side" and "lower side" are used for convenience to make it easier to understand the configuration and behavior of the vibration actuator 1 according to this embodiment. When the vibration actuator 1 is mounted on an electrical device (see Figures 70 and 71), the "upper" and "lower" described here may be reversed, or may be rotated left and right, or may be at an angle. Incidentally, in this embodiment, the up and down direction is the vibration direction of the movable body in the vibration actuator 1, with the "upward direction" being one of the vibration directions and the "downward direction" being the other of the vibration directions. In other words, the vibration actuator 1 is a linear actuator that vibrates the movable body 60 linearly in the up and down direction.

[0016] Furthermore, in the following description, unless otherwise specified, the term "radial direction" refers to a direction extending radially or centrifugally around the central axis CA that extends in the up-down direction in the vibration actuator 1. Furthermore, the terms "outside" and "inside" in terms such as "outside" and "inside" refer to the outward and inward directions in the radial direction around the central axis CA. Furthermore, unless otherwise specified, the term "circumferential direction" refers to a direction extending around the central axis CA.

[0017] Furthermore, it goes without saying that the expressions relating to shapes used in the following description are merely expedient expressions for the purpose of describing simple outlines, and do not necessarily represent geometrically accurate definitions of figures. The shapes of the entire device or each component part described herein are merely examples, and the present invention is not limited to the shapes exemplified in each embodiment.

[0018] The vibration actuator 1 according to the first embodiment is mounted as a vibration generating source in an electronic device such as a portable game terminal device (for example, the game controller GC shown in FIG. 70) and realizes the vibration function of the electronic device. Such electronic devices also include mobile devices such as smartphones (for example, the mobile terminal M shown in FIG. 71). The vibration actuator 1 is mounted in each device such as a portable game terminal device or a mobile device, and vibrates when driven to notify the user of an incoming call or to provide a sense of operation or realism.

[0019] 1 to 3, the vibration actuator 1 of this embodiment has a hollow case 10 and an actuator unit 20 that is housed in the hollow case 10 together with end spacers 22, 24. The actuator unit 20 has a coil assembly 26 that has a coil 30, a movable body 60 that is housed in the coil assembly 26 and has magnets 50 (52, 54), and an elastic unit (elastic body) 80 that movably supports the movable body 60. The coil assembly 26, together with the case 10 and the end spacers 22, 24, constitutes a fixed body.

[0020] <Case 10> In the vibration actuator 1, the case 10 constitutes a fixed body together with the coil assembly 26 of the actuator unit 20.

[0021] The case 10 is formed so as to cover at least the periphery of the actuator unit 20, that is, so as to surround the actuator unit 20 in a direction perpendicular to the axial direction thereof.

[0022] The case 10 is made of a magnetic material and functions as a magnetic shield. The case 10 is formed of a cylindrical case body 12 with an open end and a closed end, and a magnetic metal (SECC, etc.) plate together with a bracket 14. If a magnetic shield is not required on the open side of the case body 12, the bracket 14 may be made of a non-magnetic material (non-magnetic metal, non-magnetic resin, etc.).

[0023] The case 10 has a cylindrical case body 12 with a bottom and a plate-like bracket 14 that closes the opening of the case body 12 .

[0024] The case body 12 surrounds the outer peripheral surface of the bobbin 40 of the actuator unit 20 and includes a rectangular cylindrical magnetic body that is positioned to cover the radially outer side of the central coil 32 and the upper and lower coils 34, 36. The actuator unit 20 is housed within the case body 12, and a bracket 14 is placed on the actuator unit 20 within the case body 12 to close the opening of the case body 12.

[0025] The case body 12 is configured by covering one opening of a rectangular cylindrical peripheral wall portion 122 with a bottom portion 124 .

[0026] The bracket 14 closes the opening of the case body 12 and corresponds to the shape of one surface (top surface) of the actuator unit 20 .

[0027] The bracket 14 has a shape that engages with the terminal lead-out portion 47 of the actuator unit 20 by cutting two corners of the rectangular plate-like body.

[0028] A conductive board 16 is disposed on the upper part of the bracket 14. The conductive board 16 is connected to a terminal connector 48 in a terminal lead-out portion 47 that protrudes from a corner of the bracket 14, and supplies power to the coil 30.

[0029] The case 10 covers the central coil 32 , upper and lower coils 34 , 36 , magnets 52 , 54 , central yoke (first yoke) 62 and upper and lower yokes (second yokes) 64 , 66 , and prevents magnetic flux from leaking outside the vibration actuator 1 .

[0030] In the case 10, the bracket 14 and the bottom surface portion 124 are each a movement range restricting portion having a hard stop (movement range limiting) function that restricts the movement range of the movable body 60. The bracket 14 and the bottom surface portion 124 each prevent the movable body 60 from receiving an external impact and moving within a movement range larger than the normal vibration range. Specifically, the bracket 14 and the bottom surface portion 124 restrict the length to the elastic units 81, 82 attached to the upper and lower ends of the actuator unit 20 (coil assembly 26).

[0031] <Actuator Unit 20> The actuator unit 20 is formed in a cylindrical shape and is housed in the case 10 with end spacers 22, 24 engaged with openings at both ends (upper and lower ends) spaced apart in the axial direction.

[0032] The actuator unit 20 has a cylindrical coil assembly 26 as a fixed body, a movable body 60 having a magnet and a yoke, and a pair of elastic units 81 and 82 .

[0033] In the actuator unit 20, the coil 30 and the magnet form a magnetic circuit that vibrates the movable body 60. The magnetic circuit does not necessarily require a yoke. When electricity is applied to the coil 30 from a power supply unit (which may be a drive board), the coil 30, magnet, and yoke work together to cause the movable body 60 to reciprocate in the vibration direction inside the coil assembly 26 in the case 10.

[0034] <Coil assembly 26> The coil assembly 26 is a cylindrical body having a coil 30 and a bobbin 40. The coil assembly 26 supports the movable body 60 within the coil assembly 26 via an elastic unit 80, and accommodates the movable body 60 so that it can freely move back and forth in the axial direction (vibration direction). The coil assembly 26 is formed in a square cylindrical shape, for example, a rectangular cylindrical shape. In this case, the coil 30 and the bobbin 40 are also formed in a rectangular cylindrical shape. The coil assembly 26 (coil 30, bobbin 40) and the movable body 60 have an outer shape that is rectangular parallelepiped or cubic. These may also be formed in a polygonal shape.

[0035] <Coils 30 (central coil 32, upper and lower coils 34, 36)> The coils 30 (32, 34, 36) are configured in a number corresponding to the number of magnets 50, and are held on the bobbin in a state where they are concentrically arranged around the central axis CA and juxtaposed along the direction of the central axis CA (corresponding to the "axial direction", which in this embodiment is the same direction as the up and down direction).

[0036] The coils 30 are arranged spaced apart in a direction perpendicular to the axial direction on the outer peripheral surface of the central portion of a movable body having a pair of magnets 50 (52, 54). In the vibration actuator 1, the coils 30 are used to generate a driving source for the vibration actuator 1 together with the magnets 50 (52, 54) and yokes (62, 64, 66), with the axial direction of the coils 30 (32, 34, 36) (the magnetization direction of the magnets 50) being the vibration direction.

[0037] The coil 30 has a central coil 32 arranged in a position surrounding the axial center of the pair of magnets, and a pair of upper and lower coils 34, 36 arranged on both axial sides of the central coil 32. For convenience, the coil 30 is also referred to as coil 30 (32, 34, 36). When driven (vibrating), the coils 30 (32, 34, 36) are energized and constitute a voice coil motor together with the magnets 50 (52, 54) and yokes (62, 64, 66).

[0038] Preferably, the central coil 32 and the upper and lower coils 34, 36 have the same outer shape, the central coil 32 has the longest vertical length, and the upper and lower coils 34, 36 have the same vertical length.

[0039] The vertical length of the central coil 32 is a length that falls within the range of movement of the vertical center position of the movable body 60, that is, the vertical center position between the pair of magnets 50 (52, 54). In other words, when the movable body 60 moves, the vertical center position of the movable body 60 (for example, the center position of the central yoke) is a length that falls within the vertical range of the upper and lower coils 34, 36.

[0040] The central coil 32 is disposed opposite to the central position of the movable body 60 having a pair of magnets 50 (52, 54) that constitutes a circuit with the highest magnetic efficiency of the movable body 60.

[0041] The upper and lower coils 34 and 36 are arranged at positions symmetrical in the up and down direction with respect to the middle position of the range of motion determined by the maximum amplitude of the up and down movement of the movable body 60 .

[0042] The central coil 32 and the upper and lower coils 34, 36 are wired so that when current is applied, the movable body 60 moves linearly back and forth in the axial direction. The width of the central coil 32 is positioned within the movable range of the central yoke 62.

[0043] The central coil 32 and the upper and lower coils 34, 36 are configured so that current flows in opposite directions. For example, the central coil 32 and the upper and lower coils 34, 36 may be configured from a single coil wire, in which case the central coil 32 and the upper and lower coils 34, 36 are configured so that the coil wire is wound in opposite directions, and the coil wire is wound in the same direction in the upper and lower coils 34, 36. In other words, the central coil 32 and the upper and lower coils 34, 36 are configured so that current flows in opposite directions when energized.

[0044] Furthermore, when the central coil 32 and the upper and lower coils 34, 36 are configured from a single coil wire, the coil connection portion corresponding to the portion where the central coil 32 and the upper and lower coils 34, 36 are connected to each other is arranged across multiple intermediate flanges 43, 44 of the bobbin.

[0045] In addition, both ends of the wires of the upper and lower coils 34, 36, which correspond to the portions opposite to the portion connected to the central coil 32, are respectively connected to connection terminals 48 in the terminal lead-out portion 47 from the upper flange 45 that separates the upper coil 34.

[0046] 8 is a perspective view of the coil assembly as viewed from the bottom side. In the coil assembly 26, one end of each of the upper and lower coils 34, 36 (both wire ends) is connected to a power supply via a connection terminal 48 of a terminal lead-out portion 47. For example, each end of the coils 30 (32, 34, 36) is connected to an AC supply, and AC power (AC voltage) is supplied from the AC supply to the coils 30 via a conductive board 16. This separates the coils 30 (32, 34, 36) from the magnets 50 (52, 54) and the yokes (62, 64, 66), enabling them to generate thrust that moves axially.

[0047] The coil axis of the coil 30 (32, 34, 36) is preferably arranged coaxially with the axis of the bobbin 40 or the axis of the magnet 50 (52, 54).

[0048] If the coils 30 (32, 34, 36) are configured to be formed by winding a coil wire around the bobbin 40, the coils 30 (32, 34, 36) can be assembled without using self-bonding wire. In other words, there is no need to use air-core coils as the coils 30 (32, 34, 36), which reduces the cost of the coils themselves and ultimately the cost of the entire vibration actuator.

[0049] The bobbin 40 holds the coil 30 (32, 34, 36) wound around its outer circumferential surface, and the inner circumferential surface 42a of the bobbin body 42, which is a central cylindrical body that is the bobbin body, surrounds the yoke and guides the movement of the movable body 60 having the magnet 50 (52, 54).

[0050] The inner surface 42a of the bobbin 40 covers the inner surfaces of the coil 30 (central coil 32, upper and lower coils 34, 36) and functions as a protective wall that protects the central coil 32 and upper and lower coils 34, 36 from direct contact or collision with the movable body 60.

[0051] The bobbin 40 is a cylindrical body made of a non-magnetic and non-conductive resin material such as phenolic resin, polybutylene terephthalate (PBT), etc. In this embodiment, the bobbin is made of a material containing phenolic resin, such as Bakelite, which has high flame retardancy.

[0052] The bobbin 40 is made of a material containing phenolic resin, which increases its flame resistance and prevents deformation due to heat generation caused by Joule heat when a current flows through the coil 30 it holds, improving safety during operation. In addition, the dimensional accuracy of the bobbin 40 is improved, which increases the positional accuracy of the coil 30 and reduces variations in vibration characteristics.

[0053] The bobbin 40 has recesses 40a, 40b, and 40c that open in the circumferential direction and in which the central coil 32 and the upper and lower coils 34, 36 are arranged, on the outer periphery of a cylindrical bobbin body 42. The recesses 40a, 40b, and 40c are formed by the outer periphery of the bobbin body 42, a plurality of intermediate flanges 43, 44 that protrude radially from the outer periphery, and upper and lower flanges 45, 46 at both ends that define the movable range of the movable body 60.

[0054] The central coil 32, upper coil 34, and lower coil 36 are respectively arranged in recesses 40a, 40b, and 40c on the outer periphery of the bobbin body 42. The coils 30 (32, 34, and 36) are coaxial (coil axes) and are arranged in positions facing the yokes 62, 64, and 66 of the movable body 60, with the bobbin body 42 interposed therebetween, in a direction perpendicular to the axial direction.

[0055] The inner peripheral surface 42a of the bobbin body 42 is disposed opposite the outer peripheral surface 60a of the movable body 60 at a predetermined distance. This predetermined distance allows the movable body 60 to move in the axial direction, which is the vibration direction, without coming into contact with the inner peripheral surface 42a. The bobbin body 42 is configured to inhibit contact between the magnets 50 (52, 54) 30 and the coils 30 (32, 34, 36), and the movable body 60 can move back and forth along the inner peripheral surface 42a without coming into contact with the inner peripheral surface 42a.

[0056] The bobbin body 42 functions as a protective wall that protects the coils 30 (32, 34, 36) from collisions when the movable body 60 arranged inside is driven. The thickness of the bobbin body 42 is set to a thickness that provides strength such that the outer coils 30 (32, 34, 36) are not affected even when the moving movable body 60 comes into contact with the bobbin body 42.

[0057] The intermediate flanges 43, 44 are disposed at positions sandwiching the central coil 32. The intermediate flanges 43, 44 are formed with cutouts 432, 442, respectively, and coil connecting portions that connect the coils 30 (32, 34, 36) are disposed therein.

[0058] The upper and lower flanges 45, 46 are formed to protrude radially from both opening edges of the bobbin body 42, and have cylindrical opening edges 452, 462 that rise axially from the tips of the upper and lower flanges 45, 46.

[0059] The opening edges 452, 462 constitute both ends of the bobbin 40 that are spaced apart in the axial direction of the bobbin body 42 (which is the vibration direction and also the up-down direction in this embodiment).

[0060] Elastic units 80 (81, 82) are connected to the opening edge portions 452, 462, respectively. As a result, the elastic units 80 (upper elastic unit 81 and lower elastic unit 82) are connected to both ends (upper and lower ends in this embodiment) of the movable body 60 formed by the upper and lower flanges 45, 46.

[0061] The opening edge portions 452 and 462 are arranged so as to surround the central opening 400 of the bobbin body 42, and are formed in the shape of a rectangular frame with an outer shape larger than that of the central opening 400.

[0062] The opening shape of the opening edge portions 452, 462 is formed into a shape that abuts against and supports the outer periphery of the elastic unit 80, and engages with the elastic unit 80. The opening edge portions 452, 462 have cutout portions 4522, 4622 that engage with the protrusions 807, 809 of the elastic unit 80, and the protrusions 809, 807 engage with the cutout portions 4522, 4622 to position and fix the elastic unit 80. The inner periphery surfaces of the opening edge portions 452, 462 are inclined, and form a movable area for the elastic unit 80 (81, 82).

[0063] The upper and lower flanges 45, 46, together with the end spacers 22, 24, are positioned to sandwich the elastic unit 80, and form a deformation region in the vibration direction (vertical and axial direction) of the elastic unit 80, i.e., a movable range of the movable body 60. The movable range is formed at both axial ends within the case 10 by the internal space of the opening edge portions 452, 462, the end spacers 22, 24, the bottom surface portion 124 of the case main body 12, and the bracket 14.

[0064] Terminal lead-out portions 47 protrude in the axial direction from some of the corners of opening edge portion 452. Leg portions 480 of the same shape as terminal lead-out portions 47 are provided on opening edge portion 462 at positions corresponding to terminal lead-out portions 47 of opening edge portion 452, so as to protrude in a similar manner.

[0065] The end spacers 22, 24 are arranged on both ends of the actuator unit 20 via the elastic units 80. The end spacers 22, 24 are arranged to separate the elastic units 80 from the bottom surface 124 of the case 10 and the bracket 14. The end spacers 22, 24 accommodate the actuator unit 20 in the case 10 in a state where movement is restricted.

[0066] The end spacers 22, 24 are frame-like bodies formed to correspond to the shape of the elastic units 80 (81, 82) arranged at both ends of the actuator unit 20, and a central opening ensures a deformation area for the elastic units 80. The end spacers 22, 24 are of the same shape and have inclined sides 23 with which the terminal lead-out portion 47 and the leg portion 480 respectively engage.

[0067] The end spacers 22 and 24 are arranged at both ends of the actuator unit 20 by engaging the terminal lead-out portion 47 or the leg portion 480 with the inclined side portion 23 , and form a rectangular parallelepiped that is accommodated in the case 10 as a whole.

[0068] The end spacers 22, 24 ensure a deformation area for the elastic unit 80 (81, 82), i.e., a movement area for the movable body, and also position the actuator unit 20. This allows the actuator unit 20 to generate suitable vibrations without moving within the case 10.

[0069] The end spacers 22, 24 are non-magnetic resin spacers, and are molded from a resin such as polyethylene terephthalate (PBT).

[0070] <Movable body 60> The movable body 60 is supported by elastic units 80 (81, 82) connected at the upper and lower ends inside the cylindrical coil assembly 26 of the fixed body so as to be reciprocatable along the inner circumferential surface 42a of the bobbin body 42. In the vibration actuator 1, the movable body 60 is supported between the bracket 14 and the bottom surface portion 124 inside the case 10 so as to be reciprocatable in opposing directions.

[0071] 9 is an exploded perspective view of the movable body. As shown in FIGS. 5 to 7 and 9, the movable body 60 has magnets 50 (52, 54), yokes (central yoke 62, upper and lower yokes 64, 66), sleeves 72, 74, a shaft 76, and spring stop members (fastening members) 77, 78. The movable body 60 includes a rectangular parallelepiped magnetic body portion having the magnets 50 (52, 54) and yokes (central yoke 62, upper and lower yokes 64, 66), and the movable body 60 as a whole has a rectangular outer shape when viewed in the axial direction, constituting a prismatic movable body.

[0072] <Magnet 50 (Pair of Magnets 52, 54)> The magnet 50 includes a pair of magnets 52, 54 arranged with the same magnetic poles facing each other. The pair of magnets 52, 54 are magnetized in the axial direction, are arranged on either side of a central yoke 62, and are sandwiched between a pair of upper and lower yokes 64, 66 on the axial outer side.

[0073] The magnets 52, 54, central yoke 62, and upper and lower yokes 64, 66 each have a continuous through-hole formed therein, and a shaft 76 is inserted through these through-holes, with both ends 762, 764 of the shaft 76 fixed to the sleeves 72, 74.

[0074] The magnets 52, 54, the central yoke 62, and the upper and lower yokes 64, 66 are arranged in layers in the axial direction.

[0075] The magnets 52, 54, the central yoke 62, and the upper and lower yokes 64, 66 have the same outer shape and are each formed in the shape of a rectangular plate.

[0076] The magnets 52, 54, central yoke 62, and upper and lower yokes 64, 66 form a rectangular (rectangular) magnetic body portion in the movable body, and the outer surface of the magnetic body portion faces the inner surface 42a of the bobbin body 42 at a predetermined distance inside the inner surface 42a.

[0077] The magnets 52, 54 are of the same shape and are arranged so that the same magnetic poles face each other in the axial direction. A central yoke 62 is arranged between the magnets 52, 54. The thickness (axial length) of the magnets 52, 54 is greater than the thickness (axial length) of the central yoke 62, and for example, the height is approximately twice or more the thickness of the central yoke 62.

[0078] In the movable body 60, the center in the thickness direction of the central yoke 62 is the axial center of the movable body 60, and is disposed at a position facing the axial center of the central coil 32 in a direction perpendicular to the axial direction.

[0079] The magnets 52, 54 each have a thickness (axial length) that straddles the central coil 32 and the upper and lower coils 34, 36. The upper and lower yokes 64, 66 are disposed in positions that face the upper and lower coils 34, 36 perpendicular to the axial direction.

[0080] The magnets 52, 54 are arranged so that, when the movable body 60 is moved, at least a portion of them faces the central coil 32. The magnets 52, 54 are arranged so that the yoke 62 is sandwiched between surfaces 52 a, 54 a of the same magnetic pole (north poles or south poles).

[0081] The magnets 52 and 54 are made of, for example, sintered neodymium, and have through holes 522 and 542 formed in the center thereof, respectively.

[0082] <Central yoke 62, upper and lower yokes 64, 66> The central yoke 62 and upper and lower yokes 64, 66 are magnetic bodies formed from a magnetic metal such as SECC. The central yoke 62 and upper and lower yokes 64, 66, together with the magnets 50 (52, 54) and coils 30 (32, 34, 36), form a magnetic circuit. The case 10 may also be included in the magnetic circuit.

[0083] The central yoke 62 and the upper and lower yokes 64, 66 are arranged to cover the magnetic pole faces of the magnets 52, 54, respectively. As a result, the central yoke 62 and the upper and lower yokes 64, 66 concentrate the magnetic flux of the magnet 50 (52, 54) and allow it to flow efficiently without leakage, effectively distributing the magnetic flux flowing between the magnet 50 (52, 54) and the coil 30 (32, 34, 36).

[0084] Furthermore, the central yoke 62 and the upper and lower yokes 64, 66 function as part of the magnetic circuit, and also form a magnetic body together with the magnets 52, 54 in the movable body 60, and function as weights.

[0085] The central yoke 62 and the upper and lower yokes 64 and 66 are formed so that their outer circumferential surfaces are flush with the outer circumferential surfaces of the magnets 52 and 54 .

[0086] The central yoke 62 and the upper and lower yokes 64, 66 are arranged symmetrically above and below the magnets 52, 54, respectively, on the front and back surfaces of the central yoke 62. The central yoke 62 and the upper and lower yokes 64, 66 are attracted to the magnets 52, 54 and may be fixed to the magnets 52, 54 with, for example, a thermosetting adhesive such as epoxy resin or an anaerobic adhesive.

[0087] Through holes 622, 642, 662 that communicate in the axial direction with the through holes 522, 542 of the magnets 52, 54 are provided in the respective centers of the central yoke 62 and the upper and lower yokes 64, 66. A shaft 76 is inserted through the magnets 52, 54 and is positioned on the central axis of the movable body 60.

[0088] In the default non-vibrating state, the upper and lower yokes 64, 66 are positioned opposite the upper and lower coils 34, 36, respectively. They are formed as circular flat plates with the same surface shape as the magnets 52, 54, and their axial centers are located at the same height perpendicular to the axial direction. The upper and lower yokes 64, 66 prevent leakage flux in the magnetic circuit formed by the magnets 52, 54 and the coils 30 (32, 34, 36) sandwiching the central yoke 62, thereby creating an effective flow of magnetic flux.

[0089] <Sleeves 72, 74> The sleeves 72, 74 have the function of fixing the magnetic bodies (magnets 52, 54, central yoke 62, and upper and lower yokes 64, 66) to the elastic units 81, 82, and also function as weights for the movable body 60. The sleeves 72, 74 are arranged symmetrically in the axial direction so as to sandwich the magnets 50 (52, 54), central yoke 62, and upper and lower yokes 64, 66, and increase the vibration output of the movable body 60.

[0090] The sleeves 72, 74 are made of a non-magnetic material such as sintered copper metal, and are cylindrical bodies arranged radially outward from the through holes (through portions) 722, 742 along the central axis of the movable body 60. The sleeves 72, 74 are arranged between the pair of magnets 52, 54 and the elastic units 81, 82. In this embodiment, the sleeves 72, 74 are arranged between the pair of magnets 52, 54, the central yoke 62, and the upper and lower yokes 64, 66 and the elastic units 81, 82.

[0091] Since the sleeves 72 and 74 are made of a non-magnetic material, magnetic flux from the magnetic bodies (magnets 52 and 54, central yoke 62, upper and lower yokes 64 and 66) does not flow vertically, but can flow toward the coil 30 (32, 34, 36).

[0092] The sleeves 72, 74 are formed in a truncated cone shape with through holes 722, 742 respectively provided in the central portion along the axial direction. That is, the axially outer surfaces (outer surfaces) of the sleeves 72, 74 are inclined downward from the central portion toward the radially outward direction, and are formed so that the axial thickness becomes thinner from the central portion toward the radially outward direction.

[0093] In this way, because the sleeves 72, 74 are not cylindrical but truncated cones, when the movable body 60 moves in the axial direction, the movable area can be widened without coming into contact with the elastic units 81, 82 (leaf spring 802). Note that by making the sleeves 72, 74 cylindrical, for example, the weight of the movable body 60 can be increased as desired.

[0094] The sleeves 72, 74 are fixed in an internally fitted state by inserting (for example, press-fitting) both end portions 762, 764 of the shaft 76 into one opening of the through-holes 722, 742, respectively.

[0095] The sleeves 72 and 74 are formed so as to contact the upper and lower yokes 64 and 66 over their entire surfaces.

[0096] The sleeves 72, 74 press the magnets 52, 54, central yoke 62, and upper and lower yokes 64, 66 from both ends of the shaft 76, stacking them axially and sandwiching them in close contact with each other.

[0097] Spring stop members 77 and 78 that connect the elastic units 81 and 82 are inserted into the sleeves 72 and 74 from the other openings of the through holes 722 and 742 , and the elastic units 81 and 82 are fastened via the spring stop members 77 and 78 .

[0098] The central end faces of the sleeves 72 and 74 where the other of the through holes 722 and 742 opens are in contact with and fixed to the elastic units 81 and 82 .

[0099] The shaft 76 is press-fitted and fixed between the magnets 52, 54 with their like poles butted together, and in a configuration in which both ends are sandwiched between the central yoke 62 and the upper and lower yokes 64, 66 (the magnetic body of the movable body 60). In this case, the vibration actuator 1 can be stably fixed to the magnetic body of the movable body 60 even in a configuration in which there is a strong repulsive force between the magnets 52, 54 with their like poles butted together.

[0100] Even if the movable body 60 has a pair of magnets 52, 54 arranged with the same magnetic poles facing each other, the shaft 76 that passes through them is fixed by press-fitting or the like to the sleeves 72, 74. As a result, both sleeves 72, 74 can be stably fixed by tightening the magnets 52, 54, which are sandwiched between the central yoke 62, via the upper and lower yokes 64, 66.

[0101] Furthermore, since the shaft 76 inserted into the movable body is pressed into and fixed to the sleeves 72 and 74, the movable body can be constructed by integrating the sleeves 72 and 74 with the magnetic material, and the movable body 60 and the elastic units 81 and 82 can be easily assembled.

[0102] In this embodiment, the sleeves 72 and 74 are formed to have the same shape, and the shaft 76 and the spring stop members 77 and 78 are fixed in the respective through holes 722 and 742 .

[0103] In this embodiment, the sleeves 72, 74 are press-fitted onto a shaft 76 that passes through the pair of magnets 52, 54, the central yoke 62, and the upper and lower yokes 64, 66, thereby sandwiching and fixing the pair of magnets 52, 54, the central yoke 62, and the upper and lower yokes 64, 66. The sleeves 72, 74 may be fixed by adhesive bonding using, for example, a thermosetting adhesive such as epoxy resin or an anaerobic adhesive, in addition to press-fitting the shaft 76. The pair of magnets 52, 54, the central yoke 62, the upper and lower yokes 64, 66, and the shaft 76 may also be fixed by adhesive bonding using, for example, a thermosetting adhesive such as epoxy resin or an anaerobic adhesive.

[0104] Furthermore, because the sleeves 72 and 74 have the functions of fixing the movable body, serving as a weight, and fixing the spring, there is no need to assemble the components having each function separately. Simply providing the sleeves 72 and 74 in the movable body side magnetic circuit allows the elastic units 81 and 82, together with the weight, to be easily attached to the movable body 60, improving assembly efficiency.

[0105] <Elastic unit 80 (81, 82)> Figure 10 is a plan view of the elastic unit, Figure 11 is an exploded perspective view of the elastic unit, and Figures 12A, 12B and 12C are diagrams used to explain the spiral direction of the leaf spring of the elastic unit.

[0106] As shown in FIGS. 5 to 7, the elastic unit 80 (81, 82) supports the movable body 60 so that it can move back and forth in the vibration direction relative to a fixed body including the case 10 and the bobbin 40, etc.

[0107] The elastic units 81, 82 sandwich the movable body 60 in the vibration direction (axial direction) of the movable body 60, and are installed so as to intersect with the vibration direction on both the upper and lower ends of the movable body 60 and on both opening edge portions 452, 462, which are the upper and lower ends spaced apart in the axial direction of the bobbin 40. Each of the elastic units 81, 82 is formed in a plate shape and is formed so as to be freely displaceable between its outer periphery and inner periphery.

[0108] 5 to 7, the elastic units 81 and 82 are connected to the upper and lower ends of the movable body 60 at their inner peripheral portions 814, and are connected to the fixed body (bobbin 40) at their outer peripheral portions 815. In this embodiment, the elastic units 81 and 82 are spaced apart from each other in the vibration direction and are arranged opposite each other in a direction perpendicular to the vibration direction.

[0109] As shown in FIGS. 5 to 7 and 10 to 12, the elastic units 81 and 82 each include a pair of leaf springs 802 and 804, a frame-shaped spring holder 806 interposed between the pair of leaf springs 802 and 804, and spring stop members 77 and 78.

[0110] The elastic units 81, 82 are elastic units 80 that are similarly formed and have the same configuration, except for the different orientations of the spring stop members 77, 78 inserted into the through holes 812 and the positions of the annular collar portions 808, 810 that secure them. Therefore, in the following, the upper elastic unit 81 will be referred to as the elastic unit 80, and a description will be given with reference to the diagram of the elastic unit 81, and a description of the configuration of the lower elastic unit 82 will be omitted.

[0111] In this embodiment, the elastic unit 81 has a damping material 88, and the damping material 88 is arranged in the elastic unit 81. The elastic unit 81 is joined by inserting the spring stop members 77 and 78 into the through holes 812 in a state where the spring holder 806 is sandwiched between the pair of leaf springs 802 and 804.

[0112] The leaf springs 802, 804 are preferably elastically deformable (freely deformable) and made of a non-magnetic material. The leaf springs 802, 804 are formed, for example, by processing a non-magnetic metal plate such as SUS into a thin, flat, disc-shaped spiral spring. Because the elastic unit 81 is formed in a flat plate shape, it is possible to improve positional accuracy, i.e., improve processing accuracy, compared to a conical spring.

[0113] 10 and 11 , the leaf springs 802, 804 have a central annular inner peripheral portion 814 that forms the inner spring end, a frame-shaped outer peripheral portion 815 that forms the outer spring end, and a deformed arm portion 816 that is arc-shaped in plan view and is interposed between the inner peripheral portion 814 and the outer peripheral portion 815. Note that leaf springs 802, 804 of similar shapes may be used. If the elastic unit 80 is constructed using two leaf springs 802, 804 that have the same configuration, the number of parts can be reduced, thereby reducing product costs.

[0114] The outer circumferential portion 815 is disposed radially outward of the inner circumferential portion 814 (outward of the inner circumferential portion 814 in a direction perpendicular to the axial direction).

[0115] The leaf springs 802, 804 are fixed at the outer periphery 815 inside the case 10 by a resin spring holder 806, a resin bobbin 40, and end spacers 22, 24, and the movable body 60 is positioned so as not to come into contact with the inner surface of the bobbin 40.

[0116] The leaf springs 802 and 804 have two deformed arm portions 816, and as shown in FIG. 12A, the spiral directions of the leaf springs 802 and 804 are arranged in opposite directions (in the direction of the arrows in FIGS. 12B and 12C) with the spring holder 806 in between.

[0117] When the leaf springs 802 and 804 deform together in the axial direction, they deform in different torsional directions, which are different from the translational direction (here, the direction of circumferential movement on a plane perpendicular to the vibration direction). The circumferential movements of the deforming leaf springs 802 and 804 (mainly the deforming arm portion 816) cancel each other out, and each elastic unit 81 (80) does not move in the twisting direction (circumferential direction) when moving in the axial direction.

[0118] The leaf springs 802 and 804 are formed with notches 817 that engage with the protrusions 807 of the spring holder 806. The protrusions 807 are engaged with the notches 817, and the spring holder 806 is positioned between the outer peripheries 815 of the leaf springs 802 and 804, so that the leaf springs 802 and 804 are positioned to sandwich the spring holder 806 while ensuring their deformation range.

[0119] Damping material 88 is disposed on leaf springs 802 and 804. Damping material 88 suppresses the resonance peak of the resonant vibration. As shown in FIG. 10 , damping material 88 is attached so as to bridge between outer peripheral portion 815 and deformable arm portion 816. Damping material 88 is disposed on both leaf springs 802 and 804 in the same manner.

[0120] The spring holder 806 is formed in a frame shape surrounding the deformation regions of the leaf springs 802, 804, and abuts on its front and back surfaces against the outer periphery 815 of the leaf springs 802, 804. The spring holder 806 also functions as a spacer that provides a space between the pair of leaf springs 802, 804 to allow deformation, and can hold the pair of leaf springs 802, 804 in a spaced-apart state. The spring holder 806 is preferably fixed to the outer periphery 815 of the leaf springs 802, 804 on its front and back surfaces. Protrusions 807, 809 are provided on the front and back surfaces of the spring holder 806 (surfaces separated by the outer periphery 815).

[0121] The protrusions 807 and 809 are appropriately engaged with the notch 817 and the notches 4522 and 4622 of the opening edges 452 and 462 to position them relative to each other.

[0122] The leaf springs 802, 804 are fixed by an annular collar portion 808 arranged between the leaf springs 802, 804 inside the spring holder 806, a collar portion 810 arranged adjacent to the outside of the leaf spring 804, and a spring stop member 77 (78) that passes through these collar portions 808, 810.

[0123] The spring stop members 77, 78 are inserted into the through holes 812 of the elastic units 81, 82 to fix the elastic units 81, 82 to the movable body 60 (specifically, the sleeves 72, 74). Rivets or the like may be used as the spring stop members 77, 78.

[0124] In this embodiment, the spring stop members 77, 78 are formed in the same shape, and have axial insertion portions 772, 782 and flanges 774, 784 provided on the edges of one ends of the insertion portions 772, 782. The spring stop members 77, 78 are made of a non-magnetic material, such as copper.

[0125] The insertion portions 772, 782 are inserted through the through-holes (through-holes 812) of the elastic units 81, 82 and the collar portions 808, 810, respectively, and are fixed in an inserted state in the through-holes 722, 742 of the sleeves 72, 74. The insertion portions 772, 782 are fixed by press-fitting into the through-holes 722, 742. The insertion portions 772, 782 may be fitted into the collar portions 808, 810, whereby the leaf springs sandwiched between the collar portions 808, 810 are fixed to the insertion portions 772, 782.

[0126] The collar portions 808 and 810 are made of a non-magnetic material, such as copper. The collar portion 808 is disposed between the leaf springs 802 and 804 and maintains the spacing between inner circumferential portions 814 of the leaf springs 802 and 804. The spring stop members 77 and 78 are press-fitted into the collar portion 810, and the collar portion 810 is integrated with the leaf springs 802 and 804.

[0127] The flanges 774, 784 fix the inner peripheral portions of the elastic units 81, 82 (corresponding to the inner peripheral portion 814 of the leaf spring) in a sandwiched state together with the sleeves 72, 74. The insertion portions 772, 782 and the through holes 722, 742 may be joined by welding, adhesive, crimping, or the like, or by a combination of welding, adhesive, and crimping.

[0128] In this embodiment, each of the multiple elastic units 81, 82 uses multiple spiral-shaped leaf springs, which are attached to both ends of the movable body 60 that are spaced apart in the vibration direction, thereby elastically supporting the movable body 60 relative to the fixed body (bobbin 40).

[0129] The elastic units 81, 82 of this embodiment are arranged with the spiral directions of each elastic unit 81, 82 facing in different directions and are fixed to the movable body 60. This allows the elastic units 81, 82 to move the movable body 60 straight in the axial direction (vibration direction), and enables the generation of an appropriately increased vibration output.

[0130] If the spiral directions of the leaf springs 802, 804 supporting the movable body from above and below are all in the same direction, when the movement of the movable body 60 increases, the movable body moves in the translational direction while rotating slightly. In contrast, in each of the elastic units 81, 82 of this embodiment, the leaf springs 802, 804 are arranged so that the spiral directions of the leaf springs 802, 804 are opposite to each other. As a result, the rotational movements of the leaf springs 802, 804 cancel each other out, and when the inner peripheral portion moves in the axial direction, it is less likely to rotate and moves straight in the axial direction.

[0131] The damping material 88 damps vibrations generated in the leaf springs 802 and 804. The damping material 88 damps sharp spring resonances in the leaf springs 802 and 804, and prevents large differences in vibration due to frequency, for example, in the entire elastic unit 81 (80), which may occur when vibrations near the resonance frequency become significantly large.

[0132] This allows the movable body 60 to suppress resonance peaks before plastic deformation, and allows stable vibrations to be generated over a wide range between the bottom surface 124 of the case 10 and the bracket 14 without contacting either of them, preventing abnormal noise due to contact. The damping material 88 may be formed in any shape or from any material, etc., as long as it prevents sharp vibrations from occurring in the leaf springs 802, 804. The damping material 88 may be applied to the leaf springs 802, 804, so that it is disposed without being fixed to each of the leaf springs 802, 804.

[0133] In the elastic unit 81 (80), two leaf springs 802, 804 are deformed at the upper and lower ends of the movable body 60, thereby supporting the movable body 60 so that it can move axially.

[0134] When the elastic units 81 (80) are attached to the opening edge portions 452, 462 of the coil assembly 26, the outer peripheries 815 of the leaf springs 802, 804 are clamped in the axial direction by the opening edge portions 452, 462, the spring holder 806, and the end spacers 22, 24.

[0135] Meanwhile, the inner circumferential portions of the elastic unit 81 (80) (portions corresponding to the inner circumferential portions 814 of the leaf springs 802, 804) are fixed to the upper and lower ends of the movable body 60 (ends of the sleeves 72, 74) via the spring stop members 77, 78. As a result, the elastic unit 81 (80) is bridged between the opening edge portions 452, 462 and the upper and lower ends of the movable body 60 (ends of the sleeves 72, 74) so ​​as to be perpendicular to the axial direction.

[0136] The deforming arm portion 816 and inner circumferential portion 814 of the elastic unit 81 are arranged within a movable area that is freely movable in the axial direction, and the deforming arm portion 816 and inner circumferential portion 814 of the elastic unit 82 are arranged within a movable area that is freely movable in the axial direction.

[0137] The elastic unit 81 (80) is clamped within the case 10 between the end faces of the upper and lower opening edge portions 452, 462 of the coil assembly 26 (bobbin 40) and the end spacers 22, 24, and is arranged along a direction perpendicular to the vibration direction.

[0138] In the vibration actuator 1, the actuator unit 20 is covered by a magnetic case 10. This allows for a configuration in which only the central portion of the movable body 60 (magnets 52, 54, central yoke 62, upper and lower yokes 64, 66) is magnetic, making it possible to reduce leakage magnetic flux and the number of parts without using a separate magnetic shielding material to surround the magnetic parts, thereby maximizing the number of internal parts.

[0139] The elastic units 81 and 82 each use a pair of leaf springs 802 and 804, with each leaf spring having two deforming arms 816. This means that, unlike a configuration in which the leaf spring requires three or more deforming arms 816, the deforming arms 816 of the leaf springs 802 and 804 can be lengthened to vibrate at a low resonance frequency even when the size is reduced.

[0140] The vibration actuator 1 has a structure in which two spiral leaf springs 802, 804 are arranged on one side (one axial side) of the movable body 60, making it possible to realize an actuator that is small but has leaf springs 802, 804 that are compatible with low resonance frequencies.

[0141] Furthermore, in the elastic units 81 and 82 of the vibration actuator 1, the damping materials 88B and 88C are sandwiched between two leaf springs 802 and 804, widening the contact area between the leaf springs 802 and 804 and the damping materials 88B and 88C. This allows the vibration actuator 1 to obtain a large damping effect (see FIG. 18) due to the damping materials 88B and 88C, and to output strong vibrations over a wide frequency band.

[0142] The elastic units 81 and 82 can be configured by combining two identical leaf springs 802 and 804 with the front and back reversed. This cancels out the torsional movement of the movable body 60 and the rotational movement of the springs when they expand and contract, thereby suppressing higher-order resonance.

[0143] The positions and spacing of the two spiral leaf springs 802, 804 are set by the spring stop members 77, 78, collar portions 808, 810, and spring holder 806. This allows them to be used as an integrated elastic unit, making assembly with the movable body 60 easy.

[0144] Since the magnets 52 and 54 are arranged with the same poles butted together, a thrust can be generated with a larger magnetic force even in a small size.

[0145] A magnetic circuit (three slots) is configured with three coils (center coil 32, upper coil 34, and lower coil 36) for the pair of magnets 52, 54. This reduces leakage of the generated magnetic force, enabling effective generation of magnetic force.

[0146] In the vibration actuator 1, the leaf springs 802, 804 in the elastic units 81, 82 may be provided in the same winding direction for each of the elastic units 81, 82.

[0147] That is, in the vibration actuator 1, each of the pair of leaf springs 802, 804 is a spiral spring having a deformation arm portion 816 suspended between an inner peripheral portion 814 and an outer peripheral portion 815, and each pair of elastic bodies is arranged with the same winding direction. In addition, each of the pair of elastic bodies 81, 82 is arranged with a different winding direction.

[0148] With this configuration, the elastic units 81 and 82 that sandwich the movable body 60 from above and below cancel out the torsional movement of the movable body 60 when it is driven and the rotational movement when the spring expands and contracts, thereby suppressing higher-order resonance.

[0149] <Modifications of Elastic Unit> In the elastic units 81, 82 of the vibration actuator 1 of embodiment 1, the damping material 88 is provided so as to be in contact with each of the leaf springs 802, 804, but it may also be sandwiched between the leaf springs 802, 804. Examples of this are shown as modifications in Figures 13A to 17.

[0150] Fig. 13A is an exploded perspective view of the elastic unit 80 according to Modification 1, and Fig. 13B is a vertical cross-sectional view of the elastic unit 80 according to Modification 1. Note that in Figs. 13A and 13B, Modification 1 of the elastic unit 80 is illustrated as a modification of the lower elastic unit 82.

[0151] Fig. 14 is a diagram showing a second modified example of the elastic unit, Fig. 15 is an exploded perspective view of the second modified example of the elastic unit, Fig. 16 is a diagram showing a third modified example of the elastic unit, and Fig. 17 is an exploded perspective view of the third modified example of the elastic unit.

[0152] In the elastic unit 82A as modified example 1 shown in Figures 13A and 13B, in the configuration of the elastic unit 82, a damping material 88A having an opening 882 is arranged within the spring holder 806 between a pair of leaf springs 802, 804 that sandwich the spring holder 806.

[0153] The damping material 88A is disposed between the leaf springs 802 and 804 so as to surround the periphery of the collar portion 808. The damping material 88A abuts against both the leaf springs 802 and 804 and is disposed so as to be in contact with both the leaf springs 802 and 804 without being fixed thereto.

[0154] The damping material 88A is in the shape of a circular plate, and is sandwiched between two spiral leaf springs 802, 804, so that the annular surfaces of the damping material 88A contact the leaf springs 802, 804 on both the front and back sides, thereby increasing the contact area with the leaf springs 802, 804.

[0155] This provides a strong damping effect, enabling strong vibrations even in the high frequency band. By adjusting the heights of the collars 808, 810 and the spring holder 806 to generate deflection in the leaf springs 802, 804 and sandwich the damping material 88A, the damping material can be fixed without using adhesive. Furthermore, the damping material 88A is compressed by the leaf springs 802, 804, resulting in surface contact, providing a strong damping effect.

[0156] Furthermore, as a configuration in which damping material is sandwiched between the leaf springs 802, 804, a configuration in which a plurality of damping materials 88B, 88C are sandwiched may be used, as shown in elastic units 81B, 81C in Figures 14 to 17. In elastic unit 81B shown in Figures 14 and 15, the plurality of damping materials 88B are arranged near the connection between outer peripheries 815 of the leaf springs 802, 804 and deformable arm portions 816.

[0157] On the other hand, in the elastic unit 81C shown in FIGS. 16 and 17, a plurality of damping materials 88C are arranged between the outer periphery 815 of the leaf springs 802 and 804 and the center of the deforming arm portion 816.

[0158] 14 to 17, the damping materials 88B and 88C are held in place by interposing adhesive or double-sided adhesive tape between their side surfaces and the inner side surfaces of the spring holder 806. No adhesive or double-sided adhesive tape is interposed between the damping materials 88B and 88C and the leaf springs 802 and 804; that is, they are in contact with each other without being joined. In other words, the damping materials 88B and 88C are arranged in the elastic units 81B and 81C in contact with the leaf springs 802 and 804 without being fixed thereto.

[0159] In this way, in elastic unit 81 (similar to elastic unit 82), by changing the position at which damping materials 88B and 88C contact leaf springs 802 and 804 and adjusting the contact area, it is possible to provide suitable vibration damping for leaf springs 802 and 804.

[0160] <Operation of Vibration Actuator 1> In vibration actuator 1, surfaces 52a and 54a of magnet 50 (52, 54) that face each other in the magnetization direction have the same magnetic polarity (north poles or south poles). In addition, surfaces 52a and 54a of the pair of magnets 52 and 54 with the same magnetic polarity sandwich a central yoke 62, and upper and lower yokes 64 and 66 are respectively positioned in contact with the back surfaces of the pair of magnets 52 and 54, thereby constituting the magnetic body of movable body 60.

[0161] In the vibration actuator 1, the movable body 60 is considered to correspond to the mass part in a vibration model of a spring-mass system, so when the resonance is sharp (has a steep peak), the steep peak is suppressed by damping the vibration.

[0162] FIG. 18 is a diagram showing the vibration characteristics of the vibration actuator according to the first embodiment. As shown by the vibration characteristic G1 in FIG. 18, in the vibration actuator 1, by damping the vibration using the damping materials 88, 88A, 88B, 88C, etc., the resonance peak p1 is reduced and the resonance vibration characteristics are not as steep. This prevents variations in the maximum amplitude value and maximum movement amount of the movable body 60 during resonance within a wide frequency band, even at high frequencies, and allows a high G value (impact value, vibration intensity) to be obtained. The actuator unit 20 can be caused to output vibrations with an appropriate, stable maximum movement amount. The vibration actuator 1 can lower the resonance frequency f0, for example, to 20-500 Hz, and can generate appropriate vibrations even at high frequencies.

[0163] Fig. 19 is a diagram schematically showing the magnetic circuit of the vibration actuator according to the first embodiment. In the vibration actuator 1, the magnetic circuit shown in Fig. 19 is formed. In Fig. 19, surfaces 52a, 54a of a pair of magnets 52, 54 are designated as north pole faces. Furthermore, in the vibration actuator 1, the coil axis of the coil 30 (32, 34, 36) is arranged so as to be perpendicular to the flow of magnetic flux that flows from the central yoke 62, which sandwiches the magnets 52, 54 in the vibration direction, to the central coil 32.

[0164] Specifically, the magnetic flux is emitted from the surface side of the pair of magnets 52, 54, passes through the central yoke 62, and is radiated in a radial direction perpendicular to the axial direction toward the central coil 32. The magnetic flux radiated from the outer periphery of the central yoke 62 to the central coil 32 passes through the peripheral wall portion 122 of the case 10, which is made of a magnetic material, and enters the upper and lower yokes 64, 66 via the upper and lower coils 34, 36. The magnetic flux is then incident on the magnets 52, 54 from the upper and lower yokes 64, 66.

[0165] In this manner, in the vibration actuator 1, a magnetic flux flow mf is formed in the order of the pair of magnets 52, 54, central yoke 62, central coil 32, peripheral wall portion 122, upper and lower coils 34, 36, upper and lower yokes 64, 66, and magnets 52, 54.

[0166] 19, when current is applied, the magnetic field of the magnets 52, 54 interacts with the current flowing through the coil 30 (32, 34, 36), generating a Lorentz force in the -f direction in the coil 30 (32, 34, 36) according to Fleming's left-hand rule. Because the coil 30 (32, 34, 36) is fixed to the fixed body (bobbin 40), a force opposite to this Lorentz force in the -f direction is generated in the movable body 60 having the magnets 52, 54 as a thrust in the F direction, according to the law of action and reaction. As a result, the movable body 60 having the magnets 52, 54 moves in the F direction, i.e., toward the bracket 14.

[0167] Furthermore, when the direction of current flow in the coils 30 (32, 34, 36) is reversed and current is passed through the coils 30 (32, 34, 36), a Lorentz force is generated in the opposite direction, f-direction. Due to the generation of this Lorentz force in the f-direction, in accordance with the law of action and reaction, a force opposite to the Lorentz force in the f-direction is generated as a thrust (thrust in the -F direction) on the movable body 60, and the movable body 60 moves in the -F direction, i.e., toward the bottom surface 124 of the fixed body (bobbin 40).

[0168] In the vibration actuator 1, when not energized and not driven (not vibrating), the movable body 60 returns to its original position due to the magnetic spring function caused by the magnetic attraction force generated between the magnets 52, 54 and the case 10, and the restoring force of the elastic units 81, 82.

[0169] In the vibration actuator 1, the magnetic circuit including the magnets 52, 54, the central coil 32, and the upper and lower coils 34, 36 is surrounded on its outer periphery by a case 10 which functions as an electromagnetic shield.

[0170] In this way, the vibration actuator 1 has shock resistance and can output a suitable bodily vibration with high vibration expression.

[0171] The vibration actuator 1 is driven by an AC wave input to the coils 30 (32, 34, 36) from a power supply unit (for example, the drive control unit 203 shown in FIGS. 70 and 71). In other words, the direction of current flow through the coils 32, 34, 36 switches periodically, and a thrust in the F direction on the bracket 14 side and a thrust in the -F direction on the bottom surface portion 124 side act alternately on the movable body 60. This causes the movable body 60 to vibrate.

[0172] Here, we will briefly explain the driving principle of the vibration actuator 1. In the vibration actuator 1 of this embodiment, the mass of the movable body 60 is m [kg], the spring constant of the springs (leaf springs 802, 804) is K ｓｐ In this case, the movable body 60 has a resonance frequency F ｒ It vibrates at [Hz].

[0173]

[0174] Since the movable body 60 is considered to constitute a mass part in a vibration model of a spring-mass system, the resonance frequency F of the movable body 60 is applied to the coil 30 (32, 34, 36). ｒ When an AC wave having a frequency equal to the resonant frequency F of the movable body 60 is input, the movable body 60 enters a resonant state. ｒ By inputting an AC wave having a frequency substantially equal to the frequency of the movable body 60, the movable body 60 can be vibrated efficiently.

[0175] Below are shown the equation of motion and the circuit equation that show the driving principle of the vibration actuator 1. The vibration actuator 1 is driven based on the equation of motion shown in the following equation (2) and the circuit equation shown in the following equation (3).

[0176]

[0177]

[0178] That is, the mass m [kg], displacement x(t) [m], thrust constant K f [N / A], current i(t) [A], spring constant K sp [N / m], damping coefficient D [N / (m / s)], etc. can be changed as appropriate within the range that satisfies formula (2). ｅ [V / (rad / s)] can be changed as appropriate within a range that satisfies formula (3).

[0179] In this way, in the vibration actuator 1, the mass m of the movable body 60 and the spring constant K of the elastic units 81 and 82 (leaf springs) ｓｐ The resonant frequency F is determined by ｒ When the coil 30 (32, 34, 36) is energized with an AC wave corresponding to the above, a large vibration output can be obtained efficiently.

[0180] Furthermore, the vibration actuator 1 satisfies equations (2) and (3) and is driven by a resonance phenomenon using the resonance frequency shown in equation (1). As a result, the only power consumed in the vibration actuator 1 in a steady state is the loss due to the damping material 88, allowing it to be driven with low power consumption, i.e., the movable body 60 to move back and forth linearly (vibrate) with low power consumption. Furthermore, by increasing the damping coefficient D, it is possible to generate vibrations over a wide frequency range.

[0181] The vibration actuator 1 has a rectangular parallelepiped shape, and the movable body 60 also has a rectangular parallelepiped shape. This structure has a larger volume than a cylindrical actuator of the same diameter, so when placed in a similar space, the space can be fully utilized to form a more effective magnetic circuit.

[0182] <Embodiment 2> Fig. 20 is a longitudinal sectional view of a vibration actuator according to embodiment 2, and Fig. 21 is a perspective view showing a movable body with an elastic unit removed in the vibration actuator according to embodiment 2. Also, Fig. 22 is an exploded perspective view of the movable body in the vibration actuator according to embodiment 2.

[0183] The vibration actuator 100 of the second embodiment differs from the vibration actuator 1 of the first embodiment in the configuration of the movable body 600, but the other components are similar in configuration and function to each other. Therefore, only the different components will be described below, and similar components will be given the same names and symbols and will not be described again.

[0184] 19 to 21 has a hollow case 10, and an actuator unit 20a housed in the hollow case 10 together with end spacers 22, 24. The actuator unit 20a has a coil assembly 26 as a fixed body having a coil 30, a movable body 600 housed within the coil assembly 26 and having a magnet 50, and elastic units 81, 82 that support the movable body 600 so that it can move freely.

[0185] In the actuator unit 20a, the coil assembly 26 and the elastic units 81 and 82 have the same configuration as the actuator unit 20, and only the configuration of the movable body 600 is different.

[0186] The movable body 600 includes a magnet 50 (52, 54), a central yoke 62, upper and lower yokes 640, 660, sleeves 720, 740, a shaft 76, and spring stop members 77, 78.

[0187] In the movable body 600, similarly to the movable body 60, the shaft 76 is inserted, and the pair of magnets 52, 54 are arranged with the same magnetic pole faces (surfaces 52 a, 54 a) facing each other across the central yoke 62. Additionally, in the movable body 600, upper and lower yokes 640, 660 are arranged adjacent to the pair of magnets 52, 54 on the axially outer side, respectively.

[0188] The upper and lower yokes 640, 660 are formed with openings 6420, 6620 that are larger than the outer diameter of the shaft 76 and penetrate the yokes in the axial direction. One end of the sleeves 720, 740 is inserted and fitted into the openings 6420, 6620.

[0189] One end of the sleeve 720, 740 faces the magnet 52, 54 and is fixed in contact with the magnet 52, 54 together with the upper and lower yokes 640, 660. Note that the one end of the sleeve 720, 740 does not have to be in contact with the magnet 52, 54 as long as it is configured to be fixed within the openings 6420, 6620. The spring stop members 77, 78 of the elastic units 81, 82 are inserted into the through holes (through portions) 702, 704 of the sleeve 720, 740, together with the shaft 76. The sleeve 720, 740 may be fixed by being press-fitted into the upper and lower yokes 640, 660.

[0190] As a result, in the vibration actuator 100, the movable body 600 can connect the sleeves 720, 740 to the elastic units 81, 82 on the axially outer side of the upper and lower yokes 640, 660 without coming into full contact with them. In other words, as shown in Figure 20, the upper surface 640a of the upper yoke 640 is configured to face the leaf spring 804, and no sleeve is disposed on the upper surface 640a. This makes it possible to reduce the weight of the sleeve disposed on the upper surface 640a, and also reduces the weight of the ends in the axial direction.

[0191] (Embodiment 3) [Configuration of Vibration Actuator] Fig. 23 is an external perspective view of a vibration actuator according to this embodiment 3 as seen from the front side, and Fig. 24 is a plan view of the same vibration actuator. Fig. 25 is a cross-sectional perspective view taken along line B-B in Fig. 24, and Fig. 26 is an exploded perspective view of the same vibration actuator with the case removed. Fig. 27 is a perspective view of the actuator unit with the end spacers removed, and Fig. 28 is an exploded perspective view of the actuator unit with the movable body removed. Fig. 25, along with Figs. 35 and 43, is a cross-sectional view in a perspective projection.

[0192] In the following description, the terms "upper" and "lower" in terms such as "upper side" and "lower side" are used for convenience to facilitate understanding of the configuration and behavior of the vibration actuator according to each embodiment. When the vibration actuator according to each embodiment is mounted on an electrical device (see FIGS. 70 and 71 ), the "upper" and "lower" described here may be reversed, may be rotated left and right, or may be diagonal. Incidentally, in each embodiment, the up-down direction is the vibration direction of the movable body in the vibration actuator 1D, with the "upward direction" being one of the vibration directions and the "downward direction" being the other of the vibration directions. In other words, the vibration actuator is a linear actuator that vibrates the movable body linearly in the up-down direction.

[0193] In the following description, unless otherwise specified, the term "radial direction" refers to a direction extending radially or centrifugally around the central axis CA, which extends in the up-down direction of the vibration actuator 1D. Furthermore, the terms "outside" and "inside" in terms such as "outside" and "inside" refer to the outward and inward directions in the radial direction around the central axis CA. Furthermore, unless otherwise specified, the term "circumferential direction" refers to a direction extending around the central axis CA.

[0194] The vibration actuator 1D according to the third embodiment is mounted as a vibration generating source (vibration actuator 206) in an electronic device such as a portable game terminal (for example, the game controller GC shown in FIG. 69 ), and realizes the vibration function of the electronic device. Such electronic devices also include portable devices such as smartphones (for example, the portable terminal M shown in FIG. 70 ). The vibration actuator 1D is mounted in a portable game terminal or other device, and vibrates when driven to notify the user of an incoming call or to provide a sense of operation or realism.

[0195] 23 to 26 , the vibration actuator 1D of this embodiment has a hollow case 10 and an actuator unit 20 that is housed in the hollow case 10 together with end spacers 22, 24. The actuator unit 20 has a coil assembly 26 that has a coil 30, a movable body 60 that is housed in the coil assembly 26 and has magnets 50 (52, 54), and an elastic unit (elastic body) 80 that movably supports the movable body 60. The coil assembly 26, together with the case 10 and the end spacers 22, 24, constitutes a fixed body.

[0196] <Case 10> In the vibration actuator 1D, the case 10 constitutes a fixed body together with the coil assembly 26 of the actuator unit 20.

[0197] The case 10 is formed so as to cover at least the periphery of the actuator unit 20, that is, so as to surround the actuator unit 20 in a direction perpendicular to the axial direction thereof.

[0198] The case 10 is made of a magnetic material and functions as a magnetic shield. The case 10 is formed of a cylindrical case body 12 with a bottom and an open end, and a magnetic metal (SECC, etc.) plate together with a bracket 14. If a magnetic shield is not required on the open side of the case body 12, the bracket 14 may be made of a non-magnetic material such as a non-magnetic metal or non-magnetic resin.

[0199] The case 10 has a cylindrical case body 12 with a bottom and a plate-like bracket 14 that closes the opening of the case body 12 .

[0200] The case body 12 surrounds the outer peripheral surface of the bobbin 40 of the actuator unit 20 and includes a rectangular cylindrical magnetic body that is positioned to cover the radially outer side of the central coil 32 and the upper and lower coils 34, 36. The actuator unit 20 is housed within the case body 12, and a bracket 14 is placed on the actuator unit 20 within the case body 12 to close the opening of the case body 12.

[0201] The case body 12 is configured by covering one opening of a rectangular cylindrical peripheral wall portion 122 with a bottom portion 124 .

[0202] The bracket 14 closes the opening of the case body 12 and corresponds to the shape of one surface (top surface) of the actuator unit 20 .

[0203] The bracket 14 has a shape that engages with the terminal lead-out portion 47 of the actuator unit 20 by cutting two corners of the rectangular plate-like body.

[0204] A conductive board 16 is disposed on the upper part of the bracket 14. The conductive board 16 is connected to a connection terminal 48 in a terminal lead-out portion 47 that protrudes from a corner of the bracket 14, and supplies power to the coil 30.

[0205] The case 10 covers the central coil 32, upper and lower coils 34, 36, magnets 52, 54, central yoke (first yoke) 62, and upper and lower yokes (second yokes) 64, 66, and prevents magnetic flux from leaking outside the vibration actuator 1D.

[0206] In the case 10, the bracket 14 and the bottom surface portion 124 are each a movement range restricting portion having a hard stop (movement range limiting) function that restricts the movement range of the movable body 60. The bracket 14 and the bottom surface portion 124 each prevent the movable body 60 from receiving an external impact and moving within a movement range larger than the normal vibration range. Specifically, the bracket 14 and the bottom surface portion 124 restrict the length to the elastic units 81, 82 attached to the upper and lower ends of the actuator unit 20 (coil assembly 26).

[0207] <Actuator Unit 20> The actuator unit 20 is formed in a cylindrical shape and is housed in the case 10 with end spacers 22, 24 engaged with openings at both ends (upper and lower ends) spaced apart in the axial direction.

[0208] The actuator unit 20 has a cylindrical coil assembly 26 as a fixed body, a movable body 60 having a magnet and a yoke, and a pair of elastic units 81 and 82 .

[0209] In the actuator unit 20, the coil 30 and the magnet form a magnetic circuit that vibrates the movable body 60. The magnetic circuit does not necessarily require a yoke. When electricity is applied to the coil 30 from a power supply unit (which may be a drive board), the coil 30, magnet, and yoke work together to cause the movable body 60 to reciprocate in the vibration direction inside the coil assembly 26 in the case 10.

[0210] <Coil assembly 26> The coil assembly 26 is a cylindrical body having a coil 30 and a bobbin 40. The coil assembly 26 supports the movable body 60 within the coil assembly 26 via an elastic unit 80, and accommodates the movable body 60 so that it can freely move back and forth in the axial direction (vibration direction). The coil assembly 26 is formed in a square cylindrical shape, for example, a rectangular cylindrical shape. In this case, the coil 30 and the bobbin 40 are also formed in a rectangular cylindrical shape. The coil assembly 26 (coil 30, bobbin 40) and the movable body 60 have an outer shape that is rectangular parallelepiped or cubic. These may also be formed in a polygonal shape.

[0211] <Coils 30 (central coil 32, upper and lower coils 34, 36)> The coils 30 (32, 34, 36) are configured in a number corresponding to the number of magnets 50, and are held on the bobbin in a state where they are concentrically arranged around the central axis CA and juxtaposed along the direction of the central axis CA (corresponding to the "axial direction", which in this embodiment is the same direction as the up and down direction).

[0212] The coil 30 is arranged spaced apart in a direction perpendicular to the axial direction on the outer peripheral surface of the central portion of a movable body having a pair of magnets 50 (52, 54). In the vibration actuator 1D, the coil 30, together with the magnets 50 (52, 54) and yokes (62, 64, 66), vibrates in the axial direction of the coil 30 (32, 34, 36) (the magnetization direction of the magnet 50).

[0213] The coil 30 has a central coil 32 arranged in a position surrounding the axial center of the pair of magnets, and a pair of upper and lower coils 34, 36 arranged on both axial sides of the central coil 32. For convenience, the coil 30 is also referred to as coil 30 (32, 34, 36). When driven (vibrating), the coils 30 (32, 34, 36) are energized and constitute a voice coil motor together with the magnets 50 (52, 54) and yokes (62, 64, 66).

[0214] Preferably, the central coil 32 and the upper and lower coils 34, 36 have the same outer shape, the central coil 32 has the longest vertical length, and the upper and lower coils 34, 36 have the same vertical length.

[0215] The vertical length of the central coil 32 is a length that falls within the range of movement of the vertical center position of the movable body 60, that is, the vertical center position between the pair of magnets 50 (52, 54). In other words, when the movable body 60 moves, the vertical center position of the movable body 60 (for example, the center position of the central yoke) is a length that falls within the vertical range of the upper and lower coils 34, 36.

[0216] The central coil 32 is disposed opposite to the central position of the movable body 60 having a pair of magnets 50 (52, 54) that constitutes a circuit with the highest magnetic efficiency of the movable body 60.

[0217] The upper and lower coils 34 and 36 are arranged at positions symmetrical in the up and down direction with respect to the middle position of the range of motion determined by the maximum amplitude of the up and down movement of the movable body 60 .

[0218] The central coil 32 and the upper and lower coils 34, 36 are wired so that when current is applied, the movable body 60 moves linearly back and forth in the axial direction. The width of the central coil 32 is positioned within the movable range of the central yoke 62.

[0219] The central coil 32 and the upper and lower coils 34, 36 are configured so that current flows in opposite directions. For example, the central coil 32 and the upper and lower coils 34, 36 may be configured from a single coil wire, in which case the central coil 32 and the upper and lower coils 34, 36 are configured so that the coil wire is wound in opposite directions, and the coil wire is wound in the same direction in the upper and lower coils 34, 36. In other words, the central coil 32 and the upper and lower coils 34, 36 are configured so that current flows in opposite directions when energized.

[0220] Furthermore, when the central coil 32 and the upper and lower coils 34, 36 are configured from a single coil wire, the coil connection portion corresponding to the portion where the central coil 32 and the upper and lower coils 34, 36 are connected to each other is arranged across multiple intermediate flanges 43, 44 of the bobbin.

[0221] In addition, both ends of the wires of the upper and lower coils 34, 36, which correspond to the portions opposite to the portion connected to the central coil 32, are respectively connected to connection terminals 48 in the terminal lead-out portion 47 from the upper flange 45 that separates the upper coil 34.

[0222] 29 is a perspective, half-sectional view showing the configuration of the coil assembly. In the coil assembly 26, one end (both wire ends) of each of the upper and lower coils 34, 36 is connected to a power supply via a connection terminal 48 of a terminal lead-out portion 47. For example, each end of the coil 30 (32, 34, 36) is connected to an AC supply, and AC power (AC voltage) is supplied from the AC supply to the coil 30 via a conductive board 16. This separates the coil 30 (32, 34, 36) from the magnet 50 (52, 54) and the yoke (62, 64, 66), generating thrust that allows axial movement.

[0223] The coil axis of the coil 30 (32, 34, 36) is preferably arranged coaxially with the axis of the bobbin 40 or the axis of the magnet 50 (52, 54).

[0224] If the coils 30 (32, 34, 36) are configured to be formed by winding a coil wire around the bobbin 40, the coils 30 (32, 34, 36) can be assembled without using self-bonding wire. In other words, there is no need to use air-core coils as the coils 30 (32, 34, 36), which reduces the cost of the coils themselves and ultimately the cost of the entire vibration actuator.

[0225] Figure 30 is a plan view showing the positional relationship between the ribs and the movable body in the actuator unit, and Figure 31 is a plan view of the bobbin in Figure 30. The bobbin 40 holds the coil 30 (32, 34, 36) wound around its outer circumferential surface, and the inner circumferential surface 42a of the bobbin body 42, which is a central cylindrical body that is the bobbin body, surrounds the yoke. In addition, the bobbin guides the movement of the movable body 60 having the magnet 50 (52, 54) by means of ribs (regulating protrusions) 420 on the inner circumferential surface 42a.

[0226] The inner surface 42a of the bobbin 40 covers the inner surfaces of the coil 30 (central coil 32, upper and lower coils 34, 36) (see Figure 29), and functions as a protective wall that protects the central coil 32 and upper and lower coils 34, 36 from direct contact or collision with the movable body 60.

[0227] The inner peripheral surface 42a has four faces positioned in a rectangular cylindrical shape. Ribs 420 are provided on the inner peripheral surface 42a and extend in the axial direction.

[0228] The rib 420 slides against the movable body 60 that moves inside the inner circumferential surface 42a, and guides the movable body 60 in a suitable vibration direction, for example, along the axis of the bobbin 40 or along the penetration direction of the opening of the bobbin 40. One rib 420 may be provided on one side of the inner circumferential surface 42a, but it is preferable to provide multiple ribs on one side of the inner circumferential surface 42a.

[0229] As shown in FIG. 31, a plurality of ribs 420 are formed on the inner peripheral surface 42a of the bobbin 40 at positions that are point-symmetric with respect to the coil axis.

[0230] For example, two ribs 420 are arranged as protrusions on each of the four sides of the inner peripheral surface 42a.

[0231] The ribs 420 have their tips in line or point contact with the outer circumferential surface 60a of the moving movable body 60. The outer circumferential surface 60a of the movable body may be coated with a material to ensure smooth sliding, improved strength, and effective magnetic flux flow. For example, the outer circumferential surface 60a may be coated with nickel plating or the like.

[0232] The ribs 420 are configured so that their cross sections become smaller from the inner circumferential surface side toward the tip end of the bobbin 40. The ribs 420 have, for example, a semicircular cross section and are provided so as to extend in the axial direction.

[0233] The tips of the ribs 420 are provided on the inner peripheral surface 42a so as to protrude to the same degree.

[0234] Fig. 32 is a plan view showing a modified example of the actuator unit. As shown by the box X in Fig. 32, the ribs 420 may be configured so that only some of the ribs 420 on one side of the inner circumferential surface 42a slide on part of the inner circumferential surface 42a.

[0235] The bobbin 40 is a cylindrical body made of a non-magnetic and non-conductive resin material such as phenolic resin, polybutylene terephthalate (PBT), etc. In this embodiment, the bobbin is made of a material containing phenolic resin, such as Bakelite, which has high flame retardancy.

[0236] The bobbin 40 is made of a material containing phenolic resin, which increases its flame resistance and prevents deformation due to heat generation caused by Joule heat when a current flows through the coil 30 it holds, improving safety during operation. In addition, the dimensional accuracy of the bobbin 40 is improved, which increases the positional accuracy of the coil 30 and reduces variations in vibration characteristics.

[0237] The bobbin 40 has recesses 40a, 40b, and 40c that open in the circumferential direction and in which the central coil 32 and the upper and lower coils 34, 36 are arranged, on the outer periphery of a cylindrical bobbin body 42. The recesses 40a, 40b, and 40c are formed by the outer periphery of the bobbin body 42, a plurality of intermediate flanges 43, 44 that protrude radially from the outer periphery, and upper and lower flanges 45, 46 at both ends that define the movable range of the movable body 60.

[0238] The central coil 32, upper coil 34, and lower coil 36 are respectively arranged in recesses 40a, 40b, and 40c on the outer periphery of the bobbin body 42. The coils 30 (32, 34, and 36) are coaxial (coil axes) and are arranged in positions facing the yokes 62, 64, and 66 of the movable body 60, with the bobbin body 42 interposed therebetween, in a direction perpendicular to the axial direction.

[0239] The inner peripheral surface 42a of the bobbin body 42 is disposed opposite the outer peripheral surface 60a of the movable body 60 at a predetermined distance. This predetermined distance allows the movable body 60 to move in the axial direction, which is the vibration direction, without coming into contact with the inner peripheral surface 42a. The bobbin body 42 is configured to inhibit contact between the magnets 50 (52, 54) 30 and the coils 30 (32, 34, 36), and the movable body 60 can move back and forth along the inner peripheral surface 42a without coming into contact with the inner peripheral surface 42a.

[0240] The bobbin body 42 functions as a protective wall that protects the coils 30 (32, 34, 36) from collisions when the movable body 60 arranged inside is driven. The thickness of the bobbin body 42 is set to a thickness that provides strength such that the outer coils 30 (32, 34, 36) are not affected even when the moving movable body 60 comes into contact with the bobbin body 42.

[0241] The intermediate flanges 43, 44 are disposed at positions sandwiching the central coil 32. The intermediate flanges 43, 44 are formed with cutouts 432, 442, respectively, and coil connecting portions that connect the coils 30 (32, 34, 36) are disposed therein.

[0242] The upper and lower flanges 45, 46 are formed to protrude radially from both opening edges of the bobbin body 42, and have cylindrical opening edges 452, 462 that rise axially from the tips of the upper and lower flanges 45, 46.

[0243] The opening edges 452, 462 constitute both ends of the bobbin 40 that are spaced apart in the axial direction of the bobbin body 42 (which is the vibration direction and also the up-down direction in this embodiment).

[0244] Elastic units 80 (81, 82) are connected to the opening edge portions 452, 462, respectively. As a result, the elastic units 80 (upper elastic unit 81 and lower elastic unit 82) are connected to both ends (upper and lower ends in this embodiment) of the movable body 60 formed by the upper and lower flanges 45, 46.

[0245] The opening edge portions 452 and 462 are arranged so as to surround the central opening 400 of the bobbin body 42, and are formed in the shape of a rectangular frame with an outer shape larger than that of the central opening 400.

[0246] The opening shape of the opening edge portions 452, 462 is formed into a shape that abuts against and supports the outer periphery of the elastic unit 80, and engages with the elastic unit 80. The opening edge portions 452, 462 have cutout portions 4522, 4622 that engage with the protrusions 807, 809 of the elastic unit 80, and the protrusions 809, 807 engage with the cutout portions 4522, 4622 to position and fix the elastic unit 80. The inner periphery surfaces of the opening edge portions 452, 462 are inclined, and form a movable area for the elastic unit 80 (81, 82).

[0247] The upper and lower flanges 45, 46, together with the end spacers 22, 24, are positioned to sandwich the elastic unit 80, and form a deformation region in the vibration direction (vertical and axial direction) of the elastic unit 80, i.e., a movable range of the movable body 60. The movable range is formed at both axial ends within the case 10 by the internal space of the opening edge portions 452, 462, the end spacers 22, 24, the bottom surface portion 124 of the case main body 12, and the bracket 14.

[0248] Terminal lead-out portions 47 protrude in the axial direction from some of the corners of opening edge portion 452. Leg portions 480 of the same shape as terminal lead-out portions 47 are provided on opening edge portion 462 at positions corresponding to terminal lead-out portions 47 of opening edge portion 452, so as to protrude in a similar manner.

[0249] The end spacers 22, 24 are arranged on both ends of the actuator unit 20 via the elastic units 80. The end spacers 22, 24 are arranged to separate the elastic units 80 from the bottom surface 124 of the case 10 and the bracket 14. The end spacers 22, 24 accommodate the actuator unit 20 in the case 10 in a state where movement is restricted.

[0250] The end spacers 22, 24 are frame-like bodies formed to correspond to the shape of the elastic units 80 (81, 82) arranged at both ends of the actuator unit 20, and a central opening ensures a deformation area for the elastic units 80. The end spacers 22, 24 are of the same shape and have inclined sides 23 with which the terminal lead-out portion 47 and the leg portion 480 respectively engage.

[0251] The end spacers 22 and 24 are arranged at both ends of the actuator unit 20 by engaging the terminal lead-out portion 47 or the leg portion 480 with the inclined side portion 23 , and form a rectangular parallelepiped that is accommodated in the case 10 as a whole.

[0252] The end spacers 22, 24 ensure a deformation area for the elastic unit 80 (81, 82), i.e., a movement area for the movable body, and also position the actuator unit 20. This allows the actuator unit 20 to generate suitable vibrations without moving within the case 10.

[0253] The end spacers 22, 24 are non-magnetic resin spacers, and are molded from a resin such as polyethylene terephthalate (PBT).

[0254] <Movable body 60> The movable body 60 is supported inside the fixed cylindrical coil assembly 26 so as to be able to move back and forth along the inner surface 42a of the bobbin body 42 by elastic units 80 (81, 82) connected at the upper and lower ends.

[0255] In the vibration actuator 1D, the movable body 60 is supported within the case 10 between the bracket 14 and the bottom surface portion 124 so as to be capable of reciprocating movement in the opposing directions.

[0256] 25, 28, and 33, the movable body 60 includes magnets 50 (52, 54), yokes (a central yoke 62, upper and lower yokes 64, 66), sleeves 72, 74, a shaft 76, and spring stop members (fastening members) 77, 78.

[0257] The movable body 60 includes a rectangular magnetic body portion having a magnet 50 (52, 54) and a yoke (central yoke 62, upper and lower yokes 64, 66), and the movable body 60 as a whole has a rectangular outer shape when viewed from the axial direction, forming a prismatic movable body.

[0258] <Magnet 50 (Pair of Magnets 52, 54)> The magnet 50 includes a pair of magnets 52, 54 arranged with the same magnetic poles facing each other. The pair of magnets 52, 54 are magnetized in the axial direction, are arranged on either side of a central yoke 62, and are sandwiched between a pair of upper and lower yokes 64, 66 on the axial outer side.

[0259] The magnets 52, 54, central yoke 62, and upper and lower yokes 64, 66 each have a continuous through-hole formed therein, and a shaft 76 is inserted through these through-holes, with both ends 762, 764 of the shaft 76 fixed to the sleeves 72, 74.

[0260] The magnets 52, 54, the central yoke 62, and the upper and lower yokes 64, 66 are arranged in layers in the axial direction.

[0261] The magnets 52, 54, the central yoke 62, and the upper and lower yokes 64, 66 have the same outer shape and are each formed in the shape of a rectangular plate.

[0262] The magnets 52, 54, central yoke 62, and upper and lower yokes 64, 66 form a rectangular (rectangular) magnetic body portion in the movable body, and the outer surface of the magnetic body portion faces the inner surface 42a of the bobbin body 42 at a predetermined distance inside the inner surface 42a.

[0263] The magnets 52, 54 are of the same shape and are arranged so that the same magnetic poles face each other in the axial direction. A central yoke 62 is arranged between the magnets 52, 54. The thickness (axial length) of the magnets 52, 54 is greater than the thickness (axial length) of the central yoke 62, and for example, the height is approximately twice or more the thickness of the central yoke 62.

[0264] In the movable body 60, the center in the thickness direction of the central yoke 62 is the axial center of the movable body 60, and is disposed at a position facing the axial center of the central coil 32 in a direction perpendicular to the axial direction.

[0265] The magnets 52, 54 each have a thickness (axial length) that straddles the central coil 32 and the upper and lower coils 34, 36. The upper and lower yokes 64, 66 are disposed in positions that face the upper and lower coils 34, 36 perpendicular to the axial direction.

[0266] The magnets 52, 54 are arranged so that, when the movable body 60 is moved, at least a portion of them faces the central coil 32. The magnets 52, 54 are arranged so that the yoke 62 is sandwiched between surfaces 52 a, 54 a of the same magnetic pole (north poles or south poles).

[0267] The magnets 52 and 54 are made of, for example, sintered neodymium, and have through holes 522 and 542 formed in the center thereof, respectively.

[0268] <Central yoke 62, upper and lower yokes 64, 66> The central yoke 62 and upper and lower yokes 64, 66 are magnetic bodies formed from a magnetic metal such as SECC. The central yoke 62 and upper and lower yokes 64, 66, together with the magnets 50 (52, 54) and coils 30 (32, 34, 36), form a magnetic circuit. The case 10 may also be included in the magnetic circuit.

[0269] The central yoke 62 and the upper and lower yokes 64, 66 are arranged to cover the magnetic pole faces of the magnets 52, 54, respectively. As a result, the central yoke 62 and the upper and lower yokes 64, 66 concentrate the magnetic flux of the magnet 50 (52, 54) and allow it to flow efficiently without leakage, effectively distributing the magnetic flux flowing between the magnet 50 (52, 54) and the coil 30 (32, 34, 36).

[0270] Furthermore, the central yoke 62 and the upper and lower yokes 64, 66 function as part of the magnetic circuit, and also form a magnetic body together with the magnets 52, 54 in the movable body 60, and function as weights.

[0271] The central yoke 62 and the upper and lower yokes 64 and 66 are formed so that their outer circumferential surfaces are flush with the outer circumferential surfaces of the magnets 52 and 54 .

[0272] The central yoke 62 and the upper and lower yokes 64, 66 are arranged symmetrically above and below the magnets 52, 54, respectively, on the front and back surfaces of the central yoke 62. The central yoke 62 and the upper and lower yokes 64, 66 are attracted to the magnets 52, 54 and may be fixed to the magnets 52, 54 with, for example, a thermosetting adhesive such as epoxy resin or an anaerobic adhesive.

[0273] Through holes 622, 642, 662 that communicate in the axial direction with the through holes 522, 542 of the magnets 52, 54 are provided in the respective centers of the central yoke 62 and the upper and lower yokes 64, 66. A shaft 76 is inserted through the magnets 52, 54 and is positioned on the central axis of the movable body 60.

[0274] In the default non-vibrating state, the upper and lower yokes 64, 66 are positioned opposite the upper and lower coils 34, 36, respectively. They are formed as circular flat plates with the same surface shape as the magnets 52, 54, and their axial centers are located at the same height perpendicular to the axial direction. The upper and lower yokes 64, 66 prevent leakage flux in the magnetic circuit formed by the magnets 52, 54 and the coils 30 (32, 34, 36) sandwiching the central yoke 62, thereby creating an effective flow of magnetic flux.

[0275] <Sleeves 72, 74> The sleeves 72, 74 have the function of fixing the magnetic bodies (magnets 52, 54, central yoke 62, and upper and lower yokes 64, 66) to the elastic units 81, 82, and also function as weights for the movable body 60. The sleeves 72, 74 are arranged symmetrically in the axial direction so as to sandwich the magnets 50 (52, 54), central yoke 62, and upper and lower yokes 64, 66, and increase the vibration output of the movable body 60.

[0276] The sleeves 72, 74 are made of a non-magnetic material such as sintered copper metal, and are cylindrical bodies arranged radially outward from the through holes (through portions) 722, 742 along the central axis of the movable body 60. The sleeves 72, 74 are arranged between the pair of magnets 52, 54 and the elastic units 81, 82. In this embodiment, the sleeves 72, 74 are arranged between the pair of magnets 52, 54, the central yoke 62, and the upper and lower yokes 64, 66 and the elastic units 81, 82.

[0277] Since the sleeves 72 and 74 are made of a non-magnetic material, magnetic flux from the magnetic bodies (magnets 52 and 54, central yoke 62, upper and lower yokes 64 and 66) does not flow vertically, but can flow toward the coil 30 (32, 34, 36).

[0278] The sleeves 72, 74 are formed in a truncated cone shape with through holes 722, 742 respectively provided in the central portion along the axial direction. That is, the axially outer surfaces (outer surfaces) of the sleeves 72, 74 are inclined downward from the central portion toward the radially outward direction, and are formed so that the axial thickness becomes thinner from the central portion toward the radially outward direction.

[0279] In this way, because the sleeves 72, 74 are not cylindrical but truncated cones, when the movable body 60 moves in the axial direction, the movable area can be widened without contacting the elastic units 81, 82 (leaf spring 802). Note that by making the sleeves 72, 74 cylindrical, for example, the weight of the movable body 60 can be increased as desired.

[0280] The sleeves 72, 74 are fixed in an internally fitted state by inserting (for example, press-fitting) both end portions 762, 764 of the shaft 76 into one opening of the through-holes 722, 742, respectively.

[0281] The sleeves 72 and 74 are formed so as to contact the upper and lower yokes 64 and 66 over their entire surfaces.

[0282] The sleeves 72, 74 press the magnets 52, 54, central yoke 62, and upper and lower yokes 64, 66 from both ends of the shaft 76, stacking them axially and sandwiching them in close contact with each other.

[0283] Spring stop members 77 and 78 that connect the elastic units 81 and 82 are inserted into the sleeves 72 and 74 from the other openings of the through holes 722 and 742 , and the elastic units 81 and 82 are fastened via the spring stop members 77 and 78 .

[0284] The central end faces of the sleeves 72 and 74 where the other of the through holes 722 and 742 opens are in contact with and fixed to the elastic units 81 and 82 .

[0285] The shaft 76 is press-fitted and fixed between the magnets 52, 54 with their like poles butted together, and in a configuration in which both ends are sandwiched between the central yoke 62 and the upper and lower yokes 64, 66 (the magnetic body of the movable body 60). In this case, the vibration actuator 1D can be stably fixed to the magnetic body of the movable body 60 even in a configuration in which there is a strong repulsive force between the magnets 52, 54 with their like poles butted together.

[0286] Even if the movable body 60 has a pair of magnets 52, 54 arranged with the same magnetic poles facing each other, the shaft 76 that passes through them is fixed by press-fitting or the like to the sleeves 72, 74. As a result, both sleeves 72, 74 can be stably fixed by tightening the magnets 52, 54, which are sandwiched between the central yoke 62, via the upper and lower yokes 64, 66.

[0287] Furthermore, since the shaft 76 inserted into the movable body is pressed into and fixed to the sleeves 72 and 74, the movable body can be constructed by integrating the sleeves 72 and 74 with the magnetic material, and the movable body 60 and the elastic units 81 and 82 can be easily assembled.

[0288] In this embodiment, the sleeves 72 and 74 are formed to have the same shape, and the shaft 76 and the spring stop members 77 and 78 are fixed in the respective through holes 722 and 742 .

[0289] In the present embodiment, the sleeves 72, 74 are press-fitted onto a shaft 76 that passes through the pair of magnets 52, 54, the central yoke 62, and the upper and lower yokes 64, 66, thereby sandwiching and fixing the pair of magnets 52, 54, the central yoke 62, and the upper and lower yokes 64, 66. The sleeves 72, 74 may be fixed by adhesive bonding using, for example, a thermosetting adhesive such as epoxy resin or an anaerobic adhesive, in addition to press-fitting the shaft 76. The pair of magnets 52, 54, the central yoke 62, the upper and lower yokes 64, 66, and the shaft 76 may also be fixed by adhesive bonding using, for example, a thermosetting adhesive such as epoxy resin or an anaerobic adhesive.

[0290] Furthermore, because the sleeves 72 and 74 have the functions of fixing the movable body, serving as a weight, and fixing the spring, there is no need to assemble the components having each function separately. Simply providing the sleeves 72 and 74 in the movable body side magnetic circuit allows the elastic units 81 and 82, together with the weight, to be easily attached to the movable body 60, improving assembly efficiency.

[0291] <Elastic unit 80 (81, 82)> Fig. 34 is a vertical cross-sectional view of the elastic unit. Note that the elastic units 81 and 82 have the same basic configuration, so they will be denoted by corresponding reference numerals and will be described in parallel.

[0292] As shown in FIGS. 25, 27, and 28, the elastic unit 80 (81, 82) supports the movable body 60 so that it can move back and forth in the vibration direction relative to a fixed body including the case 10 and the bobbin 40, etc.

[0293] The elastic units 81, 82 sandwich the movable body 60 in the vibration direction (axial direction) of the movable body 60, and are installed so as to intersect with the vibration direction on both the upper and lower ends of the movable body 60 and on both opening edge portions 452, 462, which are the upper and lower ends spaced apart in the axial direction of the bobbin 40. Each of the elastic units 81, 82 is formed in a plate shape and is formed so as to be freely displaceable between its outer periphery and inner periphery.

[0294] 25, 27, and 28, the elastic units 81 and 82 are connected to the upper and lower ends of the movable body 60 at their inner peripheral portions 814, and are connected to the fixed body (bobbin 40) at their outer peripheral portions 815. In this embodiment, the elastic units 81 and 82 are spaced apart from each other in the vibration direction and are arranged opposite each other in a direction perpendicular to the vibration direction.

[0295] As shown in Figures 25, 27, 28 and 34, the elastic units 81 and 82 each have a pair of leaf springs 802 and 804, a frame-shaped spring holder 806 interposed between the pair of leaf springs 802 and 804, and spring stop members 77 and 78.

[0296] The elastic units 81, 82 are elastic units 80 that are similarly formed and have the same configuration, except for the different orientations of the spring stop members 77, 78 inserted into the through holes 812 and the positions of the annular collar portions 808, 810 that secure them. Therefore, in the following, the upper elastic unit 81 will be referred to as the elastic unit 80, and the upper elastic unit 81 will be described with reference to Figure 28, and the lower elastic unit 82 will be described with reference to Figure 34.

[0297] The elastic unit 81 is joined by inserting the spring stop members 77 and 78 into the through-holes 812 in a state where a spring holder 806 is sandwiched between a pair of leaf springs 802 and 804 .

[0298] The leaf springs 802, 804 are preferably elastically deformable (freely deformable) and made of a non-magnetic material. The leaf springs 802, 804 are formed, for example, by processing a non-magnetic metal plate such as SUS into a thin, flat, disc-shaped spiral spring. Because the elastic unit 81 is formed in a flat plate shape, it is possible to improve positional accuracy, i.e., improve processing accuracy, compared to a conical spring.

[0299] 28 and 34, the leaf springs 802, 804 have a central annular inner peripheral portion 814 that forms the inner spring end, a frame-shaped outer peripheral portion 815 that forms the outer spring end, and a deformed arm portion 816 that is arc-shaped in plan view and is interposed between the inner peripheral portion 814 and the outer peripheral portion 815. Note that leaf springs of similar shapes may be used for the leaf springs 802, 804. If the elastic unit 80 is constructed using two leaf springs 802, 804 that have the same configuration, the number of parts can be reduced, thereby reducing product costs.

[0300] The outer circumferential portion 815 is disposed radially outward of the inner circumferential portion 814 (outward of the inner circumferential portion 814 in a direction perpendicular to the axial direction).

[0301] The leaf springs 802, 804 are fixed at the outer periphery 815 inside the case 10 by a resin spring holder 806, a resin bobbin 40, and end spacers 22, 24, and the movable body 60 is positioned so as not to come into contact with the inner surface of the bobbin 40.

[0302] The leaf springs 802 and 804 have two deformed arm portions 816, and as shown in FIG. 28, the leaf springs 802 and 804 are arranged so that the spiral directions thereof are opposite to each other with the spring holder 806 interposed therebetween.

[0303] As a result, when the leaf springs 802 and 804 deform together in the axial direction, they deform in different torsional directions, which is different from the translational direction (here, the direction of circumferential movement on a plane perpendicular to the vibration direction) that they would move in if they were arranged in the same spiral orientation. The circumferential movements of the deforming leaf springs 802 and 804 (mainly the deforming arm portion 816) cancel each other out, and each elastic unit 81 (80) does not move in a twisting direction (circumferential direction) when moving in the axial direction.

[0304] Notches 817 are formed in the leaf springs 802 and 804, and engage with the protrusions 807 and 809 of the spring holder 806. The protrusions 807 and 809 are engaged with the notches 817, and the spring holder 806 is positioned between the outer peripheries 815 of the leaf springs 802 and 804, and the leaf springs 802 and 804 are positioned to sandwich the spring holder 806 while ensuring their deformation range.

[0305] The spring holder 806 is formed in a frame shape surrounding the deformation regions of the leaf springs 802, 804, and abuts on its front and back surfaces against the outer periphery 815 of the leaf springs 802, 804. The spring holder 806 also functions as a spacer that provides a space between the pair of leaf springs 802, 804 to allow deformation, and can hold the pair of leaf springs 802, 804 in a spaced-apart state. The spring holder 806 is preferably fixed to the outer periphery 815 of the leaf springs 802, 804 on its front and back surfaces. Protrusions 807, 809 are provided on the front and back surfaces of the spring holder 806 (surfaces separated by the outer periphery 815).

[0306] The protrusions 807 and 809 are appropriately engaged with the notch 817 and the notches 4522 and 4622 of the opening edges 452 and 462 to position them relative to each other.

[0307] The leaf springs 802, 804 are fixed by an annular collar portion 808 arranged between the leaf springs 802, 804 inside the spring holder 806, a collar portion 810 arranged adjacent to the outside of the leaf spring 804, and a spring stop member 77 (78) that passes through these collar portions 808, 810.

[0308] The spring stop members 77, 78 are inserted into the through holes 812 of the elastic units 81, 82 to fix the elastic units 81, 82 to the movable body 60 (specifically, the sleeves 72, 74). Rivets or the like may be used as the spring stop members 77, 78.

[0309] In this embodiment, the spring stop members 77, 78 are formed in the same shape, and have axial insertion portions 772, 782 and flanges 774, 784 provided on the edges of one ends of the insertion portions 772, 782. The spring stop members 77, 78 are made of a non-magnetic material, such as copper.

[0310] The insertion portions 772, 782 are inserted through the through-holes 812 and collar portions 808, 810 of the elastic units 81, 82, respectively, and are fixed in an inserted state in the through-holes 722, 742 of the sleeves 72, 74. The insertion portions 772, 782 are fixed by press-fitting into the through-holes 722, 742. The insertion portions 772, 782 may be fitted into the collar portions 808, 810, whereby the leaf springs sandwiched between the collar portions 808, 810 are fixed to the insertion portions 772, 782.

[0311] The collar portions 808 and 810 are made of a non-magnetic material, such as copper. The collar portion 808 is disposed between the leaf springs 802 and 804 and maintains the spacing between inner circumferential portions 814 of the leaf springs 802 and 804. The spring stop members 77 and 78 are press-fitted into the collar portion 810, and the collar portion 810 is integrated with the leaf springs 802 and 804.

[0312] The flanges 774, 784 fix the inner peripheral portions of the elastic units 81, 82 (corresponding to the inner peripheral portion 814 of the leaf spring) in a sandwiched state together with the sleeves 72, 74. The insertion portions 772, 782 and the through holes 722, 742 may be joined by welding, adhesive, crimping, or the like, or by a combination of welding, adhesive, and crimping.

[0313] In this embodiment, each of the multiple elastic units 81, 82 uses multiple spiral-shaped leaf springs, which are attached to both ends of the movable body 60 that are spaced apart in the vibration direction, thereby elastically supporting the movable body 60 relative to the fixed body (bobbin 40).

[0314] In the elastic units 81, 82 of this embodiment, the spiral directions of the plurality of leaf springs 802, 804 are arranged in different directions for each elastic unit 81, 82 and fixed to the movable body 60. This allows the elastic units 81, 82 to move the movable body 60 straight in the axial direction (vibration direction), and enables the generation of an appropriately increased vibration output.

[0315] If the spiral directions of the leaf springs 802, 804 supporting the movable body from above and below are all in the same direction, when the amount of movement of the movable body 60 increases, the movable body moves in the translational direction while rotating slightly.

[0316] In contrast to this, in each of the elastic units 81 and 82 of the present embodiment, the leaf springs 802 and 804 are arranged so that the spiral directions of the plurality of leaf springs 802 and 804 are opposite to each other. As a result, the rotational movements of the leaf springs 802 and 804 cancel each other out, and when the inner peripheral portion moves in the axial direction, it is less likely to rotate and moves straight in the axial direction.

[0317] It is also possible to provide a damping material that damps vibrations generated in the leaf springs 802 and 804. The damping material damps sharp spring resonance in the leaf springs 802 and 804, and prevents, for example, large differences in vibration due to frequency caused by significant increase in vibration near the resonance frequency of the entire elastic unit 81 (80).

[0318] This allows the movable body 60 to suppress the resonance peak before plastic deformation, and to generate stable vibrations over a wide range between the bottom surface 124 of the case 10 and the bracket 14 without contacting either of them, preventing abnormal noise from being generated by contact.

[0319] In the elastic unit 81 (80), two leaf springs 802, 804 are deformed at the upper and lower ends of the movable body 60, thereby supporting the movable body 60 so that it can move axially.

[0320] When the elastic units 81 (80) are attached to the opening edge portions 452, 462 of the coil assembly 26, the outer peripheries 815 of the leaf springs 802, 804 are clamped in the axial direction by the opening edge portions 452, 462, the spring holder 806, and the end spacers 22, 24.

[0321] Meanwhile, the inner circumferential portions of the elastic unit 81 (80) (portions corresponding to the inner circumferential portions 814 of the leaf springs 802, 804) are fixed to the upper and lower ends of the movable body 60 (ends of the sleeves 72, 74) via the spring stop members 77, 78. As a result, the elastic unit 81 (80) is bridged between the opening edge portions 452, 462 and the upper and lower ends of the movable body 60 (ends of the sleeves 72, 74) so ​​as to be perpendicular to the axial direction.

[0322] The deforming arm portion 816 and inner circumferential portion 814 of the elastic unit 81 are arranged within a movable area that is freely movable in the axial direction, and the deforming arm portion 816 and inner circumferential portion 814 of the elastic unit 82 are arranged within a movable area that is freely movable in the axial direction.

[0323] The elastic unit 81 (80) is clamped within the case 10 between the end faces of the upper and lower opening edge portions 452, 462 of the coil assembly 26 (bobbin 40) and the end spacers 22, 24, and is arranged along a direction perpendicular to the vibration direction.

[0324] In the vibration actuator 1D, the actuator unit 20 is covered by a magnetic case 10. This allows for a configuration in which only the central portion of the movable body 60 (magnets 52, 54, central yoke 62, upper and lower yokes 64, 66) is magnetic, making it possible to reduce leakage magnetic flux and the number of parts without using a separate magnetic shielding material to surround the magnetic parts, thereby maximizing the number of internal parts.

[0325] The elastic units 81 and 82 each use a pair of leaf springs 802 and 804, with each leaf spring having two deforming arms 816. This means that, unlike a configuration in which the leaf spring requires three or more deforming arms 816, the deforming arms 816 of the leaf springs 802 and 804 can be lengthened to vibrate at a low resonance frequency even when the size is reduced.

[0326] The vibration actuator 1D has a structure in which two spiral-type leaf springs 802, 804 are arranged on one side (one axial side) of the movable body 60, making it possible to realize an actuator that is small in size but has leaf springs 802, 804 that are compatible with low resonance frequencies.

[0327] The elastic units 81 and 82 can be configured by combining two identical leaf springs 802 and 804 with the front and back reversed. This cancels out the torsional movement of the movable body 60 and the rotational movement of the springs when they expand and contract, thereby suppressing higher-order resonance.

[0328] The positions and spacing of the two spiral leaf springs 802, 804 are set by the spring stop members 77, 78, collar portions 808, 810, and spring holder 806. This allows them to be used as an integrated elastic unit, making assembly with the movable body 60 easy.

[0329] Since the magnets 52 and 54 are arranged with the same poles butted together, a thrust can be generated with a larger magnetic force even in a small size.

[0330] A magnetic circuit (three slots) is configured with three coils (center coil 32, upper coil 34, and lower coil 36) for the pair of magnets 52, 54. This reduces leakage of the generated magnetic force, enabling effective generation of magnetic force.

[0331] In the vibration actuator 1D, the leaf springs 802, 804 in the elastic units 81, 82 may be provided in the same winding direction for each of the elastic units 81, 82.

[0332] That is, in vibration actuator 1D, each of the pair of leaf springs 802, 804 is a spiral spring having a deformation arm portion 816 suspended between an inner peripheral portion 814 and an outer peripheral portion 815, and each pair of elastic bodies is arranged with the same winding direction. In addition, each of the pair of elastic units 81, 82 is arranged with a different winding direction.

[0333] With this configuration, the elastic units 81 and 82 that sandwich the movable body 60 from above and below cancel out the torsional movement of the movable body 60 when it is driven and the rotational movement when the spring expands and contracts, thereby suppressing higher-order resonance.

[0334] <Operation of Vibration Actuator 1D> In vibration actuator 1D, surfaces 52a and 54a of magnet 50 (52, 54) that face each other in the magnetization direction have the same magnetic polarity (north poles or south poles). In addition, surfaces 52a and 54a of the pair of magnets 52 and 54 with the same magnetic polarity sandwich a central yoke 62, and upper and lower yokes 64 and 66 are respectively positioned in contact with the back surfaces of the pair of magnets 52 and 54, thereby constituting the magnetic body of movable body 60.

[0335] In vibration actuator 1D, movable body 60 is considered to correspond to the mass portion in a vibration model of a spring-mass system, and therefore, when the resonance is sharp (has a steep peak), the steep peak is suppressed by damping the vibration.

[0336] Fig. 35 is a diagram schematically showing the magnetic circuit of a vibration actuator according to embodiment 3. In vibration actuator 1D, the magnetic circuit shown in Fig. 35 is formed. In Fig. 35, surfaces 52a, 54a of a pair of magnets 52, 54 are designated as north pole faces. Furthermore, in vibration actuator 1D, the coil axis of coil 30 (32, 34, 36) is arranged so as to be perpendicular to the flow of magnetic flux that flows from central yoke 62, which sandwiches magnets 52, 54 in the vibration direction, to central coil 32.

[0337] Specifically, the magnetic flux is emitted from the surface side of the pair of magnets 52, 54, passes through the central yoke 62, and is radiated in a radial direction perpendicular to the axial direction toward the central coil 32. The magnetic flux radiated from the outer periphery of the central yoke 62 to the central coil 32 passes through the peripheral wall portion 122 of the case 10, which is made of a magnetic material, and enters the upper and lower yokes 64, 66 via the upper and lower coils 34, 36. The magnetic flux is then incident on the magnets 52, 54 from the upper and lower yokes 64, 66.

[0338] In this manner, in the vibration actuator 1D, a magnetic flux flow mf is formed in the order of the pair of magnets 52, 54, central yoke 62, central coil 32, peripheral wall portion 122, upper and lower coils 34, 36, upper and lower yokes 64, 66, and magnets 52, 54.

[0339] 35, when current is applied, the magnetic field of the magnets 52 and 54 interacts with the current flowing through the coil 30 (32, 34, 36), generating a Lorentz force in the -f direction in the coil 30 (32, 34, 36) according to Fleming's left-hand rule. Because the coil 30 (32, 34, 36) is fixed to the fixed body (bobbin 40), a force opposite to this Lorentz force in the -f direction is generated in the movable body 60 having the magnets 52 and 54 as a thrust in the F direction, according to the law of action and reaction. As a result, the movable body 60 having the magnets 52 and 54 moves in the F direction, that is, toward the bracket 14.

[0340] Furthermore, when the direction of current flow in the coils 30 (32, 34, 36) is reversed and current is passed through the coils 30 (32, 34, 36), a Lorentz force is generated in the opposite direction, f-direction. Due to the generation of this Lorentz force in the f-direction, in accordance with the law of action and reaction, a force opposite to the Lorentz force in the f-direction is generated as a thrust (thrust in the -F direction) on the movable body 60, and the movable body 60 moves in the -F direction, i.e., toward the bottom surface 124 of the fixed body (bobbin 40).

[0341] In the vibration actuator 1D, when no current is applied (when not driven, when not vibrating), the movable body 60 returns to its original position due to the function of the magnetic spring caused by the magnetic attraction force generated between the magnets 52, 54 and the peripheral wall portion 122 of the case 10, and the restoring force of the elastic units 81, 82.

[0342] In the vibration actuator 1D, the magnetic circuit including the magnets 52, 54, the central coil 32, and the upper and lower coils 34, 36 is surrounded by the case 10 whose peripheral wall 122 functions as an electromagnetic shield (magnetic shield).

[0343] In this way, the vibration actuator 1D has shock resistance and can output a suitable bodily vibration with high vibration expression.

[0344] The vibration actuator 1D is driven by an AC wave input to the coils 30 (32, 34, 36) from a power supply unit (for example, the drive control unit 203 shown in FIGS. 70 and 71). In other words, the direction of current flow through the coils 32, 34, 36 switches periodically, and a thrust in the F direction on the bracket 14 side and a thrust in the −F direction on the bottom surface portion 124 side act alternately on the movable body 60. This causes the movable body 60 to vibrate.

[0345] Here, the driving principle of the vibration actuator 1D will be briefly explained. In the vibration actuator 1D of this embodiment, the mass of the movable body 60 is m [kg], the spring constant of the springs (leaf springs 802, 804) is K ｓｐ In this case, the movable body 60 has a resonance frequency F ｒ It vibrates at [Hz].

[0346]

[0347] Since the movable body 60 is considered to constitute a mass part in a vibration model of a spring-mass system, the resonance frequency F of the movable body 60 is applied to the coil 30 (32, 34, 36). ｒ When an AC wave having a frequency equal to the resonant frequency F of the movable body 60 is input, the movable body 60 enters a resonant state. ｒ By inputting an AC wave having a frequency substantially equal to the frequency of the movable body 60, the movable body 60 can be vibrated efficiently.

[0348] The equation of motion and circuit equations showing the driving principle of the vibration actuator 1D are shown below: The vibration actuator 1D is driven based on the equation of motion shown in the following equation (2) and the circuit equation shown in the following equation (3).

[0349]

[0350]

[0351] That is, the mass m [kg], displacement x(t) [m], thrust constant K f [N / A], current i(t) [A], spring constant K sp [N / m], damping coefficient D [N / (m / s)], etc. can be changed as appropriate within the range that satisfies formula (2). ｅ [V / (rad / s)] can be changed as appropriate within a range that satisfies formula (3).

[0352] In this way, in the vibration actuator 1D, the mass m of the movable body 60 and the spring constant K of the elastic units 81 and 82 (leaf springs) ｓｐ The resonant frequency F is determined by ｒ In this case, a large vibration output can be efficiently obtained.

[0353] Furthermore, vibration actuator 1D satisfies equations (2) and (3) and is driven by a resonance phenomenon using the resonance frequency shown in equation (1). As a result, with vibration actuator 1D, if a damping material is present, the only power consumed in the steady state is the loss due to the damping material, and it can be driven with low power consumption, that is, the movable body 60 can be made to move back and forth linearly (vibrate) with low power consumption. Furthermore, by increasing the damping coefficient D, it is possible to generate vibrations over a wide frequency range.

[0354] The vibration actuator 1D has a rectangular parallelepiped shape, and the movable body 60 also has a rectangular parallelepiped shape. This structure has a larger volume than a cylindrical actuator of the same diameter, and therefore when placed in a similar space, the space can be fully utilized to form a more effective magnetic circuit.

[0355] Fourth Embodiment FIG. 36 is a vertical cross-sectional view showing the configuration of the main part of a vibration actuator according to a fourth embodiment, and FIG. 37 is an external perspective view of an actuator unit of the vibration actuator shown in FIG.

[0356] The vibration actuator 1E according to embodiment 4 is formed by partially modifying or adding to the configuration of the vibration actuator 1D according to embodiment 3. In the following description of the vibration actuator 1E, components that are the same as those of the vibration actuator 1D are given the same names and reference numerals, and descriptions thereof will be omitted.

[0357] As shown in the vibration actuator 1E according to embodiment 4 shown in Figures 36 and 37, in the configuration of the vibration actuator 1D according to embodiment 3, an electromagnetic shield portion (magnetic shield portion) 90 may be provided between the coils 32, 34, 36 and the case main body 12 (circumferential wall portion 122).

[0358] The vibration actuator 1E has the same configuration as the vibration actuator 1D, except for the configuration of the coil assembly 26E.

[0359] In the actuator unit 20E, an electromagnetic shield portion 90 is provided on the outer peripheral surface of the coil assembly 26.

[0360] The electromagnetic shielding portion 90 is a cylindrical magnetic body that is disposed in a position that covers the coils 32, 34, 36 from the radially outer side.

[0361] The electromagnetic shield portion 90 covers the central coil 32, the upper coil 34, and the lower coil 36 housed in the recesses 40a, 40b, and 40c that open to the outside of the bobbin 40E from the outside in the circumferential direction.

[0362] In the bobbin 40E, the radially outer length of the intermediate flanges 43, 44 that sandwich the central coil 32 is shorter than that of the upper and lower flanges 45, 46, and the electromagnetic shielding portion 90 is disposed between the upper and lower flanges 45, 46. As a result, the electromagnetic shielding portion 90 disposed on the outer periphery of the intermediate flanges 43, 44 is disposed flush with the outer surfaces of the upper and lower flanges 45, 46.

[0363] The electromagnetic shielding portion 90 is positioned so that the center of its length in the vibration direction is at the same height as the combined center of the vibration direction of the magnets 52, 54 positioned inside. The shielding effect of this electromagnetic shielding portion 90 can reduce magnetic flux leakage to the outside of the vibration actuator.

[0364] The electromagnetic shield portion 90 prevents leakage of magnetic flux to the outside of the vibration actuator 1E in the magnetic circuit including the central coil 32, upper coil 34, lower coil 36, magnets 52, 54, and central yoke 62, upper yoke 64, and lower yoke 66, thereby creating a stronger magnetic relationship.

[0365] Furthermore, the electromagnetic shield 90 can increase the thrust constant in the magnetic circuit, thereby improving electromagnetic conversion efficiency. The electromagnetic shield 90 functions as a magnetic spring together with the magnets 52, 54 by utilizing the magnetic attraction of the magnets 52, 54. This can reduce the stress on the elastic units 81, 82 when they are used as mechanical springs, thereby improving the durability of the elastic units 81, 82.

[0366] By changing the dimensions (shape and size) of the electromagnetic shield portion 90, the magnitude of the thrust of the movable body 60 due to the magnetic attraction force may be changed, as shown in Figures 38 and 39, for example. Note that, for all of the magnetic shields 90 described below, it is preferable that they are formed symmetrically around the entire circumference of the movable body 60, centering on the axis of the movable body 60, so as to surround the magnetic circuit portion (including magnets 52, 54) of the movable body 60. It is preferable that the electromagnetic shield portion has a shape that is arranged symmetrically in the radial direction, with a predetermined interval between them. The electromagnetic shield portion can form a suitable flow of magnetic flux in the circumferential direction.

[0367] FIG. 38 is a vertical cross-sectional view showing the configuration of the main parts of a first modified example of a vibration actuator according to the fourth embodiment, and FIG. 39 is a perspective view showing the appearance of an actuator unit of the vibration actuator shown in FIG.

[0368] 38 and 39 , the vertical length (vibration direction) of the electromagnetic shield portion (magnetic shield portion) 91 provided on the outer periphery of the bobbin 40E may be shorter than the vertical length of the electromagnetic shield portion 90. For example, the vertical length (vibration direction) of the electromagnetic shield portion (magnetic shield portion) 91 may be shorter than the vertical length of the coil 30. Furthermore, the vertical length of the electromagnetic shield portion 91 may be shorter than the vertical length between the front surface of the upper yoke 64 and the back surface of the lower yoke 66.

[0369] That is, the electromagnetic shield part 91 is disposed so that its axial center faces the axial center of the combined configuration of the coils 32, 34, and 36, and its axial length is shorter than the axial lengths of the coils 32, 34, and 36. The electromagnetic shield part 91 covers the central coil 32 and the intermediate flanges 43 and 44 on the outer periphery of the bobbin 40E, and only covers about half of the upper and lower coils 34 and 36.

[0370] In this way, the flow of magnetic flux in the magnetic circuit can be appropriately adjusted by adjusting the length of the electromagnetic shielding portion 91. By fixing the electromagnetic shielding portion 91 in advance inside the case body 12, it can be positioned midway between the upper and lower flanges 45, 46 on the outer circumferential surface of the bobbin 40E of the actuator unit 20F.

[0371] FIG. 40 is a perspective view showing the appearance of an actuator unit in a second modification of the vibration actuator according to the fourth embodiment.

[0372] 40 , an opening 93 may be provided in a part of the electromagnetic shield portion (magnetic shield portion) 92. Like actuator unit 20F, actuator unit 20G differs from actuator unit 20E only in the configuration of the electromagnetic shield portion.

[0373] In the actuator unit 20G, the electromagnetic shielding portion 92 is rectangular and cylindrical, and has radially penetrating openings 93 at each of the corners symmetrically positioned about the central axis. This allows the flow of magnetic flux in the magnetic circuit to be appropriately adjusted, as in variant example 1.

[0374] In this way, in a miniaturized vibration actuator, the spring constant for vibration in the low frequency band or the high frequency band can be adjusted by adjusting the size of the electromagnetic shielding portion in addition to setting the mechanical spring dimensions, thereby increasing the freedom in vibration setting.

[0375] Fifth Embodiment FIG. 41 is a longitudinal sectional view showing the main configuration of a vibration actuator according to a fifth embodiment, and FIG. 42 is a perspective half sectional view showing the main configuration of the vibration actuator shown in FIG.

[0376] The vibration actuator 1H according to embodiment 5 is formed by partially modifying or adding to the configuration of the vibration actuator 1D according to embodiment 3. In the following description of the vibration actuator 1H, components that are the same as those in the vibration actuator 1D are given the same names and reference numerals, and descriptions thereof will be omitted.

[0377] As in the vibration actuator 1H shown in Figures 41 and 42, in a bobbin body 42H having the same basic configuration as the bobbin body 42 of the vibration actuator 1D of embodiment 3, openings 49 may be formed in opposing positions in a direction perpendicular to the axial direction.

[0378] The vibration actuator 1H has the same configuration as the vibration actuator 1D of the third embodiment, except for the configuration of the coil assembly 26H. The other configurations are the same.

[0379] 42, in the coil assembly 26H of the vibration actuator 1H, the opening 49 in the bobbin body 42H of the bobbin 40H is formed in the bottom surface portion of the recess 40a sandwiched between the intermediate flanges 43, 44. Since the central coil 32H is disposed in this recess 40a, the opening 49 is closed by the central coil 32H.

[0380] The central coil 32H has a smaller inner diameter than the upper and lower coils 32, 34. The central coil 32H is provided so as to face the interior through the opening 49, and is arranged so that its inner peripheral surface 42a is flush with the inner peripheral surface of the bobbin body 42H that separates the upper and lower parts of the opening 49.

[0381] This allows the central coil 32H to be arranged so as to sandwich the outer circumferential surface 60a of the movable body 60, with the portions within the opening 49 (here, a pair of opposing portions) facing and close to the outer surface of the movable body 60. This further increases the magnetic attraction force. Note that ribs (rib pieces) 422 that extend in the axial direction (up and down direction) and have the same function as the rib 420 are provided on the inner circumferential surface 42a at the top and bottom of the opening 49.

[0382] Sixth Embodiment FIG. 43 is a cross-sectional perspective view showing the configuration of the main part of a vibration actuator according to a sixth embodiment, and FIG. 44 is an exploded perspective view of the movable body of the vibration actuator shown in FIG.

[0383] Vibration actuator 1J of embodiment 6 differs from vibration actuator 1D of embodiment 3 in the configuration of movable body 600, but the other components are similar and have similar functions. Therefore, only the different components will be described below, and similar components will be given the same names and symbols and will not be described again.

[0384] 43 and 44 has a hollow case 10, and an actuator unit 20J housed in the hollow case 10 together with end spacers 22, 24. The actuator unit 20J has a coil assembly 26 as a fixed body having a coil 30 (32, 34, 36), a movable body 600 housed within the coil assembly 26, and elastic units 81, 82 that support the movable body 600 so that it can move freely.

[0385] The movable body 600 includes a magnet 50 (52, 54), a central yoke 62, upper and lower yokes 640, 660, sleeves 720, 740, a shaft 76, and spring stop members 77, 78.

[0386] In the movable body 600, similarly to the movable body 60, a pair of magnets 52, 54 sandwich a central yoke 62 with the same magnetic pole faces (surfaces 52 a, 54 a) facing each other, and upper and lower yokes 640, 660 are arranged adjacent to the axially outer sides of the pair of magnets 52, 54, respectively. A shaft 76 is inserted through the pair of magnets 52, 54, the central yoke 62, and the upper and lower yokes 640, 660.

[0387] The upper and lower yokes 640, 660 are formed with openings 6420, 6620 that are larger than the outer diameter of the shaft 76 and penetrate the yokes in the axial direction. One end of the sleeves 720, 740 is inserted and fitted into the openings 6420, 6620.

[0388] One end of the sleeve 720, 740 faces the magnet 52, 54 and is fixed in contact with the magnet 52, 54 together with the upper and lower yokes 640, 660. Note that the one end of the sleeve 720, 740 does not have to be in contact with the magnet 52, 54 as long as it is configured to be fixed within the openings 6420, 6620. The spring stop members 77, 78 of the elastic units 81, 82 are inserted into the through holes (through portions) 702, 704 of the sleeve 720, 740, together with the shaft 76. The sleeve 720, 740 may be fixed by being press-fitted into the upper and lower yokes 640, 660.

[0389] As a result, in vibration actuator 1J, the movable body 600 can connect the sleeves 720, 740 to the elastic units 81, 82 on the axially outer side of the upper and lower yokes 640, 660 without coming into full contact with them. That is, as shown in Figure 43, the upper surface 640a of the upper yoke 640 is configured to face the leaf spring 804, and no sleeve is disposed on the upper surface 640a. This makes it possible to reduce the weight of the sleeve disposed on the upper surface 640a, and also reduces the weight of the ends in the axial direction.

[0390] Seventh Embodiment Fig. 45 is a longitudinal sectional view showing the configuration of the main parts of a vibration actuator according to a seventh embodiment, and Fig. 46 is an external perspective view of the actuator unit of the vibration actuator shown in Fig. 45. Also, Fig. 47 is an external perspective view showing the movable body and elastic support part within the actuator unit.

[0391] The vibration actuator 1K according to the seventh embodiment is formed by partially modifying or adding to the configuration of the vibration actuator 1J according to the sixth embodiment. In the following description of the vibration actuator 1K, components that are the same as those of the vibration actuator 1J are given the same names and reference numerals, and their description will be omitted.

[0392] As in the vibration actuator 1K according to embodiment 7 shown in Figures 45 and 46, in the configuration of the vibration actuator 1J, the elastic units 81 and 82 may be replaced with a conical coil spring 850, which is an elastic body in the shape of a coil spring.

[0393] The conical coil spring 850 is a conical coil spring, and its upper base portion with a small diameter is fitted onto the sleeves 720 and 740 protruding from the upper and lower ends of the movable body 600 .

[0394] 46, with conical coil springs 850, 850 arranged above and below, actuator unit 20K is housed in case 10 (see FIG. 45). At this time, the lower base portion of conical coil spring 850, which has a larger diameter, presses against bottom surface 124 of case main body 12 and bracket 14, supporting movable body 600.

[0395] In the vibration actuator 1K, an electromagnetic shield section (magnetic shield section) 90 (see FIG. 14, etc.) may be provided between the coils 32, 34, 36 and the case main body 12 (peripheral wall section 122).

[0396] <Embodiment 8> Fig. 48 is an external perspective view of an actuator unit of a vibration actuator according to this embodiment 8, and Fig. 49 is an external perspective view of a leaf spring of the actuator unit shown in Fig. 48. Also, Fig. 50 is an exploded perspective view showing a movable body of the actuator unit of Fig. 48.

[0397] The actuator unit 20L of the vibration actuator according to embodiment 8 is formed by partially modifying or adding to the configuration of the actuator unit in vibration actuator 1K according to embodiment 6. In the following, when describing the actuator unit provided in the vibration actuator of embodiment 8, components that are the same as those in vibration actuator 1K will be given the same names and symbols and will not be described again.

[0398] As shown in an actuator unit 20L of a vibration actuator according to the eighth embodiment shown in FIG. 48, the leaf springs 802 and 804 of the elastic units 81 and 82 are replaced with frameless leaf springs 802L and 804L.

[0399] The elastic unit 80L has leaf springs 802L and 804L, a spring holder 806, and spring stop members 77 and 78.

[0400] 49 , leaf springs 802L, 804L have a configuration in which there is no outer peripheral portion connected in a frame shape, unlike leaf springs 802, 804. Leaf springs 802L, 804L have an inner peripheral portion 814, deforming arm portions 816 formed in a spiral shape, and outer peripheral end portions 818 of deforming arm portions 816, and are arranged so as to sandwich spring holder 806 therebetween.

[0401] As shown in FIG. 50, inside the bobbin 40, the elastic unit 80L is fixed to the upper and lower ends of the movable body 600 via spring stop members 77, 78.

[0402] The outer peripheral portions of the leaf springs 802L, 804L are fixed to the bobbin 40 by having the ends 818 sandwiched in the vertical direction between the spring holder 806, the opening edge 452, and the end spacers 22, 24 (see FIG. 45). Using such springs can reduce costs.

[0403] <Ninth Embodiment> Fig. 51 is an external perspective view of an actuator unit of a vibration actuator according to the ninth embodiment, and Fig. 52 is an exploded perspective view of the actuator unit shown in Fig. 51. Also, Fig. 53 is an exploded perspective view of an elastic unit of the actuator unit shown in Fig. 52, and Fig. 54 is a longitudinal sectional view showing the configuration of the main parts of a vibration actuator having the actuator unit shown in Fig. 52.

[0404] The vibration actuator 1M according to the ninth embodiment is formed by partially modifying or adding to the configuration of the actuator unit 20L of the vibration actuator according to the eighth embodiment. In the following description of the vibration actuator 1 according to the ninth embodiment, components that are the same as those of the vibration actuator 1J are given the same names and symbols, and description thereof will be omitted.

[0405] As shown in the actuator unit 20M of the vibration actuator 1M according to embodiment 9 shown in Figures 51 to 54, the vibration actuator has an elastic unit 80M configured without using a spring holder, instead of the elastic unit 80L.

[0406] As shown in FIG. 52, the actuator unit 20M accommodates a movable body 600 within the coil assembly 26, and the movable body 600 is elastically supported by being connected to the coil assembly 26 above and below in the vibration direction by elastic units 80M.

[0407] As shown in FIG. 53, the elastic unit 80M has a collar portion 808 interposed between leaf springs 802L and 804L, a spring stop 78 inserted into the central opening between them, and a collar portion 810 fitted onto the tip end side.

[0408] The elastic units 80M are arranged in the upper and lower openings of the coil assembly 26, and are arranged in the case 10 so that the ends 818 of the leaf springs 802L and 804L do not overlap in the vertical direction.

[0409] Therefore, as shown in FIG. 54, these ends 818 are positioned parallel to each other and are sandwiched between the opening edge of the bobbin 40 and the end spacers 22M and 24M from above and below.

[0410] End spacer 24M (similar to end spacer 22M) is provided with stepped portions 247, 248 that sandwich end portions 818 of leaf springs 802L, 804L, which have different heights above and below. Corresponding stepped portions are also formed on the bobbins, and by sandwiching leaf springs 802L, 804L between these stepped portions, end spacers 22M, 24M securely hold leaf springs 802L, 804L.

[0411] Although the vibration actuators 1D, 1E, 1H, 1J, 1K, etc. of the above-described embodiments are provided with the ribs 420, 422, the ribs 420, 422 may be omitted.

[0412] Incidentally, in actuators that are driven by resonance, such as those described in Patent Document 1, it is known that the vibration acceleration peaks at the resonance frequency of the movable body (including the yoke), and that this peak is steep. For this reason, when attempting to obtain strong vibrations over a wide frequency range with conventional vibration actuators, there is a demand for suitable adjustment of the vibration without reducing the output. Another variation of a vibration actuator that achieves this is described below.

[0413] (Another Modification 1) Fig. 55 is a perspective cross-sectional view showing the configuration of the main parts of a vibration actuator as another modification 1 of the vibration actuator 1 according to embodiment 1, and Fig. 56 is a perspective view of the coil assembly from which the cylindrical conductor has been removed in the vibration actuator of Fig. 55. Also, Fig. 57 is a perspective cross-sectional view of the coil assembly from which the movable body has been removed in the vibration actuator of Fig. 55.

[0414] 55 and 56 is configured such that the actuator unit 20N of the vibration actuator 1N according to embodiment 1 further includes a cylindrical conductor (eddy current damping portion) 300. The cylindrical conductor 300 generates eddy currents to damp vibrations in order to obtain strong vibrations (vibration acceleration) over a wide frequency band.

[0415] Specifically, the vibration actuator 1N has a pair of magnets 52, 54, yokes 62, 64, 66, a movable body 60 having a shaft 76 and sleeves 72, 74, and a fixed body having coils 32, 34, 36.

[0416] The pair of magnets 52, 54 are arranged with their magnetic poles facing each other in the axial direction, sandwiching a central yoke 62 therebetween and being sandwiched between yokes 64, 66. A shaft 76 is inserted axially through the pair of magnets 52, 54. A pair of sleeves 72, 74 are inserted into both ends 762, 764 of the shaft 76, respectively.

[0417] The coils 32, 34, and 36 are provided on the bobbin 40, surround the pair of magnets 52 and 54 in a direction perpendicular to the axial direction (radial direction), and are disposed radially opposite the yokes 62, 64, and 66. The bobbin 40 accommodates the movable body 60 inside the coils 32, 34, and 36 via a pair of elastic units 80 so that the movable body 60 can reciprocate in the axial direction, and a cylindrical conductor 300 is attached to surround the movable body 60.

[0418] The pair of sleeves 72, 74 fit into both end portions 762, 764 of the shaft 76, restricting and holding the pair of magnets 52, 54 against axial movement, and fastening the pair of elastic units 80, respectively.

[0419] <Cylindrical conductor (eddy current damping portion) 300> The cylindrical conductor 300 is a cylindrical body made of a conductive material, and is fixed to the inner peripheral surface 42a of the bobbin 40 in the coil assembly 26, and is the coils 32, 34, 36 that surround the magnets 52, 54. The cylindrical conductor 300 generates eddy currents in association with the movement of the movable body 60, i.e., the movement of the magnets 52, 54. The cylindrical conductor 300 damps the movement of the movable body 60 due to the interaction between the generated eddy currents and the magnetic fields of the magnets 52, 54.

[0420] The cylindrical conductor 300 is arranged by being adhered to the inner circumferential surface 42a of the bobbin 40 (more specifically, the bobbin body 42). The cylindrical conductor 300 is arranged at a position facing the magnets 52, 54 with respect to the movable body 60 and closest to the magnets 52, 54 in the radial direction.

[0421] The cylindrical conductor 300 is made of a conductive material, preferably a material with high conductivity, such as copper, aluminum, or an alloy containing these. The cylindrical conductor 300 is formed, for example, from a copper plate processed into a cylindrical shape. The cylindrical conductor 300 damps the vibration of the movable body by interacting with the magnetic fields of the magnets 52 and 54, as described below.

[0422] Specifically, when a current flows through the coils 32, 34, and 36, the movable body 60 moves in the vibration direction due to the force it receives from the magnetic fields of the magnets 52 and 54. At this time, a change in the magnetic flux occurs in the cylindrical conductor 300, and an eddy current is generated in the cylindrical conductor 300 so as to cancel out the change in the magnetic flux.

[0423] The eddy currents generate a force acting in a direction that damps the movement of the movable body 60 due to the Lorentz force, due to interaction with the magnetic fields of the magnets 52 and 54. As a result, the vibration of the movable body 60 is damped.

[0424] In this way, the cylindrical conductor 300 has a braking function that uses the eddy currents that are generated when the movable body 60 is driven to brake the movement of the movable body 60. This braking, that is, the damping of the vibration of the movable body 60, can be set by the distance between the cylindrical conductor 300 and the magnets 52, 54, the area of ​​the cylindrical conductor 300, and the thickness of the cylindrical conductor 300.

[0425] In this magnetic circuit, when current is applied to the coils 32, 34, and 36, magnetic flux flows through the magnets 52, 54 and the coils 32, 34, and 36, and eddy currents are generated in the cylindrical conductor 300, which suppress the flow of magnetic flux from the magnets 52, 54 and damp the vibration of the movable body 60.

[0426] 19, vibration actuator 1N generates a Lorentz force in the -f direction, in other words, a thrust force in the F direction on movable body 60. At this time, cylindrical conductor (eddy current damping portion) 300 interacts with the magnetic fields of magnets 52 and 54 to generate eddy currents, forming a magnetic field in a direction that inhibits the generation of Lorentz force in the -f direction.

[0427] Furthermore, energizing the coils 32, 34, and 36 generates a thrust force in the -F direction (see FIG. 19) on the movable body 60. At this time, the cylindrical conductor (eddy current damping unit) 300 interacts with the magnetic fields of the magnets 52 and 54 to generate eddy currents, forming a magnetic field that inhibits the generation of Lorentz force in the f direction. The vibration actuator 1N damps the vibration of the movable body caused by eddy currents using the cylindrical conductor 300. Since greater damping is applied where acceleration is high, the acceleration peak at the resonance point is suppressed.

[0428] The vibration actuator 1N includes a cylindrical conductor 300 that uses eddy currents generated as the movable body 60 vibrates (moves) to reciprocate the movable body 60, which is made up of coils 32, 34, 36 and magnets 52, 54, i.e., that damps and brakes the vibration. By damping the vibration of the movable body 60, it is possible to smooth out changes in vibration acceleration near the resonance frequency F0, allowing the vibration actuator 1N to obtain strong vibrations (vibration acceleration) over a wide range of drive frequencies. Therefore, even when miniaturized, it is possible to generate suitable high-output vibrations with high vibration expression over a wide range of drive frequencies.

[0429] (Another Modification 2) FIG. 58 is a perspective cross-sectional view showing the main configuration of another modification 2 of the vibration actuator, and FIG. 59 is a perspective cross-sectional view of the coil assembly in the vibration actuator of FIG. 58 with the movable body removed.

[0430] In the vibration actuator 1P of the second modified example, when the same components as those in the vibration actuator 1N of the first modified example are configured, the same names and symbols are used and the description thereof is omitted.

[0431] In the vibration actuator 1P, the cylindrical conductor 300 serving as the eddy current damping section in the vibration actuator 1N is made up of a plurality of divided bodies 322, 324, 326, which are arranged inside the coils 32, 34, 36, in other words, on the outer peripheral surface of the bobbin 40.

[0432] Divided bodies 322, 324, and 326 are each made of a conductive material, such as a copper cylindrical body, and constitute cylindrical conductor 320 surrounding magnets 52 and 54. Divided body 322 is disposed on the bottom surface of recess 40a where a coil is attached between intermediate flanges 43 and 44 of bobbin 40P, which has the same basic configuration as bobbin 40.

[0433] The divided body 324 is disposed on the bottom surface of the recess 40b between the upper flange 45 and the intermediate flange 43 of the bobbin 40P, and the divided body 326 is disposed on the bottom surface of the recess 40c between the intermediate flange 44 and the lower flange 46 of the bobbin 40P.

[0434] In the recesses 40a, 40b, and 40c, the coils 32, 34, and 36 are arranged on the divided bodies 322, 324, and 326. The divided bodies 322, 324, and 326 are conductive members, but the coils 32, 34, and 36 are not electrically connected to the divided bodies 322, 324, and 326 because their outer peripheries are covered with insulating material.

[0435] The multiple divided bodies 322, 324, 326 are arranged to surround the movable body 60 radially outside the magnets 52, 54, more specifically, radially outside the yokes 62, 64, 66 through which the magnetic flux from the magnets 52, 54 passes.

[0436] The multiple divided bodies 322, 324, 326 are arranged with their respective inner circumferential surfaces facing the outer circumferential surface of the movable body 60, particularly the outer surfaces of the yokes 62, 64, 66 that sandwich the magnets 52, 54. With this configuration, as with the vibration actuator 1N of the other modified example 1 of the first embodiment, eddy currents are generated, and the interaction between the generated eddy currents and the magnets 52, 54 can damp the vibration of the movable body 60.

[0437] (Another Modification 3) Figure 60 is a perspective cross-sectional view showing the main configuration of another modification 3 of the vibration actuator, and Figure 61 is a perspective cross-sectional view of the coil assembly in the vibration actuator of Figure 60 with the movable body removed.

[0438] In vibration actuator 1Q of another modified example 3, when the components have the same functions as those in vibration actuator 1N, the same names and symbols are used and the explanation is omitted. Furthermore, components that have almost the same functions are explained by the same names and symbols with the letter "Q" added to the end.

[0439] In vibration actuator 1Q, cylindrical conductor 300 serving as an eddy current damping portion in actuator unit 20P of vibration actuator 1P is formed as cylindrical pseudo conductors 342, 344, 346 using coil wire similar to the coil wire forming coils 32, 34, 36.

[0440] The coil assembly 26Q of the vibration actuator 1Q has recesses 40a, 40b, and 40c formed in the bobbin 40Q between the intermediate flanges 43 and 44, the upper flange 45, the lower flange 46, and the bobbin body 42. The recesses 40a, 40b, and 40c function as coil mounting portions for mounting the coils 32, 34, and 36.

[0441] Pseudo conductors 342, 344, and 346, which are cylindrical bodies formed by winding coil wire, are disposed at the bottoms of the recesses 40a, 40b, and 40c. That is, cylindrical pseudo conductors 342, 344, and 346 are disposed within the recesses 40a, 40b, and 40c, respectively, and coils 32, 34, and 36 are disposed radially outward of these pseudo conductors 342, 344, and 346. The pseudo conductors 342, 344, and 346 are not electrically connected to the coils 32, 34, and 36 because the outer periphery of the coil wire, which is a conductive member, is coated with an insulating material. The pseudo conductors 342, 344, and 346 form a cylindrical conductor 340 on the outer surface of the bobbin body 42 of the bobbin 40Q and inside the coil 30.

[0442] Both ends of the coil wires forming the pseudo conductors 342, 344, and 346 are wound around terminal winding sections (not shown) exposed to the outside, which are separate from and independent of the terminal winding sections of the drive coils. This causes the pseudo conductors 342, 344, and 346 to be short-circuited, and they function as conductors that generate eddy currents.

[0443] With this configuration, as with the other variant 1, eddy currents are generated, and the vibration of the movable body 60 can be damped by the interaction between the generated eddy currents and the magnets 52, 54, and since it is made of coil wire, costs can be reduced without using any other materials.

[0444] In vibration actuator 1Q having pseudo conductors 342, 344, and 346, the change in vibration acceleration near the resonance frequency can be made more gradual compared to a vibration actuator that does not have pseudo conductors.

[0445] (Another Variation 4) Figure 62 is a perspective cross-sectional view showing the main configuration of another variation 4 of the vibration actuator, and Figure 62 is a perspective cross-sectional view of the coil assembly in the vibration actuator of Figure 63 with the movable body removed.

[0446] In the vibration actuator 1R of the other modified example 4, when the components have the same functions as those in the vibration actuator 1N of the other modified example 1, the same names and symbols are used and the explanation is omitted. Components with the same names are basically made of the same materials. Furthermore, components with almost the same functions are explained by using the same names and symbols with "R" added to the end.

[0447] Instead of the cylindrical conductor 300 as the eddy current damping portion in the vibration actuator 1N, outer divided bodies 352, 354, 356, which are a plurality of cylindrical conductive conductors, are provided on the outside of the coils 32, 34, 36.

[0448] In a coil assembly 26R of a vibration actuator 1R of another modified example 4, recesses 40a, 40b, 40c are formed in the bobbin 40 by intermediate flanges 43, 44, upper and lower flanges 45, 46, and the bobbin body 42.

[0449] Coils 32, 34, 36 are disposed within the recesses 40a, 40b, 40c, and outer divided bodies 352, 354, 356 are disposed so as to radially cover the coils 32, 34, 36. The outer divided bodies 352, 354, 356 are not electrically connected to the coils 32, 34, 36 because the outer periphery of the coil wire, which is a conductive member, is covered with an insulating material.

[0450] According to this configuration, as in the first embodiment, eddy currents are generated, and the vibration of the movable body 60 can be damped by the interaction between the generated eddy currents and the magnets 52 and 54 .

[0451] (Another Modification 5) FIG. 64 is a perspective cross-sectional view showing the main configuration of another modification 5 of the vibration actuator, and FIG. 65 is a perspective cross-sectional view of the coil assembly in the vibration actuator of FIG. 64 with the movable body removed.

[0452] When vibration actuator 1S has the same functions as components in vibration actuator 1N of variation 1, the same names and symbols are used and their explanations are omitted. Components with the same names are basically made of the same materials. Components with roughly the same functions are explained by using the same names and symbols with "S" added to the end.

[0453] As shown in another vibration actuator 1S, the cylindrical conductor 300 serving as the eddy current damping portion of the vibration actuator 1N may be configured from a plurality of divided conductors 362, 364, and 366.

[0454] The vibration actuator 1S has divided conductors 362, 364, and 366 in a coil assembly 26S that houses a movable body 60, and the divided conductors 362, 364, and 366 are attached to the inner circumferential surface 42a of the coil main body 42. Like the coil assembly 26, the coil assembly 26S has coils 32, 34, and 36 and a bobbin 40, and further has a plate-shaped conductor 360 consisting of the divided conductors 362, 364, and 366.

[0455] The divided conductors 362, 364, 366 are plate-like bodies extending in the vibration direction, and are arranged on the inner peripheral surface 42a by being divided into multiple pieces in the circumferential direction. The divided conductors 362, 364, 366 are each formed from the same material as the cylindrical conductor 300. The divided conductors 362, 364, 366 are each arranged to extend in the vibration direction, and the divided conductors 362, 364, 366 are arranged facing each other across the entire inner peripheral surface so as to surround the outer peripheral surface of the movable body 60.

[0456] According to this configuration, as in the first embodiment, eddy currents are generated, and the vibration of the movable body 60 can be damped by the interaction between the generated eddy currents and the magnets 52 and 54 .

[0457] (Another Modification 6) Figure 66 is a perspective cross-sectional view showing the main configuration of another modification 6 of the vibration actuator, and Figure 67 is a perspective cross-sectional view of the coil assembly in the vibration actuator of Figure 66 with the movable body removed.

[0458] When vibration actuator 1T has the same functions as components in vibration actuator 1N of variation 1, the same names and symbols are used and their explanations are omitted. Components with the same names are basically made of the same materials. Furthermore, components with roughly the same functions are explained by using the same names and symbols with the letter "T" added to the end.

[0459] As shown in another vibration actuator 1T, the cylindrical conductor 300 serving as the eddy current damping portion of the vibration actuator 1N may be configured from a plurality of divided conductors 372, 374.

[0460] The plurality of divided conductors 372, 374 are rectangular tubular, and are arranged in the vibration direction by dividing them into a plurality of parts to form a tubular conductor 370 as an eddy current damping portion.

[0461] The divided conductors 372, 374 are attached in the circumferential direction to the inner peripheral surface 42a of the bobbin main body 42 and are divided into multiple pieces in the vibration direction. The divided conductors 372, 374 are each made of the same material as the cylindrical conductor 300. The divided conductors 372, 374 are each aligned uniformly in the vibration direction to form the cylindrical body 370.

[0462] The divided conductors 372, 374 are arranged facing each other, with the entire inner circumferential surface surrounding the outer circumferential surface of the movable body 60. With this configuration, as with the first modified example, eddy currents are generated, and the vibration of the movable body 60 can be damped by the interaction between the generated eddy currents and the magnets 52, 54.

[0463] (Another Variation 7) Figure 68 is a perspective cross-sectional view showing the main configuration of another variation 7 of the vibration actuator, and Figure 69 is a perspective cross-sectional view of the coil assembly in the vibration actuator of Figure 68 with the movable body removed.

[0464] When the vibration actuator 1U has the same functions as the components in the vibration actuator 1N of Modification 1, the same names and symbols are used and the explanations are omitted. Note that components with the same names are basically made of the same materials.

[0465] As shown in another vibration actuator 1U, the cylindrical conductor 300 serving as the eddy current damping portion of the vibration actuator 1N may be formed integrally with the bobbin 40U. In the vibration actuator 1U, the cylindrical main body 42 of the bobbin 40U that holds the coils 32, 34, 36 is formed by inserting and molding a plurality of cylindrical conductive members 382, ​​384, 386 that become the cylindrical conductor 380.

[0466] Here, the conductive members 382, ​​384, 386 are insert molded so as to become the bottom surfaces of the recesses 40a, 40b, 40c of the bobbin 40U.

[0467] Conductive members 382, ​​384, 386 are arranged facing each other, with the entire inner circumferential surface surrounding the outer circumferential surface of movable body 60. With this configuration, as with the first modified example, eddy currents are generated, and the vibration of movable body 60 can be damped by the interaction between the generated eddy currents and magnets 52, 54.

[0468] (Electronic Device) Figures 70 and 71 are diagrams showing examples of mounting forms of the vibration actuator 1. Figure 70 shows an example in which the vibration actuator 1 is mounted on a game controller GC, and Figure 71 shows an example in which the vibration actuator 1 is mounted on a mobile terminal M.

[0469] The game controller GC is connected to the game console via wireless communication, for example, and is used by being held or grasped by the user. The game controller GC here has a rectangular plate shape, and is operated by the user grasping the left and right sides of the game controller GC with both hands.

[0470] The game controller GC notifies the user of commands from the game console by vibration. Although not shown, the game controller GC also has functions other than command notification, such as an input operation unit for the game console.

[0471] The mobile terminal M is, for example, a mobile communication terminal such as a mobile phone or a smartphone, or a wearable terminal having these functions. The mobile terminal M notifies the user of an incoming call from an external communication device by vibration, and also realizes each function of the mobile terminal M (for example, a function that provides a sense of operation or a sense of presence).

[0472] 70 and 71 , the game controller GC and the mobile terminal M each have a communication unit 201, a processing unit 202, a drive control unit 203, and vibration actuators 204, 205, and 206, which are vibration actuators 1 serving as drive units. Note that the game controller GC is equipped with a plurality of vibration actuators 204, 205. Furthermore, these vibration actuators 204, 205, and 206 may be vibration actuators of any of the embodiments and modified examples other than the vibration actuator 1.

[0473] In the game controller GC and the portable terminal M, the vibration actuators 204, 205, and 206 are preferably mounted so that the surface (the bottom surface of the bottom surface portion 124) perpendicular to the vibration direction of the vibration actuators 204, 205, and 206 is parallel to the main surface of the terminal. The main surface of the terminal is the surface that comes into contact with the surface of the user's body, and in this embodiment, it means the vibration transmission surface that comes into contact with the surface of the user's body and transmits vibrations. Note that the main surface of the terminal and the bottom surface of the bottom surface portion 124 of the vibration actuators 204, 205, and 206 may be arranged so that they are perpendicular to each other.

[0474] Specifically, in the game controller GC, vibration actuators 204 and 205 are mounted so that their vibration direction is perpendicular to the surface that comes into contact with the fingertips, finger pads, or back of the hand of the operating user, or the surface on which the operation unit is provided. Also, in the case of the portable terminal M, vibration actuator 206 is mounted so that its vibration direction is perpendicular to the display screen (touch panel surface). As a result, vibrations in a direction perpendicular to the main surfaces of the game controller GC and portable terminal M are transmitted to the user.

[0475] The communication unit 201 is connected to an external communication device via wireless communication, receives signals from the communication device, and outputs the signals to the processing unit 202. In the case of a game controller GC, the external communication device is a game console main body as an information communication terminal, and communication is performed in accordance with a short-range wireless communication standard such as Bluetooth (registered trademark). In the case of a portable terminal M, the external communication device is, for example, a base station, and communication is performed in accordance with a mobile communication standard.

[0476] The processing unit 202 converts the input signal into a drive signal for driving the vibration actuators 204, 205, and 206 using a conversion circuit unit (not shown), and outputs the drive signal to the drive control unit 203. In the mobile terminal M, the processing unit 202 generates the drive signal based on the signal input from the communication unit 201 as well as signals input from various functional units (not shown, for example, an operation unit such as a touch panel).

[0477] The drive control unit 203 is connected to the vibration actuators 204, 205, and 206, and is equipped with circuits for driving the vibration actuators 204, 205, and 206. The drive control unit 203 supplies drive signals to the vibration actuators 204, 205, and 206.

[0478] The vibration actuators 204, 205, and 206 are driven in accordance with drive signals from the drive control unit 203. Specifically, in the vibration actuators 204, 205, and 206, the movable body 60 vibrates in a direction perpendicular to the main surfaces of the game controller GC and the mobile terminal M.

[0479] The movable body 60 may be configured to come into contact with the bracket 14, which is the top plate, or the bottom surface 124 via the damping material 88 each time it vibrates. In this case, the impact on the bracket 14 or the bottom surface 124 caused by the vibration of the movable body 60, i.e., the impact on the housing, is transmitted directly to the user as vibration. In particular, since the game controller GC is equipped with multiple vibration actuators 204, 205, one or both of the multiple vibration actuators 204, 205 can be driven simultaneously in accordance with the input drive signal.

[0480] The user can be given a sufficient bodily sensation of vibration because vibrations are transmitted in a direction perpendicular to the body surface to the surface of the user's body that is in contact with the game controller GC or the mobile terminal M. The game controller GC can impart bodily sensation of vibration to the user by one or both of the vibration actuators 204, 205, and can impart highly expressive vibrations, such as selectively imparting at least strong and weak vibrations.

[0481] The invention made by the inventor has been specifically described above based on an embodiment, but the present invention is not limited to the above embodiment and can be modified within the scope of the gist thereof.

[0482] Furthermore, the vibration actuator according to the present invention is suitable for application to portable devices (for example, portable information terminals such as tablet PCs, portable game terminals, and wearable devices worn by the user) other than the game controller GC and portable terminal M. Furthermore, in addition to the portable devices described above, the vibration actuator 1 of this embodiment can also be used in electric beauty and hairdressing appliances that require vibration, such as facial massagers.

[0483] The embodiments of the present invention have been described above. Note that the above description is an example of a preferred embodiment of the present invention, and the scope of the present invention is not limited to this. In other words, the description of the configuration of the above device and the shape of each part is one example, and it is clear that various modifications and additions to these examples are possible within the scope of the present invention.

[0484] The disclosures of the specifications, drawings and abstracts contained in Japanese Patent Application No. 2024-045317 filed on March 21, 2024 and Japanese Patent Application No. 2024-112551 filed on July 12, 2024 are incorporated herein by reference in their entirety.

[0485] The vibration actuator according to the present invention can be miniaturized while suitably generating vibrations, and is therefore useful for use in electronic devices.

[0486] 1, 1E, 1H, 1J, 1K, 100, 204, 205, 206 vibration actuator, 10 case, 12 case body, 14 bracket, 16 conductive board, 20, 20a, 20E, 20F, 20G, 20J, 20K, 20L, 20M, 20N, 20P actuator unit, 22, 22M, 24, 24M end spacer, 23 inclined side portion, 26, 26E, 26H, 26Q, 26R, 26S coil assembly, 30 coil, 32, 32H central coil, 34 upper coil, 36 lower coil, 40, 40E, 40H, 40P, 40Q, 40U bobbin, 40a, 40b, 40c recess, 42, 42H, Bobbin body, 42a: inner peripheral surface, 43, 44: intermediate flange, 45: upper flange, 46: lower flange, 47: terminal lead-out portion, 48: connection terminal, 49: opening, 50, 52, 54: magnet, 52a, 54a: surface, 60, 600: movable body, 60a: outer peripheral surface, 62: central yoke (first yoke), 64, 640: upper yoke (second yoke), 66, 660: lower yoke (second yoke), 72, 74, 720, 740: sleeve, 76: shaft, 77, 78: spring stop member (fastening member), 80, 80L, 80M, 81, 81B, 81C, 82, 82A: elastic unit (elastic body), 88, 88A, 88B, 88C: damping material, 90, 91, 92 Electromagnetic shielding section (magnetic shielding section), 122 peripheral wall section, 124 bottom surface section, 201 communication section, 202 processing section, 203 drive control section, 400 central opening section, 432, 442, 817, 4522, 4622 notch section, 452, 462 opening edge section, 480 leg section, 522, 542, 622, 642, 662, 702, 704, 722, 742, 812 through hole, 640a upper surface, 762, 764 both ends, 772, 782 insertion section, 774, 784 flange, 802, 802L, 804, 804L leaf spring, 806 spring holder, 807, 809 protrusion section, 808, 810 Collar portion, 814 Inner peripheral portion, 815 Outer peripheral portion, 816 Deformed arm portion, 882 Opening

Claims

1. A vibration actuator comprising: a movable body having a plurality of magnets arranged in pairs with the same magnetic poles facing each other in the axial direction, the movable body having a rectangular cross section perpendicular to the axial direction; and a fixed body having a rectangular coil surrounding the magnets in a direction perpendicular to the axial direction and a rectangular cylindrical protective wall portion arranged between the coil and the magnets, the fixed body containing the movable body inside the protective wall portion via an elastic body so that it can move back and forth in the axial direction.

2. A vibration actuator as described in claim 1, having a restricting protrusion formed on a part of the inner peripheral surface of the protective wall portion, which makes point or line contact with the movable body to restrict the reciprocating movement of the movable body to along the axis when the reciprocating movement direction of the movable body deviates.

3. A vibration actuator according to claim 2, wherein the restricting protrusions are formed symmetrically on opposing inner circumferential surfaces of the protective wall portion.

4. The vibration actuator according to claim 1, wherein the protective wall portion has an opening that allows a portion of the coil to face the movable body.

5. The vibration actuator according to claim 1, further comprising a magnetic shield disposed on the outer periphery of the protective wall so as to surround the coil.

6. A vibration actuator according to claim 5, wherein the magnetic shield portion is positioned so that its axial center faces the axial center of the coil, and the axial length of the magnetic shield portion is shorter than the axial length of the coil.

7. A vibration actuator according to claim 5, wherein the magnetic shielding portion is a rectangular cylinder having openings penetrating in the radial direction at each of the corners symmetrically positioned about the central axis.

8. A portable or wearable electrical device incorporating the vibration actuator according to claim 1.

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