Vibration actuator and electrical device

Abstract

To drive a vibration actuator with preferable vibration output capable of being manufactured with high dimensional accuracy while achieving reduction in size.SOLUTION: A vibration actuator includes: a movable body, in which a pair of annular yokes having a discoid magnet, and having openings in a center on a surface and a rear face in an axial direction of the magnet, and a pair of weight parts having through holes continuous with the openings in the axial direction are respectively laminated and arranged, and in the continuous openings and the through holes, other ends of connection parts connecting a pair of elastic support parts on one end side are respectively arranged; and a fixed body having a cylindrical part storing the movable body, supporting the movable body so as to allow reciprocating vibration in the axial direction by the pair of elastic support parts, and having a pair of annular coils arranged outside a radial direction of the movable body. The movable body is vibrated in the axial direction by energizing the coils.SELECTED DRAWING: Figure 3

Description

[Technical Field]

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

[0002] Conventionally, electronic devices with vibration functions are equipped with vibration actuators as vibration generation sources. By driving the vibration actuators and transmitting vibrations to the user, electronic devices can provide stimuli, notify users of incoming calls, and improve the sense of operation and realism. Electronic devices are primarily handheld electrical devices, including game console controllers (gamepads), mobile communication devices such as smartphones, and mobile information terminals such as tablet PCs. Vibration actuators are also sometimes installed in wearable devices that are attached to clothing or the arm.

[0003] As a vibration actuator having a structure that can be miniaturized and mounted in a portable device, for example, as shown in Patent Document 1, a vibration actuator used in a pager or the like is known.

[0004] This vibration actuator has a pair of elastic plates arranged facing each other and supported by the opening edges of a cylindrical frame. In addition, this vibration actuator has a yoke with a magnet attached fixed to the raised central portion of one of the pair of elastic plates, which has a spiral shape, and the yoke is supported within the frame.

[0005] The yoke and the magnet form a ring-shaped magnetic field generator, and the coil is attached to the other elastic plate and placed within the magnetic field of this magnetic field generator. By alternately applying currents of different frequencies to the coils through an oscillator circuit, the pair of elastic plates are selectively resonated to generate vibrations, and the yoke vibrates within the frame in the direction of the frame's centerline. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 3748637 Summary of the Invention [Problem to be solved by the invention]

[0007] Incidentally, as the products in which they are installed become smaller, it is desired that vibration actuators as vibration generators be made smaller while still maintaining high output. In Patent Document 1, a yoke as a movable body is supported from one side in the vibration direction via a plate-shaped elastic body within a frame body as a fixed body, and a coil placed on the other side is placed in a recess in the yoke and faces the magnet in the radial direction.

[0008] Therefore, when miniaturizing the actuator, the assembly process is complicated and time-consuming, and there is also the problem of the vibration output of the vibration actuator.

[0009] Furthermore, in order to obtain a suitable vibration output in a miniaturized vibration actuator, it is desirable that the movable body be formed with high precision so that it vibrates in a set vibration direction, and that its mass be easily adjusted to ensure the desired vibration output.

[0010] The present invention has been made in view of the above points, and has as its object to provide a vibration actuator and an electrical device that can be manufactured with high dimensional accuracy while being miniaturized and that is driven with a suitable vibration output. [Means for solving the problem]

[0011] One aspect of the vibration actuator of the present invention is The magnet has a disk-shaped magnet with no through-holes, and a pair of annular yokes with an opening in the center and a pair of weights with through-holes that are continuous with the openings in the axial direction are stacked on the front and back surfaces of the magnet, and a pair of elastic support parts are connected at one end to the continuous openings and through-holes. a paira movable body arranged such that the other end of the connecting portion faces the front and back surfaces of the magnet, respectively; a fixed body having a cylindrical portion that accommodates the movable body, the fixed body being supported by the pair of elastic support portions so that the movable body can vibrate back and forth in the axial direction, and the fixed body having a pair of annular coils that are arranged radially outside the movable body; and the pair of annular yokes, the pair of weight portions, and the pair of connecting portions are provided symmetrically with respect to the magnet on both sides in the vibration direction of the magnet, The movable body is vibrated in the axial direction by energizing the coil.

[0012] One aspect of the electrical device of the present invention is A handheld or wearable electrical device, The vibration actuator having the above-described configuration is mounted on the part that comes into contact with the user. [Effects of the Invention]

[0013] According to the present invention, it is possible to manufacture a motor with high dimensional accuracy while achieving miniaturization, and it is possible to drive the motor with a suitable vibration output. [Brief explanation of the drawings]

[0014] [Figure 1] 1 is a perspective view of the appearance of a vibration actuator according to an embodiment of the present invention, as viewed from the front side; [Figure 2] 1 is an external perspective view of a vibration actuator according to an embodiment of the present invention, as viewed from the rear side; [Figure 3] FIG. 2 is a longitudinal sectional view of the vibration actuator. [Figure 4] FIG. 2 is a view showing the vibration actuator with the case and the drive unit therein disassembled. [Figure 5] FIG. 2 is an external perspective view of a drive unit. [Figure 6] FIG. 2 is an exploded perspective view of the drive unit showing a coil holding portion, a movable body, and an elastic support portion. [Figure 7] FIG. 2 is a perspective view of a movable body to which an elastic support portion is attached. [Figure 8]FIG. 2 is an exploded perspective view of a movable body to which an elastic support portion is attached. [Figure 9] 10 is a view showing the outer surface of the coil assembly in the drive unit with the outer yoke removed from the coil assembly. FIG. [Figure 10] 10 is a diagram showing a state in which the coil is removed from the coil holding portion in the coil assembly. FIG. [Figure 11] FIG. 2 is a bottom perspective view of the outer yoke. [Figure 12] FIG. 2 is a perspective view of the top surface side of the case body. [Figure 13] FIG. [Figure 14] FIG. 2 is a diagram schematically illustrating a magnetic circuit configuration of the vibration actuator. [Figure 15] FIG. 10 is a diagram illustrating the operation of the actuator body, showing a vibration state in which the movable body is at a first amplitude position on the top surface side. [Figure 16] FIG. 10 is a diagram illustrating the operation of the actuator body, showing a vibration state in which the movable body is at a second amplitude position on the top surface side. [Figure 17] FIG. 10 is a diagram illustrating the operation of the actuator body, showing a vibration state in which the movable body is at a first amplitude position on the bottom side. [Figure 18] FIG. 10 is a diagram illustrating the operation of the actuator body, showing a vibration state in which the movable body is at a second amplitude position on the bottom side. [Figure 19] 5A and 5B are diagrams schematically showing the magnetic balance of the vibration actuator of the present embodiment in a non-vibration state. [Figure 20] FIG. 10 is a diagram showing the magnetic balance of a vibration actuator in a non-vibration state as a comparative example. [Figure 21] Figures 21A and 21B are figures used to explain the operation of a vibration actuator as a comparative example, where Figure 21A is a figure showing a vibration state in which the movable body is at a first amplitude position on the top surface side, and Figure 21B is a figure showing a vibration state in which the movable body is at a second amplitude position on the top surface side. [Figure 22] 1 is a diagram showing an example of an electrical device in which a vibration actuator according to an embodiment of the present invention is mounted. [Figure 23] 1 is a diagram showing an example of an electrical device in which a vibration actuator according to an embodiment of the present invention is mounted. DETAILED DESCRIPTION OF THE INVENTION

[0015] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0016] [Overall configuration of vibration actuator] FIG. 1 is a perspective view of a vibration actuator according to an embodiment of the present invention, as seen from the front, and FIG. 2 is a perspective view of a vibration actuator according to an embodiment of the present invention, as seen from the rear. FIG. 3 is a longitudinal cross-sectional view of the vibration actuator. FIG. 4 is a view of the vibration actuator, with the case and the drive unit therein disassembled. Note that the terms "upper" and "lower" in this embodiment are used for the sake of convenience and ease of understanding, and refer to one side and the other in the vibration direction of the movable body in the vibration actuator. In other words, when the vibration actuator is mounted in an electrical device (see FIGS. 22 and 23), it does not matter if it is mounted upside down or left and right.

[0017] The vibration actuator 1 is mounted as an electrical device as a vibration generating source in electronic devices such as portable game terminal devices (for example, the game controller GC shown in FIG. 22) 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. 23). 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.

[0018] 1 and 2, the vibration actuator 1 is a vibrating body having an overall cylindrical case 10. Both end faces of the case 10 in the axial direction (vibration direction) are formed in a convex shape, and the center of the end faces is formed in a flat shape.

[0019] 3 and 4, in this embodiment, case 10 is a hollow cylindrical body including a cylindrical case body 11 with a bottom and a lid portion 12. A detailed description of case 10 will be given later.

[0020] As shown in Figures 3 and 4, the vibration actuator 1 is constructed by housing a drive unit 15 having a vibrating movable body 20 inside a case 10. When the movable body 20 moves, the vibration actuator 1 itself functions as a vibrating body. In this embodiment, the drive unit 15 is cylindrical as a whole, and its central axis (not shown) is parallel to or coaxial with the central axis (not shown) of the case 10, which is also cylindrical. In this embodiment, the vibration direction of the movable body 20 is a linear direction that extends along the direction of the central axis of the cylindrical drive unit 15 and includes the F direction and the -F direction (see Figure 14).

[0021] The vibration actuator 1 has a movable body 20 having a magnet 21, a first yoke 23 and a second yoke 25, a fixed body 40 having a coil (a pair of coils 61, 62), and plate-shaped elastic support members 81, 82 that support the movable body 20 so that it can move back and forth relative to the fixed body 40.

[0022] Fig. 5 is an external perspective view of the drive unit 15, specifically, a perspective view seen from the terminal binding portion side. Fig. 6 is an exploded perspective view of the drive unit showing the coil holding portion, the movable body, and the elastic support portion.

[0023] 3 to 6 includes a coil holding portion 42, an outer yoke 50, a movable body 20, and elastic support portions 81 and 82. Coil holding portion 42, together with coils 61 and 62, constitutes a coil assembly that is part of a fixed body, and the coil assembly, together with outer yoke 50, is part of the fixed body. Drive unit 15 supports movable body 20, which is disposed within coil holding portion 42, in a vibrating state while suspended from coil holding portion 42 via elastic support portions 81 and 82 that are disposed opposite and spaced apart in the axial direction (vibration direction).

[0024] The drive unit 15 is connected to an external device via its outer circumferential surface, in other words, the terminal binding portion (wire connection portion) 43 exposed on the outer circumferential surface of the coil holding portion 42, and receives power from the external device.

[0025] <Movable body 20> 3 and 6, the movable body 20 is arranged inside the cylindrical coil holding portion 42 of the fixed body 40 with a gap therebetween in the circumferential direction. The movable body 20 is columnar, and both ends (upper and lower ends) that are spaced apart in the axial direction, i.e., the vibration direction, are connected to the inner peripheries of the elastic support members 81 and 82. The elastic support members 81 and 82 are attached so as to cover both openings of the cylindrical coil holding portion 42. The movable body 20 is supported so as to be reciprocally movable in the axial direction along the inner circumferential surface 42a of the coil holding portion 42.

[0026] FIG. 7 is a perspective view of the movable body to which the elastic support members are attached, and FIG. 8 is an exploded perspective view of the movable body to which the elastic support members are attached.

[0027] As shown in Figures 3 and 6 to 8, the movable body 20 has a magnet 21, a pair of movable body yokes (e.g., a first yoke 23 and a second yoke 25), a pair of weight portions (weight portion 27, weight portion 29), and a pair of connecting portions (a first connecting portion 31, a second connecting portion 33).

[0028] In this embodiment, magnet 21 is disposed in the center of movable body 20 in the vibration direction, that is, at the center of movable body 20. On both sides of magnet 21 in the vibration direction (front surface 21a side and back surface 21b side, i.e., up and down direction in each drawing), first yoke 23 and second yoke 25, weights 27 and 29, and connecting portions 31 and 33 are provided symmetrically with respect to magnet 21. For example, first yoke 23 and second yoke 25, weights 27 and 29 are connected to both sides of magnet 21 in the vibration direction. Connecting portions 31 and 33 are inserted into and joined to first yoke 23 and weight 27, and second yoke 25 and weight 29, respectively. In the movable body 20, the weights 27, 29 are stacked relative to the magnet 21, the first yoke 23, and the second yoke 25 so that they are positioned so as not to face the outer yoke 50 of the fixed body 40 when the movable body 20 is at the maximum amplitude position in the vibration direction (see FIGS. 16 and 18), and the weights 27, 29 are made of a non-magnetic material. This prevents the expansion of the magnetic circuit configuration of the vibration actuator 1, allowing the magnetic circuit to be configured compactly. Furthermore, because the weights 27, 29 are made of a non-magnetic material that does not affect the size of the magnetic circuit, the design freedom of the weights 27, 29 can be increased in order to obtain desired vibration characteristics for the movable body 20.

[0029] In the movable body 20, the outer peripheral surface 20a of the central portion, specifically the outer peripheral surfaces of the magnet 21, the first yoke 23, and the second yoke 25, are opposed to each other at a predetermined distance inside the inner peripheral surface 42a of the coil holding portion 42.

[0030] <Magnet 21> As shown in FIGS. 6 to 8, the magnet 21 is a solid columnar (plate-like) magnetized in the vibration direction. For example, the magnet 21 has front and back surfaces 21a and 21b that are spaced apart in the vibration direction and have different polarities. In this embodiment, the magnet 21 is formed in a cylindrical shape (which may also be called a disk shape) with a diameter (width) that is longer than the length (height) in the vibration direction. The magnet 21 is, for example, a neodymium sintered magnet.

[0031] The magnet 21 is arranged so as to be spaced apart from the coils (a pair of coils 61, 62) (details of which will be described later) held by the coil holding portion 42, on the radially inner side of the coils (a pair of coils 61, 62). Here, the "radial direction" also refers to a direction perpendicular to the axial direction (vibration direction) of the coils (a pair of coils 61, 62). In other words, the magnet 21 is arranged so as to face the center position in the vibration direction on the inner circumferential surface of the coil holding portion 42, on the radially outer side. The pair of coils 61, 62 will also be referred to as "coils 61, 62" hereinafter.

[0032] This "spacing" in the radial direction is the spacing between magnet 21 and coils 61, 62 when cylindrical main body 422, around which coils 61, 62 are wound, is positioned radially inside coils 61, 62, between coils 61, 62 and magnet 21. This spacing is also set to allow movement without contact with each other in the vibration direction of movable body 20. The "spacing" in the embodiment refers to the predetermined spacing between coil holding portion 42 (particularly cylindrical main body 422) and magnet 21 shown in FIG. 3.

[0033] Magnet 21 may have a shape other than a solid column, such as a cylindrical shape or a plate shape, as long as it is disposed inside coils 61 and 62 with two magnetized surfaces facing in the direction of extension of the axes of coils 61 and 62. In addition, it is desirable that the axial center of magnet 21 coincides with the axial center of movable body 20.

[0034] <First yoke 23 and second yoke 25> The first yoke 23 and the second yoke 25 are made of magnetic material and are fixed to the front and back surfaces 21a and 21b, respectively, of the magnet 21. The first yoke 23 and the second yoke 25 are each formed in an annular shape. The first yoke 23 and the second yoke 25 each have an outer circumferential surface with the same diameter as the magnet 21.

[0035] The first yoke 23 and the second yoke 25, together with the magnet 21, the coil (a pair of coils 61, 62), and the outer yoke 50, constitute the magnetic circuit of the vibration actuator 1. The first yoke 23 and the second yoke 25 concentrate the magnetic flux of the magnet 21, allowing it to flow efficiently without leakage, and effectively distribute the magnetic flux flowing between the magnet 21 and the coil (a pair of coils 61, 62). The first yoke 23 and the second yoke 25 are formed from, for example, SECC (bonded steel plate) or the like.

[0036] In addition to functioning as part of the magnetic circuit, the first yoke 23 and the second yoke 25 may also have the function of serving as the main body of the movable body 20, the function of positioning and fixing the connection parts 31 and 33 relative to the magnet 21, and the function of serving as a weight.

[0037] In this embodiment, the first yoke 23 and the second yoke 25 are formed in the shape of an annular flat plate with the same outer diameter and surface shape as the magnet 21. The first yoke 23 and the second yoke 25 are fixed to the magnet 21 so that their outer peripheral surfaces are flush with the outer peripheral surface of the magnet, and together with the outer peripheral surface of the magnet 21, they form the outer peripheral surface 20a of the movable body 20.

[0038] In this embodiment, the first yoke 23 and the second yoke 25 are the same member, and in this embodiment, they are provided symmetrically on the front and back surfaces 21a, 21b (top and bottom surfaces) of the magnet 21, with the magnet 21 at the center, sandwiching the magnet 21. The first yoke 23 and the second yoke 25 may be fixed by being attracted to the magnet 21, or may be fixed to the magnet 21 by, for example, a thermosetting adhesive such as epoxy resin or an anaerobic adhesive.

[0039] Yoke openings 232 and 252 are provided in the center of the first yoke 23 and the second yoke 25, respectively. The connecting portions 31 and 33 (also referred to as the first connecting portion 31 and the second connecting portion 33) are inserted into the yoke openings 232 and 252. For example, the connecting portions 33 may be fitted into the yoke openings 232 and 252, or may be joined after insertion.

[0040] Yoke openings 232, 252 are provided so that the axes of connecting portions 31, 33, in other words, the central axes of elastic support portions 81, 82 (described later), are aligned with the central axis of movable body 20. Note that yoke openings 232, 252 are formed with dimensions that fit corresponding to the outer shapes of connecting portions 31, 33, but are not limited to this. Yoke openings 232, 252 may contact the outer peripheral surfaces of inserted connecting portions 31, 33 at three or four points, positioned on the axes of movable body 20, and fixedly supported. Also, yoke openings 232, 252 may be formed in a recessed shape rather than penetrating in the axial direction, with connecting portions 31, 33 joined within this recessed shape.

[0041] When the movable body 20 is not vibrating, the first yoke 23 and the second yoke 25 are positioned inside (radially inward) the coils (pair of coils 61, 62) so as to face each of the coils (pair of coils 61, 62) in a direction perpendicular to the axial direction of the coils (pair of coils 61, 62). When the movable body 20 is not vibrating, the first yoke 23 and the second yoke 25 are preferably positioned inside (radially inward) the pair of coils 61, 62 so as to face the center of the vibration direction of the pair of coils 61, 62 in a direction perpendicular to the vibration direction.

[0042] In this embodiment, the first yoke 23 and the second yoke 25 are preferably arranged such that the height position of the upper surface of the first yoke 23 above the magnet 21 is located lower (closer to the center) than the upper end of the upper coil 61. In addition, the height position of the lower surface of the second yoke 25 below the magnet 21 is preferably located higher (closer to the center) than the lower end of the lower coil 62.

[0043] In this way, the first yoke 23 and the second yoke 25, together with the magnet 21, the coils 61, 62, and the outer yoke 50, form a magnetic circuit having a suitable magnetic path with little magnetic flux leakage and high magnetic efficiency.

[0044] <Weight 27, 29> The weights 27 and 29 are provided on the first yoke 23 and the second yoke 25, which sandwich the magnet 21, respectively, so as to sandwich the first yoke 23 and the second yoke 25 therebetween.

[0045] Plummets 27 and 29 are arranged symmetrically in the vibration direction so as to sandwich magnet 21 and first and second yokes 23 and 25 therebetween, and increase the vibration output of movable body 20.

[0046] The weights 27 and 29 are preferably made of a material with a high specific gravity. The weights 27 and 29 are made of a material with a higher specific gravity than the first yoke 23 and the second yoke 25, for example, tungsten (19.3 g / cm 3 The weights 27 and 29 are made of silicon steel plate (the specific gravity of the steel plate is 7.70 to 7.98 g / cm 3 ) and other materials with a higher specific gravity (for example, a specific gravity of 16 to 19 g / cm 3 It is preferable that weights 27, 29 are formed from a material having a thickness of about 1 / 4 mm. For example, tungsten can be used as the material for weights 27, 29. This makes it possible to increase the mass of movable body 20 relatively easily even when the external dimensions of movable body 20 are set in the design, etc., and to achieve the desired vibration output that is a vibration that the user can feel satisfactorily.

[0047] The mass of weights 27 and 29 can be changed by changing the size according to the vibration output of movable body 20. The outer diameters of weights 27, 29 are smaller than the outer diameters of first yoke 23 and second yoke 25. As a result, when movable body 20 vibrates, movable body 20 is less likely to come into contact with elastic support members 81, 82, allowing it to vibrate favorably. This makes it possible to ensure high vibration output while miniaturizing vibration actuator 1.

[0048] The weights 27 and 29 are each formed in an annular shape. The through holes 272 and 292 of the weights 27 and 29 are formed coaxially with and have the same diameter as the yoke openings 232 and 252 of the first yoke 23 and the second yoke 25, but may have different diameters.

[0049] The connecting portions 31 and 33 are inserted into the through holes 272 and 292 of the weight portions 27 and 29.

[0050] Through holes 272, 292, together with yoke openings 232, 252, function as positioning elements for positioning connecting portions 31, 33 at positions coaxial with the axis of movable body 20 when attaching them to a magnet. In the present embodiment, weights 27, 29 are provided one on each of first yoke 23 and second yoke 25, but two or more may be provided one on each. Weights 27, 29 are preferably made of the same material formed in the same way, but may be made of any material having the same function and mass.

[0051] <Connections 31 and 33> The connecting portions 31 and 33 connect the magnet 21, the first yoke 23 and the second yoke 25 to the elastic supporting portions 81 and 82, respectively.

[0052] The connecting portions 31 and 33 constitute the ends of the movable body 20 on both sides in the vibration direction, that is, the ends positioned apart from the magnet 21 on both sides in the vibration direction.

[0053] In this embodiment, the connecting portions 31 and 33 are cylindrical bodies arranged along the central axis of the movable body 20, and are interposed between the first yoke 23 and the second yoke 25 and the elastic support portions 81 and .

[0054] Connection portions 31 and 33 are arranged to protrude from the center of each of front and rear surfaces 21a and 21b of magnet 21, and are inserted into first yoke 23, second yoke 25, and weights 27 and 29. Connection portions 31 and 33 are fixed to first yoke 23, second yoke 25, and weights 27 and 29, respectively. Connection portions 31 and 33 may also be fixed to magnet 21, and are arranged to protrude from weights 27 and 29.

[0055] The connection portions 31, 33 have connection bodies 312, 332 provided on one end side and fixed to the members constituting the movable body 20, and support fixing portions 314, 334 provided on the other end side and attached to the other end of the connection bodies 312, 332.

[0056] The connecting bodies 312, 332 have a shape that allows them to be inserted into the yoke openings 232, 252 of the first yoke 23 and the second yoke 25 and the through holes 272, 292 of the weights 27, 29. In this embodiment, the yoke openings 232, 252 and the through holes 272, 292 have the same diameter, so the connecting bodies 312, 332 are formed in a cylindrical shape that corresponds to the yoke openings 232, 252 and the through holes 272, 292. In this embodiment, the connecting bodies 312, 332 are inserted into the yoke openings 232, 252 and the through holes 272, 292, and are positioned therein, and are then fixed to the magnet 21, the first yoke 23 and the second yoke 25, the weights 27, 29, etc.

[0057] The connection bodies 312, 332 may be fixed to the first yoke 23, the second yoke 25, and the weights 27, 29 by press-fitting. The connection parts 31, 33 may be fixed to the first yoke 23, the second yoke 25, and the weights 27, 29 by adhesive alone or in combination with adhesive using a thermosetting adhesive such as epoxy resin or an anaerobic adhesive.

[0058] The connecting bodies 312, 332 may be joined by abutting against the magnet 21 at the other end face facing the magnet 21. The connecting bodies 312, 332 are arranged so that their central axes coincide with the axis of the movable body 20, and are arranged so as to protrude on both sides in the vibration direction along the axis.

[0059] The support fixing portions 314 and 334 join the movable body 20 to the elastic support portions 81 and 82 via the connection bodies 312 and 332 of the connection portions 31 and 33 .

[0060] The support fixing portions 314, 334 are protruding portions that protrude from the surface of one end of the connection body 312, 332 in the axial direction (vibration direction) and have an outer diameter smaller than the outer diameter of the connection body 312, 332. Incidentally, recesses 316, 336 are provided around these protruding portions. The recesses 316, 336 are annular grooves that surround the support fixing portions 314, 334. The recesses 316, 336 may function as, for example, a reservoir for adhesive or welding material when bonding to the inner peripheries of the elastic support portions 81, 82, or as a portion to be engaged during crimping. In these cases, the recesses 316, 336 can firmly bond the movable body 20 to the elastic support portions 81, 82.

[0061] Specifically, support fixing part 314 constitutes one end of movable body 20 in the vibration direction, i.e., the upper end of movable body 20, and is joined to inner circumferential part 802, which is the end on the inner diameter side of the upper leaf spring, which is elastic support part 81. On the other hand, support fixing part 334 constitutes the other end of movable body 20 in the vibration direction, i.e., the lower end of movable body 20, and is joined to inner circumferential part 802, which is the end on the inner diameter side of the lower leaf spring, which is elastic support part 82.

[0062] When the support and fastening portions 314, 334 are fitted into and joined to the inner circumferential portions 802, 802 of the elastic support portions 81, 82, the peripheral surfaces of the support and fastening portions 314, 334, and the surfaces of the connection bodies 312, 332 on one end side, are disposed opposite the inner circumferential portions 802, 802. Note that the connection bodies 312, 332 may be joined to the elastic support portions 81, 82 joined to the support and fastening portions 314, 334 at the peripheral portions of the other end of the connection bodies 312, 332 around the support and fastening portions 314, 334. For example, the connection bodies 312, 332 and the elastic support portions 81, 82 may be joined using an adhesive, or by welding, etc. Alternatively, the connection bodies 312, 332 may be joined to the elastic support portions 81, 82 by sandwiching the elastic support portions 81, 82 between them using other members such as rivets. This allows the connection bodies 312, 332 and the inner circumferential portions 802, 802 to be reliably joined to each other, and the elastic support portions 81, 82 and the movable body 20 to be joined more reliably.

[0063] Furthermore, the elastic support parts 81, 82 and the support fixing parts 314, 334 may be connected by caulking or by a combination of welding, bonding and caulking. The connecting portions 31 and 33 are formed of, for example, a sintered copper material. The connecting portions 31 and 33 may be formed of a metal that functions as a weight for the movable body 20.

[0064] The connecting portions 31 and 33 are arranged in a position on the movable body 20 that is off the magnetic circuit including the magnet 21 and the first and second yokes 23 and 25. This does not restrict the arrangement space for the pair of coils 61 and 62, meaning that the distance between the magnetic circuit on the movable body side (the magnet 21, the first and second yokes 23 and 25) and the pair of coils 61 and 62 is not increased, and the efficiency of electromagnetic conversion is not reduced. This allows the weight of the movable body 20 to be increased in an appropriate manner, achieving high vibration output.

[0065] Furthermore, if the connecting portions 31 and 33 are made to function as weights, the vibration output of the vibration actuator 1 can be adjusted by adjusting the mass together with the weight portions 27 and 29.

[0066] <Fixed body 40> 3, fixed body 40 has a pair of coils 61, 62, and accommodates movable body 20 having magnet 21 radially inside pair of coils 61, 62. Fixed body 40 supports movable body 20 via elastic support parts 81, 82 so as to be movable in the axial direction of movable body 20 (which is the vibration direction and also the coil axial direction).

[0067] FIG. 9 is a diagram showing the outer surface of the coil assembly in the drive unit with the outer yoke removed from the coil assembly, and FIG. 10 is a diagram showing the coil assembly with the coil removed from the coil holding portion.

[0068] 3 to 6, 9, and 10, fixed body 40 includes case 10, a coil (a pair of coils 61, 62), a coil holding portion 42 that holds coils 61, 62, and an outer yoke 50. This coil assembly, together with movable body 20 and elastic support portions 81, 82, constitutes drive unit 15.

[0069] Fixed body 40 may not include case 10 as long as it is configured to hold pair of coils 61 and 62 and movably support movable body 20 via elastic support portions 81 and 82.

[0070] The coil holding portion 42 is a cylindrical body made of a resin such as phenolic resin, polybutylene terephthalate (PBT), etc. In this embodiment, the coil holding portion 42 is made of a material containing phenolic resin, such as highly flame-retardant bakelite.

[0071] Furthermore, by constructing the coil holding portion 42 from a material containing phenolic resin, flame retardancy is enhanced, and safety during operation can be improved even if heat is generated by Joule heat when a current flows through the holding coil (pair of coils 61, 62).In addition, improved dimensional accuracy and positional accuracy of the coils (pair of coils 61, 62) can reduce variations in vibration characteristics.

[0072] As shown in Figures 9 and 10, the coil holding portion 42 has a cylindrical main body portion 422, flange portions 426 to 428 protruding radially from the outer peripheral surface of the cylindrical main body portion 422, a routing portion 41 having a terminal pull-out portion 46 and a connecting groove portion 47, and engaging protrusions 44 and 45.

[0073] The coil holding portion 42 is formed into a coil bobbin shape by a cylindrical main body portion 422 and flange portions 426 to 428. The coil holding portion 42 has coil attachment portions 42b and 42c around which a coil (a pair of coils 61, 62) is wound between the flange portions 426 to 428.

[0074] Cylindrical main body 422 is located radially inside pair of coils 61, 62, and has inner circumferential surface 42a that faces the outer circumferential surface of movable body 20 at a predetermined interval. This predetermined interval is a distance that allows movable body 20 to move without coming into contact with inner circumferential surface 42a when moving in the vibration direction.

[0075] Cylindrical main body 422 is positioned between magnet 21 and the pair of coils 61, 62, thereby preventing contact between magnet 21 and the pair of coils 61, 62. Cylindrical main body 422 guides movable body 20 so that it can reciprocate along inner circumferential surface 42a.

[0076] That is, the cylindrical main body 422 functions as a protective wall that protects the pair of coils 61, 62 from collision with the movable body 20 when the movable body 20 is driven. The thickness of the cylindrical main body 422 is thick enough to have no effect on the pair of coils 61, 62 on the outer periphery even if the moving movable body 20 comes into contact with it.

[0077] The coil attachment portions 42 b and 42 c are provided in a concave shape on the outer circumferential surface of the cylindrical main body portion 422 .

[0078] Specifically, the coil mounting portions 42b, 42c (see Figure 10) are formed by the outer peripheral surface of the cylindrical main body portion 422 and the flange portions 426 to 428 so as to open radially outward from the outer peripheral surface of the cylindrical main body portion 422 to the outer peripheral side.

[0079] Coil attachment portions 42b, 42c are provided so as to be separated by flange portions 426 to 428. A pair of coils 61, 62 are wound around coil attachment portions 42b, 42c. The pair of coils 61, 62 are wound between flange portions (also referred to as "end flange portions") 427, 428 so as to sandwich central flange portion (hereinafter also referred to as "central flange portion") 426 in the vibration direction.

[0080] The coils 61, 62 in the coil mounting portions 42b, 42c are arranged in a line in the coil axis direction so as to surround the outer surfaces of the first yoke 23 and second yoke 25 of the movable body 20 (the outer surfaces of the magnet 21 and the first yoke 23 and second yoke 25).

[0081] Central flange portion 426 has an annular outer periphery and is provided in an annular shape protruding radially outward from the outer periphery of cylindrical main body portion 422. Note that a routing portion 41 for routing the winding is provided on a part of the outer periphery of central flange portion 426.

[0082] The diameter of the central flange portion 426 excluding the terminal lead-out portion 46, i.e., the diameter of the outer peripheral portion 426a, is shorter than the maximum diameter of the other flange portions (end flange portions 427, 428). As a result, a recessed portion 420 is formed on the outer peripheral surface of the coil holding portion 42, located in the central portion in the vibration direction, and at the open ends of the coil mounting portions 42b, 42c (see FIGS. 9 and 10).

[0083] As a result, the outer yoke 50 fits into the recessed portion 420, and the outer yoke 50 covers the coil mounting portions 42b, 42c on which the coils 61, 62 are arranged, with its outer surface positioned flush with the outer surfaces of the end flange portions 427, 428.

[0084] In the routing section 41, the terminal draw-out section 46 processes the ends (windings 63) of the coils 61, 62 so that they can be connected to an external device, and the communication groove section 47 guides the coil windings 64. As a result, the coil windings (for example, windings 64) are routed so that the coil holding section 42 can appropriately hold the coils 61, 62.

[0085] 9 and 10, the terminal draw-out portion 46 has a terminal entangling portion 43. The terminal entangling portion 43 entangles the winding 63 at the end of the winding that connects the pair of coils 61, 62, and functions as a connector connecting portion that connects to an external device. The terminal entangling portion 43 connects the pair of coils 61, 62 to an external device (for example, a power supply unit such as a drive control unit), enabling power to be supplied from the external device to the pair of coils 61, 62.

[0086] The terminal tying portion 43 is a conductive member that protrudes from the coil holding portion 42, specifically, from the outer periphery of the cylindrical main body portion 422. The terminal tying portion 43 has a rod-shaped body for tying the coil windings.

[0087] Terminal binding portion 43 is provided by press-fitting its base end into terminal pull-out portion 46 that protrudes from the outer periphery of coil holding portion 42, specifically, the outer periphery of central flange portion 426 of coil holding portion 42. Winding 63 at the end of the winding that constitutes coils 61, 62 is bound and connected to terminal binding portion 43, and this connection is securely joined with ferrules 432 formed by solder.

[0088] Terminal lead-out portion 46 protrudes from the outer peripheral surface of central flange portion 426 and is provided at central flange portion 426 with a predetermined radial length, a thickness in the vibration direction, and a width along the circumferential direction, thereby ensuring a press-fit margin for terminal binding portion 43. The width of terminal lead-out portion 46 is parallel to a tangent to the outer periphery of central flange portion 426, and here terminal lead-out portion 46 is formed in the shape of a rectangular parallelepiped, with terminal binding portion 43, i.e., both ends of coils 61 and 62, protruding from its tip surface.

[0089] The terminal pull-out portion 46 has a press-fit margin for the terminal tying portion 43, so that the terminal tying portion 43 can be firmly held, and the terminal tying portion 43 can be stably fixed when assembled to the coil holding portion 42.

[0090] Terminal lead-out portion 46 leads the ends of the windings of the coils (pair of coils 61, 62) out of vibration actuator 1 via terminal binding portion 43 and connects them to a power supply. Terminal lead-out portion 46 passes through outer yoke 50, exposing terminal binding portion 43 to the outside of outer yoke 50 and ultimately to the outside of case 10.

[0091] The terminal binding portion 43 is provided on the terminal pull-out portion 46, so that even if the outer yoke 50 comes into contact with the terminal pull-out portion 46 and applies a load to the terminal pull-out portion 46 when the terminal pull-out portion 46 is inserted into the outer yoke 50, the load can be received by the terminal pull-out portion 46.

[0092] This prevents the load applied when the outer yoke 50 is attached from being applied to the terminal binding portion 43, preventing deformation of the terminal binding portion 43 due to the applied load, and enabling the vibration actuator to be manufactured stably. Note that adhesive portions may be provided on the outer peripheral surfaces of the flange portions 426 to 428, which have the same outer diameter, and the outer yoke 50 may be fixed to each of the flange portions 426 to 428 via the adhesive portions. This configuration allows for more stable vibration characteristics to be achieved.

[0093] A coil winding 64 that connects the coils (a pair of coils 61, 62) is inserted into the communication groove portion 47. In the communication groove portion 47 of the present embodiment, the winding directions of the coil windings that form the coils 61 and 62 are reversed so that they are in opposite directions above and below the communication groove portion 47.

[0094] The communication groove 47 is formed to open radially outward at the outer periphery of the central flange 426 and to penetrate along the vibration direction. Specifically, the communication groove 47 has a bottom wall 47a forming a groove-shaped bottom, and a side wall (one side wall) 47b of the bottom wall 47a that is farther from the terminal binding portion 43.

[0095] Even when the central flange portion 426 is covered by the outer yoke 50, the communication groove portion 47 communicates the coil mounting portions 42b, 42c in the vibration direction on the radially inner side of the outer yoke 50. The communication groove portion 47 is disposed close to or adjacent to the terminal lead-out portion 46.

[0096] As shown in Fig. 9, the communication groove 47 is a notch-shaped portion having a sloping bottom surface between the parallel wall surfaces of the side wall of the terminal pull-out portion 46 and the far side wall portion 47b. The notch-shaped portion functions to lock the winding so that it does not come off when, after winding and placing one of the coils 61 and 62, the winding direction is reversed and the other coil is wound and placed. The communication groove 47 of this embodiment is formed in a U-shape in plan view, with the bottom wall portion 47a as the bottom surface and both side wall portions standing on both ends spaced apart in the circumferential direction.

[0097] Therefore, when the pair of coils 61, 62 are arranged by winding the coil winding 64 around the coil mounting portions 42b, 42c in upside-down directions, the coil winding 64 is reliably engaged with and retained in the connecting groove portion 47 so as not to come off the connecting groove portion 47. As a result, the coil winding 64 is suitably guided from one of the coil mounting portions 42b, 42c to the other by the connecting groove portion 47. This makes it easy to assemble the pair of coils 61, 62 to the coil holding portion 42 using a single coil winding.

[0098] In addition, the routing portion 41 has a coil guide portion 412 in the central flange portion 426 that guides the coil winding 63 from the terminal binding portion 43 to the first turn position (e.g., a corner) in the coil winding portion (one of the coil mounting portions 42b, 42c) of the coil holding portion 42 (see Figure 10).

[0099] Coil guide portion 412 is provided on at least one of the upper and lower surfaces (surfaces separated in the vibration direction) of central flange portion 426. In the present embodiment, coil guide portion 412 is formed as a step on the upper surface portion of connecting groove portion 47 adjacent to terminal lead-out portion 46 on one side in the circumferential direction in central flange portion 426, and on the lower surface portion of terminal lead-out portion 46.

[0100] The coil guide portion 412 is an inclined portion formed by steps on the upper and lower surfaces (surfaces in the vibration direction) of the central flange portion 426, and guides the coil winding from the terminal binding portion 43 so that it can be pulled in to the bottom side of the coil mounting portions 42b and 42c, that is, the outer peripheral surface side of the cylindrical main body portion 422.

[0101] For example, in Figure 10, after the coil windings are entangled with one of the terminal entanglement portions 43 (for example, the terminal entanglement portion 43 on the right side in the figure), the coil is guided along the coil guide portion 412 on the coil mounting portion 42c side, and the coil 62 is wound and positioned around the coil mounting portion 42c.

[0102] This stabilizes the position of the first turn of the wire compared to when the wire is drawn directly from the terminal binding portion 43 to the coil mounting portion 42c, allowing for more suitable placement of the coil 62. The end portion of the wire of the coil 62 is then guided through the connecting groove 47 to the coil mounting portion 42b, and the coil winding is wound around the coil mounting portion 42b in the opposite direction to that of the coil 62, thereby forming and placing the coil 61.

[0103] In this way, when winding the coil winding extending from the terminal binding portion 43 around the coil mounting portions 42b and 42c, the coil guide portion 412 can stabilize the position of the first turn of the winding at the coil mounting portions 42b and 42c, thereby ensuring that one turn of the winding can be made.

[0104] This allows the vibration actuator 1 to be assembled in a single process, including winding the winding to the terminal winding portion 43, forming the upper and lower coils 61 and 62, and finally winding the winding to the terminal winding portion 43. This makes it possible to easily automate the coil formation process and the like, and realize a vibration actuator with an efficient assembly structure.

[0105] End flanges 427 and 428 are provided at both ends of cylindrical main body 422 that are spaced apart in the axial direction, and constitute the upper and lower ends of coil holding portion 42 .

[0106] End flanges 427, 428 (collectively referred to as "end flanges") are provided so as to protrude radially from the outer periphery of cylindrical main body 422 to both ends in the vibration direction. The outer peripheries of end flanges 427, 428 each have a portion with the same diameter as outer periphery 426a of central flange 426. These same-diameter portions form recessed portion 420, and this same-diameter portion abuts against the inner circumferential surface of outer yoke 50.

[0107] By placing outer yoke 50 in this recessed portion 420, outer yoke 50 is positioned at a position surrounding a pair of coils 61, 62. Furthermore, outer yoke 50 is stably fixed to coil holding portion 42 by abutting outer periphery 426a against the same diameter portions of end flange portions 427, 428. As a result, even if the height dimension (length in the vibration direction) of outer yoke 50 increases, it can be stably fixed using an attachment method that corresponds to that increase.

[0108] End flange portions 427, 428 are formed in a cylindrical shape that opens in a direction (vertical direction in this embodiment) away from central flange portion 426. Elastic support portions 81, 82 are fixed to the open end portions of end flange portions 427, 428, i.e., the upper and lower end portions.

[0109] The engaging protrusions 44, 45 are protrusions protruding in the vibration direction (vertical direction) at the upper and lower ends of the coil holding portion 42, i.e., at the upper and lower annular opening end faces (also referred to as the "upper end face" and the "lower end face") 427a, 428a of the end flange portions 427, 428, respectively.

[0110] 3 and 4, the engaging protrusions 44, 45 engage with the engaging recess 127 of the lid portion 12 of the case 10 and the engaging recess 117 (see FIG. 12) of the case body 11. By engaging with the engaging recesses 127, 117, the engaging protrusions 44, 45 position the coil holding portion 42, the lid portion 12, and the case body 11 in the radial direction and the vibration direction, and also position the elastic support portions 81, 82 that are sandwiched between them in the radial direction.

[0111] The engaging protrusions 44, 45 are arranged to face the top surface 122 of the lid portion 12 and the bottom surface 114 of the case body 11, respectively, and the end flange portions 427, 428 receive the top surface 122 and the bottom surface 114 while sandwiching the elastic support portions 81, 82, respectively.

[0112] The elastic support parts 81, 82 are positioned relative to the coil holding part 42 by fitting the engaging protrusions 44, 45 into the positioning groove part 808. This allows the positions of the elastic support parts 81, 82 to be set uniformly for each individual drive unit 15, enabling stable positioning of the elastic support parts 81, 82 relative to the coil holding part 42. This restricts movement of the elastic support parts 81, 82 in the rotational direction, suppresses variation in the elastic support parts 81, 82 as a product, and achieves stable characteristics.

[0113] A plurality of engaging protrusions 44, 45 are provided at equal intervals around the axis of the coil holding portion 42.

[0114] Furthermore, the multiple engaging protrusions 44, 45 engage with the positioning grooves 808 of the elastic support parts 81, 82. This reduces the likelihood of the elastic support parts 81, 82 getting caught or frictioning when the movable body 20 is inserted into the coil holding part 42, allowing for easy assembly and positioning of the movable body 20 and the coil holding part 42.

[0115] In addition, the coil holding portion 42 is accommodated in a state where the engaging protrusions 44, 45 at the upper and lower ends engage with the engaging recesses 127, 117 of the case 10, facing the edge of the lid portion 12 and the edge of the bottom portion 114, and is fixed within the case.

[0116] <Coils 61 and 62> In the vibration actuator 1, the pair of coils 61, 62, together with the magnet 21, the first yoke 23 and the second yoke 25, form a magnetic circuit used to generate a driving force, with the axial direction of the pair of coils 61, 62 (the magnetization direction of the magnet 21) being the vibration direction.

[0117] The pair of coils 61, 62 are energized when driven (when vibrating) and constitute a voice coil motor together with the magnet 21. Although a pair of coils 61, 62 is used in this embodiment, one or three or more coils may be used as long as they form a magnetic circuit that is driven in the same way, but it is desirable to have an even number of coils so that they are symmetrical in the vibration direction.

[0118] The pair of coils 61, 62 are arranged in positions symmetrical in the vibration direction with respect to the magnet 21 as the center with respect to the movable body 20 which has the magnet 21, the first yoke 23, the second yoke 25, etc. It is preferable that the center position of the length of the coils in the vibration direction, that is, the center position of the length between the upper end of coil 61 and the lower end of coil 62, be the same position (including approximately the same position) as the center position of the length of the movable body 20 (particularly the magnet 21) in the vibration direction.

[0119] In this embodiment, the pair of coils 61 and 62 are formed by winding a single coil in opposite directions, and when energized, current flows in opposite directions through the coils 61 and 62, respectively.

[0120] The ends of the pair of coils 61 and 62, that is, the ends of the windings of the coils constituting the pair of coils 61 and 62, are wound and connected to the terminal winding portion 43 of the flange portion 426.

[0121] The coils (pair of coils 61, 62) are connected to a power supply unit (for example, the drive control unit 203 shown in FIGS. 22 and 23) via the terminal binding unit 43. For example, each end of the coils (pair of coils 61, 62) is connected to an AC supply unit via the terminal binding unit 43, and AC power (AC voltage) is supplied from the AC supply unit to the coils (pair of coils 61, 62). This allows the coils (pair of coils 61, 62) to generate thrust between them and the magnet, which allows them to move toward and away from each other in their axial directions.

[0122] 10, the coil (a pair of coils 61, 62) has one end wound around one of the terminal binding sections 43, and the other end of the winding is guided to a position where the first turn is to be formed in the coil mounting section 42c by a step in the coil guide section 412 on the coil mounting section 42c side. At this first turn position, the winding is wound counterclockwise to form the first turn, and then the winding is wound counterclockwise successively to form the coil 62.

[0123] Next, the winding on the other end of coil 62 is guided to coil mounting portion 42b through connecting groove 47 as described above, and the winding direction is reversed within connecting groove 47 to position it at the first winding position of coil mounting portion 42b. Thereafter, the winding is reversed relative to coil mounting portion 42c, in this case clockwise, to form coil 61 within coil mounting portion 42b. While in this embodiment, the coil (pair of coils 61, 62) is formed from a single winding, this is not limiting and separate coils (pair of coils 61, 62) may also be used. In this configuration, if the separate coils are wound in the same direction, currents of different directions are supplied to each coil during operation.

[0124] It is preferable that the coil axes of the pair of coils 61 and 62 are arranged coaxially with the axis of the coil holding portion 42 or the axis of the magnet 21 .

[0125] In the vibration actuator 1, the pair of coils 61, 62 are formed into a cylindrical shape by winding a coil wire around the coil attachment portions 42b, 42c from the outside of the coil holding portion 42. This allows the coils 61, 62 to be assembled without using a self-bonding wire, thereby realizing a reduction in the cost of the coils (the pair of coils 61, 62) themselves, and ultimately a reduction in the cost of the entire vibration actuator.

[0126] <Outer yoke 50> FIG. 11 is a bottom perspective view of the outer yoke. As shown in FIGS. 3 to 6, 9 and 11, the outer yoke 50 is a cylindrical magnetic body that surrounds the outer peripheral surface of the coil holding portion 42 and is positioned to cover the pair of coils 61, 62 from the radial outside.

[0127] As described above, the outer yoke 50 forms a magnetic circuit on the fixed body side together with the pair of coils 61, 62, and also forms a magnetic circuit on the movable body side, that is, a magnetic circuit together with the magnet 21, the first yoke 23, and the second yoke 25. The outer yoke 50 prevents leakage of magnetic flux from the magnetic circuit to the outside of the vibration actuator 1.

[0128] Outer yoke 50 can increase the thrust constant in the magnetic circuit and improve the electromagnetic conversion efficiency. Outer yoke 50 utilizes the magnetic attractive force of magnet 21 to function as a magnetic spring together with magnet 21, reducing stress when elastic support members 81 and 82 are used as mechanical springs, thereby improving the durability of elastic support members 81 and 82.

[0129] In the vibration actuator 1, when the coils 61, 62 are energized via the terminal binding portion 43, the coils 61, 62 and the magnet 21 cooperate to move the movable body 20 back and forth in the vibration direction within the case 10.

[0130] The outer yoke 50 is positioned so that the center of the length of the outer yoke 50 in the vibration direction is at the same height as the center of the vibration direction of the magnet 21 placed inside. The shielding effect of this outer yoke 50 can reduce magnetic flux leakage to the outside of the vibration actuator.

[0131] When the movable body 20 moves, the two ends of the outer yoke 50 that are separated in the vibration direction are positioned lower than the two ends of the movable body 20 in the vibration direction. In other words, the outer yoke 50 is configured to have a length that does not cover the two ends of the movable range of the laminated body in which the magnet 21, the first yoke 23, and the second yoke 25 are laminated in the vibration direction.

[0132] Outer yoke 50 has yoke body 51 and a plurality of openings (first opening 53, second opening 55) provided at the same position in the vibration direction of yoke body 51 and dispersed in the circumferential direction.

[0133] The yoke body 51 is formed in a cylindrical shape and is made of, for example, SECC (electro-galvanized steel sheet), which has excellent weldability and corrosion resistance.

[0134] In this embodiment, yoke body 51 is flexible and has a slit parallel to the axial direction in part of its peripheral wall. Yoke body 51 is formed into a C-shaped cylinder in a planar cross section. When yoke body 51 is attached to the outer periphery of coil holding portion 42, ends 52 constituting the slit are widened to position coil holding portion 42 inside yoke body 51. Next, yoke body 51 is restored to its original shape and fitted into recessed portion 420 on the outer periphery of coil holding portion 42, thereby fitting yoke body 51 onto coil holding portion 42.

[0135] The plurality of openings 53, 55 are provided in the yoke body 51 so that the opposing edges of the openings 53, 55 in the vibration direction are positioned at the same positions. The openings 53, 55 are formed in the yoke body 51 at positions facing each other with the axis of the outer yoke 50 at the center, for example.

[0136] The plurality of openings 53, 55 are all provided in the center in the vibration direction of the yoke body 51. The plurality of openings 53, 55 may be provided in the yoke body 51 at equal intervals in the circumferential direction.

[0137] In this embodiment, the multiple openings 53, 55 are formed in the yoke body 51 in a rectangular shape, separated in the circumferential direction by parallel sides spaced apart in the circumferential direction, and separated in the vibration direction by upper and lower sides that are symmetrically formed and spaced apart in the vibration direction.

[0138] The multiple openings 53, 55 include a first opening 53 for passing wiring connecting an external device to coils 61, 62, and a second opening 55 provided at a predetermined position based on the position of first opening 53. Opening 53 is provided so as to extend circumferentially in the center of the slit portion of yoke body 51. The upper and lower side portions that separate opening 53 are formed by end portions 52 of yoke body 51 that extend circumferentially and face each other in the circumferential direction.

[0139] Terminal lead-out portion 46 is inserted into opening 53. As a result, terminal binding portion (wiring) 43 connected to coils 61 and 62 passes through opening 53, and terminal binding portion (wiring) 43 is disposed in an exposed state protruding outside outer yoke 50 so as to be connectable to an external device.

[0140] Furthermore, the opening 53 functions as a stopper for preventing the outer yoke 50 from rotating in the circumferential direction relative to the coil holding portion 42 by fitting into the terminal lead-out portion 46 .

[0141] Opening 53 has cutouts 533 formed on diagonally arranged edges of the left and right sides that separate opening 53, so as to widen opening 53. That is, opening 53 has a cutout shape such that the positions of the edges extending along the vibration direction are shifted in the circumferential direction.

[0142] The end of the winding connected to the terminal binding portion 43 is wired inside the cutout portion 533. When the outer yoke 50 is fitted into the recessed portion 420 of the coil holding portion 42, the terminal lead-out portion 46 is positioned inside the opening 53 so as to close the opening 53. At this time, the winding connecting the terminal binding portion 43 of the terminal lead-out portion 46 and the coils 61, 62 inside the outer yoke 50 is wired without being obstructed inside the cutout portion 533, which is cut out so as to be offset in the circumferential direction. Therefore, the outer yoke 50 can be suitably attached to the coil holding portion 42 without the coil winding getting in the way.

[0143] In outer yoke 50, the left and right side portions that circumferentially divide opening 53 may be formed to sandwich terminal lead portion 46. In this case, the protruding side portions adjacent to cutout portion 533 can press terminal lead portion 46 from both sides in the circumferential direction to hold terminal lead portion 46. This allows outer yoke 50 to be securely attached to coil holding portion 42 with terminal lead portion 46 sandwiched in the circumferential direction.

[0144] Furthermore, opening 53 is divided into two regions spaced apart in the vibration direction by terminal pull-out portion 46, and band-shaped open regions extending in the circumferential direction and communicating with notch portion 533 are formed on both sides (up and down) of terminal pull-out portion 46 in the vibration direction. Windings connecting terminal binding portion 43 and coil mounting portions 42b, 42c are suitably arranged in the band-shaped regions including cut-out portion 533.

[0145] Opening (second opening) 55 is provided at a position facing opening 53 with respect to the radial center. Opening 55 is formed, for example, in yoke body 51 at a position facing opening 53. Opening 55 has substantially the same shape as opening 53, and is formed in a rectangular shape extending in the circumferential direction and bounded by top, bottom, left, and right sides.

[0146] The widths in the vibration direction of the upper and lower side portions 55a, 55b that separate the opening 55 are formed to be approximately the same as the widths in the vibration direction of the upper and lower side portions of the opening 53.

[0147] Openings 53 and 55 form a magnetic path in the magnetic circuit that is symmetrical about the axis, ensuring a balance of the generated magnetism. That is, openings 53 and 55 allow movable body 20 and fixed body 40 to attract each other equally in the vibration direction and in a direction perpendicular to the vibration direction (radial direction), i.e., in the up / down and left / right directions. As a result, movable body 20 vibrates relative to the fixed body while being attracted to each other equally in the radial direction.

[0148] In this way, openings 53, 55 are each formed in a shape that is longer in the circumferential direction than in the vibration direction (vertical direction) at the center in the vibration direction of the main body of outer yoke 50. Because the upper and lower sides of outer yoke 50 are located above and below openings 53, 55, an imbalance in magnetic attraction force in the magnetic circuit and leakage magnetic flux can be kept to a minimum.

[0149] In this embodiment, each of the upper and lower side portions that separate opening 53 is divided in the circumferential direction by a slit sandwiched between end portions 52, which differs from a configuration in which the upper and lower side portions have no slits. However, because the division of opening 53 into the upper and lower side portions results in a short distance between end portions 52 that face each other in the circumferential direction via the cutout, it has the same function as upper and lower side portions without slits and provides the same effect in terms of the magnetic circuit.

[0150] In this embodiment, openings 53 and 55 are configured to be provided at two locations facing each other in the center of the outer yoke 50 in the vertical direction (vibration direction), but two or more openings may be provided as long as they are spaced apart at equal intervals around the axis of the outer yoke 50.

[0151] <Elastic support portions 81, 82> As shown in FIGS. 3 to 9, the elastic support portions 81 and 82 support the movable body 20 so that the movable body 20 can move back and forth relative to the fixed body 40 in the vibration direction.

[0152] The elastic support parts 81 and 82 sandwich the movable body 20 in the vibration direction of the movable body 20, and are installed across both the movable body 20 and the fixed body 40 so as to intersect with the vibration direction.

[0153] In this embodiment, as shown in Figures 3 to 9, the elastic support parts 81 and 82 are attached parallel to each other across both ends (upper and lower ends) of the coil holding part 42 that are spaced apart in the vibration direction and both ends of the movable body.

[0154] The elastic support portions 81 and 82 are formed in a disk shape, and have a shape in which an annular inner peripheral portion 802, which is the inner spring end, and an annular outer peripheral portion 806, which is the outer spring end, are joined by a deformation arm 804 that is an arc-shaped in a planar view and elastically deforms.

[0155] The deforming arms 804 are arranged in a spiral shape connecting the inner peripheral portion 802 and the outer peripheral portion 806, and deformation of the deforming arms 804 causes the inner peripheral portion 802 and the outer peripheral portion 806 to be displaced relative to each other in the axial direction.

[0156] The elastic support portions 81 and 82 support the movable body 20 so as to be movable in the axial direction (vibration direction) without contacting the fixed body 40.

[0157] The elastic support members 81 and 82 are each a plurality of flat plate-shaped leaf springs. The movable body 20 may have three or more leaf springs as the plurality of elastic support members 81 and 82. These plurality of leaf springs are attached along a direction perpendicular to the vibration direction.

[0158] Furthermore, when movable body 20 is driven (vibrated) or receives an external impact, elastic support members 81, 82 come into contact with inner circumferential surface 42a of cylindrical main body 422 of movable body 20, but do not come into contact with pair of coils 61, 62, and therefore will not be damaged. Furthermore, elastic support members 81, 82 may be configured with any material as long as they elastically support movable body 20. In this embodiment, elastic support members 81, 82 are the same members having the same configuration.

[0159] The inner circumferential portion 802 has a connection hole 802a disposed at the center of the elastic support portions 81 and 82. Both ends of the movable body 20 that are separated in the vibration direction (the support fixing portions 314 and 334 of the connection portions 31 and 33) are fitted into and connected to this connection hole 802a. The inner circumferential portion 802 is fitted so as to sandwich the support fixing portions 314 and 334 in a direction perpendicular to the direction in which they protrude.

[0160] On the other hand, the outer peripheral portion 806 is attached to the upper and lower ends of the coil holding portion 42, i.e., the opening end faces 427a, 428a of the end flange portions 427, 428. The outer peripheral portion 806 may be fixed to the opening end faces 427a, 428a of the end flange portions 427, 428 by being adhered to the opening end faces 427a, 428a with an adhesive or the like. Furthermore, the outer peripheral portion 806 may be fixed by being sandwiched between the opening end faces 427a, 428a and the positioning surface portions 128, 118 on the case 10 side, with the engaging protrusions 44, 45 engaged with the positioning groove portion 808 and positioned. In this embodiment, the outer peripheral portion 806 is fixed by being sandwiched between the opening end faces 427a, 428a and the positioning surface portions 128, 118 on the case 10 side.

[0161] The leaf springs serving as elastic support members 81 and 82 may be formed from any elastically deformable material, including stainless steel, phosphor bronze, and the like, by sheet metal processing. In this embodiment, elastic support members 81 and 82 are thin, flat, disk-shaped spiral springs made of phosphor bronze, which has high workability, corrosion resistance, tensile strength, and abrasion resistance. Furthermore, if they are formed from a non-magnetic material such as phosphor bronze, they do not disrupt the flow of magnetic flux in the magnetic circuit. Elastic support members 81 and 82 may be formed from resin, as long as they support movable body 20 so that it can vibrate. Furthermore, because elastic support members 81 and 82 are flat, they can achieve improved positional accuracy, i.e., improved processing accuracy, compared to conical springs.

[0162] In this embodiment, the plurality of elastic support portions 81, 82 are joined to the coil holding portion 42 and the movable body 20 in such a manner that the spiral directions are the same.

[0163] In this manner, in this embodiment, multiple spiral-shaped leaf springs are used as multiple elastic support parts 81, 82 with the same spiral orientation, and are attached to both ends of the movable body 20 that are spaced apart in the vibration direction, thereby elastically supporting the movable body 20 relative to the fixed body 40.

[0164] As a result, when the movement amount of movable body 20 increases, the movable body moves in a translational direction (here, a direction on a plane perpendicular to the vibration direction) while rotating slightly. If the spiral directions of the multiple leaf springs are opposite to each other, the multiple leaf springs will move in the buckling or pulling direction relative to each other, which will hinder smooth movement.

[0165] In this embodiment, the elastic support members 81, 82 are fixed to the movable body 20 so that their spiral directions are the same, and therefore, even if the amount of movement of the movable body 20 increases, they can move smoothly in the vibration direction, i.e., can deform. This results in a larger amplitude, making it possible to increase the vibration output. However, depending on the desired vibration range of the movable body 20, the spiral directions of the multiple elastic support members 81, 82 may be designed to be opposite to each other.

[0166] The plate-like elastic support members 81, 82 are arranged with respect to the movable body 20 such that the inner circumferential portions 802 of the elastic support members 81, 82 overlap the spring fixing portions 313, 333 that constitute the ends of the movable body 20 in the vibration direction. Note that the spring fixing portions 313, 333 may be bonded to the inner circumferential portion 802 by applying an adhesive or the like to them. In this case, the spring fixing portions 313, 333 may be firmly bonded to the inner circumferential portion 802 via adhesive that accumulates in arc-shaped cutouts formed around the periphery of the inner circumferential portion 802.

[0167] Furthermore, the outer peripheral portion 806 of the elastic support portion 81 is positioned and fixed on the annular opening end face 427a of the end flange portion 427 at a location that avoids the engaging protrusion 44. On the other hand, the outer peripheral portion 806 of the elastic support portion 82 is positioned and fixed on the annular opening end face 428a of the end flange portion 428 at a location that avoids the engaging protrusion 45.

[0168] In this way, the elastic support portions 81 and 82 are clamped between the opening end faces 427a and 428a of the upper and lower opening edge portions of the coil holding portion 42 and the lid portion 12 and bottom portion 114 of the case 10, in a state where they are arranged in a direction perpendicular to the vibration direction.

[0169] In addition, the elastic support portions 81, 82 are attached to the coil holding portion 42 and the movable body 20 housed inside the coil holding portion 42 so as to close the upper and lower openings of the coil holding portion 42 around which the pair of coils 61, 62 are wound on the outer periphery.

[0170] The elastic support members 81 and 82 have connection holes 802a in the inner peripheral portion 802 fitted into the support fixing portions 314 and 334 at the upper and lower ends of the movable body 20. Then, the positioning grooves 808 are engaged with the engaging protrusions 44 and 45, and the outer peripheral portion 806 is fixed in contact with the open end faces 427a and 428a of the coil holding portion 42. This results in a drive unit 15 in which the positional relationship between the coils (pair of coils 61 and 62) and the movable body 20 is defined, making it easy to arrange the drive unit 15 within the case 10.

[0171] <Case 10> 12 is a perspective view of the top surface side of the case body 11, and FIG. 13 is a perspective view of the bottom surface side of the lid portion 12. As shown in FIG.

[0172] As shown in FIGS. 1 to 4, 12 and 13, the case 10 accommodates the drive unit 15 by closing an opening 115 of a cylindrical case body 11 with a bottom with a lid 12.

[0173] Case body 11 is formed by closing one opening of cylindrical peripheral wall portion 112 with bottom portion 114. Peripheral wall portion 112 is provided with cutout portion 113 that is cut out on the side of opening 115, which is the other opening.

[0174] The lid 12 and bottom 114 of the case 10 constitute the top surface 122 and bottom surface (bottom 114) of the vibration actuator 1 in this embodiment, and are arranged opposite the movable body 20 of the drive unit 15 at a predetermined distance in the vibration direction of the movable body 20. The lid 12 is provided hanging down from part of the outer periphery of the top surface 122, and has a hanging part 124 that engages with the notch 113 of the case body 11.

[0175] As shown in FIGS. 2 and 3, the bottom portion 114 has an air vent 116 for releasing compressed air generated by the reciprocating vibration of the movable body 20 to the outside.

[0176] The ventilation hole 116 penetrates the outer periphery of the bottom 114. The ventilation hole 116 is formed in the case body 11 at a position on the opposite side of the central axis from the notch 113. In other words, in the vibration actuator 1, the ventilation hole 116 is positioned on the opposite side of the axis from the position where the terminal binding portion 43 protrudes from the outer periphery.

[0177] Furthermore, ventilation hole 116 is provided in a position where movable body 20 will not collide even if a large external load is applied to case 10, such as when the actuator itself is dropped, causing movable body 20 to be displaced and elastic support members 81 and 82 to deform. Furthermore, ventilation hole 116 is provided in a strong corner of case 10 where bottom 114 and peripheral wall 112 are joined. Thus, even with case 10 having ventilation hole 116, deformation of case 10 due to a large load can be prevented.

[0178] The lid 12 and the bottom 114 define the range of movement of the movable body 20 of the drive unit 15. Mortar-shaped (inverted truncated cone) recesses 122b, 114b are provided on the top surface 122 of the lid 12 and the back surface of the bottom 114 of the case body 11, respectively. The inclined peripheral surfaces of the recesses 122b, 114b are formed to conform to the deformed state of the elastic support members 81, 82.

[0179] The recesses 122b, 114b, together with the internal spaces of the end flanges 427, 428 that open in the vibration direction of the accommodated drive unit 15, define the movable space for the movable body 20 and the elastic support members 81, 82. The movable body 20 moves within this movable space, which is a space within a range in which the elastic support members 81, 82 do not undergo plastic deformation. Therefore, even if a force exceeding the movable range is applied to the movable body 20, the elastic support members 81, 82 do not undergo plastic deformation and come into contact with the fixed body 40 (at least one of the lid 12 and the bottom 114), so that the elastic support members 81, 82 are not damaged and reliability can be improved.

[0180] At the surface of bottom 114 of case body 11 and top surface 122 of lid 12, central portions 114a and 122a are respectively formed in a bulging, flat shape.

[0181] 12 has positioning surfaces 118 protruding from the outer periphery and engaging recesses 117 formed between the positioning surfaces 118 at predetermined intervals.

[0182] The back surface of the top surface portion 122 shown in FIG. 13 has positioning surface portions 128 protruding from the outer periphery, and engaging recesses 127 formed between the positioning surface portions 128 at predetermined intervals.

[0183] Additionally, the outer peripheral surface of the top surface portion 122 is provided with fitting protrusions 126 that protrude radially and fit into the opening 115 of the case body 11 .

[0184] When attaching the lid portion 12 to the case body 11, the drive unit 15 is inserted into the case body 11. At this time, the terminal lead portion 46 is inserted into the notch portion 113, and the engaging protrusion 45 is engaged with the engaging recess 117, so that the drive unit 15 is positioned and housed within the case body 11.

[0185] Furthermore, positioning surface 118 holds outer periphery 806 of elastic support member 82 between itself and opening end surface 428a of end flange 428. Next, while fitting hanging portion 124 of lid 12 into notch 113, top surface 122 is inserted into opening 115 to close it. At this time, engaging protrusion 44 engages with engaging recess 127, and positioning surface 128 holds outer periphery 806 of elastic support member 81 between itself and opening end surface 427a of end flange 427. Lid 12 is fixed to case body 11 by abutting fitting protrusion 126 against the inner periphery of opening 115 and sealing the gap between fitting protrusions 126 with an adhesive or the like.

[0186] In this embodiment, terminal lead-out portion 46 of coil holding portion 42 and hanging portion 124 are arranged in notch 113 of case 10, and are closed by terminal lead-out portion 46 and hanging portion 124. As a result, the terminal binding portion 43 is arranged in a state where it protrudes outward from the outer peripheral surface of the case 10, and the vibration actuator 1 can be easily connected to external devices via the terminal binding portion 43.

[0187] <Operation of vibration actuator 1> The operation of the vibration actuator 1 based on the magnetic circuit configuration will be described with reference to FIGS. 14 to 18. FIG. 14 is a diagram schematically illustrating the magnetic circuit configuration of the vibration actuator. FIGS. 15 to 18 are diagrams used to explain the operation of the actuator body, with FIG. 15 illustrating a vibration state in which the movable body is at a first amplitude position on the top surface side, and FIG. 16 illustrating a vibration state in which the movable body is at a second amplitude position on the top surface side. FIG. 17 is a diagram illustrating a vibration state in which the movable body is at a first amplitude position on the bottom surface side, and FIG. 18 is a diagram used to explain the operation of the actuator body, illustrating a vibration state in which the movable body is at a second amplitude position on the bottom surface side. The second amplitude positions in FIGS. 16 and 18 are the maximum amplitude positions of the movable body in the vibration direction.

[0188] The operation of the vibration actuator 1 will be described using as an example a case where the magnet 21 is magnetized so that the front surface 21a on one side of the magnetization direction (the upper side in this embodiment) is the north pole and the back surface 21b on the other side of the magnetization direction (the lower side in this embodiment) is the south pole.

[0189] In vibration actuator 1, movable body 20 is considered to correspond to the mass part in a vibration model of a spring-mass system, so when resonance is sharp (has a steep peak), the steep peak is suppressed by damping the vibration. By damping the vibration, the resonance becomes less steep, and the maximum amplitude value and maximum movement amount of movable body 20 at resonance do not vary, and vibration with an appropriate, stable maximum movement amount is output.

[0190] In the vibration actuator 1, the pair of coils 61, 62 are arranged so that the coil axes are perpendicular to the magnetic flux from the first yoke 23 and second yoke 25 that sandwich the magnet 21 in the vibration direction.

[0191] Specifically, a magnetic flux flow mf is formed, which is emitted from the surface 21a side of the magnet 21, radiated from the first yoke 23 toward the coil 61 side, passes through the outer yoke 50, and enters the magnet 21 from the second yoke 25 below the magnet 21 via the coil 62.

[0192] Therefore, when current is applied as shown in FIG. 14, the interaction between the magnetic field of magnet 21 and the current flowing through the coils (a pair of coils 61, 62) generates a Lorentz force in the -f direction in the pair of coils 61, 62 according to Fleming's left-hand rule.

[0193] The Lorentz force in the -f direction is perpendicular to the direction of the magnetic field and the direction of the current flowing through the coils (pair of coils 61, 62). Because the coils (pair of coils 61, 62) are fixed to the fixed body 40 (coil holding portion 42), 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 in the F direction on the movable body 20 having the magnet 21. This causes the movable body 20 having the magnet 21 to move in the F direction, that is, toward the lid 12 (top surface 122 of the lid 12) (see FIGS. 15 and 16).

[0194] Furthermore, when the current flow direction of the pair of coils 61, 62 is switched to the opposite direction and current is passed through the pair of coils 61, 62, a Lorentz force is generated in the opposite f direction (see FIG. 14). 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 movable body 20, and movable body 20 moves in the -F direction, that is, toward bottom 114 of case main body 11 (see FIGS. 17 and 18).

[0195] When vibration actuator 1 is not vibrating and not energized, a magnetic attractive force acts between magnet 21 and outer yoke 50, functioning as a magnetic spring. The magnetic attractive force generated between magnet 21 and outer yoke 50 and the restoring forces of elastic support members 81 and 82 that attempt to return them to their original shapes cause movable body 20 to return to its original position.

[0196] <Effects> In the vibration actuator 1, the movable body 20 has a disk-shaped magnet 21, a pair of annular first yokes 23 and second yokes 25, a pair of weights 27 and 29, and connecting portions 31 and 33. A pair of annular first yokes 23 and second yokes 25, each having yoke openings (openings) 232 and 252 at their centers, and a pair of weights 27 and 29, each having through holes 272 and 292, are stacked on a front surface 21a and a back surface 21b of the magnet 21 in the axial direction. The through holes 272 and 292 are continuous with the yoke openings (openings) 232 and 252, respectively, in the axial direction, and the other ends of the connecting portions 31 and 33, which connect the pair of elastic support portions 81 and 82 at their one ends, are arranged within these continuous yoke openings (openings) 232 and 252 and through holes 272 and 292, respectively.

[0197] As a result, by simply attaching the connecting parts 31 and 33 to the magnet 21 using the opening 232 of the pair of annular first yokes 23, the opening 252 of the second yoke 25, and the through holes 272 and 292 of the pair of weight parts 27 and 29 as positioning references, the movable body 20 can be assembled with high precision, with each part appropriately arranged on the axis.

[0198] In this embodiment, the outer diameters of the first yoke 23 and the second yoke 25 are the same as the outer diameter of the magnet 21.

[0199] Therefore, by stacking the first yoke 23 and the second yoke 25 so that their outer diameters match the outer diameter of the magnet 21, the openings 232 and 252 into which the connecting portions 31 and 33 are inserted can be positioned at the center of the front and back surfaces 21a and 21b of the magnet 21. This makes it easy to position the connecting portions 31 and 33 on the axis of the magnet 21, i.e., on the axis of the movable body 20. In this way, the components constituting the movable body 20 are assembled so that they are always positioned on the central axis of the movable body 20, i.e., the axis in the vibration direction, with the magnet 21 at the center.

[0200] Additionally, non-magnetic weights 27, 29 are laminated on the first yoke 23 and the second yoke 25, extrapolating to the connecting portions 31, 33. These weights 27, 29 are laminated on the magnet 21, the first yoke 23, and the second yoke 25 so that they are positioned so as not to face the outer yoke 50 of the fixed body 40 when the movable body 20 is at the maximum amplitude position in the vibration direction (see FIGS. 16 and 18). This prevents the expansion of the magnetic circuit configuration of the vibration actuator 1, resulting in a compact magnetic circuit with high magnetic efficiency. Furthermore, the non-magnetic weights 27, 29 allow for greater design freedom in obtaining desired vibration characteristics for the movable body 20. Weights 27, 29 with different masses can be easily added, changed, or otherwise adjusted, thereby achieving desired vibration characteristics. According to this embodiment, the movable body 20 can be manufactured with high dimensional accuracy, and as a result, the vibration actuator 1 can be made smaller while generating a suitable vibration output and can be driven.

[0201] FIG. 19 is a diagram showing a schematic diagram of the magnetic balance of the vibration actuator of this embodiment in a non-vibrating state. The vibration actuator 1 comprises a fixed body 40 having a pair of coils 61, 62, and a movable body 20 that is disposed radially inside the pair of coils 61, 62 and has a magnet 21 magnetized in the axial direction of the pair of coils 61, 62. In addition, the vibration actuator 1 comprises flat elastic support members 81, 82 that elastically hold the movable body 20 movably in the vibration direction, which is the coil axial direction.

[0202] The pair of coils 61, 62 are arranged on the outer periphery of the cylindrical main body 422 of the coil holding part 42, and the outer peripheral surface 20a of the movable body 20 is arranged on the inner periphery of the cylindrical main body 422 with a predetermined gap between them. The outer peripheral surfaces of the pair of coils 61, 62 are surrounded by the outer yoke 50. The elastic support parts 81, 82 support the movable body 20 so that it does not come into contact with the cylindrical main body 422. The outer yoke 50 forms a magnetic path together with the magnet 21, the first yoke 23, the second yoke 25, and the coils 61, 62.

[0203] Here, the outer yoke 50 has a plurality of openings 53, 55 that are distributed in the circumferential direction and provided at the same position in the vibration direction. The openings 53, 54 are formed so as to balance the magnetic path formed by the magnet 21 and the coils 61, 62 in the circumferential direction.

[0204] 19, movable body 20 having magnet 21 is attracted equally to fixed body 40 having outer yoke 50 with multiple openings 53, 55 on the left and right sides due to the generation of magnetic attractive force J1. In other words, movable body 20 is positioned in a balanced state with respect to fixed body 40 by magnet 21 and outer yoke 50 functioning as a magnetic spring.

[0205] When movable body 20 moves in one direction of the vibration directions (direction F) within the height (range of length in the vibration direction) of outer yoke 50, movable body 20 is attracted equally to the left and right on the upper side due to the left and right magnetic attractive forces J1 on the upper side of movable body 20, as shown in Fig. 15. In this way, when movable body 20 is in a vibration state in the height range up to the top end of outer yoke 50, where it is at a first amplitude position on the top surface side, movable body 20 moves straight in one direction of the vibration directions, here direction F.

[0206] Next, the movable body 20 moves further in one direction (direction F) and protrudes from the outer yoke 50, that is, one end of the movable body 20 moves to a position protruding from the outer yoke 50, as shown in Figure 16.

[0207] If this state is taken as a vibration state in which movable body 20 is at the second amplitude position on the top surface side, i.e., the maximum amplitude position on the top surface side, no magnetic attractive force is generated at either the left or right end of the top or bottom of movable body 20. As a result, in this vibration state in which movable body 20 is at the second amplitude position on the top surface side, movable body 20 and fixed body 40 do not attract each other, and magnetic balance between the left and right sides of movable body 20 is ensured. In this state, movable body 20 moves straight in the vibration direction.

[0208] On the other hand, when the current flow direction of coils 61, 62 is reversed, movable body 20 moves in the other vibration direction (-F direction) within the height of outer yoke 50 (the range of the length in the vibration direction). In this case, as shown in Fig. 17, movable body 20 is attracted equally to the left and right on the underside due to the left and right magnetic attractive forces J1 on the lower side of movable body 20. Thus, in a vibration state in which movable body 20 is at the first amplitude position on the bottom side, which is a vibration state within the vibration range up to the lower end of outer yoke 50, movable body 20 moves straight in the other vibration direction, here the -F direction.

[0209] Next, movable body 20 moves further in the other direction (-F direction) and projects from outer yoke 50, i.e., as shown in FIG. 18, the other end of movable body 20 projects from outer yoke 50. If this state is defined as a vibration state in which movable body 20 is at the second amplitude position on the bottom side, i.e., the maximum amplitude position on the bottom side, no magnetic attractive force is generated at the left and right ends of movable body 20 on the top and bottom sides. As a result, when movable body 20 is at the second amplitude position on the bottom side, movable body 20 and fixed body 40 do not attract each other, and magnetic balance between the left and right sides of movable body 20 is ensured. In this state, movable body 20 vibrates in a straight line in the vibration direction.

[0210] In this way, the vibration actuator 1 vibrates favorably while maintaining magnetic balance regardless of the position of the movable body 20 displaced by vibration, i.e., the vibration state at the first and second amplitude positions on the top surface side and the vibration state at the first and second amplitude positions on the bottom surface side. The magnetic balance is achieved by the outer yoke 50 having multiple openings 53, 55 that are distributed circumferentially and located at the same position in the vibration direction so as to balance the magnetic path formed by the magnet 21 and coils 61, 62 in the circumferential direction.

[0211] Here, the effects of the vibration actuator will be explained more clearly using comparative examples shown in FIGS. 20 and 21. Fig. 20 is a diagram showing the magnetic balance in a non-vibration state of a vibration actuator as a comparative example when there is one opening in the outer yoke. Fig. 21A and Fig. 21B are diagrams used to explain the operation of a vibration actuator as a comparative example, with Fig. 21A showing a vibration state where the movable body is at a first amplitude position on the top surface side, and Fig. 21B showing a vibration state where the movable body is at a second amplitude position on the top surface side.

[0212] The vibration actuator 1A shown in Figure 20 is a comparative vibration actuator that is identical in configuration to the vibration actuator 1 of the embodiment except for the configuration of the outer yoke 50A. That is, in the vibration actuator 1A shown in Figures 20 and 21, the outer yoke 50A has only an opening 53, and unlike the outer yoke 50 of the vibration actuator 1, it does not have any other openings 55.

[0213] Like the vibration actuator 1, when vibration actuator 1A is not driven, magnetic attraction force J2 is generated at the top, bottom, left, and right ends of movable body 20A, as shown in Fig. 20. That is, magnetic attraction force J2 is generated between fixed body 40A and both radial end portions (top, bottom, left, and right ends) of both ends that are separated in the vibration direction.

[0214] As a result, when the vibration actuator 1A is not driven, the movable body 20A is attracted to the fixed body 40A equally on the left and right and up and down, and the movable body 20A is positioned in a state of magnetic balance with respect to the fixed body 40A.

[0215] In the vibration actuator 1A configured in this manner, the magnetic balance changes when the movable body vibrates, as compared to the vibration actuator 1 of this embodiment.

[0216] In vibration actuator 1A, when movable body 20A moves in one direction (direction F), it enters a vibration state in which it moves within the height (range of length in the vibration direction) of outer yoke 50A, as shown in FIG. 21A. In this state, movable body 20A is at a first amplitude position on the top surface side, and magnetic attractive force J2 is generated on the left and right sides of the upper side of movable body 20A, attracting each other equally. Meanwhile, on the lower side of movable body 20A, outer yoke 50A has only opening 53 (the opening on the left side in FIG. 21), so magnetic attractive force J3 is generated on the right side of the lower side of movable body 20A. As shown in FIG. 21A, the magnetic balance differs between the left and right sides of the lower side of movable body 20A. For example, the magnetic attractive force on the side with opening 53 (left side in FIG. 21) relative to the center of movable body 20 is half the magnetic attractive force on the side without opening (right side in FIG. 21A).

[0217] Next, movable body 20A moves further in one direction (direction F) and projects from outer yoke 50A, that is, one end of movable body 20A projects from outer yoke 50A. This state is the second amplitude state on the top surface side, as shown in Fig. 21B, and magnetic attractive force J3 is generated only in the lower right portion of movable body 20A, and movable body 20A is attracted to fixed body 40A only in this portion.

[0218] As a result, a force is generated in movable body 20A that rotates in the direction of arrow U, making it impossible to vibrate movable body 20 straight in the vibration direction.

[0219] In this way, compared to vibration actuator 1A, vibration actuator 1 of this embodiment can generate a suitable vibration output while maintaining magnetic balance and achieving miniaturization regardless of the position of movable body 20 that is displaced by vibration.

[0220] Furthermore, because the vibration actuator 1 is constructed so that the drive unit 15 is housed within the case 10, the outer peripheral surface of the peripheral wall 112 of the case 10 can be made smooth. This allows for a good bond between the outer peripheral surface and the mounting location when attaching a cushioning material such as sponge, such as double-sided tape, when attaching the vibration actuator 1 to an electrical device, and increases the bonding strength.

[0221] Furthermore, since the case is provided with ventilation holes 116, air that has nowhere to go inside the case 10 while the movable body 20 is vibrating can be discharged to the outside, preventing damping of the vibration of the movable body 20. This also prevents dust from entering, making it possible to generate high-output vibrations that are suitable for bodily sensations.

[0222] Since the pair of coils 61, 62 are arranged on the outer peripheral surface of the coil holding portion 42, there is no need to bring the coil wire at the end of the winding outward to connect to an external device during assembly, as compared to when they are arranged on the inner peripheral surface of the coil holding portion 42.

[0223] Furthermore, since the vibration actuator 1 is constructed by placing the drive unit 15 inside the case 10, the elastic support parts 81 and 82, which require high dimensional accuracy, can be fixed by assembling them to the coil holding part 42.

[0224] That is, drive unit 15 is formed by accommodating movable body 20 within coil holding portion 42 and assembling elastic support portions 81 and 82. This allows the arrangement of movable body 20, including the fixation of elastic support portions 81 and 82, to be determined based on coil holding portion 42, thereby improving the accuracy of the direction of vibration generated as a product.

[0225] Specifically, for example, simply by increasing the dimensional accuracy of the coil holding portion 42, which is formed as a single component using resin or the like, it is possible to position the coils 61, 62 attached via the elastic support portions 81, 82 and the magnet 21 of the movable body 20 in an accurate positional relationship. In other words, it is possible to easily manufacture a vibration actuator 1 that vibrates stably.

[0226] The case 10 is formed of a cylindrical, cup-shaped case body 11 with a bottom and a lid 12. This reduces the number of parts and improves assembly ease as well as impact resistance compared to a configuration in which the peripheral wall 112 and the bottom 114 are separate components.

[0227] When the lid 12 is fitted into the opening 115 of the cup-shaped case body 11, the fitting protrusions 126 fit into the opening 115 with arc-shaped slits formed between the fitting protrusions 126 spaced apart in the circumferential direction. The two can be fixed together without providing a protrusion on the outer peripheral surface of the case 10 by welding the arc-shaped slits to fill them or by filling the arc-shaped slits with an adhesive.

[0228] The vibration actuator 1 is driven by an AC wave input from a power supply unit (for example, the drive control unit 203 shown in FIGS. 22 and 23) to a pair of coils 61, 62. In other words, the direction of current flow through the pair of coils 61, 62 switches periodically, and a thrust in the F direction on the top surface 122 side of the lid 12 and a thrust in the -F direction on the bottom surface 114 side act alternately on the movable body 20, as shown in FIG. 14. This causes the movable body 20 to vibrate in the vibration direction.

[0229] The following is a brief explanation of the driving principle of the vibration actuator 1. In the vibration actuator 1 of this embodiment, the mass of the movable body 20 is m [kg], the spring constant of the spring (elastic support portions 81 and 82 which are springs) is K sp In this case, the movable body 20 has a resonance frequency F r Vibrates at [Hz].

[0230]

number

[0231] Since the movable body 20 is considered to constitute a mass part in a vibration model of a spring-mass system, the coil (a pair of coils 61 and 62) is set to have a resonance frequency F r When an AC wave having a frequency equal to the resonant frequency F of the movable body 20 is input, the movable body 20 enters a resonant state. r By inputting an AC wave having a frequency substantially equal to the frequency of the movable body 20, the movable body 20 can be vibrated efficiently.

[0232] Below are shown the equations of motion and circuit equations 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).

[0233]

number

[0234]

number

[0235] That is, the mass m [kg], displacement x(t) [m], and 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 equation (2). In addition, voltage e(t) [V], resistance R [Ω], inductance L [H], back electromotive force constant K e [V / (rad / s)] can be changed as appropriate within a range that satisfies formula (3).

[0236] In this way, in the vibration actuator 1, the mass m of the movable body 20 and the spring constant K of the elastic support members 81 and 82, which are leaf springs, are sp The resonant frequency F is determined by rWhen the coils 61 and 62 are energized with an AC wave corresponding to the above, a large vibration output can be obtained efficiently.

[0237] 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). This allows the vibration actuator 1 to be driven with low power consumption, that is, the movable body 20 to vibrate back and forth in a linear manner with low power consumption. Furthermore, by increasing the damping coefficient D, it is possible to generate vibrations over a wide frequency range.

[0238] According to this embodiment, plate-shaped elastic support members 81, 82 are arranged above and below (in the vibration direction) the movable body 20. This allows the vibration actuator 1 to stably drive the movable body 20 in the vertical direction, while at the same time efficiently distributing the magnetic flux of the pair of coils 61, 62 from the elastic support members 81, 82 above and below the magnet 21. This allows the vibration actuator 1 to achieve high-output vibration.

[0239] Furthermore, the fixed body 40 has a coil holding portion 42 that also functions to protect the pair of coils 61, 62 from the movable body 20. As a result, even if the fixed body 40 receives an impact, it can withstand the impact and prevent damage such as deformation to the elastic support portions 81, 82. Furthermore, since the impact is transmitted to the pair of coils 61, 62 via the resin cylindrical main body portion 422, damage can be suppressed, resulting in a highly reliable vibration actuator 1. In this way, the vibration actuator 1 can be made compact at low cost, is shock resistant, and generates a suitable bodily vibration with high output.

[0240] (electronic equipment) 22 and 23 are diagrams showing examples of mounting forms of the vibration actuator 1. Fig. 22 shows an example in which the vibration actuator 1 is mounted on a game controller GC, and Fig. 23 shows an example in which the vibration actuator 1 is mounted on a mobile terminal M.

[0241] The game controller GC is connected to the game console via wireless communication, for example, and is used by the user by grasping or holding it. The game controller GC here has a rectangular plate shape, and the user grips the left and right sides of the game controller GC with both hands to operate it.

[0242] 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.

[0243] The mobile terminal M is, for example, a mobile communication terminal such as a mobile phone or a smartphone. 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 and a sense of realism).

[0244] 22 and 23, 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.

[0245] In the game controller GC and the mobile terminal M, the vibration actuators 204 to 206 are preferably mounted so that, for example, the main surface of the terminal and a surface perpendicular to the vibration direction of the vibration actuators 204 to 206, in this case the bottom surface of the bottom 114, are parallel.

[0246] The main surface of the terminal is the surface that comes into contact with the user's body surface, and in this embodiment, it means the vibration transmission surface that comes into contact with the user's body surface and transmits vibrations. Note that the main surface of the terminal and the bottom surface of bottom 114 of vibration actuators 204, 205, and 206 may be arranged so as to be perpendicular to each other.

[0247] Specifically, in the game controller GC, vibration actuators 204 and 205 are mounted so that the 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. In addition, in the case of the portable terminal M, vibration actuator 206 is mounted so that the 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.

[0248] 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 unit 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 mobile terminal M, the external communication device is, for example, a base station, and communication is performed in accordance with a mobile communication standard.

[0249] 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).

[0250] 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.

[0251] 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 20 vibrates in a direction perpendicular to the main surfaces of the game controller GC and the mobile terminal M.

[0252] It should be noted that the movable body 20 may be configured to come into contact with the top surface 122 or the bottom surface 114 of the lid 12 via a damper each time it vibrates. In this case, the impact on the top surface 122 or the bottom surface 114 of the lid 12 caused by the vibration of the movable body 20, i.e., the impact on the housing, is transmitted directly to the user as vibration.

[0253] The user can be given a sufficient bodily sensation 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 sensations 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.

[0254] 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.

[0255] Furthermore, the vibration actuator according to the present invention may be mounted on a user contact portion of a portable device other than the game controller GC and the portable terminal M (for example, a portable information terminal such as a tablet PC, a portable game terminal, etc.). That is, the vibration actuator 1 may be mounted on a user contact portion of a handheld electrical device such as a portable terminal or an electric beauty appliance such as a facial massager. The vibration actuator 1 may also be mounted on a user contact portion of a wearable terminal that is worn by the user. In the case of a handheld electrical device such as a game controller GC, the user contact portion is, for example, a handle portion that the user holds during use, and in the case of a wearable electrical device such as a facial massager, the user contact portion is, for example, a pressure portion that applies pressure to the surface of the user's body. [Industrial Applicability]

[0256] The vibration actuator according to the present invention can be manufactured with high dimensional precision while being miniaturized, has the effect of being driven with a suitable vibration output, and is useful as an actuator to be mounted in electric beauty and hairdressing appliances and the like. [Explanation of symbols]

[0257] 1, 204, 205, 206 Vibration Actuator 10 cases 11 Case body 12 Lid 15 Drive unit 20 Movable body 20a Outer surface 21 Magnet 21a surface 21b Back side 23 First York 25 Second York 27, 29 Weight part 31, 33 Connection 40 Fixed body 41 Wiring section 42 Coil holding part 42a Inner surface 42b, 42c Coil mounting part 43 Terminal binding part 44, 45 Engagement protrusion 46 Terminal drawer 47 Connecting groove 50 Outer Yoke 51 Yoke body 52 End 53, 55 Opening 55a Upper edge 55b bottom 61, 62 Coils 63, 64 windings 81, 82 Elastic support part 112 Peripheral wall section 113 Notch 114 Bottom 114a, 122a central part 114b, 122b recesses 115 Opening 116 Ventilation hole 117 Engagement recess 118 Menu 122 Top section 122b Recess 124 Drooping part 126 mating protrusion 127 Engagement recess 128 Positioning surface 201 Communications Department 202 Processing section 203 Drive control unit 232, 252 Yoke opening (opening) 272, 292 through holes 312 Connection body 313, 333 Spring fixing part 314 Support fixing part 332 Connection body 334 Support fixing part 412 Coil guide 420 Concave part 422 Cylindrical main body 426, 427, 428 flange 426a Outer periphery 427a, 428a Open end surface 432 Ferret 533 Notch 802 Inner circumference 802a Connection hole 804 Transforming Arm 806 Outer periphery 808 Positioning groove

Claims

1. a movable body having a disk-shaped magnet without a through hole, a pair of annular yokes each having an opening at the center and a pair of weights each having a through hole continuous with the opening in the axial direction, stacked on the front and back surfaces of the magnet, and one end of a pair of connecting parts connecting a pair of elastic support parts at one end side are arranged in the continuous opening and through hole, facing the front and back surfaces of the magnet; a fixed body having a cylindrical portion that accommodates the movable body, the fixed body being supported by the pair of elastic support portions so that the movable body can vibrate back and forth in the axial direction, and the fixed body having a pair of annular coils that are arranged radially outside the movable body; and the pair of annular yokes, the pair of weight portions, and the pair of connecting portions are provided symmetrically with respect to the magnet on both sides in the vibration direction of the magnet, When the coil is energized, the movable body is vibrated in the axial direction. Vibration actuator.

2. The opening and the through hole, which are continuous with each other, have the same diameter. The vibration actuator according to claim 1 .

3. The outer diameter of the weight portion is smaller than the outer diameter of the yoke.

3. The vibration actuator according to claim 1.

4. The connecting portion has, at the one end side, a support fixing portion connected to the elastic support portion, and at the other end side, a connecting body that is inserted through the through hole and into the opening and joined to the through hole and the opening. The vibration actuator according to claim 1 .

5. the opening is a through hole that penetrates the yoke, the connecting body is joined to the magnet within the opening; 5. The vibration actuator according to claim 4.

6. The support and fixation portion protrudes from the surface of the connection body on the one end side and has an outer diameter smaller than the outer diameter of the connection body.

6. The vibration actuator according to claim 4 or 5.

7. In the connection body, a recess is formed around the supporting and fixing portion at a portion from which the supporting and fixing portion protrudes. The vibration actuator according to claim 6.

8. The recess is an annular groove that surrounds the periphery of the support and fixation part. The vibration actuator according to claim 7.

9. the weight portion is stacked on the magnet and the yoke so that the weight portion is disposed at a position on the fixed body that does not face an outer yoke that surrounds the coil when the movable body is at a maximum amplitude position in a vibration direction, The weight portion is made of a non-magnetic material. The vibration actuator according to claim 1 .

10. A handheld or wearable electrical device, a vibration actuator according to any one of claims 1 to 7 mounted on a contact portion with a user; Electrical equipment.

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