Vibration actuator and electronic apparatus

Abstract

The invention provides a vibration actuator having impact resistance and capable of outputting suitable somatosensory vibration, and an electronic device. A vibration actuator is provided with: a movable body having a coil and one of magnets disposed on the inside in the radial direction of the coil at a distance from the inside in the radial direction of the coil; a fixed body having the other of the coil and the magnet and having a shaft portion inserted through the movable body; and an elastic support portion that supports the movable body so as to be movable with respect to the fixed body. The movable body vibrates in the vibration direction with respect to the fixed body due to the cooperation of the coil to which power is supplied and the magnet, the movable body has a through-hole through which the shaft portion is inserted and which forms a gap with the outer peripheral surface of the shaft portion, and the elastic support portion supports the movable body so as not to come into contact with the shaft portion when the movable body is not vibrated and when the movable body is vibrated.

Description

[0001] This application is a divisional application: the application number of its parent case is "201910152974.4", and the invention title is "Vibration actuator and electronic device". Technical Field

[0002] The present invention relates to a vibration actuator and an electronic device including the vibration actuator. Background Art

[0003] Currently, a vibration actuator is installed in an electronic device having a vibration function as a vibration generation source. The electronic device drives the vibration actuator to transmit vibration to the user to give the user a physical sensation, so as to be able to notify incoming messages, or improve the operation feeling and presence feeling. Here, the electronic device includes portable mobile devices such as a mobile game terminal, a controller (gamepad) of a fixed game console, a mobile phone, a smart phone and other mobile communication terminals, a mobile information terminal such as a tablet PC, and a wearable terminal worn on clothes, arms, etc.

[0004] As a vibration actuator having a structure that can be miniaturized and installed in a mobile device, for example, a vibration actuator used for a pager as shown in Patent Document 1 is well known.

[0005] In this vibration actuator, a pair of plate-shaped elastic bodies are supported by a frame in a facing manner, and at the central portion of the protrusion of one of the pair of plate-shaped elastic bodies having a spiral shape, a yoke having a magnet mounted thereon is fixedly supported. The yoke and the magnet together constitute a magnetic field generating body, and a coil is arranged in the magnetic field of the magnetic field generating body in a state of being mounted on the other plate-shaped elastic body. By applying currents with different frequencies to the coil through an oscillation circuit, the pair of plate-shaped elastic bodies selectively resonate to generate vibration, and the yoke vibrates in the center line direction of the frame.

[0006] In this vibration actuator, the distances between the magnet and the coil and between the yoke and the coil are made larger than the distance between the yoke and the inner peripheral wall of the frame. Thus, in the case of being impacted from the outside, first, the yoke collides with the inner peripheral wall of the frame, so that the yoke and the magnet do not come into contact with the coil, preventing damage to the coil.

[0007] However, in reality, since the yoke having a magnet collides with the frame, there is a concern that the pair of plate-shaped elastic bodies elastically supporting the movable body having the yoke may be damaged by the impact.

[0008] Therefore, Patent Document 1 also discloses the following structure: a shaft for slidably moving the movable body in the vibration direction is provided on the fixed body, so that even when impacted from the outside, the yoke as the movable body does not move to the inner peripheral surface of the frame due to the shaft, preventing collision with the frame.

[0009] Prior Art Documents

[0010] Patent Document

[0011] Patent Document 1: Japanese Patent Laid-Open No. 10-117472 Summary of the Invention

[0012] Problems to be Solved by the Invention

[0013] However, in the structure of an existing vibration actuator in which a shaft for sliding a movable body is provided on a fixed body, the movement of the movable body can be restricted by the shaft to improve impact resistance. However, since the movable body slides along the shaft portion during driving, there is a concern about generating sliding noise.

[0014] Due to problems such as vibration noise generated by contact, the vibration performance of the vibration actuator itself is reduced. Therefore, for a vibration actuator that vibrates by the movement of a movable body, it is desired to output in a state where vibration noise is not included and the vibration performance is improved, and transmit it to the user so that the user can fully feel the vibration, that is, it is desired to output appropriate tactile vibration.

[0015] The present invention has been completed in view of the above aspects, and an object thereof is to provide a vibration actuator and an electronic device that have impact resistance and can output appropriate tactile vibration.

[0016] Means for Solving the Problems

[0017] One aspect of the vibration actuator of the present invention adopts the following structure.

[0018] The vibration actuator includes: a movable body having one of a coil and a magnet disposed at a space from the coil on the radially inner side of the coil; a fixed body having the other of the coil and the magnet and having a shaft portion inserted through the movable body; and an elastic support portion that supports the movable body so as to be movable relative to the fixed body. Through the cooperation of the energized coil and the magnet, the movable body vibrates in the vibration direction relative to the fixed body.

[0019] The vibration actuator is characterized in that

[0020] The movable body has a through hole through which the shaft portion is inserted and a gap is formed between the through hole and the outer peripheral surface of the shaft portion.

[0021] The elastic support portion supports the movable body so as not to contact the shaft portion when the movable body is not vibrating and when vibrating.

[0022] One aspect of the electronic device of the present invention adopts a structure in which the vibration actuator having the above structure is installed.

[0023] In addition, another aspect of the vibration actuator of the present invention adopts the following structure.

[0024] It has: a movable body having one of a coil and a magnet disposed radially inside the coil at a non-contact interval; a fixed body having the other of the coil and the magnet and having a shaft portion inserted through the movable body; and an elastic support portion that supports the movable body so as to be movable relative to the fixed body in a vibration direction corresponding to a direction in which the shaft portion extends, such that the movable body vibrates due to the cooperation of the coil and the magnet to which power is supplied.

[0025] The movable body has a through hole through which the shaft portion is inserted and a gap is formed between the outer peripheral surface of the shaft portion over the entire length of the movable body in the vibration direction.

[0026] The elastic support portion is a plurality of leaf springs, and the plurality of leaf springs are disposed separately in the vibration direction so as to sandwich the center of gravity of the movable body and extend in a direction intersecting the vibration direction respectively.

[0027] At each end of the movable body in the vibration direction, an opening edge portion of the through hole is provided so as to project cylindrically in the vibration direction from a cylindrical protrusion. The inner peripheral portions of the plurality of leaf springs are externally fitted to the opening edge portion, and the leaf springs are combined orthogonally to the vibration direction in a state where the shaft portion is inserted through the inner peripheral portions.

[0028] The plurality of leaf springs support the movable body so that the movable body does not contact the shaft portion over the entire length during non-vibration and vibration of the movable body.

[0029] The effects of the invention are as follows.

[0030] According to the present invention, it is possible to have impact resistance and output appropriate tactile vibrations. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a longitudinal sectional view showing a vibration actuator according to an embodiment of the present invention.

[0032] Figure 2 It is a top view exploded perspective view showing a state after removing the movable body in the vibration actuator.

[0033] Figure 3 It is a bottom view exploded perspective view showing a state after removing the movable body in the vibration actuator.

[0034] Figure 4 It is an overall exploded perspective view of the vibration actuator.

[0035] Figure 5 It is a perspective view showing the movable body and the elastic support portion of the vibration actuator.

[0036] Figure 6 This is a diagram for explaining a modified example of the joining structure of the elastic support portion and the housing.

[0037] Figure 7 This is a diagram showing an example of the fixed position of the elastic support portion for explanation.

[0038] Figure 8 This is a diagram for explaining resonance.

[0039] Figure 9 This is a cross-sectional view showing the magnetic circuit structure of the above-described vibration actuator.

[0040] Figure 10 This is a diagram showing an example of an electronic device equipped with the above-described vibration actuator.

[0041] Figure 11 This is a diagram showing an example of an electronic device equipped with the above-described vibration actuator.

[0042] Explanation of Signs

[0043] 10, 10A, 10B, 10C - Vibration actuator, 20 - Movable body, 20a - Through hole, 21 - Movable body iron core, 21a - Opening portion, 21b, 29b - Spring fixing portion, 21c, 29a - Countersunk hole portion, 24, 25 - Bushing, 27 - Central yoke portion, 29 - Balance weight portion, 292 - Cylindrical protrusion, 40 - Fixed body, 42 - Frame, 43 - Upper housing, 431, 451 - Bottom, 433, 453 - Step portion, 44 - Coil holder, 441 - Outer cylinder portion, 441a, 441b - Ring-shaped fitting portion, 442 - Inner bottom, 443 - Inner cylinder portion, 45 - Lower housing, 46, 47 - Buffer, 48a, 48b - Elastic ring member (attenuation member), 50 - Shaft (shaft portion), 60 - Elastic support portion, 602 - Outer peripheral portion, 604 - Inner peripheral portion, 606 - Arm, 62 - Upper side leaf spring (elastic support portion), 64 - Lower side leaf spring (elastic support portion), 70 - Coil, 80 - Magnet, 91, 92 - Attenuation member, 201 - Communication portion, 202 - Processing portion, 203 - Drive control portion, 212 - Flat portion, 214 - Ring-shaped portion. Detailed Embodiment

[0044] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0045] [Overall Structure of Vibration Actuator]

[0046] Figure 1 This is a longitudinal cross-sectional view showing the vibration actuator 10 according to an embodiment of the present invention. Figure 2is a top-down exploded perspective view showing the state after removing the movable body 20 from the above-described vibration actuator 10, Figure 3 is a bottom-up exploded perspective view showing the state after removing the movable body 20 from the above-described vibration actuator 10. And, Figure 4 is an overall exploded perspective view of the above-described vibration actuator, Figure 5 is a perspective view showing the movable body 20 and the elastic support portion 60 of the above-described vibration actuator 10. In addition, for ease of understanding, the "upper" side and "lower" side in the present embodiment are noted for convenience and refer to one side and the other side in the vibration direction of the movable body 20 in the vibration actuator 10. That is, when the vibration actuator 10 is mounted on an electronic device (refer to Figure 10 , Figure 11 ), it can be upside down or left-right reversed.

[0047] Figures 1 to 4 The vibration actuator 10 shown is installed as a vibration generation source in an electronic device, specifically a mobile game terminal (such as Figure 10 's game controller GC), or a mobile device such as a smartphone (such as Figure 11 's mobile terminal M), to realize the vibration function of the mobile device. The vibration actuator 10 is driven, for example, when notifying the user of an incoming message or giving an operation feeling and a sense of presence.

[0048] The vibration actuator 10 includes: a movable body 20 having a magnet 80; an elastic support portion 60; and a fixed body 40 having a coil 70 and supporting the movable body 20 so as to be reciprocally movable via the elastic support portion 60.

[0049] In the vibration actuator 10, the coil 70 and the magnet 80 constitute a magnetic circuit that vibrates the movable body 20. In the vibration actuator 10, power is supplied from a power supply unit (such as Figure 10 , Figure 11 's drive control unit 203) to the coil 70, and the coil 70 cooperates with the magnet 80 to reciprocally vibrate the movable body 20 relative to the fixed body 40 in the vibration direction.

[0050] The vibration actuator 10 of the present embodiment reciprocally vibrates the movable body 20 along the magnetization direction of the magnet 80 (corresponding to the extending direction of the shaft 50 or the axial direction of the coil 70). In the vibration actuator 10, when the movable body 20 is non-movable and non-vibrating, it is supported via the elastic support portion 60 so as not to contact the shaft (shaft portion) 50, and even when movable, it is supported via the elastic support portion 60 so as not to contact the shaft 50. The vibration actuator 10 holds the movable body 20 so as not to contact the shaft 50 during non-vibration and vibration. The vibration actuator 10 of the present embodiment also includes magnetic fluids C1, C2 disposed between the fixed body 40 and the movable body 20.

[0051] In addition, the vibration actuator 10 of the present embodiment has a so-called moving magnet structure, that is, a coil 70 is provided on the fixed body 40 side and a magnet 80 is provided on the movable body 20 side to make the magnet 80 side movable, but it is not limited thereto. It may also be a moving coil structure, that is, a coil 70 is provided on the movable body 20 and a magnet 80 is provided on the fixed body 40 side.

[0052] In the vibration actuator 10 of the present embodiment, as Figure 5 shown, the elastic support portion 60 is a plurality of leaf springs (upper leaf spring 62, lower leaf spring 64) separately mounted on the movable body 20 in the vibration direction. The upper leaf spring 62 and the lower leaf spring 64 will be described in detail below.

[0053] <Movable body 20>

[0054] Figures 1 to 4 As shown, the movable body 20 is supported by the elastic support portion 60 between the upper housing 43 and the lower housing 45 of the fixed body 40 so as to be able to reciprocate in the direction in which the upper housing 43 and the lower housing 45 face each other along the shaft 50 inserted through the through hole 20a formed in the central portion (refer to Figure 1 ).

[0055] In the movable body 20, the through hole 20a is provided so as to penetrate in the vibration direction, and in the present embodiment, it penetrates in the vertical direction. In the through hole 20a, the shaft 50 spanned between the upper and lower housings 43 and 45 of the fixed body 40 is inserted in such a manner that the outer peripheral surface of the shaft 50 does not contact the inner peripheral surface of the through hole 20a.

[0056] In the present embodiment, the movable body 20 includes a movable body iron core 21, a bushing 24, a magnet 80, a bushing 25, a center yoke portion 27, and a balance weight portion 29. In the movable body 20, the magnet 80, the center yoke portion 27, and the balance weight portion 29 are inserted through the shaft 50 with a gap G and are continuously provided in the vibration direction. In the movable body 20 of the present embodiment, the magnet 80 is clamped between the flat portion 212 of the movable body iron core 21 and the center yoke portion 27, and the balance weight portion 29 is provided on the center yoke portion 27 side. Openings are provided at the centers of the movable body iron core 21, the bushing 24, the magnet 80, the bushing 25, the center yoke portion 27, and the balance weight portion 29, and the openings are coaxially and continuously arranged to form the through hole 20a of the movable body 20. The shaft 50 is inserted through the openings of the continuously arranged movable body iron core 21, bushing 24, magnet 80, bushing 25, center yoke portion 27, and balance weight portion 29 in a manner that allows movement so as to form a gap G between the inner peripheral surface of the through hole 20a and the outer peripheral surface of the shaft 50.

[0057] A magnet 80 is fixed to the movable iron core 21. The movable iron core 21 is arranged to cover the coil 70 fixed to the fixed body 40 side together with the fixed magnet 80 from the outer peripheral side and the upper surface side. The movable iron core 21 constitutes the outer peripheral part of the movable body 20.

[0058] In the present embodiment, the movable iron core 21 is a magnetic body having a covered cylindrical portion composed of a flat plate portion 212 and an annular portion 214. The flat plate portion 212 and the annular portion 214 are arranged to surround the magnet 80 disposed inside these components and function as a yoke portion. In the present embodiment, the movable iron core 21 is arranged at a position covering the coil 70 also disposed on the outer peripheral side of the magnet 80.

[0059] The movable iron core 21 is made of a magnetic material and together with the coil 70, the magnet 80, and the central yoke portion 27 constitutes a magnetic circuit. The movable iron core 21 has functions as the main body part of the movable body 20, as a part of the magnetic circuit, and as a weight in the movable body 20.

[0060] The flat plate portion 212 of the movable iron core 21 is an annular plate-like body, and an opening 21a (corresponding to the through-hole 20a) for inserting the shaft 50 is formed in the center. The magnet 80 is fixed to the lower surface (back surface) of the flat plate portion 212, and the annular portion 214 is fixed so as to protrude downward from the outer peripheral portion of the flat plate portion 212.

[0061] On the upper surface (front surface) side of the flat plate portion 212, a cylindrical protrusion 216 protruding upward is provided. A spring fixing portion 21b is formed at the upper end portion of the cylindrical protrusion 216 and has an annular shape extending in the circumferential direction along the opening edge portion. The inner spring end portion, that is, the inner peripheral portion 604 of the upper side leaf spring 62 is joined to the spring fixing portion 21b.

[0062] A concave counterbore portion 21c is provided on the lower surface of the flat plate portion 212 and at the opening edge portion. A bushing 24 functioning as a contact member is disposed in the counterbore portion 21c.

[0063] The bushing 24 can also be press-fitted and embedded into the counterbore portion 21c. The bushing 24 as the contact member functions as a contact portion that contacts when the shaft 50 inserted into the through-hole 20a is displaced in the movable body 20. The contact member is formed of a low-rigidity material such as resin or elastomer, buffers the impact force when contacting the shaft 50, and can prevent the shaft 50 from being damaged. In the present embodiment, the bushing 24 as the contact member and the bushing 25 assembled to the balance weight portion 29 are formed together into an annular shape, and when the movable body 20 is not vibrating, the shaft 50 is inserted through axially with a gap G formed on its outer periphery and is movable freely.

[0064] The bushing 24 as a contact member has an inner peripheral surface that faces the outer peripheral surface of the shaft 50 with a gap G therebetween. The inner peripheral surface of the bushing 24 is a part of the inner peripheral surface of the movable body 20 that, together with the inner peripheral surface of the bushing 25, defines the through hole 20a.

[0065] The annular portion 214 is a cylindrical body. In the present embodiment, the opening edge portion, which is the lower end portion of the opening, is located at a position facing the outer peripheral surface side of the coil 70 and separated from the central portion in the axial direction of the coil 70. The movable core 21 is disposed at a position covering the magnet 80 on the outer peripheral side and the upper surface side of the magnet 80 and covering the upper side of the coil 70.

[0066] The opening edge portion of the annular portion 214 is disposed to face the inner bottom portion 442 within the coil holder 44 with a predetermined interval therebetween. By this predetermined interval, a movable region of the movable body 20 in its vibration direction can be ensured.

[0067] The magnet 80 is formed in a cylindrical shape and is magnetized in the vibration direction, which is the two opening directions in the present embodiment (i.e., the extending direction of the shaft 50, corresponding to the axial direction of the coil 70). In the present embodiment, the magnet 80 is formed such that the upper side is the S pole and the lower side is the N pole. The magnet 80 is fixed to the flat portion 212 of the movable core 21 using a thermosetting adhesive such as epoxy resin.

[0068] The magnet 80 is disposed relative to the coil 70 at a position spaced a predetermined interval radially inward of the coil 70. Here, the "radial direction" is the direction orthogonal to the axis of the coil 70. The "predetermined interval" in this radial direction is the interval at which the magnet 80 and the coil 70 can move without contacting each other in the magnetization direction. In the present embodiment, it refers to the interval between the coil 70 side including the thickness of the inner cylindrical portion 443 inside the coil 70 and the magnet 80.

[0069] As Figure 1 shown, in the present embodiment, the magnet 80 is disposed such that the radially outer side of its lower portion faces the upper portion of the coil 70. In addition, the magnet 80 may be disposed such that the two magnetization surfaces face each other in the extending direction of the axis of the coil 70 inside the coil 70, and it may have a shape other than a cylindrical shape.

[0070] The center yoke portion 27 is disposed in close contact with the magnet 80 to concentrate the magnetic flux of the magnet 80 so that the magnetic flux does not leak and flows efficiently. In the present embodiment, the center yoke portion 27 is disposed such that, when the movable body 20 is not vibrating, inside the coil 70 (radially inward), it faces the coil 70 in a direction orthogonal to the axial direction (vibration direction) of the coil 70 at the central portion of the coil 70.

[0071] The balance weight portion 29 increases the vibration output of the movable body 20 and fixes the lower leaf spring 64 serving as the elastic support portion 60.

[0072] In the present embodiment, the balance weight portion 29 has a cylindrical shape and is continuously provided with the center yoke portion 27 along the vibration direction, i.e., the axis 50, by bonding or the like. The balance weight portion 29 is fixed to the center yoke portion 27 using a thermosetting adhesive such as epoxy resin, for example.

[0073] The balance weight portion 29 is provided below the center yoke portion 27 as a component that also serves as a spring fixing portion for fixing the lower side leaf spring 64 and a balance weight. Thus, there is no need to assemble components having a balance weight function and a spring fixing function separately, and by simply providing the balance weight portion 29, the lower side leaf spring 64 can be easily assembled, and the assemblability can be improved. Also, since the balance weight portion 29 is not provided on the outer peripheral side of the movable body 20, the arrangement space of the coil located on the outer peripheral side of the movable body 20 is not limited, and thus the efficiency of electromagnetic conversion is not reduced. Therefore, the weight of the movable body 20 can be appropriately increased, and a high vibration output can be achieved.

[0074] The balance weight portion 29 may be made of a magnetic material, but it is preferably made of a non-magnetic material. If the balance weight portion 29 is made of a non-magnetic material, the magnetic flux from the upper center yoke portion 27 does not flow downward, and can efficiently pass through the coil 70 located on the outer peripheral side of the center yoke portion 27.

[0075] The balance weight portion 29 is preferably formed of a material having a specific gravity higher than that of materials such as a stainless steel plate (SUS, the specific gravity of the steel plate is 7.70 to 7.98) (for example, about 16 to 19). Tungsten can be applied as the material of the balance weight portion 29, for example. Thus, even when the external dimensions of the movable body 20 are set in the design or the like, the mass of the movable body 20 can be relatively easily increased, and thus the desired vibration output that provides sufficient tactile vibration to the user can be achieved.

[0076] On the surface of the balance weight portion 29 on the side of the center yoke portion 27, a concave counterbore portion 29a formed at the opening edge portion is provided. In the counterbore portion 29a, a bushing 25 that functions in the same manner as the bushing 24 is disposed as a contact member. The bushing 25 may also be press-fitted into the counterbore portion 29a. Also, on the surface of the balance weight portion 29 opposite to the center yoke portion 27 (lower surface), a spring fixing portion 29b is provided so as to project from the periphery of the opening portion. The inner spring end portion, i.e., the inner peripheral portion 604, of the lower side leaf spring 64 of the elastic support portion 60 is joined to the spring fixing portion 29b. The spring fixing portion 29b is formed at the front end of a cylindrical protrusion 292 that projects toward the lower surface side of the balance weight portion 29 main body. A step is formed between the balance weight portion 29 main body and the spring fixing portion 29b by the protruding length of the cylindrical protrusion 292. This step forms an elastic deformation region of the lower side leaf spring 64 that extends radially outward from the spring fixing portion 29b.

[0077] In the above structure, in the present embodiment, the inner peripheral surfaces of the bushings 24 and 25 are separated from the outer peripheral surface of the shaft 50 together, and are disposed at positions closer to the outer peripheral surface of the shaft 50 than the inner peripheral surfaces of the movable body iron core 21, the magnet 80, the center yoke portion 27, and the balance weight portion 29. Thus, when the shaft 50 in the through hole 20a of the movable body 20 moves relative to the movable body 20, the shaft 50 that collides with the inner peripheral surface of the specified through hole 20a comes into contact with the bushings 24 and 25 that form a part of the inner peripheral surface of the through hole 20a. Therefore, the impact on both the fixed body 40 side of the movable body iron core 21, the magnet 80, the center yoke portion 27, and the balance weight portion 29 and the shaft 50 is alleviated, and particularly, breakage of the shaft 50 can be prevented.

[0078] Moreover, since the bushings 24 and 25 are embedded inside the counterbore portions 21c of the movable body iron core 21 and the counterbore portions 29a of the balance weight portion 29, the components of the movable body iron core 21 and the magnet 80, and the center yoke portion 27 and the balance weight portion 29 are continuously provided in a state of being in close contact with each other in the annular surfaces that abut against each other.

[0079] Also, the bushings 24 and 25 are disposed between the components of the movable body iron core 21 and the magnet 80, and the center yoke portion 27 and the balance weight portion 29, so as not to come off axially.

[0080] <Fixed body 40>

[0081] In the present embodiment, the fixed body 40 has the coil 70 among the coil 70 and the magnet 80 (refer to Figure 1 , Figure 4 ), and has a shaft 50 inserted through the movable body 20.

[0082] The fixed body 40 has a frame body 42 that surrounds the movable body 20, and the shaft 50 is inserted through the through hole 20a of the movable body 20 accommodated in the box body 42 and fixed to the frame body 42.

[0083] In the present embodiment, the frame body 42 is a hollow cylinder. The frame body 42 has: a cylindrical coil holder 44 that holds the coil 70 and surrounds the movable body 20; an upper housing 43 and a lower housing 45 that fix the both ends of the shaft 50 and block the openings at both ends of the coil holder 44, respectively.

[0084] In the vibration actuator 10, the coil 70 uses the axial direction (the magnetization direction of the magnet 80) as the vibration direction and is used together with the magnet 80 to generate a driving source for the vibration actuator 10. The coil 70 is energized during driving and forms a voice coil motor together with the magnet 80.

[0085] The axis of the coil 70 is arranged coaxially with the axis of the magnet 80, for example, along the axial direction of the magnet 80 (the extending direction of the shaft 50).

[0086] The coil 70 is arranged such that the central position of the length in its vibration direction is at substantially the same height position as the central position of the length in the vibration direction of the central yoke 27.

[0087] Both ends of the coil 70 are connected to a power supply unit (such as Figure 10 , Figure 11 the drive control unit 203 shown). For example, both ends of the coil 70 are connected to an AC supply unit, and an AC power supply (AC voltage) is supplied from the AC supply unit to the coil 70. Thereby, a thrust that can move in the direction of approaching and separating from each other in the axial direction between the coil 70 and the magnet can be generated.

[0088] In the magnet 80, when magnetized such that the flat plate portion 212 side (the upper side in the present embodiment) is the S pole and the central yoke 27 side is the N pole, magnetic fluxes are formed that radiate from the joint portion between the magnet 80 and the central yoke 27 and the central yoke 27 and enter from the flat plate portion 212 side. Therefore, for any part of the coil 70 arranged to surround the magnet 80 and the central yoke 27, the magnetic fluxes cross from the inner side to the outer side in the radial direction of the coil 70. Thus, when the coil 70 is energized, Lorentz forces act in the same direction ( Figure 9 the F direction shown in, or the -F direction).

[0089] The shaft 50 has impact resistance capable of withstanding the impact when displaced within the through hole 20a of the movable body 20 and contacting the inner peripheral surface of the through hole 20a, specifically the bushings 24 and 25 as contact members.

[0090] Both ends of the shaft 50 are respectively fixed to the upper housing 43 and the lower housing 45 such that the shaft 50 itself is located on the central axis of the housing 42. And the shaft 50 is preferably a shaft made of a non-magnetic material. If the shaft 50 is made of a magnetic material, a magnetic attraction force is generated between it and the magnet 80, and thus it is difficult to maintain the gap between the shaft 50 and the magnet 80 during assembly etc. By forming the shaft 50 of a non-magnetic material, no magnetic attraction force is generated, and an appropriate gap (clearance) G can be maintained between the shaft 50 and the movable body 20 (specifically the through hole 20a).

[0091] The upper housing 43, the lower housing 45, and the coil holder 44 are respectively made of a metal material such as SUS (stainless steel) having impact resistance. The upper housing 43, the lower housing 45, and the coil holder 44 are preferably made of the same metal (for example, SUS (stainless steel) 304).

[0092] The coil holder 44 surrounds the movable body 20 from the outer peripheral side and holds the coil 70 while surrounding the coil 70 on the outer peripheral side of the magnet 80.

[0093] Specifically, in the coil holder 44, as Figure 1 , Figure 3As shown, a circular inner bottom portion 442 is provided so as to project from the inner peripheral surface of a cylindrical outer cylinder portion 441 whose two openings are blocked by an upper housing 43 and a lower housing 45 toward the axis side of the coil holder 44. An inner cylinder portion 443 is provided in the inner diameter portion of the inner bottom portion 442 so as to stand along the axial direction.

[0094] The inner cylinder portion 443 is formed into a cylindrical shape that faces the outer peripheral surface of the movable body 20 with a predetermined interval therebetween. Here, the "predetermined interval" is an interval that allows the magnet 80 to move relative to the coil 70. The movable body 20 vibrates along the vibration direction inside the inner cylinder portion 443. The coil 70 disposed on the inner bottom portion 442 is externally fitted to the outer peripheral surface of the inner cylinder portion 443.

[0095] The inner cylinder portion 443 and the inner bottom portion 442 hold the coil 70 on the outer peripheral side of the magnet 80 with a space therebetween. In other words, the coil holder 44 holds the coil 70 such that the magnet 80 is located on the radially inner side of the coil 70 with a predetermined interval and coaxially.

[0096] At the opening end portions, i.e., the upper and lower end portions, of the coil holder 44, annular fitting portions 441a, 441b that are fitted to the respective openings of the upper housing 43 and the lower housing 45 are provided.

[0097] The upper housing 43 and the lower housing 45 are each formed into a bottomed cylindrical shape, and the respective bottom portions 431, 451 constitute the top surface and the bottom surface of the vibration actuator 10 in the present embodiment. In addition, the upper housing 43 and the lower housing 45 may be formed into a concave shape by stretching a metal plate.

[0098] The bottom portion 431 of the upper housing 43 and the bottom portion 451 of the lower housing 45 are disk-shaped bodies, and openings 432, 452 that face each other are formed in the central portions thereof. Both end portions of the shaft 50 are inserted and fixed into the respective openings 432, 452. The fixing of both end portions of the shaft 50 to the openings 432, 452 can be performed by press-fitting the shaft 50 into the openings 432, 452, or can be performed by adhesion or welding. Further, the shaft 50 can be fixed to the frame 42 by combining the above press-fitting, adhesion, and welding.

[0099] Moreover, on the circumferential wall portions of the upper housing 43 and the lower housing 45, annular step portions 433, 453 (see Figures 1 to 4 ) that extend in the circumferential direction at positions away from the respective bottom portions 431, 451 are provided. The lengths from the respective bottom portions 431, 451 to the step portions 433, 453 can respectively define the movable range of the movable body 20.

[0100] The stepped portions 433 and 453 have shapes that fit into the annular fitting portions 441a and 441b of the coil holder 44. Further, the stepped portions 433 and 453, together with the annular fitting portions 441a and 441b, fix the elastic support portion 60. The fixing structure will be described in detail below.

[0101] The buffers 46 and 47 are buffer members that mitigate the impact when the movable body 20 contacts the fixed body 40 during movement. The buffers 46 and 47 are respectively disposed between the upper housing 43 and the movable body 20, and between the lower housing 45 and the movable body 20, and contact the movable body 20 at the maximum amplitude of the movable body 20 that is movable within the housing 42.

[0102] In the present embodiment, the buffers 46 and 47 are respectively provided on the inner surfaces of the bottom portions 431 of the upper housing 43 and the bottom portions 451 of the lower housing 45. The buffers 46 and 47 are formed of, for example, sponge or the like, are formed in a ring shape, and are fixed to the peripheral portions of the respective openings 432 and 452 on the inner surfaces of the bottom portions 431 and 451, that is, the mutually opposed surfaces.

[0103] When the movable amplitude of the movable body 20 in the vibration actuator 10 becomes large, or when an impact is received from the outside, the buffers 46 and 47 can prevent abnormal noise caused by the contact of the movable body 20 with the upper housing 43 and the lower housing 45, or prevent breakage of each component due to the impact.

[0104] <Elastic support portion 60>

[0105] The elastic support portion 60 is connected to both the movable body 20 and the fixed body 40, and supports the movable body 20 so as to be movable relative to the fixed body 40.

[0106] The elastic support portion 60 supports the movable body 20 so as not to contact the shaft 50 when the movable body 20 is not vibrating and when it is vibrating. The elastic support portion 60 only needs to be a member that elastically supports the movable body 20 so as to be movable, and may have any configuration.

[0107] The elastic support portion 60 may have one, or may have two or more. The elastic support portion 60 is a plate-shaped elastic support body, and is, for example, a plurality of leaf springs formed by processing a stainless steel plate.

[0108] In the present embodiment, the elastic support portion 60 is an upper side leaf spring 62 and a lower side leaf spring 64 that are installed in such a manner as to sandwich the movable body 20 at positions separated in the vibration direction.

[0109] The upper side plate spring 62 and the lower side plate spring 64 are thin disc-shaped spiral springs (coil springs) formed by sheet metal processing. The spiral upper side plate spring 62 and lower side plate spring 64 have a shape in which the outer peripheral portion 602 as the outer spring end and the inner peripheral portion 604 as the inner spring end are joined by an arc-shaped arm 606, and the outer peripheral portion 602 and the inner peripheral portion 604 can be displaced relative to each other in the axial direction of the elastic support portion.

[0110] In the present embodiment, the spirals of the plurality of upper side plate springs 62 and lower side plate springs 64 are in the same direction. One end on the outer peripheral side, i.e., the outer peripheral portion 602, of each is fixed to the fixed body 40, and the other end on the inner peripheral side, i.e., the inner peripheral portion 604, is fixed to the movable body 20.

[0111] When using a plurality of spiral-shaped leaf springs and respectively installing them at both ends of the movable body 20 separated in the vibration direction, when elastically supporting the movable body relative to the fixed body, if the amount of movement of the movable body 20 becomes larger, the movable body moves along the translation direction (here, the direction on the plane perpendicular to the vibration direction) while slightly rotating. If the spirals of the plurality of leaf springs are in opposite directions, the plurality of leaf springs will act on each other in the buckling direction or the stretching direction, thus hindering smooth movement.

[0112] The upper side plate spring 62 and the lower side plate spring 64 of the present embodiment are fixed to the movable body 20 in such a manner that the spirals are in the same direction. Thus, even if the amount of movement of the movable body 20 becomes larger, it can move smoothly, that is, it can deform to a larger amplitude, and the vibration output can be improved.

[0113] In the upper side plate spring 62 and the lower side plate spring 64, the outer peripheral portion 602 is joined to the fixed body 40, and the inner peripheral portion 604 is joined to the movable body 20.

[0114] Specifically, the inner peripheral portions 604 of the upper side plate spring 62 and the lower side plate spring 64 are externally fitted to both ends (spring fixing portions 21b, 29b) separated in the axial direction (vibration direction) of the movable body 20, and are installed on the movable body 20 in such a manner that the outer peripheral portion 602 projects radially outward (radial direction). The inner peripheral portions 604 of the upper side plate spring 62 and the lower side plate spring 64 and the spring fixing portions 21b, 29b may also be joined by welding or bonding.

[0115] Moreover, the outer peripheral portions 602 of the upper side plate spring 62 and the lower side plate spring 64 are respectively fixed to the fixed body 40 on the radially outer side.

[0116] The outer peripheral portion 602 of the upper side plate spring 62 is joined at the fitting portion between the upper housing 43 and the coil holder 44, and the outer peripheral portion 602 of the lower side plate spring 64 is joined at the fitting portion between the coil holder 44 and the lower housing 45.

[0117] In the present embodiment, the upper side leaf spring 62 and the lower side leaf spring 64 are fixed to the fixed body 40 via damping members (such as elastic annular members 48a, 48b) that attenuate vibration.

[0118] The outer peripheral portion 602 of the upper side leaf spring 62 is disposed between the elastic annular member 48a disposed on the stepped portion 433 of the upper housing 43 and the annular fitting portion 441a, and is fixed in a state of being clamped by the stepped portion 433 and the annular fitting portion 441a. In addition, the elastic annular members 48a, 48b can be removed, and the elastic support portion 60 can be fixed between the stepped portions 433, 453 and the annular fitting portions 441a, 441b.

[0119] The elastic annular member 48a is formed of a soft material such as an elastic body, rubber, resin, or porous elastic body (such as sponge), and attenuates the vibration transmitted to the stepped portion 433 side via the upper side leaf spring 62 as the elastic support portion 60 when the movable body 20 moves.

[0120] In addition, the fixing of the outer peripheral portion 602 of the lower side leaf spring 64 to the housing 42 has the same structure as the fixing of the upper side leaf spring 62. That is, the outer peripheral portion 602 of the lower side leaf spring 64 is disposed between the elastic annular member 48b disposed on the stepped portion 453 of the lower housing 45 and the annular fitting portion 441b, and is fixed in a state of being clamped by the stepped portion 453 and the annular fitting portion 441b. In addition, the elastic annular member 48b is the same as the elastic annular member 48a and has the same function, so the description thereof is omitted.

[0121] When the upper side leaf spring 62 and the lower side leaf spring 64 are respectively disposed on the stepped portions 433, 453 via the elastic annular members 48a, 48b and the annular fitting portions 441a, 441b of the coil bracket 44 are fitted and assembled to the upper housing 43 and the lower housing 45, the front end portions of the annular fitting portions 441a, 441b push the upper side leaf spring 62 and the lower side leaf spring 64 toward the stepped portions 443, 453 side and fix them.

[0122] The joining between the outer peripheral portion 602 of the upper side leaf spring 62 and the lower side leaf spring 64 and the housing 42 (the upper housing 43, the lower housing 45, and the coil bracket 44) can be performed using an adhesive, welding, or press-fitting. Also, the two can be joined and fixed by appropriately combining bonding, press-fitting, and welding methods.

[0123] Here, Figure 6 A modified example of the structure in which the upper side leaf spring 62 and the lower side leaf spring 64, that is, the elastic support portion, are joined via the damping member to the housing 42 is shown.

[0124] Figure 6 is a diagram for explaining a modified example of the joining structure between the elastic support portion and the box body. Specifically, Figure 6It is a partial enlarged view showing the joint portion of the upper side plate spring 62, which is an example of the elastic support portion 60, and the frame body 42. As Figure 6 The outer peripheral portion 602 of the upper side plate spring 62 of the elastic support portion 60 shown is fixed to the frame body 42 via the damping members 91 and 92.

[0125] The damping members 91 and 92 are annular members formed of the same material as the elastic annular member 48a, and are disposed between the stepped portion 433 and the annular fitting portion 441a in a state of sandwiching the outer peripheral portion 602 in the axial direction (vibration direction).

[0126] In the vibration actuator 10 of the present embodiment, since it is considered that the movable body 20 constitutes the mass portion in the vibration model of the spring - mass system, the damping members 91 and 92 can suppress the intensity of resonance (refer to Figure 8 ), and can reduce the deviation generated by the maximum movement amount of the movable body 20.

[0127] The upper side plate spring 62 and the lower side plate spring 64 are fixed to the movable body 20 at the upper and lower end portions of the movable body 20 (which are the two end portions separated in the vibration direction and correspond to the spring fixing portions 21b and 29b) in a manner of sandwiching the center of gravity of the movable body 20.

[0128] Regarding the arrangement of the upper side plate spring 62 and the lower side plate spring 64, for example, they may be arranged on one side of the center of gravity of the movable body 20. However, in this case, the movable body 20 is fixed in a bell - shaped manner and is easily deflected with respect to the lateral force orthogonal to the vibration direction. Therefore, if it is desired to maintain a gap in the lateral direction (specifically, the gap between the outer cylinder portion 441 of the coil holder 44 and the annular portion 214 of the movable body core 21), a structure that requires a larger gap is formed, and the design freedom is greatly reduced.

[0129] In contrast, in the vibration actuator 10, the upper side plate spring 62 and the lower side plate spring 64 are fixed to the movable body 20 in a manner of sandwiching the center of gravity of the movable body 20. Therefore, when the vibration actuator 10 is tilted, the lateral deflection in the upper side plate spring 62 and the lower side plate spring 64 is reduced. Thus, even if the movable body 20 is held with a small gap, the movable body 20 can be driven without contacting the fixed body 40, and the design freedom of each component such as the movable body 20 and the fixed body 40 becomes higher. For example, the through - hole 20a of the movable body can be reduced, thereby enabling an increase in the mass of the movable body 20 and an increase in the vibration output to achieve an appropriate tactile vibration output.

[0130] Moreover, it is preferable that the intervals of the fixing portions of the upper side plate spring 62 and the lower side plate spring 64 are different on the fixed body 40 side and the movable body 20 side, respectively. That is, the upper side plate spring 62 and the lower side plate spring 64 are preferably arranged to elastically support the movable body 20 in a state of being loaded with a load, that is, in a state of being given a pre - load, when not vibrating.

[0131] Thus, at the initial position, i.e., when the movable body 20 is not vibrating, the spring constants of the upper side leaf spring 62 and the lower side leaf spring 64 are stable. Even if there are dimensional deviations or the like, they are given a preload and become stable. In this state, the upper side leaf spring 62 and the lower side leaf spring 64 are maintained. Therefore, the deviation in the form of the maximum deformation of the upper side leaf spring 62 and the lower side leaf spring 64 during movement is reduced.

[0132] Specifically, as Figure 7 shown, in the present embodiment, the upper side leaf spring 62 and the lower side leaf spring 64 are respectively fixed such that the length L2 between the spring fixing portions 21b and 29b fixed to the inner peripheral portion 604 is longer than the length L1 between the outer peripheral portions 602 of the fixing portions (the fitting portions including the stepped portions 433 and 453) fixed to the fixed body 40 side.

[0133] Moreover, in the engagement between the outer peripheral portion 602 of the upper side leaf spring 62 and the lower side leaf spring 64 and the housing 42 (the upper housing 43, the lower housing 45, and the coil holder 44), a damping member may also be interposed between the outer peripheral portion 602 and the coil holder 44 to further improve the vibration damping effect of the damping member including the elastic annular member 48a.

[0134] [Magnetic fluids C1, C2]

[0135] The magnetic fluid is disposed between the fixed body 40 and the movable body 20 to attenuate the vibration of the elastic support portion 60 (the upper side leaf spring 62 and the lower side leaf spring 64).

[0136] It is sufficient that the magnetic fluid is disposed between the fixed body 40 and the movable body 20, and it can be disposed at any position. For example, it is disposed at one or both of between the shaft 50 and the inner diameter portion of the magnet 80, and between the outer diameter portion of the magnet 80 and the inner diameter portion of the coil 70.

[0137] In the present embodiment, the magnetic fluid is disposed between the shaft 50 and the inner diameter portion (a part of the through hole 20a) of the magnet 80 (shown by the magnetic fluid C1), and between the outer diameter portion of the magnet 80 and the inner diameter portion (corresponding to the inner cylinder portion 443 in the present embodiment) of the coil 70.

[0138] In the vibration actuator 10 of the present embodiment, it is considered that the movable body 20 corresponds to the mass portion in the vibration model of the spring - mass system. In the case where resonance is intense as shown by the curve R1 in Figure 8 , i.e., in the case of having a steep peak, the steep peak is suppressed by attenuating the vibration. R2 shows the curve after attenuation. As shown by the curve R2, due to the attenuation of the vibration, the resonance is no longer steep, and there is no deviation in the maximum amplitude value and the maximum movement amount of the movable body 20 during resonance, so that vibration based on an appropriate and stable maximum movement amount can be output.

[0139] In the vibration actuator 10, a magnetic circuit as shown is formed. Also, in the vibration actuator 10, the coil 70 is arranged to be orthogonal to the magnetic flux from the central yoke portion 27 that is continuously provided with the magnet 80 of the movable body 20. Therefore, if energization is performed as shown Figure 9 a Lorentz force in the -F direction is generated in the coil 70 according to Fleming's left-hand rule by the interaction between the magnetic field of the magnet 80 and the current flowing through the coil 70. Figure 9 The direction of the Lorentz force in the -F direction is a direction orthogonal to the direction of the magnetic field and the direction of the current flowing through the coil 70 (

[0140] on the bottom 451 side of the lower housing 45 of the fixed body 40). Since the coil 70 is fixed to the fixed body 40 (coil bracket 44), according to the law of action and reaction, the force opposite to the Lorentz force in the -F direction acts as a thrust in the F direction on the movable body 20 having the magnet 80. Thus, the movable body 20 having the magnet 80 moves in the F direction, that is, toward the bottom 431 side of the upper housing 43. Figure 9 Moreover, if the energization direction of the coil 70 is switched to the opposite direction and the coil 70 is energized, a Lorentz force in the reverse F direction is generated. Due to the generation of this Lorentz force in the F direction, according to the law of action and reaction, the force opposite to this Lorentz force in the F direction acts as a thrust (thrust in the -F direction) on the movable body 20, and the movable body 20 moves in the -F direction, that is, toward the bottom 451 side of the lower housing 45 of the fixed body 40.

[0141] The vibration actuator 10 includes: a fixed body 40 having a coil 70 and a shaft 50; a movable body 20 having a magnet 80 that is magnetized in the axial direction of the coil 70 (which is the vibration direction and the extending direction of the shaft 50) and is arranged radially inside the coil 70; and an elastic support portion 60 (upper side leaf spring 62 and lower side leaf spring 64) that elastically supports the movable body 20 so as to be movable in the vibration direction. Also, the movable body 20 has a through hole 20a through which the shaft 50 is inserted and a gap G is formed between the through hole 20a and the outer peripheral surface of the shaft 50, and the elastic support portion 60 supports the movable body 20 so as not to contact the shaft 50 during non-vibration and vibration of the movable body 20.

[0142] Thus, during non-vibration and vibration when the movable body 20 is non-movable relative to the fixed body 40, the movable body 20 is supported with a gap G so as not to contact the shaft 50. Therefore, no noise generated by contact with the shaft 50, specifically, sliding, will occur during vibration of the movable body 20.

[0143]

[0144] ​Moreover, in the case where the vibration actuator 10 drops or the like, the movable body 20 contacts the shaft 50 only when an impact is applied to the vibration actuator 10 itself. That is, only when there is an impact, the movable body 20 and the shaft 50 relatively move within the range of the gap G between the through-hole 20a and the outer peripheral surface of the shaft 50, and the movable body 20 contacts the shaft 50 and its movement is restricted. Thus, according to the vibration actuator 10, different from the existing vibration actuators, the situation where the movable body 20 is displaced due to an impact applied to the vibration actuator and contacts the inner wall of the fixed body 40 (the outer cylinder portion 441 of the coil holder 44) and imparts an impact does not occur. That is, the inner wall of the fixed body 40 is not damaged due to the impact. Moreover, the elastic support portion 60 (the upper side leaf spring 62 and the lower side leaf spring 64) itself is not deformed due to the impact, and the malfunction such as the immovability of the movable body 20 caused by the deformation of the elastic support portion 60 (the upper side leaf spring 62 and the lower side leaf spring 64) can be eliminated.

[0145] Moreover, according to the vibration actuator 10, in the case of a design in which the shaft 50 is arranged at the center, the movement of the movable body 20 is restricted, and the impact resistance is improved, no sliding sound is generated during driving, and there is no concern that the vibration expressiveness is reduced due to the generation of noise caused by contact.

[0146] Thus, according to the vibration actuator 10, it is possible to have impact resistance and output a tactile vibration with high and appropriate vibration expressiveness.

[0147] Here, the vibration actuator 10 is driven by an alternating current wave input from a power supply unit (for example, Figure 10 , Figure 11 the drive control unit 203 shown) to the coil 70. That is, the energization direction of the coil 70 is periodically switched, and a thrust in the F direction on the bottom 431 side of the upper housing 43 and a thrust in the F direction on the bottom 451 side of the lower housing 45 are alternately applied to the movable body 20. As a result, the movable body 20 vibrates in such a manner that it does not contact the shaft 50 in the vibration direction (the winding axis direction orthogonal to the radial direction of the coil 70, the extending direction of the shaft 50, or the magnetization direction of the magnet 80).

[0148] Hereinafter, the drive principle of the vibration actuator 10 will be briefly described. In the vibration actuator 10 of the present embodiment, when the mass of the movable body 20 is set to m [kg] and the spring constant in the torsional direction of the spring (leaf spring) is set to K sp , the movable body 20 vibrates at a resonance frequency f r [Hz] calculated by Equation (1) with respect to the fixed body 40.

[0149] Equation 1

[0150]

[0151] Since the movable body 20 is considered to constitute the mass part in the vibration model of the spring-mass system, if an AC wave with a frequency equal to the resonance frequency f of the movable body 20 is input to the coil 70, the movable body 20 will enter a resonance state. That is, by inputting an AC wave with a frequency approximately equal to the resonance frequency f of the movable body 20 from the power supply unit to the coil 70, the movable body 20 can be vibrated efficiently. r The following shows the equation of motion and the circuit equation representing the driving principle of the vibration actuator 10. The vibration actuator 10 is driven based on the equation of motion shown in the following formula (2) and the circuit equation shown in formula (3). r Formula 2

[0152] m: mass [kg]

[0153] x(t): displacement [m]

[0154]

[0155]

[0156]

[0157] K f : thrust constant [N / A]

[0158] i(t): current [A]

[0159] K sp : spring constant [N / m]

[0160] D: damping coefficient [N / (m / s)]

[0161] Formula 3

[0162]

[0163] e(t): voltage [V]

[0164] R: resistance [Ω]

[0165] L: inductance [H]

[0166] K e : back electromotive force constant [V / (rad / s)]

[0167] That is, the mass m [kg], displacement x(t) [m], thrust constant K f [N / A], current i(t) [A], spring constant K sp [N / m], damping coefficient D [N / (m / s)], etc. in the vibration actuator 10 can be appropriately changed within the range that satisfies formula (2). And the voltage e(t) [V], resistance R [Ω], inductance L [H], back electromotive force constant K e[V / (rad / s)] can be appropriately changed within the range that satisfies Equation (3).

[0168] Thus, in the vibration actuator 10, when the coil 70 is energized with an alternating current corresponding to the resonance frequency f sp determined by the mass m of the movable body 20 and the spring constant K of the elastic support portion 60 as a leaf spring r a relatively large vibration output can be obtained efficiently.

[0169] Moreover, the vibration actuator 10 satisfies Equation (2) and Equation (3), and is driven by the resonance phenomenon using the resonance frequency shown in Equation (1). Thus, in the vibration actuator 10, the power consumed in the steady state only becomes the loss caused by the load torque and the loss caused by friction or the like, and it can be driven with low power consumption, that is, the movable body 20 can be linearly reciprocated with low power consumption.

[0170] Figure 10 , Figure 11 FIG. is an example showing the mounting form of the vibration actuator 10. Figure 10 An example in which the vibration actuator 10 is mounted on the game controller GC is shown, Figure 11 and an example in which the vibration actuator 10 is mounted on the mobile terminal M is shown.

[0171] The game controller GC is connected to the game console body by wireless communication, for example, and is used by being held or gripped by a user. The game controller GC has a rectangular plate shape here, and the user grasps the left and right sides of the game controller GC with both hands and operates it.

[0172] The game controller GC notifies the user of an instruction from the game console body by vibration. In addition, although not shown, the game controller GC has functions other than instruction notification, for example, an input operation unit for the game console body.

[0173] The mobile terminal M is a mobile communication terminal such as a mobile phone or a smartphone, for example. The mobile terminal M notifies the user of an incoming call from an external communication device by vibration, and realizes various functions of the mobile terminal M (for example, functions that give an operation feeling and a sense of presence).

[0174] As Figure 10 , Figure 11 shown, 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 the vibration actuator 10 as a drive unit, that is, vibration actuators 10A, 10B, and 10C. In addition, in the game controller GC, a plurality of vibration actuators 10A and 10B are mounted.

[0175] In the game controller GC and the mobile terminal M, the vibration actuators 10A, 10B, and 10C are installed, for example, such that the main surface of the terminal is parallel to the surface of the lower housing 45, which is orthogonal to the vibration direction of the vibration actuators 10A, 10B, and 10C. The main surface of the terminal is the surface that comes into contact with the user's body surface. In the present embodiment, it refers to the vibration transmission surface that comes into contact with the user's body surface to transmit vibration.

[0176] Specifically, in the game controller GC, the vibration actuators 10A and 10B are installed such that the surface contacted by the fingertips, finger pads, palms, etc. of the user performing operations or the surface provided with the operation unit is orthogonal to the vibration direction. Further, in the case of the mobile terminal M, the vibration actuator 10C is installed such that the display screen (touch panel surface) is orthogonal to the vibration direction. Thereby, vibration in a direction perpendicular to the main surface of the game controller GC and the mobile terminal M is transmitted to the user.

[0177] The communication unit 201 is connected to an external communication device via wireless communication, receives a signal from the communication device, and outputs it to the processing unit 202. In the case of the game controller GC, the external communication device is a game console main body that is an information communication terminal, and communication is performed according to a short-range wireless communication standard such as Bluetooth (registered trademark). In the case of the mobile terminal M, the external communication device is, for example, a base station, and communication is performed according to a mobile communication standard.

[0178] The processing unit 202 uses a conversion circuit unit (not shown) to convert the input signal into a drive signal for driving the vibration actuators 10A, 10B, and 10C and outputs it to the drive control unit 203. Further, in the mobile terminal M, the processing unit 202 generates a drive signal based not only on the signal input from the communication unit 201 but also on the signals input from various functional units (not shown, such as operation units like touch panels).

[0179] The drive control unit 203 is connected to the vibration actuators 10A, 10B, and 10C and is equipped with a circuit for driving the vibration actuators 10A, 10B, and 10C. The drive control unit 203 supplies a drive signal to the vibration actuators 10A, 10B, and 10C.

[0180] The vibration actuators 10A, 10B, and 10C are driven according to the drive signal from the drive control unit 203. Specifically, in the vibration actuators 10A, 10B, and 10C, the movable body 20 vibrates in a direction orthogonal to the main surface of the game controller GC and the mobile terminal M.

[0181] Whenever vibrating, the movable body 20 contacts the bottom 431 of the upper housing 43 or the bottom 451 of the lower housing 45 via the buffers 46 and 47. Therefore, the impact of the movable body 20 on the bottom 431 of the upper housing 43 or the bottom 451 of the lower housing 45 accompanying the vibration, that is, the impact on the housing 42, is directly transmitted to the user as vibration. Particularly in the game controller GC, since a plurality of vibration actuators 10A and 10B are installed, one or both of the plurality of vibration actuators 10A and 10B can be driven according to the input drive signal.

[0182] Since vibration in a direction perpendicular to the body surface is transmitted to the body surface of the user in contact with the game controller GC or the mobile terminal M, sufficient tactile vibration can be imparted to the user. In the game controller GC, tactile vibration for the user can be imparted by one or both of the vibration actuators 10A and 10B, and vibration with high expressiveness such as vibration with at least selectively adjustable strength can be imparted.

[0183] As described above, based on the embodiments, the invention made by the inventor has been specifically described. However, the present invention is not limited to the above embodiments and can be modified without departing from the gist thereof.

[0184] Moreover, for example, the vibration actuator of the present invention is applicable to cases of mobile devices (such as mobile information terminals such as tablet PCs, mobile game terminals, and wearable terminals worn by users) other than the game controller GC and the mobile terminal M shown in the embodiments. In addition to the above-mentioned mobile devices, the vibration actuator 10 of the present embodiment can also be applied to electric beauty instruments such as beauty massagers that require vibration.

[0185] Industrial Applicability

[0186] The vibration actuator of the present invention can have impact resistance and can exhibit appropriate tactile vibration, and is useful as a device mounted on an electronic device such as a game machine terminal or a mobile terminal that imparts vibration to the user.

Claims

1. A vibration actuator, characterized in that, it has: a movable body having one of a coil and a magnet disposed at a radial inner side of the coil with a space therebetween; a fixed body having the other of the coil and the magnet and having a shaft portion inserted through the movable body; and an elastic support portion that supports the movable body so as to be movable relative to the fixed body in a vibration direction corresponding to a direction in which the shaft portion extends, such that the movable body vibrates by cooperation of the energized coil and the magnet with respect to the fixed body, the movable body has a through hole through which the shaft portion is inserted and a gap is formed between the outer peripheral surface of the shaft portion over the entire length of the movable body in the vibration direction, the elastic support portion is a plurality of leaf springs, and the plurality of leaf springs are separately arranged in the vibration direction so as to sandwich the center of gravity of the movable body and extend in a direction intersecting the vibration direction respectively, at each end of the movable body in the vibration direction, an opening edge portion of the through hole is provided so as to project cylindrically in the vibration direction from a cylindrical protrusion, inner peripheral portions of the plurality of leaf springs are externally fitted to the opening edge portion, and the leaf springs are joined orthogonally to the vibration direction in a state where the shaft portion is inserted through the inner peripheral portions, the plurality of leaf springs support the movable body such that the movable body does not contact the shaft portion over the entire length during non-vibration and vibration of the movable body.

2. The vibration actuator according to claim 1, characterized in that, the plurality of leaf springs as the elastic support portion are spiral springs having the same shape, the directions of the respective spirals are the same direction, one end on the outer peripheral side of each is fixed to the fixed body, and the other end on the inner peripheral side is fixed to the movable body.

3. The vibration actuator according to claim 1, characterized in that, the movable body has the magnet inserted through the shaft portion with the gap therebetween, continuously provided in the vibration direction, and disposed at a radial inner side of the coil of the fixed body, a center yoke portion, and a balance weight portion, the center yoke portion is located at a position opposed to a central portion of the inner peripheral surface of the coil in the vibration direction during non-vibration of the movable body.

4. The vibration actuator according to claim 1, characterized in that, the movable body has the magnet and the fixed body has the coil, the shaft portion of the fixed body is made of a non-magnetic material.

5. The vibration actuator according to claim 1, characterized in that, contact members that contact the shaft portion due to an external impact are arranged on the inner peripheral surface of the through hole of the movable body so as to extend in the circumferential direction.

6. The vibration actuator according to claim 5, characterized in that, the contact members are made of resin or an elastic body.

7. The vibration actuator according to claim 1, characterized in that, the lengths of the plurality of leaf springs in the vibration direction between the fixed positions on the fixed body are different from the lengths of the plurality of leaf springs in the vibration direction between the fixed positions on the movable body.

8. The vibration actuator according to claim 7, characterized in that, The length of each of the plurality of leaf springs between the fixed positions on the movable body separated in the vibration direction is longer than the length of each of the plurality of leaf springs between the fixed positions on the fixed body separated in the vibration direction.

9. The vibration actuator according to claim 1, wherein: A magnetic fluid is disposed between the fixed body and the movable body.

10. The vibration actuator according to claim 9, wherein: The magnetic fluid is disposed between the shaft portion and the through hole, or between the outer diameter portion of the magnet and the inner diameter portion of the coil, or between both the shaft portion and the through hole and between the outer diameter portion of the magnet and the inner diameter portion of the coil.

11. The vibration actuator according to claim 1, wherein: The elastic support portion is fixed to the fixed body via a damping member that attenuates vibration.

12. An electronic device, wherein: The vibration actuator according to claim 1 is installed.

13. A vibration actuator, comprising: a movable body having one of a coil and a magnet disposed at a space from the coil on the radially inner side of the coil; a fixed body having the other of the coil and the magnet and having a shaft portion inserted through the movable body; and an elastic support portion that supports the movable body so as to be movable relative to the fixed body in such a manner that the movable body vibrates in the vibration direction by the cooperation of the energized coil and the magnet, The movable body has a through hole through which the shaft portion is inserted and a gap is formed between the through hole and the outer peripheral surface of the shaft portion, The elastic support portion is a plurality of leaf springs, and the plurality of leaf springs are arranged separately in the vibration direction so as to sandwich the center of gravity of the movable body and extend in a direction intersecting the vibration direction, At each end portion of the movable body in the vibration direction, an opening edge portion of the through hole is provided so as to project in a cylindrical shape in the vibration direction from a cylindrical protrusion, the inner peripheral portions of the plurality of leaf springs are externally fitted to the opening edge portion, and the leaf springs are joined orthogonally to the vibration direction with the shaft portion inserted through the inner peripheral portions, The plurality of leaf springs support the movable body so as not to contact the shaft portion when the movable body is not vibrating and when vibrating, A magnetic fluid is disposed between the fixed body and the movable body, The magnetic fluid is disposed between the shaft portion and the through hole, or between the outer diameter portion of the magnet and the inner diameter portion of the coil, or between both the shaft portion and the through hole and between the outer diameter portion of the magnet and the inner diameter portion of the coil.

14. An electronic device, wherein: The vibration actuator according to claim 13 is installed. ​

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