Vibration actuator

Abstract

Provided is a vibration actuator which facilitates the assembly work of a plate spring and a vibration control member and has excellent vibration properties. The vibration actuator has: a cylindrical case 2; a coil 3 provided in the case 2; a mover 4 which vibrates along a vibration axis line O of the case 2; a plate spring 5 having an inner peripheral section fixed to the mover 4; and a frame part 6 which fixes the plate spring 5 to the case 2. The frame part 6 is provided with a fixing part 61 provided to an outer peripheral section of the plate spring 5, and a vibration control part 62 provided to a vibrating portion of the plate spring 5.

Description

Technical Field

[0005] ,

[0001] The present invention relates to a vibration actuator, and more particularly to a vibration actuator in which a mover is supported by a leaf spring.

Background Art

[0002] Conventionally, in communication devices such as mobile phones, there is a notification method by vibration using a vibration actuator (or a vibration motor) as a method of notifying a person of an incoming call or an alarm. In recent years, in the fields of movies, games, and VR (Virtual Reality), for example, a vibration actuator is used as one of the production effects of action scenes or feedback means for players, and the reality is improved by stimulating the human sense of touch by vibration.

[0003] Some vibration actuators use a method of rotating an eccentric weight by a motor to generate vibration by inertial force. However, the method using a rotary motor has a drawback that since the vibration is generated by the inertial force of the eccentric weight, the reaction until the eccentric weight starts rotating and the vibration is obtained as a tactile sensation is slow, and the reality is impaired.

[0004] Therefore, as an actuator for obtaining a more realistic tactile sensation, for example, as shown in Patent Document 1, a voice coil type actuator may be adopted. In such a vibration actuator, a mover having a magnet is disposed in a cylindrical case, and a coil fixed to the case is disposed around the mover, and the mover is reciprocated in the case by energizing the coil. In that case, a disk-shaped leaf spring having a plurality of arm portions is used to support the mover so as to be reciprocable with respect to the case. Further, in the invention of Patent Document 1, a vibration control member for controlling the vibration characteristics is provided on the leaf spring.

Prior Art Documents

Patent Documents

[0005] [Patent Document 1] International Publication No. 2019-194223 [Disclosure of the Invention] [Problems that the invention aims to solve]

[0006] As described in Patent Document 1, when a vibration damping member is provided on a leaf spring, the vibration damping member is formed to conform to the shape of the leaf spring, and the vibration damping portion is attached to the leaf spring with adhesive or the like to prevent any misalignment between the leaf spring and the vibration damping member. In other words, if there is any misalignment in the shape and fixing of the leaf spring and the vibration damping member, the vibration damping member that protrudes from the arm portion of the leaf spring in a plane perpendicular to the vibration axis will act as a resistance and adversely affect the amplitude of the movable element. For this reason, the vibration damping member needs to be precisely formed to conform to the arm portion of the leaf spring, and at the same time, when fixing the vibration damping member to the leaf spring, accurate alignment of the leaf spring and the vibration damping member is necessary.

[0007] However, with conventional technology, the production cost of the vibration damping member is high because it is formed to conform to the shape of the arm portion of the leaf spring. In addition, the precise positioning and bonding of the leaf spring and the vibration damping member leads to a complicated assembly process.

[0008] Furthermore, in a vibration actuator in which a movable element is supported by a leaf spring, if the damping portion is fixed on the inner circumference of the leaf spring, the amplitude stress of the movable element concentrates on the damping member, which can lead to damage or detachment of the damping member and a deterioration in the acceleration performance and durability of the vibration actuator.

[0009] Furthermore, although the movable element is supported by the fixed case via a leaf spring, variations in the fixing positions of the case and the leaf spring, or the leaf spring and the damping member, will result in different positional relationships between the case, leaf spring, and movable element for each product, leading to non-uniform vibration characteristics of the leaf spring. In particular, if there is misalignment or looseness in the vibration axis direction of the case and leaf spring when the vibration axis of the movable element is used as a reference, the axial pressure applied to the leaf spring will become non-uniform, causing variations in the degree of deformation of the leaf spring. In addition, if there is misalignment in the circumferential fixing position of the leaf spring relative to the case, variations will occur in the contact position of the damping member with respect to the leaf spring, resulting in problems such as not being able to obtain appropriate vibration characteristics of the leaf spring despite the presence of a damping member.

[0010] This invention was proposed to solve the problems of the prior art described above. The object of this invention is to provide a vibration actuator that facilitates the assembly of leaf springs and vibration damping members and has excellent vibration characteristics. [Means for solving the problem]

[0011] The vibration actuator of the present invention has the following configuration. (1) Case. (2) A coil provided in the case. (3) A movable element that vibrates along the vibration axis of the case. (4) A leaf spring whose inner circumference is fixed to the movable element. (5) A frame portion for fixing the leaf spring to the case. (6) The frame portion is provided with a fixing portion on the outer circumference of the leaf spring and a vibration damping portion on the vibrating portion of the leaf spring.

[0012] In the present invention, the following configuration can be adopted. (1) The frame and the leaf spring are molded together. (2) The fixing portion is provided with an engaging portion that engages with the engaged portion on the case side. (3) The vibration damping portion is composed of a protrusion that extends inward from the inner diameter of the case, and a plurality of such protrusions are provided. (4) The leaf spring includes an annular inner peripheral portion to which the mover is attached, an outer peripheral portion attached to the vibration damping portion, and a plurality of spiral arms connecting the inner peripheral portion and the outer peripheral portion. (5) The vibration damping portion is integrally molded and fixed with the arm portion. (6) The arm portion has a through hole or a notch. (7) The vibration damping portion covers the leaf spring. (8) The frame portion includes the engaging portion where a part of the leaf spring is exposed, and the exposed portion of the leaf spring abuts against the axial positioning portion of the case. (9) The frame portion is subjected to knurling on the front surface and / or the back surface.

Advantages of the Invention

[0013] According to the present invention, the assembly work of the leaf spring and the vibration damping member is facilitated, and a vibration actuator having excellent vibration characteristics can be provided.

Brief Description of the Drawings

[0014] [Figure 1] It is a cross-sectional view taken along the vibration axis direction showing the overall configuration of the first embodiment. [Figure 2] It is an exploded perspective view showing the overall configuration of the first embodiment. [Figure 3] It is a perspective view of the inside of the cover case in the first embodiment. [Figure 4] It is an exploded perspective view of the case body and the yoke in the first embodiment. [Figure 5] It is an exploded perspective view of the coil and the bobbin in the first embodiment. [Figure 6] It is an exploded perspective view of the mover in the first embodiment. [Figure 7] It is an exploded perspective view of the leaf spring and the frame portion in the first embodiment. [Figure 8] It is a horizontal cross-sectional view and a vertical cross-sectional view of the leaf spring and the frame portion in the first embodiment. [Figure 9]It is an exploded perspective view showing a structure for fixing a leaf spring and a frame portion to a case body in the first embodiment. [Figure 10] It is an exploded perspective view showing a coil, a bobbin, and terminals arranged in a case body in the first embodiment. [Figure 11] It is an exploded perspective view showing the overall configuration of another embodiment of the present invention. [Figure 12] It is a horizontal sectional view and a longitudinal sectional view of a leaf spring and a frame portion showing another embodiment of the present invention. [Figure 13] It is a horizontal sectional view and a longitudinal sectional view of a leaf spring and a frame portion showing another embodiment of the present invention.

Mode for Carrying Out the Invention

[0015] [1. First Embodiment] [1-1. Configuration] Hereinafter, the vibration actuator 1 of the first embodiment will be described with reference to FIGS. 1 and 2. The vibration actuator 1 of the present embodiment is provided with members of the same shape with a symmetry plane (reference sign S in FIG. 1) orthogonal to the central axis at a position 1 / 2 in the direction of the vibration axis O as a boundary. Therefore, regarding the configuration of each member, only the configuration of one side of the symmetric shape will be described, and for the other side, the description will be omitted by attaching the same reference signs unless particularly necessary.

[0016] (1) Case and Coil The vibration actuator 1 mainly includes a cylindrical case 2 forming an outer shell, a coil 3 provided inside the case 2, a mover 4 that vibrates along the vibration axis O of the case 2, a leaf spring 5 whose inner peripheral portion is fixed to the mover 4, and a frame portion 6 that fixes the leaf spring 5 to the case 2.

[0017] Case 2 comprises a cylindrical case body 10 and a cover case 11 that closes the openings at both ends thereof. As shown in Figure 9, the end faces of the cylindrical case body 10 are provided with flange portions 102 that protrude radially inward from the case body 10. The flange portion 102 has a spiral inner edge with three stepped portions 102a, matching the shape of the leaf spring 5 which has spiral arms. Three locking claws 101 are provided on the surface of the flange portion 102 at 120-degree intervals, extending in the direction of the vibration axis O from the open end of the case body 10. The bases of the three locking claws 101 protrude inward from the edge of the opening of the case body 10 and serve as engaged portions for circumferential positioning of the frame portion 6.

[0018] As shown in Figure 9, the surface of the flange portion 102 is provided with an axial positioning portion 103 for the frame portion 6. In this embodiment, this positioning portion 103 protrudes from the surface of the flange portion 102 in close proximity to the locking claw 101. The surface of the positioning portion 103 is the part that abuts against the bottom surface of the leaf spring 5.

[0019] As shown in Figure 3, the cover case 11 is provided with three locking holes 111 on its outer circumference, and these engage with three locking claws 101 that protrude from the opening of the case body 10, thereby securing the two together.

[0020] In this embodiment, the case body 10 and the cover case 11 are each made of a resin material such as ABS, but are not limited to resin materials.

[0021] The coil 3 and the yoke 20 are inserted into case 2. As shown in Figure 4, the case body 10 has a cylindrical yoke 20 made of soft magnetic material that is formed to follow its inner circumference. The coil 3 is attached to the inner circumference of the yoke 20 in a state where it is electrically insulated from the yoke 20.

[0022] As shown in Figure 5, the coil 3 is wound along the outer recess of the bobbin 21 and positioned at a predetermined distance from the outer circumference of the movable element 4. To prevent contact between the movable element 4 and the coil 3 during vibration, the bobbin 21 has an inner wall on the inner circumference of the case body 10 so as to cover the surface of the coil 3 on the movable element 4 side, and a gap is provided between the inner wall of the bobbin 21 and the outer surface of the movable element 4. The coil 3 can generate a magnetic field by energizing from the terminal 106. The coil 3 may be temporarily fixed to the yoke 20 and bobbin 21 with adhesive or the like during assembly.

[0023] (2) Mover The movable element 4 is positioned inside the case body 10 so as to vibrate along the vibration axis O, which is the central axis of the cylindrical case 2. As shown in Figure 6, the movable element 4 has a disc-shaped magnet 30, a disc-shaped pole piece 31 positioned on the surface of the magnet 30, and a weight 32 positioned on the surface of the pole piece 31.

[0024] The magnet 30 is magnetized in the direction of the vibration axis O. The pole piece 31 is made of a soft magnetic material and is attached to the magnet 30 by the magnetic attraction force of the magnet 30 and adhesive. As shown in Figure 6, the pole piece 31 has a convex portion 311 in the center that is aligned with the vibration axis O, and the corresponding weight 32 has a recess 321 in the center that is aligned with the vibration axis O. The pole piece 31 and the weight 32 are integrated by the engagement of the convex portion 311 of the pole piece 31 and the recess 321 of the weight 32. Note that this integration does not require that the convex portion 311 of the pole piece 31 and the recess 321 of the weight 32 be engaged without any gaps; it also includes cases where there is a gap between them and they are loosely engaged, and the degree of engagement is not limited. The integration of the magnet 30, pole piece 31, and weight 32 is not limited to attachment by magnetic attraction force or adhesive, but may also be integrated by fixing them by mechanical means such as press-fitting or screwing, or by other means.

[0025] As shown in Figure 1, in the movable element 4, the outer diameter of the magnet 30 is smaller in the radial direction than the outer diameters of the pole piece 31 and the weight 32. In other words, the outer circumferences of the pole piece 31 and the weight 32 are located on the outermost side of the movable element 4 and are closest to the inner wall of the bobbin 21.

[0026] As shown in Figure 6, the weight 32 is made of a non-magnetic material and has a bell-shaped frustoconical portion 322 extending in the direction of the vibration axis O, and a disc-shaped base 323 that extends outward from the bottom surface of the frustoconical portion 322.

[0027] As shown in Figure 6, a central axis 324 is provided at the center of the tip of the frustoconical portion 322 of the weight 32, protruding in the direction of the vibration axis O. For example, the central axis 324 of the weight 32 is circular and is inserted into the shaft hole 50 of the leaf spring 5, fixing the leaf spring 5 and the weight 32 together.

[0028] (3) Leaf spring The leaf spring 5 is composed of one or more metal leaf springs; for example, in this embodiment, a processed thin sheet of stainless steel is used. The material of the leaf spring 5 is not limited to metal; it may also be a composite material containing resin or fiber. Furthermore, the material of the leaf spring 5 should preferably be one with excellent durability and flexibility.

[0029] As shown in Figure 7, a circular shaft hole 50 is provided at the center of the inner circumference of the leaf spring 5, into which the central shaft 324 of the weight 32 is fitted. The leaf spring 5 is connected to the weight 32 using this shaft hole 50. The central shaft 324 protruding from the surface of the leaf spring 5 is heated and pressurized by a jig and crushed, thereby crimping the surface of the weight 32 and the leaf spring 5 together. The means of fixing the leaf spring 5 and the weight 32 are not limited to crimping; as long as a circular central shaft 324 and a shaft hole 50 are provided, they can also be fixed (connected) by other methods such as screwing or adhesive.

[0030] As shown in Figure 7, the leaf spring 5 has an annular inner circumference 54 to which the movable element 4 is attached, an outer circumference 51 attached to the vibration damping section 62, and a plurality of spiral arms 52 connecting the inner circumference 54 and the outer circumference 51. Each arm 52 is provided at equal intervals of 120 degrees around the vibration axis O. The outer circumference 51 of each arm 52 is connected to a frame 6 that fixes the leaf spring 5 to the case body 10. Three through holes 53 are provided in the outer circumference 51.

[0031] (4) Frame As shown in Figures 7 to 9, the frame portion 6 is provided with a fixing portion 61 that secures the outer circumference 51 of the leaf spring 5 to the case 2, and a vibration damping portion 62 provided on the vibrating portion of the leaf spring 5. The fixing portion 61 is shaped to follow the inner circumference of the case body 10 and is substantially annular. A recess 611 is formed on the outer circumference of the fixing portion 61, which is recessed toward the inner circumference. As shown in Figure 9, this recess 611 engages with engaged portions provided on the bases of three locking claws 101 provided on the case body 10, forming an engaging portion that positions the frame portion 6 in the circumferential direction. The engaging portion and engaged portion are not limited to the shape of this embodiment as long as they engage with each other, and the number can be increased or decreased as needed.

[0032] On the inner circumference of the fixing portion 61, three stepped portions 61a are provided to match the shape of the leaf spring 5, which has spiral-shaped arms 52, similar to the flange portion 102 of the case body 10, and a part of the outer circumference 51 of the leaf spring 5 is exposed at the stepped portions 61a. This exposed portion of the leaf spring 5 corresponds to the "exposed portion" in the claim. More specifically, as shown in Figure 9, an exposed portion is provided in the recess 611 provided on the outer circumference of the frame portion 6, in which a part of the outer circumference 51 of the leaf spring 5 is exposed. This exposed portion provided in the recess 611 abuts against the axial positioning portion 103 provided on the case body 10.

[0033] As shown in Figures 7 to 9, the vibration damping section 62 that controls the vibration characteristics is composed of protrusions that extend inward beyond the inner diameter of the case body 10. The shape, placement, and number of the protrusions are not restricted as long as they protrude inward beyond the inner diameter of the case body 10. In this embodiment, multiple vibration damping sections 62 are provided at equal intervals, and three are provided, corresponding to the number of arms 52 of the leaf spring 5. The width and height of the vibration damping section 62 are formed in a region that provides mechanical resistance to the leaf spring 5 and allows for the acquisition of optimal vibration characteristics. The fixing section 61 and the vibration damping section 62 may be formed integrally by molding or as separate parts.

[0034] As shown in Figure 8, the frame portion 6 and the leaf spring 5 are integrated by molding. That is, by placing the leaf spring 5 in a mold and pouring resin into it, the frame portion 6 is overmolded on both the upper and lower surfaces of the leaf spring 5. As a result, the frame portion 6 and the leaf spring 5 are molded together as a single unit, with the leaf spring 5 sandwiched between the upper and lower parts of the frame portion 6.

[0035] The vibration damping section 62 is molded and fixed to the arm portion 52 of the leaf spring 5. The dimensions and shape of the vibration damping section 62, such as its thickness, the amount it protrudes from the frame portion 6, its circumferential length, and the number of sections, are set so that the leaf spring 5 exhibits the desired vibration characteristics. For example, the vibration damping section 62 may have an opening that reaches the surface of the leaf spring 5, or it may have an opening that penetrates the gap between the arm portions 52 of the leaf spring 5 and reaches from the surface to the back of the vibration damping section 62, or it may have multiple arm-shaped members protruding from the inner circumference of the frame portion 6 toward the center.

[0036] In this embodiment, the tip of the vibration damping part 62 fits into the groove between the arms 52 of the leaf spring 5, fixing it in place by clamping the front and back surfaces of the arms 52. However, the configuration is not necessarily limited to this, and it may also contact only one of the front or back surfaces of the leaf spring 5. When the vibration damping part 62 clamps the front and back surfaces of the arms 52, providing through holes 53 or notches in the arms 52 allows the resin constituting the vibration damping part 62 to flow smoothly from the front to the back surface of the arms 52, thereby improving the adhesion between the vibration damping part 62 and the leaf spring 5.

[0037] The frame portion 6 comprises at least one of polyethylene and elastomer. The elastomer is not limited to thermoplastic polyurethane elastomer (TPU). The elastic deformation of the frame portion 6, specifically the shear deformation of the polyethylene and the bending deformation of the elastomer, dampens the vibration of the leaf spring 5. The fixing portion 61 and the vibration damping portion 62 can be made of the same resin material, but the fixing portion 61 can be made of a hard resin with less elastic deformation, and the vibration damping portion 62 can be made of an elastic material such as elastomer. Furthermore, a reinforcing member made of metal or resin may be molded around the frame portion 6, separate from the leaf spring 5.

[0038] The leaf spring 5 configured in this way is elastically deformable within a predetermined range in the direction of the vibration axis O and in the intersecting direction including the radial direction S perpendicular to the vibration axis O. This predetermined range corresponds to the amplitude range of the movable element 4 when the vibration actuator 1 is used normally. Therefore, the predetermined range is a range in which the leaf spring 5 does not come into contact with the case 2 and does not exceed the limit of the elastic deformation of the leaf spring 5. Since the leaf spring 5 has three spiral arms 52, when the leaf spring 5 is deformed to its greatest extent, its cross-section forms a mountain shape with the center protruding the most in the direction of the vibration axis O, and the amount of deformation is less towards the fixing part between the leaf spring 5 and the frame 6, i.e., the outer circumference of the leaf spring 5. For this reason, even though the frame 6 and the flange portion 102 of the case body 10 have stepped portions 61a and 102a, respectively, and the shape of the inner circumference is spiral, when the leaf spring 5 deforms, it does not come into contact with the stepped portions 61a and 102a that protrude toward the center (vibration axis O) of the case 2.

[0039] (5) Terminal As shown in Figure 10, in this embodiment, terminals 211 for connecting the lead wires of each coil 3 are integrally fixed to the bobbin 21 by molding. On the other hand, a flat terminal fixing portion 105 is provided on the outer surface of the case body 10 in accordance with the position of the terminals 211, and a terminal 106 made of a printed circuit board is fixed to this fixing portion 105. The means for fixing the terminal 106 to the fixing portion 105 may be by molding the terminal 106 to the case body 10 or by ultrasonic welding. The terminal 106 is provided with a recess 107 for a connector into which the terminals 211 are fitted, and a power supply wire 108 for supplying power to the vibration actuator 1 is connected by means of soldering or other means. Note that the terminal 106 made of a printed circuit board is not necessarily required, and the terminals 211 for connecting the lead wires of each coil 3 and the power supply wire 108 may be directly connected.

[0040] [1-2. Operation of the Embodiment] (1) Operation of the vibration actuator 1 In the vibration actuator 1 configured as described above, when the coil 3 is not energized, the movable element 4 supported by the leaf spring 5 is located in the center in the direction of the vibration axis O, as shown in Figure 1.

[0041] When the movable element 4 is vibrated, alternating current is passed through the coil 3 via the terminal 106 in a direction that alternately generates magnetic fields of opposite polarity. That is, like polarity is generated in adjacent parts of the coil 3. For example, in the case of polarity, a thrust force is generated in the movable element 4 toward one side in the direction of the vibration axis O, and if the current flowing through the coil 3 is reversed, a thrust force is generated in the movable element 4 toward the other side in the direction of the vibration axis O. In this way, when alternating current is passed through the coil 3, the movable element 4 vibrates along the vibration axis O while receiving biasing forces from both sides by the leaf springs 5. The frame 6 dampens the vibration of the leaf springs 5 ​​through its elastic deformation, specifically the shear deformation of the polyethylene and the bending deformation of the elastomer.

[0042] The thrust generated in the movable element 4 is basically equivalent to the thrust given based on Fleming's left-hand rule. In this embodiment, since the two symmetrically arranged coils 3 are fixed to the case 2, a thrust is also generated in the movable element 4 to which the magnet 30 etc. is attached, as a reaction force to the force generated in the two coils 3.

[0043] (2) Assembly method In this embodiment, the vibration actuator 1 incorporates a bobbin 21 with a coil 3 mounted inside a case body 10 that integrates a yoke 20, and further inserts a movable element 4 inside the bobbin 21. In this case, a leaf spring 5 molded onto a frame 6 is fixed to the central axis 324 of the weight 32 of the movable element 4 by means of crimping or other means, and the movable element 4 fixed to the leaf spring 5 is inserted inside the bobbin 21.

[0044] The locking claw 101 of the case body 10 is fitted into the recess 611 of the frame portion 6, and the fixing portion 61 of the frame portion 6 is superimposed on the flange portion 102 of the case body 10, thereby fitting the frame portion 6 inside the case body 10. In this way, the recess 611 and the base of the locking claw 101 engage as an engaging portion and an engaged portion, respectively, and the frame portion 6 is positioned in the circumferential direction. At the same time, the leaf spring 5 exposed in the recess 611 comes into contact with the positioning portion 103 provided on the flange portion 102, and the leaf spring 5 is positioned in the axial direction.

[0045] Subsequently, the cover case 11 is placed over the opening of the case body 10 and pressed down, with the three locking claws 101 fitted into the three locking holes 111. The cover case 11 and the case body 10 are then fixed together by ultrasonic welding. In this case, by bringing the ultrasonic horn into contact with the outside of the cover case 11 and welding the three locking claws 101 or the entire circumference of the fixing portion 61 of the frame 6 with vibrational heat, airtightness between the frame 6 and the cover case 11, and between the frame 6 and the case body 10 can be ensured.

[0046] [1-3. Effects of the Embodiment] (1) In this embodiment, the vibration actuator 1 is equipped with a frame 6 that includes a leaf spring 5, a fixing part 61, and a vibration damping part 62. Therefore, it is not necessary to temporarily fix the leaf spring 5 to the case body 10, and the assembly of the three components to the case 2 can be carried out simply by fixing the frame 6 to the case body 10. Thus, the assembly work is simplified and work efficiency is improved.

[0047] (2) In this embodiment, the vibration actuator 1 is formed by molding the frame 6 and the leaf spring 5 together. Therefore, by simply setting the leaf spring 5 in a mold and molding it, the positioning of the leaf spring 5 relative to the frame 6 and the positioning of the vibration damping part 62 relative to the leaf spring 5 can be performed accurately and easily. Furthermore, it is possible to directly and firmly attach the vibration damping member to the leaf spring 5, preventing damage or peeling of the vibration damping member.

[0048] (3) In this embodiment, the vibration actuator 1 has a fixing portion 61 of the frame portion 6 formed toward the inner circumference, and a recess 611 is provided that engages with the base of the locking claw 101 of the case body 10. In this embodiment, since the frame portion 6 equipped with the vibration damping portion 62 and the leaf spring 5 are formed in advance, the engaged portion of the case body 10 and the recess 611 provided in the frame portion 6 engage with each other, thereby assembling the frame portion 6 equipped with the leaf spring 5 and vibration damping portion 62 to the case body 10 simultaneously. As a result, the positioning of the case body 10 and the frame portion 6 can be performed accurately and easily, and the assembly work can be made simpler.

[0049] (4) In this embodiment, the vibration actuator 1 has multiple vibration damping sections 62 that protrude inward from the inner diameter of the case body 10 and are provided at equal intervals. Therefore, by adjusting the width and height of the vibration damping sections 62, it is easy to adjust the vibration damping area to suit the size, weight, material, etc. of each component. In addition, by providing the vibration damping sections 62 at equal intervals, a stable vibration damping effect can be achieved.

[0050] (5) In this embodiment, the vibration actuator 1 has the vibration damping section 62 fixed to the outer circumference 51 of the leaf spring 5 by overmolding the resin of the frame section 6 onto the arm section 52 of the leaf spring 5. As a result, it is possible to obtain the mechanical resistance of the movable element 4 by utilizing the losses of the resin material, and the amplitude at the maximum acceleration frequency can be suppressed. In addition, the sharpness of the resonance peak can be suppressed, and the change in acceleration accompanying the change in resonance frequency can be suppressed. As a result, it is possible to prevent damage and peeling of the vibration damping member and improve the durability of the vibration actuator 1.

[0051] (6) In this embodiment, the vibration actuator 1 is provided with a recess 611 in the frame portion 6 in which a part of the leaf spring 5 is exposed, and the surface of the leaf spring 5 is in contact with the axial positioning portion 103 of the case body 10. Therefore, when axial positioning is performed, accurate positioning of the case body 10, the leaf spring 5 and the frame portion 6 is possible using the surface of the leaf spring 5 as a reference.

[0052] (7) In the vibration actuator 1 of this embodiment, the frame portion 6 is made of polyethylene and elastomer. Therefore, the leaf spring 5 is fixed to the case body 10 as the fixing portion 61 of the frame portion 6, and at the same time, vibration damping can be performed on the leaf spring 5 by shear deformation of the polyethylene and bending deformation of the elastomer in the vibration damping portion 62. Note that the frame portion 6 is not limited to being made of polyethylene and elastomer, and similar materials may be used.

[0053] (8) In this embodiment, by providing terminals 211 on the bobbin 21 for connecting the lead wires of each coil 3, the work of connecting the lead wires from the coils 3 to the terminal 106 becomes easier. In particular, in a small vibration actuator 1, the lead wires of the coils 3 are thin compared to the metal bars that make up the terminals 211 and require careful handling, and connection problems and disconnections are likely to occur, but by connecting the coils 3 and the terminal 106 via the terminals 211, such problems can be resolved.

[0054] [2. Other Embodiments] As described above, several embodiments of the present invention have been explained, but this is not intended to limit the scope of the invention. As listed below, it is possible to implement the invention in various other forms without departing from the spirit of the invention, and various omissions, substitutions, and modifications are permitted. These embodiments, combinations thereof, and variations thereof are included in the scope and spirit of the invention, as well as in the claims of the invention and its equivalents. The following are examples of embodiments included in the present invention.

[0055] (1) For example, in the above embodiment, the frame portion 6 and the leaf spring 5 are integrated by molding, but they may also be integrated by means of joining or fitting. Furthermore, the fixing portion 61 and the vibration damping portion 62 of the frame portion 6 are not limited to the same material, but may be made of different materials and then integrated. In addition, the upper and lower portions of the frame portion 6 that hold the leaf spring 5 may also be made of the same material or different materials.

[0056] (2) The engaging portion provided on the fixing portion 61 of the frame portion 6 and the engaged portion provided on the case body 10 do not matter as long as they engage and are fixed together, and it is not a concern which of them has a protrusion, recess or notch. In the illustrated embodiment, the recess 611 is used as both an engaging portion and an exposed portion of the leaf spring 5, but the engaging portion for positioning the leaf spring 5 and the frame portion 6 in the circumferential direction and the exposed portion of the leaf spring 5 for positioning in the axial direction may be provided at different locations.

[0057] (3) Instead of providing a locking claw 101 on the case body 10 and a locking hole 111 on the cover case 11, a locking hole may be provided on the case body 10 and a locking claw on the cover case 11.

[0058] (4) The leaf spring 5 has three arms 52 and three vibration damping parts 62, but the number is not limited to these.

[0059] (5) In the above embodiment, case 2 is cylindrical and the movable element 4 is substantially cylindrical, but the shapes of case 2 and movable element 4 are not limited to these, and may be polygonal or other shapes.

[0060] (6) In the above embodiment, the leaf spring 5 supporting the movable element 4 has spiral-shaped arms 52, but other leaf springs may be used. For example, irregular spiral, cross-shaped, or swastika-shaped leaf springs that combine straight lines as well as curves may be used. In this case, it is desirable that the inner guide also be shaped to match the shape of the leaf spring.

[0061] (7) The central tip of the frustoconical portion 322 of the weight 32 is not limited to a central axis 324, but may have a central hole. The leaf spring 5 and the weight 32 may be fixed by inserting a pin from the opening side of the case body 10 into the central hole and the shaft hole 50 of the leaf spring 5. Also, if a central axis 324 is provided, it is not limited to a circle, but may have other polygons such as a triangle or a square.

[0062] (8) Figure 11 is an exploded perspective view showing the overall configuration of an embodiment in which the coil 3 is not provided with a bobbin 21. The coil 3 is fixed to the yoke 20 with adhesive or the like so as to be positioned at a predetermined distance from the outer circumference of the movable element 4. In this embodiment, since the coil 3 is not provided with a bobbin 21, a smaller design is possible.

[0063] (9) Figure 12 is a horizontal cross-sectional view and a vertical cross-sectional view of a leaf spring 5 and a frame 6 showing an embodiment in which the leaf spring 5 has through holes 53 in the inner circumference 54 of the leaf spring 5. In this embodiment, there are three substantially triangular through holes 53 with rounded corners along the shape of the inner circumference 54 of the arm 52. The shape, number, and location of the through holes 53 are not limited thereto. In this embodiment, by providing through holes 53 in the inner circumference 54, the margin of load stress in the radial direction (horizontal direction) of the leaf spring 5 can be increased. Therefore, in this embodiment, it is possible to prevent stress concentration areas from occurring in the leaf spring 5 and to exhibit a stable vibration damping effect. In addition, by providing through holes 53 in the inner circumference 54, the margin of load displacement in the amplitude direction (vertical direction) of the leaf spring 5 can be increased. Therefore, compared to the case in which there are no through holes 53 in the inner circumference 54, it becomes easier to reduce the rigidity of the leaf spring 5 itself, and a wide range of vibration output designs becomes possible.

[0064] (9) Figure 13 is a horizontal cross-sectional view and a vertical cross-sectional view of the leaf spring 5 and frame portion 6, showing an embodiment in which knurling is applied to the front and back surfaces of the frame portion 6. In this embodiment, the frictional force on the front and back surfaces of the frame portion 6 can be increased by knurling. Therefore, compared to the case where knurling is not applied, when the frame portion 6 is fixed to the case body 10 and the cover case 11, it is possible to prevent them from slipping and to make them less likely to come off. In Figure 13, the knurling shows a mesh-like pattern of bumps and grooves, but it is not limited to this, and the knurling may also be applied to bumps with many alternating peaks and valleys, or bumps with many small protrusions. Instead of knurling, textured processing or blast processing may also be used. Furthermore, knurling may be applied to only one of the front or back surfaces of the frame portion 6, or knurling may be applied to the outer circumference of the fixing portion 61 of the frame portion 6. [Explanation of Symbols]

[0065] 1. Vibration actuator 2 cases 3 coils 4 Mover 5. Leaf spring 6 Frame section 10 Case body 101 Locking claw 102 Flange section 102a Stepped section 103 Positioning section 105 Terminal fixing part Terminal 106 11 Cover Cases 111 Section Drill 20 York 21 bobbins 211 terminals 30 Magnets 31 pole pieces 311 Convex part 32 weight 321 Recess 322 Truncated cone section 323 Bottom 324 Center axis 50 shaft hole 51 Outer periphery 52 Arm 53 Through hole 54 Inner circumference 61 Fixed part 61a Stepped section 611 recess 62 Vibration damping section

Claims

1. The case and, A coil provided in the aforementioned case, A movable element that vibrates along the vibration axis of the case, A leaf spring having an inner circumference fixed to the movable element, an outer circumference fixed to the case side, and a plurality of arms provided between the inner circumference and the outer circumference, A frame portion for fixing the leaf spring to the case, It has, The aforementioned frame portion is A fixing part fixed to the outer circumference of the leaf spring, A vibration actuator characterized by having multiple vibration damping parts provided integrally with the vibrating portion of the arm.

2. The vibration actuator according to claim 1, wherein the frame portion and the leaf spring are molded.

3. The vibration actuator according to claim 1 or claim 2, wherein the fixing portion is provided with an engaging portion that engages with the engaged portion on the case side.

4. The vibration damping portion is composed of a protrusion that extends inward beyond the inner diameter of the case. The vibration actuator according to any one of claims 1 to 3, wherein a plurality of the aforementioned protrusions are provided.

5. The vibration actuator according to claims 1 to 4, wherein the vibration damping portion is molded and fixed to the arm portion.

6. The vibration actuator according to claim 1 to claim 5, wherein the arm portion has a through hole or notch.

7. The vibration damping portion covers the leaf spring, as described in any one of claims 1 to 6.

8. The vibration actuator according to claim 3, wherein the frame portion includes the engagement portion in which a part of the leaf spring is exposed, and the exposed portion of the leaf spring abuts against the axial positioning portion of the case.

9. The vibration actuator according to any one of claims 1 to 8, wherein the frame portion is knurled on its surface and / or back surface.

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