Vibration type actuator and electronic device

Abstract

An oscillating actuator includes: an oscillator including an electro-mechanical energy conversion element and an elastic member; and a contact member in contact with the elastic member, vibration of the vibrator allowing relative movement of the contact member and the vibrator in the first direction. The elastic member includes a rectangular plate portion in a first direction, a protruding portion protruding in a second direction intersecting the first direction, and an extending portion extending from the plate portion in a direction in the first direction. The vibration type actuator further includes a support member in contact with at least one of the extension portion and the plate portion to movably support the vibrator in the second direction. A portion of the elastic member is provided with a contact surface that contacts the support member in the second direction, and an inclined portion that adjoins the contact surface and is inclined in a direction away from the support member with respect to the contact surface.

Description

Technical Field

[0001] The invention relates to a vibration actuator and an electronic device. Background Art

[0002] Various configurations of vibration actuators using electro-mechanical energy conversion elements are known. For example, a vibration actuator is known that drives a vibrator having the following configuration: the electro-mechanical energy conversion element is coupled to an elastic member (hereinafter referred to as a vibration plate) having two protrusions by bringing the vibrator into pressure contact with a driven member.

[0003] The vibration actuator applies a predetermined AC voltage to the electromechanical energy conversion element, thereby generating an elliptical motion or a circular motion at the leading edge of the two protrusions in a plane including a direction connecting the two protrusions and a protruding direction of the protrusions. When this structure is used, when the driven member receives a friction driving force from the two protrusions, the vibrator and the driven member can move relative to each other in the direction connecting the two protrusions.

[0004] The vibration actuator discussed in Patent Document 1 has the following structure: the end surface of the rectangular portion and the end surface of the extension portion of the vibration plate are in contact with and loosely fit with a plurality of protrusions provided on the support member, thereby holding the vibrator. When this structure is used, it is possible to reduce the size of the motor driving direction and reduce the risk of generating abnormal sound.

[0005] In addition, the vibration actuator discussed in Patent Document 2 focuses on the method of combining a vibration plate with an electro-mechanical energy conversion element and is designed to shorten the processing time of the polishing process and improve the shape accuracy of the vibration plate after polishing by defining the direction of burrs generated during molding.

[0006] Meanwhile, there has recently been a demand for applying the vibration actuator to various occasions, and there has been a problem of further enhancing the stability of the driving speed of the vibration actuator itself.

[0007] Reference List

[0008] Patent Literature

[0009] PTL 1: Japanese Patent Application Laid-Open No. 2020-198658

[0010] PTL 2: Japanese Patent Application Laid-Open No. 2015-43670 Summary of the invention

[0011] Technical issues

[0012] The present invention has been made to solve the above-mentioned problems, and aims to provide a vibration actuator capable of performing a driving operation at a stable speed.

[0013] Problem Solution

[0014] In order to solve the above problems, a vibration actuator according to the present invention includes: a vibrator, the vibrator including an electro-mechanical energy conversion element and an elastic member; and a contact member, the contact member is in contact with the elastic member, and the vibration of the vibrator allows the contact member and the vibrator to move relative to each other in a first direction, wherein the elastic member includes a rectangular plate portion along the first direction, a protrusion protruding in a second direction intersecting the first direction, and an extension portion extending from the plate portion in a direction along the first direction, wherein the vibration actuator also includes a supporting member, the supporting member is in contact with at least one of the extension portion and the plate portion to support the vibrator movably along the second direction, and wherein a portion of the elastic member is provided with a contact surface and an inclined portion, the contact surface is in contact with the supporting member along the second direction, and the inclined portion is adjacent to the contact surface and inclined relative to the contact surface in a direction away from the supporting member.

[0015] Advantageous Effects of the Invention

[0016] According to the present invention, it is possible to provide a small-sized vibration actuator capable of performing a driving operation at a stable speed. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] [ Figure 1 ] Figure 1 is an assembled perspective view of a vibration actuator according to a first exemplary embodiment of the present invention.

[0018] [ Figure 2 ] Figure 2 is an exploded perspective view of a vibration actuator according to a first exemplary embodiment of the present invention.

[0019] [ Figure 3A ] Figure 3A A vibration mode according to a first exemplary embodiment of the present invention is illustrated.

[0020] [ Figure 3B ] Figure 3B A vibration mode according to a first exemplary embodiment of the present invention is illustrated.

[0021] [ Figure 4 ] Figure 4 is a combined perspective view illustrating a vibrator and a supporting member according to a first exemplary embodiment of the present invention.

[0022] [ Figure 5A ] Figure 5A is a combined plan view illustrating a vibrator and a supporting member according to a first exemplary embodiment of the present invention.

[0023] [ Figure 5B ] Figure 5B is a combined plan view illustrating a vibrator and a supporting member according to a first exemplary embodiment of the present invention.

[0024] [ Figure 6 ] Figure 6 is a combined plan view of a vibrator and a piezoelectric element bonding / positioning assembly according to a first exemplary embodiment of the present invention.

[0025] [ Fig. 7A ] Fig. 7A is a cross-sectional view illustrating a side surface of a supporting member contacting an elastic member according to a first exemplary embodiment of the present invention.

[0026] [ Figure 7B ] Figure 7B is a cross-sectional view illustrating a side surface of a supporting member contacting an elastic member according to a first exemplary embodiment of the present invention.

[0027] [ Figure 8 ] Figure 8 is a cross-sectional view illustrating a side surface of a supporting member contacting an elastic member according to a second exemplary embodiment of the present invention.

[0028] [ Fig. 9 ] Fig. 9 is an exploded perspective view of a vibration actuator according to a third exemplary embodiment of the present invention.

[0029] [ Fig.10 ] Fig.10 is a cross-sectional view of a vibration actuator according to a third exemplary embodiment of the present invention.

[0030] [ Fig.11A ] Fig.11A is a top view illustrating a schematic configuration of an image capture device including a vibration-type actuator according to an exemplary embodiment of the present invention.

[0031] [ Fig. 11B ] Fig. 11B is a block diagram illustrating a schematic configuration of an image capturing apparatus including a vibration-type actuator according to an exemplary embodiment of the present invention.

[0032] [ Fig. 12A ] Fig. 12A A top dead center state of a shearing process in press molding according to a fifth exemplary embodiment of the present invention is illustrated.

[0033] [ Fig. 12B ] Fig. 12B A bottom dead center state of a shearing process in press molding according to a fifth exemplary embodiment of the present invention is illustrated.

[0034] [ Fig. 12C] Fig. 12C An enlarged view of a sheared portion subjected to a shearing process in press molding according to a fifth exemplary embodiment of the present invention is illustrated.

[0035] [ Fig.13A ] Fig.13A is a top view illustrating a trimming process of an elastic member according to a fifth exemplary embodiment of the present invention.

[0036] [ Fig. 13B ] Fig. 13B is an enlarged top view of an extending portion during a trimming process of an elastic member according to a fifth exemplary embodiment of the present invention.

[0037] [ Fig.14 ] Fig.14 is a side view illustrating an end surface shape of an elastic member according to a fifth exemplary embodiment of the present invention.

[0038] [ Fig.15A ] Fig.15A is an enlarged view illustrating a burr state in a contact portion between an elastic member and a supporting member according to a fifth exemplary embodiment of the present invention.

[0039] [ Fig. 15B ] Fig. 15B is an enlarged view illustrating a state of a crushed burr in a contact portion between an elastic member and a supporting member according to a fifth exemplary embodiment of the present invention.

[0040] [ Fig.16A ] Fig.16A A top dead center state of a burr crushing process in press molding according to a fifth exemplary embodiment of the present invention is illustrated.

[0041] [ Fig. 16B ] Fig. 16B A midway state of burr crushing processing in press molding according to a fifth exemplary embodiment of the present invention is illustrated.

[0042] [ Fig. 16C ] Fig. 16C A bottom dead center state of a burr crushing process in press molding according to a fifth exemplary embodiment of the present invention is illustrated.

[0043] [ Fig.17 ] Fig.17 is an enlarged view illustrating an inclined surface of an elastic member according to a fifth exemplary embodiment of the present invention.

[0044] [ Fig.18A ] Fig.18A is an enlarged view illustrating secondary shearing of a contact surface between an elastic member and a supporting member according to a fifth exemplary embodiment of the present invention.

[0045] [ Fig.18B ] Fig.18B is an enlarged view of an inclined surface of a contact surface between an elastic member and a supporting member according to a fifth exemplary embodiment of the present invention. DETAILED DESCRIPTION

[0046] The vibration actuator according to the present invention for solving the above-mentioned problem comprises a vibrator and a contact member, wherein the vibrator comprises an electromechanical energy conversion element and an elastic member, and the contact member contacts the elastic member. In the vibration actuator, the vibration of the vibrator allows the contact member to move relative to the vibrator in a first direction.

[0047] The elastic member includes a rectangular plate portion along a first direction, a protruding portion protruding in a second direction intersecting the first direction, and an extending portion extending from the plate portion in a direction along the first direction.

[0048] The vibration actuator further includes a supporting member, the supporting member contacts at least one of the extension portion and the plate portion to movably support the vibrator in the second direction. A portion of the elastic member is provided with a contact surface and an inclined portion, the contact surface contacts the supporting member in the second direction, and the inclined portion is adjacent to the contact surface and inclined relative to the contact surface in a direction away from the supporting member.

[0049] The end surface of the elastic member is provided with a vertical surface and an inclined surface, which reduces the possibility and degree of interference with the support member by burrs of the elastic member that are flattened during processing or protruded due to the driving of the actuator.

[0050] It is also expected that even if the burr of the elastic member is flattened during processing, the leading edge of the extension for positioning during the process of bonding the electro-mechanical energy conversion element to the elastic element can be prevented from interfering with the elastic member positioning jig.

[0051] Examples of the vibration actuator may include a vibration actuator in which a common contact member is linearly driven by a plurality of vibrators and a vibration actuator in which a common contact member is rotationally driven by a plurality of vibrators located on a circumference.

[0052] In the support structure of the vibrator, the friction resistance caused by the interference between the support member and the vibration plate can be reduced by forming the edge of the vibration plate in an appropriate shape and changing the contact condition between the support member and the vibration plate, and the driving speed can be further stabilized. Exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0053] First Exemplary Embodiment

[0054] The first exemplary embodiment is an example in which the present invention is applied to a linear vibration type actuator that performs a linear driving operation. Figures 1 to 7BDetails of a linear vibration actuator are shown. Figure 1 is an assembled perspective view of a vibration actuator 1 according to a first exemplary embodiment of the present invention. Figure 2 : is an exploded perspective view of the vibration actuator 1. The moving direction of the slider 9 serving as the contact member is defined as the X direction, the pressing direction is defined as the Z direction, and the direction perpendicular to the Z direction is defined as the Y direction.

[0055] The term "contact member" refers to a member that contacts the vibration body and moves relative to the vibration body due to the vibration generated in the vibration body. The contact between the contact member and the vibration body is not limited to direct contact without any other member interposed between the contact member and the vibration body. The contact between the contact member and the vibration body may be an indirect contact with any other member interposed between the contact member and the vibration body, as long as the contact member can move relative to the vibration body due to the vibration generated in the vibration body. The term "any other member" is not limited to members independent of the contact member and the vibration body (for example, a high friction member made of a sintered body). The term "any other member" may include a surface treatment portion formed on the contact member or the vibration body by plating, nitriding, etc.

[0056] The elastic member 3 and the piezoelectric element 4 serving as an electro-mechanical energy conversion element are fixed with an adhesive or the like. Furthermore, a flexible printed circuit board 5 is fixed to the piezoelectric element 4 on the opposite surface of the elastic member 3. These components constitute the vibrator 2. The flexible printed circuit board 5 is fixed with an anisotropic conductive glue or an anisotropic conductive film so that electricity can be passed only in the Z direction.

[0057] The elastic member is composed of a roughly rectangular plate portion, one or more protrusions protruding from the plate portion toward the outside of a flat surface forming the plate portion (i.e., protruding in a direction intersecting the moving direction), and one or more extensions extending from the plate portion in a direction along the flat surface (i.e., along the moving direction).

[0058] The moving direction is defined as a first direction, and a direction intersecting the moving direction is defined as a second direction.

[0059] The elastic member 3 is preferably made of a material that causes less vibration attenuation (such as metal or ceramic). During the manufacturing process of the elastic member 3, the protrusion 3a can be integrally formed by die-forming, cutting, etc., or the protrusion 3a can be manufactured separately and then fixed by welding, bonding, etc. A plurality of protrusions 3a can be provided as in the present exemplary embodiment, or one protrusion 3a can be provided.

[0060] For example, lead zirconate titanate is used for the piezoelectric element 4. Alternatively, a material mainly containing a lead-free piezoelectric material such as barium titanate or sodium bismuth titanate may be used. The lead-free material refers to a material having a lead content of 1000 ppm or less. Electrode patterns (not shown) are formed on both surfaces of the piezoelectric element 4, and power is supplied from a flexible printed circuit board 5. A support member 6 serving as a support member for supporting the vibrator 2, a pressurizing spring 7, and a base 8 receiving pressure from the pressurizing spring 7 are provided.

[0061] As a specific structure, Figure 1 As shown in FIG. 1 , a support member 6 for pressurizing and supporting the vibrator 2 is provided below the vibrator 2. A pressurizing spring 7 applies pressure to the support member in the Z direction, and a base 8 serving as a pressure receiving member receives the reaction force. As the pressurizing spring 7, a conical coil spring is used to reduce the size of the vibration actuator 1 in the Z direction. The coil shape is illustrated in a simplified manner.

[0062] The slider 9 serving as a contact member is disposed above the vibrator 2 and contacts the protrusion 3a of the elastic member 3. The slider 9 is fixed to the slider holder 10 and the slider 9 and the slider holder 10 are integrally driven in the X direction relative to the vibrator 2. Rubber for reducing vibration may be provided between the slider 9 and the slider holder 10. The slider 9 is made of metal, ceramic, resin or a composite material thereof having high wear resistance. Specifically, a nitride stainless steel material such as SUS420J2 is excellent in wear resistance and mass productivity.

[0063] Three balls 11 are sandwiched between a slider holder 10 having three pairs of upper and lower rails and a ball rail 12, and the ball rail 12 is fixed to the base 8, thereby allowing the slider 9 and the slider holder 10 to move in the X direction relative to other components. The slider holder 10 is provided with a power transmission portion having a desired shape, thereby transmitting power to the outside. Although the present exemplary embodiment illustrates an example in which the vibrator 2 is fixed and the slider 9 is configured to be movable, the slider 9 may be fixed and the vibrator 2 may be configured to be movable.

[0064] Next, we will refer to Figure 3A and Figure 3B Described is the vibration mode excited in vibrator 2. In the present exemplary embodiment, an AC voltage is applied to piezoelectric element 4 through flexible printed circuit board 5 to excite two different out-of-plane bending vibrations in vibrator 2, thereby generating vibrations obtained by combining the two different out-of-plane bending vibrations.

[0065] Mode A corresponding to the first vibration mode is a primary out-of-plane bending vibration mode in which two nodes appear parallel to the X direction which is the longitudinal direction of the vibrator 2. The vibration in mode A allows the protrusions 3a located at two locations to be displaced in the Z direction which is the pressurizing direction. Mode B corresponding to the second vibration mode is a secondary out-of-plane bending vibration mode in which three nodes appear approximately parallel to the Y direction which is the lateral direction of the vibrator 2. The vibration in mode B allows the protrusions 3a located at two locations to be displaced in the X direction.

[0066] The combination of vibrations in mode A and mode B allows the protrusions 3a located at two positions to generate elliptical motion or circular motion in the ZX plane. When the slider 9 is in pressure contact with these protrusions 3a, a friction force is generated in the X direction and a driving force (thrust) that moves the vibrator 2 and the slider 9 relative to each other is generated. In the present exemplary embodiment, the vibrator 2 is held by the method described below so that the slider 9 moves in the X direction.

[0067] In order to effectively drive the vibration actuator 1, it may be necessary to support the vibrator 2 without suppressing the vibration (displacement) in the two vibration modes excited in the vibrator 2. To achieve this, it may be necessary to support the portion near the node in the two vibration modes. In view of this, the support member 6 may be as follows: Figure 2 As shown in FIG. 2 , two protrusions 6 a are provided to selectively pressurize and hold a node common to two vibration modes excited in the vibrator 2 . Figure 3A and Figure 3B The contact position and node position in each vibration mode are shown. Six positions where the nodes in the two vibration modes overlap each other appear. When the two longitudinal center portions are pressurized, an equalization function around the Y axis can be provided, and the vibrator 2 and the slider 9 can be brought into contact with each other approximately uniformly.

[0068] Figure 4 is an enlarged perspective view illustrating a vibrator and a supporting member. Figure 5A and Figure 5B 6 is a plan view of the vibrator and the support member. The support member 6 is provided with four loose fitting portions 62. In each loose fitting portion 62, the columnar portion 6b is loosely fitted to a corresponding one of the four corners of the elastic member, thereby supporting the elastic member. Each corner serving as a support portion does not necessarily include the vertex of a corresponding one of the four corners of the elastic member.

[0069] The support member 6 supports (loosely fits) the elastic member in a state where the support member 6 has a gap in at least one of the X direction and the Y direction relative to the peripheral portion when viewed from the projection on the XY-plane formed by the rectangular plate portion and the extension portion in the vibrator 2. These loose fitting portions 62 function as stoppers when positioning is performed during the assembly process of the vibrator 2 or when some external force acts on the slider 9.

[0070] Figure 5A The diagram shows a state in which the vibrator is located at the center and all the extending portions 32 have gaps with respect to the four columnar portions 6 b of the supporting member 6 . Figure 5B The diagram shows a state where the extension 32 is brought into contact with one side by an external force (as indicated by an arrow). When the elastic member 3 is formed by a press process, burrs or sagging often occur at the edge of the outer shape due to the punching process. Fig. 7A and Figure 7B The diagram shows an XZ cross-sectional shape as a state of a contact surface and an inclined portion between a support member 6 (not shown) and an elastic member 3. The elastic member 3 is provided with a substantially rectangular plate portion 30 and a total of four extension portions 32, including two extension portions 32 extending from the plate portion 30 in the positive direction of the X direction and two extension portions 32 extending from the plate portion 30 in the negative direction of the X direction.

[0071] In the present exemplary embodiment, when the pressing surface (XY plane portion in the elastic member 3) is in contact with the supporting member such as Figure 5B When the piezoelectric element is in contact with each other as shown in FIG. 1 , it may be necessary to reduce the friction resistance caused by interference or prevent the friction resistance from occurring. For example, if the burr included in the elastic member 3 is flattened and protrudes along the XY plane, and the protruding burr enters the columnar portion 6 b of the support member, the feeding vibration is suppressed and the motor performance is deteriorated. In addition, when the piezoelectric element is bonded to the elastic member and as shown in FIG. Figure 6 When positioning is performed by combining the jig 13 as shown in FIG. 1 , it may be necessary to prevent the tip end surface 31 b of each extension portion 32 from interfering with the jig due to protruding burrs.

[0072] Fig. 7A The diagram shows a state in which the punching burr 3D protrudes downward in the Z direction on the XZ cross section of the elastic member 3. This exemplary embodiment has the following features: Fig. 7A As shown in FIG. 1 , below the shear surface 3A which is the contact surface of the support member (not shown), a fracture surface 3C which is moderately inclined relative to the shear surface 3A is provided in a direction away from the support member (not shown). Providing the fracture surface 3C as described above reduces the possibility that the burr 3D is deformed even after the bottom surface of the elastic member 3 is polished, etc. and the burr 3D′ of the elastic member 3 is formed. Figure 7B The possibility of causing the burr to protrude from the shearing surface 3A when protruding to the left as shown in FIG.

[0073] It may be necessary to prevent the burr 3D' that is flattened after another process from protruding toward the left side of the shear surface 3A, or to minimize the amount of protrusion. Therefore, the fracture surface 3C below the shear surface A may desirably have a moderate inclination. The adjustment of this inclination is based on the amount of clearance between the die and the punch. The inclination increases as the amount of clearance increases. At the same time, the sag 3B also increases. If each extension 32 has a large sag 3B, there is no problem. However, if the rectangular portion used to bond the piezoelectric element has such a large sag, the sag may still exist even after the bonding surface is polished, which may have an adverse effect on the bonding strength. In view of this, it may be necessary to reduce the sag 3B at the ridge of the bonding surface and prevent the burr 3D' from protruding from the shear surface 3A. Since the tip surface 31b of each extension 32 is not a bonding surface, the inclination of the cross section can be increased by increasing the amount of clearance. Figure 5B In the portion indicated by the middle arrow, the gap amount increases only at the extension 32, which causes the punching process to be unbalanced. Therefore, the gap amount is determined in consideration of the sag 3B at the ridge of the bonding surface.

[0074] As described above, according to the present invention, a compact vibration actuator capable of stable driving operation can be provided with a smaller number of components than in the related art.

[0075] In the linear vibration actuator according to the present invention, the method of generating elliptical motion or circular motion on the contact surface is not limited to the above method. For example, vibrations in a bending vibration mode different from the above vibration modes may be combined. Alternatively, vibrations in a longitudinal vibration mode in which the elastic member is stretched in the longitudinal direction may be combined with vibrations in a bending vibration mode.

[0076] Any driving method may be used as long as the method is capable of generating elliptical motion and circular motion on the contact surface by combining a vibration mode in which the contact surface is displaced in the movement direction of the driven member with a vibration mode in which the contact surface is displaced in the pressing direction and the vibration mode includes a common node for pressing and holding.

[0077] In addition, a structure in which a slider is sandwiched between two vibrators to increase the thrust can be adopted.

[0078] Second Exemplary Embodiment

[0079] Will refer to Figure 8 A second exemplary embodiment is described. Figure 8 The elastic member shown in includes a plurality of inclined portions having different inclination angles or different curvatures as the inclined portions as described above, the plurality of inclined portions being inclined in a direction away from the supporting member and being adjacent to each other.

[0080] As Figure 8In the example of the manufacturing method of the elastic member shown in, according to the first exemplary embodiment of the present invention, a burr flattening process is added to the stamping process of the elastic member 3 in the vibration actuator. The side surface formed after the burr flattening process has a cross-sectional shape in which an inclined surface 3E is formed due to the flattening of the burr 3D. In other words, a first inclined surface 3C and a second inclined surface 3E are formed. The burr flattening process causes the burr 3D to plastically flow toward the shear surface 3C. However, sharp burrs can be eliminated, and adverse effects on motor performance can be further avoided.

[0081] Similarly, you can use settings such as Figure 8 The structure of the hanging portion formed by the hanging portion 3B shown in FIG. 1 and further providing another hanging portion adjacent to the contact surface on the opposite side of the inclined portion with respect to the contact surface.

[0082] In this case, it may be necessary to adopt a configuration in which the electro-mechanical energy conversion element is provided on the surface of the plate portion of the elastic member on the side closer to the drooping portion than the inclined portion.

[0083] Third Exemplary Embodiment

[0084] Will refer to Fig. 9 and Fig.10 A third exemplary embodiment is described. Fig. 9 : is an exploded perspective view of a vibration actuator according to a third exemplary embodiment of the present invention. A radial direction is defined as an X direction, a rotation direction is defined as a θ direction, and a pressurizing direction is defined as a Z direction. Fig.10 is a ZX cross-sectional view of a vibration actuator according to a third exemplary embodiment of the present invention.

[0085] The present exemplary embodiment has a feature that three vibrators 202 (202-1, 202-2, 202-3) are held by an annular base 206. The configuration and driving principle of each vibrator 202 are similar to those of the first exemplary embodiment or the second exemplary embodiment, and thus description thereof will be omitted.

[0086] Three sets of protrusions and loose fitting portions having functions similar to those of the first exemplary embodiment or the second exemplary embodiment are provided on the annular base 206 at intervals of 120 degrees, and respectively hold and loosely fit the vibrator 202. The flexible printed circuit boards of the vibrator 202 are connected through a connected flexible printed circuit board (not shown), and the same driving voltage is applied to each piezoelectric element.

[0087] The rotor 211 serving as a driven member contacts the protrusion of each vibrator 202 and rotates by the driving force generated in the tangential direction. The upper portion of the rotor 211 is provided with an anti-vibration rubber 212, and each component is held in a state of being able to rotate integrally with the power transmission member 216.

[0088] On the other hand, the annular base 206 having an annular shape is combined with the inner cylinder 217 at a portion not shown, thereby regulating movement in the central axis direction and radial directions and rotation around the central axis.

[0089] A pressure auxiliary member 207 having a predetermined rigidity is provided at the lower portion of the annular base 206 to make the pressure generated by the wave washer 208 as a supporting member uniform. A pressure receiving member 209 is located below the wave washer 208.

[0090] The pressure receiving member 209 is engaged with the inner cylinder 217 on its inner diameter side by a screw or a bayonet structure. The vibration actuator 201 rotates the pressure receiving member 209 to move in the central axis direction, thereby compressing the wave washer 208. The components ranging from the annular base 206 to the power transmission member 216 are pressurized and sandwiched between the outer cylinder 213, the inner cylinder 217 and the pressure receiving member 209. The ball 214 and the retainer 215 are provided between the outer cylinder 213, the inner cylinder 217 and the power transmission member 216, and rotatably support the power transmission member 216 while receiving pressure. The outer cylinder 213 and the inner cylinder 217 are connected together by tightening the cap 210.

[0091] Furthermore, in the present exemplary embodiment, the protrusion and the loose fitting portion on the annular base 206 provide a balancing function about the X-axis, thereby simplifying the structure for supporting the vibrator 202 .

[0092] Although the present exemplary embodiment described above illustrates an example in which three vibrators 202 are provided, the present exemplary embodiment is not limited to this example. Any number of vibrators 202 may be provided as long as at least one vibrator 202 can be provided on the annular base 6 .

[0093] Fourth Exemplary Embodiment

[0094] The present invention may provide an electronic device including any one of the above-mentioned vibration actuators and a member driven by the vibration actuator.

[0095] The vibration actuator can be used, for example, to drive a lens of an image pickup device (optical device). Specifically, an optical device including a vibration actuator and an optical element driven by the vibration actuator can be provided.

[0096] Therefore, for example, an image capturing apparatus that drives a lens as an optical element within a lens barrel using the rotary vibration type actuator according to the third exemplary embodiment will be described.

[0097] Fig.11A7 is a top view illustrating a schematic configuration of an image capture device 700. The image capture device 700 includes a camera body 730, and the camera body 730 includes an image sensor 710 and a power button 720. The image capture device 700 also includes a lens barrel 740, and the lens barrel 740 includes a first lens group (not shown), a second lens group 320, a third lens group (not shown), a fourth lens group 340, and vibration-type drive devices 620 and 640. The lens barrel 740 can be replaced with an interchangeable lens. The lens barrel 740 suitable for an image capture target can be attached to the camera body 730. In the image capture device 700, two vibration-type drive devices 620 and 640 drive the second lens group 320 and the fourth lens group 340, respectively.

[0098] Although the detailed structure of the vibration type driving device 620 is not shown, the vibration type driving device 620 includes a vibration type actuator and a driving circuit for the vibration type actuator. The rotor 211 is located in the lens barrel 740 so that the radial direction is roughly orthogonal to the optical axis. In the vibration type driving device 620, the rotor 211 rotates around the optical axis, and the rotation output of the driven member is converted into a translational motion in the optical axis direction via gears etc. (not shown), so that the second lens group 320 moves in the optical axis direction. The vibration type driving device 640 has a structure similar to the vibration type driving device 620, so that the fourth lens group 340 moves in the optical axis direction.

[0099] Fig. 11B 7 is a block diagram illustrating a schematic configuration of an image capturing device 700. A first lens group 310, a second lens group 320, a third lens group 330, a fourth lens group 340, and a light amount adjustment unit 350 are located at predetermined positions on the optical axis within a lens barrel 740. Light passing through the first lens group 310 to the fourth lens group 340 and the light amount adjustment unit 350 is focused on an image sensor 710. The image sensor 710 converts an optical image into an electrical signal and outputs the electrical signal. The output electrical signal is transmitted to a camera processing circuit 750.

[0100] The camera processing circuit 750 performs amplification, gamma correction, etc. on the output signal from the image sensor 710. The camera processing circuit 750 is connected to a central processing unit (CPU) 790 via an AE gate 755, and is also connected to the CPU 790 via an AF gate 760 and an AF signal processing circuit 765. The video signal that has undergone a predetermined process in the camera processing circuit 750 is transmitted to the CPU 790 through the AE gate 755, the AF gate 760, and the AF signal processing circuit 765. The AF signal processing circuit 765 extracts a high frequency component from the video signal to generate an evaluation value signal for auto focus (AF), and supplies the generated evaluation value signal to the CPU 790.

[0101] The CPU 790 is a control circuit that controls the overall operation of the image capture device 700, and generates a control signal for exposure determination and focusing based on the obtained video signal. The CPU 790 controls the driving of the vibration-type driving devices 620 and 640 and the meter 630 to obtain a determined exposure state and an appropriate focusing state, thereby adjusting the positions of the second lens group 320, the fourth lens group 340, and the light amount adjustment unit 350 in the optical axis direction. Under the control of the CPU 790, the vibration-type driving device 620 moves the second lens group 320 in the optical axis direction, the vibration-type driving device 640 moves the fourth lens group 340 in the optical axis direction, and controls the driving of the light amount adjustment unit 350 through the meter 630.

[0102] The position of the second lens group 320 driven by the vibration type driving device 620 in the optical axis direction is detected by the first linear encoder 770. A notification about the detection result is transmitted to the CPU 790, so that the detection result is fed back under the drive of the vibration type driving device 620. Similarly, the position of the fourth lens group 340 driven by the vibration type driving device 640 in the optical axis direction is detected by the second linear encoder 775, and a notification about the detection result is transmitted to the CPU

[0103] 790, thereby feeding back the detection result under the drive of the vibration drive device 640. The position of the light amount adjustment unit 350 in the optical axis direction is detected by the aperture encoder 780, and a notification about the detection result is transmitted to the CPU 790, thereby feeding back the detection result under the drive of the meter 630.

[0104] The configuration of an electronic device including a member and any one of the above-described vibration-type actuators enables provision of a more compact electronic device.

[0105] Fifth Exemplary Embodiment

[0106] In the fifth exemplary embodiment, an example in which the elastic member 3 is manufactured by compression molding will be described with reference to the drawings.

[0107] The structure and Figure 1 and Figure 2 The configuration shown in FIG. 1 is similar to that shown in FIG. 1 and is described in detail in the first exemplary embodiment. Therefore, the description thereof is omitted in the present exemplary embodiment.

[0108] The protrusion 3 a provided on the elastic member 3 is also described in the first exemplary embodiment, and thus the description thereof will be omitted.

[0109] In the present exemplary embodiment, as described above in the first exemplary embodiment, the outline portion of the elastic member 3 is formed by the shearing process in the press molding.

[0110] FIG. 12A to FIG. 12C Schematic diagrams respectively illustrating shearing processes in press molding. Fig.13A and Fig. 13B 1 and 2 are process diagrams respectively illustrating the process of trimming the rectangular portion and the extending portion of the elastic member from the plate.

[0111] like Fig. 12A The waste 102 of the processed material 101 set in the die is shown in FIG. Fig. 12B The plunger 103 shown descending cuts off. Fig. 12C The diagram shows an enlarged view of the shearing portion at this time. The processed material 101 forms a sag 3B, a shearing surface 3A, a fracture surface 3C, and a burr 3D, and the amount of each component is determined by the amount of the gap (clearance) 105 between the punch 103 and the die 104. Generally, the width of the sag 3B, the area of ​​the shearing surface 3A, the inclination of the fracture surface 3C, and the height of the burr 3D increase as the gap 105 widens, while the width of the sag 3B, the area of ​​the shearing surface 3A, the inclination of the fracture surface 3C, and the height of the burr 3D decrease as the gap 105 narrows.

[0112] In the case where the contour portion of the elastic member 3 is formed by a general shearing process as described above, the contour portion may be formed immediately by performing a shearing process once, or the contour portion may be formed gradually in a plurality of steps. Fig. 13B As shown in FIG. , the elastic member 3 according to the present exemplary embodiment is provided with a corner portion 33 at the tip surface 31b of the extension portion 32 to reduce the size of the vibration actuator. If the elastic member has such a corner portion, the contour portion is usually formed through multiple steps to reduce damage to the mold assembly. Therefore, also in the present exemplary embodiment, by Fig.13A The contour portion is formed through the plurality of steps (a1) to (a4) shown in FIG.

[0113] like Fig.14 As shown in , the amount of the gap 105 can be reduced to form the rectangular portion (rectangular portion side 31a) of the elastic member 3, and the amount of the gap 105 can be increased to form the extension portion tip surface (extension portion tip surface 31b) of the elastic member through multiple steps. The setting value can also be changed depending on the position, and the shape of the contour portion can be determined according to the intended use.

[0114] However, forming by multiple steps may cause the elastic member 3 to be strongly pressed in other processes in the mold and the burr 3D to be flattened (3D'). This phenomenon occurs not only in a progressive mold providing multiple processes for each mold, but also in a single mold providing only one process.

[0115] Fig.15A and Fig. 15BThe diagrams respectively illustrate the state in which the burr is flattened. If the leading edge of the burr (such as the burr 3D') extends in the direction of the columnar portion 6b of the support member 6 of the loose fitting elastic member 3, a sharp interference occurs between the burr 3D' and the columnar portion 6b, which may suppress the vibration of the elastic member 3. The shearing surface 3A is in contact with the elastic member 3 and the columnar portion 6b. Therefore, if the gap 105 is set to an amount that can ensure a larger fracture surface 3C during the shearing process, for example, the leading edge of the flattened burr does not protrude from the shearing surface 3A and the flattened burr does not suppress the vibration.

[0116] On the other hand, if the bonding surface between the elastic member 3 and the piezoelectric element 4 is formed with a wider area, energy can be effectively transmitted. Therefore, it may be necessary to accurately modify (finish) the flat surface of the bonding surface on the elastic member 3 side through a polishing process or the like. Generally speaking, in the case of modifying a flat surface through a polishing process, if the polished surface has a burr 3D (3D'), it is difficult to accurately modify the flat surface. Therefore, it is preferred to modify the sagging surface through polishing. If the amount of the gap 105 is set to a larger value, the amount of the sagging 3B increases, and thus an unpolished portion may be generated. Therefore, as a method of preventing the burr 3D' from protruding from the shear surface 3A, it is not optimal to increase the amount of the gap 105 for the rectangular portion on the bonding surface.

[0117] On the other hand, the tip face 31b of the extension 32 is not a bonding surface to be bonded to the piezoelectric element 4. Therefore, the above countermeasure can be taken so that the tip face 31b can be used for other applications in other processes, for example, positioning between the elastic member 3 and the piezoelectric element 4 during bonding.

[0118] In this exemplary embodiment, on the contact surface between the elastic member 3 and the columnar portion 6b, an inclined surface is formed on the burr portion of the elastic member 3 by burr flattening processing in press molding, thereby avoiding sharp interference between the elastic member 3 and the columnar portion 6b.

[0119] FIG. 16A to FIG. 16C 3D and 3D' are schematic diagrams respectively illustrating burr flattening processing. An example of forming an inclined surface with respect to the burr 3D (3D') will be described. Fig.16A The figure shows the top dead center state during die molding. Fig. 16B The diagram shows a state in the middle of the process. Fig. 16C The diagram shows the bottom dead center state.

[0120] The elastic member 3 including the burr 3D (3D') is pressed down by the descending die 106, and contacts the material press 107 which is caused to slide up and down by a coil spring or the like. Fig. 16BThe elastic member 3 narrowed and pressed between the material press 107 and the die 106 shown in FIG. 1 further descends by following the continuously descending die 106. Then, as shown in FIG. Fig. 16C As shown in FIG. 1 , the burr 3D (3D′) is pressed against the tapered structure 109 provided on the punch 108 , and the inclination of the tapered structure 109 is transferred, thereby forming the inclined surface 3E.

[0121] Fig.17 3E is an enlarged view illustrating a state in which the elastic member 3 having the inclined surface 3E and the columnar portion 6 b are in contact with each other.

[0122] The inclined surface 3E is inclined from the midway position of the fracture surface 3C continuous with the shear surface 3A in the direction away from the support member 6 and toward the slider 9. Since the formation of the inclined surface 3E causes the burr 3D (3D') to plastically flow toward the shear surface 3A, it is necessary to set the burr crushing amount within the range of the space generated between the fracture surface 3C and the columnar portion 6b. In the present exemplary embodiment, for the elastic member having a plate thickness of 0.3 mm, the inclination angle 110 is set to 45 degrees and the inclination depth 111 is set to be less than or equal to 0.05 mm.

[0123] For example, if Fig. 12C If the gap 105 shown in FIG. 1 is narrower than the appropriate value, two independent shearing surfaces can be generated within a single shearing process surface. This is called secondary shearing.

[0124] Fig.18A The figure shows a state where the stamping surface of the elastic member 3 is subjected to secondary shearing. The secondary shearing 3F is flush with the shearing surface 3A, and the burr 3D" on the secondary shearing surface 3F exists at a position closer to the supporting member 6 than the burr 3D. For example, as Fig.18B As shown in , the inclination angle 112 is set to be less than or equal to 45 degrees, thereby enabling active plastic flow to be generated in the direction opposite to the columnar portion 6b.

[0125] The present invention can be appropriately applied to optical devices such as cameras or various electronic devices.

[0126] The present invention is not limited to the above-described embodiments, and various modifications and variations may be made without departing from the spirit and scope of the present invention. Therefore, the claims are attached to disclose the scope of the present invention.

[0127] This application claims priority from Japanese Patent Application No. 2022-113922 filed on July 15, 2022, and cites the contents as a part of this application.

[0128] Explanation of symbols

[0129] 1 Vibration Actuator

[0130] 2.202 Oscillator

[0131] 3 Elastic components

[0132] 3a Protrusion

[0133] 3A Shear Surface

[0134] 3B Droop

[0135] 3C fracture surface (first inclined surface)

[0136] 3D, 3D', 3D" burrs

[0137] 3E Second inclined surface

[0138] 3F Secondary Shear

[0139] 31a Rectangular part side

[0140] 31b Extension tip surface

[0141] 32 Extension

[0142] 33 Extension tip corner

[0143] 4 Piezoelectric element

[0144] 5 Circuit Board

[0145] 6 Supporting members

[0146] 6a Protrusion

[0147] 6b Column

[0148] 62 Adapter

[0149] 7 Compression spring

[0150] 8 Base

[0151] 9 Sliders

[0152] 10 Slider holder

[0153] 11 Ball

[0154] 12 Ball Track

[0155] 13 Combined fixture

[0156] 101 Processed Materials

[0157] 102 Waste

[0158] 103, 108 Punch

[0159] 104, 106 mold

[0160] 105 Gap

[0161] 107 Material Press

[0162] 109 Conical structure

[0163] 110, 112 inclination

[0164] 111 Tilt Depth

[0165] 206 Ring Base

[0166] 208 Wave Washer

[0167] 209 pressure receiving member

[0168] 211 Rotor

[0169] 620, 640 Vibration drive equipment

Claims

1. A vibration actuator, comprising: A vibrator, the vibrator comprising an electro-mechanical energy conversion element and an elastic member; as well as a contact member in contact with the elastic member, wherein vibration of the vibrator allows the contact member and the vibrator to move relative to each other in a first direction, wherein the elastic member includes a rectangular plate portion along the first direction, a protruding portion protruding in a second direction intersecting the first direction, and an extending portion extending from the plate portion in a direction along the first direction, The vibration actuator further includes a supporting member, the supporting member being in contact with at least one of the extension portion and the plate portion to support the vibrator so as to be movable along the second direction, and A portion of the elastic member is provided with a contact surface and an inclined portion, the contact surface contacts the support member along the second direction, and the inclined portion is adjacent to the contact surface and inclined relative to the contact surface in a direction away from the support member.

2. The vibration actuator according to claim 1, wherein: The supporting member includes a protrusion that selectively supports a node common to two different vibration modes in the vibrator.

3. The vibration actuator according to claim 1 or 2, wherein: The columnar portion provided on the supporting member contacts at least one of the extending portion and the plate portion of the elastic member.

4. The vibration actuator according to claim 3, wherein: A plurality of columnar portions supports the elastic member by loosely fitting four corners of the elastic member.

5. The vibration actuator according to claim 1 or 2, wherein: The inclined portion includes inclined portions having different inclination angles or different curvatures, the inclined portions being inclined in a direction away from the support member and being adjacent to each other. 6 . The vibration actuator according to claim 1 , further comprising a hanging portion located on an opposite side of the inclined portion relative to the contact surface, the hanging portion being adjacent to the contact surface.

7. The vibration actuator according to claim 6, wherein: The electro-mechanical energy conversion element is located on a surface of the plate portion that is closer to the hanging portion than the inclined portion.

8. An electronic device, comprising: The vibration actuator according to claim 1 or 2; as well as A member driven by the vibrating actuator.

9. An optical device, comprising: The vibration actuator according to claim 1 or 2; as well as An optical element driven by the vibration actuator.

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