JP2010161857A - Drive system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To sufficiently transmit driving force between a driver and a member to be abutted against, even if a foreign matter enters in between the driver and the member to be abutted against. <P>SOLUTION: The drive system 1 includes a base 10, a stage 11, and an ultrasonic actuator 2, which is fitted to the base 10 and drives the stage 11. The ultrasonic actuator 2 is provided with the actuator body 4 constituted by using a piezoelectric element, the drivers 5 and 5 which are arranged in the actuator body 4 and output driving force to a prescribed driving direction and a support spring 6 supporting the actuator body 4, in a state where the drivers 5 and 5 abut against the stage 11. Rigidity of the support spring 6, in a direction of crossing a circumferential face P where the driver 5 undergoes revolving motion, is lower than that to the driving direction. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a drive device including a vibration type actuator.

  2. Description of the Related Art Conventionally, a driving device including a vibration type actuator is known.

For example, the drive device disclosed in Patent Document 1 includes a vibration type actuator having an actuator body configured using a piezoelectric element. The actuator body is provided with a driving element, and the driving element outputs a driving force by rotating around according to the vibration of the actuator body. This vibration type actuator is attached to the base member in a state where the driving element is in contact with the contacted member. At this time, the actuator body is urged against the contacted member by a spring and is supported so as to be slidable only in the urging direction. In this state, when the driving element is rotated by vibrating the actuator body, the contacted member is driven by the frictional force between the driver and the contacted member.
JP 7-163162 A

  However, in the driving device as described above, when a foreign object enters between the abutted member and the driving element, the pressing force that presses the actuator body against the abutting member by an urging member such as a spring is generated. There is a possibility that the drive member and the contacted member will be worn violently by focusing on the portion of the contacted member where the foreign matter is bitten, or the foreign matter may adhere to the driver or the contacted member. When the driver element or the abutted member is greatly worn, the frictional force between the driver element and the abutted member is reduced in the worn portion, and the transmission of the driving force between the driver element and the abutted member is reduced. It becomes impossible to perform well. In addition, when a foreign object is fixed to the driver element or the contacted member, the driver element cannot properly contact the contacted member at the portion where the foreign object is fixed. The transmission of the driving force with the contact member cannot be performed satisfactorily.

  The present invention has been made in view of such a point, and the object of the present invention is to drive between the driver and the contacted member even if a foreign object enters between the driver and the contacted member. The goal is to have a good force transmission.

  The present invention includes a vibration type actuator, a base member to which the vibration type actuator is attached, and a contacted member with which the vibration type actuator comes into contact, and the base member and the contacted member are driven by the driving force of the vibration type actuator. The drive device in which the contact member moves relatively is an object. The vibration type actuator is configured using a piezoelectric element and generates a plurality of vibrations having different vibration directions. The vibration type actuator is provided in the actuator body and has a plurality of vibration directions according to the vibration of the actuator body. A driving element that outputs a driving force in a predetermined driving direction by rotating in a plane including the driving element, and supports the actuator body with respect to the base member in a state where the driving element is in contact with the contacted body. A support member, and the support member has a rigidity in a direction intersecting with a circumferential surface on which the driver circulates is lower than a rigidity in the drive direction.

  According to the present invention, the rigidity of the support member that supports the actuator body in the direction intersecting the circumferential surface of the driver is made lower than the rigidity of the support member in the drive direction, thereby When foreign matter enters between the driver and the abutted member, the actuator body is easily tilted in a direction intersecting the circumferential surface of the driver, and the foreign matter between the driver and the abutted member. Can be prevented from being bitten firmly. As a result, it is possible to prevent the driver element or the abutted member from being greatly worn out, or to prevent foreign matter from adhering to the driver element or the abutting member, thereby reducing the driving force between the driver element and the abutting member. Good transmission can be performed.

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

Embodiment 1 of the Invention
As shown in FIG. 1, the drive device 1 according to the first embodiment of the present invention includes a base 10, a stage 11, an ultrasonic actuator 2, and a control device 7 that drives and controls the ultrasonic actuator 2. Yes. For example, the driving device 1 is mounted on a camera or the like and used for driving a focus lens.

  The stage 11 is slidably attached to guides 12 and 12 fixed to the base 10 in a state parallel to each other. That is, the stage 11 is configured to be movable along the direction in which the guides 12 and 12 extend. The stage 11 is, for example, a lens frame in a camera, and is not limited to the configuration shown in FIG. The base 10 constitutes a base member, and the stage 11 constitutes a contacted member. The direction in which these guides 12 extend is the relative movement direction of the stage 11. The stage 11 is a plate-like member having a substantially square shape in plan view, and is made of ceramics. The material of the stage 11 is not limited to ceramics, and can be formed using any material. Of the side surfaces of the stage 11, one side surface 14 parallel to the relative movement direction has a first surface 14a and a second surface 14b that intersect each other so that a cross section perpendicular to the relative movement direction is V-shaped. is doing. That is, the side surface 14 is formed with a V-groove that is recessed inward of the stage 11 and extends in the relative movement direction. Driver elements 5 and 5 of the ultrasonic actuator 2 to be described later abut on the side surface 14. The side surface 14 constitutes a contacted surface.

  As shown in FIG. 2, the ultrasonic actuator 2 supports an actuator body 4 that generates vibration, driver elements 5 and 5 that transmit a driving force of the actuator body 4 to the stage 11, and the actuator body 4. And a support spring 6. The ultrasonic actuator 2 constitutes a vibration type actuator (hereinafter the same).

  The actuator body 4 is composed of a piezoelectric element, a pair of substantially rectangular main surfaces facing each other, and a pair of long sides facing each other perpendicular to the main surface and extending in the longitudinal direction of the main surface It has a substantially rectangular parallelepiped shape having a side surface and a pair of opposing short side surfaces extending in the short direction of the main surface perpendicular to both the main surface and the long side surface.

  As shown in FIG. 3, the actuator body 4 is configured by alternately stacking five piezoelectric layers 41, 41,... And four internal electrode layers 42, 44, 43, 44. The internal electrode layers 42, 44, 43, 44 are alternately arranged via the piezoelectric layers 41 in the stacking direction, the first feeding electrode layer 42, the common electrode layer 44, the second feeding electrode layer 43, and the common electrode layer. 44. Each of the first feeding electrode layer 42, the second feeding electrode layer 43, and the common electrode layers 44 and 44 is printed on the main surface of each piezoelectric layer 41.

  Each of the piezoelectric layers 41 is an insulator layer made of a ceramic material such as lead zirconate titanate, and similarly to the actuator body 4, a pair of main surfaces, a pair of long side surfaces, and a pair of It has a substantially rectangular parallelepiped shape having a short side surface. Each piezoelectric layer 41 has a first external electrode 45a at the longitudinal center of one of the long side surfaces and a second external electrode at one longitudinal end of the one long side surface. 46a is formed with a third external electrode 47a at the other longitudinal end of the one long side surface.

  Each common electrode layer 44 has a substantially rectangular shape provided over substantially the entire main surface of the piezoelectric layer 41. In addition, an extraction electrode 44 a that extends from the central part in the longitudinal direction to the external electrode 45 a of the piezoelectric layer 41 is formed on one long side of each common electrode layer 44.

  As shown in FIG. 4, the first feeding electrode layer 42 has a diagonal direction of the main surface of four regions formed by dividing the main surface of the piezoelectric layer 41 into two in the longitudinal direction and the short direction. A pair of first electrodes 42a and 42b formed in one pair of regions, and a conductive electrode 42c that connects and connects the first electrodes 42a and 42b. Each first electrode 42a (42b) is a substantially rectangular electrode and overlaps the common electrode layer 44 when viewed in the stacking direction. That is, each first electrode 42 a (42 b) faces the common electrode layer 44 with the piezoelectric layer 41 interposed therebetween. One of the first electrodes 42a and 42b is provided with an extraction electrode 42d extending to the third external electrode 47a of the piezoelectric layer 41.

  The second feeding electrode layer 43 includes a pair of second electrodes 43a and 43b formed in the other pair of regions of the two pairs of regions located in the diagonal direction of the main surface of the piezoelectric layer 41, and these It has the conduction electrode 43c which connects the 2nd electrodes 43a and 43b and conducts. Of the other pair of regions, an electrode provided in a region adjacent to the short direction of the first electrode 42a and the longitudinal direction of the first electrode 42b when viewed in the stacking direction is the second electrode 43a. An electrode provided in a region adjacent to the longitudinal direction of the first electrode 42a and the lateral direction of the first electrode 42b is the second electrode 43b. Each of the second electrodes 43a (43b) is a substantially rectangular electrode and overlaps the common electrode layer 44 when viewed in the stacking direction. That is, each second electrode 43a (43b) faces the common electrode layer 44 with the piezoelectric layer 41 interposed therebetween. In addition, one of the second electrodes 43a and 43b is provided with an extraction electrode 43d that extends to the second external electrode 46a of the piezoelectric layer 41.

  In the actuator body 4 configured by alternately laminating the piezoelectric layers 41, 41,... And the internal electrode layers 42, 44, 43, 44, the actuator body 4 is formed at the longitudinal center of one long side surface. The first external electrodes 45a of the piezoelectric layers 41 are arranged in the stacking direction to form a group of first external electrodes 45. The first external electrode 45 is electrically connected to lead electrodes 44 a and 44 a formed on the common electrode layers 44 and 44. Similarly, the second external electrode 46a of each piezoelectric body layer 41 is formed in a row in the stacking direction at one end of the long side surface of the actuator body 4 in the longitudinal direction. ing. The second external electrode 46 is electrically connected to the extraction electrode 43 d of the second feeding electrode layer 43. Further, the third external electrode 47a of each piezoelectric layer 41 is arranged in the stacking direction at the other end in the longitudinal direction on the side surface of the one long side of the actuator body 4, and a group of third external electrodes 47 are formed. ing. The third external electrode 47 is electrically connected to the extraction electrode 42d of the first feeding electrode layer 42.

  Then, the other long side surface of the actuator body 4, that is, the long side surface on the side where the external electrodes 45, 46, 47 are not provided (that is, a pair facing the vibration direction of bending vibration described later). One driver surface (hereinafter also referred to as an installation surface) 40a is provided with two driver elements 5,5.

  Each driver 5 is formed in a spherical shape. The driver 5 is made of zirconia, alumina, silicon nitride, silicon carbide, tungsten carbide, or the like. The driver 5 is attached to the installation surface 40a of the actuator body 4 in a point contact manner via an adhesive. Here, the “point contact state” is not limited to the state in which the driver 5 and the installation surface 40a are in strict contact with each other, and an adhesive is interposed between the driver 5 and the installation surface 40a. The state where the child 5 and the installation surface 40a are substantially in point contact is also meant.

  The adhesive is preferably softer than the material of the actuator body 4 and the material of the driver 5. Specific examples include synthetic resins, particularly epoxy resins and silicone resins. By using such a material, it is possible to realize the fixation between the driver 5 and the installation surface 40a without hindering vibration described later of the actuator body 4 as much as possible.

  Further, the positions where the driving elements 5 and 5 are provided are positions on the installation surface 40a that are inward from the both longitudinal ends of the actuator body 4 by a distance of 30 to 35% of the total length of the installation surface 40a. The position of the antinode of the secondary mode of bending vibration, which will be described later, of the actuator body 4 is the position where the vibration becomes the largest.

  As shown in FIG. 1, the actuator body 4 configured in this way has one end of a flexible cable 71 connected to the long side surface where the external electrodes 45 to 47 are provided. It is connected to the control device 7. The control device 7 applies a two-phase AC voltage to the actuator body 4 via the flexible cable 71 at a predetermined frequency, voltage value, and phase difference in order to cause the stage 11 to perform a desired operation.

  Specifically, the actuator body 4 has the first external electrode 45 connected to the ground, the second external electrode 46 has an AC voltage having a predetermined frequency, and the third external electrode 47 has a phase shifted by 90 ° from the AC voltage. AC voltage is applied. By doing so, an alternating current whose phase is shifted by 90 ° between one pair of first electrodes 42a and 42b and the other pair of second electrodes 43a and 43b located in the diagonal direction of the main surface of the piezoelectric layer 41. A voltage is applied to induce longitudinal vibration (so-called stretching vibration) in the longitudinal direction and bending vibration (so-called transverse vibration) in the short direction.

  The resonance frequency of the longitudinal vibration and the resonance frequency of the bending vibration are respectively determined by the actuator body 4, that is, the material, shape, and the like of the actuator body 4. Furthermore, both resonance frequencies are also affected by the force and the supporting portion that support the actuator body 4. Considering these, both resonance frequencies are substantially matched, and an alternating voltage having a frequency in the vicinity thereof is applied to each of the external electrodes 46 and 47 in a state where the phase is shifted by 90 °. For example, the shape of the actuator body 4 is designed so that the resonance frequency of the primary mode of longitudinal vibration (see FIG. 5) matches the resonance frequency of the secondary mode of bending vibration (see FIG. 6), and the resonance By applying an alternating voltage in the vicinity of a frequency with a phase shifted by 90 ° as described above, a primary mode of longitudinal vibration and a secondary mode of bending vibration are induced in the actuator body 4 in a harmonic manner. The shape changes shown in (a), (b), (c), and (d) occur in order.

  As a result, each drive element 5 provided in the actuator body 4 is a plane parallel to the main surface of the actuator body 4, that is, a plane including a longitudinal direction and a short direction (a plane parallel to the paper surface in FIG. , Also referred to as “circumferential surface”), a substantially elliptical motion, that is, a circular motion is performed in P.

  The support spring 6 is configured by a leaf spring and elastically supports the actuator body 4 with respect to the base 10. The support spring 6 is made of, for example, a thin plate made of SUS. Specifically, the support spring 6 includes a flat portion 61 to which the actuator body 4 is attached, and two attachment portions 64 and 64 that are bent and extend from the flat portion 61. The support spring 6 constitutes a support member.

  The flat portion 61 is a plate-like member formed in a rectangular shape, and is joined to the installation surface 40 a of the actuator body 4. The flat portion 61 has openings 62 and 62 formed at positions corresponding to the driver elements 5 and 5. A joining portion 63 for joining the planar portion 61 to the actuator body 4 is formed at a portion sandwiched between the openings 62 and 62 of the planar portion 61.

  The joint portion 63 is joined to a portion between the driver elements 5 and 5 on the installation surface 40a of the actuator body 4 via an epoxy adhesive.

  Here, each opening 62 opens larger than the projected area when the driver 5 is projected onto the flat surface 61 in the short direction of the actuator body 4. By doing so, when the flat surface portion 61 is joined to the actuator body 4, the driver elements 5 and 5 penetrate the flat surface portion 61 through the openings 62 and 62 and do not interfere with the flat surface portion 61. .

  Further, the dimension of each opening 62 in the thickness direction of the actuator body 4 is larger than the thickness of the actuator body 4. Each opening 62 opens larger in the longitudinal direction of the actuator body 4 than the installation surface 40 a of the actuator body 4. That is, in the openings 62 and 62, when the actuator body 4 performs longitudinal vibration and bending vibration as described above, the portion of the actuator body 4 outside in the longitudinal direction from the driver 5 interferes with the flat surface portion 61. It is formed so that there is no.

  The mounting portions 64 are 64 members that are formed to extend continuously from both ends of the long side of the flat surface portion 61. The mounting portions 64 and 64 and the flat portion 61 are bent at an angle of approximately 90 °. Each attachment portion 64 is formed with a through hole 65 for attaching the attachment portion 64 to the base 10 with a screw or the like.

  In the support spring 6 configured as described above, the actuator body 4 is joined to the flat surface portion 61. The support spring 6 to which the actuator body 4 is joined is attached to the base 10 with the driver elements 5 and 5 being in contact with the side surface 14 of the stage 11. Thus, the actuator body 4 is arranged such that its longitudinal direction (that is, the direction of longitudinal vibration) is parallel to the guides 12, 12, that is, parallel to the relative movement direction of the stage 11. At this time, as shown in FIG. 8, each driver element 5 is in contact with the first and second surfaces 14a and 14b forming the V-grooves on the side surface 14, respectively. Specifically, a straight line L connecting the contact portion T1 of each driver element 5 with the first surface 14a and the contact portion T2 with the second surface 14b intersects with the circumferential surface P of the driver element 5 (specifically, Are orthogonal to each other, and the tangent plane between the first surface 14a and the driver 5 (since the first surface 14a is a plane, the first surface 14a itself becomes the tangent plane), the second surface 14b and the driver 5 (the second surface 14b is a flat surface, so the second surface 14b itself is a tangential plane).

  Here, the thickness of the flat portion 61 of the support spring 6 is directed toward the stage 11, and the actuator body 4 is attached to the stage 11 side mainly by the elastic force of the flat portion 61 of the support spring 6. It is energized. That is, the flat portion 61 constitutes an urging portion. Further, the attachment portions 64 and 64 of the support spring 6 are directed in a direction in which the thickness direction is orthogonal to the circumferential surface P of the driver elements 5 and 5 (that is, the thickness direction of the actuator body 4). Therefore, the support spring 6 has elasticity in a direction orthogonal to the circumferential surface P of the driver elements 5 and 5. In other words, the support spring 6 has rigidity in the direction orthogonal to the circumferential surface P, rigidity in the driving direction in which the driving elements 5 and 5 output driving force (that is, the longitudinal direction of the actuator body 4), and actuator. The rigidity in the direction in which the main body 4 is biased (that is, the short direction of the actuator main body 4) is lower.

  Thus, the ultrasonic actuator 2 attached to the base 10 causes the actuator body 4 to generate the longitudinal vibration and the bending vibration as shown in FIG. Then, the stage 11 is driven. Specifically, when the actuator body 4 performs a combined vibration of a longitudinal vibration and a bending vibration, the driver elements 5 and 5 perform a substantially elliptical motion in the circumferential surface P. By doing so, the driving elements 5 and 5 apply a driving force to the stage 11 in the longitudinal direction of the actuator body 4 via the frictional force while periodically increasing and decreasing the frictional force with the stage 11. Has been granted. As a result, the stage 11 moves along the guides 12 and 12. The longitudinal direction of the actuator body 4 (which coincides with the direction in which the guides 12 and 12 extend) corresponds to the driving direction in which the driving elements 5 and 5 output the driving force.

  Hereinafter, the driving of the stage 11 by the ultrasonic actuator 2 will be described in more detail with reference to FIG. When the actuator body 4 extends in the longitudinal direction (vibration direction of longitudinal vibration), the left driver 5 in FIG. 9 (hereinafter also referred to as the left driver 5) is an actuator as shown in FIG. 9B. Since the friction force with the stage 11 is increased and displaced compared to the state before the power supply to the main body 4 (the state in FIG. 9A, hereinafter referred to as the initial state), the stage 11 is moved by the friction force. The left driver 5 in the longitudinal direction is moved to the side to be displaced, that is, the left side in FIG. At this time, the right driver 5 (hereinafter also referred to as the right driver 5) in FIG. 9 is displaced in the longitudinal direction opposite to the left driver 5 (the right side in FIG. 9). Since the frictional force with the stage 11 is reduced or displaced away from the actuator body 4 from the initial state of FIG. 2, the stage 11 is not affected by a frictional force that moves the stage 11, and the stage 11 11 is not moved by the right driver 5.

  On the other hand, when the actuator body 4 contracts in the longitudinal direction, the right driver 5 is displaced by increasing the frictional force with the stage 11 as compared with the initial state of the actuator body 4 as shown in FIG. Therefore, the stage 11 is moved to the side where the right driver 5 is displaced in the longitudinal direction, that is, the left side in FIG. 9 by this frictional force. This moving direction is the same as the moving direction of the stage 11 by the left driver 5 when the actuator body 4 is extended as described above. On the other hand, the left driver 5 is displaced in the longitudinal direction opposite to the right driver 5 (the right side in FIG. 9), but the frictional force with the stage 11 is reduced compared to the initial state of the actuator body 4, Alternatively, the stage 11 is displaced away from the actuator body 4, so that the stage 11 is not affected by the frictional force that moves the stage 11, and the stage 11 cannot be moved by the left driver 5.

  In FIG. 9, the driver 5 that does not affect the movement of the stage 11 is separated from the stage 11, but is not necessarily separated.

  Thus, one driver element 5 and the other driver element 5 alternately move the stage 11 in a predetermined direction in a state where the phases are shifted by 180 °. By applying the AC voltage to the external electrodes 46 and 47 with the phase shifted by −90 °, the driving force output by the driver elements 5 and 5 can be reversed, and the stage 11 is moved in the other direction. Can be moved to.

  The moving amount, moving speed, and moving acceleration of the stage 11 are adjusted by adjusting at least one of the voltage value, frequency, and feeding time of the AC voltage that is fed to the second and third external electrodes 46 and 47, or It can be adjusted by changing the phase shift of each AC voltage supplied to the third external electrodes 46 and 47.

  As described above, the ultrasonic actuator 2 causes the driver elements 5 and 5 to rotate around the rotating surface P including the vibration direction (longitudinal direction) of longitudinal vibration and the vibration direction (short direction) of bending vibration. The stage 11 is driven while repeatedly increasing and decreasing the frictional force between 5 and 5 and the stage 11.

  Further, since the actuator body 4 is urged to the stage 11 side by the elastic force of the support spring 6 and the driver elements 5 and 5 are pressed against the stage 11, the ultrasonic actuator 2 is not driven when the stage 11 is not driven. The state of the stage 11 is held by a static frictional force with the driver elements 5 and 5. That is, the stage 11 does not move when not driven.

  Here, the operation of the ultrasonic actuator 2 when a foreign substance enters between the stage 11 and the driving elements 5 and 5 will be described with reference to FIGS.

  As described above, each driver element 5 is in contact with the first and second surfaces 14a and 14b forming the V-grooves on the side surface 14 of the stage 11, as shown in FIG. Here, since the rigidity of the support spring 6 in the direction orthogonal to the circumferential surface P of the driver 5 is lower than the rigidity in the driving direction and the rigidity in the biasing direction, the first and second surfaces 14a. , 14b and when the foreign object enters between the driver element 5, for example, when the foreign object enters between the first surface 14a and the driver element 5, the actuator body 4 is, as shown in FIG. The driver 5 is easily tilted in the direction perpendicular to the circumferential surface P of the driver 5 (that is, the thickness direction of the actuator body 4) so that the driver 5 rides on the foreign matter. Specifically, the actuator body 4 is arranged so that the long side surface side of the actuator body 4 on which the driver element 5 is not provided is displaced in a direction perpendicular to the circumferential surface P of the driver element 5 around the driver element 5. Tilt. Further, since the driver element 5 is in contact with the side surface 14 at two contact portions T1 and T2 arranged in a direction orthogonal to the circumferential surface P, the actuator body 4 is directed in a direction orthogonal to the circumferential surface P of the driver element 5. Even if it tilts, the contact state between the driver 5 and the side surface 14 (in this example, the second surface 14b) is maintained. As a result, the stage 11 can be driven, and the driver 5 can not only ride on the foreign matter that has entered between the first surface 14a but also can get over the foreign matter.

  Therefore, according to the present embodiment, even if a foreign object enters between the driver element 5 and the side surface 14 of the stage 11, the contact state between the driver element 5 and the side surface 14 while the driver element 5 rides on the foreign object. Therefore, the driving force from the driver 5 to the stage 11 can be satisfactorily transmitted without concentrating the pressing force acting on the actuator body 4 on the portion of the driver 5 and the side surface 14 where foreign matter has entered. Can do. As a result, it is possible to make the driver 5 get over the foreign object while driving the stage 11 with the driver 5.

  Here, the rigidity of the support spring 6 in the direction orthogonal to the circumferential surface P is made lower than the rigidity in the driving direction and the rigidity in the biasing direction, so that the drive element 5 drives the stage 11. The reaction force when the force is output is firmly received by the support spring 6, the driving force is appropriately output to the stage 11, and the actuator body 4 is driven while appropriately biasing the actuator body 4 with respect to the stage 11. It can be easily tilted in a direction orthogonal to the circumferential surface P of the child 5.

<< Modification 1 >>
Subsequently, Modification 1 of Embodiment 1 will be described. The ultrasonic actuator 202 according to Modification 1 is different from the first embodiment in the structure of the support spring 206. Therefore, the same configurations as those of the first embodiment are denoted by the same reference numerals, description thereof is omitted, and different configurations are mainly described.

  FIG. 11 is a perspective view of the ultrasonic actuator 202 according to the first modification.

  The support spring 206 is configured by a leaf spring, like the support spring 6. The support spring 206 includes a flat portion 261 to which the actuator body 4 is attached, and four attachment portions 264, 264,... That are bent and extend from the flat portion 261.

  The plane portion 261 has the same configuration as the plane portion 61 of the support spring 6. That is, the flat portion 261 is a plate-shaped member formed in a rectangular shape, and is joined to the installation surface 40 a of the actuator body 4. The flat portion 261 has openings 262 and 262 at positions corresponding to the driver elements 5 and 5. A joint portion 263 for joining the flat portion 261 to the actuator body 4 is formed at a portion sandwiched between the openings 262 and 262 of the flat portion 261.

  The mounting portions 264, 264,... Are thin plate-like members formed continuously extending from both ends of the long side of the flat portion 261. Specifically, in each of the opposing long sides of the flat surface portion 261, the two attachment portions 264 and 264 continuously extend from both end portions of the long side. These mounting portions 264, 264,... And the plane portion 261 are bent at an angle of approximately 90 °. Each attachment portion 264 is formed with a through hole (not shown) for attaching the attachment portion 264 to the base 10 with a screw or the like.

  The support spring 206 configured in this manner is attached to the base 10 so that the actuator body 4 is joined to the flat surface portion 261 and the driver elements 5 and 5 of the actuator body 4 abut against the side surface 14 of the stage 11. Yes. Specifically, the support spring 206 is configured so that the base 10 is sandwiched between the mounting portions 264 and 264 extending from one long side of the plane portion 261 and the mounting portions 264 and 264 extending from the other long side of the plane portion 261. Attached to the base 10.

  As a result, the actuator body 4 is urged toward the stage 11 by the elastic force of the support spring 206. In the support spring 6 according to the first embodiment, one long side of the flat surface portion 61 is a free end, whereas the support spring 206 is attached to both long sides of the flat surface portion 261 with mounting portions 264 and 264. ,... Are higher than the support spring 6, the rigidity of the actuator body 4 in the biasing direction (that is, the short direction of the actuator body 4) is higher. However, the support spring 206 supports the actuator body 4 in a cantilever state, and the thickness direction of the thin plate-like mounting portions 264, 264,... Is perpendicular to the circumferential surface P of the driver elements 5, 5 (that is, the actuator The rigidity of the support spring 206 in the direction orthogonal to the circumferential surface P of the driving elements 5 and 5 is the rigidity in the driving direction (that is, the longitudinal direction of the actuator body 4). The rigidity in the biasing direction (that is, the short direction of the actuator body 4) is lower.

  That is, even if the actuator main body 4 is supported by the support spring 206 according to the first modification, the actuator main body 4 is moved to the driver element when a foreign object enters between the driver element 5 and the side surface 14 of the stage 11. 5 can be easily tilted in a direction perpendicular to the circumferential surface P of the drive line 5 to allow the driver 5 to ride on the foreign matter.

<< Modification 2 >>
Subsequently, Modification 2 of the embodiment will be described. The ultrasonic actuator 302 according to the second modification differs from the first modification in the structure for attaching the support spring 306 to the base 10. Therefore, the same configurations as those of the first modification are denoted by the same reference numerals, description thereof is omitted, and different configurations are mainly described.

  FIG. 12 is a perspective view of the ultrasonic actuator 302 according to the second modification.

  The support spring 306 is configured by a leaf spring, like the support spring 206. The support spring 306 has a flat surface portion 361 to which the actuator body 4 is attached, and four attachment portions 364, 364,... That are bent and extend from the flat surface portion 361.

  The plane portion 361 has the same configuration as the plane portion 261 of the support spring 206. That is, the flat portion 361 is a plate-like member formed in a rectangular shape, and is joined to the installation surface 40 a of the actuator body 4. The flat portion 361 has openings 362 and 362 at positions corresponding to the driver elements 5 and 5. A joining portion 363 for joining the planar portion 361 to the actuator body 4 is formed at a portion between the opening portions 362 and 362 of the planar portion 361.

  The mounting portions 364, 364,... Are thin plate-like members formed continuously extending from both ends of the long side of the flat surface portion 361. Specifically, in each of the opposing long sides of the plane portion 361, three attachment portions 364 and 364 continuously extend from both end portions of the long side. These mounting portions 364, 364,... And the plane portion 361 are bent at an angle of approximately 90 °. Then, the tip end portion (the end portion opposite to the end portion connected to the flat surface portion 361) of each attachment portion 364 faces the outside (the opposite side to the attachment portion 364 facing each other in the thickness direction of the actuator body 4). And bent at an angle of approximately 90 °. And the through-hole (illustration omitted) for attaching the attaching part 364 to the base 10 with a screw etc. is formed in this bent front-end | tip part.

  The support spring 306 configured in this manner is attached to the base 10 so that the actuator body 4 is joined to the flat portion 361 and the driver elements 5 and 5 of the actuator body 4 abut against the side surface 14 of the stage 11. Yes. Specifically, the support spring 306 is attached to the attachment surface of the base 10 substantially parallel to the plane portion 361 via attachment portions 364, 364,.

  As described above, by using the support spring 306 according to the second modification, the actuator main body 4 can be attached to the attachment surface of the base 10 different from the embodiment and the first modification.

  Further, the rigidity of the support spring 306 is the same as that of the support spring 206 according to the first modification. Therefore, as in the first embodiment and the first modification, when a foreign object enters between the driver element 5 and the side surface 14 of the stage 11, the actuator body 4 can be easily moved in a direction orthogonal to the circumferential surface P of the driver element 5. It is possible to cause the driver 5 to ride on the foreign matter.

<< Modification 3 >>
Subsequently, Modification 3 of the embodiment will be described. The drive device 401 according to the modification 3 is different from the first embodiment in the contact structure between the ultrasonic actuator and the stage. Therefore, the same configurations as those of the first embodiment are denoted by the same reference numerals, description thereof is omitted, and different configurations are mainly described.

  FIG. 13 is a schematic cross-sectional view of the driving device 401 perpendicular to the relative movement direction of the stage 411.

  The stage 411 according to the modification 3 includes a first side surface 414 that is parallel to the relative movement direction among the side surfaces, and intersects with each other so that a line of intersection with a plane orthogonal to the relative movement direction has a mountain shape. A surface 414a and a second surface 414b are provided. That is, the side surface 414 has a shape protruding outward from the stage 411.

  The ultrasonic actuator 402 includes four driver elements 5 and 5 (only two elements arranged in a direction orthogonal to the circumferential surface P are shown in FIG. 13). Two of these four driver elements 5 and 5 are provided at positions of antinodes of the secondary mode of bending vibration of the actuator body 4 at two locations on the installation surface 40 a of the actuator body 4. Specifically, the two driver elements 5 and 5 provided at each position are arranged in a direction orthogonal to the circumferential surface P of the driver element 5 (that is, the thickness direction of the actuator body 4).

  In the ultrasonic actuator 402 configured as described above, one driver 5 of the two drivers 5, 5 arranged in the thickness direction of the actuator body 4 abuts on the first surface 414 a of the stage 411, and the other driver 5 is supported by the base 10 in contact with the second surface 414b of the stage 411.

  That is, also in the third modification, the driver elements 5 and 5 of the ultrasonic actuator 402 and the stage 411 are in contact with each other at two locations in the direction intersecting the circumferential surface P of the driver element 5 (that is, one driver element). The straight line L connecting the contact portion T1 between the first drive surface 5 and the first surface 414a of the stage 411 and the contact portion T2 between the other drive element 5 and the second surface 414b of the stage 411 is a circumferential surface P of the drive element 5. The tangential planes (that is, the first surface 414a and the second surface 414b) at the respective contact portions intersect each other. Therefore, foreign matter enters between the driver elements 5, 5 and the first or second surface 414 a, 414 b, and the ultrasonic actuator 402 tilts in a direction orthogonal to the circumferential surface P of the driver element 5 due to the elasticity of the support spring 6. Even when this is done, the driver 5 is in contact with one of the first and second surfaces 414a, 414b, and the contact between the driver 5 and the side surface 414 of the stage 411 can be maintained. . As a result, it is possible to make the driver 5 get over the foreign object while driving the stage 411 with the driver 5.

  Note that the shape of the side surface 414 is not limited to this, and a ridge formed by the first surface 414a and the second surface 414b may be chamfered or rounded. Alternatively, the side surface 414 may include a surface other than the first surface 414a and the second surface 414b, and another surface or surfaces are interposed between the first surface 414a and the second surface 414b. Also good.

  Furthermore, as shown in FIG. 14, the side surface 414 may be a curved surface in which a line of intersection with a plane orthogonal to the relative movement direction is a curve. Even in such a configuration, the driver elements 5 and 5 of the ultrasonic actuator 402 and the stage 411 are in contact with each other at two locations in the direction intersecting the circumferential surface P of the driver element 5, and contact at each contact portion. The planes intersect each other.

<< Embodiment 2 of the Invention >>
Next, the driving device 501 according to the second embodiment of the present invention will be described. The driving device 501 according to the second embodiment is different from the first embodiment in the support structure of the stage 511. Therefore, the same configurations as those of the first embodiment are denoted by the same reference numerals, and the description thereof is omitted, and different configurations are mainly described.

  FIG. 15 is an exploded perspective view of the drive device 501, and FIG. 16 is a cross-sectional view of the drive device 501.

  The drive device 501 includes a stage 511, two first and second ultrasonic actuators 2A and 2B, and a control device (not shown) that drives and controls the ultrasonic actuators 2A and 2B.

  Unlike the stage 11 of the first embodiment, the stage 511 is not supported by the guides 12 and 12, but is supported by the two ultrasonic actuators 2A and 2B. A V-groove extending in the relative movement direction is formed on each of the pair of first and second side surfaces 14 and 15 parallel to the relative movement direction of the stage 511 among the side surfaces of the stage 511. That is, the first side surface 14 has a first surface 14a and a second surface 14b that intersect each other so that a cross section perpendicular to the relative movement direction is V-shaped, and the second side surface 15 has the relative movement. It has the 1st surface 15a and the 2nd surface 15b which mutually cross | intersect so that the cross section orthogonal to a direction may become V shape.

  The first and second ultrasonic actuators 2A and 2B have the same configuration as the ultrasonic actuator 2 of the first embodiment. However, in the second ultrasonic actuator 2B, the actuator body 4 is attached to the surface opposite to the extending direction of the attachment portions 64, 64 with respect to the flat portion 61 of the support spring 6, and the driver elements 5, 5 are flat portions. It projects from the openings 62 and 62 of the 61 in the direction in which the mounting portions 64 and 64 extend. The first ultrasonic actuator 2 </ b> A is similar to the ultrasonic actuator 2 in that the actuator body 4 is attached to the surface on the side where the attachment portions 64, 64 extend with respect to the flat portion 61 of the support spring 6. 5 protrudes from the openings 62 and 62 of the plane portion 61 to the opposite side to the direction in which the attachment portions 64 and 64 extend.

  In the first and second ultrasonic actuators 2A and 2B, the support springs 6 and 6 are attached to the base 10 with the drive elements 5 and 5 and the drive elements 5 and 5 facing each other. Yes. At this time, the mounting portions 64 and 64 of the first ultrasonic actuator 2A and the mounting portions 64 and 64 of the second ultrasonic actuator 2B are overlapped and fastened to the base 10 together with fixing screws.

  The stage 511 is supported by the first and second ultrasonic actuators 2A and 2B arranged as described above. Specifically, the driver elements 5 and 5 of the first ultrasonic actuator 2A abut on the first side surface 14 of the stage 511, while the driver elements 5 and 5 of the second ultrasonic actuator 2B contact the second side surface 15 of the stage 511. Touching. At this time, each driver 5 of the first ultrasonic actuator 2 </ b> A is in contact with both the first surface 14 a and the second surface 14 b of the first side surface 14. Each driver 5 of the second ultrasonic actuator 2B is in contact with both the first surface 15a and the second surface 15b of the second side surface 15.

  In this state, the stage 511 is driven along the longitudinal direction of the actuator body 4 by operating the first and second ultrasonic actuators 2A and 2B so as to output the same magnitude of driving force in the same direction. Can do.

  Here, the stage 511 is sandwiched between the drive elements 5 and 5 of the first ultrasonic actuator 2A and the drive elements 5 and 5 of the second ultrasonic actuator 2B from both sides along the direction orthogonal to the relative movement direction. Each driver 5 abuts against the side surface 14 (or side surface 15) of the stage 511 at two abutting portions T1 and T2 in a direction perpendicular to the plane including the relative movement direction and the clamping direction. By configuring as described above, the stage 511 can be moved in the relative movement direction in a state in which displacement in the direction perpendicular to the holding direction and the plane including the relative movement direction and the holding direction is restricted. Can be supported. By doing so, the stage 511 can be movably supported by the first and second ultrasonic actuators 2A and 2B without providing the guides 12 and 12 in the first embodiment.

  Also in the second embodiment, each of the first and second ultrasonic actuators 2A and 2B is supported in a cantilever state from the base 10 via the support spring 6, and the mounting portion 64 of each support spring 6 is Since the thickness direction faces the direction perpendicular to the circumferential surface P of the driver 5, the first and second ultrasonic actuators 2A and 2B can easily tilt in the direction perpendicular to the circumferential surface P of the driver 5. Can do. Therefore, even if foreign matter enters between the driver 5 of the first ultrasonic actuator 2A and the first side face 14 or between the driver 5 of the second ultrasonic actuator 2B and the second side face 15, the actuator body 4 can be tilted in a direction orthogonal to the circumferential surface P of the driver 5 to drive the driver 5 onto a foreign object. Then, each driver element 5 of the first ultrasonic actuator 2 </ b> A has two positions (specifically, the first surface 14 a and the second surface 14 b) with respect to the side surface 14 in a direction orthogonal to the circumferential surface P of the driver element 5. In addition to being in contact, the tangent planes at the two contact portions intersect each other, so that the actuator body 4 tilts in a direction perpendicular to the circumferential surface P of the drive element 5 and the drive element 5 rides on the foreign matter. However, the contact state between the driver 5 and the side surface 14 can be maintained in one of the two contact portions, and the stage 511 can be driven. For this reason, even when the driver element 5 rides on the foreign object, the stage 511 can be driven to allow the driver element 5 to get over the foreign object. Similarly, each driver element 5 of the second ultrasonic actuator 2B is located at two locations in the direction orthogonal to the circumferential surface P of the driver element 5 (specifically, the first surface 15a and the second surface 15b) with respect to the side surface 15. And the tangent planes at the two abutting portions intersect each other, so that the actuator body 4 tilts in a direction perpendicular to the circumferential surface P of the driver 5 and the driver 5 rides on the foreign matter. Even so, in one of the two contact portions, the contact state between the driver 5 and the side surface 15 can be maintained, and the stage 511 can be driven. For this reason, even when the driver element 5 rides on the foreign object, the stage 511 can be driven to allow the driver element 5 to get over the foreign object.

  Therefore, according to the second embodiment, even if foreign matter enters between the driver 5 and the first and / or second side surfaces 14 and 15 of the stage 511, the driver 5 is driven while riding on the foreign matter. Since the contact state between the elements 5 and 5 and the first and second side surfaces 14 and 15 can be maintained, the pressing force acting on the actuator body 4 is applied to the driver elements 5 and 5 and the first and second side surfaces 14 and 15. The driving force can be satisfactorily transmitted from the driver 5 to the stage 511 without being concentrated on the portion where the 15 foreign matter has entered. As a result, it is possible to make the driver 5 get over the foreign object while driving the stage 511 with the driver 5.

  Here, the rigidity of the support spring 6 in the direction orthogonal to the circumferential surface P of the driver element 5 is made lower than the rigidity in the driving direction of the driver element 5 and the rigidity in the biasing direction to the actuator body 4. The reaction force when the driving force is output from the driver 5 to the stage 511 is firmly received by the support spring 6 so that the driving force is appropriately output to the stage 511 and the actuator body 4 is appropriately applied to the stage 511. The actuator body 4 can be easily tilted in a direction perpendicular to the circumferential surface P of the driver 5 while being urged.

  Furthermore, since the stage 511 can be configured without providing the guides 12 and 12, the configuration of the stage 511 can be simplified.

  The support structure for the first and second ultrasonic actuators 2A and 2B is not limited to the above structure. For example, the support spring 6 of the first ultrasonic actuator 2A and the support spring 6 of the second ultrasonic actuator 2B do not need to be fastened together with the base 10, and the mounting portion of the support spring 6 of the second ultrasonic actuator 2B is not required. 64 and 64 may be configured to extend on the side opposite to the attachment portions 64 and 64 of the support spring 6 of the first ultrasonic actuator 2 </ b> A, and may be separately attached to the base 10.

<Modification>
Next, a modification of the drive device according to the second embodiment will be described. The driving device 601 according to the modification 2 is different from the second embodiment in the support structure of the stage 511. Therefore, the same configurations as those of the second embodiment are denoted by the same reference numerals, description thereof is omitted, and different configurations are mainly described.

  FIG. 17 shows a cross-sectional view of the driving device 601.

  A driving device 601 according to the modification includes a stage 511, an ultrasonic actuator 2, a guide member 8 that guides the stage 511, and a control device (not shown) that controls the driving of the ultrasonic actuator 2. .

  The ultrasonic actuator 2 has the same configuration as the ultrasonic actuator 2 according to the first embodiment.

  The guide member 8 has a support spring 81 and two rolling elements 82.

  The support spring 81 is a leaf spring, similar to the support spring 6, and is composed of, for example, a thin plate made of SUS. Specifically, the support spring 81 includes a flat portion 83 and two attachment portions 84 that are bent and extend from the flat portion 83. The plane part 83 is a plate-like member formed in a rectangular shape, and supports the rolling element 82 in a freely rotatable manner. The two attachment portions 84 are thin plate-like members formed continuously extending from both end portions of the long side of the flat portion 83. The mounting portion 84 and the flat portion 83 are bent at an angle of about 90 °. Each attachment portion 84 is formed with a through hole 85 for attaching the attachment portion 84 to the base 10 with a screw or the like.

  The rolling element 82 is composed of a metal spherical member. The two rolling elements 82 are arranged side by side in the longitudinal direction of the flat portion 83 of the support spring 81.

  The support spring 6 and the support spring 81 are attached to the base 10 with the driver 5 of the ultrasonic actuator 2 and the rolling element 82 of the guide member 8 facing each other. The stage 511 is supported by the ultrasonic actuator 2 and the guide member 8 arranged in this manner. Specifically, the driver 5 of the ultrasonic actuator 2 contacts the first side surface 14 of the stage 511, while the rolling element 82 of the guide member 8 contacts the second side surface 15 of the stage 511. At this time, each driver 5 of the ultrasonic actuator 2 is in contact with both the first surface 14 a and the second surface 14 b of the first side surface 14. Each rolling element 82 of the guide member 8 is in contact with both the first surface 15 a and the second surface 15 b of the second side surface 15.

  In this state, the stage 511 can be driven along the longitudinal direction of the actuator body 4 by operating the ultrasonic actuator 2.

  Here, the stage 511 is sandwiched between the drive element 5 of the ultrasonic actuator 2 and the rolling element 82 of the guide member 8 from both sides along the direction orthogonal to the relative movement direction. 14 and abutting at two abutting portions T1 and T2 in a direction orthogonal to the plane including the relative movement direction and the sandwiching direction, and the rolling element 82 is in contact with the side surface 15 of the stage 511. By configuring the stage 511 to be in contact with the two abutting portions T1 and T2 in a direction orthogonal to the plane including the relative movement direction and the clamping direction, the stage 511 is held in the clamping direction and the relative movement. In a state in which displacement in a direction orthogonal to the plane including the direction and the sandwiching direction is restricted, it can be supported so as to be movable in the relative movement direction. By doing so, the stage 511 can be supported movably by the ultrasonic actuator 2 and the guide member 8 without providing the guides 12 and 12 in the first embodiment.

  In addition, the rolling element 82 does not need to be spherical, and may be a cylindrical roller. In the case where the rolling element 82 is configured by rollers, in order to abut on the second side surface 15 of the stage 511 at a plurality of abutting portions in a direction orthogonal to the circumferential surface P of the driver element 5, the driver element 5 It is necessary to provide two or more rollers lined up in a direction orthogonal to the circumferential surface. That is, it is necessary to provide the roller that contacts the first surface 15 a of the second side surface 15 and the roller that contacts the second surface 15 b of the second side surface 15 side by side in a direction orthogonal to the circumferential surface of the driver element 5.

  Note that a modification of the first embodiment may be adopted in the second embodiment.

<< Other Embodiments >>
The present invention may be configured as follows with respect to the embodiment.

  The configuration of the support spring is not limited to the above embodiment. Any configuration can be adopted as long as it has a configuration that supports the actuator body 4 and has a rigidity in a direction intersecting the circumferential surface of the drive element 5 lower than a rigidity in the drive direction of the drive element 5. Further, the mounting structure between the support spring and the actuator body 4 is not limited to the above embodiment. For example, the support spring may be joined to a surface other than the installation surface 40 a of the actuator body 4. Moreover, the structure which accommodates the actuator main body 4 in a case, and joins a support spring to this case may be sufficient.

  Moreover, in the said embodiment, although the support member of the actuator main body 4 is comprised by the support spring which consists of leaf | plate springs, it is not restricted to this. For example, the support member may be made of a material such as rubber and having elastic anisotropy whose rigidity in a direction intersecting the circumferential surface of the driver element 5 is lower than that of the driver element 5 in the driving direction. Also good. Moreover, you may comprise a support member combining the member which has the elasticity to the direction which cross | intersects the surrounding surface of the driver element 5 at least, and the mechanism which controls the displacement to the other direction.

  Further, in the above-described embodiment, the driver element 5 (in addition to the rolling element 82 in the modified example of the embodiment 2) and the side surface of the stage are arranged at two locations where the driver element 5 is aligned in a direction perpendicular to the circumferential surface P of the driver element 5. Although it contacts in a contact part, it is not restricted to this. That is, it is sufficient that the straight line L connecting the two contact portions intersects with the circumferential surface P, and does not necessarily need to be orthogonal. For example, in the third modification of the first embodiment, the two driver elements 5 and 5 provided at the antinodes of the bending vibration on the installation surface 40 a of the actuator body 4 are provided shifted in the longitudinal direction of the actuator body 4. The straight line L connecting the contact portion T1 between one driver element 5 and the first surface 414a of the stage 411 and the contact portion T2 between the other driver element 5 and the second side surface 414b of the stage 411 is a driver element 5 You may be comprised so that it may incline with respect to the normal line of the surrounding surface P.

  Moreover, in the said embodiment, in the actuator main body 4, the external electrodes 45-47 are formed in one long side surface, and it supplies with electricity to this external electrodes 45-47 by the flexible cable 71, However, it is restricted to this is not. Any configuration can be adopted as long as a voltage can be applied to the piezoelectric layer.

  Furthermore, the shape, number, material, and the like of the driver element 5 are not limited to the above-described embodiment, and a driver element having an arbitrary shape, number, material, and the like can be employed.

  Further, although the ultrasonic actuator 2 is configured to harmoniously generate the primary mode of longitudinal vibration in the longitudinal direction and the secondary mode of flexural vibration in the actuator body 4, it is not limited to this. Any vibration type or vibration mode may be used as long as it is a vibration type actuator that vibrates the actuator body 4 and outputs a driving force via a frictional force between the driver 5 and the stage 11. The configuration can be adopted.

  Furthermore, the actuator body 4 is configured by laminating piezoelectric layers. However, the actuator body 4 has a structure in which a piezoelectric element is attached to a substrate such as metal, or a structure in which a resonator is formed of metal and sandwiches the piezoelectric element. There may be. In this case, the resonator including the piezoelectric element constitutes the actuator body.

  Moreover, in the said embodiment, although the two drive elements 5 and 5 are provided in the long side surface of the actuator main body 4, it is not restricted to this. For example, one driver element 5 may be provided on the short side surface of the actuator body 4. In this case, the actuator body 4 is disposed such that the driver 5 abuts against the stage in a posture in which the short side direction coincides with the relative movement direction of the stage. Such an ultrasonic actuator drives the stage 11 in the short direction of the actuator body 4.

  Further, in the above-described embodiment, the ultrasonic actuator 2 is fixed to the base 10 and the driver elements 5 and 5 are brought into contact with the movable stage 11 to operate the ultrasonic actuator 2 so that the stage 11 is moved. Although driven, the ultrasonic actuator 2 may be fixed to the stage 711 as shown in FIG. Specifically, the drive device 701 includes guides 12 and 12 fixed to a base (not shown) in a parallel state, a stage 711 slidably attached to the guides 12 and 12, and the ultrasonic actuator 2. And. One guide 12 of the guides 12 and 12 is provided with a contacted member 713 fixed to the guide 12. Of the side surfaces of the contacted member 713, one side surface 714 parallel to the relative movement direction of the stage 711 has a first surface 714a and a second surface intersecting each other such that a cross section perpendicular to the relative movement direction is V-shaped. Surface 714b. That is, the side surface 714 is formed with a V-groove that is recessed inward of the contacted member 713 and extends in the relative movement direction. On the other hand, the stage 711 is provided with an actuator mounting portion 711a. The actuator body 4 is attached to the actuator attachment portion 711a of the stage 711 via the support spring 6 with the driver elements 5 and 5 coming into contact with the side surface 714 of the contacted member 713. At this time, each driver 5 is in contact with the first surface 714 a and the second surface 714 b of the side surface 714. When the ultrasonic actuator 2 is operated in this state, the driving elements 5 and 5 output a driving force to the contacted member 713, but the contacted member 713 is fixed. 2 itself vibrates in the longitudinal direction of the guides 12, 12 relative to the abutted member 713. As a result, the stage 711 connected to the actuator body 4 via the actuator mounting portion 711 a is driven in the longitudinal direction of the guides 12 and 12. The stage 711 constitutes a base member.

  Moreover, in the said embodiment, although the stage 11 from which the driving force of an ultrasonic actuator is output is flat form, it is not restricted to this, Arbitrary structures can be employ | adopted as a structure of a to-be-contacted member. it can. For example, as shown in FIG. 19, the abutted member is a disc body 811 that can be rotated about a predetermined axis X, and the driver elements 5, 5 of the ultrasonic actuator are on the side peripheral surface of the disc body 811. A driving device 801 configured to abut on 814 may be employed. In such a configuration, when the ultrasonic actuator is driven, the disk body 811 is rotated about the predetermined axis X by the substantially elliptical motion of the driver elements 5 and 5. That is, the circumferential direction around the axis X is the relative movement direction of the disc body 811. The disk body 811 constitutes a contacted member, and the side peripheral surface 814 forms a contacted surface.

  Here, the side peripheral surface 814 of the disk body 811 has a first surface 814a and a second surface 814b that intersect each other so that a cross section orthogonal to the relative movement direction is V-shaped. That is, the side circumferential surface 814 is formed with a V-groove that is recessed inwardly of the disk body 811 and extends in the circumferential direction of the disk body 811. Each driver element 5 is in contact with the first surface 814 a and the second surface 814 b of the side peripheral surface 814.

  As shown in FIG. 20, the abutted member is a disc body 911 that can rotate about a predetermined axis X, and the driving elements 5, 5 of the ultrasonic actuator 2 are planar portions of the disc body 911. A driving device 901 configured to contact the 914 may be employed. In the case of such a configuration, when the ultrasonic actuator 2 is driven, the disk body 911 is driven in a tangential direction at the contact portion with the driver elements 5, 5 by the substantially elliptical motion of the driver elements 5, 5. The plate body 911 is rotated around a predetermined axis X. The circumferential direction around the axis X is the relative movement direction of the disk body 911. The disc body 20 constitutes a contacted member, and the flat portion 914 forms a contacted surface.

  Here, although not illustrated, the flat surface portion 914 of the disk body 911 has a first surface and a second surface intersecting each other so that a cross section perpendicular to the relative movement direction is V-shaped. ing. That is, the flat surface portion 914 is formed with a V-groove that is recessed inwardly of the disk body 911 and extends in the circumferential direction of the disk body 911. Each driver 5 is in contact with the first surface and the second surface of the flat surface portion 914.

  In addition, the above embodiment is an essentially preferable illustration, Comprising: It does not intend restrict | limiting the range of this invention, its application thing, or its use.

  As described above, the present invention is useful for a drive device including a vibration type actuator.

It is a perspective view of the drive device concerning Embodiment 1 of the present invention. It is a perspective view of an ultrasonic actuator. It is a disassembled perspective view of an actuator main body. It is a schematic front view which shows schematic structure of an actuator main body. It is a conceptual diagram which shows the displacement by the primary mode of the longitudinal vibration to the longitudinal direction of an actuator main body. It is a conceptual diagram which shows the displacement by the secondary mode of the bending vibration of an actuator main body. It is a conceptual diagram which shows operation | movement of an actuator main body. It is sectional drawing in the VIII-VIII line of FIG. It is a conceptual diagram for demonstrating the drive of the stage by an ultrasonic actuator, Comprising: (a) is the state before a drive, (b) drives a stage by one driver, when an actuator main body expand | extends to a longitudinal direction. State (c) shows a state in which the stage is driven by the other driver as the actuator body contracts in the longitudinal direction. FIG. 9 is a cross-sectional view corresponding to FIG. 8 when a foreign object enters between the driver and the stage. 6 is a perspective view showing an ultrasonic actuator according to Modification 1. FIG. 10 is a perspective view showing an ultrasonic actuator according to Modification 2. FIG. FIG. 9 is a cross-sectional view corresponding to FIG. 8 illustrating an ultrasonic actuator according to Modification 3. It is sectional drawing equivalent to FIG. 8 which shows the ultrasonic actuator which concerns on another modification. 5 is an exploded perspective view showing an ultrasonic actuator according to Embodiment 2. FIG. FIG. 9 is a cross-sectional view corresponding to FIG. 8 illustrating an ultrasonic actuator according to a second embodiment. It is sectional drawing equivalent to FIG. 8 which shows the ultrasonic actuator which concerns on a modification. It is a perspective view of the drive device concerning other embodiments. It is a perspective view of the drive device concerning other other embodiments. It is a perspective view of the drive device concerning other other embodiments.

1,401,501,601,701,801,901 Driving device 10 Base (base member)
11,411,511,611 Stage (contact member)
14,414,614 side surface (contacted surface)
14a, 414a, 614a, 714a, 814a First surface 14b, 414b, 614b, 714b, 814b Second surface 2, 202, 302, 402 Ultrasonic actuator 2A First ultrasonic actuator 2B Second ultrasonic actuator 4 Actuator body 5 Driver 6, 206, 306 Support spring (support member)
61, 261, 361 Flat surface (biasing portion)
64, 264, 364 Mounting portion 711 Stage (base member)
713 Contacted member 811, 911 Disc body (contacted member)
814 Side peripheral surface (contacted surface)
914 Flat surface (contacted surface)
P Circumference surface

Claims (8)

A vibration-type actuator; a base member to which the vibration-type actuator is attached; and a contacted member to which the vibration-type actuator comes into contact. The base member and the contacted member are driven by the driving force of the vibration-type actuator. A relatively moving drive device,
The vibration type actuator is configured by using a piezoelectric element to generate a plurality of vibrations having different vibration directions, and a surface provided on the actuator body and including the plurality of vibration directions according to the vibration of the actuator body. And a support member that supports the actuator body with respect to the base member in a state where the drive element is in contact with the contacted body. And
The support member is a drive device in which rigidity in a direction intersecting with a rotating surface on which the driver rotates is lower than rigidity in the drive direction. The drive device according to claim 1,
The contacted member is formed with a contacted surface with which the driving element contacts,
The driver and the abutted surface abut at at least two abutting portions,
A straight line connecting the two contact portions intersects the circumferential surface,
The drive device in which the tangent planes at the two contact portions intersect each other. The drive device according to claim 2, wherein
The drive device in which the contact surface is recessed inward of the contact member. The drive device according to claim 3, wherein
The contact surface includes a first surface and a second surface that intersect with each other so as to form a groove extending in a relative movement direction of the base member and the contact member,
The two contact portions are a drive device that is a contact portion between the driver element and the first surface and a contact portion between the driver element and the second surface. The drive device according to claim 2, wherein
The contacted surface bulges outward of the contacted member;
At least two of the driver elements are provided side by side in a direction intersecting the circumferential surface,
The two contact portions are a driving device that is a contact portion between one of the driver elements and the contacted surface and a contact portion between the other driver element and the contacted surface. The drive device according to claim 5, wherein
The abutted surface includes a first surface and a second surface intersecting each other so that an intersection line with a plane perpendicular to the relative movement direction of the base member and the abutted member has a mountain shape.
The two contact portions are drive devices that are a contact portion between one of the driver elements and the first surface and a contact portion between the other driver element and the second surface. The drive device according to any one of claims 1 to 6,
The support member includes a leaf spring in which a thickness direction faces a direction intersecting the circumferential surface. The drive device according to claim 7, wherein
The support member includes a plate-like urging portion that is joined to the actuator main body and urges the actuator main body toward the contacted member side, and bends and extends with respect to the urging portion to the base member. A leaf spring having a plate-like attachment portion to be attached,
The biasing portion is directed in a direction in which a thickness direction biases the actuator body,
The mounting portion is a drive device in which a thickness direction faces a direction intersecting the circumferential surface.

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