JP2010226895A - Actuator, driver, lens unit and imaging device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an actuator which has a second electrochemical conversion unit that extends/contracts, in a direction of crossing the direction of move of a mover, in a phase which is different from the phase of a first electrochemical conversion unit to collaborate with the first electrochemical conversion unit and causes a protrusion to rock in the direction of move of the mover while shifting toward the mover. <P>SOLUTION: The actuator moves the mover. The actuator includes the protrusion having a pair of legs which extends from a position distant from the mover, in a direction perpendicular to the direction of move of the mover toward the mover and is split in the direction of move of the mover by a slot formed to extend from an end at the far side to the mover toward the mover; the first electrochemical conversion unit which supports one of the pair of legs, and when supplied with power, extends/contracts in a direction crossing the direction of move of the mover, and the second electrochemical conversion unit which supports the other of the pair of legs and when supplied with power, extends/contracts in a direction crossing the direction of move of the mover in a phase different from the phase of the first electrochemical conversion unit to collaborate with the first electrochemical conversion unit and causes the protrusion to rock in the direction of move of the mover, while shifting toward the mover. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an actuator, a driving device, a lens unit, and an imaging device.

2. Description of the Related Art A vibration type driving device is known that includes an elastic vibration body provided with a protrusion and a pair of columnar support bodies that include an electro-mechanical energy conversion element and support the elastic vibration body (for example, Patent Document 1). reference). In the vibration type driving device, the protrusions are caused to elliptically move by expanding and contracting the pair of columnar supports in the axial direction with mutually different phases.
JP 2007-185056 A

  In the above vibration type driving device, both sides of the elastic vibration member sandwiching the base end portion of the protrusion are thin portions, and a gap is formed between the thin portion and the support. Here, the support point of the elastic vibrating body by the support body and the protrusion are separated. For this reason, the amount of relative displacement of the protrusion in the lateral direction with respect to the amount of expansion and contraction of the support decreases.

  In order to solve the above problems, as a first embodiment of the present invention, there is provided an actuator for moving a moving element from a position away from the moving element in a direction perpendicular to the moving direction of the moving element to the moving element. A protrusion having a pair of legs extending in a moving direction of the moving element by a groove provided on the moving element side from an end far from the moving element, and a pair of leg parts The first electromechanical converter that extends and contracts in a direction intersecting the moving direction of the moving element and the other of the pair of legs are supported and supplied with electric power. Thus, by extending and contracting with a phase different from that of the first electromechanical conversion unit in a direction intersecting with the moving direction of the moving element, in cooperation with the first electromechanical conversion unit, the projecting portion is While moving to the side of the mover, the mover A second electromechanical transducer unit is swung in the direction of movement, to provide an actuator comprising a.

  The summary of the invention described above does not enumerate all necessary features, and sub-combinations of these feature groups can also be the invention.

  Hereinafter, the present invention will be described through embodiments of the invention. However, the following embodiments do not limit the invention according to the scope of claims, and all combinations of features described in the embodiments are included. It is not necessarily essential for the solution of the invention.

  FIG. 1 is a perspective view illustrating a motor 10 including an actuator 100 according to an embodiment. For convenience of explanation, the drive output side in the axial direction of the rotating shaft 110 is referred to as an output side, and the opposite side is referred to as a non-output side. Further, the case where the motor 10 is viewed from the axial direction of the rotating shaft 110 (hereinafter referred to as the rotating shaft direction) will be described as a plan view, and the case where the motor 10 is viewed from the radial direction of the rotating shaft 110 will be described as a side view.

  As shown in this figure, the motor 10 includes a rotating shaft 110, a nut 210 arranged in order from the output side along the rotating shaft 110, a mounting plate 120, a biasing member 130, a washer 230, a rotor 140, and three actuators. 100, a base 190 and a nut 220. The mounting plate 120 is formed in a disk shape, and the rotating shaft 110 is inserted through the axis. Further, the mounting plate 120 is formed with a pair of U-shaped fastening holes 122 symmetrically with respect to the axis, and the mounting plate 120 is fastened by a fastener such as a screw inserted through the fastening hole 122. And fastened to a device that uses the motor 10 as a drive source.

  The rotor 140 is formed in a disk shape, and the rotating shaft 110 is inserted through the shaft center. A gear portion 144 is formed at the output side end of the rotor 140. An example of the urging member 130 is a compression coil spring shown in the figure, and the rotating shaft 110 is inserted therethrough. The actuator 100 includes a stator 150, a pair of electromechanical converters 160 and 162, a pair of flexible printed wiring boards 170 and 172, and a base 180.

  The base 180 is a rectangular plate-like member and is screwed to the base 190. The pair of electromechanical conversion units 160 and 162 are stacked piezoelectric elements in which piezoelectric elements are stacked in the rotation axis direction, and expand and contract in the stacking direction when a driving voltage is supplied. In addition, the pair of electromechanical conversion units 160 and 162 are arranged side by side in the longitudinal direction of the base 180. In addition, the pair of flexible printed wiring boards 170 and 172 are arranged side by side in the longitudinal direction of the base 180, and the flexible printed wiring board 170 is sandwiched between the base 180 and the electromechanical conversion unit 160, and the flexible printed wiring board 172. Is sandwiched between the base 180 and the electromechanical converter 162.

  The stator 150 is formed of an elastic material, and includes a rectangular plate-like base portion 152 and a protruding portion 154 that protrudes from a central portion in the longitudinal direction of the base portion 152. One end side in the longitudinal direction of the base portion 152 is joined to the upper end surface of the electromechanical conversion unit 160, and the other end side in the longitudinal direction of the base portion 152 is joined to the upper end surface of the electromechanical conversion unit 162. Further, the protrusion 154 protrudes from the base portion 152 toward the rotor 140.

  The flexible printed wiring board 170 supplies an alternating drive voltage to the electromechanical converter 160 to expand and contract the electromechanical converter 160 in the rotation axis direction. In addition, the flexible printed wiring board 172 supplies an alternating drive voltage to the electromechanical conversion unit 162 to expand and contract the electromechanical conversion unit 162 in the rotation axis direction.

  FIG. 2 is an exploded perspective view showing the motor 10. As shown in this figure, screw portions 112 into which nuts 210 and 220 are screwed are formed at both ends in the axial direction of the rotating shaft 110, and a disk-shaped flange portion 114 having an enlarged diameter is formed between them. It is formed. The nut 210, the mounting plate 120, the biasing member 130, the washer 230, and the rotor 140 are arranged on the output side with respect to the flange portion 114, while the base 190 and the nut 220 are on the non-output side with respect to the flange portion 114. Arranged. Further, the three actuators 100 are arranged between the rotor 140 and the base 190 so as to surround the rotating shaft 110. Further, the rotor 140 is rotatably supported by the rotating shaft 110 via the bearing 142.

  FIG. 3 is a side sectional view showing the motor 10. As shown in this figure, the mounting plate 120, the biasing member 130, the washer 230, the rotor 140, the actuator 100, and the base 190 are fastened in the direction of the rotation axis by nuts 210 and 220. Here, the urging member 130 is elastically contracted in the rotation axis direction, and the rotor 140 is pressed against the actuator 100 via the washer 230.

  4 is a cross-sectional view taken along line 4-4 of FIG. As shown in this figure, the three actuators 100 are arranged around the rotation axis 110 while being shifted by 2π / 3, and the space surrounded by these is a triangle in plan view. The three protrusions 154 are arranged around the rotation axis 110 while being shifted by 2π / 3.

  FIG. 5 is a perspective view showing the actuator 100. As shown in this figure, in the actuator 100, a gap 161 is provided between the pair of electromechanical conversion units 160 and 162, and the pair of electromechanical conversion units 160 and 162 are in a direction perpendicular to the expansion / contraction direction ( That is, they are separated in the arrangement direction.

  In addition, a rectangular groove 153 that bisects the base portion 152 in the longitudinal direction is formed at the longitudinal center portion of the base portion 152 of the stator 150. The groove 153 extends over the entire width direction of the base portion 152 and is formed so as to overlap with the gap 161 between the pair of electromechanical conversion portions 160 and 162 in the rotation axis direction. For this reason, the entire longitudinal end of the base portion 152 (hereinafter referred to as the base portion 1521) is joined to the entire end surface of the electromechanical transducer 160, and the longitudinal end of the base portion 152 (hereinafter referred to as the base portion). 1522) is joined to the entire end face of the electromechanical transducer 162.

  Further, the groove 153 extends through the base portion 152 to the base end portion of the protruding portion 154 in the depth direction. Thus, a pair of leg portions 156 and 157 that are divided into two in the longitudinal direction of the base portion 152 by the groove 153 are formed at the base end portion of the projection portion 154. The leg portion 156 extends from the end portion of the base portion 1521 on the groove 153 side to the opposite side of the electromechanical conversion portion 160. Further, the leg portion 157 extends from the end portion of the base portion 1522 on the groove 153 side to the opposite side of the electromechanical conversion portion 162. In other words, the protruding portion 154 is supported on the base portion 152 by a U-shaped base end portion including a pair of leg portions 156 and 157.

  In addition, a waveform shaper 175 is connected to the flexible printed wiring boards 170 and 172 via drivers 171 and 173, respectively. The driver 171 applies the drive voltage whose waveform is shaped by the waveform shaper 175 to the electromechanical converter 160. Further, the driver 173 applies the drive voltage whose waveform is shaped by the waveform shaper 175 to the electromechanical converter 162.

  Next, the operation in this embodiment will be described. FIG. 6A shows an outline of the operation of the stator 150. 6B shows the drive voltage waveform of the electromechanical converter 160 and the drive voltage waveform of the electromechanical converter 162.

  A waveform of an AC voltage (hereinafter referred to as an A-phase voltage) applied to the electromechanical conversion unit 160 indicated by a solid line in the graph is represented by sin θ. Moreover, the waveform of the alternating voltage (henceforth B phase voltage) applied to the electromechanical conversion part 162 shown with a broken line in a graph is represented by sin ((theta)-(pi) / 2). Hereinafter, the relationship between the change of the drive voltage of the electromechanical converter 160 and the electromechanical converter 162 and the operation of the stator 150 will be described in detail.

As shown in FIG. 6B, when θ = 0, the drive voltage applied to the electromechanical converter 160 is 0V, and the drive voltage applied to the electromechanical converter 162 is a negative maximum value (−V _MAX ). . In this state, the electromechanical conversion unit 160 does not expand and contract, and the electromechanical conversion unit 162 contracts to the maximum. For this reason, the projection part 154 takes the attitude | position which inclines to the electromechanical conversion part 162 side at the maximum.

At θ = π / 2, the drive voltage applied to the electromechanical conversion unit 160 is a positive maximum value (V _MAX ), and the drive voltage applied to the electromechanical conversion unit 162 is 0V. In this state, the electromechanical converter 160 extends to the maximum. On the other hand, the electromechanical converter 162 does not expand and contract. For this reason, the projection part 154 takes the attitude | position which inclines to the electromechanical conversion part 162 side at the maximum.

  Here, when transitioning from θ = 0 to θ = π / 2, the protrusion 154 is maintained in a posture inclined toward the electromechanical conversion unit 162 by the action of the electromechanical conversion units 160 and 162. Further, the protrusion 154 is displaced toward the rotor 140 when the electromechanical converters 160 and 162 both increase the extension amount.

Next, at θ = 3π / 4, the drive voltage applied to the electromechanical converters 160 and 162 becomes a positive equivalent value (V ₂ ). Here, the driving voltage _{V 2} is the intermediate value between 0V and _{V MAX.} In this state, the electromechanical converters 160 and 162 are extended by the same amount. For this reason, the projection part 154 takes a posture without inclination.

  Here, when transitioning from θ = π / 2 to 3π / 4, the protrusion 154 changes from the posture inclined toward the electromechanical conversion unit 162 to the posture without inclination by the action of the electromechanical conversion units 160 and 162. Change. On the other hand, the protrusion 154 is displaced to the position closest to the rotor 140 (hereinafter referred to as the highest position) when the extension amount of the electromechanical conversion unit 162 exceeds the contraction amount of the electromechanical conversion unit 160.

Next, at θ = π, the drive voltage applied to the electromechanical conversion unit 160 is 0 V, and the drive voltage applied to the electromechanical conversion unit 162 is a positive maximum value (V _MAX ). In this state, the electromechanical conversion unit 160 does not expand and contract. On the other hand, the electromechanical converter 162 extends to the maximum. For this reason, the projection part 154 takes the attitude | position which inclines to the electromechanical conversion part 160 side at the maximum.

  Here, when transitioning from θ = 3π / 4 to θ = π, the projecting portion 154 is changed from a posture without inclination to a posture inclined toward the electromechanical conversion portion 160 by the action of the electromechanical conversion portions 160 and 162. Transition. On the other hand, the protrusion 154 is displaced from the uppermost position to the intermediate position when the contraction amount of the electromechanical conversion unit 160 exceeds the expansion amount of the electromechanical conversion unit 162.

Then, the θ = 3π / 2, the driving voltage _{-V MAX} becomes applied to the electromechanical conversion unit 160, the drive voltage applied to the electromechanical conversion unit 162 becomes 0V. In this state, the electromechanical conversion unit 160 contracts to the maximum. On the other hand, the electromechanical converter 162 does not expand and contract. For this reason, the projection part 154 takes the attitude | position which inclines to the electromechanical conversion part 160 side at the maximum.

  Here, when transitioning from θ = π to θ = 3π / 2, the protrusion 154 is maintained in a posture inclined toward the electromechanical conversion unit 160 by the action of the electromechanical conversion units 160 and 162. On the other hand, the projecting portion 154 is displaced from the intermediate position on the positive side to the intermediate position on the negative side by contracting the electromechanical converters 160 and 162 by the same amount.

Next, at θ = 7π / 4, the drive voltage applied to the electromechanical converters 160 and 162 becomes the negative negative value (−V ₂ ). Here, the drive voltage (−V ₂ ) is an intermediate value between 0V and −V _MAX . In this state, the electromechanical converters 160 and 162 are contracted by the same amount. For this reason, the projection part 154 takes a posture without inclination.

  Here, when transitioning from θ = 3π / 2 to 7π / 4, the protrusion 154 is changed from the posture inclined toward the electromechanical conversion unit 160 to the posture without inclination by the action of the electromechanical conversion units 160 and 162. Change. On the other hand, when the contraction amount of the electromechanical conversion unit 162 exceeds the extension amount of the electromechanical conversion unit 160, the protrusion 154 is displaced from the negative intermediate position to the lowest position.

  When the transition is made from θ = 7π / 4 to θ = 2π, the protrusion 154 returns to the state of θ = 0 described above.

  Here, the tip of the protrusion 154 is raised from the intermediate position in the axial direction to the highest position by the action of the electromechanical converters 160 and 162, and from the electromechanical converter 162 side to the electromechanical converter 160 side. Swing to. And the front-end | tip part of the projection part 154 moves from the electromechanical conversion part 162 side to the electromechanical conversion part 160 side, descend | falling from the highest position of an axial direction to an intermediate position by the effect | action of the electromechanical conversion parts 160 and 162. Swing.

  And the front-end | tip part of the projection part 154 moves from the electromechanical conversion part 160 side to the electromechanical conversion part 162 side, descend | falling to the lowest position from the intermediate position of an axial direction by the effect | action of the electromechanical conversion parts 160 and 162. Swing. The tip portion of the protrusion 154 rises from the lowest position in the axial direction to the intermediate position in the axial direction by the action of the electromechanical conversion portions 160 and 162, and from the electromechanical conversion portion 160 side to the electromechanical conversion portion 162. Swing to the side.

  That is, the tip of the protrusion 154 performs an elliptical motion that circulates around an axis along the radial direction of the rotor 140 by the action of the electromechanical converters 160 and 162.

  For this reason, the thrust from the electromechanical converter 162 side to the electromechanical converter 160 side is generated in the rotor 140 by the tip of the protrusion 154 moving from the electromechanical converter 162 side to the electromechanical converter 160 side. Is done. On the other hand, depending on the tip of the protrusion 154 moving from the electromechanical conversion unit 160 side to the electromechanical conversion unit 162 side, the thrust from the electromechanical conversion unit 160 side to the electromechanical conversion unit 162 side may be applied to the rotor 140. Not generated. In addition, drive voltages having the same phase waveform are applied to the electromechanical converter 160 and the electromechanical converter 162 of the three actuators 100, respectively. Therefore, the plurality of protrusions 154 that synchronize with each other in the above-described elliptical motion generate a rotational force in one direction on the rotor 140, and a rotational torque is output from the motor 10.

  FIG. 7 is a side view showing the operation of the stator 150. As shown in this figure, a base portion 1521 on one end side in the longitudinal direction of the base portion 152 and a base portion 1522 on the other end side in the longitudinal direction of the base portion 152 are separated by a groove 153. For this reason, as shown by a broken line in the figure, the base portion 1521 and the base portion 1522 can be independently displaced in the rotation axis direction, and the relative positions in the rotation axis direction can be made different.

  For example, as indicated by a broken line in the figure, the base portion 1521 can be displaced toward the rotor 140, while the base portion 1522 can be displaced toward the electromechanical conversion portion 160. In this case, the leg portion 156 integrated with the base portion 1521 is displaced toward the rotor 140, while the leg portion 157 integrated with the base portion 1522 is displaced toward the electromechanical conversion portion 160. As a result, the protrusion 154 is inclined toward the electromechanical converter 162.

  When the base portion 1522 is displaced toward the rotor 140 while the base portion 1521 is displaced toward the electromechanical conversion portion 162, the leg portion 157 is displaced toward the rotor 140 while the leg portion 156 is displaced. Displacement to the electromechanical converter 162 side. As a result, the protrusion 154 is inclined toward the electromechanical conversion unit 160.

  Here, a pair of legs 156 and 157 branched in the rotation direction of the rotor 140 by the groove 153 are provided at the base end of the protrusion 154, and the one leg 156 is supported by the electromechanical converter 160 and the other The leg portion 157 was supported by the electromechanical converter 162. Thereby, the amount of displacement equal to the amount of expansion / contraction of the electromechanical converter 160 is given to the leg 156 constituting one side in the rotation direction at the base end of the protrusion 154, and at the base end of the protrusion 154. The same amount of displacement as the amount of expansion / contraction of the electromechanical converter 162 can be applied to the leg 157 constituting the other side in the rotational direction. Therefore, the relative displacement amount in the direction along the rotation direction of the protrusion 154 with respect to the expansion / contraction amount of the electromechanical conversion units 160 and 162 can be efficiently expanded, and the output of the actuator 100 can be efficiently expanded. Can do.

  Further, the protrusion 154 is supported by the end of the electromechanical converter 160 on the electromechanical converter 162 side and the end of the electromechanical converter 162 on the electromechanical converter 160 side. Therefore, the relative displacement amount in the direction along the rotation direction of the protrusion 154 with respect to the expansion / contraction amount of the electromechanical conversion units 160 and 162 can be increased more efficiently, and the output of the actuator 100 can be further improved. Can be magnified well.

  The motor 10 according to the present embodiment includes three actuators 200, but the number of actuators 200 may be two or more than three. Further, it may be singular.

  Moreover, in the motor 10, although the projection part 154 was circularly moved, it may be moved along a rectangular path | route and may be reciprocated. When the protrusion 154 is reciprocated, the rotor 140 can continue to rotate in one direction by making the moving speed of the rotor 140 in the rotating direction slower than the moving speed in the counter-rotating direction.

  FIG. 8 is a perspective view showing a motor 20 including an actuator 200 according to another embodiment. As shown in this figure, the actuator 200 includes a stator 150, a pair of electromechanical transducers 160, 162, a pair of flexible printed wiring boards 170, 172, a base 260, an electromechanical transducer 240, and a flexible printed wiring board. 250 and a base 180.

  The base 260 is a rectangular plate material, and supports a pair of electromechanical converters 160 and 162 arranged side by side in the longitudinal direction of the base 260. In addition, the pair of flexible printed wiring boards 170 and 172 are arranged side by side in the longitudinal direction of the base 260. The flexible printed wiring board 170 is sandwiched between the electromechanical converter 160 and the base 260, and the flexible printed wiring board 172 is sandwiched between the electromechanical converter 162 and the base 260.

  Further, the electromechanical converter 240 and the flexible printed wiring board 250 are sandwiched between the base 260 and the base 180. The flexible printed wiring board 250 supplies an AC drive voltage to the electromechanical converter 240 to expand and contract the electromechanical converter 240 in the rotation axis direction.

  FIG. 9 is an exploded perspective view showing the motor 20. As shown in this figure, the three actuators 200 are arranged between the rotor 140 and the base 190 so as to surround the rotating shaft 110.

  FIG. 10 is a side sectional view showing the motor 20. As shown in this figure, the mounting plate 120, the biasing member 130, the rotor 140, the actuator 200, and the base 190 are tightened in the rotation axis direction by nuts 210 and 220. Here, the biasing member 130 is elastically contracted in the direction of the rotation axis, and presses the rotor 140 against the actuator 100.

  FIG. 11 is a perspective view showing the actuator 200. As shown in this figure, in the actuator 200, a pair of electromechanical transducers 160 and 162 arranged in the rotational direction and an electromechanical transducer 240 are arranged so as to overlap in the rotational axis direction.

  Next, the operation in this embodiment will be described. FIG. 12A shows an outline of the operation of the stator 150. 12B shows the drive voltage waveforms of the electromechanical converters 160 and 162 and the drive voltage waveform of the electromechanical converter 240.

  The waveform of the alternating voltage applied to the electromechanical converter 160 indicated by a solid line in the upper graph is represented by sin θ. Moreover, the waveform of the alternating voltage applied to the electromechanical conversion unit 162 indicated by a broken line in the upper graph is represented by sin (θ−π / 2). Moreover, the waveform of the alternating voltage applied to the electromechanical conversion unit 240 indicated by a chain line in the lower graph is represented by sin (θ−π / 4). Hereinafter, the relationship between the change in the driving voltage of the electromechanical converters 160, 162, and 240 and the operation of the stator 150 will be described in detail.

As shown in FIG. 12B, when θ = 0, the drive voltage applied to the electromechanical conversion unit 160 is 0 V, and the drive voltage applied to the electromechanical conversion unit 162 is a negative maximum value (−V _MAX ). . In this state, the electromechanical conversion unit 160 does not expand and contract, and the electromechanical conversion unit 162 contracts to the maximum. For this reason, the projection part 154 takes the attitude | position which inclines to the electromechanical conversion part 162 side at the maximum.

Further, when θ = 0, the drive voltage applied to the electromechanical converter 240 is an intermediate value (−V ₁ ) between 0 V and −V _MAX . In this state, the entire electromechanical conversion unit 240 is contracted. Note that the amount of contraction of the electromechanical converter 240 in this state is smaller than the maximum amount of contraction.

At θ = π / 2, the drive voltage applied to the electromechanical conversion unit 160 is a positive maximum value (V _MAX ), and the drive voltage applied to the electromechanical conversion unit 162 is 0V. In this state, the electromechanical converter 160 extends to the maximum. On the other hand, the electromechanical converter 162 does not expand or contract. For this reason, the projection part 154 takes the attitude | position which inclines to the electromechanical conversion part 162 side at the maximum.

Further, when θ = π / 2, the drive voltage applied to the electrode of the electromechanical conversion unit 240 is an intermediate value (V ₁ ) between 0 V and V _MAX . In this state, the entire electromechanical converter 240 is extended. In this state, the extension amount of the electromechanical conversion unit 240 is smaller than the maximum extension amount.

  Here, when transitioning from θ = 0 to θ = π / 2, the protrusion 154 is maintained in a posture inclined toward the electromechanical conversion unit 162 by the action of the electromechanical conversion units 160 and 162. Further, the protrusion 154 is displaced toward the rotor 140 when the electromechanical converters 160 and 162 both increase the extension amount. Furthermore, the protrusion 154 is displaced more greatly toward the rotor 140 when the electromechanical converter 240 changes from the contracted state to the extended state.

Next, at θ = 3π / 4, the drive voltage applied to the electromechanical converters 160 and 162 becomes a positive equivalent value (V ₂ ). Here, the driving voltage _{V 2} is the intermediate value between 0V and _{V MAX.} In this state, the electromechanical conversion unit 160 and the electromechanical conversion unit 162 expand by the same amount. For this reason, the projection part 154 takes a posture without inclination.

In addition, at θ = 3π / 4, the drive voltage applied to the electrode of the electromechanical conversion unit 240 becomes the maximum value (V _MAX ). In this state, the entire extension amount of the electromechanical conversion unit 240 is maximized.

  Here, when transitioning from θ = π / 2 to 3π / 4, the protrusion 154 changes from the posture inclined toward the electromechanical conversion unit 162 to the posture without inclination by the action of the electromechanical conversion units 160 and 162. Change. Further, when the extension amount of the electromechanical conversion unit 162 exceeds the contraction amount of the electromechanical conversion unit 160, the protrusion 154 is displaced to the position closest to the rotor 140 (hereinafter referred to as the highest level). Further, the protrusion 154 is displaced more greatly toward the rotor 140 as the extension amount of the electromechanical conversion unit 240 increases to the maximum amount.

Next, at θ = π, the drive voltage applied to the electromechanical conversion unit 160 is 0 V, and the drive voltage applied to the electromechanical conversion unit 162 is a positive maximum value (V _MAX ). In this state, the electromechanical conversion unit 160 does not expand or contract. On the other hand, the electromechanical converter 162 extends to the maximum. For this reason, the projection part 154 takes the attitude | position which inclines to the electromechanical conversion part 160 side at the maximum.

In addition, at θ = π, the drive voltage applied to the electrode of the electromechanical conversion unit 240 becomes a positive intermediate value (V ₁ ). In this state, the entire extension amount of the electromechanical conversion unit 240 is smaller than the maximum extension amount.

  Here, when transitioning from θ = 3π / 4 to θ = π, the projecting portion 154 is changed from a posture without inclination to a posture inclined toward the electromechanical conversion portion 160 by the action of the electromechanical conversion portions 160 and 162. Transition. Further, the protrusion 154 is displaced from the uppermost position to the intermediate position when the contraction amount of the electromechanical conversion unit 160 exceeds the expansion amount of the electromechanical conversion unit 162. Further, the protrusion 154 is displaced more to the opposite side of the rotor 140 as the extension amount of the electromechanical conversion unit 240 decreases from the maximum amount.

Next, at θ = 3π / 2, the drive voltage applied to the electromechanical conversion unit 160 is −V _MAX , and the drive voltage applied to the electromechanical conversion unit 162 is 0V. In this state, the electromechanical conversion unit 160 contracts to the maximum. On the other hand, the electromechanical converter 162 does not expand and contract. For this reason, the projection part 154 takes the attitude | position which inclines to the electromechanical conversion part 160 side at the maximum.

In addition, at θ = 3π / 2, the drive voltage applied to the electrode of the electromechanical conversion unit 240 becomes a negative intermediate value (−V ₁ ). In this state, the total contraction amount of the electromechanical conversion unit 240 is smaller than the maximum contraction amount.

  Here, when transitioning from θ = π to θ = 3π / 2, the protrusion 154 is maintained in a posture inclined toward the electromechanical conversion unit 160 by the action of the electromechanical conversion units 160 and 162. Further, the projecting portion 154 is displaced from the intermediate position on the positive side to the intermediate position on the negative side when the electromechanical converters 160 and 162 contract by the same amount. Furthermore, the protrusion 154 is displaced more greatly to the opposite side of the rotor 140 when the electromechanical conversion unit 240 transitions from the extended state to the contracted state.

Next, at θ = 7π / 4, the drive voltage applied to the electromechanical conversion unit 160 has a negative equivalent value (−V ₂ ). Here, the drive voltage (−V ₂ ) is an intermediate value between 0V and −V _MAX . In this state, the electromechanical conversion unit 160 and the electromechanical conversion unit 162 contract by the same amount. For this reason, the projection part 154 takes a posture without inclination.

In addition, when θ = 7π / 4, the drive voltage applied to the electrode of the electromechanical conversion unit 240 has a negative maximum value (−V _MAX ). In this state, the entire contraction amount of the electromechanical converter 240 is maximized.

  Here, when transitioning from θ = 3π / 2 to 7π / 4, the protrusion 154 is changed from the posture inclined toward the electromechanical conversion unit 160 to the posture without inclination by the action of the electromechanical conversion units 160 and 162. Change. Further, the protrusion 154 is displaced from the intermediate position on the negative side to the lowest position when the contraction amount of the electromechanical conversion unit 162 exceeds the expansion amount of the electromechanical conversion unit 160. Further, the protrusion 154 is more displaced to the opposite side of the rotor 140 as the contraction amount of the electromechanical conversion unit 240 increases to the maximum amount.

  When the transition is made from θ = 7π / 4 to θ = 2π, the protrusion 154 returns to the state of θ = 0 described above.

  Here, the tip of the protrusion 154 is raised from the intermediate position in the axial direction to the highest position by the action of the electromechanical converters 160 and 162, and from the electromechanical converter 162 side to the electromechanical converter 160 side. Swing to. And the front-end | tip part of the projection part 154 moves from the electromechanical conversion part 162 side to the electromechanical conversion part 160 side, descend | falling from the highest position of an axial direction to an intermediate position by the effect | action of the electromechanical conversion parts 160 and 162. Swing.

  And the front-end | tip part of the projection part 154 moves from the electromechanical conversion part 160 side to the electromechanical conversion part 162 side, descend | falling to the lowest position from the intermediate position of an axial direction by the effect | action of the electromechanical conversion parts 160 and 162. Swing. The tip portion of the protrusion 154 rises from the lowest position in the axial direction to the intermediate position in the axial direction by the action of the electromechanical conversion portions 160 and 162, and from the electromechanical conversion portion 160 side to the electromechanical conversion portion 162. Swing to the side.

  That is, the tip of the protrusion 154 performs an elliptical motion that circulates around an axis along the radial direction of the rotor 140 by the action of the electromechanical converters 160 and 162.

  Further, the protrusion 154 reciprocates in the direction approaching or separating from the rotor 140 by the action of the electromechanical converter 240. Here, the electromechanical conversion unit 240 extends as the tip of the protrusion 154 moves along an elliptical arc that swells from the electromechanical conversion unit 162 side to the electromechanical conversion unit 160 side toward the rotor 140 side. Then, the protrusion 154 is raised. In addition, the electromechanical converter 240 contracts as the tip of the protrusion 154 moves along an elliptical arc that swells from the electromechanical converter 160 side to the electromechanical converter 162 side on the opposite side of the rotor 140. Then, the protrusion 154 is lowered.

  For this reason, the rotor 140 has a thrust from the electromechanical conversion unit 162 side to the electromechanical conversion unit 160 side by the tip of the projection 154 moving from the electromechanical conversion unit 162 side to the electromechanical conversion unit 160 side. Is generated. On the other hand, depending on the tip of the protrusion 154 moving from the electromechanical conversion unit 160 side to the electromechanical conversion unit 162 side, the rotor 140 may be moved from the electromechanical conversion unit 160 side to the electromechanical conversion unit 162 side. No thrust is generated. Accordingly, the plurality of protrusions 154 that perform the elliptical motion synchronously generate a rotational force in one direction on the rotor 140, and a rotational torque is output from the motor 20.

  Here, since the electromechanical converters 160 and 162 cause the protrusions 154 to make an elliptical motion around the axis along the radial direction of the rotor 140, even if the electromechanical converter 240 is not provided. The rotor 140 can generate a rotational force in one direction. However, since the electromechanical converter 240 that exhibits the above-described action is provided, the amount of movement of the protrusion 154 in the rotation axis direction can be amplified. Therefore, the kinetic energy transmitted from the protrusion 154 to the rotor 140 can be increased efficiently, the thrust generated in the rotor 140 can be increased efficiently, and the output torque can be increased efficiently.

  Further, since the whole of the electromechanical conversion unit 240 in the circumferential direction expands and contracts in the axial direction, the amount of expansion and contraction in the axial direction of the electromechanical conversion unit 240 can be increased efficiently, and the amount of movement of the protrusion 154 in the rotation axis direction. Can be increased efficiently. Further, as the amount of movement of the protrusion 154 in the rotation axis direction can be increased efficiently, the kinetic energy is efficiently transmitted from the protrusion 154 to the rotor 140 when the protrusion 154 moves along the rotation direction of the rotor 140. On the other hand, when the protrusion 154 moves in the direction opposite to the rotation direction of the rotor 140, the kinetic energy transmitted from the protrusion 154 to the rotor 140 is effectively reduced.

  In addition, the output torque can be increased efficiently, and in order to obtain the same output torque, the number of piezoelectric material plates constituting the electromechanical converters 160, 162, 240 can be reduced or the area can be reduced. it can. Therefore, the electromechanical conversion units 160, 162, and 240 can be reduced in size, and thus the actuator 200 can be reduced in size. Moreover, since the drive voltage of the electromechanical converters 160, 162, and 240 can be lowered to obtain the same output torque, the power consumption can be reduced.

  Further, by superimposing the outputs of the electromechanical conversion units 160 and 162 and the electromechanical conversion unit 240, the amount of displacement of the protrusion 154 can be increased. Therefore, even if the resonance of the entire system is not used, a sufficient rotational force can be generated in the rotor 140. Thereby, the design freedom about the shape and dimension of the motor 20 increases. Further, when resonance is not used, the frequency of the voltage applied to the electromechanical converters 160, 162, and 240 can be varied, so that the rotational speed of the rotor 140 can be controlled by the frequency of the voltage.

  Next, another operation method of the motor 20 will be described. FIG. 13A shows an outline of the operation of the stator 150. 13B shows the drive voltage waveform of the electromechanical converters 160 and 162 and the drive voltage waveform of the electromechanical converter 240. The waveform of the alternating voltage applied to the electromechanical converter 160 indicated by a solid line in the upper graph is represented by sin θ. Moreover, the waveform of the alternating voltage applied to the electromechanical conversion part 162 shown with a broken line in a graph is represented by sin ((theta)-(pi)). Furthermore, the waveform of the alternating voltage applied to the electromechanical conversion unit 240 indicated by a chain line in the lower graph is represented by cos θ. Hereinafter, the relationship between the change of the drive voltage of the electromechanical converter 160 and the electromechanical converter 162 and the operation of the stator 150 will be described in detail. Hereinafter, the relationship between the change in the driving voltage of the electromechanical converters 160, 162, and 240 and the operation of the stator 150 will be described in detail.

  As shown in FIG. 13B, when the drive voltage of the electromechanical converter 240 is maximized on the positive side, the drive voltages of the electromechanical converters 160 and 162 are 0V. In this state, the protrusion 154 takes a posture with no inclination at the position closest to the rotor 140 (hereinafter referred to as the highest position). From this state, the drive voltage of the electromechanical converter 240 is decreased, the drive voltage applied to the electromechanical converter 160 is decreased, and the drive voltage applied to the electromechanical converter 162 is increased. . When the drive voltage of the electromechanical converter 240 is reduced to 0V, the drive voltage applied to the electromechanical converter 160 is maximized on the negative side, and the drive voltage applied to the electromechanical converter 162 is on the positive side. Maximum. In this state, the protrusion 154 is inclined to the maximum at the electromechanical conversion unit 160 side at an intermediate position of the movable range in the axial direction (hereinafter referred to as an intermediate position).

  From this state, the drive voltage of the electromechanical converter 240 is decreased, the drive voltage applied to the electromechanical converter 160 is increased, and the drive voltage applied to the electromechanical converter 162 is decreased. When the drive voltage of the electromechanical converter 240 becomes maximum on the negative side, the drive voltage applied to the electromechanical converters 160 and 162 becomes 0V. In this state, the projecting portion 154 takes a posture with no inclination at a position on the most opposite side of the rotor 140 (hereinafter referred to as the lowest position).

  From this state, the drive voltage of the electromechanical converter 240 is increased, the drive voltage applied to the electromechanical converter 160 is increased, and the drive voltage applied to the electromechanical converter 162 is decreased. When the drive voltage of the electromechanical converter 240 becomes 0V, the drive voltage applied to the electromechanical converter 160 is maximum on the positive side, and the drive voltage applied to the electromechanical converter 162 is maximum on the negative side. Become. In this state, the protrusion 154 is inclined to the electromechanical conversion unit 162 side at the intermediate position.

  From this state, the drive voltage of the electromechanical converter 240 is increased, the drive voltage applied to the electromechanical converter 160 is decreased, and the drive voltage applied to the electromechanical converter 162 is increased. When the drive voltage of the electromechanical converter 240 is maximized, the drive voltage applied to the electromechanical converters 160 and 162 is 0V. In this state, the projecting portion 154 takes a posture with no inclination at the highest position.

  That is, the protrusion 154 changes from an attitude inclined toward the electromechanical converter 162 side to an attitude inclined toward the electromechanical converter 160 until it rises from the intermediate position to the highest position and descends to the intermediate position. . At this time, the reciprocating motion along the axial direction between the intermediate position and the highest position of the protrusion 154 and the movement of the protrusion 154 from the electromechanical converter 162 side to the electromechanical converter 160 side are superimposed. The As a result, the tip of the protrusion 154 moves from the electromechanical converter 162 side to the electromechanical converter 160 side while drawing an elliptical arc that swells to the rotor 140 side.

  Further, the protrusion 154 transitions from a posture inclined toward the electromechanical conversion unit 160 side to a posture inclined toward the electromechanical conversion unit 162 until the protrusion 154 descends from the intermediate position to the lowest position and rises to the intermediate position. . At this time, the reciprocating motion along the axial direction between the intermediate position and the lowest position of the protrusion 154 and the movement of the protrusion 154 from the electromechanical converter 160 side to the electromechanical converter 162 side are superimposed. The As a result, the tip of the protrusion 154 moves from the electromechanical converter 160 side to the electromechanical converter 162 side while drawing an elliptical arc that swells on the opposite side of the rotor 140.

  That is, the tip of the protrusion 154 performs an elliptical motion that circulates around an axis along the radial direction of the rotor 140. For this reason, the thrust from the electromechanical converter 162 side to the electromechanical converter 160 side is generated in the rotor 140 by the tip of the protrusion 154 moving from the electromechanical converter 162 side to the electromechanical converter 160 side. Is done. On the other hand, the thrust from the electromechanical converter 160 side to the electromechanical converter 162 side is generated in the rotor 140 by the tip of the protrusion 154 moving from the electromechanical converter 160 side to the electromechanical converter 162 side. Not. Therefore, the plurality of protrusions 154 that synchronize with each other in the elliptical manner generate a rotational force in one direction on the rotor 140 and output a rotational torque.

  In the present embodiment, the tip of the protrusion 154 has an elliptical motion with the rotation direction as the major axis as an example of a circular motion, but as an example of another circular motion, The amount of expansion and contraction in the rotation axis direction may be increased so that the movement locus of the tip of the projection 154 is a perfect circle or an ellipse having the rotation axis direction as a major axis. That is, the tip of the protrusion 154 may be moved in a perfect circular motion or an elliptical motion with the rotation axis direction as the major axis.

  In the present embodiment, the amount of movement of the protrusion 154 in the rotation axis direction is the amount of expansion and contraction in the rotation axis direction of the region overlapped with the electromechanical conversion unit 160 or the electromechanical conversion unit 162, and the circumferential direction of the electromechanical conversion unit 240. This is an amount obtained by adding the amount of expansion / contraction in the direction of the rotation axis. Therefore, the kinetic energy transmitted from the protrusion 154 to the rotor 140 can be increased efficiently, the thrust generated in the rotor 140 can be increased efficiently, and the output torque can be increased efficiently.

  Further, since the whole of the electromechanical conversion unit 240 in the circumferential direction expands and contracts in the axial direction, the amount of expansion and contraction in the axial direction of the electromechanical conversion unit 240 can be increased efficiently, and the amount of movement of the protrusion 154 in the rotation axis direction. Can be increased efficiently. Further, as the amount of movement of the protrusion 154 in the rotation axis direction can be increased efficiently, the kinetic energy is efficiently transmitted from the protrusion 154 to the rotor 140 when the protrusion 154 moves along the rotation direction of the rotor 140. On the other hand, when the protrusion 154 moves in the direction opposite to the rotation direction of the rotor 140, the kinetic energy transmitted from the protrusion 154 to the rotor 140 is effectively reduced.

  In addition, the output torque can be increased efficiently, and in order to obtain the same output torque, the number of piezoelectric material plates constituting the electromechanical converters 160, 162, 240 can be reduced or the area can be reduced. it can. Therefore, the electromechanical conversion units 160, 162, and 240 can be reduced in size, and thus the actuator 200 can be reduced in size. Moreover, since the drive voltage of the electromechanical converters 160, 162, and 240 can be lowered to obtain the same output torque, the power consumption can be reduced.

  In addition, since the outputs of the electromechanical conversion units 160 and 162 and the electromechanical conversion unit 240 are superimposed, the amount of displacement of the protrusion 154 is large. Therefore, even if the resonance of the entire system is not used, the protrusion 154 can be greatly displaced, and a sufficient rotational force can be generated in the rotor 140. Thereby, the design freedom about the shape and dimension of the motor 20 increases. Further, when resonance is not used, the frequency of the voltage applied to the electromechanical converters 160, 162, and 240 can be varied, so that the rotational speed of the rotor 140 can be controlled by the frequency of the voltage.

  FIG. 14 is a plan view showing an embodiment in which four actuators 100 are arranged at intervals of π / 2 in the rotation direction. As shown in this figure, in this embodiment, four protrusions 154 are arranged at intervals of π / 2 in the rotation direction.

  Next, the operation of this embodiment will be described. FIG. 15A shows an outline of the operation of the stator 150. 15B shows the drive voltage waveform of the electromechanical converters 160 and 162 and the drive voltage waveform of the electromechanical converter 240. Hereinafter, the relationship between the change in the driving voltage of the electromechanical converters 160, 162, and 240 and the operation of the stator 150 will be described in detail.

  In this embodiment, the four actuators 100 are divided into two groups of actuators 100 each consisting of two actuators 100, and the two groups of actuators 100 are driven by drive signals having different phases. The upper part of FIG. 15A shows the operation of one of the two groups of actuators 100 (hereinafter referred to as the first group). The lower part of FIG. 15B shows the operation of the stator 150 of the other group (hereinafter referred to as the second group) of the two sets of actuators 100.

  The waveform of the AC voltage applied to the first group of electromechanical transducers 160 indicated by the solid line in the first graph from the top in FIG. 15B is represented by sin θ. Further, the waveform of the alternating voltage applied to the first group of electromechanical transducers 162 indicated by a broken line in the graph is represented by sin (θ−π / 2). In addition, the waveform of the alternating voltage applied to the first group of electromechanical transducers 240 indicated by a chain line in the third graph from the top is represented by sin (θ−π / 4).

  That is, the waveform of the AC voltage applied to the first group of electromechanical conversion units 160 is the same as the waveform of the AC voltage applied to the electromechanical conversion unit 160 indicated by a solid line in the upper graph of FIG. 12B. Moreover, the waveform of the alternating voltage applied to the electromechanical converter 162 of the first group is the same as the waveform of the alternating voltage applied to the electromechanical converter 162 indicated by a broken line in the upper graph of FIG. 12B. Furthermore, the waveform of the AC voltage applied to the first group of electromechanical converters 240 is the same as the waveform of the AC voltage applied to the electromechanical converter 240 indicated by the chain line in the lower graph of FIG. 12B. Therefore, the circular motion of the first group of stators 150 shown in the upper part of FIG. 15A has the same period and phase as the circular motion of the stator 150 shown in FIG. 12A.

  On the other hand, the waveform of the AC voltage applied to the second group of electromechanical transducers 160 indicated by the solid line in the second graph from the top in FIG. 15B is represented by sin (θ−π). In addition, the waveform of the alternating voltage applied to the second group of electromechanical transducers 162 indicated by a broken line in the graph is represented by sin (θ-3π / 2). In addition, the waveform of the AC voltage applied to the second group of electromechanical converters 240 indicated by a chain line in the fourth graph from the top is represented by sin (θ-5π / 4).

  That is, the waveform of the AC voltage applied to the second group of electromechanical converters 160 is out of phase by −π with respect to the waveform of the AC voltage applied to the first group of electromechanical converters 160. In addition, the waveform of the AC voltage applied to the second group of electromechanical converters 162 is out of phase by −π with respect to the waveform of the AC voltage applied to the first group of electromechanical converters 160. Further, the waveform of the AC voltage applied to the second group of electromechanical converters 240 is out of phase by −π with respect to the waveform of the AC voltage applied to the second group of electromechanical converters 240. Therefore, the circular motion of the second group of stators 150 shown in the lower part of FIG. 15A has the same period as the circular movement of the first group of stators 150 shown in the upper part of FIG.

  As a result, while the first group of protrusions 154 are moving along the elliptical arc swelled toward the rotor 140 from the electromechanical converter 162 side to the electromechanical converter 160 side, the second group of protrusions 154 154 moves along an elliptical arc that swells on the opposite side of the rotor 140 from the electromechanical converter 160 side to the electromechanical converter 162 side. While the first group of protrusions 154 are moving along the elliptical arc that swells from the electromechanical converter 160 side to the electromechanical converter 162 side on the opposite side of the rotor 140, the second group of protrusions 154 154 moves along an elliptical arc that swells toward the rotor 140 from the electromechanical converter 162 side to the electromechanical converter 160 side.

  That is, the first group of protrusions 154 and the second group of protrusions 154 alternately abut against the rotor 140 and apply thrust to the rotor 140. Thereby, compared with the case where the four protrusions 154 are circularly moved in the same phase, the time during which the thrust does not act on the rotor 140 from the protrusions 154 can be shortened. The thrust can be applied more continuously.

  Here, in this embodiment, the pair of protrusions 154 arranged symmetrically with respect to the rotation shaft 110 are moved in synchronization. Thereby, the symmetry with respect to the rotation center of the thrust acting on the rotor 140 can be increased, and the torsional moment acting on the rotating shaft 110 can be reduced.

  In this embodiment, four actuators 200 are arranged. However, the number of actuators 200 may be plural, and if at least one of the actuators 200 is circularly moved in a phase different from that of the other actuators 200, Good. In the present embodiment, the actuator 200 is used, but the actuator 100 may be used.

  FIG. 16 is a front view showing an actuator 600 according to another embodiment. As shown in this figure, in the actuator 600, a groove 602 is formed along a corner portion that is a boundary portion between the leg portion 156 and the base portion 1521, and a corner portion that is a boundary portion between the leg portion 157 and the base portion 1522 is formed. A groove 604 is formed along the line. Further, a groove 606 is formed along a corner that is a boundary between the protrusion 154 and the leg 156, and a groove 608 is formed along a corner that is a boundary between the protrusion 154 and the leg 157. Yes.

  For this reason, the boundary part of the leg part 156 and the base part 1521 and the boundary part of the leg part 157 and the base part 1522 are thinner than the leg parts 156 and 157, and the rigidity in the said part is reduced. Moreover, the boundary part of the projection part 154 and the leg part 156 and the boundary part of the projection part 154 and the leg part 157 are thinner than the leg parts 156 and 157, and the rigidity in the said part is reduced.

  Thereby, the flexibility in the boundary part of the leg part 156 and the base part 1521, the boundary part of the leg part 157 and the base part 1522, and the boundary part of the projection part 154 and the leg parts 156 and 157 is improved. Therefore, the amount of displacement of the protrusion 154 can be increased efficiently.

  Here, the shape characteristic of the stator 150 will be described. FIG. 17 is a diagram showing dimensions of the stator 150, and the table of FIG. 18 is a table showing dimensions of each part of the two types of stators 150 of type A and type B having different dimensions. The materials of the two types of type A and type B are stainless steel, and the dimension in the depth direction (direction perpendicular to the moving direction of the moving element) in these drawings is 3 mm.

  The dimension G is the width of the groove 153, the dimension H1 is the height of the protrusion 154 from the base 152, H2 is the height of the lower wide portion of the protrusion 154 from the base 152, and H3 is the leg. The heights of the portions 156 and 157 from the base portion 152, W1 is the thickness (width) of the leg portions 156 and 157, and W2 is the boundary between the lower wide portion and the upper narrow portion of the protrusion 154. The height W3 from the base portion 152 is the thickness (width) of the protrusion 154.

  FIG. 19 is a perspective view showing the operation of the actuator 100. As shown in this figure, in the actuator 100, the electromechanical conversion units 160 and 162 are relatively expanded and contracted, so that the protrusions 154 are orthogonal to the expansion and contraction directions of the electromechanical conversion units 160 and 162 (hereinafter referred to as the horizontal direction). Direction). In addition, as the protrusion 154 contacts the rotor 140 and is displaced laterally (hereinafter referred to as lateral displacement), the protrusion 154 has a reaction force in the direction opposite to the displacement direction of the protrusion 154 ( Hereinafter, a lateral reaction force) acts.

  FIG. 20 is a graph showing the relationship between the lateral reaction force (N) and the lateral displacement (μm) for each of the type A stator 150 and the type B stator 150. As shown in this graph, when the lateral reaction force is 2.5 N or less, it is appropriate to use Type A, and when the lateral reaction force is 2.5 N or more, it is appropriate to use Type B. It is.

  If the material of the protrusion 154 is, for example, aluminum, the protrusion 154 is easily deformed by the force received from the electromechanical converters 160 and 162, and the amount of lateral displacement of the protrusion 154 can be increased. Further, in the type A and type B stators 150, when W3 = W2, the rigidity of the protrusion 154 with respect to the lateral reaction force can be improved. Further, by narrowing G, which is the distance between the pair of leg portions 156, 157, the lateral displacement amount can be further increased, and the distance G is equal to or less than the height H1 from the base portion 152 of the protruding portion 154. It is preferable to become.

  FIG. 21 is a side sectional view showing a schematic configuration of an imaging apparatus 700 including the motor 10. As shown in this figure, the imaging apparatus 700 includes an optical member 420, a lens barrel 430, a motor 10, an imaging unit 500, and a control unit 550. The lens barrel 430 accommodates the optical member 420.

  The motor 10 moves the optical member 420. The imaging unit 500 captures an image formed by the optical member 420. The control unit 550 controls the motor 10 and the imaging unit 500.

  The imaging apparatus 700 includes an optical member 420, a lens barrel 430, a lens unit 410 including the motor 10, and a body 460. The lens unit 410 is detachably attached to the body 460 via the mount 450.

  The optical member 420 includes a front lens 422, a compensator lens 424, a focusing lens 426, and a main lens 428, which are sequentially arranged from the incident end corresponding to the left side in the drawing. An iris unit 440 is disposed between the focusing lens 426 and the main lens 428.

  The motor 10 is disposed in the middle of the lens barrel 430 in the optical axis direction and below the focusing lens 426 having a relatively small diameter. Thereby, the motor 10 is accommodated in the lens barrel 430 without increasing the diameter of the lens barrel 430. The motor 10 advances or retracts the focusing lens 426 in the optical axis direction via, for example, a gear train.

  The body 460 accommodates optical members including the main mirror 540, the pentaprism 470, and the eyepiece system 490. The main mirror 540 is located between a standby position inclined on the optical path of incident light incident through the lens unit 410 and an imaging position (indicated by a dotted line in the figure) that rises while avoiding incident light. Moving.

  The main mirror 540 at the standby position guides most of the incident light to the pentaprism 470 disposed above. Since the pentaprism 470 emits a reflection of incident light toward the eyepiece system 490, the image on the focusing screen can be viewed as a normal image from the eyepiece system 490. The remainder of the incident light is guided to the photometric unit 480 by the pentaprism 470. The photometric unit 480 measures the intensity and distribution of incident light.

  A half mirror 492 is disposed between the pentaprism 470 and the eyepiece system 490 to superimpose the display image formed on the finder liquid crystal 494 on the image of the focusing screen. The display image is displayed so as to overlap the image projected from the pentaprism 470.

  The main mirror 540 has a sub mirror 542 on the back surface of the incident light incident surface. The sub mirror 542 guides part of the incident light transmitted through the main mirror 540 to the distance measuring unit 530 disposed below. Thereby, when the main mirror 540 is in the standby position, the distance measuring unit 530 measures the distance to the subject. When the main mirror 540 is moved to the photographing position, the sub mirror 542 is also retracted from the optical path of the incident light.

  Further, a shutter 520, an optical filter 510, and an imaging unit 500 are sequentially arranged behind the main mirror 540 with respect to incident light. When the shutter 520 is opened, the main mirror 540 moves to the photographing position immediately before the shutter 520 is opened, so that incident light travels straight and enters the imaging unit 500. Thereby, an image formed by incident light is converted into an electrical signal. Thereby, the imaging unit 500 captures an image formed by the lens unit 410.

  In the imaging device 700, the lens unit 410 and the body 460 are also electrically coupled. Therefore, for example, the autofocus mechanism can be formed by controlling the rotation of the motor 10 according to the information on the distance to the subject detected by the distance measuring unit 530 on the body 460 side. In addition, a focus aid mechanism can be formed by the distance measuring unit 530 referring to the operation amount of the motor 10. The motor 10 and the imaging unit 500 are controlled by the control unit 550 as described above.

  Here, as described above, the output torque of the motor 10 can be increased efficiently. Therefore, since the driving force of the autofocus mechanism can be increased efficiently, it is possible to save power and drive the autofocus mechanism with a high driving force.

  Although the case where the focusing lens 426 is moved by the motor 10 is illustrated, it goes without saying that the opening and closing of the iris unit 440, the movement of the variator lens of the zoom lens, and the like can be driven by the motor 10. Also in this case, by referring to information with the photometric unit 480, the finder liquid crystal 494, etc. via the electrical signal, the motor 10 contributes to automating exposure, execution of a scene mode, execution of bracket photography, and the like. In the imaging apparatus 700, the motor 20 may be used instead of the motor 10.

  As described above, the motor 10 can be suitably used for driving a focusing mechanism, a zoom mechanism, a camera shake correction mechanism, and the like in an optical system such as a photographing machine and binoculars. Furthermore, it can be used for power sources such as precision stages, more specifically electron beam lithography equipment, various stages for inspection equipment, moving mechanisms for cell injectors for biotechnology, moving beds for nuclear magnetic resonance equipment, etc. Needless to say, it is not limited to.

  FIG. 22 is a perspective view showing the inside of the lens unit 300 including the actuator 200. The lens unit 300 can be attached to the body 460. As shown in this figure, the lens unit 300 includes a focusing lens 426, a lens holding frame 302 that holds the focusing lens 426, and a pair of guide bars 304 that guide the movement of the lens holding frame 302 in the optical axis direction. 306 is arranged. A bearing portion 308 is provided on the left side of the lens holding frame 302, and a pair of front and rear bearing portions 310 and 312 are provided on the upper right portion of the lens holding frame 302. The guide bar 304 is slidably inserted into the bearing portion 308, and the guide bar 306 is slidably inserted into the bearing portions 310 and 312.

  The bearing portion 310 and the bearing portion 312 are connected by a stay 314 extending in the optical axis direction. A rectangular plate-like moving body 316 whose longitudinal direction is the optical axis direction is suspended below the stay 314 so as to be displaceable in the vertical direction. Further, a leaf spring 318 is disposed between the lower portion of the stay 314 and the moving body 316. The leaf spring 318 biases the moving body 316 downward.

  Here, the actuator 200 is disposed below the moving body 316, and the moving body 316 is pressed against the protrusion 154 of the actuator 200 by a plate spring 318. The actuator 200 is arranged such that the electromechanical conversion units 160 and 162 are arranged in the optical axis direction. Therefore, when the actuator 200 is operated by the above-described method, a thrust force in the optical axis direction is applied from the protrusion 154 to the moving body 316, and the lens holding frame 302 and the focusing lens 426 are moved in the optical axis direction. Moved. In the lens unit 300, the actuator 100 may be used instead of the actuator 200.

  As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. It will be apparent to those skilled in the art that various modifications or improvements can be added to the above-described embodiment. It is apparent from the scope of the claims that the embodiments added with such changes or improvements can be included in the technical scope of the present invention.

It is a perspective view showing motor 10 provided with actuator 100 concerning one embodiment. 1 is an exploded perspective view showing a motor 10. FIG. 1 is a side sectional view showing a motor 10. FIG. FIG. 4 is a sectional view taken along line 4-4 of FIG. 3. 2 is a perspective view showing an actuator 100. FIG. FIG. 5 is a diagram showing an outline of an operation of a stator 150. 6 is a graph showing a drive voltage waveform of the electromechanical converter 160 and a drive voltage waveform of the electromechanical converter 162. 5 is a side view showing the operation of the stator 150. FIG. It is a perspective view which shows the motor 20 provided with the actuator 200 which concerns on other embodiment. 2 is an exploded perspective view showing a motor 20. FIG. 2 is a side sectional view showing a motor 20. FIG. 2 is a perspective view showing an actuator 200. FIG. FIG. 5 is a diagram showing an outline of an operation of a stator 150. 5 is a graph showing a drive voltage waveform of electromechanical converters 160 and 162 and a drive voltage waveform of electromechanical converter 240. FIG. 5 is a diagram showing an outline of an operation of a stator 150. 5 is a graph showing a drive voltage waveform of electromechanical converters 160 and 162 and a drive voltage waveform of electromechanical converter 240. It is a top view which shows the Example which has arrange | positioned the four actuators 100 at the space | interval of (pi) / 2 in the rotation direction. FIG. 5 is a diagram showing an outline of an operation of a stator 150. 5 is a graph showing a drive voltage waveform of electromechanical converters 160 and 162 and a drive voltage waveform of electromechanical converter 240. It is a front view which shows the actuator 600 which concerns on other embodiment. It is a figure which shows the dimension of the stator 150. FIG. It is a table | surface showing the dimension of each part of two types of stator 150 of type A and type B from which a dimension differs. FIG. 6 is a perspective view showing the operation of the actuator 100. 4 is a graph showing a relationship between a lateral reaction force (N) and a lateral displacement (μm) for each of a type A stator 150 and a type B stator 150. 2 is a side sectional view showing a schematic configuration of an imaging apparatus 700 including a motor 10. FIG. It is a perspective view which shows the inside of the lens unit 300 provided with the actuator 200. FIG.

10, 20 Motor, 100 Actuator, 110 Rotating shaft, 112 Screw part, 114 Flange part, 120 Mounting plate, 122 Fastening hole, 130 Energizing member, 140 Rotor, 142 Bearing, 144 Gear part, 150 Stator, 152 Base part , 153 Groove, 154 Projection, 156, 157 Leg, 160 Electromechanical converter, 161 Gap, 162 Electromechanical converter, 170, 172 Flexible printed wiring board, 171, 173 Driver, 175 Waveform shaper, 180 Base, 190 base, 200 actuator, 210, 220 nut, 230 washer, 240 electromechanical converter, 250 flexible printed wiring board, 260 base, 300 lens unit, 302 lens holding frame, 304, 306 guide bar, 308, 10, 312 Bearing portion, 314 stay, 316 moving body, 318 leaf spring, 410 lens unit, 420 optical member, 426 focusing lens, 428 main lens, 430 lens barrel, 440 iris unit, 450 mount, 460 body, 470 penta Prism, 480 Photometric unit, 490 Eyepiece system, 492 Half mirror, 494 Finder liquid crystal, 500 Imaging unit, 510 Optical filter, 520 Shutter, 530 Distance measuring unit, 540 Main mirror, 542 Sub mirror, 550 Control unit, 600 Actuator, 602, 604, 606, 608 groove, 700 imaging device, 1521 base portion, 1522 base portion

Claims (12)

An actuator for moving the slider,
The movable element extends from the movable element in a direction perpendicular to the moving direction of the movable element toward the movable element, and is provided by a groove provided on the movable element side from an end far from the movable element. A protrusion having a pair of legs branched in the moving direction of
A first electromechanical converter that supports one of the pair of legs and is expanded and contracted in a direction intersecting a moving direction of the moving element by being supplied with electric power;
By supporting the other of the pair of leg portions and being supplied with electric power, the first electromechanical conversion unit expands and contracts in a direction intersecting the moving direction of the moving element, thereby extending the first In cooperation with an electromechanical converter, a second electromechanical converter that swings the protrusion in the moving direction of the mover while displacing the protrusion toward the mover;
An actuator comprising:   The first electromechanical conversion unit and the second electromechanical conversion unit cooperate to swing in the moving direction of the moving element while displacing the projecting part toward the moving element. The actuator according to claim 1, wherein the actuator is caused to perform a circular motion that swings in a direction opposite to a moving direction of the moving element while being displaced to the opposite side of the moving part.   It is arranged on the opposite side of the first electromechanical converter and the second electromechanical converter with respect to the protrusion, and supports the first electromechanical converter and the second electromechanical converter. The actuator according to claim 2, further comprising a third electromechanical converter that expands and contracts in a direction orthogonal to a moving direction of the moving element. The first electromechanical conversion unit and the second electromechanical conversion unit cooperate to cause the protrusion to reciprocate in a swinging direction in the moving direction of the moving element and in a direction opposite to the moving direction.
It is arranged on the opposite side of the first electromechanical converter and the second electromechanical converter with respect to the protrusion, and supports the first electromechanical converter and the second electromechanical converter. The first electromechanical conversion unit is expanded and contracted in a direction different from that of the first electromechanical conversion unit and the second electromechanical conversion unit in a direction orthogonal to the moving direction of the moving element. In cooperation with the projection, the protrusion is swung in the moving direction of the moving element while being displaced toward the moving element, and the moving direction of the moving element is reversed while being displaced to the opposite side of the moving element. The actuator according to claim 1, further comprising a third electromechanical converter that performs a circular motion that swings toward the bottom.   One of the pair of legs is supported by a downstream end of the moving direction of the mover in the first electromechanical converter, and the other of the pair of legs is the second electromechanical converter in the second electromechanical converter. The actuator according to any one of claims 1 to 4, wherein the actuator is supported at an upstream end portion in a moving direction of the moving element. One is joined to the first electromechanical converter, the other is joined to the second electromechanical converter, the one is joined to one of the pair of legs, and the other is joined to the other of the pair of legs. It has a pair of base parts,
The actuator according to claim 5, wherein a thin portion thinner than the leg portion is formed at a joint portion between the leg portion and the base portion. The actuator according to any one of claims 1 to 6, and
A rotor as the mover that is rotated by the actuator;
A drive device comprising: A plurality of the actuators are arranged side by side in the moving direction of the mover,
The drive device according to claim 7, wherein at least one of the protrusions is circularly moved with a phase different from that of the other protrusions. The four actuators are arranged at equal intervals in the rotation direction of the rotor,
9. The protrusions adjacent to each other in the rotation direction of the rotor are circularly moved in different phases, and a pair of protrusions arranged symmetrically with respect to the rotation center of the rotor are synchronously moved circularly. The drive device described in 1. The actuator according to any one of claims 1 to 6, and
A slider as a mover that is linearly moved by the actuator;
A drive device comprising: The drive device according to any one of claims 7 to 10, and
An optical member that is moved in the optical axis direction by the driving device;
A lens unit comprising: The drive device according to any one of claims 7 to 10, and
An optical member that is moved in the optical axis direction by the driving device;
An imaging unit that captures an image formed by the optical member;
An imaging apparatus comprising:

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