JP2008005568A - Linear vibration actuator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a linear vibration actuator for moving an external drive object relatively by utilizing ultrasonic vibration. <P>SOLUTION: When a high frequency voltage is applied from a drive control section 10 to an interdigital electrode 6 at one end of a lower stator 2 and to an interdigital electrode 8 at one end of an upper stator 3, and matching is made by using the interdigital electrodes 7 and 9 at the other ends as wave receiving electrodes, a surface elastic wave traveling in the +X direction is generated on the upper surface of the lower stator 2 and the lower surface of the upper stator 3 formed of a piezoelectric substrate. A slider 4 brought into pressure contact with the surface of the lower stator 2 and the upper stator 3 with a predetermined pressing force of a leaf spring 5 is moved in the -X direction by the surface elastic wave and a drive object 12 on the outside of a casing 1 moves relatively through a wire 11. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a linear vibration actuator, and more particularly to an actuator that relatively moves a drive object using ultrasonic vibration.

An apparatus that conveys an object using an ultrasonic motor is known. For example, the conveying device disclosed in Patent Document 1 presses and holds a magnetic card, which is an object to be conveyed, between a pair of rod-shaped elastic bodies, and applies high-frequency power to piezoelectric ceramics bonded to both elastic bodies. The magnetic card is conveyed by generating ultrasonic traveling waves in these elastic bodies. By using ultrasonic vibration, it is possible to obtain a transfer device having a large thrust while being thin.
By mounting the transport device of Patent Document 1 on a magnetic card reader / writer or the like, the magnetic card is transported at high speed, and during the transport, data is read from the magnetic card and written to the magnetic card by the magnetic head. It can be carried out.

JP-A-5-266260

However, for example, in a robot hand or the like, when a transport device such as Patent Document 1 is used to move a hand or a finger, the hand or finger that is the object to be driven is pressed and clamped by a pair of rod-like or plate-like elastic bodies. In this state, a traveling wave of ultrasonic waves must be generated in both elastic bodies. For this reason, as the robot hand, the elastic bodies arranged on both sides of the hand and fingers are obstructive, and the moving direction of the hands and fingers is also limited to the direction along the traveling direction of the traveling wave in the elastic bodies. As a result, it becomes extremely inconvenient. This is due to the fact that the driven object is located inside the transport device. In particular, when driving a plurality of objects, the size of the actuator is large, so downsizing has been a problem.
Accordingly, the present invention has been made to solve such problems, and an object thereof is to provide a linear vibration actuator capable of relatively moving an external driving object using ultrasonic vibration. And

A linear type vibration actuator according to the present invention includes a slide mechanism portion in which a slider is movably disposed in a predetermined direction along the surface of a plate-like or rod-like stator, and the slider is an object to be driven outside the slide mechanism portion. A connecting member that is connected to the surface of the stator, a preload unit that pressurizes the slider against the surface of the stator, and a traveling wave along the predetermined direction is generated on one of the opposing surfaces of the stator and the slider. A traveling wave generating means, and a traveling wave is generated by the traveling wave generating means to move the slider in the slide mechanism section along the surface of the stator, thereby moving the driven object relative to each other via the connecting member. It is.
Note that “relatively moving the driving object” includes the following three modes.
(1) The driven object moves relative to the stator whose position is fixed.
(2) The stator moves relative to the driving object whose position is fixed.
(3) The relative position of the stator and the driving object changes while the stator and the driving object move together.

The slide mechanism unit can be configured to include a pair of stators arranged in parallel to each other and a slider arranged between the pair of stators.
Preferably, the slide mechanism part has a linear guide for guiding the movement of the slider along the surface of the stator.

In addition, a plurality of slide mechanism portions are stacked on each other, and the plurality of slide mechanism portions stacked on each other with a common preloading means are pressed to bring the slider into pressure contact with the surface of the stator in each slide mechanism portion. The sliders of the slide mechanism unit may be coupled to a plurality of driving objects through a plurality of coupling members, respectively, and the sliders of the plurality of slide mechanism units may be moved by a plurality of traveling wave generating units, respectively.
In this case, the plurality of slide mechanism portions each include an upper stator and a lower stator arranged in parallel with each other and a slider arranged between the upper stator and the lower stator, and the lower stator of the upper slide mechanism portion is the lower stage. It can also comprise so that it may serve as the upper stator of this slide mechanism part.
Further, each of the plurality of slide mechanism units includes a plurality of linear guides for guiding the movement of the slider along the surface of the stator, and the preload means pressurizes the plurality of slide mechanism units via the plurality of linear guides. It may be.

The traveling wave generating means can generate a surface acoustic wave as the traveling wave.
In this case, the stator is formed from a piezoelectric substrate, and as the traveling wave generating means, an interdigital electrode formed on the surface of the stator and a drive control unit that applies a high-frequency voltage to the interdigital electrode may be used. Alternatively, the slider may be formed from a piezoelectric substrate, and as the traveling wave generating means, an interdigital electrode formed on the surface of the slider and a drive control unit that applies a high-frequency voltage to the interdigital electrode may be used.

The traveling wave generating means can also generate a bending traveling wave as a traveling wave.
In this case, the stator may be formed of an elastic body, and a piezoelectric element disposed on the surface of the stator and a drive control unit that applies a high-frequency voltage to the piezoelectric element may be used as traveling wave generating means. Alternatively, the slider may be formed of an elastic body, and a piezoelectric element disposed on the surface of the slider and a drive control unit that applies a high frequency voltage to the piezoelectric element may be used as traveling wave generating means.

  According to the present invention, it is possible to relatively move an external driving object using ultrasonic vibration.

Embodiments of the present invention will be described below with reference to the accompanying drawings.
Embodiment 1
FIG. 1 shows the configuration of the linear vibration actuator according to the first embodiment. A pair of flat plate-like lower stator 2 and upper stator 3 each formed from a piezoelectric substrate are disposed in parallel in each other in casing 1 with one end opened, and formed between these stators 2 and 3 from metal or the like. A slider 4 is arranged. The lower stator 2 is fixed to the bottom of the casing 1, and the upper stator 3 is disposed so as to sandwich the slider 4 between the lower stator 2, and the slide mechanism portion is formed by the lower stator 2, the upper stator 3, and the slider 4. S is formed. Further, a plate spring 5 is inserted as a preload means between the upper surface of the upper stator 3 and the ceiling surface of the casing 1, and the upper stator 3 is pressed toward the lower stator 2 by the urging force of the plate spring 5, The slider 4 is pressed against the surfaces of the lower stator 2 and the upper stator 3 with a predetermined pressure.

Interdigital electrodes 6 and 7 are formed in the vicinity of both ends of the upper surface of the lower stator 2 facing the slider 4. Similarly, the interdigital electrodes 8 and 7 are formed in the vicinity of both ends of the lower surface of the upper stator 3 facing the slider 4. 9 is formed. And the drive control part 10 which has a high frequency power supply is electrically connected to these interdigital electrodes 6-9. The interdigital electrodes 6 to 9 and the drive control unit 10 form traveling wave generating means.
Here, the direction from the interdigital electrodes 6 and 8 at one end of the lower stator 2 and the upper stator 3 to the interdigital electrodes 7 and 9 at the other end is the + X direction, and the interdigital shape at one end from the interdigital electrodes 7 and 9 at the other end. The direction toward the electrodes 6 and 8 is defined as a −X direction.

  Further, one end of a wire 11 as a connecting member is connected to the slider 4, and the other end of the wire 11 extends to the outside of the casing 1 through the open end of the casing 1 and is connected to the driving object 12. . It is assumed that the driven object 12 is arranged so as to be movable in the + X direction and the −X direction and is urged in a direction away from the casing 1, that is, in the + X direction by an urging means such as a spring (not shown).

  Next, the operation of the first embodiment will be described. As shown in FIG. 2, when a high frequency voltage is applied to the interdigital electrode 6 at one end of the lower stator 2 from the high frequency power supply 13 in the drive control unit 10, surface elasticity is applied to the upper surface of the lower stator 2 formed from the piezoelectric substrate. A wave is excited and propagates toward the interdigital electrode 7 at the other end. At this time, a matching circuit 14 in the drive control unit 10 is connected to the interdigital electrode 7 at the other end, and matching is performed using the interdigital electrode 7 as a receiving electrode. The surface acoustic wave becomes a traveling wave in the + X direction from the interdigital electrode 6 at one end toward the interdigital electrode 7 at the other end.

The energy of the surface acoustic wave absorbed by the interdigital electrode 7 can be consumed by a resistance for energy consumption or the like, but this energy is returned to the interdigital electrode 6 at one end to excite the traveling wave. By using it, energy efficiency can be greatly improved.
Similarly, a high-frequency voltage is applied from the drive control unit 10 to the interdigital electrode 8 at one end of the upper stator 3 and matching is performed with the interdigital electrode 9 at the other end as a receiving electrode. A surface acoustic wave traveling in the + X direction from the interdigital electrode 8 toward the interdigital electrode 9 at the other end is generated.

  Due to the traveling waves in the + X direction generated on the upper surface of the lower stator 2 and the lower surface of the upper stator 3, the slider 4 that is in pressure contact with the surfaces of the lower stator 2 and the upper stator 3 with a predetermined pressure is applied to the lower stator 2. It moves in the opposite direction to the traveling wave along the surfaces of the stator 2 and the upper stator 3, that is, in the −X direction from the interdigital electrodes 7 and 9 at the other end toward the interdigital electrodes 6 and 8 at one end. As the slider 4 moves, the driven object 12 outside the casing 1 moves relative to the −X direction through a wire 11 against an urging force such as a spring (not shown).

  Conversely, by applying a high frequency voltage to the interdigital electrodes 7 and 9 at the other ends of the lower stator 2 and the upper stator 3 and using the interdigital electrodes 6 and 8 as the receiving electrodes, respectively, Surface acoustic waves traveling in the -X direction from the interdigital electrodes 7 and 9 at the other end toward the interdigital electrodes 6 and 8 at the other end are generated on the upper surface and the lower surface of the upper stator 3, respectively, and the slider 4 moves in the + X direction. Can be made. As a result, the tension of the wire 11 connecting the slider 4 and the driving object 12 is lowered, and the driving object 12 receives a biasing force such as a spring (not shown) and relatively moves in the + X direction.

  As shown in FIG. 3, if the linear guide 15 extending in parallel with the lower stator 2 and the upper stator 3 is installed in the casing 1 and the movement of the slider 4 is guided by the linear guide 15, The slider 4 can be smoothly moved along the surface of the upper stator 3.

Embodiment 2
FIG. 4 shows the configuration of the linear vibration actuator according to the second embodiment. In the second embodiment, four slide mechanism portions S used in the first embodiment are stacked on each other and housed in a casing 21 to constitute a stacked actuator. Four slide mechanism portions S are stacked on each other in a casing 21 whose one end is open, and the lower stator 2 of the upper slide mechanism portion S is positioned on the upper surface of the upper stator 3 of the lower slide mechanism portion S. Further, a leaf spring 5 is inserted between the upper surface of the uppermost slide mechanism portion S and the ceiling surface of the casing 21. The leaf spring 5 acts as a preload means in common to the four slide mechanism portions S, and applies the slider 4 of each slide mechanism portion S to the surfaces of the lower stator 2 and the upper stator 3 with a predetermined pressure. Press contact.
The sliders 4 of the four slide mechanism portions S are connected to different driving objects 12 through corresponding wires 11 respectively. Furthermore, the drive control parts 10 corresponding to the interdigital electrodes 6 to 9 of the four slide mechanism parts S are electrically connected.

With such a configuration, the sliders 4 of the four slide mechanism sections S can be independently moved by the corresponding drive control sections 10, and the four drive objects 12 can be driven with multiple degrees of freedom. It becomes.
Since the four slide mechanism portions S are stacked and the four leaf mechanism portions S are preloaded by the common leaf spring 5, a thin multi-degree-of-freedom linear vibration actuator with a small number of parts is realized.
Further, by using the common leaf spring 5, the preload applied to the four slide mechanism portions S can be made uniform, and the movement characteristics of the slider 4 in the four slide mechanism portions S can be made uniform. An actuator is configured.
Furthermore, since surface acoustic waves are used as traveling waves, the surfaces of the stators 2 and 3 opposite to the slider 4 do not vibrate, and therefore any part of these surfaces of the stators 2 and 3 does not vibrate. Preload can be applied, and the configuration of the preload means can be simplified.

Embodiment 3
5 and 6 show the configuration of the linear vibration actuator according to the third embodiment. In the third embodiment, the lower stator 2 of the upper slide mechanism portion S also serves as the upper stator of the lower slide mechanism portion S in the actuator of the second embodiment shown in FIG.
Since surface acoustic waves are used as traveling waves, different surface acoustic waves can be generated on both surfaces of a single stator. Therefore, in the third embodiment, interdigital electrodes 6 and 7 are formed in the vicinity of both ends of the upper surface of the lower stator 2 of the upper slide mechanism section S, and the interdigital electrodes 6 and 7 are connected to the upper slide mechanism section. In addition to being used as a lower electrode of S, interdigital electrodes 8 and 9 are formed in the vicinity of both ends of the lower surface of the lower stator 2, and the interdigital electrodes 8 and 9 are used as upper electrodes of the lower slide mechanism S. It is used as.

  By adopting such a configuration, the stator positioned between the upper slide mechanism portion S and the lower slide mechanism portion S stacked on each other can be made into one sheet, and is thin and simple in structure. A linear vibration actuator is realized.

Embodiment 4
FIG. 7 shows the configuration of the linear vibration actuator according to the fourth embodiment. The fourth embodiment is the same as the first embodiment except that the lower stator 2 formed from a piezoelectric substrate and the lower stator 2 formed from metal or the like instead of sandwiching the slider 4 formed from metal or the like between the upper stator 3 and the lower stator 2 are formed. A slider 24 formed of a piezoelectric substrate is sandwiched between the upper stator 23 and the upper stator 23, and the interdigital electrodes 6 and 7 are formed near both ends of the lower surface of the slider 24, and the interdigital is formed near both ends of the upper surface of the slider 24. Electrodes 8 and 9 are formed. A slide mechanism S is formed by the lower stator 22, the upper stator 23 and the slider 24. Moreover, the drive control part 10 is electrically connected to the interdigital electrodes 6-9.
The slider 24 is pressed against the surfaces of the lower stator 22 and the upper stator 23 with a predetermined pressure by the urging force of the leaf spring 5. Further, the driven object 12 outside the casing 1 is connected to the slider 24 via the wire 11.

By applying a high frequency voltage from the drive control unit 10 to the interdigital electrodes 6 and 8 at one end of the slider 24 and using the interdigital electrodes 7 and 9 at the other end as receiving electrodes, matching is performed on both sides of the slider 24. A surface acoustic wave traveling in the + X direction is generated from the electrodes 6 and 8 toward the interdigital electrodes 7 and 9, and the slider 24 moves in the + X direction. On the other hand, by applying a high frequency voltage from the drive control unit 10 to the interdigital electrodes 7 and 9 at the other end of the slider 24 and using the interdigital electrodes 6 and 8 at one end as receiving electrodes, matching is performed on both surfaces of the slider 24. Surface acoustic waves traveling in the −X direction from the interdigital electrodes 7 and 9 toward the interdigital electrodes 6 and 8 are generated, and the slider 24 moves in the −X direction.
Therefore, similarly to the first embodiment, the driven object 12 outside the casing 1 can be moved via the wire 11.

Embodiment 5
FIG. 8 shows the configuration of a linear vibration actuator according to the fifth embodiment. In the fifth embodiment, four slide mechanism portions S used in the fourth embodiment are stacked on top of each other and housed in a casing 21 to form a stacked actuator and at the bottom of the upper slide mechanism portion S. The stator 22 also serves as the upper stator of the lower slide mechanism portion S. Four slide mechanism portions S are stacked on each other in the casing 21 with one end opened, and only the lower stator 22 of the upper slide mechanism portion S is located between the slide mechanism portions S that overlap each other. The lower stator 22 of the mechanism portion S also serves as the upper stator of the lower slide mechanism portion S. A leaf spring 5 is inserted between the upper surface of the uppermost slide mechanism portion S and the ceiling surface of the casing 21, and the sliders 24 of the four slide mechanism portions S are respectively connected to the lower stator 22 and the upper stator 23 by this leaf spring 5. The surface is pressed against the surface with a predetermined pressure.

  Although not shown in the drawings, the sliders 24 of the four slide mechanism portions S are connected to different driving objects via the corresponding wires 11. Further, drive control units respectively corresponding to the interdigital electrodes 6 to 9 formed on both surfaces of the slider 24 of the four slide mechanism units S are electrically connected.

With such a configuration, the sliders 24 of the four slide mechanism sections S can be independently moved by the corresponding drive control sections, similarly to the second and third embodiments described above, and the four drive objects Can be driven with multiple degrees of freedom.
Since the four slide mechanism portions S are stacked and the four leaf mechanism portions S are preloaded by the common leaf spring 5, a thin multi-degree-of-freedom linear vibration actuator with a small number of parts is realized.
Further, by using the common leaf spring 5, the preload applied to the four slide mechanism portions S can be made uniform, and the movement characteristics of the sliders 24 in the four slide mechanism portions S can be made uniform, so that a high quality multi-degree of freedom can be obtained. An actuator is configured.

Embodiment 6
FIG. 9 shows the configuration of a linear vibration actuator according to the sixth embodiment. In the sixth embodiment, the lower stator 32 and the upper stator 33 made of an elastic body are used instead of the lower stator 2 and the upper stator 3 in the first embodiment, and the lower stator 32 is replaced with the interdigital electrodes 6 and 7. Piezoelectric elements 36 and 37 are affixed in the vicinity of both ends of the upper surface, and piezoelectric elements 38 and 39 are affixed in the vicinity of both ends of the lower surface of the upper stator 33 instead of the interdigital electrodes 8 and 9, respectively. A slide mechanism S is formed by the lower stator 32, the upper stator 33 and the slider 4. In addition, the drive control unit 10 is electrically connected to the piezoelectric elements 36 to 39.
The slider 4 is pressed against the surfaces of the lower stator 32 and the upper stator 33 with a predetermined pressure by the urging force of the leaf spring 5. In addition, a driving object 12 outside the casing 1 is connected to the slider 4 via a wire 11.

  As shown in FIG. 10, when a high frequency voltage is applied to the piezoelectric element 36 at one end of the lower stator 2 from the high frequency power supply 13 in the drive control unit 10, a flexural vibration is generated in the lower stator 32 made of an elastic body, and the other end It propagates toward the piezoelectric element 37. At this time, by connecting the matching circuit 14 in the drive control unit 10 to the piezoelectric element 37 at the other end and performing matching using the piezoelectric element 37 as a vibration absorption side element, the flexural vibration is absorbed by the piezoelectric element 37. The generation of the reflected wave is suppressed, and a bending traveling wave in the + X direction from the piezoelectric element 36 at one end toward the piezoelectric element 37 at the other end is generated.

The energy efficiency can be greatly improved by using the energy of the flexural vibration absorbed by the piezoelectric element 37 at the other end to return to the side of the piezoelectric element 36 and utilizing it for the excitation of the flexural vibration.
Similarly, a high-frequency voltage is applied from the drive control unit 10 to the piezoelectric element 38 at one end of the upper stator 33 and the piezoelectric element 39 at the other end is matched as a vibration-absorbing side element, whereby a piezoelectric element at one end is formed on the lower surface of the upper stator 33. A bending traveling wave is generated that travels in the + X direction from the element 38 toward the piezoelectric element 39 at the other end.

  Due to the traveling waves in the + X direction generated on the upper surface of the lower stator 32 and the lower surface of the upper stator 33, the slider 4 that is in pressure contact with the surfaces of the lower stator 32 and the upper stator 33 with a predetermined pressure is applied to the lower stator 32. The traveling wave moves in the opposite direction along the surfaces of the stator 32 and the upper stator 33, that is, in the −X direction. Along with the movement of the slider 4, the driven object 12 outside the casing 1 moves in the −X direction against a biasing force such as a spring (not shown) via the wire 11.

  Conversely, by applying a high frequency voltage to the piezoelectric elements 37 and 39 at the other ends of the lower stator 32 and the upper stator 33 and using the piezoelectric elements 36 and 38 at one end as the vibration-absorbing side elements, respectively, Deflection traveling waves traveling in the −X direction are generated on the lower surface of the upper stator 33 from the piezoelectric elements 37 and 39 on the other end toward the piezoelectric elements 36 and 38 on the other end, respectively, and the slider 4 can be moved in the + X direction. . As a result, the tension of the wire 11 connecting the slider 4 and the driving object 12 is lowered, and the driving object 12 is moved in the + X direction by receiving an urging force such as a spring (not shown).

Embodiment 7
11 and 12 show the configuration of the linear vibration actuator according to the seventh embodiment. In the seventh embodiment, four slide mechanism portions S using a bending traveling wave are stacked on top of each other and housed in a casing 21 to constitute a stacked actuator. Each slide mechanism S is formed of an upper stator 33 made of an elastic body, a linear guide 40 extending in parallel with the upper stator 33, and a slider 4 held movably by the linear guide 40. The lower surface of the upper stator 33 is in contact with the upper surface of the slider 4, and the leg portion 41 of the linear guide 40 is positioned below the lower surface of the slider 4.

  Four slide mechanism portions S are stacked on each other in the casing 21 whose one end is open, and the leg portion 41 of the linear guide 40 of the upper slide mechanism portion S is placed on the upper surface of the upper stator 33 of the lower slide mechanism portion S. ing. A leaf spring 5 is inserted between the upper surface of the uppermost slide mechanism portion S and the ceiling surface of the casing 21. The upper stator 33 of the uppermost slide mechanism section S is pressed against the slider 4 by the urging force of the plate spring 5, and further, the plate spring 5 is applied to the upper stator 33 of the lower slide mechanism section S via the linear guide 40. The urging force of acts. In this way, the leaf spring 5 acts as a preload means in common with the four slide mechanism portions S, and applies the slider 4 of each slide mechanism portion S to the lower surface of the upper stator 33 with a predetermined pressure. Press contact.

  Piezoelectric elements 38 and 39 are affixed in the vicinity of both ends of the lower surface of the upper stator 33 of each slide mechanism S. Although not shown, drive control units corresponding to the piezoelectric elements 38 and 39 of the upper stator 33 of the four slide mechanism units S are electrically connected. In addition, the sliders 4 of the four slide mechanism portions S are connected to different driving objects through corresponding wires 11.

With such a configuration, the sliders 4 of the four slide mechanism portions S can be independently moved by the corresponding drive control units as in the second, third, and fifth embodiments described above. It becomes possible to drive the object with multiple degrees of freedom.
Since the four slide mechanism portions S are stacked and the four leaf mechanism portions S are preloaded by the common leaf spring 5, a thin multi-degree-of-freedom linear vibration actuator with a small number of parts is realized.
Further, by using the common leaf spring 5, the preload applied to the four slide mechanism portions S can be made uniform, and the movement characteristics of the slider 4 in the four slide mechanism portions S can be made uniform. An actuator is configured.

Embodiment 8
FIG. 13 shows the configuration of a linear vibration actuator according to the eighth embodiment. In the eighth embodiment, both end portions of the upper surface of the slider 44 formed of an elastic body instead of attaching the piezoelectric elements 36 to 39 to the surfaces of the lower stator 32 and the upper stator 33 made of an elastic body in the sixth embodiment. Piezoelectric elements 36 and 37 are attached in the vicinity, and the slider 44 is sandwiched between a lower stator 22 and an upper stator 23 formed of metal or the like. A slide mechanism S is formed by the lower stator 22, the upper stator 23 and the slider 44. The drive control unit 10 is electrically connected to the piezoelectric elements 36 and 37 of the slider 44.
Note that the slider 44 is pressed against the surfaces of the lower stator 22 and the upper stator 23 with a predetermined pressing force by the urging force of the leaf spring 5. Further, the driven object 12 outside the casing 1 is connected to the slider 44 via the wire 11.

A high frequency voltage is applied from the drive control unit 10 to the piezoelectric element 36 at one end of the slider 44 and matching is performed with the piezoelectric element 37 at the other end as a vibration-absorbing side element. A deflection traveling wave in the + X direction toward the piezoelectric element 37 at the other end is generated, and the slider 44 moves in the + X direction. On the other hand, a high-frequency voltage is applied from the drive control unit 10 to the piezoelectric element 37 at the other end of the slider 44, and the piezoelectric element 36 at one end is matched as a vibration-absorbing side element, so A bending traveling wave in the −X direction from the element 37 toward the piezoelectric element 36 at one end is generated, and the slider 44 moves in the −X direction.
Therefore, similarly to the sixth embodiment, the driven object 12 outside the casing 1 can be moved via the wire 11.
Instead of pasting the piezoelectric elements 36 and 37 on the upper surface of the slider 44, the piezoelectric elements 36 and 37 may be pasted near both ends of the lower surface of the slider 44, respectively.

Embodiment 9
FIG. 14 shows the configuration of a linear vibration actuator according to the ninth embodiment. In the ninth embodiment, four slide mechanism portions S used in the eighth embodiment are stacked on top of each other and housed in the casing 21 to constitute a stacked actuator and at the bottom of the upper slide mechanism portion S. The stator 22 also serves as the upper stator of the lower slide mechanism portion S. Four slide mechanism portions S are stacked on each other in the casing 21 with one end opened, and only the lower stator 22 of the upper slide mechanism portion S is located between the slide mechanism portions S that overlap each other. The lower stator 22 of the mechanism portion S also serves as the upper stator of the lower slide mechanism portion S. A leaf spring 5 is inserted between the upper surface of the uppermost slide mechanism portion S and the ceiling surface of the casing 21, and the sliders 44 of the four slide mechanism portions S are respectively connected to the lower stator 22 and the upper stator 23 by the leaf spring 5. The surface is pressed against the surface with a predetermined pressure.

  Although not shown, the sliders 44 of the four slide mechanism portions S are connected to different driving objects via the corresponding wires 11. Furthermore, drive control units respectively corresponding to the piezoelectric elements 36 and 37 formed on the upper surfaces of the sliders 44 of the four slide mechanism units S are electrically connected.

With such a configuration, the sliders 44 of the four slide mechanism portions S can be independently moved by the corresponding drive control portions as in the second, third, fifth, and seventh embodiments described above. It becomes possible to drive one drive object with multiple degrees of freedom.
Since the four slide mechanism portions S are stacked and the four leaf mechanism portions S are preloaded by the common leaf spring 5, a thin multi-degree-of-freedom linear vibration actuator with a small number of parts is realized.
Further, by using the common leaf spring 5, the preload applied to the four slide mechanism portions S can be made uniform, and the movement characteristics of the slider 44 in the four slide mechanism portions S can be made uniform. An actuator is configured.

In the first to ninth embodiments, the wire 11 is used as a connecting member for connecting the external drive object 12 to the sliders 4, 24 and 44. However, the present invention is not limited to this, and a rigid rod or plate shape is used. These members can also be used.
In the first to ninth embodiments, the flat lower stators 2, 22, and 32 and the upper stators 3, 23, and 33 are used. However, rod-shaped stators may be used. Furthermore, if the slider can be moved, a curved stator can be used.
Although the plate spring 5 is used as the preloading means, various urging means such as a disc spring and a coil spring can be used.
In the second to sixth, eighth, ninth, and ninth embodiments, it is preferable to guide the movement of the sliders 4, 24, and 44 by the linear guide 15 as shown in FIG.

  In Embodiments 2, 3, 5, 7 and 9 described above, the sliders 4, 24 and 44 of the four slide mechanism portions S are connected to different driving objects 12 and independently driven. It is also possible to connect the sliders 4, 24 and 44 of the slide mechanism S to the common drive object 12. In this way, it is possible to obtain a thrust four times that in the case where the driving object 12 is moved by the single slide mechanism S. In this case, the common drive control unit 10 is electrically connected to the interdigital electrodes 6 to 9 or the piezoelectric elements 36 to 39 of the four slide mechanism units S, and the sliders 4 and 24 of the four slide mechanism units S and 44 may be moved in synchronization.

  In the second, third, fifth, seventh, and ninth embodiments, the four slide mechanism portions S are stacked on each other. However, the number of stacked slide mechanism portions S is not limited to four. Three, or five or more slide mechanism portions S can be stacked.

  In each of the above-described embodiments, the driven object 12 is disposed so as to be movable in the + X direction and the −X direction, and the sliders 4, 24, 44 move with respect to the lower stators 2, 22, 32 and the upper stators 3, 23, 33. The drive object 12 is moved with respect to the casing 1 by the above, but conversely, the casing 1 is movably disposed in the + X direction and the −X direction, and a fixed object is employed as the drive object 12. The casing 1 can also be configured to move with respect to the object 12.

  For example, in the first embodiment shown in FIG. 1, a high-frequency voltage is applied from the drive control unit 10 to the interdigital electrodes 6 and 8 at one end of the lower stator 2 and the upper stator 3, and the interdigital electrodes 7 and 9 at the other end are applied. By matching the receiving electrodes, surface acoustic waves traveling in the + X direction are generated on the upper surface of the lower stator 2 and the lower surface of the upper stator 3, and the slider 4 is relative to the lower stator 2 and the upper stator 3. Move in the -X direction. At this time, since the slider 4 is connected to the driven object 12 that is a fixed object via the wire 11, the slider 4 cannot actually move in the −X direction due to the tension of the wire 11. The stator 3 moves relative to the slider 4 in the + X direction. In this way, the casing 1 can be moved in the + X direction.

When the casing 1 is moved in the −X direction, the slider 4 must be moved in the + X direction relative to the lower stator 2 and the upper stator 3, so that a rigid rod is used instead of the wire 11. It is preferable to connect the slider 4 and the driven object 12 using a plate-like connecting member.
Similarly, in the second to ninth embodiments, the casings 1 and 21 are movably disposed in the + X direction and the −X direction, and a fixed object is used as the driving object 12, thereby allowing the driving object 12 to be moved. Thus, the casings 1 and 21 can be moved.

  When a plurality of slide mechanism portions S are stacked and used as in the second, third, fifth, seventh, and ninth embodiments, the drive target 12 connected to the sliders 4, 24, and 44 of each slide mechanism portion S is used. Are fixed objects, the sliders 4, 24 and 44 of the plurality of slide mechanism portions S may be moved in synchronization. Further, a driving object 12 as a fixed object is connected to a slider of at least one slide mechanism section S among the plurality of slide mechanism sections S, and the casing 21 is moved by the slide mechanism section S, and another slide mechanism section S is connected. It is also possible to connect the movable drive object 12 to the slider and move the movable drive object 12 by the slide mechanism S.

By using the stacked actuators according to the second, third, fifth, seventh, and ninth embodiments described above, for example, a robot hand as shown in FIG. 15 can be configured. In this robot hand, five pieces of multi-joint fingers F such as a first finger, a second finger and a third finger connected to a plurality of wires 11 of a stacked actuator A are arranged side by side. . By using the stacked actuator A, a small robot hand is realized.
When only one part of the finger F is driven, the finger F is used by using a vibration actuator having a single slider 4, 24, 44 as shown in the first, fourth, sixth, and eighth embodiments. Can also be driven.
Furthermore, the entire robot hand can be moved by attaching the robot hand to the tip of an arm (not shown) and moving the arm. In this case, the relative positions of the casings 1, 21 and the driving object 12 change while the casings 1, 21 of the vibration actuator and the finger F as the driving object 12 both move due to the movement of the arm.

FIG. 3 is a side cross-sectional view showing the configuration of the linear vibration actuator according to the first embodiment. 2 is a perspective view showing a stator used in Embodiment 1. FIG. FIG. 6 is a side cross-sectional view illustrating a configuration of a linear vibration actuator according to a modification of the first embodiment. FIG. 5 is a side cross-sectional view showing a configuration of a linear vibration actuator according to a second embodiment. FIG. 6 is a side cross-sectional view illustrating a configuration of a linear vibration actuator according to a third embodiment. FIG. 10 is a perspective view illustrating a configuration of a linear vibration actuator according to a third embodiment. FIG. 6 is a side cross-sectional view illustrating a configuration of a linear vibration actuator according to a fourth embodiment. FIG. 10 is a side cross-sectional view showing a configuration of a linear vibration actuator according to a fifth embodiment. FIG. 10 is a side cross-sectional view showing a configuration of a linear vibration actuator according to a sixth embodiment. FIG. 10 is a perspective view showing a stator used in Embodiment 6. FIG. 10 is a side sectional view showing a configuration of a linear vibration actuator according to a seventh embodiment. FIG. 10 is a front sectional view showing a configuration of a linear vibration actuator according to a seventh embodiment. FIG. 10 is a side cross-sectional view showing a configuration of a linear vibration actuator according to an eighth embodiment. FIG. 10 is a side cross-sectional view illustrating a configuration of a linear vibration actuator according to a ninth embodiment. It is a schematic front view which shows the robot hand to which this invention is applied.

Explanation of symbols

  1,21 Casing, 2,22,32 Lower stator, 3,23,33 Upper stator, 4,24,44 Slider, 5 Leaf spring, 6-9 Interdigital electrode, 10 Drive controller, 11 Wire, 12 Drive target Object, 13 high frequency power supply, 14 matching circuit, 15 and 40 linear guide, 36 to 39 piezoelectric element, 41 leg, S slide mechanism, A stacked actuator, F finger.

Claims (12)

A slide mechanism portion in which a slider is arranged so as to be movable in a predetermined direction along the surface of a plate-shaped or rod-shaped stator;
A connecting member for connecting the slider to a driving object outside the slide mechanism section;
Preloading means for pressingly contacting the slider against the surface of the stator;
Traveling wave generating means for generating a traveling wave along the predetermined direction on one of the opposing surfaces of the stator and the slider, and the traveling wave generating means generates a traveling wave to cause the slider to move to the stator. A linear vibration actuator, wherein the driven object is relatively moved through the connecting member by being moved along the surface of the linear vibration actuator.   2. The linear vibration actuator according to claim 1, wherein the slide mechanism includes a pair of stators arranged in parallel to each other and the slider arranged between the pair of stators.   The linear vibration actuator according to claim 1, wherein the slide mechanism section includes a linear guide that guides the movement of the slider along the surface of the stator. A plurality of the slide mechanism portions stacked on each other;
A common preloading unit that pressurizes and contacts the surface of the stator in each slide mechanism unit by pressurizing the plurality of slide mechanism units in a stacked state;
A plurality of connecting members that respectively connect the sliders of the plurality of slide mechanism portions to the plurality of driving objects;
The linear vibration actuator according to claim 1, further comprising: a plurality of traveling wave generating units that respectively move the sliders of the plurality of slide mechanism portions.   The plurality of slide mechanism portions include an upper stator and a lower stator arranged in parallel with each other and the slider arranged between the upper stator and the lower stator, and the lower stator of the upper slide mechanism portion is a lower stage. The linear vibration actuator according to claim 4, which also serves as an upper stator of the slide mechanism portion. The plurality of slide mechanism portions each have a plurality of linear guides for guiding the movement of the slider along the surface of the stator,
6. The linear vibration actuator according to claim 4, wherein the preload means pressurizes the plurality of slide mechanism portions via the plurality of linear guides.   The linear vibration actuator according to claim 1, wherein the traveling wave generating unit generates a surface acoustic wave as a traveling wave. The stator is formed of a piezoelectric substrate;
The linear type vibration actuator according to claim 7, wherein the traveling wave generating means includes an interdigital electrode formed on a surface of the stator and a drive control unit that applies a high frequency voltage to the interdigital electrode. The slider is formed from a piezoelectric substrate,
The linear type vibration actuator according to claim 7, wherein the traveling wave generating means includes an interdigital electrode formed on a surface of the slider and a drive control unit that applies a high frequency voltage to the interdigital electrode.   The linear vibration actuator according to any one of claims 1 to 6, wherein the traveling wave generating means generates a bending traveling wave as a traveling wave. The stator is formed of an elastic body,
The linear vibration actuator according to claim 10, wherein the traveling wave generating unit includes a piezoelectric element disposed on a surface of the stator and a drive control unit that applies a high-frequency voltage to the piezoelectric element. The slider is formed of an elastic body,
The linear vibration actuator according to claim 10, wherein the traveling wave generating means includes a piezoelectric element disposed on a surface of the slider and a drive control unit that applies a high-frequency voltage to the piezoelectric element.

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