JP2014023266A - Actuator and positioning device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an actuator capable of converting the bending force of an electrostriction element to other directions efficiently and stably, and to provide a positioning device using the same.SOLUTION: Two electrodes 12a, 12c are arranged on the upper surface of a planar electrostriction element 11 while spaced apart from each other, and two electrodes 12b, 12d are arranged on the lower surface of the electrostriction element 11, while spaced apart from each other, so as to face them across the electrostriction element 11. Furthermore, a movable element 13 is placed between the electrodes 12a, 12c arranged on the upper surface of the electrostriction element 11. When a voltage is applied so that the electrodes 12a, 12d become positive electrodes (+) and the electrodes 12b, 12c become negative electrodes (-), the electrostriction element 11 deforms in wave-shape between the adjoining electrodes, and the movable element 13 on the electrostriction element 11 inclines in a specified direction.

Description

  The present invention relates to an actuator and a positioning device using the actuator.

  Conventionally known actuators using electrostrictive elements that bend and deform when a voltage is applied are shown below. FIG. 13 is a perspective view showing a conventional actuator. As shown in FIG. 13A, the conventional actuator shown here includes a plate-shaped electrostrictive element 1 and a plurality of electrodes 2 provided on the upper and lower surfaces of the electrostrictive element 1. By applying a predetermined voltage to the electrode 2, as shown in FIGS. 13B and 13C, the electrostrictive element 1 can be curved or deformed into a wave shape. (See Patent Documents 1 and 2)

Japanese Patent No. 4646530 JP-A-5-76481

  Conventional actuators described in Patent Documents 1 and 2 include heart, bladder, gallbladder, stomach, lung, intestine, oral cavity, artificial organs such as diaphragm, angle adjusting device such as CCD camera and artificial eyeball, medical tube, etc. It is supposed that it can be used suitably for applications, but in any case, it is assumed that the bending force of the actuator is used as it is, and it is possible to convert the bending force of the actuator to another direction and use it. There is a problem that it is not assumed and is not suitable for applications where it is required. In addition, when converting the direction of force, it is a matter of course to perform the conversion efficiently and stably.

  The present invention has been made in view of the above-described problems, and provides an actuator capable of efficiently and stably converting the bending force of the actuator in another direction, and a positioning device using the actuator. The purpose is to do.

  An electrostrictive element, an electrode for applying a voltage to the electrostrictive element, and a mover disposed on the surface of the electrostrictive element, and a voltage is applied to the electrostrictive element via the electrode Thus, the actuator is configured such that the electrostrictive element is deformed into a wave shape, and the movable element is tilted by the inclination of the surface of the electrostrictive element accompanying the deformation.

  Two electrodes are disposed on the upper surface of the electrostrictive element so as to be spaced apart from each other, and two electrodes are disposed on the lower surface of the electrostrictive element so as to be spaced apart from each other. The movable element is disposed on the upper surface of the electrostrictive element. The actuator may be disposed between the two electrodes disposed.

  The electrode may be an actuator having a cylindrical shape and disposed in close contact with the electrostrictive element so that the longitudinal directions thereof are parallel to each other.

  The movable element includes a first movable element that tilts in a first direction and a second movable element that tilts in a second direction opposite to the first direction. And the second movable element can be an actuator configured to hold an object.

  The mover may be an actuator having a T-shape and a plane on the short side of the T-shape fixed to the surface of the electrostrictive element.

  The actuator may be a plurality of actuators formed on one electrostrictive element.

  The electrostrictive element can be an actuator made of a polymer gel material containing polyvinyl chloride, a plasticizer, and an ionic liquid.

  Any one of the above includes an actuator and a positioning jig having a concave portion for accommodating a positioning object, and the movable element of the actuator is disposed so as to face inward from the wall surface of the concave portion of the positioning jig. And a positioning device configured to tilt toward the inside of the recess.

  According to the present invention, the bending force of the electrostrictive element can be efficiently and stably converted in the direction intersecting with the bending force.

(A) Top view, (b) Bottom view, (c) Side view (Example 1) showing an embodiment of the actuator of the present invention. Side view showing the operation of the actuator of the present invention shown in FIG. (A) Top view showing an embodiment of the actuator of the present invention, (b) Bottom view (Example 2) (A) Top view showing an embodiment of the actuator of the present invention, (b) Bottom view (Example 3) (A) Top view, (b) Bottom view, (c) Side view (Example 4) showing an embodiment of the actuator of the present invention. Side view showing the operation of the actuator of the present invention shown in FIG. (A) Top view, (b) Bottom view, (c) AA sectional view (Example 5) showing an embodiment of the positioning device of the present invention. Sectional drawing which shows operation | movement of the positioning device of this invention shown in FIG. The top view which shows one Example of the positioning device of this invention (Example 6) The top view which shows operation | movement of the positioning device of this invention shown in FIG. The top view which shows one Example of the positioning device of this invention (Example 7) The top view which shows operation | movement of the positioning device of this invention shown in FIG. A perspective view showing a conventional actuator

  FIG. 1A is a top view and FIG. 1B is a side view showing an embodiment of the actuator of the present invention. The actuator of the present invention shown here includes a plate-shaped electrostrictive element 11, two electrodes 12 a and 12 c disposed on the upper surface of the electrostrictive element 11, and two electrodes 12 b disposed on the lower surface of the electrostrictive element 11. , 12d, and one movable element 13 disposed on the upper surface of the electrostrictive element 11.

  The electrostrictive element 11 includes a dielectric polymer such as polyvinyl chloride, a plasticizer such as adipic acid, sebacic acid, itaconic acid, and phthalic acid ester, and a gel made of an ionic liquid such as a phosphonium cation and an ammonium cation. Is formed into a flat plate having a thickness of about 0.3 mm. Polyvinyl chloride and the like are generally low in flexibility and hardly deform even if a voltage is applied as it is, but by adding a plasticizer and an ionic liquid at a predetermined ratio (for example, a dielectric polymer) : 1 to 50 parts by weight, plasticizer: 50 to 150 parts by weight, ionic liquid: 1 to 30 parts by weight). For a polymer gel material using a dielectric polymer such as polyvinyl chloride, see, for example, Japanese Patent Application Laid-Open No. 2009-273204.

  The four electrodes 12a, 12b, 12c, and 12d are made of metal and have a cylindrical shape with a diameter of about 0.8 mm, and are arranged in close contact with the surface of the electrostrictive element 11 so that their longitudinal directions are parallel to each other. Has been. Of the four electrodes 12a, 12b, 12c, and 12d, the electrodes 12a and 12b are disposed to face each other with the electrostrictive element 11 in between, and form an electrical pair with each other. 12d are arranged opposite to each other with the electrostrictive element 11 interposed therebetween, and form an electrical pair with each other, and are respectively connected to a power supply device (not shown).

  The mover 13 is formed by molding a resin in a T shape, and the T side of the short side of the T shape extends in a direction perpendicular to the surface of the electrostrictive element 11. It is fixed to the surface of the electrostrictive element 11 located approximately at the center between the electrode 12a and the electrode 12c via an adhesive or the like. If the mover 13 is T-shaped, the adhesion area to the electrostrictive element 11 can be increased while suppressing an increase in weight as compared with a simple rod-shaped element, and the center of gravity can be increased. 11, the movable element 13 can be stably fixed to the surface of the electrostrictive element 11.

  FIG. 2 is a side view showing the operation of the actuator of the present invention shown in FIG. FIG. 2A shows an initial state in which the driving voltage is not supplied to the actuator and the electrostrictive element 11 is flat. When the actuator is driven from this state, FIG. As shown, among the four electrodes 12a, 12b, 12c, 12d, a predetermined voltage is applied so that the electrodes 12a, 12d are positive (+) and the electrodes 12b, 12c are negative (-).

  Since the polymer gel material mainly composed of polyvinyl chloride constituting the electrostrictive element 11 has a property of bending toward the positive electrode (+) side, the electrostrictive element 11 includes the electrode 12a that is the positive electrode (+), It bends to the 12d side and is in a state of being deformed into a wave shape when viewed macroscopically. At this time, since the electrostrictive element 11 bends smoothly while being in close contact with the outer peripheral surfaces of the columnar electrodes 12a and 12d, the electrodes 12a and 12d are larger than the case where the cross section such as a prismatic shape is square. Not only is the amount of bending obtained, but no excessive stress or load is applied to the electrostrictive element 11.

  When the electrostrictive element 11 is deformed in a wave shape as described above, the upper surface of the electrostrictive element 11 is inclined so that the electrode 12c side is downward in the region between the electrode 12a and the electrode 12c. The movable element 13 fixed on the upper surface of the strain element 11 is inclined with its tip approaching the electrode 12c. Here, the direction in which the movable element 13 is inclined is a direction that intersects the direction in which the electrostrictive element 11 bends. Therefore, if the tip of the movable element 13 is used as a force application point, the electrostrictive element 11 is generated. The direction of the force to be converted has been changed to the direction intersecting it. Further, the conversion is performed efficiently and stably because the configuration of the actuator of the present invention is a simple one in which the movable element 13 is fixed to the surface of the electrostrictive element 11.

  When the mover 13 is tilted from the state shown in FIG. 2B to the opposite side, as shown in FIG. 2C, of the four electrodes 12a, 12b, 12c, and 12d, the electrodes 12a and 12d are A predetermined voltage is applied by reversing the polarity so that the negative electrode (−) and the electrodes 12b and 12c become the positive electrode (+).

  Then, the electrostrictive element 11 bends toward the electrodes 12b and 12c, which are the positive electrodes (+), and deforms into a wave shape having a phase shifted by 180 ° from the state shown in FIG. Along with this, the movable element 13 is inclined with its tip approaching the electrode 12a. As shown in FIG. 2B, if the tilted movable element 13 is simply returned to the initial state without tilting, the application of the voltage to each electrode is stopped and the electrostrictive element 13 is self-restored. It is also possible to return to the initial state using force.

  FIG. 3A is a top view and FIG. 3B is a bottom view showing an embodiment of the actuator of the present invention. In this embodiment, a plurality of the actuators according to the present invention shown in FIG. 1 are arranged in a plane in a 2 × 2 matrix. In this embodiment, the electrostrictive element 11 constituting the actuator is individually provided for each actuator. However, the electrodes 12a, 12b, 12c, and 12d extend between two actuators arranged in the vertical direction. And are shared between the two actuators. The electrodes 12a, 12b, 12c, and 12d are connected to a common power supply device. By applying a predetermined voltage to the electrodes 12a, 12b, 12c, and 12d from the power supply device at a time, the actuators simultaneously perform the same operation. Then, all the movers 13 tilt in the same direction.

  In addition, the connection form of each electrode and the power supply device is not limited to this. For example, an independent electrode and power supply device are provided for each actuator, and each actuator is operated differently, or a plurality of actuators are provided. It is also possible to divide every predetermined number and provide an independent electrode and power supply device for each division, and to perform different operations for each division.

  FIG. 4A is a top view and FIG. 4B is a bottom view showing an embodiment of the actuator of the present invention. In this embodiment, a plurality of electrostrictive elements 11 provided individually for each actuator in the second embodiment shown in FIG. 3 are replaced with one large-sized one and shared among the actuators. In this configuration, since there is only one electrostrictive element 11, the configuration can be simplified.

  5A is a top view, FIG. 5B is a bottom view, and FIG. 5C is a side view showing an embodiment of the actuator of the present invention. In this embodiment, three electrodes 12 a, 12 c, and 12 e and two movable elements (first movable element 13 a and second movable element 13 b) are provided on the upper surface of the electrostrictive element 11, and the lower surface of the electrostrictive element 11 is provided. Three electrodes 12b, 12d, and 12f are provided.

  The six electrodes 12a, 12b, 12c, 12d, 12e, and 12f are arranged so that their longitudinal directions are parallel to each other, and the three electrodes 12a, 12c, and 12e provided on the upper surface of the electrostrictive element 11; The three electrodes 12b, 12d, and 12f provided on the lower surface of the electrostrictive element 11 are opposed to each other with the electrostrictive element 11 interposed therebetween, and form an electrical pair with each other. The first movable element 13a and the second movable element 13b are fixed to the surface of the electrostrictive element 11 positioned between the electrode 12a and the electrode 12c and between the electrode 12c and the electrode 12e, respectively.

  FIG. 6 is a side view showing the operation of the actuator of the present invention shown in FIG. FIG. 6A shows an initial state where the driving voltage is not supplied to the actuator and the electrostrictive element 11 is flat. When the actuator is driven from this state, the six electrodes 12a and 12b are shown. , 12c, 12d, 12e, and 12f, a predetermined voltage is applied so that the electrodes 12a, 12d, and 12e are positive (+) and the electrodes 12b, 12c, and 12f are negative (-).

  Then, as shown in FIG. 6B, the electrostrictive element 11 has a phase opposite to each other in the region between the electrode 12a and the electrode 12c and the region between the electrode 12c and the electrode 12e. Along with this, the first movable element 13a disposed between the electrode 12a and the electrode 12c and the second movable element 13b disposed between the electrode 12c and the electrode 12e, respectively, The tip is inclined toward the electrode 12c side. Here, since the first movable element 13a and the second movable element 13b operate so that the distal ends thereof are close to each other, for example, the distal ends of the first movable element 13a and the distal end of the second movable element 13b are used. It is possible to hold a certain object. In this case, the distance between the first movable element 13a and the second movable element 13b and the length of each of the first movable element 13a and the second movable element 13b are appropriately selected within a range in which the object can be appropriately gripped by the tip of each other when tilted. It ’s fine.

  When the first movable element 13a and the second movable element 13b are tilted from the state shown in FIG. 6 (b) to the opposite side, as shown in FIG. 6 (c), the six electrodes 12a, 12b, 12c , 12d, 12e, and 12f, a predetermined voltage is applied by reversing the polarity so that the electrodes 12a, 12d, and 12e are negative (−) and the electrodes 12b, 12c, and 12f are positive (+). .

  Then, the electrostrictive element 11 is bent toward the electrodes 12b, 12c, and 12f that are the positive electrodes (+), and viewed in a macroscopic manner, the electrostrictive element 11 has a wave shape in which the phase is shifted by 180 ° from the state illustrated in FIG. Accordingly, the first movable element 13a and the second movable element 13b are inclined with their tips approaching the electrodes 12a and 12e, respectively. In addition, as shown in FIG. 6B, if the first movable element 13a and the second movable element 13b that are inclined are simply returned to the initial state without inclination, all the voltages are applied to the respective electrodes. It is also possible to stop and return to the initial state using the self-restoring force of the electrostrictive element 11.

  While the actuator of the present invention has been described with reference to some embodiments, the electrostrictive element 11 in the actuator of the present invention is not limited to a polymer gel material using a dielectric polymer such as polyvinyl chloride, It may be a polymer gel material using a dielectric polymer other than polyvinyl chloride, or any other material that does not use a dielectric polymer. Any material may be used without departing from the spirit of the invention.

  In addition, the electrode for applying a voltage to the electrostrictive element 11 is not necessarily arranged in close contact with the electrostrictive element 11, and a voltage large enough to deform the electrostrictive element 11 can be applied. If there is, it may be arranged away from the electrostrictive element 11. Furthermore, the material constituting the electrode is not limited to a metal, and various other materials can be appropriately selected as long as it is a conductive material. The shape of the electrode is not limited to a cylindrical shape, but is a polygonal column or a thin film. The shape and the like can be selected as appropriate.

  The position where the movable element 13, the first movable element 13a, and the second movable element 13b are installed is not limited to between adjacent electrodes, and the surface of the electrostrictive element 11 is inclined due to deformation of the electrostrictive element 11. It may be anywhere as long as it is within the generated region, and the installation angle and orientation can be selected as appropriate. Furthermore, there is no restriction | limiting in particular also about the material and shape which comprise them, About a shape, not only T shape but various things, such as L shape, rod shape, flat plate shape, can be selected suitably.

  FIG. 7A is a top view and FIG. 7B is a cross-sectional view taken along line AA, showing an embodiment of the positioning device of the present invention. However, in FIG. 7B, the actuator portion is a side view. The positioning device shown here uses the actuator of the present invention shown in FIG. 1 as a drive source, and includes the actuator of the present invention shown in FIG. 1 and a positioning jig 21 installed above the actuator. Has been. The positioning jig 21 is a flat plate made of metal, resin, or the like, and is provided with a recess 22 for accommodating a positioning object on the surface (upper surface) opposite to the actuator. Here, assuming that the positioning object is a rectangular parallelepiped, the recess 22 is formed as a substantially rectangular parallelepiped space having an inner diameter dimension slightly larger than the outer dimension of the positioning object.

  An opening 23 penetrating the positioning jig 21 is provided in a part of the wall surface and the bottom surface of the recess 22, and the actuator movable element 13 installed below the positioning jig 21 is provided through the opening 23. It protrudes. The movable element 13 protruding from the opening 23 is located outside the wall surface of the recess 22 in an initial state where the mover 13 is not inclined, and the tip is retracted from the inside to the outside of the recess 22.

  FIG. 8 is a sectional view showing the operation of the positioning device of the present invention shown in FIG. When positioning the rectangular parallelepiped positioning object 24 using the positioning device of the present invention shown in FIG. 7, first, as shown in FIG. The positioning object 21 is retracted to the outside of the recess 22, and the positioning object 24 is accommodated in the recess 22 of the positioning jig 21 in this state. At this time, the positioning object 24 accommodated in the recess 22 is in a state in which it can move freely in the recess 22 within the range of the difference between the outer dimension and the inner diameter of the recess.

  Here, before accommodating the positioning object 24 in the recess 22, the driving of the actuator is stopped to retract the mover 13 to the outside of the recess 22, but the actuator is driven to move the mover 13. You may make it retract | save by making it incline to the opposite side to the recessed part 22. FIG.

  When the accommodation of the positioning object 24 in the recess 22 is completed, the actuator 13 is driven to incline the mover 13 toward the positioning object 24 as shown in FIG. Then, the side end of the mover 13 comes into contact with the side end of the positioning object 24 and the positioning object 24 is pressed against the wall surface on the opposite side of the recess 22 as it is, so that the positioning object 24 is recessed in the longitudinal direction. It will be in the state positioned in the predetermined position in 22.

  In the positioning device of the present invention, since a flexible and stable force generated by deformation of the electrostrictive element 11 is used as a driving force, for example, even if the positioning object 24 is a brittle material such as quartz, the positioning object Positioning can be performed reliably without damaging the object 24.

  FIG. 9 is a top view showing an embodiment of the positioning device of the present invention. This embodiment has the same basic configuration as that of the fifth embodiment shown in FIG. 7. As a characteristic configuration, the recess 22 of the positioning jig 21 has two openings 23 through which the actuator mover 13 is inserted. One of the movable elements 13 of the actuator protrudes upward from the two openings 23 one by one. One of the two openings 23 is provided at the center of the short side of the recess 22, and the movable element 13 protruding therefrom is configured to tilt in a direction perpendicular to the short side of the recess 22. Thus, the other of the two openings 23 is provided at the center of the long side of the recess 22, and the movable element 13 protruding therefrom is configured to tilt in a direction orthogonal to the long side of the recess 22.

  FIG. 10 is a top view showing the operation of the positioning device of the present invention shown in FIG. When positioning the positioning object 24, first, the actuator is stopped or driven to retract the two movable elements 13 to the outside of the recess 22, respectively, and the positioning object 24 is accommodated in the recess 22 in that state. Thus, the actuator is driven so that the two movable elements 13 are simultaneously or sequentially inclined toward the inside of the recess 22 so that the side ends of the two movable elements 13 are brought into contact with the side ends of the positioning object 24, respectively. Then, the positioning object 24 is pressed against the wall surface of the concave portion 22 on the side facing the mover 13, and as shown in FIG. 9, the positioning object 24 is positioned at the same time in the longitudinal direction and the short direction. Become.

  FIG. 11 is a top view showing an embodiment of the positioning device of the present invention. The present embodiment has the same basic configuration as that of the fifth embodiment shown in FIG. 7, and as a characteristic configuration, an opening 23 for inserting the movable element 13 of the actuator is provided at the corner of the recess 22. Then, the movable element 13 of the actuator protrudes upward therefrom, and is tilted from the corner portion having the opening 23 toward the corner portion on the opposite side thereof.

  FIG. 12 is a top view showing the operation of the positioning device of the present invention shown in FIG. When positioning the positioning object 24, first, the actuator is stopped or driven to retract the movable element 13 to the outside of the recess 22, and the positioning object 24 is accommodated in the recess 22 in this state, and then the actuator Is driven to incline the movable element 13 toward the inside of the recess 22, and the side end of the movable element 13 is brought into contact with the corner side end of the positioning object 24. Then, the positioning object 24 is pressed against the corner of the concave portion 22 on the side facing the movable element 13, and the positioning object 24 is positioned at the same time in the longitudinal direction and the short direction as shown in FIG. It becomes.

  In this embodiment, the positioning object 24 is simultaneously positioned in the longitudinal direction and the lateral direction without providing two actuators for one positioning object 24 as in the sixth embodiment shown in FIG. Can do.

  The positioning device of the present invention has been described with reference to several embodiments. However, in the positioning device of the present invention, the positioning jig 21 is provided with a plurality of recesses 22 for accommodating the positioning object 24, A plurality of openings 23 and a plurality of actuators may be provided corresponding to the recesses 22.

  Further, the actuator may be incorporated in the positioning jig 21 if the structure permits. Anyway, the actuator should just be arrange | positioned so that the needle | mover may face inward from the wall surface of the recessed part 22 provided in the positioning jig 21. FIG.

  Further, the shape of the concave portion 22 provided in the positioning jig 21 may be appropriately changed according to the outer shape of the positioning object 24.

  The actuator of the present invention is suitable for an application for moving a small-sized article such as a small electronic component by a minute distance, but is not limited thereto, and can be applied to various applications.

DESCRIPTION OF SYMBOLS 1 Electrostrictive element 2 Electrode 11 Electrostrictive element 12a Electrode 12b Electrode 12c Electrode 12d Electrode 12e Electrode 12f Electrode 13 Movable element 13a First movable element 13b Second movable element 21 Positioning jig 22 Recessed part 23 Opening part 24 Positioning object

Claims (8)

An electrostrictive element;
An electrode for applying a voltage to the electrostrictive element;
A mover disposed on the surface of the electrostrictive element;
When the voltage is applied to the electrostrictive element via the electrode, the electrostrictive element is deformed in a wave shape, and the movable element is tilted by the inclination of the surface of the electrostrictive element accompanying the deformation. An actuator characterized by comprising:   Two electrodes are disposed on the upper surface of the electrostrictive element so as to be spaced apart from each other, and two electrodes are disposed on the lower surface of the electrostrictive element so as to be spaced apart from each other. The movable element is disposed on the upper surface of the electrostrictive element. The actuator according to claim 1, wherein the actuator is arranged between the two arranged electrodes.   The actuator according to claim 2, wherein the electrode has a cylindrical shape and is disposed in close contact with the electrostrictive element so that the longitudinal directions thereof are parallel to each other.   The movable element includes a first movable element that tilts in a first direction and a second movable element that tilts in a second direction opposite to the first direction. The actuator according to any one of claims 1 to 3, wherein the actuator is configured to grip an object with the second movable element.   5. The mover according to claim 1, wherein the mover has a T shape, and a plane on a short side of the T shape is fixed to a surface of the electrostrictive element. Actuator.   The actuator according to claim 1, wherein a plurality of the actuators are formed in one electrostrictive element.   The actuator according to any one of claims 1 to 6, wherein the electrostrictive element is made of a polymer gel material containing polyvinyl chloride, a plasticizer, and an ionic liquid. An actuator according to any one of claims 1 to 7;
A positioning jig having a recess for accommodating a positioning object;
A positioning device, wherein the mover of the actuator is arranged so as to face inward from the wall surface of the concave portion of the positioning jig, and is tilted toward the inner side of the concave portion.

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