WO2018055972A1 - Actuator device - Google Patents

Abstract

The actuator device (10) is provided with an actuator member (21, 22), an operated portion (30), a driving unit, and a tensile-force-applying unit (50). The actuator member deforms in response to externally applied energy. The operated portion is coupled to the actuator member. The driving unit displaces the operated portion in the deformation direction of the actuator member by applying energy to the actuator member. The tensile-force-applying unit provides the actuator member with tensile force by which tensile-force change based on at least one of expansion and contraction of the actuator member caused by natural deformation can be corrected.

Description

Actuator device Cross-reference of related applications

This application is based on Japanese Patent Application No. 2016-183297 filed on September 20, 2016, and Japanese Patent Application No. 2017-0665134 filed on March 29, 2017, Claims the benefit of that priority, the entire contents of which patent application is incorporated herein by reference.

This disclosure relates to an actuator device that uses, as a power source, an actuator member that deforms in response to external energy input by electrical, photonic, chemical, thermal, absorption, or other means.

Conventionally, an actuator member described in Patent Document 1 is known as this type of actuator member. The actuator member described in Patent Document 1 is made of a polymer fiber and has a characteristic of being twisted or stretched by a temperature change based on electric heating or white heating.

JP 2016-42783 A

When the actuator member described in Patent Document 1 is once heated and then naturally cooled, the actuator member is deformed in a direction opposite to the deformation direction during heating. Therefore, when the actuated part is connected to the actuator member described in Patent Document 1 and then the actuator member is heated and cooled, the actuated part can be reciprocated.

On the other hand, an actuator member made of a polymer fiber as described in Patent Document 1 can change in deformation characteristics such as torsional characteristics and stretch characteristics by absorbing and swelling water and oil in the surrounding environment. Similarly, when the actuator member is deformed by a constant load applied to the actuator member, so-called creep deformation occurs in the actuator member, the deformation characteristics of the actuator member can be similarly changed. If the actuator member deforms due to swelling, creep deformation, thermal expansion, or thermal contraction, the operation of the operated part connected to the actuator member also changes, and as a result, the operation of the operated part may be destabilized. is there.

Such a problem is not limited to an actuator member made of a polymer fiber, but is applied to an actuator device that uses, as a power source, an actuator member that can change its deformation characteristics due to natural deformation such as swelling, creep deformation, thermal expansion, and thermal contraction This is a common issue.

An object of the present disclosure is to provide an actuator device that can stabilize the operation of an actuated portion under a situation where natural deformation occurs in an actuator member.

The actuator device according to one aspect of the present disclosure includes an actuator member, an actuated portion, a driving portion, and a tension applying portion. The actuator member is deformed in response to external energy application. The actuated part is connected to the actuator member. The drive unit applies energy to the actuator member to displace the operated portion in the deformation direction of the actuator member. The tension applying unit applies a tension that can correct a change in tension based on at least one of expansion and contraction of the actuator member due to natural deformation to the actuator member.

According to this configuration, even under a situation where the actuator member performs at least one of expansion and contraction due to natural deformation, the tension change of the actuator member is corrected by the tension applied to the actuator member from the tension applying unit. Thereby, since the influence which at least one of expansion | extension and contraction of the actuator member by natural deformation has on the action | operation of a to-be-actuated part can be relieve | moderated, the action | operation of an to-be-actuated part can be stabilized.

FIG. 1 is a diagram schematically showing the structure of the actuator device according to the first embodiment. FIG. 2 is a block diagram illustrating an electrical configuration of the actuator device according to the first embodiment. FIG. 3 is a diagram schematically illustrating an operation example of the actuator device according to the first embodiment. FIG. 4 is a diagram schematically showing the structure of the actuator device according to the second embodiment. FIG. 5 is an enlarged view showing an example of the correcting actuator member in the actuator device of the second embodiment. FIG. 6 is a block diagram illustrating an electrical configuration of the actuator device according to the second embodiment. FIG. 7 is an enlarged view showing the correcting actuator member in the actuator device according to the modification of the second embodiment. FIG. 8 is a diagram schematically showing the structure of the actuator device according to the third embodiment. FIG. 9 is a diagram schematically illustrating the structure of an actuator device according to a first modification of the third embodiment. FIG. 10 is a diagram schematically illustrating the structure of an actuator device according to a second modification of the third embodiment. FIG. 11 is a diagram schematically showing the structure of the actuator device of the fourth embodiment. FIG. 12 is a diagram schematically showing the structure of an actuator device according to a modification of the fourth embodiment. FIG. 13 is a diagram schematically illustrating the relationship between the central axis m1 of the first actuator member and the central axes m10 and m11 of the coil spring in the actuator device according to the fourth embodiment. FIG. 14 is a diagram schematically showing the relationship between the central axis m1 of the first actuator member and the central axes m10 to m12 of the coil spring in the actuator device of the fourth embodiment. FIG. 15 is a diagram schematically illustrating the structure of an actuator device according to another embodiment.

<First Embodiment>
Hereinafter, a first embodiment of an actuator device will be described with reference to the drawings. In order to facilitate the understanding of the description, the same constituent elements in the drawings will be denoted by the same reference numerals as much as possible, and redundant description will be omitted.

As shown in FIG. 1, the actuator device 10 of the present embodiment includes a first actuator member 21, a second actuator member 22, an actuated portion 30, a fixing member 40, and a tension applying device 50. Yes.

The first actuator member 21 and the second actuator member 22 are arranged in series with the actuated portion 30 in between. Each actuator member 21 and 22 consists of a wire-shaped member arrange | positioned along the axis line m1. Each actuator member 21 and 22 is formed of polymer fibers such as polyamide. On the surface of each actuator member 21, 22, metal plating such as silver is formed. The actuator members 21 and 22 can be heated by passing a current through the metal plating formed on the surfaces of the actuator members 21 and 22. Each actuator member 21, 22 has a characteristic of being torsionally deformed about the axis m 1 based on the supply of heat energy called heating.

Specifically, as shown by a two-dot chain line in the figure, the orientation direction of the polyamide molecule that is a constituent molecule of the first actuator member 21 is centered on the axis line m1 in a manner inclined at a predetermined angle with respect to the axis line m1. It has a spiral shape. As a result, the first actuator member 21 is torsionally deformed in the first direction R11 centered on the axis m1 based on the application of thermal energy by heating, and is cooled by natural cooling or the like, thereby being opposite to the first direction R11. And torsionally deform in the direction of. That is, the deformation direction of the first actuator member 21 is the first direction R11.

On the other hand, the orientation direction of the polyamide molecule that is the constituent molecule of the second actuator member 22 is set to the axis m1 in a manner that it is inclined at a predetermined angle in the direction opposite to the orientation direction of the constituent molecule of the first actuator member 21 with respect to the axis m1. It has a spiral shape in the center. As a result, the second actuator member 22 is torsionally deformed in the second direction R12 opposite to the first direction R11 based on the application of thermal energy by heating, and is cooled by natural cooling or the like, thereby being changed into the second direction R12. Has the property of torsional deformation in the opposite direction. That is, the deformation direction of the second actuator member 22 is the second direction R12. The cross-sectional shape and length of the second actuator member 22 are the same as the cross-sectional shape and length of the first actuator member 21.

In the following figures, illustration of the orientation direction of the actuator member is omitted unless otherwise specified.

The actuated part 30 is connected to one end part 21 a of the first actuator member 21. Therefore, when the first actuator member 21 is torsionally deformed in the first direction R11 by heating, a rotational force in the first direction R11 is applied to the operated part 30, so that the operated part 30 is rotationally displaced in the first direction R11. To do.

The actuated portion 30 is also connected to one end portion 22 a of the second actuator member 22. Therefore, when the second actuator member 22 is torsionally deformed in the second direction R12 by heating, a rotational force in the second direction R12 is applied to the operated part 30, so that the operated part 30 is rotationally displaced in the second direction R12. To do.

A sensor device 31 is fixedly provided on the operated part 30. The sensor device 31 is a device that detects a required physical quantity, an imaging device, or the like. The sensor device 31 is rotationally displaced in the first direction R11 and the second direction R12 together with the operated part 30. The actuated portion 30 is supported by a support mechanism (not shown) so as to be rotatable about the axis m1.

The fixing member 40 is a housing of the actuator device 10 or the like. An end 22b opposite to the end 22a connected to the operated part 30 in the second actuator member 22 is fixedly attached to the fixing member 40. The fixing member 40 holds the second actuator member 22.

The tension applying device 50 is a device that applies tension to the actuator members 21 and 22 based on energization. The tension applying device 50 has a movable part 51. The movable portion 51 is connected to an end portion 21 b opposite to the end portion 21 a connected to the operated portion 30 in the first actuator member 21. The tension applying device 50 displaces the movable portion 51 in the direction indicated by the arrow A1 based on energization. The direction indicated by the arrow A <b> 1 is a direction parallel to the axis m <b> 1 and a direction away from the operated part 30. Due to the displacement of the movable portion 51, a tension in the direction indicated by the arrow A1 is applied to each actuator member 21, 22. Further, the tension applied to each actuator member 21, 22 can be adjusted by adjusting the energization amount to the tension applying device 50. Thus, the tension applying device 50 can electrically control the tension applied to each actuator member 21, 22. As such a tension | tensile_strength provision apparatus 50, the electromagnetic actuator apparatus which displaces the movable part 51 by electromagnetic force, for example, and the motor apparatus which displaces the movable part 51 using the rotational force of a rotor can be used.

Note that the tension applying device 50 holds the first actuator member 21. The tension applying device 50 and the fixing member 40 also have a function of holding the operated part 30 via the actuator members 21 and 22.

Next, the electrical configuration of the actuator device 10 will be described.
As shown in FIG. 2, the actuator device 10 further includes a first heating unit 61, a second heating unit 62, and a control unit 70.

The first heating unit 61 heats the first actuator member 21 with Joule heat by passing a current through the metal plating of the first actuator member 21. Thereby, the actuated part 30 is rotationally displaced in the first direction R11 by the first actuator member 21 being torsionally deformed in the first direction R11. Thus, the 1st heating part 61 of this embodiment is functioning as a drive part which displaces the to-be-acted part 30 in the deformation | transformation direction of the 1st actuator member 21 by providing energy to the 1st actuator member 21. .

The second heating unit 62 heats the second actuator member 22 with Joule heat by passing a current through the metal plating of the second actuator member 22. Thereby, the actuated part 30 is rotationally displaced in the second direction R12 by the second actuator member 22 being twisted and deformed in the second direction R12. Thus, the second heating unit 62 of the present embodiment functions as a drive unit that displaces the actuated unit 30 in the deformation direction of the second actuator member 22 by applying energy to the second actuator member 22. .

The control unit 70 heats the first actuator member 21 and the second actuator member 22 via the first heating unit 61 and the second heating unit 62, respectively, so that the first direction R11 and the second direction R12 of the operated unit 30 are achieved. This is a part that executes posture control for changing the posture of the robot. The control unit 70 is configured around a microcomputer having a CPU, ROM, RAM, and the like. The CPU executes a calculation process related to the attitude control of the operated part 30. The ROM stores programs and data necessary for attitude control. In the RAM, CPU calculation results and the like are temporarily stored.

Specifically, the control unit 70 heats the first actuator member 21 via the first heating unit 61 when the attitude of the actuated unit 30 is displaced in the first direction R11. The control unit 70 heats the second actuator member 22 via the second heating unit 62 when the attitude of the operated unit 30 is displaced in the second direction R12.

Further, the control unit 70 applies tension to the actuator members 21 and 22 by controlling the tension applying device 50. Specifically, the control unit 70 energizes the tension applying device 50 when starting the attitude control of the operated unit 30, that is, when starting the operation of the operated unit 30. As a result, the tension applying device 50 is driven, and a predetermined tension is applied to each actuator member 21, 22. The control unit 70 drives the tension applying device 50 immediately before the start of the attitude control of the actuated unit 30, that is, immediately before the start of the operation of the actuated unit 30, thereby causing each actuator member 21, 22 to move. A predetermined tension may be applied. The controller 70 maintains a state in which a predetermined tension is applied to each actuator member 21, 22 by maintaining energization to the tension applying device 50 during the period during which the attitude control of the actuated part 30 is executed. To do.

Further, the control unit 70 is applied to each actuator member 21 and 22 by stopping energization of the tension applying device 50 at the end of the posture control of the operated unit 30, that is, at the end of the operation of the operated unit 30. Release the tension.

Next, an operation example of the actuator device 10 of the present embodiment will be described.
Under the situation where natural deformation such as swelling, creep deformation, thermal expansion, etc. occurs in each actuator member 21, 22, when each actuator member 21, 22 extends in the direction B along the axis m1 shown in FIG. As shown, the actuator members 21 and 22 may bend. Hereinafter, the direction indicated by the arrow B is also referred to as the extending direction of the actuator members 21 and 22 based on natural deformation. When the actuator members 21 and 22 extend due to natural deformation, the rotational force based on the torsional deformation of the actuator members 21 and 22 is not easily applied to the actuated portion 30. This becomes a factor that destabilizes the operation of the operated part 30.

In this regard, in the actuator device 10 of the present embodiment, even when the actuator members 21 and 22 extend in the direction along the axis m1 due to natural deformation, at the time of starting the posture control of the actuated unit 30 or immediately before it, The tension in the direction indicated by the arrow A1 is applied from the tension applying device 50 to the first actuator member 21 and the second actuator member 22. Since the tension changes due to the extension of the first actuator member 21 and the second actuator member 22 due to natural deformation are corrected by this tension, the extension state of the first actuator member 21 and the second actuator member 22 is shown in FIG. It is possible to return to the state that is. Thereby, since the rotational force based on the torsional deformation of each actuator member 21 and 22 is appropriately given to the operated part 30, it becomes easy to operate the operated part 30 appropriately.

According to the actuator device 10 of the present embodiment described above, the operations and effects shown in the following (1) to (3) can be obtained.

(1) Even under a situation where the actuator members 21 and 22 extend in the direction along the axis m1 due to natural deformation, the actuator members 21 are applied by the tension applied from the tension applying device 50 to the actuator members 21 and 22. , 22 is corrected for tension change. Thereby, since the influence which the expansion | extension of each actuator member 21 and 22 by natural deformation has on the action | operation of the to-be-actuated part 30 can be relieve | moderated, the action | operation of the to-be-actuated part 30 can be stabilized.

(2) The tension applying device 50 applies tension to the actuator members 21 and 22 at the start of the operation of the actuated portion 30 or immediately before the operation. Further, the tension applying device 50 releases the tension applied to each actuator member 21, 22 when the operation of the operated part 30 is stopped or immediately after that. Thereby, since the stress given to each actuator member 21 and 22 is relieved in periods other than the period in which the to-be-actuated part 30 is act | operating, the time-dependent deterioration of each actuator member 21 and 22 can be suppressed.

(3) The tension applying device 50 is used as a tension applying unit that can electrically control the tension applied to each actuator member 21, 22. Thereby, the magnitude | size of the tension | tensile_strength given to each actuator member 21 and 22 and the provision timing of tension | tensile_strength can be arbitrarily adjusted by controlling the energization amount and energization timing of the tension | tensile_strength provision apparatus 50.

Second Embodiment
Next, a second embodiment of the actuator device 10 will be described. Hereinafter, the difference from the first embodiment will be mainly described.

As shown in FIG. 4, the actuator device 10 of this embodiment includes a correction actuator member 23 instead of the tension applying device 50. The correction actuator member 23 is formed of a wire-like member disposed along the axis m1. One end 23 a of the correction actuator member 23 is connected to the end 21 b of the first actuator member 21. The other end 23b of the correcting actuator member 23 is fixedly attached to a fixing member 41 such as a housing. The fixing member 41 holds the correcting actuator member 23. The fixing members 40 and 41 also have a function of holding the actuated portion 30 via the actuator members 21 and 22 and the correction actuator member 23.

The straightening actuator member 23 is formed of a bundle of polymer fibers such as polyamide. The correction actuator member 23 is formed integrally with the first actuator member 21. The correcting actuator member 23 may be a separate body from the first actuator member 21. In this case, the correcting actuator member 23 is joined to the first actuator member 21 by bonding or the like.

A metal plating such as silver is formed on the surface of the straightening actuator member 23. The metal plating of the correction actuator member 23 and the metal plating of the first actuator member 21 are electrically insulated, and current is applied to either the metal plating of the correction actuator member 23 or the metal plating of the first actuator member 21. It is possible to flow. By applying a current to the metal plating formed on the surface of the correction actuator member 23, the correction actuator member 23 is heated. The correcting actuator member 23 has a characteristic of contracting in the direction B along the axis m1 based on application of thermal energy called heating.

Specifically, as shown in FIG. 5, the correcting actuator member 23 has a structure in which polymer fibers in which the arrangement direction of constituent molecules is helical are arranged in a spiral shape around the axis m1. The polymer fiber constituting the straightening actuator member 23 has a characteristic of contracting by heating. Due to the contraction of the polymer fiber, the correction actuator member 23 as a whole contracts in the direction B along the axis m1. Due to the contraction of the correcting actuator member 23 in the direction B along the axis m1, a tension in the direction indicated by the arrow A1 is applied to each actuator member 21, 22. Further, since the amount of contraction of the correction actuator member 23 can be adjusted by adjusting the heating amount of the correction actuator member 23, the tension applied to each actuator member 21, 22 can be adjusted as a result. Can do.

Next, the electrical configuration of the actuator device 10 of the present embodiment will be described.
As shown in FIG. 6, the actuator device 10 further includes a third heating unit 63. The third heating unit 63 heats the correction actuator member 23 with Joule heat by passing a current through the metal plating of the correction actuator member 23. As a result, the correction actuator member 23 contracts, so that tension is applied to the actuator members 21 and 22. As described above, the third heating unit 63 of the present embodiment functions as a correction driving unit that applies energy to the correction actuator member 23.

The control unit 70 applies tension to the actuator members 21 and 22 by contracting the correcting actuator member 23 via the third heating unit 63. Specifically, the control unit 70 applies tension to each actuator member 21, 22 by heating the correction actuator member 23 at the start of attitude control of the operated unit 30, that is, at the start of operation of the operated unit 30. Is granted. The controller 70 heats the actuator member 23 for correction immediately before the start of the attitude control of the actuated part 30, that is, immediately before the start of the operation of the actuated part 30. A predetermined tension may be applied to the. The controller 70 maintains the state in which the predetermined tension is applied to the actuator members 21 and 22 by maintaining the heating of the correcting actuator member 23 during the period during which the attitude control of the actuated portion 30 is being performed. To do.

Further, the control unit 70 is applied to each actuator member 21 and 22 by stopping the heating of the correcting actuator member 23 at the end of the attitude control of the operated unit 30, that is, at the end of the operation of the operated unit 30. Release the tension.

According to the actuator device 10 of the present embodiment described above, the same or similar actions and effects as the above (1) and (2) according to the first embodiment can be obtained, and are shown in the following (4). Functions and effects can be obtained.

(4) The straightening actuator member 23 and the third heating unit 63 are used as a tension applying unit capable of electrically controlling the tension applied to each actuator member 21, 22. Thereby, by controlling the heating amount and heating timing of the correcting actuator member 23, the magnitude of the tension applied to each actuator member 21, 22 and the timing of applying the tension can be arbitrarily adjusted.

(Modification)
Next, a modified example of the actuator device 10 of the second embodiment will be described. Hereinafter, the description will focus on differences from the actuator device 10 of the second embodiment.

In the actuator device 10 of this modification, the correcting actuator member 23 has a structure as shown in FIG. That is, the correction actuator member 23 is disposed along the axis m1. As indicated by the two-dot chain line in the figure, the orientation direction of the polyamide molecules, which are the constituent molecules of the correcting actuator member 23, is helical with the axis m1 as the center. The spiral angle in the orientation direction of the correcting actuator member 23 with respect to the axis m1 is larger than the spiral angle in the orientation direction of the first actuator member 21 with respect to the axis m1. Accordingly, when the polymer fiber constituting the correction actuator member 23 contracts by heating, the correction actuator member 23 as a whole contracts in the direction along the axis m1. By contraction of the correcting actuator member 23 in the direction along the axis m1, tension in the direction indicated by the arrow A1 can be applied to each actuator member 21, 22.

Even with such a correcting actuator member 23, the same or similar actions and effects as the above (1), (2), and (4) according to the second embodiment can be obtained.

<Third Embodiment>
Next, a third embodiment of the actuator device 10 will be described. Hereinafter, the description will focus on the differences from the actuator device 10 of the first embodiment.

As shown in FIG. 8, the actuator device 10 of this embodiment has an elastic member 80 instead of the tension applying device 50. The elastic member 80 is disposed in series with the first actuator member 21 and the fixing member 41 between the first actuator member 21 and the fixing member 41 such as a housing. The elastic member 80 is configured by a coil spring having an elastic modulus smaller than the elastic modulus of each actuator member 21, 22. One end 80 a of the elastic member 80 is connected to the end 21 b of the first actuator member 21. The other end 80b of the elastic member 80 is fixed to a fixing member 41 such as a housing.

The elastic member 80 applies a pretension to the actuator members 21 and 22 in the extension direction B of the actuator members 21 and 22 based on natural deformation. Specifically, the elastic member 80 applies an urging force in the direction indicated by the arrow A <b> 1 to the end 21 b of the first actuator member 21. Due to this urging force, each actuator member 21, 22 is given a tension in the direction indicated by arrow B. The tension applied from the elastic member 80 to the actuator members 21 and 22 is larger than the extension amount of the actuator members 21 and 22 based on natural deformation, so that the actuator members 21 and 22 can be extended in advance. It is set by.

According to the actuator device 10 of the present embodiment described above, the same or similar actions and effects as the above (1) according to the first embodiment can be obtained, and are shown in the following (5) and (6). Functions and effects can be obtained.

(5) The elastic member 80 is used as a tension applying portion that applies tension to the actuator members 21 and 22. The elastic member 80 preliminarily applies tension in the extending direction B of the actuator members 21 and 22 based on natural deformation. Thereby, compared with the structure using the tension | tensile_strength provision apparatus 50 like 1st Embodiment, tension | tensile_strength can be provided to each actuator member 21 and 22 with a simpler structure.

(6) The elastic member 80 gives each actuator member 21 and 22 a tension capable of extending each actuator member 21 and 22 larger than the extension amount of each actuator member 21 and 22 based on natural deformation. Thereby, the influence which the expansion | extension of each actuator member 21 and 22 based on a natural deformation has on the action | operation of the to-be-actuated part 30 can be suppressed more reliably.

(First modification)
Next, a first modification of the actuator device 10 according to the third embodiment will be described. Hereinafter, a description will be given focusing on differences from the actuator device 10 of the third embodiment.

As shown in FIG. 9, the first actuator member 21 and the second actuator member 22 of this modification are arranged in parallel with the axis m1 interposed therebetween. The first actuator member 21 is disposed along the axis m2. The first actuator member 21 is torsionally deformed in a rotation direction R21 centering on the axis m2 based on application of thermal energy by heating. The second actuator member 22 is disposed along the axis m3. The second actuator member 22 is torsionally deformed in the rotation direction R22 about the axis m3 based on application of thermal energy by heating.

The one end part 21 a of the first actuator member 21 and the one end part 22 b of the second actuator member 22 are connected to the actuated part 30. The other end 21 b of the first actuator member 21 and the other end 22 a of the second actuator member 22 are fixedly attached to the fixing member 41. With such a structure, when the first actuator member 21 is torsionally deformed in the rotation direction R21 by heating, a rotational force in the rotation direction R21 is applied to the operated part 30. Due to the rotational force in the rotational direction R21, the actuated portion 30 is rotationally displaced in the first direction R11. Further, when the second actuator member 22 is torsionally deformed in the rotation direction R22 by heating, a rotational force in the rotation direction R22 is applied to the operated part 30. The operated portion 30 is rotationally displaced in the second direction R12 by the rotational force in the rotational direction R22.

The one end portion 80a of the elastic member 80 is connected to the side surface of the operated portion 30 opposite to the side surface to which the actuator members 21 and 22 are connected. The other end portion 80 b of the elastic member 80 is fixedly attached to the fixing member 40. The elastic member 80 applies a pretension to the actuator members 21 and 22 in the extension direction B of the actuator members 21 and 22 based on natural deformation. Specifically, the elastic member 80 applies an urging force in the direction indicated by the arrow A2 to the operated part 30. Due to this urging force, the actuator members 21 and 22 are applied with tension in the direction indicated by the arrow A2.

Even with the actuator device 10 having such a configuration, the same or similar actions and effects as those of the third embodiment can be obtained.

(Second modification)
Next, a second modification of the actuator device 10 according to the third embodiment will be described. Hereinafter, a description will be given focusing on differences from the actuator device 10 of the third embodiment.

As shown in FIG. 10, in the actuator device 10 of this modification, an elastic member 80 is disposed between the first actuator member 21 and the actuated portion 30. Even with such a configuration, the same and similar operations and effects as those of the third embodiment can be obtained.

<Fourth embodiment>
Next, a fourth embodiment of the actuator device 10 will be described. Hereinafter, a description will be given focusing on differences from the actuator device 10 of the third embodiment. In the present embodiment, the axis m1 is also referred to as “the central axis m1 of the first actuator member 21” and “the central axis m1 of the second actuator member 22”.

As shown in FIG. 11, the actuator device 10 according to the present embodiment includes a first tension applying mechanism 100 provided at an end 21 b of the first actuator member 21 and a second actuator member 22 instead of the elastic member 80. And a second tension applying mechanism 110 provided at the end 22b.

The first tension applying mechanism 100 applies a tension in the direction indicated by the arrow A1 to the first actuator member 21. Specifically, the first tension applying mechanism 100 includes a fixing portion 101, a housing 102, and a coil spring 103.

The fixing portion 101 is fixed to the end portion 21b of the first actuator member 21 by adhesion or the like. The fixed portion 101 is formed in a flange shape so as to protrude from the outer peripheral surface of the end portion 21b of the first actuator member 21 in the radial direction centering on the axis m1.

The housing 102 is formed in a bottomed cylindrical shape around the axis m1. Inside the housing 102, a fixed portion 101 is slidably accommodated. The housing 102 has a bottom portion 102 a at an end facing the operated portion 30. A through hole 102b having the axis m1 as a central axis is formed in the bottom 102a. An end portion 21b of the first actuator member 21 extends into the housing 102 through the through hole 102b and is fixed to the fixing portion 101. The end of the housing 102 opposite to the end where the bottom 102 a is provided is fixed to the fixing member 41. The inner diameter of the through hole 102 b is larger than the outer diameter of the first actuator member 21. Therefore, when the first actuator member 21 expands and contracts in the direction B, it is difficult for a frictional force to be generated between the first actuator member 21 and the housing 102.

The coil spring 103 is disposed so as to include the end 21b of the first actuator member 21 therein. The coil spring 103 is provided on the outer periphery of the end 21 b of the first actuator member 21 so that the center axis thereof coincides with the center axis m <b> 1 of the first actuator member 21. The coil spring 103 is arranged in a compressed state between the fixed portion 101 and the bottom portion 102a of the housing 102, thereby applying an elastic force in the direction indicated by the arrow A1 to the fixed portion 101. Thereby, the tension | tensile_strength of the direction shown by arrow A 1 is provided to the 1st actuator member 21. FIG.

One end of the coil spring 103 is inserted into a concave groove 101 a formed in the fixed portion 101. The other end of the coil spring 103 is inserted into a concave groove 102 c formed in the housing 102. By inserting both end portions of the coil spring 103 into the grooves 101a and 102c, the outer peripheral portion of the coil spring 103 is positioned. Accordingly, a gap is provided between the inner peripheral portion of the coil spring 103 and the outer peripheral portion of the first actuator member 21, and a gap is provided between the outer peripheral portion of the coil spring 103 and the inner peripheral portion of the housing 102. ing. Due to these gaps, when the coil spring 103 is elastically deformed, a friction force is hardly generated between the coil spring 103 and the first actuator member 21, and a friction force is generated between the coil spring 103 and the housing 102. It is hard to occur.

The second tension applying mechanism 110 applies the tension in the direction indicated by the arrow A2 opposite to the direction indicated by the arrow A1 to the second actuator member 22. Similar to the first tension applying mechanism 100, the second tension applying mechanism 110 includes a fixing portion 111, a housing 112, and a coil spring 113. In addition, since the structure and function of these elements are the same as the structure and function of each element of the 1st tension | tensile_strength provision mechanism 100, those detailed description is omitted.

According to the actuator device 10 of the present embodiment described above, the same or similar operations and effects as the above (1) according to the first embodiment can be obtained, and the following (7) to (9) are shown. Functions and effects can be obtained.

(7) The coil springs 103 and 113 are used as tension applying portions that apply tension to the actuator members 21 and 22. The coil springs 103 and 113 preliminarily apply tension in the extending direction B of the actuator members 21 and 22 based on natural deformation. Thereby, compared with the structure using the tension | tensile_strength provision apparatus 50 like 1st Embodiment, tension | tensile_strength can be provided to each actuator member 21 and 22 with a simpler structure.

(8) The coil spring 103 is provided on the outer periphery of the first actuator member 21. The coil spring 113 is provided on the outer periphery of the second actuator member 22. Thereby, compared with the case where the tension | tensile_strength providing apparatus 50 like 1st Embodiment is provided in each edge part of the actuator members 21 and 22, it can avoid the enlargement of the actuator apparatus 10 in the direction along the axis line m1. it can.

(9) The coil springs 103 and 113 contain the actuator members 21 and 22, respectively. Thereby, the enlargement of the actuator device 10 in the radial direction around the axis m1 can be avoided.

(Modification)
Next, a modification of the actuator device 10 according to the fourth embodiment will be described. Hereinafter, the difference from the actuator device 10 of the fourth embodiment will be mainly described.

As shown in FIG. 12, the first tension applying mechanism 100 of this modification has two coil springs 104a and 104b. The coil springs 104a and 104b are provided on the outer periphery of the end portion 21b of the first actuator member 21 so that their center axes m10 and m11 are shifted from the center axis m1 of the actuator member 21. More specifically, as shown in FIG. 13, the central axes m10 and m11 of the two coil springs 104a and 104b are equiangularly spaced at the same circumference C around the central axis m1 of the first actuator member 21. It is arranged at the position. Thereby, tension in the direction indicated by the arrow A <b> 1 can be applied to the first actuator member 21 without generating a moment in the first actuator member 21.

As shown in FIG. 12, one end of the coil spring 104 a is inserted into a protruding portion 101 b formed on the fixed portion 101. The other end of the coil spring 104 a is inserted into a protruding portion 102 d formed on the housing 102. By inserting both end portions of the coil spring 104a into the protruding portions 101b and 102d, the inner peripheral portion of the coil spring 104a is positioned. Similarly, the inner peripheral portion of the coil spring 104 b is also positioned by the protruding portion 101 c formed on the fixed portion 101 and the protruding portion 102 e formed on the housing 102. Accordingly, a gap is provided between the inner peripheral portion of each of the coil springs 104 a and 104 b and the outer peripheral portion of the first actuator member 21, and the outer peripheral portion of each of the coil springs 104 a and 104 b and the inner peripheral portion of the housing 102. There is a gap between them. Due to these gaps, when the coil springs 104a and 104b are elastically deformed, frictional force is hardly generated between the coil springs 104a and 104b and the first actuator member 21, and the coil springs 104a and 104b and the housing 102 are Friction is less likely to occur during

As shown in FIG. 12, the second tension applying mechanism 110 also has two coil springs 114a and 114b, similar to the first tension applying mechanism 100. Since the structure of these coil springs 114a and 114b is the same as that of the coil springs 104a and 104b of the first tension applying mechanism 100, their detailed description is omitted.

According to such an actuator device 10, the actions and effects shown in the above (7) and (8) by the actuator device 10 of the fourth embodiment can be obtained. Further, as compared with the actuator device 10 of the fourth embodiment, the tension applied to the actuator members 21 and 22 can be increased by the increase in the number of coil springs.

Note that the number of coil springs arranged on the outer periphery of the actuator members 21 and 22 is not limited to two and can be changed as appropriate. For example, when three coil springs are provided on the outer periphery of the first actuator member 21, the center axes m10 to m12 of the three coil springs are the center axes of the first actuator member 21, as shown in FIG. It arrange | positions in the position which becomes equiangular spacing in the same periphery C centering on m1.

<Other embodiments>
In addition, each embodiment can also be implemented with the following forms.
-The tension | tensile_strength provision apparatus 50 of 1st Embodiment may adjust the magnitude | size of the tension | tensile_strength provided to the actuator members 21 and 22 so that the tension | tensile_strength provided to the actuator members 21 and 22 may become a fixed magnitude | size. For example, when the actuator members 21 and 22 have the characteristic of expanding in the direction B of FIG. Is displaced in the direction A1, and the tension applied to the actuator members 21 and 22 is adjusted to a constant magnitude. On the other hand, when the actuator members 21 and 22 have a characteristic of contracting in the direction B by the application of heat, the tension applying device 50 moves the movable part 51 in the direction when the actuator members 21 and 22 are thermally contracted. By displacing in the direction opposite to A1, the tension applied to the actuator members 21, 22 is adjusted to a constant magnitude. Thereby, even when the actuator members 21 and 22 have the characteristic of thermal expansion or contraction, the tension change of the actuator members 21 and 22 can be corrected. A similar configuration can also be realized by the actuator device 10 of the second embodiment.

The elastic member 80 of the third embodiment is not limited to a coil spring, and a mainspring spring, a leaf spring, and other appropriate elastic members can be used. Further, the number of elastic members 80 is not limited to one, and may be plural.

In the actuator device 10 according to the third embodiment, even if the actuator members 21 and 22 have a characteristic of contracting in the direction B due to thermal contraction, the elastic member 80 is provided at the end 21b of the actuator member 21. If connected, the elastic member 80 is deformed in the direction B, so that the stress applied to the actuator members 21 and 22 can be relaxed. Therefore, an effect of improving the durability of the actuator members 21 and 22 can be obtained.

In the actuator device 10 of the fourth embodiment, the number and arrangement of coil springs may be changed as appropriate. For example, in the actuator device 10 of the modification of the fourth embodiment, only one of the coil springs 104a and 104b is provided on the outer periphery of the first actuator member 21, and the coil springs 114a and 114b are provided on the outer periphery of the second actuator member 22. Only one of these may be provided. Further, for example, as shown in FIG. 15, the configuration of the coil spring of the actuator device 10 shown in FIG. 11 may be combined with the configuration of the coil spring of the actuator device 10 shown in FIG.

In the actuator device 10 according to the fourth embodiment, only one of the first tension applying mechanism 100 and the second tension applying mechanism 110 may be provided.

In the actuator device 10 of the fourth embodiment, an appropriate elastic member such as a mesh spring may be used instead of the coil springs 103, 104a, 104b, 113, 114a, 114b.

· The coil spring 103 of the fourth embodiment shown in Fig. 11 may be positioned at the inner peripheral portion thereof by the fixing portion 101 and the housing 102. The same applies to the coil spring 113. Further, the coil springs 104a and 104b of the modification of the fourth embodiment shown in FIG. 12 may have their outer peripheral portions positioned by the fixing portion 101 and the housing 102. The same applies to the coil springs 114a and 114b.

The method of heating each actuator member 21 to 23 is not limited to a method of heating by supplying an electric current to the metal plating formed on the surface, and an appropriate method can be adopted. For example, a coil may be wound around the outer peripheral surfaces of the actuator members 21 to 23, and the actuator members 21 to 23 may be heated by energizing the coils. Alternatively, each actuator member 21 to 23 may be heated using a heater or the like.

The actuator members 21 and 22 are not limited to those that are torsionally deformed based on energy application, but may be those that are linearly displaced in the longitudinal direction based on energy application. For example, as each of the actuator members 21 and 22, an actuator member that expands and deforms in a direction parallel to the axis m1 based on heating and contracts and deforms in a direction parallel to the axis m1 based on cooling can be used.

The material of each of the actuator members 21 to 23 is not limited to polymer fiber, but is an appropriate material that deforms in response to external energy input by electrical, optical, chemical, thermal, absorption, or other means. Can be used. Examples of such materials include shape memory alloys, dielectric elastomers, magnetic gels, and conductive polymers.

As for the material of the correcting actuator member 23 according to the modification of the first embodiment, an appropriate material that deforms in response to external energy input can be used. Note that the material of the correcting actuator member 23 may be the same as or different from the material of the first actuator member 21. When the material of the correction actuator member 23 and the material of the first actuator member 21 are the same, the correction actuator member 23 and the first actuator member 21 may be integrally formed.

The means and / or function provided by the control unit 70 can be provided by software stored in a substantial storage device and a computer that executes the software, only software, only hardware, or a combination thereof. For example, when the control unit 70 is provided by an electronic circuit that is hardware, it can be provided by a digital circuit including a large number of logic circuits or an analog circuit.

・ This disclosure is not limited to the above specific examples. Any of the above specific examples that are appropriately modified by those skilled in the art are also included in the scope of the present disclosure as long as they have the features of the present disclosure. Each element included in each of the specific examples described above, and the arrangement, conditions, shape, and the like thereof are not limited to those illustrated, and can be appropriately changed. Each element included in each of the specific examples described above can be appropriately combined as long as no technical contradiction occurs.

Claims (12)

1. An actuator member (21, 22) that deforms in response to external energy application;
   An actuated portion (30) coupled to the actuator member;
   A drive section (61, 62) for displacing the actuated section in the deformation direction of the actuator member by applying energy to the actuator member;
   Tension applying portions (23, 50, 63, 80, 103, 104a, 104b, 113) that apply to the actuator member a tension that can correct a change in tension based on at least one of expansion and contraction of the actuator member due to natural deformation. 114a, 114b), and an actuator device.
2. The tension applying portion (23, 50, 63)
   The tension applied to the actuator member can be electrically controlled;
   While applying tension to the actuator member at the start of operation of the actuated part or immediately before,
   The actuator device according to claim 1, wherein the tension applied to the actuator member is released at the time of stopping the operation of the operated part or immediately after that.
3. The tension applying part (50)
   The actuator device according to claim 2, wherein the actuator device is an electromagnetic actuator device or a motor device.
4. The tension applying unit is
   A correction actuator member (23) for applying a tension to the actuator member that can correct a change in tension due to at least one of expansion and contraction of the actuator member due to natural deformation in response to external energy application;
   The actuator device according to claim 2, further comprising: a correction driving unit (63) that applies energy to the correction actuator member.
5. The tension applying unit is
   2. The actuator device according to claim 1, wherein the actuator device is an elastic member (80) that preliminarily applies tension to the actuator member in an extension direction of the actuator member based on natural deformation.
6. The elastic member is
   The actuator device according to claim 5, wherein a tension capable of extending the actuator member larger than an extension amount of the actuator member based on natural deformation is applied to the actuator member.
7. The elastic member is
   The actuator device according to claim 5, wherein the actuator device is any one of a coil spring, a mainspring spring, and a leaf spring.
8. The tension applying portions (103, 104a, 104b, 113, 114a, 114b)
   The actuator device according to claim 1, wherein the actuator device is provided on an outer periphery of the actuator member.
9. The tension applying portions (104a, 104b, 114a, 114b)
   The actuator device according to claim 8, wherein a plurality of actuator devices are arranged on the same circumference centering on a central axis of the actuator member.
10. The tension applying portions (103, 113)
    The actuator device according to claim 8 or 9, comprising the actuator member.
11. The tension applying unit is
    The actuator device according to any one of claims 8 to 10, comprising a coil spring.
12. The actuator member is
    The actuator device according to any one of claims 1 to 11, comprising a polymer fiber.

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