JP2011127557A - Actuator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide technique which allows the generation of large driving force while inhibiting a load on an actuator. <P>SOLUTION: In the actuator 100, a load mechanism 104 is connected with a connection 107 of an operation part 103 and gives a load for displacing the operation part 103 to generate a driving force F2 at an action point 106. A bias mechanism 105 gives a biasing force in a direction for holding the operation part 103 at a predetermined position against the load by the load mechanism 104. The operation part 103 includes a variable elastic mechanism 108 which elastically deforms as the load given by the load mechanism 104 becomes larger and autonomously varies a moment arm l1, which is the length of a perpendicular line dropped from a fulcrum 102 to the vector of force F1 acting on the connection 107, in a direction for increasing the driving force F2. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an actuator, and more particularly to an actuator that utilizes the expansion and contraction force of a shape memory alloy.

  2. Description of the Related Art Conventionally, an actuator that drives an object using the stretching force of a shape memory alloy is known. For example, an actuator using a wire made of a shape memory alloy (hereinafter also referred to as “shape memory alloy wire”) may be used for detaching the fastener of the unlocking mechanism (see, for example, Patent Document 1). . Such a shape memory alloy wire stretches and deforms when pulled in the longitudinal direction at room temperature, and contracts to its original length by a shape recovery force when heated. Utilizing this property, the shape memory alloy wire is stretched by the biasing force of the spring when not energized, and the fastener is urged to the locked position to bring it into the locked state, and when unlocked, the shape memory alloy wire is energized and heated. By doing so, the fastener is retracted against the urging force of the spring, and the unlocked state is obtained. An actuator using the shape recovery force of such a shape memory alloy has excellent characteristics such as downsizing, light weight, and quietness of the device.

JP 2000-352239 A

  By the way, the force acting on such an actuator does not always take a large value during the operation. For example, in the above-described unlocking mechanism, the maximum force is required when the frictional force applied to the fastener shifts from static friction to dynamic friction, that is, the moment when the fastener starts to move. In other words, if the maximum force can be exerted when necessary, it can function as an actuator in the entire operation process. Therefore, if the actuator can be configured compactly while ensuring the maximum force, it is convenient in terms of the device configuration.

  On the other hand, some of these shape memory alloy wires have a relatively large amount of expansion / contraction, but currently they are 5% or less in terms of tensile strain, and other cylinder mechanisms such as a reciprocating motion are used. The amount of displacement is small compared to the actuator. For this reason, in order to ensure a practical amount of movement of a driving target using an actuator using such a shape memory alloy wire, some kind of strain amplification mechanism such as a lever or a pulley is often required. However, as the mechanism becomes more complicated, it is assumed that an unexpected load acts on the shape memory alloy wire. For example, it is assumed that an external force is applied for some reason during the shape recovery of the shape memory alloy wire and the operation of the amplification mechanism is restricted. In such a case, if the shape recovery of the shape memory alloy wire is continued as it is, the reaction force from the amplification mechanism becomes an excessive tensile stress, which may damage or deteriorate the shape memory alloy wire. In order to cope with this, it is possible to detect the tensile stress of the shape memory alloy wire and cut off the power supply when the set value is exceeded, but this will stop the operation of the actuator itself. Must not. Also, simply avoiding an unexpected load from acting on the actuator results in a versatile actuator that functions only for the assumed load.

  The present invention has been made in view of such problems, and one of its purposes is to reduce the load on an actuator when an unexpected load is applied when a predetermined operation amount is realized by the actuator. An object of the present invention is to provide a technique for temporarily generating a large driving force corresponding to the load while overcoming the load and overcoming the load to realize a predetermined operation amount.

  In order to solve the above problems, an actuator according to an aspect of the present invention includes a base, a fulcrum fixed to the base, an operating part supported by the fulcrum and having an action point at a position spaced from the fulcrum, A load mechanism that is connected to a connection point that is a force point and generates a driving force at the operating point by applying a load for displacing the operating part, and holds the operating part at a predetermined position against the load by the load mechanism And a bias mechanism for applying a biasing force in the direction. The actuating part is elastically deformed as the load applied by the load mechanism increases, so that the driving force of the moment arm, which is the length of the perpendicular line drawn from the force vector acting on the connecting point from the fulcrum, is increased. Equipped with a variable elastic mechanism that changes autonomously in the direction.

  According to this aspect, the operating portion is held at a position where the moment received from the load mechanism and the moment received from the bias mechanism are balanced, but the moment arm is autonomously changed according to the magnitude of the load received from the load mechanism. . That is, when the load by the load mechanism is increased, the operating portion is elastically deformed so as to increase the moment arm. For this reason, even when a large moment is required for the operating unit to apply a large force to the drive target, the load to be supplied from the load mechanism can be small. That is, as compared with the case where the moment arm does not change, it is possible to apply a larger force to the operating portion while suppressing the load by the load mechanism. In other words, even if the same moment is generated, the reaction force applied from the operating portion to the load mechanism can be suppressed smaller than when the moment arm does not change. For this reason, for example, even if an unexpectedly large load is applied to the operating part during the operation of the actuator, the moment arm is absorbed to absorb this, and the reaction force applied to the load mechanism is suppressed to protect it. Can do. In other words, when an unexpectedly large load is applied when a predetermined operation amount is realized by the actuator, a large driving force corresponding to the load is temporarily generated while suppressing the load on the actuator. A predetermined amount of operation can be realized by overcoming the load.

  According to the present invention, when an unexpected load is applied when a predetermined operation amount is realized by the actuator, a large driving force corresponding to the load is temporarily generated while suppressing the load on the actuator. In addition, the predetermined amount of operation can be realized by overcoming the load.

It is the schematic showing the structure and operating principle of the actuator which concern on embodiment. It is the schematic showing the structure of the actuator which concerns on 1st Example. It is explanatory drawing showing operation | movement of an actuator. It is a figure which shows the modification of 1st Example. It is a figure which shows the other modification of 1st Example. It is a figure showing the structure of the actuator which concerns on 2nd Example. It is explanatory drawing showing operation | movement of an actuator. It is a figure showing the structure of the actuator which concerns on the comparative example of 2nd Example. It is a figure showing schematic structure of the lock device to which the actuator concerning a 3rd example was applied. It is a figure showing the structure of the actuator which concerns on 4th Example. It is the schematic showing the electric constitution of the drive control apparatus of an actuator. It is explanatory drawing showing operation | movement of an actuator.

FIG. 1 is a schematic diagram illustrating a configuration and an operation principle of an actuator according to the embodiment. FIGS. 4A and 4B show the operation process of the actuator.
As shown in FIG. 1A, an actuator 100 according to an embodiment includes a base 101, a fulcrum 102 fixed to the base 101, an operating part 103 supported by the fulcrum 102, and a load applied to the operating part 103. And a bias mechanism 105 that biases the operating unit 103 to hold it in a predetermined position. The operating part 103 has an action point 106 at a position separated from the fulcrum 102. The load mechanism 104 is connected to a connection point 107 that is a power point of the operating unit 103, and generates a driving force F2 at the operating point 106 by applying a force F1 for displacing the operating unit 103. The bias mechanism 105 applies a biasing force in a direction to hold the operating unit 103 at a predetermined position against the load by the load mechanism 104. The operating portion 103 is elastically deformed as the load applied by the load mechanism 104 increases, so that the moment arm 11 that is the length of the perpendicular line drawn from the vector of the force F1 acting on the connecting point 107 from the fulcrum 102 is applied. And a variable elastic mechanism that autonomously changes the driving force F2 in the increasing direction.

  Specifically, the fulcrum 102 is provided as a rotating shaft fixed to the base 101, and the operating portion 103 is rotatably supported by the rotating shaft. The load mechanism 104 applies a load that rotates the operation unit 103 around the rotation axis. The variable elastic mechanism elastically deforms in accordance with the magnitude of the load applied by the load mechanism 104, thereby converting the moment arm, which is the length of a perpendicular line from the force vector acting on the connection point from the rotation axis, to the load mechanism. The distance between the connecting point 107 of 104 and the rotation axis is autonomously changed.

  In the illustrated example, the operating unit 103 includes an arm 150 extending in one direction from the fulcrum 102 and a guide rod 152 extending from the fulcrum 102 in the opposite direction to the arm 150. A cylindrical connecting portion 154 is slidably inserted in the guide rod 152. A stopper 156 is provided at the end of the guide rod 152 opposite to the fulcrum 102, and an elastic member 158 is provided so as to be interposed between the connecting portion 154 and the stopper 156. The load mechanism 104 is connected to a connection point 107 provided in the connection part 154. In this embodiment, the load mechanism 104 is made of a shape memory alloy that expands and contracts according to the energized state, and the bias mechanism 105 and the elastic member 158 are made of a coil spring. The connecting portion 154 and the elastic member 158 function as a variable elastic mechanism that changes the moment arm 11 according to the magnitude of the load applied from the load mechanism 104.

  Until the load applied from the load mechanism 104 reaches a predetermined value, the actuator 100 operates in the clockwise direction of the drawing with the fulcrum 102 as the center by pulling the connecting portion 154 by contraction of the load mechanism 104. At this time, as shown in FIG. 5A, the moment arm 11 between the fulcrum 102 and the connecting point 107 is generally held against the force F1. On the other hand, the moment arm l2 between the fulcrum 102 and the action point 106 is larger than the moment arm l1, and at this time, a driving force F2 is generated at the action point 106.

  In this state, for example, when an unexpectedly large load is applied to the operating unit 103 during the operation of the actuator 100, the moment arm between the fulcrum 102 and the connection point 107 is increased to absorb this. For example, when the action point 106 is restrained and the rotation of the arm 150 is prevented as shown in FIG. 5B, the action point 106 is generated by an action to increase the load of the load mechanism 104. Even if the driving force increases unexpectedly, the moment arm between the fulcrum 102 and the connecting point 107 increases to match the increase. This figure shows an example in which the moment arm between the fulcrum 102 and the connecting point 107 is increased to l1 'because the driving force has increased from F2 to F2'. At this time, the moment arm between the fulcrum 102 and the connecting point 107 changes so that the moment caused by the force F1 and the moment arm l1 'balances the moment caused by the driving force F2' and the moment arm l2. That is, even if an unexpected load is applied, an increase in the force F1 applied from the load mechanism 104 can be suppressed. In other words, according to the actuator 100, a large driving force can be taken out while suppressing an increase in the load applied to the operating portion 103 by the load mechanism 104.

  That is, with the above configuration, when an unexpectedly large load is applied when a predetermined operation amount is realized by the actuator, the load on the actuator is suppressed and the load is temporarily overcome. A large driving force corresponding to the load can be generated. That is, if the generated force of the load mechanism is small, there is an advantage that the size of the actuator is small, which can contribute to miniaturization, weight reduction, and energy saving. As a demerit against this, when an unexpected load is applied, there is a possibility that an excessive load is applied to the small load mechanism and it may be broken or not function normally, and it is necessary to avoid this. However, simply avoiding the application of a large load results in a less versatile actuator that functions only with an assumed load. However, according to the present embodiment, in the range of force that can be generated by the actuator, when a load that was not assumed is applied, a larger generated force can be temporarily extracted, and the unexpected load is removed, and the actuator is removed. A predetermined operation amount can be realized.

  More specifically, the actuating part is a main body that is rotatably supported by the rotation shaft, a rotation fulcrum provided at a position separated from the rotation axis of the main body, and the rotation fulcrum extends in the vicinity of the rotation shaft. And an elastic part that generates an urging force in a direction that maintains the positional relationship between the main body and the arm part. A connecting point with the load mechanism is provided in the arm portion, and the variable elastic mechanism is armed against the elastic force of the elastic portion so that the moment arm is changed according to the magnitude of the load applied by the load mechanism. The part may be displaced around the rotation fulcrum.

  The “rotation” referred to here may be one in which the arm portion rotates around the rotation fulcrum, or the arm portion may be deformed around the rotation fulcrum with respect to the main body. That is, the “rotation” referred to here may include a rotation due to deformation. With such a configuration, when the load by the load mechanism is increased, the arm portion is displaced so as to increase the moment arm. The moment arm can be changed relatively greatly by the displacement of the arm portion, which can contribute to the load relaxation to the load mechanism.

  In that case, the operation part may be one in which the main body, the rotation fulcrum, the arm part, and the elastic part are integrally formed. As long as the function of these elements is ensured, the operation part may be integrally formed of resin or the like, or may be integrally formed of a metal material. Thereby, the number of parts of an operation part can be decreased, and it also becomes possible to reduce manufacturing cost.

  The load mechanism may include a wire connected to the operating unit and a drive unit that applies a tensile load to the operating unit by displacing the wire by energization. The “driving unit” referred to here may be a simple device that turns on / off the driving force to the wire by operating a switch or the like. Or you may have a control part which determines a predetermined state inside, and may control the drive amount of a wire based on the conditions set up beforehand. By adopting a wire, the entire actuator can be made compact.

  Furthermore, the wire may be made of a shape memory alloy that expands and contracts in the longitudinal direction according to the heating state, and the drive unit may be made of an energization heating device that is electrically connected to the wire. The “shape memory alloy” may be one that undergoes a phase transition from a martensite phase to an austenite phase when heated from room temperature, and is cured in a predetermined shape. Then, when the temperature is lowered, the austenite phase may transition again to the martensite phase and soften, and may be easily deformed by an external force. When heated, it may shrink from its normal temperature due to its shape recovery force, and in that case, it may shrink and harden when heated and relax and elongate when cooled. The “shape memory alloy” may be made of a shape memory alloy having a bidirectional shape memory effect. That is, not only the shape of the austenite phase at the time of heating but also the shape of the martensite phase at room temperature may be stored. According to this aspect, the wire material reversibly expands and contracts depending on the heating state by energization / non-energization, so that the responsiveness in repeating the deformation operation is further improved. Further, since the dimensional change of the wire is stabilized with the repetition of the deformation operation, it is possible to realize a long life.

  By adopting the shape memory alloy wire in this way, for example, the wire can be displaced without providing a complicated mechanism such as a wire winding device, and a sound like when a driving device such as a motor is provided. Can be eliminated. For example, the intermediate portion of the wire may be supported by the connection point of the operating portion, and both ends may be fixed to the base. Thus, by using a double wire, it is possible to disperse the reaction force from the operating portion, and the durability as a load mechanism is improved.

  In addition, the variable elastic mechanism is configured so that the variable range of the moment arm is set so that the reaction force applied to the wire during the rotational operation process of the operating part falls within a predetermined setting range that is smaller than the tensile strength of the wire. May be. Thus, the structure of the operating part can be optimized by setting the moment arm so that the reaction force to the wire does not exceed its tensile strength in consideration of the strength of the shape memory alloy. For example, by setting the moment arm small while considering the strength of the wire, it is possible to make the actuator compact while ensuring the maximum force to be applied to the operating portion.

  An actuator according to a further embodiment includes a first rotating shaft as a rotating shaft, a first operating portion as an operating portion, and a second fixed at a position spaced apart from the first rotating shaft of the base portion. A rotating shaft, and a second operating portion that is rotatably supported by the second rotating shaft and rotates around the second rotating shaft by receiving the rotational force of the first operating portion, Due to the displacement between the actuating part and the second actuating part, the amount of displacement of the wire is amplified in a superimposed manner.

  That is, when the deformation amount of the shape memory alloy wire is limited, the displacement amount can be amplified by the cooperation of the first operating portion and the second operating portion. Accordingly, by connecting the drive target to the second operating unit, the drive target can be greatly displaced.

  Specifically, a guide portion provided in a position between the first rotation shaft and the second rotation shaft in the base portion and extending in one direction may be provided. The first actuating portion may include an intermediate arm portion that extends to the opposite side of the first rotation shaft with respect to the rotation fulcrum and has an engaging portion at a tip portion thereof. The second operating portion includes a main body extending from the second rotation shaft in the direction of the guide portion, an engaged portion that engages the engaging portion with an intermediate portion of the main body so as to be relatively displaceable, and a tip portion of the main body And a support portion that supports a predetermined drive object while being engaged and guided by the guide portion. The drive target is configured to be displaced in the extending direction of the guide portion by the rotation of the first operating portion and the second operating portion.

  According to this configuration, the first operating portion is connected to the intermediate portion of the second operating portion at the distal end portion of the intermediate arm portion, and the distal end portion of the second operating portion is further away from the first rotating shaft. Can be displaced to a different position. That is, the drive target supported by the support portion can be greatly displaced. At that time, the second operating part can move the drive object in the target direction along the guide part. As described above, the first operating portion and the second operating portion operate in cooperation, but the engaged portion of the second operating portion relatively displaces the engaging portion of the first operating portion during the operation. Since the engagement is possible, the movement of both can be kept smooth.

  Moreover, the actuator concerning further embodiment is provided as an elongate flexible member in which an action | operation part has flexibility. The load mechanism includes a first wire inserted in the longitudinal direction of the flexible member, and a drive unit that applies a tensile load to the operating unit by displacing the first wire by energization. The bias mechanism is provided as a second wire made of an elastic material inserted in the longitudinal direction of the flexible member so as to be juxtaposed with the first wire, and constitutes a fulcrum. A hole extending along both wires is provided between the first wire and the second wire of the flexible member, and the width of the hole changes when the first wire is displaced. The moment arm is configured to change autonomously.

  The “flexible member” here may be any member that has at least flexibility, but may have elasticity to restore the original shape when further deformed. Moreover, it may not have elasticity in particular. Since the second wire has elasticity, even in the latter case, the urging force for restoring the shape acts on the flexible member. The “second wire” may be made of a superelastic alloy having superelasticity. The term “superelasticity” as used herein refers to the property of returning to its original shape when a load is applied and when the load is removed. By removing, it may return to the original shape promptly. The “superelastic metal” may be a metal that changes an austenite phase to stress-induced martensite when an external force is applied and returns to the original austenite phase when the external force is removed. By configuring the first wire with a superelastic alloy in this way, the flexible member can be quickly returned to its original shape when the power supply to the second wire is stopped, and the operation as an actuator. Can increase the responsiveness. The “hole” may constitute a space. Alternatively, the hole may be filled with a material softer than the flexible member.

  According to such a configuration, when the first wire is not energized, the flexible member is held in a shape along the original shape of the second wire. On the other hand, when the first wire is contracted by energization, the flexible member is deformed so as to be pulled to the first wire together with the second wire, so that an actuator for bending or bending the flexible member is configured. be able to. When such an operation is performed, if the load due to the first wire increases, the width of the hole portion increases, and the distance between the first wire and the second wire changes. That is, the operating portion is elastically deformed so as to increase the moment arm. As a result, even when a predetermined bending moment is required to ensure the amount of operation of the operating unit, the load received from the first wire rod is suppressed by making the operating unit autonomously change the moment arm. be able to. In other words, it is possible to secure a large amount of operation of the operating unit while reducing the load on the first wire.

  Furthermore, a second hole extending along the first wire is provided on the side of the flexible member opposite to the second wire of the first wire, and the second wire is displaced when the first wire is displaced. The moment arm may be configured to be further changeable by changing the width of the hole.

  According to such a configuration, when the load due to the first wire increases, the distance between the first wire and the second wire changes so as to crush the second hole. . That is, the moment arm can be made larger, and the load on the first wire can be made smaller.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments embodying the present invention will be described below in detail with reference to the drawings. First, the configuration and operating principle of the actuator according to the embodiment will be described, and then an application example for a specific application will be described.

[First embodiment]
FIG. 2 is a schematic diagram illustrating the configuration of the actuator according to the first embodiment.
The actuator 1 of the present embodiment includes an actuator body 2 and an energizing device 3 (corresponding to an “energizing heating device”) that drives the actuator body 2. The actuator body 2 includes a base portion 10, an operating portion 12 assembled to the base portion 10, and a shape memory alloy wire 14 that applies a rotational force to the operating portion 12. The shape memory alloy wire 14 and the energization device 3 constitute a load mechanism.

  The operating unit 12 includes a rotating member 16 constituting the main body, and an arm 18 that connects the rotating member 16 and the shape memory alloy wire 14. The rotating member 16 is rotatably supported on a rotating shaft 15 provided on the base 10. The arm 18 is rotatably supported at one end of the rotating member 16. That is, the rotating member 16 has an L shape having an action part 20 extending in one direction and a transmission part 22 extending in a direction of 90 degrees with the action part 20, and at the center part thereof. Attached to the rotary shaft 15. The distal end portion of the action portion 20 serves as an action point 24 that is connected to a driving target (not shown) and applies a driving force. A rotation shaft 26 (functioning as a “rotation fulcrum”) that rotatably supports one end of the arm 18 is provided at the distal end of the transmission unit 22. In the present embodiment, the lengths of the transmission portion 22 and the arm 18 are substantially equal.

  A shape memory alloy wire 14 is attached to a connecting portion 28 projecting from the other end of the arm 18 so as to be wound. In other words, in this embodiment, the intermediate portion of one shape memory alloy wire 14 is supported by the connecting portion 28, and both ends are fixed to the base portion 10. A spring 30 is interposed between the intermediate portion in the longitudinal direction of the action portion 20 and the base portion 10. The spring 30 functions as a bias mechanism that holds the rotating member 16 at the illustrated reference position against a tensile load caused by the shape memory alloy wire 14.

  Further, a spring 32 is interposed between the longitudinal intermediate portion of the action portion 20 and the longitudinal intermediate portion of the arm 18. On the other hand, a stopper 33 is provided at the intermediate portion in the longitudinal direction of the transmission portion 22 so as to lock the arm 18 and restrict the rotation toward the transmission portion 22 side. The spring 32 functions as an elastic portion that holds the positional relationship between the rotating member 16 and the arm 18 at the reference position shown in the figure against the tensile load caused by the shape memory alloy wire 14. That is, when the shape memory alloy wire 14 is not energized, the rotating shaft 15 and the connecting portion 28 are disposed adjacent to each other by the urging force of the spring 32 as illustrated. In this embodiment, the arm 18 and the spring 32 function as a variable elastic mechanism that changes the distance between the rotating shaft 15 and the connecting portion 28 according to the magnitude of the load applied to the operating portion 12 by the shape memory alloy wire 14. To do.

  The shape memory alloy wire 14 is made of a Ni—Ti—Cu-based shape memory alloy having a so-called bidirectional shape memory effect, and is formed as a wire-like wire that contracts and hardens when heated and relaxes and expands when gradually heated. Has been. The energization device 3 includes an energization circuit for heating the shape memory alloy wire 14, and lead wires drawn from both ends of the shape memory alloy wire 14 are connected. When the switch 34 of the energization circuit is turned on, a current is supplied from the power source 36, and the shape memory alloy wire 14 connected in series thereto is energized. The energization current returns through the shape memory alloy wire 14.

Next, the operation of the actuator will be described. FIG. 3 is an explanatory diagram showing the operation of the actuator. (A) shows the operation at the time of non-energization, (B) shows the normal operation at the time of energization, and (C) and (D) show the operation when the restraining force is applied to the operating part at the time of energization.
That is, when the current is not energized, the shape memory alloy wire 14 is in a relaxed and elongated state, so that the operating portion 12 balances the tension by the shape memory alloy wire 14 and the biasing force by the spring 30 as shown in FIG. Held at the reference position. At this time, the moment arm between the rotating shaft 15 and the connecting portion 28 is l1, and the moment arm between the rotating shaft 15 and the action point 24 is l2.

  When energization is performed from this state, the heated shape memory alloy wire 14 is tensioned and contracted, so that the tension of the shape memory alloy wire 14 is increased. As a result, the rotational moment in one direction due to the load applied to the connecting portion 28 is increased, and as shown in FIG. 5B, the operating portion 12 as a whole is centered on the rotating shaft 15 in one direction (clockwise). Rotate. As a result, the action portion 20 tilts against the urging force of the spring 30 as shown in the figure, and the drive target connected to the action point 24 is driven in one direction. On the other hand, when the energization is cut off from this state, the shape memory alloy wire 14 again relaxes and extends, so that the operating portion 12 is rotated in the opposite direction (counterclockwise) by the urging force of the spring 30, and FIG. To the reference position shown in FIG. At this time, the moment arm between the rotary shaft 15 and the connecting portion 28 is l1, and the moment arm between the rotary shaft 15 and the action point 24 is l2, which is not changed. Moreover, the action | operation part 12 can generate the drive force F2 with respect to the drive object which is not shown in figure.

  Here, it is assumed that an external force is generated that gives an excessive reaction force to the shape memory alloy wire 14 during energization. For example, as shown in FIG. 5C, when the action point 24 of the operating portion 12 is constrained and the rotation of the rotating member 16 is prevented, if the energization is continued as it is, the shape memory alloy wire 14 The contractive force of the motor continues to increase, and the driving force changes from F2 to F2 ′ so as to balance it. However, when the contraction force of the shape memory alloy wire 14 exceeds the urging force of the spring 32, the arm 18 rotates about the rotation shaft 26 as shown in FIG. As a result, the length of the perpendicular (moment arm) that changes from the rotational axis 15 (fulcrum) to the force vector acting on the connecting portion 28 (connecting point) changes. That is, even if the rotational moment increases, the moment arm increases from l1 to l1 ', so that an increase in the reaction force from the operating portion 12 acting on the shape memory alloy wire 14 can be suppressed. That is, even if the load on the shape memory alloy wire 14 increases due to such an unexpected external force, the operating portion 12 is elastically deformed at the portion of the arm 18 to lengthen the moment arm, and as a result, the load The increase can be suppressed. Thereby, the breakage of the shape memory alloy wire 14 and the deterioration of the material can be prevented.

  In addition, similar effects can be obtained even during normal energization where no such restraining force is applied. That is, it is assumed that a large rotational moment is required for the operating unit 12 in order to extract a larger displacement amount of the drive target during energization shown in FIG. Even in such a case, when the contraction force of the shape memory alloy wire 14 exceeds the urging force of the spring 32 in accordance with the increase of the rotational moment, the action portion 20 is rotated and the arm 18 is also rotated. become. That is, even if the rotational moment increases, the moment arm becomes large, and thus the reaction force on the shape memory alloy wire 14 is suppressed from increasing. As a result, it is possible to secure a larger displacement amount of the operating portion 12 and, consequently, an operation amount of the drive target, without substantially damaging the shape memory alloy wire 14.

[Modification]
FIG. 4 is a diagram showing a modification of the first embodiment. FIG. 4A shows a first modification, and FIG. 4B shows a second modification.
In the said 1st Example, although the intermediate part of the shape memory alloy wire 14 was wound around the connection part 28, and the both ends were fixed to the base 10, the example which uses a double wire was shown, but it is different from this. You may employ | adopt the structure and arrangement | positioning of a shape memory alloy wire.

  That is, when the strength of the shape memory alloy wire is not so required by setting the change range of the moment arm, the base portion 10 and the connecting portion 28 are connected by one shape memory alloy wire 114 as in the first modification. It is good also as a simple structure to connect. Conversely, when a shape memory alloy wire having a higher strength is required, a coiled shape memory alloy wire 124 is used instead of a wire shape memory alloy wire as in the second modification. Also good.

FIG. 5 is a diagram showing another modification of the first embodiment. FIG. 5A shows a third modification, and FIG. 5B shows a fourth modification.
In the first embodiment, the rotating member 16 is provided with the rotatable arm 18 and the spring 32 that biases the arm 18 to the reference position, and the operating portion 12 is elastically deformed in response to the load from the shape memory alloy wire 14. Although an example is shown, a different configuration and arrangement may be adopted.

  For example, as in the third modified example, the rotating portion 116 and the arm portion 118 of the operating portion 112 may be integrally formed by resin injection molding or the like to have elasticity. In the example shown in the drawing, the rotating part 116 is constituted by an action part 120 and a transmission part 122, and an arm part 118 is extended so that the tip of the transmission part 122 is folded back. A virtual pivot fulcrum 126 is formed at the folding position. When the load on the shape memory alloy wire 14 is increased, the rotating portion 116 is elastically deformed so that the distance between the transmitting portion 122 and the arm portion 118 is increased. That is, the connecting portion of the transmission portion 122 and the arm portion 118 functions like the spring 32 of the first embodiment. At this time, the moment arm l which is the length of the perpendicular line drawn from the force vector acting on the connecting portion 28 (connecting point) from the rotating shaft 15 becomes large, and the same effect as in the first embodiment can be obtained.

  Alternatively, as in the fourth modified example, in the rotating portion 136 of the operating portion 115, the operating portion 130 is configured to extend on the opposite side of the rotating shaft 15 with respect to the rotating fulcrum 126, and acts on the tip portion thereof. A point 24 may be provided. Note that the spring 30 as a bias mechanism is connected to the distal end portion of the support portion 132 extending in a direction of 90 degrees with the transmission portion 122. With such a configuration, the distance between the action point 24 and the rotary shaft 15 is increased, and the displacement of the action point 24 and thus the operation amount of the drive target can be increased.

[Second Embodiment]
FIG. 6 is a diagram illustrating the configuration of the actuator according to the second embodiment. For the sake of convenience, this figure shows the actuator mechanism viewed from the bottom side.
The actuator 201 according to the present embodiment realizes a slide mechanism that drives a predetermined drive target in one direction using a part of the actuator shown in FIG. The actuator 201 has a double lever structure for greatly amplifying the displacement amount of the operating portion.

  That is, the actuator 201 includes a first operating unit 202, a second operating unit 204, and a mounting table 206. Is reciprocated in one direction. A housing 210 serving as a base is provided with a guide slit 208 extending in one direction. The rotating shaft 15 of the first operating unit 202 is provided on one side of the guide slit 208, and the rotating shaft 215 of the second operating unit 204 is provided on the other side. The mounting table 206 is for mounting a predetermined drive target and is guided in one direction along the guide slit 208. In other words, a rectangular guide portion 211 is projected from the lower surface of the mounting table 206, and the guide portion 211 is slidably assembled along the guide slit 208. An engaging portion 212 projects from the center of the lower surface of the guide portion 211.

  As the first operation unit 202, the operation unit 115 illustrated in FIG. 5B is applied. The first actuating part 202 has an action part 130 (functioning as an “intermediate arm part”) extending on the opposite side of the rotation shaft 15 with respect to the rotation fulcrum 126. An engaging part 224 is projected from an action point located at the tip of the action part 130. The second operating part 204 has a main body 216 that extends toward the guide slit 208. A connecting portion 217 to which the first actuating portion 202 is connected is provided at an intermediate portion in the longitudinal direction of the main body 216. The connecting portion 217 is provided with a guide slit 218 having a predetermined length along the longitudinal direction of the main body 216, and the engaging portion 224 of the first operating portion 202 is engaged so as to be relatively displaceable. In addition, a connecting portion 220 connected to the mounting table 206 is provided at the distal end portion of the main body 216. The connecting portion 220 is provided with a guide slit 222 having a predetermined length along the longitudinal direction of the main body 216, and the engaging portion 212 of the mounting table 206 is engaged so as to be relatively displaceable.

Next, the operation of the actuator will be described. FIG. 7 is an explanatory diagram illustrating the operation of the actuator. (A) shows the operation when not energized, and (B) shows the normal operation when energized.
Since the shape memory alloy wire 14 is in a relaxed and elongated state when not energized, the first actuating portion 202 and the second actuating portion 204 are subjected to tension and spring 30 by the shape memory alloy wire 14 as shown in FIG. It is held at a reference position in which the urging force by is balanced. At this time, as illustrated, the first operating unit 202 and the second operating unit 204 are arranged on a straight line connecting the rotating shaft 15 and the rotating shaft 215.

  When energization is performed from this state, the heated shape memory alloy wire 14 is tensioned and contracted, and a unidirectional rotational moment due to a load applied to the connecting portion 28 is increased. As a result, as shown in FIG. 4B, the first operating portion 202 as a whole rotates about the rotary shaft 15 in the clockwise direction in the figure. As a result, the action portion 130 rotates as shown in the figure, and moment force is applied to the second operating portion 204 while sliding the engaging portion 224 along the guide slit 218. As a result, the second actuating portion 204 rotates about the rotation shaft 215 counterclockwise in the figure. As a result, the second operating unit 204 drives the mounting table 206 in one direction while sliding the engaging unit 212 along the guide slit 222. As a result, the drive target placed on the placement table 206 is driven in one direction. On the other hand, when the energization is interrupted from this state, the shape memory alloy wire 14 again relaxes and extends, so that the first operating unit 202 and the second operating unit 204 rotate in the opposite direction, and the mounting table 206 is the same. The reference position shown in FIG.

  Here, if a force that gives an excessive reaction force to the shape memory alloy wire 14 is generated during energization, the arm portion 118 is bent so as to rotate about the rotation fulcrum 126, and the rotating shaft 15. To the connecting portion 28 (connecting point) is elastically deformed so that the length of the perpendicular line (that is, the moment arm l) is reduced. For this reason, an increase in the reaction force acting on the shape memory alloy wire 14 can be suppressed. Thereby, the breakage of the shape memory alloy wire 14 and the deterioration of the material can be prevented. In the present embodiment, since a double lever structure is adopted, a large displacement X of the mounting table 206 can be generated with respect to a slight displacement x of the shape memory alloy wire 14, and a sufficient amount of movement of the drive target can be achieved. It can be secured.

FIG. 8 is a diagram illustrating a configuration of an actuator according to a comparative example of the second embodiment.
The actuator 251 of this comparative example is not provided with a structure for changing the distance between the rotating shaft 15 and the connecting portion 28 as in the second embodiment. That is, since the rotating mechanism 236 of the first operating unit 252 is not provided with an elastic mechanism that changes the moment arm 10, the load of the shape memory alloy wire 14 increases as the rotational moment of the first operating unit 252 increases. It may become excessive and cause breakage. In this respect, since the moment arm can be changed in the second embodiment, it can be said that the above-described merit is obtained.

[Third embodiment]
FIG. 9 is a diagram illustrating a schematic configuration of a lock device to which the actuator according to the third embodiment is applied. (A) shows the state when the unlocking operation is started from the locked state of the locking device, and (B) shows the unlocked state.
The actuator 301 of this embodiment is mainly used as an unlocking mechanism of the lock device 300. The lock device 300 includes a lock / unlock mechanism inside a lock body 304 attached to a door. The lock device 300 includes a lock mechanism 306 for performing a locking / unlocking operation inside the housing 310 of the lock body 304. The lock mechanism 306 includes a lock member 312 and a fixing piece 314.

  The lock member 312 has a columnar main body, and a concave fitting portion 313 is provided on the central side wall thereof. One end of the lock member 312 is inserted into a fitting hole 308 provided in the lock body 304. A spring 318 that biases the lock member 312 in the unlocking direction is interposed between the other end of the lock member 312 and the housing 310. A lever 316 is attached to an intermediate portion of the lock member 312. By rotating the lever 316 around a rotation shaft 320 provided in the housing 310 in one direction (clockwise in the figure), the lock member 312 is moved. It can be operated in the locking direction. When the door is closed, the fitting hole 308 is disposed opposite to the fitting portion 309 of the receiving member 302 fixed to the wall as shown in the figure. In this state, when the lock member 312 is fitted to the fitting portion 309 as shown in FIG. On the other hand, when the lock member 312 is retracted from the fitting portion 309 as shown in FIG.

  The fixed piece 314 has a long shape, and one end portion of the fixed piece 314 is supported by the housing 310 and is disposed to face the fitting portion 313. An actuator 301 is connected to the other end side of the fixed piece 314. When the fixed piece 314 advances toward the lock member 312 and is fitted into the fitting portion 313, the operation of the lock member 312 is fixed. That is, as shown in FIG. 4A, when the fixed piece 314 is fitted to the fitting portion 313 in the locked state, the locked state can be locked. On the other hand, as shown in FIG. 5B, when the fixed piece 314 is retracted from the fitting portion 313, the locked state can be released, and the lock member 312 can be retracted and unlocked. That is, the fixed piece 314 and the actuator 301 constitute an unlocking mechanism of the lock device 300.

  The actuator 301 has a structure similar to the actuator shown in FIG. The action part 130 of the actuating part 330 extends to the opposite side of the transmission part 122 with respect to the rotating shaft 15 and is rotatably connected to the fixed piece 314 at the tip part. A virtual pivot fulcrum 126 is formed at the connecting portion between the transmission portion 122 and the arm portion 118. In such a configuration, the shape memory alloy wire 14 is energized when the locking state of the locking device 300 is unlocked. As a result, the heated shape memory alloy wire 14 is tensioned and contracted, and a rotating moment around the rotating shaft 15 is generated in the operating portion 330. As shown in the figure, the operating part 330 rotates in one direction (clockwise), and as a result, the fixed piece 314 is retracted from the fitting part 313. Thereby, the lock member 312 moves in the unlocking direction by the urging force of the spring 318, and the unlocked state is realized.

  In such an unlocking operation, since the friction state between the fixed piece 314 and the lock member 312 becomes static friction at the start of the operation, a large force is required until the fixed piece 314 starts to be displaced. That is, since the rotational moment becomes maximum at the start of operation, the maximum load (reaction force) acts on the shape memory alloy wire 14. In this respect as well, in this embodiment, as shown in FIG. 5A, the length of the perpendicular line (moment arm) that is applied to the force vector acting on the connecting portion 28 (connecting point) by the operating portion 330 from the rotating shaft 15. Is temporarily increased to suppress the load. For this reason, the lifetime of the shape memory alloy wire 14 can be kept long.

[Fourth embodiment]
FIG. 10 is a diagram illustrating the configuration of the actuator according to the fourth embodiment. (A) shows the overall configuration, (B) shows an enlarged view thereof, and (C) shows an enlarged sectional view thereof.
As shown in FIG. 2A, the actuator 401 of this embodiment includes an actuator body 402 and an energization control device 403 that controls the drive of the actuator body 402. The actuator body 402 is configured by inserting one superelastic alloy wire 412 and one shape memory alloy wire 414 serving as a core into a long flexible tube 410 having flexibility. In this embodiment, the soft tube 410 constitutes the operating part.

  As shown in FIGS. 2B and 2C, the soft tube 410 is made of a flexible resin material such as a silicone resin, and has a plurality of insertion holes through which the wires are inserted along the longitudinal direction thereof. In addition, a plurality of holes forming a space for changing the moment arm are formed to extend in parallel with the insertion hole. That is, the superelastic alloy wire 412 is inserted on one side centered on the axis of the soft tube 410, and the shape memory alloy wire 414 is inserted on the other side. The shape memory alloy wire 414 is inserted so as to be folded at the tip of the soft tube 410, and lead wires are connected to both ends thereof. Both ends of the soft tube 410 are sealed with end members 420 and 422 made of a resin material harder than the soft tube 410. These end members 420 and 422 protect the end portions of the respective wire rods from the outside. In this embodiment, the end member 420 constitutes the base.

  Between the superelastic alloy wire 412 and the shape memory alloy wire 414 of the soft tube 410, a hole 416 extending along both wires is provided, and a first space is formed by the hole 416. Further, a hole 418 extending along the shape memory alloy wire 414 is provided on the opposite side of the shape memory alloy wire 414 from the hole 416, and a second space is formed by the hole 418. In the present embodiment, these hole portions are spaces, but in a modified example, at least one of these hole portions may be filled with a material such as a resin softer than the soft tube 410.

  Since the superelastic alloy wire 412 is made of a superelastic metal, even if the soft tube 410 is bent by an external force, when the external force is released, the elastic return force of the superelastic alloy wire 412 quickly returns to the original linear shape. Try to return.

FIG. 11 is a schematic diagram showing an electrical configuration of the actuator drive control device.
As shown in the figure, the shape memory alloy wire 414 constitutes a part of the control circuit of the actuator 401. A transistor Tr and a resistor R as a wire switch are connected in series to the shape memory alloy wire 414, and a power source 50 is connected in series to the transistor Tr. The transistor Tr serves as a switch for controlling energization to the shape memory alloy wire 414. This energization is controlled by the control unit 52. In this embodiment, an example in which a transistor is used as the wire switch is shown, but an on / off switch that can be manually operated may be used.

  The control unit 52 includes a microcomputer, a CPU that executes various arithmetic processes, a ROM that stores control arithmetic programs and data, a RAM that stores numerical values and flags of arithmetic processes in a predetermined area, and various signals are input and output. An input / output interface is provided. The controller 52 adjusts the duty ratio of the current pulse signal for turning on / off each transistor by so-called PWM control, and controls the amount of current flowing from the power supply 50 to the shape memory alloy wire 414. When the transistor Tr is turned on, the shape memory alloy wire 414 connected in series thereto is energized. The energization current returns through the shape memory alloy wire 414. Since the shape memory alloy wire 414 heated by energization contracts and contracts, the actuator body 402 is bent in a predetermined direction. The control unit 52 performs energization control of the shape memory alloy wire 414 based on an external input.

Next, the operation of the actuator will be described. FIG. 12 is an explanatory diagram showing the operation of the actuator. (A) shows the operation during normal energization, and (B) shows the operation when a restraining force is applied during energization.
Although not shown in the drawing at the time of non-energization, the shape memory alloy wire 14 is in a relaxed and elongated state, so that the actuator body 402 is straightened by the elastic force of the superelastic alloy wire 412 as shown in FIG. It is held in a stretched state.

  When energization is performed from this state, the heated shape memory alloy wire 414 contracts in tension, so that the tension of the shape memory alloy wire 414 increases. As a result, as shown in FIG. 12A, the soft tube 410 is deformed so as to be pulled together with the superelastic alloy wire 412 to the shape memory alloy wire 414 side. That is, a bending moment centering on the base end portion of the superelastic alloy wire 412 is generated, and the actuator body 402 is bent. The bending angle and the like can be changed by adjusting the energization amount to the shape memory alloy wire 414. On the other hand, when energization is interrupted from this state, the shape memory alloy wire 414 is relaxed and extended again. For this reason, the actuator main body 402 is again returned to the state of being straightened by the elastic force of the superelastic alloy wire 412.

  Here, for example, as shown in FIG. 5B, when the tip of the actuator body 402 is restrained and its bending deformation is prevented, if the current is continued as it is, the shape memory alloy wire 414 contracts. Power continues to increase. However, when the contraction force exceeds a predetermined value, the width of the hole 416 increases as shown in the figure, and the shape memory alloy wire 414 is displaced with respect to the soft tube 410 so that the hole 418 is crushed. That is, the distance between the superelastic alloy wire 412 and the shape memory alloy wire 414 changes so as to increase. This is because, when the superelastic alloy wire 412 is regarded as a fulcrum, the length of the perpendicular (moment arm l) taken from the fulcrum to the force vector acting on the connection point between the shape memory alloy wire 414 and the soft tube 410 is large. It means to become.

  That is, the connection point between the shape memory alloy wire 414 and the soft tube 410 is continuously provided along the longitudinal direction of the shape memory alloy wire 414, and each connection point has its longitudinal direction, that is, the shape memory alloy wire. A load acts in the tangential direction of 414. Since a force acts on the connecting point from both sides in the longitudinal direction, the resultant force acts on an action line connecting the connecting point and the fan-shaped center formed by the shape memory alloy wire 414 as shown in the figure. Become. On the other hand, the fulcrum is continuously provided along the longitudinal direction of the superelastic alloy wire 412, and the distance between each fulcrum and each connection point is the moment arm l. In the figure, one of the moment arms 1 is shown. That is, since the moment arm l increases when the load on the shape memory alloy wire 414 increases, the load is suppressed. For this reason, it is possible to prevent the shape memory alloy wire 414 from being broken or deteriorated by such an unexpected load.

  In addition, similar effects can be obtained even during normal energization where no such restraining force is applied. That is, it is assumed that a large bending moment acts on the actuator main body 402 in order to extract a larger amount of displacement of the drive target during energization shown in FIG. Even in such a case, the moment arm l changes according to the increase in the bending moment, and the reaction force against the shape memory alloy wire 414 is suppressed from increasing. As a result, a larger amount of displacement can be ensured without causing substantial damage to the shape memory alloy wire 414.

  The present invention is not limited to the above-described embodiments, and various modifications such as design changes can be added to the embodiments based on the knowledge of those skilled in the art. Embodiments described may also be included within the scope of the present invention.

  The above embodiments are configured as actuators for unlocking mechanisms such as doors and hatches in automobiles, airplanes, ships, railroads, lids for luggage cases attached to motorcycles and bicycles, lids for key boxes in houses, facilities, etc. Can do. Further, it can be configured as a moving illumination, a robot joint, or an actuator of a mechanism part of a personal computer (PC). Even if it is configured as such an actuator, it is possible to obtain a merit such that unlike a solenoid, a force can be exerted to start moving, and even if it is forced to move from the outside, it does not break, so it has excellent safety and durability. In addition, although what contains the shape memory alloy wire mentioned above may be employ | adopted for an actuator, other drive elements, such as a motor, can also be used.

  DESCRIPTION OF SYMBOLS 1 Actuator, 2 Actuator main body, 3 Current supply apparatus, 10 Base, 12 Actuator, 14 Shape memory alloy wire, 15 Rotating shaft, 16 Rotating member, 18 Arm, 20 Acting part, 22 Transmitting part, 24 Acting point, 26 times Moving shaft, 28 connecting portion, 30, 32 spring, 33 stopper, 34 switch, 36, 50 power supply, 52 control portion, 100 actuator, 101 base portion, 102 fulcrum, 103 operating portion, 104 load mechanism, 105 bias mechanism, 106 action Point, 107 connecting point, 112 working part, 114 shape memory alloy wire, 115 working part, 116 rotating part, 118 arm part, 120 working part, 122 transmitting part, 124 shape memory alloy wire, 126 turning fulcrum, 130 working Part, 132 support part, 136 Rotating part, 150 arm, 152 guide rod, 154 connecting part, 156 stopper, 158 elastic member, 201 actuator, 202 first operating part, 204 second operating part, 206 mounting table, 208 guide slit, 210 housing, 211 Guide part, 212 engaging part, 215 rotating shaft, 216 body, 217 connecting part, 218 guide slit, 220 connecting part, 222 guide slit, 224 engaging part, 236 rotating part, 251 actuator, 252 first operating part, 300 lock device, 301 actuator, 302 member, 304 lock body, 306 lock mechanism, 308 fitting hole, 309 fitting portion, 310 housing, 312 lock member, 313 fitting portion, 314 fixing piece, 316 Lever, 318 Spring, 320 Rotating shaft, 330 Actuator, 401 Actuator, 402 Actuator body, 403 Current controller, 410 Soft tube, 412 Super elastic alloy wire, 414 Shape memory alloy wire, 416, 418 Hole, 420 End Part member.

Claims (12)

The base,
A fulcrum fixed to the base;
An operating portion supported by the fulcrum and having an action point at a position spaced from the fulcrum;
A load mechanism that is connected to a connection point that is a power point of the operating unit and generates a driving force at the operating point by applying a load for displacing the operating unit;
A bias mechanism that applies an urging force in a direction to hold the operating portion in a predetermined position against a load by the load mechanism;
The actuating portion is elastically deformed as the load applied by the load mechanism increases, and thereby a moment arm that is a length of a perpendicular line drawn from a force vector acting on the connection point from the fulcrum, An actuator comprising a variable elastic mechanism that autonomously changes in a direction in which a driving force increases. The fulcrum is provided as a rotating shaft fixed to the base,
The operating portion is rotatably supported by the rotating shaft;
The load mechanism can apply a load for rotating the operating unit around the rotation axis,
The variable elastic mechanism is a moment that is a length of a perpendicular line drawn from a vector of force acting on the connection point from the rotating shaft by elastically deforming according to the magnitude of the load applied by the load mechanism. The actuator according to claim 1, wherein the arm is autonomously changed. The operating part is
A main body rotatably supported by the rotating shaft;
A rotation fulcrum provided at a position away from the rotation shaft of the main body;
An arm portion extending from the rotation fulcrum to the vicinity of the rotation shaft;
An elastic part for generating an urging force in a direction to maintain the positional relationship between the main body and the arm part;
Including
A connecting point with the load mechanism is provided on the arm part,
The variable elastic mechanism displaces the arm portion around the rotation fulcrum against the elastic force of the elastic portion so as to change the moment arm according to the magnitude of the load applied by the load mechanism. The actuator according to claim 2.   4. The actuator according to claim 3, wherein the operating portion is formed by integrally forming the main body, the rotation fulcrum, the arm portion, and the elastic portion. The load mechanism is
A wire connected to the operating portion;
A drive unit that applies a tensile load to the operating unit by displacing the wire rod by energization; and
The actuator according to claim 1, comprising: The wire comprises a shape memory alloy that expands and contracts in the longitudinal direction according to the heating state,
The actuator according to claim 5, wherein the driving unit includes an energization heating device electrically connected to the wire.   The actuator according to claim 6, wherein an intermediate portion of the wire is supported by the connection point of the operating portion, and both ends thereof are fixed to the base portion, respectively.   The variable elastic mechanism is configured so that a variable range of the moment arm is set so that a reaction force applied to the wire in a rotational operation process of the operating unit is within a predetermined setting range smaller than a tensile strength of the wire. The actuator according to claim 6 or 7, wherein the actuator is configured. A first rotating shaft fixed to the base as the fulcrum;
A first operating part rotatably supported by the first rotating shaft as the operating part;
A second rotating shaft fixed at a position spaced apart from the first rotating shaft of the base;
A second operating portion rotatably supported by the second rotating shaft and rotating around the second rotating shaft by receiving the rotational force of the first operating portion;
The actuator according to any one of claims 6 to 8, wherein the displacement amount of the wire is amplified in a superimposed manner by the displacement of the first operating portion and the second operating portion. A guide portion provided at a position between the first rotation shaft and the second rotation shaft in the base portion and extending in one direction;
The first operating portion includes a main body rotatably supported by the first rotation shaft, a rotation fulcrum provided at a position away from the first rotation shaft of the main body, and the rotation fulcrum. Extending from the first rotary shaft to the side of the first rotary shaft and provided with a connecting point with the load mechanism, and extending to the opposite side of the first rotary shaft with respect to the pivot fulcrum Including an intermediate arm portion having an engagement portion at the tip portion;
The second operating portion includes a main body extending from the second rotation shaft in the direction of the guide portion, an engaged portion that engages the engaging portion with an intermediate portion of the main body so as to be relatively displaceable, A support portion that supports a predetermined driving target while being engaged with and guided by the guide portion at the distal end portion of the main body,
10. The actuator according to claim 9, wherein the drive target is configured to be displaced in the extending direction of the guide portion by the rotation of the first operation portion and the second operation portion. The operating part is provided as a long flexible member having flexibility,
The load mechanism includes a first wire inserted in the longitudinal direction of the flexible member, and a drive unit that applies a tensile load to the operating unit by displacing the first wire by energization,
The bias mechanism is provided as a second wire made of an elastic material inserted in the longitudinal direction of the flexible member so as to be arranged in parallel with the first wire, and constitutes the fulcrum,
A hole extending along both wires is provided between the first wire and the second wire of the flexible member, and the width of the hole changes when the first wire is displaced. 2. The actuator according to claim 1, wherein the moment arm is configured to change autonomously by performing the operation.   When the second hole extending along the first wire is provided on the side of the flexible member opposite to the second wire of the first wire, and the first wire is displaced The actuator according to claim 11, wherein the moment arm is configured to be further changeable by changing a width of the second hole portion.

Images