JP2018021467A - Actuator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently and stably fix a SMA wire.SOLUTION: An actuator 100 includes a SMA wire 106 formed of a shape memory alloy, a stator 102 over which the SMA wire 106 is put, and a mover 104 opposed to the stator 102 across the SMA wire 106 for moving with the expansion of the SMA wire 106. The stator 102 and the mover 104 formed of aluminum are covered by a first outer shell body 120 and a second outer shell body 110 formed of resin, respectively. On the first outer shell body 120, a conductive terminal member 108 is mounted. The end of the SMA wire 106 is fixed to the terminal member 108.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an actuator using the expansion and contraction force of a shape memory alloy.

When a shape memory alloy is heated, it changes from a martensite phase at room temperature to an austenite phase. In the austenite phase, the shape memory alloy is cured in a predetermined shape. When the temperature decreases, the austenite phase transitions again to the martensite phase. In the martensite phase, the shape memory alloy is softened, so that it is easily deformed by an external force.
An actuator using the shape recovery force of such a shape memory alloy has excellent features in various aspects such as downsizing, light weight, and quietness of the device.

  In Patent Documents 1 to 3, a wire (wire material) is formed of a shape memory alloy, and the wire is expanded and contracted by energization control of the wire. By using the contraction of the wire as power, an actuator that can be driven electrically is constructed. Hereinafter, the wire formed of such a shape memory alloy is referred to as “SMA (Shape Memory Alloy) wire”.

  Both ends of the SMA wire are generally fixed to a power supply terminal by screws. The power supply terminal is fixed to a stator that is a base of the actuator. Since a voltage is applied to the SMA wire, the stator that comes into contact with the SMA wire needs to have heat resistance, thermal conductivity (heat dissipation), and insulation. For these reasons, the stator is often made of aluminum and anodized on the surface.

JP 2014-88811 A Japanese Patent No. 5878869 Japanese Patent No. 5836276

  If the power supply terminal is press-fitted and fixed to the stator, the alumite on the surface layer is scraped off, which may cause dielectric breakdown. For this reason, at present, the power supply terminal and the stator are fixed with an adhesive. However, it is difficult to control the filling amount of the adhesive, and it is difficult to stabilize the product quality. Moreover, it is necessary to ensure the time for drying an adhesive agent.

  Also, screwing may be loosened over time. When the power supply terminal is small, screwing does not work well. There is also a problem that the size of the actuator is limited by the size of the screw.

  The present invention has been completed based on the above-mentioned problem recognition by the present inventor, and its main object is to propose a technique for efficiently and stably fixing an SMA wire.

An actuator according to an aspect of the present invention includes a wire formed of a shape memory alloy, a stator through which the wire is passed, a mover that faces the stator across the wire, and moves by expansion and contraction of the wire, and a stator And an outer shell body that is formed of a material having a lower electrical conductivity and covers the stator, and a terminal member attached to the outer shell body.
The end of the wire is fixed to the terminal member.

  According to the present invention, it becomes easy to fix the SMA wire efficiently and stably.

It is an external appearance perspective view of an actuator. It is a side view of an actuator. It is a disassembled perspective view of an actuator. It is an external appearance perspective view of a fixing component. It is an external appearance perspective view of a moving component. It is sectional drawing in the AA of FIG. It is sectional drawing in the BB line of FIG. It is an external appearance perspective view of the terminal member in a 1st embodiment. It is an external appearance perspective view of the terminal member in 2nd Embodiment. It is an external appearance perspective view of the terminal member in 3rd Embodiment. It is an external appearance perspective view of the terminal member in 4th Embodiment. It is an external appearance perspective view of the terminal member in a 5th embodiment. It is an external appearance perspective view of the actuator in 6th Embodiment. It is an external appearance perspective view of the actuator in 7th Embodiment. It is an external appearance perspective view of the actuator in 8th Embodiment. It is an external appearance perspective view when the 1st outer shell is removed from the actuator in an 8th embodiment.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following description, for the sake of convenience, the positional relationship between the structures may be expressed based on the illustrated state. In the following embodiments and modifications thereof, substantially the same components are denoted by the same reference numerals, and the description thereof may be omitted as appropriate.

FIG. 1 is an external perspective view of the actuator 100. FIG. 2 is a side view of the actuator 100.
Hereinafter, the major axis direction of the actuator 100 is the x axis, the minor axis direction is the y axis, and the height direction of the actuator 100 is the z axis. Although the usage scenes of the actuator 100 are various, the actuator 100 according to the present embodiment is a device that is built in the back side of the touch panel of a laptop PC or tablet PC to create a sense of touch. The actuator 100 is a small part having a size of about 30 mm in the x direction, about 3 mm in the y direction, and about 9 mm in the z direction.

The actuator 100 includes a stator 102 and a mover 104. The stator 102 is fixed to the casing, and the mover 104 moves in the z-axis direction with respect to the stator 102 (details will be described later).
The stator 102 and the moving element 104 are made of aluminum. The stator 102 is covered with a first outer shell 120, and the movable element 104 is covered with a second outer shell 110. Both the first outer shell 120 and the second outer shell 110 are made of resin.

  The stator 102 is fixed to the external member 122 with screws 124. The external member 122 is a component that is fixed to the casing or substrate of the tablet. On the first outer shell 120 that protects the stator 102 and the stator 102, protrusions 112 and depressions 114 are alternately formed. Similarly, the protrusions 116 and the recesses 118 are alternately formed on the movable body 104 and the second outer shell 110 that protects the movable element 104. The moving element 104 is placed on the stator 102 with the protrusion 112 of the stator 102 fitted in the recess 118 of the moving element 104 and the protrusion 116 of the moving element 104 fitted in the indentation 114 of the stator 102. The The displacement of the moving element 104 in the x direction is restricted by the engagement of the protrusion 112 of the stator 102 and the recess 118 of the moving element 104, and the protrusion 116 of the moving element 104 and the indenting 114 of the stator 102.

The mover 104 can move about 50 to 100 μm in the z-axis direction. The moving direction of the moving element 104 may be a horizontal direction with respect to the touch panel surface, or may be a vertical direction with respect to the surface of the touch panel. In the actuator 100 installed on the back side of the touch panel, when the user touches the touch panel, the mover 104 slightly moves in the z-axis direction, and the movement is transmitted to the touch panel. By such a method, a tactile sensation associated with the touch is given to the user.
The mover 104 may push up the touch panel from the back side, or the movement of the mover 104 in the surface direction may give a slight vibration to the touch panel. Various tactile sensations are realized depending on the number, position, and direction of the actuators 100 arranged on the back surface of the touch panel.

The actuator 100 includes a stator 102, a moving element 104, a first outer shell body 120, a second outer shell body 110, an SMA wire 106, and two terminal members 108a and 108b.
The SMA wire 106 is passed between the stator 102 and the moving element 104 (details will be described later). Both ends of the SMA wire 106 are fixed to two terminal members 108a and 108b (hereinafter simply referred to as “terminal members 108” when collectively referred to or not distinguished from each other). The terminal member 108a functions as a current input terminal, and the terminal member 108b functions as a current output terminal. Therefore, the terminal member 108 must be a conductive member. The terminal member 108 in this embodiment is formed of brass or copper.

  A groove 130 (slit) is formed in the terminal member 108 (see FIG. 1). Further, a groove 136 (slit) is also formed in the first outer shell body 120 (see FIG. 1). The groove 130 and the groove 136 are formed so as to be aligned. The SMA wire 106 passes through the groove 136 of the first outer shell 120 and the groove 130 of the terminal member 108. Since the groove 130 and the groove 136 are aligned in a straight line, the SMA wire 106 is easily passed between the two grooves 130 and 136. By crushing the groove 130 of the terminal member 108, the end portion of the SMA wire 106 is caulked and fixed to the terminal member 108. When a current is passed from the terminal member 108 to the SMA wire 106, the SMA wire 106 is heated to a high temperature, undergoes a phase transition to an austenite phase, and is cured and elongated. Due to the hardening and extension of the SMA wire 106, the moving element 104 is displaced in the positive z-axis direction. Details of the mechanism for converting the expansion and contraction of the SMA wire 106 into the movement of the moving element 104 in the z direction will be described later.

  A concave portion 140 is formed on the side surface of the first outer shell 120, and the terminal member 108 has a convex portion 138. The terminal member 108 is fixed to the first outer shell 120 by fitting the concave portion 140 and the convex portion 138 together. In order to fix the terminal member 108 to the first outer shell 120, an adhesive or a screw is unnecessary. The convex portion 138 may be formed on the first outer shell 120 and the concave portion 140 may be formed on the terminal member 108. Two or more pairs of the convex part 138 and the concave part 140 may be sufficient.

  The terminal members 108a and 108b are in contact with spring terminals 142a and 142b having elasticity. The two terminal member spring terminals 142a and 142b (hereinafter simply referred to as “spring terminals 142” when collectively referred to or not particularly distinguished) are electrically conductive fixed to the tablet casing or substrate, as with the external member 122. It is a part of.

When a current is passed through the spring terminal 142a, a current flows through the SMA wire 106 via the terminal member 108a, and the SMA wire 106 generates heat. It is desirable that the stator 102 and the mover 104 that are in contact with most of the SMA wire 106 be formed of a material having excellent heat resistance and thermal conductivity. In order to prevent leakage of current flowing through the SMA wire 106, the stator 102 and the mover 104 are preferably insulating members. In the present embodiment, the stator 102 and the mover 104 are made of aluminum having excellent heat resistance and thermal conductivity. Since aluminum is a conductor, insulation is ensured by subjecting the surface of the moving element 104 of the stator 102 to alumite processing.
Anodizing is a process of forming a thin aluminum oxide film (insulating film) on the surface of aluminum. The film thickness of the aluminum oxide film is about 20 to 40 μm.

FIG. 3 is an exploded perspective view of the actuator 100.
The configuration of the actuator 100 is roughly divided into a fixed component 144, a moving component 146, and an SMA wire 106.
The fixed component 144 is a part including the first outer shell 120, the stator 102, and the terminal member 108. First, the stator 102 and the two terminal members 108 are formed, and the first outer shell 120 is formed by a resin insert using these as a part of the mold. By such a manufacturing method, the stator 102 and the terminal member 108 are connected by the first outer shell body 120. Similarly, the second outer shell body 110 is formed by inserting resin with the mover 104 as a part of the mold.

  The moving component 146 is fitted to the fixed component 144 in a state where the SMA wire 106 at room temperature is placed on the fixed component 144. Thereafter, both ends of the SMA wire 106 are fixed by crimping with the terminal member 108a and the terminal member 108b. More specifically, the SMA wire 106 is crimped to the terminal member 108 by crushing the groove 130 from both sides while the SMA wire 106 is passed through the groove 130 of the terminal member 108.

Since it is insert molding, the 1st outer shell 120 is easy to form in a shape more complicated than stator 102. In other words, it is easy to simplify the shape of the stator 102 and the terminal member 108. As described above, since the stator 102 in contact with the SMA wire 106 is required to have heat dissipation and insulation, a thin aluminum oxide film is formed on the surface of the stator 102. When the terminal member 108 is attached directly to the stator 102, there is a risk that the terminal member 108 may damage the aluminum oxide film in the attaching process. In the present embodiment, the stator 102 is protected by the insulating first outer shell 120, and the terminal member 108 is attached to the first outer shell 120. There is an advantage that no stress is applied to the aluminum oxide film of the stator 102 in the manufacturing process.
The same applies to the mover 104 and the second outer shell 110.

The terminal member 108 is separated from the stator 102 by the first outer shell body 120 and is also separated from the mover 104. For this reason, the current does not leak from the terminal member 108 to the stator 102 or the moving element 104. Even if a part of the aluminum oxide film of the stator 102 is damaged, there is no possibility that the terminal member 108 contacts there.
The first outer shell body 120 and the second outer shell body 110 are preferably members having insulating properties, but are preferably formed of a substance having a lower electrical conductivity than at least the stator 102 and the moving element 104. .

  The second outer shell 110 has protrusions 148 at both ends. The 1st outer shell 120 has the accommodating part 150 in both ends. By pressing the moving component 146 from above the fixed component 144, the protruding portion 148 is fitted into the accommodating portion 150. At the time of fitting, the groove 136 of the housing part 150 slightly expands in the lateral direction (y direction), so that the protrusion 148 can be easily pushed into the housing part 150. The groove 136 of the first outer shell 120 has an effect of facilitating not only the alignment of the SMA wire 106 but also the fitting operation.

  By fitting the protruding portion 148 and the housing portion 150, the fixed component 144 (first outer shell body 120) and the moving component 146 (second outer shell body 110) are fixed to each other. However, since there is a margin (play) in the fitting between the protrusion 148 and the housing 150, the moving component 146 can move in the z-axis direction with respect to the fixed component 144 even during fitting. Details of the fitting structure between the projection 148 and the housing 150 will be described later.

  In the first outer shell 120, a heat radiation hole 152 is formed in a portion corresponding to the protrusion 112 of the stator 102. A heat radiation protrusion 154 is formed on the stator 102 corresponding to the heat radiation hole 152. The heat radiation protrusion 154 is exposed from the heat radiation hole 152 (see FIGS. 1 and 2). Part of the heat transmitted from the SMA wire 106 to the stator 102 is transmitted to the external member 122, and part of the heat is radiated from the heat radiation holes 152 to the atmosphere.

  Similarly, in the second outer shell body 110, a heat radiation hole 156 is formed in a portion corresponding to the protrusion 116 of the moving element 104. A heat dissipation protrusion 158 is formed on the moving element 104 corresponding to the heat dissipation hole 156. The heat radiation protrusion 158 is exposed from the heat radiation hole 156. Further, the upper part of the second outer shell 110 is open, and the upper surface of the movable element 104 is exposed. The heat transmitted from the SMA wire 106 to the moving element 104 is radiated from the upper surface of the moving element 104 and the heat radiation protrusion 158.

  As described above, the heat of the SMA wire 106 is easily escaped from the stator 102 and the mover 104 having high thermal conductivity to help the SMA wire 106 quickly return to normal temperature when energization is stopped. By providing the heat dissipation protrusions 158, the volume of the aluminum stator 102 can be increased. The larger the volume of the stator 102, the easier the heat of the SMA wire 106 is absorbed. Providing the heat radiation hole 156 and the heat radiation projection 158 near the SMA wire 106 as a heat source is also effective for quickly releasing the heat of the SMA wire 106 to the outside air.

FIG. 4 is an external perspective view of the fixed component 144. FIG. 5 is an external perspective view of the moving component 146.
At normal temperature, the SMA wire 106 is passed over the stator 102 along the protrusion 112 and the recess 114. A wall portion 128 is formed by the first outer shell 120 on the protrusion 112 of the stator 102. In the groove 126 between the walls 128, the stator 102 is exposed. Similarly, the wall portion 134 is also formed by the second outer shell 110 in the protrusion 116 of the movable element 104 (see FIG. 5). In the groove 132 formed by the wall portion 134, the movable element 104 is exposed. That is, the SMA wire 106 contacts the stator 102 in the groove 126 and contacts the moving element 104 in the groove 132.

  In the protrusion 112 of the stator 102 (indentation 118 of the moving element 104), the SMA wire 106 passes over the groove 126 of the stator 102 and in the indentation 114 of the stator 102 (indentation 116 of the moving element 104), The SMA wire 106 passes under the groove 132 of the moving element 104. The wall portion 128 of the stator 102 and the wall portion 134 of the moving element 104 restrict the displacement of the SMA wire 106 in the left-right direction, thereby preventing the SMA wire 106 from being detached from the actuator 100.

6 is a cross-sectional view taken along line AA in FIG. 7 is a cross-sectional view taken along line BB in FIG.
When power is supplied from the spring terminal 142 to the terminal member 108, a current flows through the SMA wire 106. When a current flows through the SMA wire 106, the SMA wire 106 undergoes a phase transition to the austenite phase and hardens, and tends to extend linearly. When the SMA wire 106 is extended, the movable element 104 is pushed upward (z-axis positive direction).

  The protrusion 148 is freely fit in the receiving portion 150. Specifically, a margin 160 is provided in the fitting portion so that the protrusion 148 can move in the z-axis direction (fitting direction) (see FIG. 7). It is desirable to form a margin 160 of about 50 to 100 μm in the z-axis direction. The size of the margin 160 in the z-axis direction defines the maximum amount of movement of the moving element 104.

  When the power supply is stopped, the SMA wire 106 becomes a low temperature and phase transitions to the martensite phase and softens, so that the moving element 104 returns downward (z-axis negative direction). When the power supply is stopped, the heat of the SMA wire 106 is released to the stator 102 and the moving element 104, and the SMA wire 106 quickly returns to room temperature.

  More specifically, when a touch on the touch panel is detected by the sensor, a control circuit (not shown) supplies power to the terminal member 108 for a short time. At this time, since the SMA wire 106 once transits to the austenite phase and then to the martensite phase, the finger touching the touch panel feels a temporary physical repulsive force. With such a control method, a touch feeling similar to that of a keyboard can be realized even with a touch panel.

  When the terminal member 108 is fixed to the stator 102 or the moving element 104 with screws, the workability deteriorates when the terminal member 108 is small. Further, the size of the terminal member 108 is restricted by the size of the screw. Even when fixed with an adhesive, the workability is poor and the production quality is not stable. When the terminal member 108 is press-fitted and fixed to the stator 102 or the mover 104, there is a risk that the aluminum oxide film may be partially broken due to stress during press-fitting. Since aluminum is conductive, if the aluminum oxide film is broken, the current flowing through the terminal member 108 leaks to the stator 102.

  In the present embodiment, the first outer shell body 120 is formed by insert molding by using the stator 102 and the terminal member 108 as a mold. Similarly, the second outer shell 110 is formed by insert molding by using the moving element 104 as a mold. The terminal member 108 is fixed to the insulating first outer shell 120 instead of the stator 102 and the moving element 104. The merits of such a manufacturing method are as follows: (1) The aluminum oxide film of the stator 102 is hardly damaged. (2) Since the first outer shell body 120 is insert-molded, the shape of the stator 102 and the first outer shell body 120. (3) The first outer shell 120 and the terminal member 108 can be securely and easily fixed. (4) The terminal member 108 is separated from the stator 102 and the moving element 104 by the insulating first outer shell 120. Therefore, current leakage of the terminal member 108 is less likely to occur.

(First embodiment)
FIG. 8 is an external perspective view of the terminal member 108 in the first embodiment.
The terminal member 108 has grooves 130a and 130b on the upper and lower surfaces. The SMA wire 106 is inserted into the groove 130a on the upper surface, and the SMA wire 106 is caulked and fixed by the groove 130a. Although the groove 130 is formed on the upper surface of the terminal member 108 in FIG. 8, the groove 130 may be formed on the side surface of the terminal member 108.

  A base component 162 (external member) is inserted into the groove 130b on the lower surface. The pedestal component 162 is a component that is fixed to the tablet casing or substrate. The pedestal component 162 may be a power supply terminal, and the insertion portion (projection) of the groove 130b may have elasticity due to a spring structure or the like.

  A convex portion 138 is formed on the side surface of the terminal member 108, and a through hole 164 is formed in the convex portion 138. As shown in FIG. 1, the convex portion 138 is fitted with the concave portion 140 of the first outer shell body 120. When insert molding the first outer shell body 120, the resin enters the through-hole 164, so that the terminal member 108 and the first outer shell body 120 are strongly coupled.

  As shown in FIG. 8, the terminal member 108 may be formed in a vertically symmetrical shape. If the terminal member 108 is vertically symmetrical, the actuator 100 can be manufactured more easily because it is not necessary to care about the upper and lower sides of the terminal member 108.

(Second Embodiment)
FIG. 9 is an external perspective view of the terminal member 108 in the second embodiment.
In the terminal member 108 in the second embodiment, a through hole 166 is formed not only in the convex portion 138 but also in the main body portion. Resin may be inserted also into this through-hole 166, and components, such as a screw, may be inserted. A pin-shaped electrode may be inserted into the through hole 166. Also in the second embodiment, the groove 130 and the through hole 166 may be formed so as to be vertically symmetrical. For example, the groove 130 and the through hole 166 may be formed above the convex portion 138, and the groove 130 and the through hole 166 may be formed below the convex portion 138.

(Third embodiment)
FIG. 10 is an external perspective view of the terminal member 108 in the third embodiment.
The terminal member 108 of the third embodiment is formed with a through hole 170 that penetrates the terminal member 108 in the z-axis direction. A screw 168 is inserted into the upper surface of the terminal member 108. In the third embodiment, the SMA wire 106 is fixed to the terminal member 108 by sandwiching the SMA wire 106 with the screw 168 and the terminal member 108, instead of crimping the SMA wire 106 with the groove 130.

The screw 168 may be inserted into the terminal member 108 with the SMA wire 106 wound around the screw 168. A pin-shaped member may be press-fitted into the through-hole 170 instead of the screw 168. Although it is not essential to wind the SMA wire 106 around the screw 168, it is easier to fix the SMA wire 106 to the terminal member 108 more reliably by winding it once or more.
Resin may be inserted from the lower part of the through-hole 170, and components, such as a screw | thread, may be inserted. A pin-shaped electrode may be inserted.

(Fourth embodiment)
FIG. 11 is an external perspective view of the terminal member 108 in the fourth embodiment.
The groove 130 may be formed in the upper part of the terminal member 108, and the accommodation hole 172 may be formed in the lower part of the terminal member 108. Resin may be inserted into the accommodation hole 172, or a component such as a screw may be inserted. A pin-shaped electrode may be inserted.

(Fifth embodiment)
FIG. 12 is an external perspective view of the terminal member 108 in the fifth embodiment.
In the fifth embodiment, the groove 130 is formed on the side surface of the terminal member 108. When the groove 130 is formed on the side surface, the SMA wire 106 is caulked and fixed by pressing the upper surface of the terminal member 108. A connecting member 174 is fixed to the through hole 166 formed in the main body of the terminal member 108. The connection member 174 is a component for connecting the external component and the terminal member 108. Electric power may be supplied to the terminal member 108 via the connection member 174.

(Sixth embodiment)
FIG. 13 is an external perspective view of the actuator 100 according to the sixth embodiment.
In the sixth embodiment, a protrusion 176 is formed on the first outer shell 120, and an accommodating portion 178 is formed on the second outer shell 110. When the flange portion 182 of the housing portion 178 is engaged with the flange portion 180 of the projection portion 176, the movable element 104 (second outer shell body 110) is fixed to the stator 102 (first outer shell body 120). When the second outer shell body 110 and the first outer shell body 120 are fitted, a margin similar to that in FIG. 7 is provided between the flange portion 180 and the flange portion 182. For this reason, when the SMA wire 106 extends, the movable element 104 moves in the z-axis direction. A groove 136 is formed at the center of the protrusion 176, and the SMA wire 106 is inserted into the groove 136.

  When the second outer shell 110 is fitted into the first outer shell 120, the protrusion 176 is pushed inwardly of the groove 136 of the first outer shell 120. For this reason, the projection part 176 and the collar part 182 can be fitted smoothly. Moreover, since the projection part 176 of the 1st outer shell 120 returns outside by an elastic force after fitting, the fitting of the projection part 176 and the collar part 182 can be stabilized.

(Seventh embodiment)
FIG. 14 is an external perspective view of the actuator 100 according to the seventh embodiment.
In the seventh embodiment, a protrusion 184 is formed on the side of the second outer shell 110, and a restricting portion 186 (accommodating portion) is formed on the first outer shell 120. A margin 188 is formed between the protruding portion 184 and the restricting portion 186. The first outer shell body 120 and the second outer shell body 110 are fitted (freely fitted) by pushing the protrusion 184 into the restricting portion 186 having a relatively high elastic modulus. Also in the seventh embodiment, the groove 130 is formed in the center of the restricting portion 186.

(Eighth embodiment)
FIG. 15 is an external perspective view of the actuator 100 according to the eighth embodiment. FIG. 16 is an external perspective view when the first outer shell 120 is removed from the actuator 100 according to the eighth embodiment.
In the eighth embodiment, the actuator 100 is fixed to an external member 194. The fixing method may be any method such as screw fixing or adhesive. A first pin 192 having a cross-sectional area that is much smaller than the bottom area of the terminal member 108, preferably 10% or less of the maximum cross-sectional area in the xy plane of the terminal member 108, on the bottom surface of the terminal member 108 (head). Are connected (see FIG. 16). The first pin 192 is connected to the second pin 190 having a diameter larger than that of the first pin 192, and the second pin 190 penetrates the member 194. Second pin 190 is soldered to member 194 at weld area 196.

  In the eighth embodiment, first, the first outer shell 120 is insert-molded using the terminal member 108 and the stator 102 as a part of the mold. Next, the second outer shell body 110 is insert-molded on the moving element 104. After the SMA wire 106 is inserted, the second outer shell body 110 and the first outer shell body 120 are fitted by the same fitting method as in the first embodiment. The SMA wire 106 is caulked and fixed to the terminal member 108. The actuator 100 formed in this way is fixed to the member 194. At this time, the second pin 190 is fixed to the member 194 by soldering the welding region 196.

  Since the temperature of the solder at the time of welding is 200 ° C. or more, when the heat of the solder is transmitted to the SMA wire 106, a force that strongly extends the SMA wire 106 is generated. In the eighth embodiment, since the terminal member 108 and the welding region 196 are connected via the second pin 190 and the first pin 192 having a small diameter, the heat of solder is hardly transmitted to the terminal member 108. Since heat does not easily conduct through the first pins 192, most of the heat of the solder escapes to the member 194. According to such a structure, workability | operativity when using the solder and fixing the actuator 100 can be improved.

The actuator 100 driven by 106 has been described above based on the embodiment.
Since the first outer shell body 120 and the second outer shell body 110 are formed of a resin with good processability, the stator 102, the movable element 104, and the terminal member 108 can have a relatively simple structure. Since the terminal member 108 is separated from the stator 102 and the moving element 104 by the first outer shell body 120 and the second outer shell body 110, the leakage from the terminal member 108 to the stator 102 and the like can be prevented. Further, the first outer shell body 120 and the second outer shell body 110 protect the aluminum oxide film such as the stator 102.

  Since the terminal member 108 is fixed to the first outer shell 120 at the time of insert molding, the terminal member 108 and the stator 102 can be connected to the first outer shell 120 efficiently and stably. The same applies to the second outer shell 110. Since the resin has good processability and moderate elasticity, the protruding portion 148 and the accommodating portion 150 can be fitted with one touch. Processing such as cutting a screw groove in the stator 102 or the like is unnecessary, and an adhesive is not essential, so that workability is excellent. In particular, this is an effective fixing method for the small actuator 100 of about several mm.

  In the case of the SMA wire 106, the stator 102 preferably has heat resistance, thermal conductivity, and insulation. Aluminum has heat resistance and is excellent in thermal conductivity but has conductivity. Therefore, insulation is realized by anodizing the surface of the SMA wire 106. Since the aluminum oxide film formed by anodizing is thin, a manufacturing method that may scrape the surface of the stator 102 is not desirable. In this embodiment, since the stator 102 is protected by the first outer shell body 120 and the terminal member 108 is fixed to the first outer shell body 120, the aluminum oxide coating is not burdened.

  The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the specific embodiments, and various modifications can be made within the scope of the technical idea of the present invention. Nor. For example, some components may be combined in the above-described embodiment and modification, or some components may be deleted from each embodiment and modification.

  In the present embodiment, it has been described that the wall portions 128 are formed on both side surfaces of the contact portion (groove 126) of the SMA wire 106 in the stator 102. The same applies to the mover 104. The wall portion 128 in the stator 102 and the wall portion 134 in the movable element 104 may be formed only on one side. Only the wall portion 128 of the stator 102 may be formed, or only the wall portion 134 of the movable element 104 may be formed.

  Although it is desirable that the first outer shell body 120 and the second outer shell body 110 are formed with respect to the stator 102 and the moving element 104, only one of the first outer shell body 120 and the second outer shell body 110 is formed. It may be formed. For example, the projecting portion 148 may be formed on the moving element 104 itself, and the accommodating portion 150 may be formed on the first outer shell body 120. Alternatively, the projecting portion 148 may be formed on the second outer shell body 110, and the accommodating portion 150 may be formed on the stator 102 itself.

  Since the SMA wire 106 needs to be promptly cooled when the energization is stopped, it is desirable that the stator 102 and the moving element 104 be made of a material having a high thermal conductivity. In the present embodiment, the stator 102 and the mover 104 have been described as being aluminum, but may be formed of a material having a thermal conductivity equal to or higher than a predetermined value, such as a metal or a carbon nanotube. The present invention is particularly effective when the surface of such a substance is plated to ensure insulation.

The following inventions can be recognized from the above embodiments.
B1. A wire formed of a shape memory alloy;
A stator through which the wire is passed,
A mover that faces the stator across the wire and moves by expansion and contraction of the wire,
An actuator comprising: a first outer shell formed of resin and covering the stator.

B2. The actuator according to B1, wherein the wire is supplied with electric power from a terminal member fixed to the first outer shell.

B3. The first outer shell body exposes the stator at a contact portion of the wire with the stator, and forms wall portions on both sides or one side of the contact portion. Actuator.

B4. The actuator according to any one of B1 to B3, wherein the first outer shell body is formed by insert molding a resin.

B5. Protrusions and depressions are alternately formed on both the stator and the mover,
The movable element is placed on the stator in a state where the depression of the movable element is opposed to the protrusion of the stator, and the protrusion of the movable element is opposed to the depression of the stator.
From B1, the first outer shell body exposes the stator at a contact portion of the wire with the stator, and also exposes the stator at a side portion of the protrusion. The actuator according to any one of B4.

B6. The actuator according to B1, further comprising: a second outer shell body that is made of resin and covers the moving element.

B7. Protrusions and depressions are alternately formed on both the stator and the mover,
The movable element is placed on the stator in a state where the depression of the movable element is opposed to the protrusion of the stator, and the protrusion of the movable element is opposed to the depression of the stator.
The first outer shell body exposes the stator at a contact portion of the wire with the stator, and forms wall portions on both sides or one side of the contact portion;
The second outer shell body exposes the mover at a contact portion of the wire with the mover, and forms wall portions on both sides or one side of the contact portion. Actuator.

Furthermore, the following invention can be recognized.
C1. A wire formed of a shape memory alloy;
A stator through which the wire is passed,
A mover that faces the stator across the wire and moves by expansion and contraction of the wire,
A first outer shell covering the stator;
A second outer shell covering the moving element,
An actuator characterized in that the first and second outer shells are connected to each other in a state where the movable element is movable by fitting the first and second outer shells.

C2. In a state where the first outer shell body is provided with a margin capable of moving in the fitting direction, a protrusion formed on one of the first and second outer shell bodies is used as a housing portion formed on the other. The actuator according to C1, wherein the actuator is fitted.

C3. The actuator according to C2, wherein a slit is formed in both or one of the protruding portion and the accommodating portion.

C4. A terminal member attached to the first outer shell body and fixing an end of the wire;
A slit is formed in both the first outer shell body and the terminal member, and the slit of the first outer shell and the slit of the terminal member are formed to be aligned. The actuator according to C1.

  DESCRIPTION OF SYMBOLS 100 Actuator, 102 Stator, 104 Mover, 106 SMA wire, 108 Terminal member, 110 2nd outer shell body, 112 Protrusion, 114 hollow, 116 Protrusion, 118 hollow, 120 1st outer shell body, 122 External member, 124 Screw, 126 groove, 128 wall part, 130 groove, 132 groove, 134 wall part, 136 groove, 138 convex part, 140 concave part, 142 spring terminal, 144 fixing part, 146 moving part, 148 protruding part, 150 receiving part, 152 Radiating holes, 154 radiating projections, 156 radiating holes, 158 radiating projections, 160 margin, 162 base parts, 164 through holes, 166 through holes, 168 screws, 170 through holes, 172 receiving holes, 174 connecting members, 176 projecting parts, 178 Receiving part, 180 collar part, 182 collar part, 184 projection part, 86 restricting portion 188 margin, 190 second pin 192 first pin, 194 members, 196 weld area.

Claims (6)

A wire formed of a shape memory alloy;
A stator through which the wire is passed,
A mover that faces the stator across the wire and moves by expansion and contraction of the wire,
An outer shell formed of a material having a lower electrical conductivity than the stator, and covering the stator;
A terminal member attached to the outer shell body,
The actuator is characterized in that an end portion of the wire rod is fixed to the terminal member.   The actuator according to claim 1, wherein the wire is fixed by crimping at the terminal member. A groove is formed in the outer shell and the terminal member,
The wire is inserted into the grooves of both the outer shell and the stator,
The actuator according to claim 2, wherein the wire is crimped and fixed on the terminal member by pressing the groove of the terminal member. The terminal member has grooves formed on both the upper and lower parts,
The wire is inserted into the groove at the top of the terminal member,
The actuator according to any one of claims 1 to 3, wherein a convex portion of an external member is inserted into the groove below the terminal member.   The said terminal member has the head part which fixes the edge part of the said wire, and the pin part extended | stretched from the said head and connected to an external member, The Claim 1 characterized by the above-mentioned. Actuator.   A concave portion is formed on one of the outer shell body and the terminal member, and a convex portion is formed on the other, and the terminal member is attached to the outer shell body by fitting the concave portion and the convex portion. Item 6. The actuator according to any one of Items 1 to 5.

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