JP7114087B2 - Actuator and actuator manufacturing method - Google Patents

Description

The present invention relates to actuators and methods of manufacturing actuators.

A pulse voltage is applied to a wire made of a shape memory alloy that is threaded between multiple cylinders made of thermally conductive material that are arranged in parallel. It is disclosed (Patent Document 1). The Joule heat generated in the wire quickly diffuses through the cylinder, and the wire length is restored. As a result, the cylinder quickly returns to its original position.

WO2012/023605

However, in the actuator disclosed in Patent Document 1, the ends of the wires are fixed by screws. The task of fixing thin wires with screws is highly difficult and unsuitable for mass production.

An object of one aspect is to provide an actuator or the like that can easily fix a shape memory alloy wire.

The actuator is disposed between a stator having a plurality of rotatably supported stator rollers and fixed terminals respectively disposed on both sides in the arrangement direction of the stator rollers, and the stator rollers. A mover having a mover roller rotatably supported in a cage, a wire made of a shape memory alloy sandwiched between the stator roller and the mover roller, and both ends of the wire connected to the fixed terminals. Each of the terminal plates is crimped and fixed, and the crimped portion of the terminal plate has recesses formed on both sides of the portion corresponding to the wire so that the portion corresponding to the wire is aligned in parallel with the wire. A portion having a raised shape and corresponding to the wire is recessed with respect to the surface of the terminal plate.

In one aspect, it is possible to provide an actuator or the like that can easily fix a shape memory alloy wire.

FIG. 4 is a perspective view of an actuator; 4 is an exploded perspective view of an actuator; FIG. It is a perspective view of a stator. It is a top view of a stator. 5 is a cross-sectional view taken along line V-V of FIG. 4; FIG. It is a perspective view of a mover. Fig. 10 is a perspective view of a fastener; It is explanatory drawing explaining the assembly process of an actuator. It is explanatory drawing explaining the assembly process of an actuator. It is explanatory drawing explaining the assembly process of an actuator. It is explanatory drawing explaining the assembly process of an actuator. It is explanatory drawing explaining the assembly process of an actuator. FIG. 12 is an enlarged view of part A in FIG. 11; 13 is an enlarged view of a B portion of FIG. 12; FIG. FIG. 4 is a top view of an actuator; FIG. 16 is a cross-sectional view taken along line XVI-XVI of FIG. 15; FIG. 16 is a sectional view along line XVII-XVII of FIG. 15; 15. It is sectional drawing by the XVIII-XVIII line of FIG. FIG. 16 is a cross-sectional view taken along line XIX-XIX of FIG. 15; FIG. 4 is an explanatory diagram for explaining the operating state of an actuator; FIG. 18 is an enlarged view of part C in FIG. 17; FIG. 11 is an explanatory diagram for explaining a state in which the mover is shifted to the left; FIG. 8 is an exploded perspective view of an actuator according to Embodiment 2; 8 is a cross-sectional view of an actuator according to Embodiment 2; FIG. FIG. 11 is a perspective view of a stator according to Embodiment 3; FIG. 8 is a cross-sectional view of an actuator according to Embodiment 3; FIG. 11 is a perspective view of a stator according to Embodiment 4; FIG. 11 is a cross-sectional view of a stator according to Embodiment 4; FIG. 11 is a perspective view of a mover according to Embodiment 4; FIG. 11 is a front view of a stator roller according to Embodiment 5; FIG. 11 is a cross-sectional view of an actuator according to Embodiment 5; FIG. 11 is an exploded perspective view of an actuator according to Embodiment 6; FIG. 21 is a perspective view of an actuator from which a fastener and a mover of Embodiment 6 are removed; FIG. 20 is a partially enlarged cross-sectional view of the actuator from which the fastener and the slider of Embodiment 6 are removed;

[Embodiment 1]
FIG. 1 is a perspective view of the actuator 10. FIG. The following description uses the front, back, left, right, up and down directions indicated by arrows in each figure. The actuator 10 has a substantially rectangular parallelepiped shape that is elongated in the left-right direction, and has a plane-symmetrical shape in the front-rear direction and the left-right direction. The actuator 10 is incorporated inside a device such as a smart phone or a tablet, as described later, and allows a user touching the device to feel a tactile sensation such as a click feeling.

FIG. 2 is an exploded perspective view of the actuator 10. FIG. Actuator 10 has stator 20 , mover 40 and fastener 50 . The stator 20 has a stator frame 21 , fixed terminals 22 and five stator rollers 23 . The mover 40 has a mover frame 41 and four mover rollers 42 . The fastener 50 has four urging springs 51 that press the mover 40 against the stator 20 . Details of the configurations of the stator 20, the mover 40, and the fastener 50 will be described later.

FIG. 3 is a perspective view of the stator 20. FIG. 4 is a top view of the stator 20. FIG. 5 is a cross-sectional view taken along line V-V of FIG. 4. FIG. The configuration of the stator 20 will be described using FIGS. 2 to 5. FIG.

The stator rollers 23 are cylindrical. The stator roller 23 has a cylindrical stator shaft portion 231 coaxially protruding from both end faces. That is, the stator roller 23 has a stepped columnar shape having stator shaft portions 231 at both ends that are narrower than the central portion.

The stator rollers 23 are made of a material with high thermal conductivity. The material of the stator roller 23 is, for example, metal such as aluminum or copper, or ceramics such as aluminum nitride or silicon nitride. The stator roller 23 may be made of resin.

The stator frame 21 is a substantially rectangular frame elongated in the left-right direction, and has five pairs of roller support portions 25 on the inner surfaces of the front and rear walls. The roller support portions 25 are substantially U-shaped grooves that open upward, and are opposed to each other in pairs. The width of the opening of the roller support portion 25 is slightly wider than the diameter of the stator shaft portion 231 . One stator roller 23 is rotatably supported by a pair of opposing roller support portions 25 .

A front wall and a rear wall of the stator frame 21 are connected via a plurality of connecting portions 28 . The connection portion 28 is positioned below the roller support portion 25 . The connecting portion 28 prevents deformation such that the stator frame 21 expands in the front-rear direction.

Approximately rectangular parallelepiped fastener support portions 26 protrude upward from the four corners of the upper surface of the stator frame 21 . The projection heights of the four fastener support portions 26 are the same. Approximately rectangular parallelepiped fastener fixing protrusions 24 are provided on the outer surface of the central portion of the front wall and the rear wall of the stator frame 21 . The stator frame 21 is made of an insulating material such as resin or ceramics.

The fixed terminals 22 are provided at both left and right ends of the stator frame 21 . The fixed terminal 22 has rectangular terminal plate portions 223 extending outward from both left and right ends of the upper surface of the stator frame 21 . Terminal leg portions 222 extend downward from the front and rear sides of terminal plate portion 223 . A shallow recessed terminal recess 221 is provided in the central portion of the terminal plate portion 223 .

The fixed terminal 22 is formed by bending a highly conductive metal plate such as brass or phosphor bronze. The surface of the fixed terminal 22 is covered with a layer that can be easily soldered, such as a tin-plated layer or a gold-plated layer. The two fixed terminals 22 are insulated from each other. The two fixed terminals 22 are integrated with the stator frame 21 by insert molding.

It is desirable that the height of the upper surfaces of the left and right terminal plate portions 223 and the height of the upper ends of the five stator rollers 23 are substantially the same. The reason will be described later.

FIG. 6 is a perspective view of the mover 40. FIG. The configuration of the mover 40 will be described with reference to FIGS. 2 and 6. FIG.

The mover roller 42 is cylindrical. The mover roller 42 has a cylindrical mover shaft portion 421 coaxially protruding from both end faces. The mover roller 42 is made of a material with high thermal conductivity.

The slider frame 41 has a top plate portion 47 and four rectangular box-shaped roller holding portions 44 . The top plate portion 47 has a substantially rectangular plate shape with substantially the same dimensions as the stator frame 21 in the front-rear direction and shorter than the stator frame 21 in the left-right direction. The roller holding portions 44 are arranged in a line in the left-right direction on the lower surface of the top plate portion 47 with the openings facing downward. A first wire passage groove 46 is provided in each center of the right wall and the left wall of the roller holding portion 44 .

Roller holding grooves 45 are provided in the front wall and the rear wall of the slider frame 41 . The roller holding groove 45 is substantially U-shaped, and the opening is narrowed to form a stopper. The width of the roller holding groove 45 is slightly wider than the diameter of the mover shaft portion 421 . Mover frame 41 is made of an insulating material such as resin or ceramics.

One movable roller 42 is rotatably held inside the roller holding portion 44 by a pair of opposing roller holding grooves 45 . The mover roller 42 does not fall off even when the mover 40 is held with the top plate portion 47 facing upward due to the retaining action provided at the inlet portion of the roller holding groove 45 .

As shown in FIGS. 1 and 2, two substantially rectangular parallelepiped pressing portions 43 are provided on the upper surface of the top plate portion 47 so as to be arranged side by side in the left-right direction. The protrusion heights of the two pressing portions 43 are the same.

7 is a perspective view of the fastener 50. FIG. Details of the configuration of the fastener 50 will be described with reference to FIG. The fastener 50 has two side plate portions 52 facing each other in the front-rear direction. The side plate portion 52 has a substantially rectangular shape elongated in the left-right direction. The front and rear side plate portions 52 are connected by a connecting portion 54 that spans the central portion and a support plate portion 55 that spans the left and right ends.

The connecting portion 54 is substantially rectangular, and two tapered urging springs 51 extend from the left and right edges. The biasing spring 51 gently bends downward and bends upward in the vicinity of the tip. As described above, a total of four urging springs 51 are configured on the left and right sides of the connecting portion 54 . The function of the urging spring 51 will be described later.

The support plate portion 55 is substantially rectangular. The two supporting plate portions 55 and the connecting portion 54 are on the same plane. A long mounting hole 53 elongated in the left-right direction is provided in the central portion of the side plate portion 52 . A central portion of the mounting hole 53 is thickened. The function of the mounting holes 53 will be described later.

The interval between the front and rear side plate portions 52 is substantially the same as the dimension of the stator 20 in the front-rear direction. The dimension from the left end of the left support plate portion 55 to the right end of the right support plate portion 55 is substantially the same as the lateral dimension of the stator 20 .

The fastener 50 is manufactured by bending a stainless spring steel plate cut into a predetermined shape, or a metal plate for a leaf spring such as a beryllium copper plate. The fastener 50 may be made of resin.

8 to 12 are explanatory diagrams explaining the assembly process of the actuator 10. FIG. 8 to 12 are cross-sectional views of the central portion along the longitudinal direction of the actuator 10. FIG. The actuator 10 is manufactured by assembling the stator 20, the mover 40 and the fastener 50 in the following procedure.

First, as explained using FIGS. 3 to 5, the stator shaft portion 231 of the stator roller 23 is inserted into the roller support portion 25 of the stator frame 21 to assemble the stator 20 .

As described with reference to FIG. 6, the mover shaft portion 421 of the mover roller 42 is inserted into the roller holding groove 45 of the mover frame 41 to assemble the mover 40 . At this time, by pressing the mover shaft portion 421 against the inlet portion of the roller holding groove 45 from the outside, the roller holding groove 45 is elastically deformed, widening the distance between the opposing stoppers, and moving the mover shaft portion 421 to the roller. It goes into the holding groove 45 . The roller holding groove 45 is elastically restored, and even when the top plate portion 47 is turned upward, the movable roller 42 does not drop.

As shown in FIG. 8, wires 31 are arranged above the stator rollers 23 . The wire 31 has a diameter of just under 0.1 mm. The wire 31 can be inserted through the first wire passage groove 46 described above. The wire 31 is made of shape memory alloy. The wire 31 instantly shortens by about 4% to 5% when the temperature exceeds the transformation point, and returns to its original length when cooled. The transformation point of the wire 31 used in this embodiment is about 70°C to 100°C.

As shown in FIG. 9, the mover 40 is aligned so that the mover roller 42 faces the gap between the stator rollers 23 . At this time, the position of the first wire passage groove 46 and the position of the wire 31 are arranged so as to coincide with each other in the front-rear direction.

As shown in FIG. 10 , the stator 20 and the mover 40 are brought closer together, and the mover roller 42 and the mover frame 41 are inserted into the stator frame 21 . As shown in FIG. 2, the inner surfaces of the front wall and the rear wall of the stator frame 21 are recessed between the roller support portions 25 so that the roller holding portions 44 can be inserted therein.

The wire 31 is drawn into the stator frame 21 by the rotation of the stator roller 23 and the mover roller 42, and forms a wavy shape passing above the stator roller 23 and below the mover roller 42. Become. The wire 31 passes through the first wire passage groove 46 between the stator roller 23 and the mover roller 42 . The function of the first wire passage groove 46 will be described later.

Due to the actions of the stator rollers 23 and the mover rollers 42, it is possible to prevent troubles such as breakage of the wire 31 during assembly due to excessive tensile stress generated in a portion of the wire 31. FIG. As a result, the assembly of the stator 20 and the mover 40 can be performed at high speed and with a high yield.

It should be noted that the state of the wire 31 and the lower side of the slider roller 42 can be confirmed from the lower surface side of the stator frame 21 . A camera may be arranged on the lower surface of the stator frame 21 to detect the presence or absence of an abnormality such as deviation of the wire 31 by image processing in real time.

As shown in FIGS. 11 and 12, the wire 31 is sandwiched between the terminal plate portion 223 and the second terminal plate 32 and fixed by caulking. 13 is an enlarged view of part A in FIG. 11. FIG. 14 is an enlarged view of the B portion of FIG. 12. FIG. Crimping and fixing will be described with reference to FIGS. 2 and 11 to 14. FIG.

As shown in FIG. 2, the second terminal plate 32 is a substantially T-shaped plate. The second terminal plate 32 has a wire holding groove 33 on the lower surface of the portion corresponding to the T-shaped vertical bar as indicated by the dashed line. The wire holding groove 33 is a U-shaped groove having substantially the same width and depth as the outer shape of the wire 31 . The second terminal plate 32 is made of a highly conductive metal such as brass or phosphor bronze.

The second terminal plate 32 is arranged on the terminal plate portion 223 so that the wire 31 is inserted into the wire holding groove 33 . The terminal plate portion 223, the wire 31, and the second terminal plate 32 are caulked and fixed by supporting the lower surface of the terminal plate portion 223 with a die and pushing a punch from the upper side of the second terminal plate 32 into a position corresponding to the terminal recess 221. Then, the crimped portion 35 is created.

By using a punch having a groove in the portion corresponding to the wire 31, the crimped portion 35 has a streak-like shape raised above the wire 31 as shown in FIG. As shown in FIG. 14, the wire 31 can be prevented from breaking by plastically deforming the terminal plate portion 223 and the second terminal plate 32 without crushing the wire 31 too much.

At the crimped portion 35, the wire 31, the fixed terminal 22, and the second terminal plate 32 are electrically and mechanically joined. As described above, the wire 31 and the fixed terminal 22 can be properly connected. After that, the excess wire 31 is cut and removed outside the fixed terminal 22 . Both ends of the wire 31 are connected to the fixed terminals 22 respectively.

Next, the fastener 50 is put on the slider 40 from above, and the attachment hole 53 and the fastener fixing projection 24 are engaged. A more detailed description will be given. As shown in FIG. 3, the upper surface of the fastener fixing projection 24 is slanted outward. A lower end portion of the fastener 50 extends along the upper surface of the fastener fixing projection 24 . As described above, since the attachment hole 53 is elongated, elastic deformation allows the fastener fixing projection 24 to pass therethrough. After the fastener fixing protrusion 24 has passed through, the fastener 50 is elastically restored. As a result, the fastener fixing projection 24 and the mounting hole 53 are engaged as shown in FIG.

The biasing spring 51 presses the mover 40 against the stator 20 . As described above, a total of four urging springs 51 are provided on the left and right sides of the connecting portion 54 , so that the front, rear, left, and right sides of the mover 40 are evenly pressed toward the stator 20 . As shown in FIG. 1, the pressing portions 43 protrude upward from between the left and right urging springs 51, respectively. By the above, the actuator 10 shown in FIG. 1 is completed.

FIG. 15 is a top view of the actuator 10. FIG. 16 is a cross-sectional view along line XVI-XVI of FIG. 15. FIG. 17 is a cross-sectional view taken along line XVII-XVII of FIG. 15. FIG. 18 is a cross-sectional view taken along line XVIII-XVIII of FIG. 15. FIG. 19 is a cross-sectional view along line XIX-XIX of FIG. 15. FIG. The structure of the actuator 10 after completion will be described using FIGS. 1 and 15 to 19. FIG.

As shown in FIGS. 1, 16 and 19, the upper surface of the fastener support portion 26 and the lower surface of the support plate portion 55 abut to fix the fastener 50 on the stator frame 21 . As shown in FIGS. 17 and 18 , the biasing spring 51 biases the top plate portion 47 toward the stator 20 .

As shown in FIGS. 16 and 18 , a space is provided between the lower surface of the connecting portion 54 and the upper surface of the top plate portion 47 . The function of this space will be described later.

As shown in FIG. 16, five stator rollers 23 and four mover rollers 42 are arranged in parallel and alternately. The wire 31 is bent to weave between the upper portion of the stator roller 23 and the lower portion of the slider roller 42 . The lower ends of the fixed terminals 22 connected to both ends of the wires 31 protrude below the lower surface of the stator frame 21 .

As shown in FIG. 19, the wire 31 is crimped and fixed between the upper surface of the terminal plate portion 223 of the fixed terminal 22 and the second terminal plate 32 . As described above, crimping is performed while the wire 31 is held in the wire holding groove 33 provided in the second terminal plate 32, so that the cross-sectional shape of the wire 31 at the crimped portion 35 maintains a substantially circular shape.

As long as the fixed terminal 22 and the second terminal plate 32 can be crimped and fixed without breaking the wire 31, the cross-sectional shape of the wire 31 after crimping is arbitrary. It may be rectangular or the like.

The actuator 10 is used while being sandwiched from above and below by a first plate 61 and a second plate 62 shown in phantom lines in FIGS. 16 and 17 . The first plate 61 is, for example, a printed circuit board, and has holes into which the tips of the fixed terminals 22 can be inserted. The fixed terminal 22 is connected to an electric circuit provided on the printed circuit board by soldering.

The second plate 62 is, for example, a glass substrate on the surface of a touch panel, which is touched by a user who uses the device to which the actuator 10 is attached, or a part in the vicinity thereof.

20A and 20B are explanatory diagrams for explaining the operation state of the actuator 10. FIG. The operation of the actuator 10 will be described using FIGS. 16 and 20. FIG.

16 shows the initial state of the actuator 10. FIG. By applying a pulse voltage between the fixed terminals 22, the wire 31 instantly generates heat due to Joule heat. The wire 31 instantly shortens when the temperature exceeds the transformation point. The shortening of the wire 31 causes the slider roller 42 to move upward. As the mover roller 42 moves, the mover 40 pushes the urging spring 51 and moves upward.

The space between the lower surface of the connecting portion 54 and the upper surface of the top plate portion 47 in FIGS. 16 and 18 is a space in which the upper surface of the top plate portion 47 can move when the mover 40 is operated. . This space has a height such that the connecting portion 54 and the top plate portion 47 do not collide when a predetermined pulse voltage is applied between the left and right fixed terminals 22 .

When the pulse voltage ends, the generation of Joule heat stops. The heat generated in the wire 31 is dissipated outside through the stator rollers 23 and the slider rollers 42, and the temperature of the wire 31 drops below the transformation point. The action of the biasing spring 51 restores the length of the wire 31 and the actuator 10 returns to the state described using FIG.

Since the heat capacity of the wire 31 is much smaller than the heat capacity of the entire actuator 10, the temperature of the entire actuator 10 hardly rises even when the pulse voltage is repeatedly applied and operated. In addition, when the actuator 10 is operated frequently, a cooling mechanism such as a Peltier device or a radiator plate may be attached to the actuator 10 .

As described above, the application of the pulse voltage momentarily increases the distance between the first plate 61 and the second plate 62, and then returns to the original state. Thereby, the user touching the second plate 62 feels a click feeling.

Due to the action of the urging spring 51, the height of the mover 40 returns to its original height each time the movement is completed. As a result, it is possible to realize the mover 40 that repeats the operation of moving by a constant amount from a constant starting position every time the pulse voltage is applied. Thereby, the actuator 10 having stable characteristics can be realized.

The first wire passage groove 46 prevents the wire 31 from meandering and falling off from the mover roller 42 and the stator roller 23 . The state of the wire 31 is stably maintained by the first wire passage groove 46 . This makes it possible to realize the actuator 10 that operates stably.

When the stretched state of the wire 31 varies depending on the location, the tension applied to the wire 31 is kept uniform by automatically rotating the stator roller 23 and the mover roller 42 . Therefore, even when a thin wire 31 is used, breakage of the wire 31 can be prevented.

When thin wires 31 are used, the resistance of the wires 31 increases. Therefore, when Joule heat is generated by constant-voltage pulse driving, the current value flowing through the wire 31 is reduced. As described above, the actuator 10 with low current consumption can be provided.

Furthermore, when thin wires 31 are used, the heat capacity of the wires 31 is reduced. Therefore, Joule heat generated by pulse driving is quickly dissipated. As described above, the actuator 10 with quick response can be provided. Also, since less Joule heat is generated in the wire 31, the actuator 10 can be provided with less temperature rise even when used repeatedly.

The stator rollers 23 and the mover rollers 42 are supported by the insulating stator frame 21 and the mover frame 41, respectively, and are insulated from each other. Therefore, even if a material having both high thermal conductivity and high electrical conductivity such as copper is used for the stator rollers 23 and the mover rollers 42, application of the pulse voltage to both ends of the wire 31 is not prevented.

FIG. 21 is an enlarged view of part C in FIG. Details of the widths of the roller support portions 25 and the roller holding grooves 45 will be described with reference to FIG.

The diameter of the stator shaft portion 231 is D1, the diameter of the mover shaft portion 421 is D2, the width of the roller support portion 25 is P, and the width of the roller holding groove 45 is Q, respectively. In the present embodiment, D1=D2=0.5 mm, and the diameter of the central portion of stator roller 23 and slider roller 42 is 1 mm. The sum p of the gaps between the left and right roller support portions 25 of one stator shaft portion 231 is expressed by Equation (1).
p = P-D1 (1)

Similarly, the sum q of the gaps between the left and right roller holding grooves 45 of one mover shaft portion 421 is expressed by Equation (2).
q=Q−D2 (2)

When the stator frame 21 and the mover frame 41 are made of resin, and the stator rollers 23 and the mover rollers 42 are made of metal, p ranges from about 0.04 mm to 0.1 mm, and q is It is desirable to be about 0.04 to 0.06 millimeters greater than p. More preferably, p is on the order of 0.07 millimeters and q is on the order of 0.12 millimeters.

In this way, the stator rollers 23 and the slider rollers 42 can be rotated smoothly by sizing the portions supporting the stator shaft portion 231 and the slider shaft portion 421 with a so-called backlash. , the actuator 10 that prevents the wire 31 from breaking can be realized.

FIG. 22 is an explanatory diagram illustrating a state in which the mover 40 is shifted to the left. In FIG. 22, illustration of the fastener 50 is omitted. The second plate 62 is moving to the left. Being dragged by the second plate 62, the mover 40 also moves to the left and deviates from its original position.

Such deviation can occur, for example, when an external force in the shear direction is applied between the first plate 61 and the second plate 62 . It can also occur when an external force such as a pressing force is applied between the first plate 61 and the second plate 62 outside the location where the actuator 10 is fixed.

When the mover 40 shifts from its original position, the tension applied to the wire 31 on the left and right sides of the mover roller 42 is unbalanced. Specifically, tension is applied to the wire 31 at the portion E indicated by the ellipse, ie, the right side of the slider roller 42 . On the other hand, the wire 31 is loosened at the F portion indicated by the ellipse, ie, the left side of the slider roller 42 .

If the deviation is slight, the stator shaft portion 231 moves to the left and the mover shaft portion 421 moves to the right in the roller support portion 25 and the roller holding groove 45, thereby relaxing the tension applied to the wire 31. and equalize. Therefore, breakage of the wire 31 is prevented.

Even if the deviation is large, the stator roller 23 and the mover roller 42 rotate, and the wire 31 is drawn from the left side to the right side of the stator roller 23, thereby easing the tension applied to the wire 31. be in an even state. Therefore, breakage of the wire 31 is prevented. Since the roller is rotatable, breakage of the wire 31 due to friction between the wire 31 and the roller is also prevented.

As described above, it is possible to provide the actuator 10 that can prevent the wire 31 from breaking even when various external forces are applied.

By setting the value of p as described with reference to FIG. 21, it is possible to limit the amount of movement of the stator roller 23 in the left-right direction and prevent abnormal deformation such as bending of the wire 31 from occurring. . By making the value of q larger than the value of p, the mover roller 42 moves quickly following the inclination and deviation of the mover 40, and breakage of the wire 31 can be prevented.

That is, by supporting the stator rollers 23 with play in the arrangement direction and by supporting the mover rollers 42 with greater play in the same direction, each of the wires 31 is automatically extended and contracted. Roller moves. This makes it possible to provide the actuator 10 that automatically keeps the tension generated in the wire 31 uniform.

Since the fixed terminal 22 and the stator roller 23 are arranged adjacent to each other, the wire 31 near the fixed terminal 22 does not move vertically even when the moving element 40 moves vertically. Since no force is applied to the wire 31 in the shearing direction, the actuator 10 that can prevent the wire 31 from breaking can be provided.

As described above, it is desirable that the height of the upper surfaces of the left and right terminal plate portions 223 and the height of the upper ends of the five stator rollers 23 are substantially the same. By doing so, as shown in FIG. 16, the wire 31 is not bent between the left and right crimped portions 35 and the stator rollers 23 at both ends, and becomes substantially straight. Therefore, it is possible to prevent unnecessary stress from being applied to the wire 31 near the crimped portion 35 . In addition, it is possible to prevent the wire 31 from being damaged by rubbing against the edge of the second terminal plate 32 or the like.

The shape and material of the mover roller 42 may be different from those of the stator roller 23 , but it is desirable that they have the same shape and material as the stator roller 23 from the viewpoint of obtaining uniform heat radiation from the wire 31 . By using common parts for the stator rollers 23 and the mover rollers 42, the cost of the actuator 10 and labor for parts management can also be reduced.

A case where the actuator 10 is attached to a touch panel and used will be described. By operating the actuator 10 in accordance with the user's operation of the touch panel to move the surface of the touch panel, the user can feel as if he were operating a mechanical keyboard.

A device to which the actuator 10 is attached is not limited to a touch panel type information device such as a smart phone or a tablet. The actuator 10 may be attached to a steering wheel, seat, or the like of transportation equipment such as automobiles, motorcycles, or bicycles. In addition, the actuator 10 can be attached to any device that a user touches and uses.

By operating the actuator 10 according to the operation performed by the user, it is possible to provide feedback on the operation through the sense of touch. In addition, for example, when an abnormality occurs during automatic operation, by operating the actuator 10, the user's attention can be called through the sense of touch.

The pressing portion 43 can have any shape according to the portion where the actuator 10 is attached. For example, the pressing portion 43 may have a hole for inserting a pin from above or a screw hole for fixing a screw. The pressing portion 43 may have the shape of a protrusion or a depression that engages with the portion where the actuator 10 is attached.

According to this embodiment, the actuator 10 with low power consumption can be provided. According to this embodiment, it is possible to provide the actuator 10 that is small and that generates displacement instantaneously. Actuator 10 of the present embodiment is suitable for a so-called tactile device that presents a user with a tactile sensation such as a click sensation.

According to this embodiment, the actuator 10 can be easily assembled. Specifically, it is possible to provide the actuator 10 in which the stator 20 and the mover 40 are easily assembled. Further, the actuator 10 can be provided in which the stator 20, the wire 31 and the mover 40 can be easily assembled. According to this embodiment, breakage of the wire 31 during assembly can be prevented.

By observing the state of the wires 31 from the bottom surface of the stator 20 when assembling the stator 20 and the mover 40, it is possible to quickly detect the occurrence of troubles in the assembly process and provide the actuator 10 capable of countermeasures.

Since the stator roller 23 and the mover roller 42 are held by the stator shaft portion 231 and the mover shaft portion 421, which are small diameter portions, respectively, the stator roller 23 and the mover roller 42 are arranged as shown in FIG. Can be placed close to each other in the left and right direction. Therefore, a compact actuator 10 can be realized.

Further, the rotational moment applied to the stator rollers 23 and the mover rollers 42 due to the expansion and contraction of the wire 31 easily exceeds the rotational moment due to the frictional force generated in the stator shaft portion 231 and the mover shaft portion 421 . As a result, the stator roller 23 and the mover roller 42 rotate smoothly in conjunction with the expansion and contraction of the wire 31 .

Here, the rotational moment applied to the stator roller 23 and the mover roller 42 is the product of the force of the wire 31 rotating the stator roller 23 and the mover roller 42 and the radius of the stator roller 23 and the mover roller 42. is. The rotational moment due to the frictional force is the product of the frictional force generated between the stator shaft portion 231 and the mover shaft portion 421 and the portion that supports them, and the radius of the stator shaft portion 231 and the mover shaft portion 421. be.

The surfaces of the stator roller 23 and the mover roller 42 may be covered with a film made of a highly lubricating material. The thickness of the film is a thickness that does not interfere with heat transfer between the wire 31 and the stator rollers 23 and the slider rollers 42 . Specifically, the thickness of the coating is about 1 micrometer to several tens of micrometers.

By reducing the friction between the stator shaft portion 231 and the roller support portion 25 and the friction between the slider shaft portion 421 and the roller holding groove 45, the stator roller 23 and the slider roller 42 are reduced. It can rotate smoothly. Furthermore, the wire 31 can be expanded and contracted smoothly by reducing the friction between the wire 31 and the stator roller 23 and the mover roller 42 . As described above, breakage of the wire 31 can be prevented.

The highly lubricious material described above may be insulating. If the surfaces of stator shaft portion 231 and mover shaft portion 421 are covered with an insulating material, stator frame 21 and mover frame 41 may be made of a conductive material.

The lower surface of the stator frame 21 may be previously covered with a transparent plate or the like. After assembling the stator 20 and the mover 40, the lower surface of the stator 20 may be covered with a plate or the like. Damage due to entry of foreign matter into the actuator 10 can be prevented without interfering with observation from the lower surface of the stator 20 in the assembly process. If the assembly process is stable and there is little need to observe the assembly process of the stator 20 and the mover 40, the stator frame 21 may be bottomed and opaque.

According to this embodiment, it is possible to provide the actuator 10 that prevents the wire 31 from breaking when an external force is applied. According to this embodiment, it is possible to provide the actuator 10 that can be easily mounted on a printed circuit board or the like.

The actuator 10 does not need to be provided with the biasing spring 51 when it is used in an application having a means for biasing the first plate 61 and the second plate 62 in the direction of pressing them against each other. Furthermore, the actuator 10 does not have to be provided with the fastener 50 .

The numbers of stator rollers 23 and slider rollers 42 are not limited to five and four. Actuator 10 may have any number of stator rollers 23 and slider rollers 42 . The number of wires 31 is not limited to one. Actuator 10 may have any number of wires 31 . The dimensions of each part of the actuator 10 are not limited to those described in this embodiment.

The actuator 10 may be used with the stator 20 side fixed near a portion touched by the user.

[Embodiment 2]
The present embodiment relates to an actuator 10 suitable for applications in which the mover 40 is less likely to shift laterally. Descriptions of parts common to the first embodiment are omitted.

FIG. 23 is an exploded perspective view of actuator 10 of the second embodiment. FIG. 24 is a cross-sectional view of actuator 10 of the second embodiment. The stator 20 has five stator protrusions 29 integrally formed with the stator frame 21 . The upper surface of the stator protrusion 29 is a substantially cylindrical surface. The mover 40 has four mover protrusions 49 integrally formed with the top plate portion 47 . The lower surface of the mover projection 49 is a substantially cylindrical surface.

The stator 20 and the mover 40 are desirably manufactured by injection molding of resin. More preferably, the surfaces of the stator protrusions 29 and the slider protrusions 49 are covered with a film made of a material with good lubricity.

The stator 20 and mover 40 may be made of ceramics or metal. The stator 20 and mover 40 may be made of different materials. When the stator 20 and the mover 40 are made of a conductive material, the surfaces of the stator protrusions 29 and the mover protrusions 49 are covered with a film made of an insulating material.

The second terminal plate 32 has a shallow depression in the central portion in addition to the wire holding groove 33 . When the fixed terminal 22, the wire 31, and the second terminal plate 32 are crimped and fixed, the punch can be positioned using this depression as a mark.

When the actuator 10 of the present embodiment is used, as indicated by a two-dot chain line in FIG. It is desirable to provide a configuration such as 63. By preventing lateral displacement of the mover 40, breakage of the wire 31 during use can be prevented.

[Embodiment 3]
This embodiment relates to an actuator 10 in which a curved surface portion 27 is provided on the edge of a fixed terminal 22. As shown in FIG. Descriptions of parts common to the first embodiment are omitted. FIG. 25 is a perspective view of the stator 20 of Embodiment 3. FIG. FIG. 26 is a cross-sectional view of actuator 10 of the third embodiment.

The fixed terminal 22 has a curved surface portion 27 extending in the same direction as the terminal leg portion 222 from the side of the terminal plate portion 223 farther from the terminal leg portion 222 . The curved surface portion 27 has substantially the same curvature as the curvature of the stator roller 23 . The stator 20 has three stator rollers 23 .

As shown in FIG. 2, both ends of the wire 31 are bent along the curved surface portion 27 and come into contact with the slider roller 42 . Since Joule heat is not generated in the wire 31 at the portion in contact with the fixed terminal 22 which is a conductor, no shrinkage occurs.

Even if the surface of the fixed terminal 22 or the wire 31 is provided with a non-conductive coating, the Joule heat generated in the wire 31 quickly diffuses to the fixed terminal 22, so the temperature of the wire 31 does not rise. Therefore, the wire 31 does not shrink at the portion in contact with the fixed terminal 22 .

Unlike the first embodiment, there is no portion where the wire 31 is held in the horizontal direction between the terminal plate portion 223 and the stator roller 23 (see FIG. 14). Therefore, it is possible to provide the actuator 10 in which the expansion and contraction of the wire 31 when the pulse voltage is applied efficiently contributes to the movement of the mover 40 in the front-rear direction.

[Embodiment 4]
This embodiment relates to an actuator 10 in which a stator 20 has grooves that prevent wires 31 from slipping. Descriptions of parts common to the first embodiment are omitted. FIG. 27 is a perspective view of the stator 20 of Embodiment 4. FIG. FIG. 28 is a cross-sectional view of stator 20 of the fourth embodiment.

The stator frame 21 is a substantially rectangular frame elongated in the left-right direction, and has five pairs of roller support portions 25 on the inner surfaces of the front and rear walls. The roller support portions 25 are substantially U-shaped grooves that open upward, and are opposed to each other in pairs. The width of the opening of the roller support portion 25 is slightly wider than the diameter of the stator shaft portion 231 . One stator roller 23 is rotatably supported by a pair of opposing roller support portions 25 .

The front wall and the rear wall of the stator frame 21 are connected via a substantially U-shaped connecting portion 28 that opens upward. Connections 28 surround the left, right and bottom of stator rollers 23 . The connecting portion 28 prevents deformation such that the stator frame 21 expands in the front-rear direction.

A second wire passage groove 212 is provided on each of the left and right walls of the connecting portion 28 to divide the connecting portion 28 into front and rear. The second wire passage groove 212 has a groove width larger than the outer shape of the wire 31 .

FIG. 29 is a perspective view of the mover 40 of Embodiment 4. FIG. The mover 40 has a mover frame 41 and four mover rollers 42 .

The slider frame 41 has a top plate portion 47 and four rectangular box-shaped roller holding portions 44 . The top plate portion 47 has a substantially rectangular plate shape with substantially the same dimensions as the stator frame 21 in the front-rear direction and shorter than the stator frame 21 in the left-right direction. The roller holding portions 44 are arranged in a line in the left-right direction on the lower surface of the top plate portion 47 with the openings facing downward. The right and left walls of the roller holding portion 44 are wide open.

Roller holding grooves 45 are provided in the front wall and the rear wall of the slider frame 41 . One movable roller 42 is rotatably held inside the roller holding portion 44 by a pair of opposing roller holding grooves 45 . The mover roller 42 does not fall off even when the mover 40 is held with the top plate portion 47 facing upward, due to the retaining action provided at the inlet portion of the roller holding groove 45 .

The actuator 10 is completed by assembling the stator 20 described using FIGS. 27 and 28 and the mover 40 described using FIG.

The wire 31 is corrugated through the upper side of the stator roller 23 and the lower side of the slider roller 42 . The wire 31 passes through the second wire passage groove 212 between the stator roller 23 and the mover roller 42 .

According to this embodiment, since the mover 40 is lightweight, it is possible to provide the actuator 10 with low power consumption.

[Embodiment 5]
This embodiment relates to an actuator 10 having rollers with grooves for guiding wires 31 . Descriptions of parts common to the first embodiment are omitted. FIG. 30 is a front view of the stator roller 23 of Embodiment 5. FIG. The movable roller 42 also has the same shape.

The stator rollers 23 are cylindrical. The stator roller 23 has a cylindrical stator shaft portion 231 coaxially protruding from both end faces. The stator roller 23 has two ridges 232 on its side surface. The ridge portion 232 is a strip-like projection that makes one turn around the central axis of the stator roller 23 . The two ridges 232 are parallel and a guide groove 233 is formed therebetween.

When the stator roller 23 is viewed in a cross section taken along a plane including the central axis, the guide groove 233 has an arcuate bottom with a radius approximately 10 percent larger than the radius of the wire 31 .

FIG. 31 is a cross-sectional view of actuator 10 of Embodiment 5. FIG. Since the wire 31 is guided by the guide groove 233, it is prevented from slipping in the front-rear direction. Since the bottom of the guide groove 233 and the outline of the wire 31 are close to each other, the heat generated by the wire 31 is easily conducted to the stator rollers 23 and the mover rollers 42 . Therefore, the wire 31 is quickly cooled after applying the pulse.

Either one of the stator roller 23 and the mover roller 42 may have the shape described with reference to FIG. Some of the plurality of stator rollers 23 and slider rollers 42 may be shaped as described using FIG.

[Embodiment 6]
This embodiment relates to an actuator 10 in which stator rollers 23 on both ends and adjacent fixed terminals 22 are electrically connected. Descriptions of parts common to the first embodiment are omitted.

FIG. 32 is an exploded perspective view of actuator 10 of Embodiment 6. FIG. The stator 20 has a stator frame 21 , fixed terminals 22 and five stator rollers 23 . Of the five stator rollers 23, one stator roller 23 on each side arranged adjacent to the fixed terminal 22 is an end stator roller 234 having a different shape from the other stator rollers 23. .

The end stator rollers 234 are cylindrical with the same outer diameter as the stator rollers 23 and lower than the stator rollers 23 . The end stator rollers 234 have cylindrical end stator shafts 235 coaxially protruding from both end faces. The height of the end stator rollers 234 including the end stator shafts 235 is the same as the height of the stator rollers 23 including the stator shafts 231 .

The end stator rollers 234 are made of a material that has both high thermal conductivity and electrical conductivity. The material of the end stator rollers 234 is preferably copper. When aluminum is used as the material of the end stator rollers 234, a highly conductive film such as copper plating is formed on the surface. This is because aluminum tends to form a non-conductive oxide film on its surface.

The second terminal plate 32 is a substantially T-shaped plate. The second terminal plate 32 has a bifurcated brush portion 36 at the tip of the portion corresponding to the T-shaped vertical bar. The brush portion 36 is bent obliquely downward. The second terminal plate 32 is made of a highly conductive metal such as brass or phosphor bronze.

FIG. 33 is a perspective view of actuator 10 from which fastener 50 and mover 40 are removed according to the sixth embodiment. FIG. 34 is a partially enlarged cross-sectional view of actuator 10 from which fastener 50 and mover 40 of Embodiment 6 are removed.

The brush portion 36 is pressed against the end stator shaft portion 235 . Therefore, the end stator roller 234 is rotatable, and electrically connected to the fixed terminal 22 via the brush portion 36 , the second terminal plate 32 and the crimped portion 35 . That is, the brush portion 36 and the end stator rollers 234 form a so-called slip ring-like structure.

According to this embodiment, no current flows through the wires 31 between the fixed terminals 22 and the end stator rollers 234 . A pulse voltage is applied between the end stator rollers 234 at both ends. Since the pulse voltage is applied only to the portion of the wire 31 that contributes to the operation of the moving element 40, the actuator 10 with high efficiency and low power consumption can be provided.

The technical features (constituent elements) described in each embodiment can be combined with each other, and new technical features can be formed by combining them.
The embodiments disclosed this time are illustrative in all respects and should be considered not restrictive. The scope of the present invention is indicated by the scope of the claims rather than the meaning described above, and is intended to include all modifications within the scope and meaning equivalent to the scope of the claims.

REFERENCE SIGNS LIST 10 actuator 20 stator 21 stator frame 212 second wire passage groove 22 fixed terminal 221 terminal recess 222 terminal leg 223 terminal plate 23 stator roller 231 stator shaft 232 ridge 233 guide groove 234 end stator roller 235 end stator shaft portion 24 fastener fixing projection 25 roller support portion 26 fastener support portion 27 curved surface portion 28 connection portion 29 stator projection 31 wire 32 second terminal plate (terminal plate)
33 Wire holding groove 35 Crimping part 36 Brush part 40 Slider 41 Slider frame 42 Slider roller 421 Slider shaft part 43 Pressing part 44 Roller holding part 45 Roller holding groove 46 First wire passing groove 47 Top plate part 49 Slider Projection 50 Fastener 51 Biasing spring 52 Side plate portion 53 Mounting hole 54 Connecting portion 55 Support plate portion 61 First plate 62 Second plate 63 Sliding column

Claims (12)

a stator having a plurality of rotatably supported stator rollers and fixed terminals respectively arranged on both sides in the arrangement direction of the stator rollers;
a mover having a mover roller disposed between the stator rollers and rotatably supported;
a shape memory alloy wire sandwiched between the stator roller and the mover roller;
A terminal plate in which both ends of the wire are crimped and fixed to the fixed terminal,
The terminal plate has a shape in which depressions are formed on both sides of a portion corresponding to the wire in the crimped portion, and the portion corresponding to the wire is relatively swollen in a streaky shape parallel to the wire , and The portion corresponding to the wire is recessed with respect to the surface of the terminal board.
actuator. 2. The actuator according to claim 1, wherein the terminal plate has depressions on both sides of a portion corresponding to the wire in the crimped portion. 3. The actuator according to claim 1, wherein the terminal plate includes wire holding grooves corresponding to the wires. two side plate portions attached to the stator; a connecting portion connecting the side plate portions to the stator with the slider interposed therebetween; 4. An actuator according to any one of claims 1 to 3, comprising a clasp comprising a biasing spring biasing towards the stator. 5. The actuator according to claim 4, wherein the urging spring is a plate spring extending from the connecting portion in the arrangement direction of the stator rollers and urging the mover toward the stator at the tip side thereof. 6. The stator roller according to any one of claims 1 to 5, wherein the stator roller has a stepped cylindrical shape having stator shaft portions at both ends that are narrower than the central portion, and is supported by the stator shaft portions. Actuator as described. 7. The moving roller according to any one of claims 1 to 6, wherein the moving roller has a stepped cylindrical shape having moving shafts at both ends that are narrower than the central portion, and is supported by the moving shafts. Actuator as described. The actuator according to any one of claims 1 to 7, wherein the stator roller has the same shape as the slider roller. Attaching a plurality of stator rollers to a stator having fixed terminals respectively arranged on both sides in the arrangement direction of the stator rollers;
A slider roller is rotatably attached to the slider,
A wire made of a shape memory alloy is sandwiched between the stator roller and the slider roller,
inserting the mover roller between the stator rollers;
sandwiching both ends of the shape memory alloy wire between the fixed terminal and the terminal plate;
The terminal plate and the fixed terminal are crimped and fixed using a punch having a groove corresponding to the wire, and the terminal plate is crimped so that depressions are formed on both sides of the portion corresponding to the wire in the crimped portion. a portion corresponding to the wire has a relatively raised shape in a streak-like shape parallel to the wire, and a portion corresponding to the wire is formed in a shape recessed with respect to the surface of the terminal plate
A method for manufacturing an actuator. 10. The method of manufacturing an actuator according to claim 9, wherein the terminal plate has wire holding grooves corresponding to the wires. 11. The method of manufacturing an actuator according to claim 9, wherein the fixed terminal has a recess corresponding to a position to be crimped and fixed. a fastener having two side plate portions, a connection portion connecting the side plate portions, and a biasing spring extending from the connection portion, sandwiching the slider between the connection portion and the stator; 12. The actuator according to any one of claims 9 to 11, wherein the two side plate portions are respectively attached to the stator while the biasing spring biases the mover toward the stator. manufacturing method.

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