JPH0241353Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an actuator that uses a shape memory alloy and can also be used as a holding device for a robot or the like.

[Conventional technology]

Conventionally, in an actuator using a shape memory alloy, a method for controlling heating and cooling of the shape memory alloy in order to produce a shape memory effect is to blow hot air and cold air onto the shape memory alloy.

A current is applied to generate heat due to the resistance of the shape memory alloy itself.

etc.

However, both methods use thin wires or small pieces of shape memory alloy to facilitate heating and cooling, making the actuator structure complex and complicated to control. There was a drawback that it could not produce any effect.

[Problem that the invention seeks to solve]

SUMMARY OF THE INVENTION An object of the present invention is to provide an actuator that can easily and efficiently perform heating and cooling control to produce a shape memory effect with a simple configuration.

[Means for solving problems]

An actuator using a leaf spring made of a shape memory alloy, the actuator comprising: an electric means for heating the leaf spring; a means for supporting one end of the leaf spring; and one end of the leaf spring supported and the other end being movable. and a means for holding an object disposed in the plate spring, and the plate spring is characterized in that a predetermined groove is provided in order to increase the electrical resistance value.

〔Example〕

The present invention will be explained below based on examples. FIG. 1 is an explanatory diagram of an embodiment of the present invention, and FIG. 2 is a detailed diagram of a shape memory alloy leaf spring according to the embodiment of FIG. 1, and an explanatory diagram of a circuit for heating the leaf spring.

In the figure, numerals 1 and 2 are plate springs made of a bidirectional shape memory alloy, and the plate springs 1 and 2 are formed into plate shapes with a desired shape memorized in advance.

Hands 3 and 4 are holding means for holding the object 15, and one end of the hands 3 and 4 is fixed by leaf springs 1 and 2 and a support plate 5. The other ends of the leaf springs 1 and 2 are fixed to the hand base 7 by a mounting plate 6. The hand base 7 is fixed to the arm 8. One ends of hands 3 and 4 are movably arranged, and one end of hands 3 and 4 is arranged movably.
The hand 4 and the hand 4 are arranged to face each other with a predetermined distance from each other by the hand base 7. Since the hands 3 and 4 are integrated with the leaf springs 1 and 2 by the support plate 5 at one end, the hands 3 and 4 are moved by the movement of the leaf springs 1 and 2. This allows the hands 3 and 4 to hold the object 15. In addition, receiving plates 31 and 41 having a horizontal surface on the inside are provided at required portions of the lower ends of the hand bases 3 and 4, and one end of the movable side is provided with receiving plates 32 and 42 bent inward.
A receiving plate portion is provided so that the object 15 can be easily held.

It is assumed that the arm 8 is attached to the main body of a device such as a robot (not shown). The leaf springs 1 and 2 are shaped so that when heated to a high temperature, they curve outward in the direction shown by the arrow in FIG. 1, and when cooled, they return to the inner direction. shall be. 9 is a controller that applies current to heat the leaf springs 1 and 2;
Connect to connection terminals 10 and 11 provided on leaf springs 1 and 2. As shown in FIG. 2, the leaf springs 1 and 2 are provided with grooves 21 of a predetermined width at required locations. The electric resistance value of the leaf springs 1 and 2 is increased by making the circuit longer. Therefore, leaf springs 1 and 2
In this case, the electrical resistance value increases compared to the case where the groove 21 is not provided.

In this embodiment, when the plate springs 1 and 2 are to be heated to a high temperature, a current is applied to the plate springs 1 and 2 through the cable 12 by the controller 9. As mentioned above, since the leaf springs 1 and 2 have their own circuit resistance increased, the leaf springs 1 and 2 are efficiently heated and reach a high temperature, and the hands 3 and 4 are
It is moved in the direction of the arrow shown in the figure. When the leaf springs 1 and 2 are cooled in this embodiment, since the leaf springs 1 and 2 are plate-shaped and have a large surface area, cooling is performed naturally. Note that the time required for cooling can be shortened by blowing air onto the leaf springs 1 and 2 from an air source (not shown). When the leaf springs 1 and 2 are cooled, the leaf springs 1 and 2 will return inward, and the hands 3 and 4 will also return inward.

Next, the operation in this embodiment will be explained. When holding an object 15 loaded on a support stand (not shown), the leaf springs 1 and 2 are heated to a high temperature, the hands 3 and 4 are moved in the direction of the arrow in FIG. is placed in the open state on the support stand loaded with the object 15. Next, when the leaf springs 1 and 2 are cooled, the hands 3 and 4 return inward, that is, one end of the hands 3 and 4 returns to the inside.
The object 15 can be held. When releasing the object 15, the operation described above can be reversed. Therefore, by heating and cooling the leaf springs 1 and 2, the object 15 can be held and dissolved. That is, by alternately heating and cooling the leaf springs 1 and 2, the hands 3 and 4
One end of the actuator can be returned to its original state in the outward direction indicated by the arrow in FIG. 1, allowing the invention to operate as an actuator. Note that grooves 21 are provided to increase the electrical resistance value of the leaf springs 1 and 2.
Of course, the shape of and the location of the groove 21 are not limited to those of this embodiment, and other means for increasing the electrical resistance value may be used.

According to this embodiment, a plate spring using a shape memory alloy has a simple configuration and is heated and cooled to hold an object that can be operated efficiently without affecting the surrounding environment. Actuator can be realized.

In this embodiment, two sets of leaf springs and hands are arranged to oppose each other, but one set of hands is assumed to be fixed and not movable, and the same effect can be achieved even if only one set of hands is movable. It can have the effect of Furthermore, in this example, an example of opening/closing operation using a single sheet of bidirectional shape memory alloy was described;
By combining a unidirectional shape memory alloy with a leaf spring other than a shape memory alloy, it is possible to obtain the shape when cooled by the bias force of the leaf spring during cooling.

[Effect of idea]

According to the present invention, an actuator using a shape memory alloy that can easily and efficiently perform heating and cooling to produce a shape memory effect with a simple configuration, and does not cause pollution or other effects on the surrounding environment. This actuator can also be used as a holding device for objects such as robots.

Therefore, it is an optimal actuator especially in clean rooms where dust generation is averse.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of an embodiment of the present invention, and FIG. 2 is a detailed diagram of the shape memory alloy leaf spring of FIG. 1 and an explanatory diagram of a circuit for heating the leaf spring. 1 and 2 are leaf springs, 3 and 4 are hands, 5 is a support plate, 6 is a mounting plate, 7 is a hand base, 8 is an arm, 9 is a controller, 10 and 11 are terminals, 12
is the cable, and 21 is the groove.

Claims (1)

[Scope of utility model registration request] In an actuator using a leaf spring made of a shape memory alloy, an electric means for heating the leaf spring, a means for supporting one end of the leaf spring, and one end of the leaf spring supported and the other end movably arranged. an actuator using a shape memory alloy, characterized in that the plate spring is provided with a predetermined groove in order to increase the electrical resistance value.