JP2001260093A - Shape recovery control method for shape memory alloy and manipulator using shape memory alloy - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a shape recovery control method for a shape memory alloy capable of restraining the shape recovery of the SMA even if it is heated with a heater and to provide a manipulator using a shape memory alloy capable of restraining the shape recovery of a fixed part of an SMA plate and of being structured only by sticking the SMA plate to the surface of a fixing ring member having a simple shape. SOLUTION: According to one embodiment of this application, the shape recovery control method for the shape memory alloy characterized in restraining the shape recovery in a predetermined region of a base body formed of the shape memory alloy is provided by irradiating an energy beam on the predetermined region where the shape recovery of the base body formed of the shape memory alloy should be restrained so as to heat it. According to another embodiment of the application, the manipulator formed of the shape memory alloy is provided with the shape memory alloy characterized in restraining the shape recovery in the predetermined region of the base body formed of the shape memory alloy by irradiating an energy beam on the predetermined region for heating where the shape recovery of the base body formed thereof should be restrained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shape memory alloy shape recovery control method and a manipulator using the shape memory alloy.

[0002]

2. Description of the Related Art As is well known, a shape memory alloy (hereinafter referred to as S
MA) can have a shape memory effect of recovering the shape stored by heating by appropriate shape memory processing.

[0003] In an omnidirectional SMA, it is also possible to store the respective shapes at the time of high temperature and low temperature.

The SMA having such characteristics is used for various actuators, switches, sensors, and the like.

However, in an actuator or a sensor utilizing the shape recovery of the SMA, the fixing portion is subjected to repeated stress. Therefore, the fixing portion is loosened during use in mechanical fixing, or the bonding portion in the case of bonding. There were problems such as breakage.

Therefore, in the case of the SMA having such characteristics, it is necessary to prevent the SMA from recovering its shape even when heated, or to reduce the shape recovery.

Japanese Patent Publication No. 63-63623 discloses that a conductive layer is provided on the surface of a region where shape recovery of a shape memory alloy is desired to be suppressed, and a current is supplied to the conductive layer during energization and heating. There is disclosed a shape recovery control method for a shape memory element which suppresses a shape recovery by reducing a flowing current to suppress a temperature rise.

Further, as a manipulator using SMA as an actuator, a tubular manipulator is disclosed in Japanese Patent Application Laid-Open No. Hei 7-308884.

This tubular manipulator has a configuration in which a plurality of omnidirectional SMA plates are connected.

The heating of the SMA plate is performed by a heater attached to the surface of the SMA plate.

The SMA plate and the SMA plate are connected via a fixing ring member.

FIG. 5 is a sectional view of the fixing ring member 19.

The fixing ring member 19 has a fixing groove 20 for inserting an SMA plate.

After the SMA plate is inserted into the fixing groove 20, it is fixed by means such as bonding.

The shape of the SMA plate can be recovered by fixing grooves 2
Therefore, the fixed portion of the SMA plate is not easily damaged by the repeated shape recovery as described above.

[0016]

However, in the method for controlling shape recovery of a shape memory element disclosed in Japanese Patent Publication No. 63-63623 as the prior art described above, the S
Although it is effective when the MA is electrically heated, it is applicable when the SMA is heated by a heater as in the tubular manipulator disclosed in the above-mentioned prior art Japanese Patent Application Laid-Open No. 7-308884. Could not.

The first object of the present invention is to provide a method for controlling the shape recovery of a shape memory alloy which can suppress the recovery of the shape of an SMA even when heating with a heater.

Further, the above-mentioned prior art disclosed in Japanese Patent Application Laid-Open
The fixing ring member of the tubular manipulator disclosed in Japanese Patent No. 308884 has a complicated shape due to the formation of the fixing groove.

Then, S having a thickness of about several hundred microns
Since machining of the fixing groove having a size corresponding to the MA plate is difficult by cutting, it is performed by electric discharge machining, so that the machining cost is high.

[0020] In addition, there is a limit of fine machining even in electric discharge machining, which has been a constraint on miniaturization of the tubular manipulator.

Therefore, the present invention focuses on such a point, and suppresses the recovery of the shape of the fixing portion of the SMA plate, and adopts a configuration in which the SMA plate is merely attached to the surface of the fixing ring member having a simple shape. It is a second object of the present invention to provide a manipulator using a shape memory alloy, which is capable of using a shape memory alloy.

[0022]

According to the present invention, in order to solve the above-mentioned first problem, (1) a predetermined region in which a shape recovery of a base made of a shape memory alloy is to be suppressed is irradiated with an energy beam. A method for controlling shape recovery of a shape memory alloy is provided, wherein the shape recovery of a predetermined region of a substrate made of the shape memory alloy is suppressed by heating.

According to the present invention, in order to solve the first problem, (2) the method for controlling shape recovery of a shape memory alloy according to (1), wherein the energy beam is a laser. Is provided.

(Corresponding Embodiment of the Invention) This (1)
Embodiments relating to the inventions of (2) and (2) are, respectively,
A first embodiment described later corresponds to this.

In this embodiment, the shape memory alloy in the above configuration corresponds to the SMA plate 1, the predetermined area in which the shape recovery is to be suppressed corresponds to the bonding portion 2, and the energy beam corresponds to the energy beam 3. .

(Function) In the method for controlling shape recovery of a shape memory alloy according to the present invention, the shape recovery of the shape memory alloy is suppressed only at the portion to be bonded.
Since MA is used, shape recovery of the SMA is partially suppressed so as not to repeatedly apply stress to the bonded portion.

The present invention is effective not only when the SMA is electrically heated but also when it is heated by a heater.

According to the present invention, in order to solve the above-mentioned second problem, there is provided (3) a manipulator made of a shape memory alloy, wherein energy is supplied to a predetermined region where the shape recovery of a base made of the shape memory alloy is desired to be suppressed. A manipulator using a shape memory alloy is provided, in which a shape memory alloy is suppressed by recovering a shape of a predetermined region of a base made of the shape memory alloy by irradiating the shape memory with a beam.

(Corresponding Embodiment of the Invention) This (3)
An embodiment according to the invention of the first embodiment will be described later with first and second embodiments.
Corresponds to this embodiment.

The shape memory alloy in the above-described structure is the same as the SMA plate 1 of the first embodiment and the SSMA plate 1 of the second embodiment.
The MA plate 5 and the SMA plate 6 correspond to each other, and the predetermined region in which shape memory is desired to be suppressed corresponds to the bonding portion 2 in the first embodiment and the shape memory suppression region 10 in the second embodiment. The beam corresponds to the energy beam 3 of the first embodiment.

(Function) In the manipulator using the shape memory alloy of the present invention, since the SMA in which the shape recovery is suppressed only in the bonding portion is used, the SMA shape recovery is performed so that the bonding portion is not repeatedly subjected to stress. Partially suppressed.

For this reason, it is possible to have a simple structure in which the SMA is simply attached to the part to be bonded and fixed.
This is effective for reducing the cost of the manipulator.

The present invention is effective not only when the SMA is heated by energization but also when it is heated by a heater.

[0034]

Embodiments of the present invention will be described below with reference to the drawings.

(First Embodiment) FIG. 1 shows a method of controlling shape recovery of a shape memory alloy according to a first embodiment of the present invention.

In FIG. 1, reference numeral 1 denotes an SMA plate.

The SMA plate 1 is subjected to omnidirectional shape memory processing so as to be curved and deformed into a curved surface in a high temperature state and return to a flat plane shape as shown in FIG. 1 in a low temperature state. I have.

The SMA plate 1 is adhered and fixed to a holding member (not shown) and used as an actuator or the like.

Reference numeral 2 denotes a bonding portion for that purpose.

The adhesive portion 2 is locally irradiated with the energy beam 3 for a very short time of several tens msec or less.
Heating is performed instantaneously to a high temperature region where the shape memory effect is reduced, and the shape memory effect of a predetermined region irradiated with the energy beam 3 is reduced.

Reference numeral 4 is a shape memory suppressing unit.

Due to the local and short-time heating, the temperature hardly rises except for a predetermined area irradiated with the energy beam 3 and is not affected by the shape memory effect.

The irradiation of the energy beam 3 is as follows.
This process is repeated while shifting the position to reduce the shape memory effect in the area of the bonding portion 2.

As a result, even if the temperature of the bonding portion 2 becomes high, the shape of the bonding portion 2 hardly recovers. Therefore, even when the bonding portion 2 is simply bonded to the surface of the support member (not shown), the bonding portion 2 is repeatedly subjected to stress. No damage.

In the present invention, since the shape memory characteristics of the SMA itself are suppressed, even when heating is performed with a heater, the SM can be used.
The shape recovery of A can be suppressed.

Naturally, the SMA
Shape recovery can be suppressed.

It should be noted that, even if heating is performed locally and for a short time, if the heating is repeated at short intervals, the portion where the shape memory effect is desired may be thermally affected.

In such a case, the energy beam 3
Can be dealt with by increasing the time interval between the irradiations of the energy beam 3 so that the temperature outside the range of the irradiation is not too high.

The heated portion is oxidized in the air. If the oxidization becomes a problem, the oxidation can be prevented by irradiating the energy beam 3 while shielding with an inert gas.

Each configuration of the embodiment of the present invention is, of course,
Various modifications and changes are possible.

For example, the energy beam 3 to be heated locally and instantaneously may be a YAG laser, a CO ₂ laser, or an electron beam, and the same effect can be obtained respectively.

The shape of the SMA is not limited to a plate, but may be a wire or a coil.

The shape to be stored in the SMA may be not only a shape that is flat in a low temperature state and a shape that is curved in a high temperature state, but may be a shape that becomes flat in a high temperature state and bends in a low temperature state. In particular, the shape to be stored is limited. Never.

Further, the type of the shape memory of the SMA may be not only in all directions but also in one direction.

In the above-described embodiment, since the region where the shape recovery is to be suppressed is the bonded portion 2, as shown in FIG. 1, the entire area of the bonded portion 2 is irradiated with the energy beam 3 to recover the shape. Has been made to suppress.

However, the present invention can also be applied to a case where it is desired to suppress the shape recovery only partially to a certain extent other than at the bonded portion.

That is, in such a case, as shown in FIGS. 2A and 2B, by providing the shape memory suppressing portions 4 at a certain interval, a certain degree of shape recovery can be partially achieved. It is possible to suppress shape recovery while leaving.

FIG. 2A shows a configuration in which the shape memory suppressing sections 4 are formed as rows, and the rows are spaced from each other.

FIG. 2B shows a configuration in which the shape memory suppressing sections 4 are scattered at intervals.

(Second Embodiment) Next, a second embodiment of the present invention will be described.
A manipulator using a shape memory alloy according to the embodiment will be described with reference to FIGS. 3 and 4. FIG.

FIG. 3 is an exploded perspective view illustrating the structure of a manipulator using the shape memory alloy of the present invention.

In FIG. 3, reference numerals 5 and 6 are SMA plates, respectively.

These SMA plates 5 and 6 are omnidirectional shape memory so that they are curved and deformed into a curved state in a high temperature state, and return to a flat plane shape as shown in FIG. 3 in a low temperature state. Processing has been done.

The two ends of one SMA plate 5 are fixed to the base member 7 and the connecting member 8 by bonding.

Both ends of the other SMA plate 6 are fixed to the connecting member 8 and the tip member 9 by bonding.

In FIG. 3, the right side in the drawing is the distal end side of the manipulator, and the left side in the drawing is the base end side.

The SMA plates 5 and 6 are mounted so that the directions of the SMA plates 5 and 6 are respectively changed by 90 degrees, so that the manipulator can operate up, down, left and right.

The first and second parts of the present invention are attached to the bonded portions at both ends of the SMA plates 5 and 6, respectively.
The shape memory suppression region 10 formed by the shape memory alloy shape recovery control method according to the embodiment is provided.

The base member 7, the connecting member 8, and the distal member 9 are provided with a flat bonding surface 11 for bonding to the SMA plates 5 and 6, respectively.

The base member 7, the connecting member 8, and the distal member 9 each have a hollow pipe-like structure, and a cable from an end effector attached to the distal member 9 can be inserted therethrough.

In FIG. 3, reference numerals 12 and 13 are film heaters A and B, respectively.

Further, three heaters 14 are provided at an intermediate portion of the film heater A12.

The film heater B13 has two heaters 14.

By providing a plurality of heaters 14 as described above, the SMA plates 5 and 6 can be partially heated.

The film heater A12 is provided with a wiring lead-out electrode 15 and a connection electrode 16.

Further, a connection electrode 17 is provided on the film heater B13.

As a result, the film heater A12 and the film heater B13 are connected to the respective connection electrodes 16,
17 are connected.

Then, the electric power supplied from the wiring take-out electrode 15 of the film heater A12 is supplied to each heater 14 by the built-in wiring (not shown) of the film heater A12 and the film heater B13.

The SMA plates 5 and 6 as described above,
The base member 7, the connecting member 8, the distal member 9, the film heater A12 and the film heater B13 are adhered as shown by arrows in FIG. 3 to assemble the manipulator.

FIG. 4 is a perspective view showing the assembled state of a manipulator using the shape memory alloy of the present invention.

In this case, the portion of the connection electrode 17 of the film heater B13 is bent, and the film heater A
It is connected to twelve connection electrodes 16.

Further, by performing the necessary wiring for the wiring extraction electrode 15, power is supplied to each heater 1
4 are individually heated.

As a result, the SMA plates 5 and 6 are brought to a high temperature state and deformed into the stored curved shape.

When the supply of power is stopped, the SMA plates 5 and 6 are brought into a low temperature state by natural heat radiation,
Return to flat planar shape.

In the manipulator constructed as described above, each heater 14 is individually heated to allow the SMA plate 5
Care is taken that only the required ranges of and 6 can be heated.

However, when the heaters 14 are heated more than necessary, the temperature around the individual heaters 14 becomes high, and the shape of the SMA plates 5 and 6 may be recovered.

However, in the manipulator of the present invention, S
The shape memory suppression region 10 formed by the shape recovery alloy shape recovery control method according to the first embodiment of the present invention is provided on the bonded portions at both ends of the MA plates 5 and 6.
Is provided, the bonding portion between the SMA plates 5 and 6 and the base member 7, the connecting member 8, and the distal member 9 is SM
The A plates 5 and 6 are not damaged by the repeated stress due to the shape recovery.

Therefore, the structure of the bonding portion does not need to be provided with a fixing groove or the like as in the prior art, and may be a structure in which the bonding portion is simply affixed. The processing cost can be greatly reduced.

The simple structure of the base member 7, the connecting member 8, and the distal member 9 means that processing can be performed even if the size is reduced, and the entire manipulator can be reduced in size.

Note that each configuration of the embodiment of the present invention
Naturally, various modifications and changes are possible.

For example, the number of SMA plates is not limited to two, and the shape to be stored is not limited.

Further, not only the omnidirectional SMA but also a manipulator having a configuration combining a one-way SMA and a bias spring may be used.

Further, the heating method is not limited to the heater, but is also effective for the electric heating method.

In the present specification described in the above-described embodiments, in addition to claims 1 to 3 described in the claims, the inventions described below as supplementary notes 1 to 5 are provided. include.

(Supplementary Note 1) The shape recovery control method for a shape memory alloy according to claim 1, wherein the energy beam is an electron beam.

(Supplementary note 2) The control method of a shape memory alloy according to claim 1, wherein the predetermined region in which the shape recovery of the base made of the shape memory alloy is desired to be suppressed comprises a plurality of discrete regions.

(Supplementary note 3) The method for controlling shape recovery of a shape memory alloy according to claim 1, wherein the irradiation of the energy beam is performed up to a high temperature region where the shape memory effect is reduced.

(Supplementary note 4) The shape according to claim 1, wherein the irradiation of the energy beam to a predetermined region where the shape recovery of the base made of the shape memory alloy is to be suppressed is performed in an inert gas atmosphere. Method for controlling shape recovery of memory alloy.

(Supplementary note 5) The manipulator according to claim 3, wherein the predetermined region in which the shape recovery of the base made of the shape memory alloy is to be suppressed is a bonding portion between the base and the holding member.

[0100]

Therefore, as described above, claim 1 is as follows.
According to the present invention described in (2) and (3), the shape recovery of the SMA can be partially suppressed.
By suppressing the recovery of the shape of the fixed portion and the bonding portion of the MA, it is possible to prevent the fixing portion from being loosened or the bonding portion being damaged due to repeated stress, and to suppress the recovery of the shape of the SMA even when heating with a heater. A method for controlling shape recovery of a shape memory alloy can be provided.

According to the third aspect of the present invention,
A manipulator using a shape-memory alloy that is effective in reducing cost because it is possible to suppress the recovery of the shape of the fixing part of the SMA plate and to simply attach the SMA plate to the surface of the fixing ring member having a simple shape. Can be provided.

[Brief description of the drawings]

FIG. 1 is a perspective view for explaining a shape recovery control method of a shape memory alloy according to a first embodiment of the present invention.

FIGS. 2A and 2B are perspective views showing a modification of the shape recovery control method for the shape memory alloy according to the first embodiment of the present invention.

FIG. 3 is an exploded perspective view showing a manipulator using a shape memory alloy according to a second embodiment of the present invention.

FIG. 4 is a perspective view showing a state after assembling of a manipulator using a shape memory alloy according to a second embodiment of the present invention.

FIG. 5 is a cross-sectional view showing a fixing ring member for connecting between SMA plates according to the related art.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... SMA plate, 2 ... Adhesion part, 3 ... Energy beam, 4 ... Shape memory suppression part, 5, 6 ... SMA plate, 7 ... Base member, 8 ... Connection member, 9 ... Tip member, 10 ... Shape memory suppression Area: 11: Adhesion surface, 12: Film heater A, 13: Film heater B, 14: Heater, 15: Wiring take-out electrode, 16: Connection electrode, 17: Connection electrode, 18: Manipulator.

Claims (3)

[Claims] An object of the present invention is to irradiate an energy beam to a predetermined region of the substrate made of a shape memory alloy where the shape recovery is desired to be suppressed and to heat the region, thereby suppressing the shape recovery of the predetermined region of the substrate made of the shape memory alloy. A shape recovery control method for a shape memory alloy, comprising: 2. The method according to claim 1, wherein the energy beam is a laser. 3. A manipulator made of a shape memory alloy, wherein a predetermined region in which shape recovery of the base made of the shape memory alloy is to be suppressed is irradiated with an energy beam and heated, whereby a predetermined shape of the base made of the shape memory alloy is obtained. A manipulator using a shape memory alloy, characterized in that the shape recovery of the region is suppressed.