JPS61269684A - Shape deforming device - Google Patents

Abstract

PURPOSE:To increase the utilizing range of a shape memory alloy (SMA) by detecting the temperature of the SMA, and forcibly deforming the SMA in response to the temperature. CONSTITUTION:When a temperature sensor 3 generates a signal of temperature 'low', the switch of a temperature controller 5 is closed, a current flows from a power source 4 through an SMA1 and the controller 5 to heat the SMA1. When the SMA1 is heated to exceed its deforming temperature, the SMA1 is bent to the right side and deformed. When the sensor 3 generates a signal of temperature 'high', the switch of the controller 5 is opened to cool the SMA1, and the SMA1 is returned to the original state. At the time, the SMA1 may be forcibly cooled.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a device that performs shape deformation using a shape memory alloy.

[Conventional technology]

Recently, shape memory alloy (Shape Memory A1
(referred to as 1o7 or less 8MA) is an alloy that has two functions: a temperature sensor and an actuator that acts on its own using the sensor, and its range of use is expanding. For example, various applications were introduced in the Asahi Shimbun (morning edition) ``Science of Life'' on November 9, 859, and KK Agne ``Science of Life'' was introduced.
Metal J May 19B4 issue VotS4. No, 5p2
8 to 8 describe the practical application to the wind direction adjustment mechanism of an air conditioner.

When ordinary metals are deformed beyond their elastic limit, they become plastically deformed and never return to their original shape.

However, SMA recovers its shape even if plastic strain is applied. Kneading and deformation are performed by reversible martensitic transformation, and the shape memorized at a high temperature is deformed at a low temperature below the temperature at which martensitic transformation occurs. Conversely, when the temperature is increased, a reverse transformation occurs from the martensite sum to the original matrix, and the material deforms to the original shape that was memorized at the high temperature.

These alloys include Ti-Ni system and (u system, Ou system, C!u-Zn alloy, Ou-At alloy, l:!u
-Zn-At alloy etc. are used. The temperature at which deformation occurs varies depending on the type of alloy, processing, heat treatment, etc., and various applications have been made to cause deformation at a predetermined temperature.

[Problem that the invention seeks to solve]

Conventional SMA applications have been limited to deforming the shape in response to the surrounding temperature, and there have been few examples of forcibly deforming the SMA itself.

Further, the response speed of the deformation operation of the SMA is slow, and there are cases where it is desired to increase the response speed, for example, when using the SMA in a robot or the like.

This invention was made to solve the above-mentioned problems, and provides a shape-deforming device that forcibly deforms an SMA, and also provides a shape-deforming device that speeds up the deformation response of the SMA. The purpose is to obtain.

[Means for solving problems]

The shape-deformable product according to this invention is heated to 5MA1.
The device is equipped with a means for cooling the EiMA, a means for detecting the temperature of the SMA, and a temperature control means for controlling heating and cooling of the EiMA based on a signal from the temperature detecting means.

Moreover, the second invention adds the above-mentioned heating/cooling means in response to an external command.

Further, the third invention is provided with deformation detection means for detecting the deformation state of the EIMA in place of the temperature detection means of the SMA of the first invention.

Furthermore, the fourth invention includes a temperature detection means for the SMA, and a temperature detection means for the SMA.
The deformation detecting means is provided with both deformation detecting means.

[Effect]

When the shape deformation device according to the present invention detects the temperature of the SMA, it controls the deformation operation of the SMA by increasing or decreasing the temperature of the SMA through the SMA heating/cooling means according to the detected temperature.

If the temperature is maintained near the deformation temperature of the second invented SMA and a shape deformation command is given from the outside, the SMA deforms quickly.

The third invention controls the deformation operation of the SMA by increasing or decreasing the temperature of the SMA through the SMA heating/cooling means in response to a deformation signal from the shape deformation detection means.

Fourth invention SMA I7) Detect both the temperature and the deformation state, and control the deformation operation of the SMA according to both signals.

[Examples of actual rights to inventions]

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

In Figures 1(a) and (b), fil is a rod-shaped S
MA, (2) is a support part, (3) is a temperature sensor, (4) is a power source, and (5) is a temperature controller (hereinafter referred to as a controller) for controlling the temperature.

In FIG. 1(a), the SMA fil is bent to the left at room temperature. When a temperature "low" signal is issued from the temperature sensor, the switch of the temperature controller (5) closes, and a current of 19 MA (11, t) flows from the power supply (4) through the controller (6).
Heat liMA +I+. (Heating may be done indirectly using a nichrome wire, hot air fan, etc.') SMA
(11 is heated and exceeds its deformation temperature as shown in Figure 1 (b
), the SMA (11) bends to the right and deforms.Then, when the detection signal from the temperature sensor (3) emits a high temperature signal, the switch of the controller (61 opens and the SMA
(1+ is in the cooling phase and returns to the state shown in FIG. 1(a). At this time, the cooling of SMA +11 is natural cooling, but forced cooling such as blowing cold air or cooling with a cooler may also be used. From the above, Figure 1 (a) and (b)
This state can be repeated, and can be used, for example, in the reciprocating motion of robot legs or machine tools. In addition to continuing the reciprocating motion, the power supply (4) is turned on and off externally, and this circuit is utilized only when necessary, so that it operates once,
The operation may be performed twice. In addition, the controller (
6) shows an example of ON-OFF control, but a control means that performs proportional control, MD control, etc. may also be used.

Further, the temperature sensor may be one that indirectly detects the temperature, such as a radiation thermometer.

Figure 2 (a) p (b) a shows another practical example of this invention, in which (6) is a coiled sm which is stored so as to contract when the illuminance exceeds the deformation intensity. (7) is the load, (8)
is a current/temperature converter (
(hereinafter referred to as a converter). If the signal from the converter is higher than the deformation temperature of SMA (6!) in the state shown in Fig. 2 (a), the controller (51 is turned on and current flows, and the SMA
When (6) is heated and the temperature exceeds the deformation temperature of SMA +61, the SMA (61) contracts as shown in Figure 2 (1), increasing the load (7).
When a signal is sent out that is higher than the deformation temperature of the controller (51
becomes OFF, and SMA +61 becomes @? The state shown in Figure (a) will be reached. In this way, the vertical movement of the load (7) can be repeated. As in the case of FIG. 1, the power supply (4) may be turned on and off from the outside, and this circuit may be operated only when necessary.

! 3 and 4 are diagrams showing one embodiment of the invention of ffIJ2, and FIG. 4 is a diagram of the main part of the specific example of FIG. 3.

In the figure, tIO+ is the first temperature control means, which receives a signal from the temperature sensor (31) and maintains the temperature at a temperature slightly above or below the deformation humidity of SMA (6). Controller controlled by limiter (
It is equipped with 61. αD is a second temperature control means, which controls the controller (6) by external commands for increasing and decreasing the temperature.
Equipped with a heating/cooling instruction circuit that gives specific instructions for heating and cooling. (E) and (F) are an upper limit setter and a lower limit setter, and if the deformation temperature of SMA +11 is t-50°C, they are set to 55°C and 45°C, respectively.

(branch).

The @ke comparator outputs a signal (TA) when the upper/lower limit setter... (2) set temperature becomes 55°C or higher or 45°C or lower.

(TB), drives the one-shot multis (To) and (To), and sends the (To) and (TD) signals to the controller (5).
1, the current is limited to keep it at 55°C when it is over 55°C, and the current is increased to keep it at 55°C when it is below 45°C.
The controller is used to maintain the temperature. Now, SMA (1
1 is at room temperature (e.g. 20°C), the comparator -
, the one-shot multi (7) operates to generate a signal (TD), and the controller (61-digit SMA) maintains the temperature at 11 or 45°C. When entering, the gate (To) sends out the signal (Tm) because the signal (To) is OF"?.The controller (5) sends out the signal (To).
TI), the current is increased to heat BMA +11 above the deformation temperature and deform it.

BMA (II temperature is upper limit setter (1) set value 55
When the temperature exceeds ℃, comparator (goods), one-shot multi (
c) operates, generates a signal (TO), turns off the gate (TO), and stops the signal (Tl!:), and the controller (6) turns on the BMA [11 to 55] by the signal (TC).
Controlled to maintain temperature at ℃. In this way, III
MA +11 is deformed and SMA fi+ is held at 55°C near its deformation temperature (50°C).

Next, when a temperature (down) signal is input by an external command, a signal (TF) is sent through the gate (support) and the controller (6)
keSMA [Limit the current flowing to 11 and OFF L
When the temperature of SMA (11) is lowered, and BMA [11 becomes its deformation temperature below 50°C, it deforms and returns to its original shape, and when it becomes below 45'C, the comparator (to), opposite to the upper limit side, One-shot machining chip (2) works and SMA
(The temperature of No. 11 is maintained at 45°C. This operation is shown in the time chart of Fig. 5. When the external command (up) signal is input, the heating current ) flows, and the temperature rises as shown in (101). When the deformation temperature reaches 50℃, SMA (II
01) and reaches 202). When the temperature reaches 55℃, the heating current is controlled to (b) and becomes (102
) becomes constant. Next, when the (aown) signal is input, the heating current decreases as (/), the temperature becomes below the deformation temperature as (I3), and BMA +11 #:t(20
3) Transform. When the temperature reaches 45°C, the current is controlled as in ) to keep it constant as in (1D4). In this way, from the outside (up) (aown)
The deformation signal of SMA il+ is controlled by the deformation signal of h.
At the same time, the deformation temperature is 55℃ or d45'c near 50℃.
Since it is held in place, the deformation operation time can be shortened. In other words, it is possible to shorten the time from receiving a deformation command to deformation, so it has the characteristic of increasing the response speed for robot movement, machine tool control, and other things that utilize 8MA movement. Can be done.

. The one-shot multi in Figure 4 is omitted and the analog value signal (
TA) (TB) may be input directly to the controller (61) for detailed control using analog control such as proportional control.Also, the entire system may be digitized and controlled digitally, or controlled by a microcomputer. good.

In the above example, a current is passed directly to the SMA to heat it, but 1
Indirect heating may also be used. Furthermore, if the deformation temperature is below normal temperature, the same effect as in the above-mentioned example can be achieved by cooling instead of heating. Further, by using both the heating means and the cooling means, the deformation response can be made faster than ever before.

The sixth example is an embodiment related to the third invention, which was realized by detecting the deformation of the SMA instead of the above-mentioned temperature sensor. is detected and the current is controlled by the controller (5), and its operation is the same as the first factor.In addition to strain gauges, detection of deformation due to light, and objects moved by the BMA that straddle the BMA. Attach the mag foot to the BMA
The deformation of the magnet may be detected by a magnetic sensor or the like based on the crushing of the magnet. In this case, since the operation of the BMA itself is detected rather than using a temperature sensor, there is an advantage that it is not affected by external changes in temperature.

Fig. F is a diagram showing an embodiment of the invention of HgFI4,
The controller (
6), for example, the temperature sensor (31) and the strain gauge (e) can be used as a dual system to improve reliability, especially in controlling robots and machine tools. can contribute to improvement.

In addition, as a modification of FIGS. 3 and 4, the temperature sensor controls the upper and lower limits of the temperature.
By using the strain gauge (7) as an inhibit signal for the gate (1) and @ based on an external command, the response of the deformation control can be made smooth.

This means that when the SMA deforms, the gate (ho) and 7S
: An inhibit signal is added to the system, so there is no extra heating or cooling, and therefore overshoot can be easily prevented and contributes to system stability.

〔Effect of the invention〕

As described above, according to the present invention, the temperature of the SMA is detected and the SMA is forcibly deformed in accordance with this temperature, so that the range of use of the SMA can be expanded. Further, in the second aspect of the invention, by adding a deformation command signal from the outside, it is possible to speed up the deformation response of the SMA to the command. In the third invention, the deformation state of the EiMA is detected and the BMA is forcibly deformed in accordance with this signal, thereby expanding the range of use of the BMA. Detection has the effect of contributing to improved reliability and stability of the response system.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram of a shape deforming device according to one embodiment of the present invention, and FIGS. 2, 3, 6, and 7 are circuit diagrams of a shape deforming device according to other embodiments of the present invention. Figure 4 is a circuit diagram showing a specific example of the main part of Figure 3, and Figure 5 is a circuit diagram of Figure 3, 4IP!
14 shows a time chart of the operation of the embodiment shown in FIG. In addition, are the same symbols in the figures the same or equivalent parts? show.

Claims (11)

[Claims] (1) A shape memory alloy that deforms at a predetermined temperature, a heating means for heating and/or cooling the shape memory alloy, a means for detecting the temperature of the shape memory alloy, and a means for detecting the temperature of the shape memory alloy in response to a detection signal from the temperature detection means. A shape deforming device comprising temperature control means for controlling the heating means to adjust the temperature of the shape memory alloy. (2) The shape-deforming device according to claim 1, wherein the heating means is a means for heating the shape-memory alloy by passing an electric current through it. (3) The shape deforming device according to claim 1, wherein the heating means is means for blowing at least one of hot air and cold air onto the shape memory alloy. (4) When the signal from the temperature detection means is lower than the deformation temperature of the shape memory alloy, the temperature control means increases the temperature of the shape memory alloy through the heating means, and the signal from the temperature detector increases the temperature of the shape memory alloy when the signal from the temperature detection means is lower than the deformation temperature of the shape memory alloy. Claims characterized in that if the signal is higher than the deformation temperature of the memory alloy, the temperature of the shape memory alloy is lowered through the heating means, and the shape of the shape memory alloy is repeatedly changed. The shape deforming device according to any one of items 1 to 3. (5) A shape memory alloy that deforms at a predetermined temperature, a heating means for heating and/or cooling the shape memory alloy, a means for detecting the temperature of the shape memory alloy, and a signal from the temperature detection means. A shape deforming device comprising: a first temperature control means for controlling the heating/cooling means in accordance with the heating/cooling means; and a second temperature controlling means for controlling the heating/cooling means according to an external command. (6) The second temperature control means increases the temperature of the shape memory alloy through the cooling heating means when the temperature is lower than the deformation temperature according to an external command, and lowers the temperature when the temperature is higher than the deformation temperature. The first temperature control means is a control means for deforming the shape memory alloy, and when the signal from the temperature detection means becomes a signal lower than the deformation temperature of the shape memory alloy, the first temperature control means is controlled to be lower than the deformation temperature and close to the deformation temperature. The heating means is controlled to maintain the temperature of the shape memory alloy at a temperature of , and when the signal from the temperature detection means becomes a signal higher than the deformation temperature of the shape memory alloy, 6. The shape deforming device according to claim 5, further comprising means for controlling said heating means to maintain the temperature of said shape memory alloy at a temperature close to that temperature. (7) A shape memory alloy that deforms at a predetermined temperature, a heating/heating means for heating and/or cooling the shape memory alloy, a deformation detection means for detecting the deformation state of the shape memory alloy, and the deformation detection means A shape deforming device comprising temperature control means for controlling the heating and cooling means in accordance with a detection signal. (8) The shape deforming device according to claim 8, wherein the deformation detecting means is a means for detecting by an optical sensor. (9) Claim 7, characterized in that the deformation detection means uses a strain gauge attached to at least one of a shape memory alloy and a member operated by deformation of the shape memory alloy.
Shape deformation device as described in section. (10) The temperature control means increases the temperature of the shape memory alloy through the heating means when the signal from the deformation detection means is a signal indicating a shape state when the shape of the shape memory alloy is lower than its deformation temperature; If the signal from the deformation detection means is a signal indicating the shape state when the shape of the shape memory alloy is higher than its deformation temperature, the temperature of the shape memory alloy is lowered through the heating means, and the shape memory alloy is 10. A shape-deforming device according to claim 7, characterized in that the shape-deforming device is a means for repeating shape changes. (11) a shape memory alloy that deforms at a predetermined temperature; a heating/heating means for heating and/or cooling the shape memory alloy; a temperature detection means for detecting the temperature of the shape memory alloy; A shape deforming device comprising: a deformation detecting means for detecting a deformed state; and a temperature controlling means for controlling the heating and cooling means according to detection signals from the temperature detecting means and the deformation detecting means.