JPH10311273A - Rotational movement mechanism using shape memory material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotational movement mechanism to high-efficiently utilize the memory function of a shape memory material through structure is simple. SOLUTION: A rotational movement mechanism is formed such that a drive shaft 1 and a rotary cylinder 3 are intercoupled a plurality of wire rods, formed of a shape memory material 3, in a curved state. By storing a shape different from a state set at the shape memory wire rod 3, by arranging the rotational movement mechanism in either temperature atmosphere having temperature being partially higher than the transformation point of the shape memory material or temperature atmosphere having temperature being partially lower than the transformation point of the shape memory material 3, the shape change of the shape memory material 3 moves the rotary ring 3 in a specified direction from the drive shaft 1, the rotary ring 3 is rotated through displacement of a center of gravity and the rotation is transmitted to the drive shaft 1. By reversing the temperature, the rotation direction is also reversed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary motion mechanism using a shape memory material having a shape memory transformation point such as a shape memory alloy or a shape memory plastic used for toys, interiors, teaching materials, and the like.

[0002]

2. Description of the Related Art As described in "Shape memory alloy" (Hiraku Funakubo, industrial book), various rotary motion mechanisms utilizing shape change at the transformation point of shape memory material have been developed. Widely used for toys, interiors, teaching materials, etc.

A rotary motion mechanism using this shape memory material is:
One is a gravity engine, and furthermore, a rod-shaped shape memory element is bent into a U-shape between a crank rotating about a fixed axis and a drive ring rotating about an axis shifted from the fixed axis. There is a structure in which the drive ring is rotated by restoring the linear shape when it is set and immersed in a hot water tank.

[0004]

However, among them, it is said that the gravity type engine has a simple structure, but is inefficient, and one of the causes is that a temperature difference is caused in the vertical direction. In addition, since the eccentric direction is parallel to the gravity, it is difficult to generate a rotational force. For this reason, various mechanisms have been developed to increase the rotational force by making the force of the shape memory alloy asymmetric with respect to the axis.

However, the rotary motion mechanism using these shape memory materials has a large number of components and is expensive as toys, interiors, teaching materials, and the like.

[0006] An object of the present invention is to provide a rotary motion mechanism which can use the memory function of a shape memory material efficiently while having a simple structure.

[0007]

SUMMARY OF THE INVENTION The present invention comprises a drive shaft and a rotary ring, and directly or indirectly moves a plurality of wires made of a shape memory material between the drive shaft and the rotary ring in a curved state. The problem was solved by the connected rotary motion mechanism.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As a wire connecting a drive ring and a drive shaft in a curved state, a Ti-Ni-based shape memory alloy or the like whose transformation temperature falls within a temperature range in which the drive is operated is used.

[0009] The degree of bending of the shape memory with respect to the wire may be larger or smaller than the degree of bending of the connected wire.

Furthermore, the shape of the rotating ring is not limited to a circle.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The operation of the rotary motion mechanism according to the present invention will be described below based on specific embodiments. FIG. 1 shows an embodiment of a rotary motion mechanism 10 according to the present invention.

In FIG. 1, reference numeral 1 denotes a rotary drive shaft supported by a frame, and four rotary drive shafts each having a curvature of one direction of 0.7 mm.
A Ti-Ni shape memory alloy wire 2 having a thickness of 2 mm, a width of 130 mm and a length of 130 mm is connected to a rotating ring 3 made of stainless steel having an inner diameter of 200 mm in a curved manner in one direction.
The shape memory alloy wire 2 has a transformation point of 30 ° C. and stores a linear shape.

FIG. 2 shows a rotary motion mechanism 10 shown in FIG.
The operation state of is shown. 2A, the lower part of the rotary motion mechanism 10 is located in a cooling atmosphere A at 20 ° C. lower than the transformation point temperature, and the upper part is located in a heating atmosphere B higher than the transformation temperature of 40 ° C. It shows a state in which they are arranged so as to be positioned. In this state, the shape memory alloy wire 2 in the upper part of the atmosphere B in the high temperature atmosphere tries to return to the linear state of the shape memory, and as a result, the center of gravity of the rotating ring 3 is eccentric to the upper left as shown by the arrow X and rotated. A force Y is generated. Then, as shown in FIG. 2B, the rotating ring 3 having generated this rotational force balances the forces f of the upper right and upper left shape memory alloys by the rotation thereof, but the upper left shape memory alloy is As a result of the force f trying to follow the straight line acting on the rotating ring 3 as shown by the arrow X, the center of gravity is eccentric, and further, a rotating force acts as shown by the arrow Y.

When the ambient temperatures A and B are reversed, the rotation direction is also reversed.

In this manner, the rotation of the rotary ring 3 is continued as long as the temperature-atmosphere relationship indicated by A and B is maintained.

[0016]

【The invention's effect】

(1) Since the shape memory wire is curvedly connected to the drive shaft, the amount of eccentricity of the rotary ring with respect to the drive shaft is not parallel to the direction of gravity, and the efficiency is high as a gravity type engine.

(2) The weight of the rotating ring and the shape memory alloy itself is used as the driving force, and the number of parts is small and the structure is simple, so that the cost is low.

(3) Since the structure is simple and the operating principle is easy to understand, it is suitable as a teaching material.

[Brief description of the drawings]

FIG. 1 shows an embodiment of a rotary motion mechanism of the present invention.

FIG. 2 shows an operating state of the rotary motion mechanism of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Rotation drive shaft 2 Shape memory alloy wire 3 Rotation ring 10 Rotational movement mechanism A Cooling atmosphere B In high temperature atmosphere X Arrow Y Rotational force f Force

Claims (2)

[Claims] 1. A rotary motion using a shape memory material having a rotating shaft and a rotating ring, wherein a plurality of wires made of a shape memory material are connected in a curved state between the rotating shaft and the rotating ring. mechanism. 2. The rotary motion mechanism using a shape memory material according to claim 1, wherein the plurality of wires are curved in one direction.