| 摘要 |
PURPOSE:To obtain a fireproof switch equipped with the posture display function, vibration detecting function and temp. detecting function of an instrument such as a heater, by forming a shaking member and a magnetism diffusing part from a shape memory alloy. CONSTITUTION:A rocking member 7 made of a shape memory alloy holds the shape shown by a solid line at definite temp., for example, at 150 deg.C or less and shape memory is preliminarily applied to said shaking member 7 so that the shaking member 7 is bent as shown by a dotted line 7' when exceeds said temp. When the rocking member 7 is bent, the position of the center of gravity of the member 7 displaces and, therefore, the upper end part of the member 7 is inclined to the left to be brought into contact with the inner wall of a recessed part 3a. When the bending of the shaking member further advances thereafter, a magnetism diffusion part 8a moves while inclines to reach a position 8a'. Since the distance between a permanent magnet 8 and a reed switch 5 changes by this rocking, the change of a magnetic field is generated to bring a switch to an ON-state and a circuit is closed to output a signal to a control circuit for controlling the supply of fuel. By this constitution, a fireproof switch equipped with the posture display function and vibration and temp. detecting functions of an instrument such as a heater is obtained.
|
