| 摘要 |
PURPOSE:To prevent the fatigue breakdown of a spring due to an increase in the amount of flexure, by forming an elastic means of a configuration memory alloy in an apparatus wherein an armature is attracted against the elastic means such as the spring so as to be put in the state wherein a power is transmitted when an electromagnetic coil is excited. CONSTITUTION:When an electromagnetic coil 11 is excited, an armature 7 is attracted against a coil spring or a plurality of coned disc springs (hereinafter called springs) 8 by a magnetic path phi formed through a fixed core 15 to be connected to the fixed core 15, whereby the rotation of a driving shaft 2 is transmitted to a shaft 9 to be driven. The springs 8 are formed of a configuration memory alloy so as to have a flexure-load characteristic shown in the figure. By this constitution, a stress generated in the springs 8 when the amount of flexure thereof is increased with an increase in a gap 13 between the armature 7 and the fixed core 15 is suppressed to be nearly constant, and thereby the fatigue breakdown of the springs 8 can be prevented effectively. |
