To provide a torque limiter capable of obtaining a large hysteresis torque.
A torque limiter includes a case 12 to an inner circumferential surface with a hysteresis material 16 fixed, and a shaft 14 to an outer circumferential surface with a permanent magnet 18 fixed, the hysteresis material 16 and the permanent magnet 18 are arranged opposite to each other with a specified clearance, and the case 12 and the shaft 14 are arranged in a concentric and rotatable manner with each other. The torque is transmitted between the case 12 and the shaft 14 by the hysteresis torque generated between the hysteresis material 16 and the permanent magnet 18. Since the hysteresis material 16 is formed of an anisotropic Fe-Cr-Co semi-hard magnetic material, the magnetic characteristic can be increased, the hysteresis are is increased, and the hysteresis torque can be increased. The anisotropic direction of the Fe-Cr-Co semi-hard magnetic material is preferably the radial direction or the circumferential direction.
SAKAMOTO FUMIO
KIMURA YOSHIBUMI
