Electromagnetic coupling

摘要

Disclosed is an electromagnetic coupling designed to strengthen the magnetic force exerted from an electromagnetic coil in the direction in which a pilot clutch is operated. In the electromagnetic coupling with the pilot clutch (9) for activating a main clutch (3) wherein clutch plates (9a, 9b) are thrust with a retaining ring (10) moved by magnetic force produced by an electromagnetic coil (23) in the pilot clutch, the electromagnetic coil in the pilot clutch is surrounded with ferromagnetic material (24) over at least two of its three facial sides other than its magnetic force exerting facial side, namely over at least its rear and outer facial sides and the ferromagnetic material is covered with nonmagnetic material (22). <IMAGE>