Patent ID: 7455160

Claim:
An electromagnetic clutch comprising: a drive shaft of a compressor in an air conditioner for a vehicle in which a combustible refrigerant or a CO 2 refrigerant circulates; a rotor adapted to be rotated about said drive shaft by receiving a motive power from an engine or a motor of said vehicle; an armature disposed so as to face said rotor; an electromagnetic solenoid for making said rotor attract said armature by causing a current to flow therethrough and transmitting the motive power to said drive shaft; and a torque limiter connected to said armature through an elastic member and adapted to be rotated integrally with said drive shaft, wherein said torque limiter is provided with a transmission cutting-off portion for, when the state of a lock is caused in said drive shaft, perfectly separating the armature side from the drive shaft side, and for, unless the lock state is released, prohibiting the connection between the armature side and the drive shaft side from being recovered.