Power transfer interruption mechanism between vehicle engine and compressor, has running surface in rotor to move spring so heel end of spring detaches from transmission surface of rotor

摘要

A running surface (51) is formed at the inner periphery of a rotor (41). A twist spring (47) is between the rotor and a compressor shaft (16). When excess torque is produced by the shaft and rotor rotation, the spring moves along the running surface and generates moving force that assists in detaching the heel end (47a) of the spring from the power transmission surface (43a) of the rotor. With the spring heel end abutted to the power transmission surface as well as a restriction surface (43b) at the rotor inner periphery, the twist facilitates power transmission from the shaft to the rotor.