Patent ID: 6766888
Filing Date: 2004-07-27
Classification: F16D

Abstract:
A rotation transmission device comprising:an inner member; an outer member coaxially mounted with respect to said inner member such that said inner member and said outer member are operable to rotate relative to each other; a retainer mounted between said inner member and said outer member, said retainer having a plurality of pockets formed therein; engaging elements arranged in said pockets of said retainer; an armature mounted so as to be non-rotatable relative to said retainer and so as to be axially movable relative to said retainer, said armature having an attracted surface, said attracted surface having a radially outer section and a radially inner section; a rotor mounted to one of said inner member and said outer member so as to axially oppose said attracted surface of said armature, said rotor and said armature being shaped and arranged so that an entire circumference of only said radially outer section of said attracted surface of said armature is operable to contact said rotor; and an electromagnet for attracting said armature to said rotor so as to change a position of said retainer from a neutral position to an engagement position whereat said engaging elements engage an outer periphery of said inner member and an inner periphery of said outer member to thereby transmit rotational torque between said inner member and said outer member.