Patent ID: 7178653
Filing Date: 2007-02-20
Classification: F16D

Abstract:
1. An electromagnetic clutch for intermittently transmitting motive power from a driving source to a driven device, comprising: an electromagnetic coil for producing an electromagnetic force when energized; a rotor adapted to receive the motive power from the driving source; an armature plate movable between a position where the armature plate is in contact with the rotor and a position where the armature plate is spaced from the rotor, the armature plate being attracted toward the rotor by the electromagnetic force produced by the electromagnetic coil; a boss coupled to a main shaft of the driven device; and a leaf spring having one end serving as a first coupling portion coupled to the armature plate and the other end serving as a second coupling portion coupled to the boss, the leaf spring having an elastic force set such that when the electromagnetic coil is de-energized, the leaf spring keeps the armature plate spaced from the rotor, and that when the electromagnetic coil is energized, the leaf spring allows the armature plate to come into contact with the rotor against the elastic force thereof; wherein: said leaf spring comprises an inclined portion extending at a predetermined inclination angle from the boss toward the armature plate, and an extended portion parallel with the armature plate and located between the inclined portion and at least one of the first and second coupling portions; wherein a straight line extending substantially along a centerline of said leaf spring and extending from the first coupling portion intersects at an obtuse angle with a rotating direction of the armature plate.