Patent ID: 6543587
Filing Date: 2003-04-08
Classification: B60T

Abstract:
A brake assembly for a rotatable shaft of a vehicle, comprising:a rotor for mounting to the shaft of the vehicle for rotation therewith, the rotor having an annular braking surface, the shaft having an axis; a hydraulic piston axially movable relative to the rotor, the piston having a braking surface for frictionally engaging the braking surface of the rotor when hydraulic fluid pressure is supplied to the piston; a coil body having an electromagnetic coil therein; a coil plate axially moveable relative to the rotor, the coil plate being movable toward the coil body and away from the rotor in response to electrical power being supplied to the coil; and a coil spring mounted between the coil plate and the coil body that moves the coil plate away from the coil body and toward the rotor when the electrical power is removed from the coil, the coil plate being operatively engaged with the rotor to cause braking action preventing rotation of the rotor when the electrical power is removed from the coil; wherein the coil plate is located between the braking surface of the piston and the coil body, such that the coil spring acting against the coil plate causes the coil plate to push the braking surface of the piston into engagement with the braking surface of the rotor when electrical power is removed from the coil.