Patent ID: 7516822
Filing Date: 2009-04-14
Classification: B60T,F16D

Abstract:
1. A parking brake for a vehicle comprising: an electric motor driven to rotate an internally threaded nut; a shaft having an external thread and received within said internally threaded nut, said shaft being constrained from rotating by being connected to an actuator member; said actuator member being connected to a brake mechanism such that said actuator member is movable between two extreme positions to in turn move said brake mechanism between a park position and a release position; and a control for driving said electric motor to rotate and cause said shaft to move, and in turn cause said actuator member to move said brake mechanism between said park and said release positions, said shaft driving a lever to pivot, said lever carrying a cam surface which cams a brake disc into engagement with a driveline structure to be locked to provide said park position; said control for sending a pulse to drive said electric motor in a particular direction to in turn move said shaft in an appropriate direction to move said brake mechanism between said park and said release positions; and said control for supplying a pulse length to said electric motor, said pulse length being longer than that necessary to move said shaft to drive said actuator member and move said brake mechanism between said park and said release positions.