Patent ID: 6755284
Filing Date: 2004-06-29
Classification: B60T,Y10T

Abstract:
A power-driven parking brake actuation assembly for actuating a vehicle brake system via a brake activation linkage, the power-driven parking brake actuation assembly comprising:an electric motor; a first rotatable member operatively connected to the electric motor so as to enable the motor to rotate the first rotatable member in a brake applying rotational direction, the first rotatable member normally being prevented against rotation in an opposite brake releasing rotational direction; a second rotatable member rotatable relative to the first rotatable member, the second rotatable member including a brake linkage actuator connectable to the brake activation linkage movable to actuate the brake activation linkage; a torsion clutch spring disposed between the first and second rotatable members, the torsion clutch spring being configured to contract upon initiation of rotation of the first rotatable member by the motor in the brake applying direction so as to couple the second rotatable member with the first rotatable member for affecting rotation of the second rotatable member in the brake applying direction for actuation of the brake activation linkage, the clutch spring also contracting upon initiation of rotation of the second rotatable member in the brake releasing direction so as to couple the second rotatable member with the first rotatable member for enabling the first rotatable member to prevent rotation of the second rotatable member in the brake releasing direction; and a manually actuable brake release mechanism including a manually movable release member mechanically connected to the clutch spring such that manual movement of the release member expands the clutch spring to de-couple the first and second rotatable members, thus enabling the second rotatable member to rotate in the brake releasing direction, wherein the clutch spring expands upon initiation of rotation of the first rotatable member in the brake releasing direction and wherein the motor is reversible to rotate the first rotatable member in the brake releasing direction opposite the brake applying direction to expand the clutch spring and de-couple the first and second rotatable members, thus enabling the second rotatable member to rotate in the brake releasing direction.