Electric parking brake actuator for motor vehicle, has gear rotatably driven by constant torque motor, and screw meshed in toothed crown that is integrated to gear and rotatably driven by motor that applies force on periphery of gear

摘要

The actuator (1) has a constant torque motor for moving a movable part (28) along a locking direction that is determined when the actuator is actuated. A gear (3) is rotatably driven by the motor and includes spiral grooves (26, 27) that are centered on a rotation axis (4) of the gear. The movable part includes rollers (31, 32) which are guided by the spiral grooves, where the grooves have a variable step. A toothed crown (13) is rotatably integrated to the gear. A screw is meshed in the crown and is rotatably driven by the motor that applies a force on a periphery of the gear.