ROTARY ELECTROMECHANICAL ACTUATOR, PARTICULARLY FOR A PARKING BRAKE FOR A MOTOR VEHICLE

摘要

A rotary electromechanical actuator rotationally drives a spool member (20) for operating a flexible transmission means in a motor vehicle. The actuator comprises two speed-reduction stages connected in series. The first speed-reduction stage is a worm gear system with a worm (11) rotated by an electric motor (12) and a helical gear (13). The second speed-reduction stage is a planetary gear system with a central gear (14) rigidly connected to the helical gear (13), an internally toothed ring gear (15) fixed to a stationary casing (16), a series of planet gears (17) rotating on pins (18) attached to a planet carrier (19) rigidly connected to the spool member (20). The teeth of the helical gear (13) are coaxial and lie around and axially approximately level with the planetary gear system.