Brake spring coupling for adjustment gears, in particular of seat adjustment devices, preferably for motor vehicles

摘要

The brake spring coupling, which is provided with a brake drum surrounding an adjustment shaft, has a helical torsion spring bearing against it on the inner drum casing and/or outer drum casing. The helical torsion spring is connected to, on the one hand a support member and on the other hand an actuator, in each case via one radial angle end, the helical torsion spring being loadable by the actuator with the effect of a reduction of its pressing force. The brake drum is arranged in a stationary manner while the actuator, the support member bringing about the transmission and the helical torsion spring tensioned between them are rotatable in the brake drum during reduction of the tensioning force. A brake spring coupling is now to be produced, in which support member, actuator and helical torsion spring remain in an essentially stationary position while the brake drum carries out a rotation movement during the displacement movement. To this end, the brake drum is connected in a rotationally fixed manner to an adjustment shaft which can be rotated by the adjustment gear, while the support member is held in a stationary manner on the housing of the adjustment gear. Such a brake spring coupling makes possible use thereof as a brake arrangement in a reducing gear which reduces the halting moment by gear steps and on the last step of which, which has the smallest moment, the brake drum is arranged in a rotationally fixed manner, and the drum is rotatable freely with the gear steps during the adjustment movement.