Robert Boschgmbh

Hans Bertsch

Dietrich Eckstein

Jacob Stolle

Michael Winzer

Proposed is a commutation device for a direct-current motor, designed to improve the ripples in the signal course (,) for the commutation current, so as to obtain reliably and error-free speed information with the aid of an electronic circuit. With the commutation device design according to the invention, the longitudinal edges of the collector bars (,) form an angle (&agr;) of more than zero degrees with the front longitudinal edge (,) of the contact face (,). On the one hand, this results in a reduction of the brush noise (airborne sound) and, on the other hand, in a lowering of the noise development (structure-born sound).

Direct current motor commutation device

An adjusting drive comprises an electric motor having a motor armature provided with a motor armature shaft, a worm transmission associated with the drive motor and having a worm shaft which is formed as a floatingly arranged extension of the motor armature shaft, the worm shaft having a free end provided with a convex end surface, a stationary running element on which the motor armature shaft is fixed in an axial direction when it is rotated in a rotary direction, so that a pitch angle of the worm shaft in connection with a flank angle of teeth of the worm shaft produce a load component extending transversely to a longitudinal axis of the worm shaft, the running element which cooperates with the convex end surface of the worm shaft having a running surface which is formed spatially relative to the longitudinal axis of the worm wheel so that it is inclined in direction of the loading component of the worm shaft.

Growing community of inventors

Lichtenau, Germany

Hans Bertsch