coupling device for regulating the speed of a likstromsmotor, serskilt for tandlekares handapparater

摘要

A circuit arrangement for controlling the speed of a D.C. motor, and particularly a motor for operating dental instruments. The circuit arrangement comprises a reference signal generator, a comparator which compares the reference signal with a second signal derived from the motor armature voltage to produce a regulating signal, and a regulator which is connected in the motor armature circuit and which is controlled by the regulating signal to provide a fluctuating D.C. voltage supply to the armature. A compensator is arranged to produce a correction signal which is dependent on the instantaneous motor armature current, the compensator being connected to the reference signal generator for summation of the correction signal with the reference signal. This provides for improved response in the supply of power to the motor, for example, when the motor loading is increased such as to increase the armature current but decrease the armature voltage.