RPM regulation of an electromotor

A device for regulating the RPM of an electromotor with an RPM generator coupled to it for generating pulses, measures the intervals between the pulses of a measure of the RPM of the motor. The device includes an oscillator for generating clock signals, which are transmittable to a counter, which counts the number of clock signals between successive pulses of the oscillator, a register, which accepts the counter indication and a device for generating a control value for correcting the RPM of the electromotor over a digital-to-analog converter connected in series to the motor. To generate the control value for regulating the RPM, and RC network containing a manually adjustable control resistance is provided, the capacitor of which can be short-circuited by a switch, which can be activated by an oscillator-driven contact mechanism. The capacitor is additionally connected to a circuit element for switching on the counter, whose switching off can be activated by the oscillator-driven contact mechanism.