ELEKTROMOTORAANDRIJFSTELSEL MET VARIABEL TOERENTAL.

摘要

Variable-speed electric motor drive includes a universal motor having a power supply line wherein a thyristor is connected and operated in a phase gating circuit, a firing circuit for the thyristor, a variable first resistance connected to the firing circuit of the thyristor for varying the rotary speed of the motor, and a temperature-dependent second resistance associated with the firing circuit and thermally coupled to the thyristor.