Variable torque single-phase asynchronous MOTOR - has third winding switched in series with main and auxiliary windings

摘要

The variable-torque, single-phase asynchronous motor has a third winding in series between the main winding and an auxiliary winding. The ends of this third winding are connected to a switch so that with the switch in one position one of the supply poles is connected directly to the junction between main and third windings, whilst in the other switch position this supply pole is connected to the junction between third winding and auxiliary winding. The other supply pole is permanently connected to the other end of the main winding. The third winding fits into at least two slots in the motor armature.