Patent ID: 7023167

Claim:
A compressor with motive power provided by an induction motor having at least three windings, and a torque-augmentation circuit comprising a starting capacitor and a resistive element connected electrically in series between two of the motor winding terminals, the compressor further including: a rotatable shaft, a gas source, a gas receiver, a single-phase electrical source with first and second supply lines, means connecting the motor windings in a closed delta configuration with first, second, and third delta corner terminals, first piping means to connect said gas source to the inlet suction port, second piping means to connect the outlet pressure port to the gas receiver, the rotatable shaft driven by the shaft of the induction motor, the single-phase electrical source first supply line connected through a switch to a power source terminal electrically connected to the first delta corner, the single-phase electrical source second supply line connected to the second delta corner, a torque augmentation circuit with first and second starting terminals consisting of a starting capacitor in series with an electrical component with conductance or resistance, a first starting terminal connecting said electrical component to one pole of an electrically-conductive connection means, the other pole of said electrically conductive connection means connected to the third delta corner terminal, a second starting terminal being the terminal of the starting capacitor not connected to the electrical component, means to connect said second starting terminal to the power source, and a static enabler means containing a motor-run capacitor connected between the power source and the third delta corner terminal, an autotransformer with first and second terminals and one winding tap intermediate between the first and second terminals, a connection of the first terminal of the autotransformer to the second supply line, a connection of the second terminal of the autotransformer to the third delta corner terminal, and an additional run capacitor connected between the winding tap and the power source terminal.