Patent ID: 6991051

Claim:
Drive apparatus for a motor vehicle, said apparatus comprising, in combination: (a) first and second DC electric series motors coupled mechanically to rotate together and adapted to be connected mechanically to drive wheels of the motor vehicle, said first motor having a first pair of electrical power terminals and a first shunt field winding, and said second motor having a second pair of electrical power terminals and a second shunt field winding; (b) two input power leads L 1 and L 2 , adapted to be connected to a DC source of electrical power on the motor vehicle; (c) electric switch means for electrically connecting the input power leads L 1 and L 2 to the pairs of first and second power terminals and to the first and second shunt field windings of said motors, said switch means being operative, when in a first mode, to connect the power terminals of the first and second motors in series between the power leads L 1 and L 2 and to disconnect the shunt field windings; operative, when in a second mode, to connect the power terminals of the first and second motors in parallel between the power leads L 1 and L 2 and to disconnect the shunt field windings; and operative, when in a third mode, to connect the power terminals of the first and second motors in parallel and to connect the first and second shunt field windings thereof, to the power leads L 1 and L 2 , whereby the motors operate in a first speed range when the switch means is in said first mode, in a second, higher speed range when the switch means is in said second mode, and in a third highest speed range when the switch means is in the third mode.