Multi-engine drive system for a vehicle

Claim 1

A drive system for a vehicle comprising (a) wheel-carrying first and second axles; (b) a storage battery; (c) a motor/generator selectively operable in motor and generator modes and being connected to said storage battery and cooperating with one of said first and second axles for applying electric energy to said battery when operating in the generator mode and for applying a driving torque to said one of said first and second axles when operating in the motor mode; (d) first and second internal-combustion engines; (e) a transmission connected to the first engine; (f) a first clutch for selectively connecting said transmission to or disconnecting said transmission from, one of said first and second axles; and (g) a second clutch for selectively connecting said second engine to or disconnecting the second engine from, said transmission; and (h) control means for controlling said motor/generator and said first and second internal combustion engines to cause the motor/generator to normally drive the vehicle under normal driving conditions, for causing the first internal combustion engine to supply additional power to drive the vehicle during acceleration and when the motor/generator otherwise cannot supply enough power, and for causing the second internal combustion engine to supply additional power to drive the vehicle when the motor/generator and the first internal combustion engine cannot supply the necessary power for driving conditions: and, wherein said motor/generator has a nominal power less than that of either of said first and second internal combustion engines, and, said second internal combustion engine has a nominal power greater than that of said first internal combustion engine.