Patent ID: 6991054

Claim:
A hybrid vehicle drive system including an internal combustion engine, a first motor generator, and a second motor generator, the system comprising: a power distribution device; an output shaft of the internal combustion engine is coupled to the first motor generator via the power distribution device, the output shaft is also coupled to a first portion of a wheel drive shaft via the power distribution device, the wheel drive shaft being connected to the second motor generator; a torque increasing device that increases a torque of the wheel drive shaft separately from the second motor generator so as to enhance cranking of the internal combustion engine performed by the first motor generator via the power distribution device; and a clutch on an intermediate portion of the wheel drive shaft, the clutch dividing the wheel drive shaft into the first portion closest to the torque increasing device and a second portion closest to the wheels, wherein: the second motor generator is connected to the second portion of the wheel drive shaft, and a function of the clutch is obtained by a clutch function of a transmission provided on the wheel drive shaft of the hybrid vehicle.