US Patent 8231491 Power output apparatus and hybrid vehicle

A hybrid vehicle includes an engine, motors configured to input and output power, a power distribution integration mechanism, and a transmission. The power distribution integration mechanism has a sun gear connected with one of the motors, a carrier connected with the other motor, and a ring gear connected with the engine. The transmission includes a first speed change mechanism and a second speed change mechanism. The first speed change mechanism has a first speed gear train and a third speed gear train arranged to connect the carrier of the power distribution integration mechanism with a driveshaft. The second speed change mechanism has a parallel shaft-type gear train that is not used alone to set the speed ratio.