Patent ID: 7662062

Claim:
A split series-parallel hybrid dual-power drive system operable alternatively as a series power drive system or a parallel power drive system comprising: a first drive system for driving a first load, the first drive system including an engine and a first dynamo-electric unit, the engine having a rotary part coupled to thee first dynamo-electric unit directly or through a first transmission unit; a second drive system for driving a second load; the second drive system including a second dynamo-electric unit, the second load being couple to the second dynamo-electric unit directly or through a second transmission unit; a first clutch provided between and coupled to the engine and the second drive system; a second clutch provided between and coupled to the first dynamo-electric unit and the first load; a rechargeable device coupled to at least one of the first and second dynamo-electric units, the rechargeable device being rechargeable, when at least one of a first and a second load is a light load that is more than a normal load, by power from either the first or the second dynamo-electric unit, the rechargeable device driving at least one of the first and second dynamo-electric units to function as a motor when at least one of the first and second loads is a heavy load that is more than the normal load; and a drive control unit for controlling the first drive system, the second drive system, the first and second clutches, and the rechargeable device; wherein when the system operates as the series power drive system, the first clutch is disengaged so as to prevent a rotational kinetic energy from the engine from being transmitted to the second drive system, the second clutch is also disengaged, so that the engine runs at lower fuel consumption with higher fuel saving so as to reach brake specific fuel consumption, and meanwhile an electric power from the first dynamo-electric unit drives the second dynamo-electric unit via the control unit to drive the second load; wherein when the system operates as the parallel power drive system, the first clutch is engaged so as to allow the rotational kinetic energy from the engine to be transmitted to the second drive system; characterized by a planetary gear set, the planetary gear set including a planet gear that is coupled to the transmission unit, the planetary gear set additionally including a sun gear that meshes with the planet gear and an external gear that also meshes with the planet gear; a dynamo-electrical unit that is coupled to the sun gear; and brake means for selectively immobilizing the external gear.