Patent ID: 7506711

Claim:
An automotive accessory drive system for a hybrid electric vehicle comprising: an engine; an electric variable transmission operatively connected to the engine, said electric variable transmission including a gear arrangement and at least two motor-generators, said electric variable transmission being configured to selectively produce a plurality of speed ratios; a drive pulley connected to an output shaft of said engine; a plurality of driven pulleys each of which is connected to one of a plurality of accessories; a drive belt connectively coupling said drive pulley and said plurality of driven pulleys and operable to transfer drive forces between said drive pulley and said plurality of driven pulleys; a controller operatively connected to the engine and the electric variable transmission, said controller configured to ensure the plurality of accessories remain adequately powered by selecting a speed ratio adapted to ensure that the speed at which the accessories are driven does not fall below a predefined minimum speed; wherein the engine includes a plurality of intake valves; a plurality of exhaust valves; and a crankshaft; and wherein the controller is configurable to manipulate the intake valves and the exhaust valves when the accessories are being driven by power from the motor-generators through the engine crankshaft, in order to reduce crankshaft rotational resistance and engine pumping losses, and thereby improve the efficiency of the accessory drive system.