Patent ID: 7584626

Claim:
Air-conditioning system for a vehicle, said system comprising: a main internal combustion engine ( 1 ); an alternating current electric machine ( 7 ) suitable to function both as a motor and as a generator; a refrigeration circuit ( 2 ) comprising a compressor ( 3 ), suitable to be driven by said main engine or by said electric machine; a source ( 8 ) of electric power suitable to supply said electric machine; a first clutch ( 10 ) for independently connecting/disconnecting said main engine to said compressor or said compressor to said electric machine; a second clutch ( 11 ) for independently connecting/disconnecting said main engine to said electric machine or to said compressor; and a third clutch ( 12 ) for independently connecting/disconnecting said electric machine to said main compressor or to said main engine; wherein when the first ( 10 ) and the second clutches ( 11 ) are closed, the compressor is driven by the engine ( 1 ) when the vehicle is running; wherein when the first ( 10 ) and the third clutches ( 12 ) closed, the compressor is driven by the electric machine when the vehicle is not running; wherein reducing means ( 13 , 14 , 15 ) are interposed between said main engine ( 1 ), said electric machine and said compressor, said reducing means comprising a first gear ( 14 ) connect to a shaft ( 9 ) of said compressor, a second electric machine ( 7 ), said first ear ( 14 ) being interposed between said second ( 13 ) and said third gear ( 15 ) so as to provide a revolution speed ratio between said engine and said compressor, between said electric machine and said compressor and between said engine and said electric machine.