Patent ID: 7267084

Claim:
A cooling and heating device for an internal combustion engine ( 6 ) which has coolant inlet ports ( 4 , 5 ) and a coolant return port ( 10 ), said device comprising a main coolant pump ( 1 ) for supplying a coolant to the internal combustion engine ( 6 ) via the coolant inlet ports ( 4 , 5 ), a first flow control unit ( 3 ) for controlling the coolant flow to the coolant inlet ports ( 4 , 5 ), a second flow control unit ( 17 ) arranged in a coolant return line ( 10 ) from the engine ( 6 ), said second flow control unit ( 17 ) directing the coolant, depending on the temperature thereof, to an inlet of the main coolant pump ( 1 ) either via a large cooling circuit ( 20 ) including an air/fluid cooler ( 21 ) or via a small cooling circuit ( 18 ) bypassing the air/fluid cooler ( 21 ), a transmission oil heat exchanger ( 24 ) through which both the coolant and transmission oil flow and a third coolant flow control unit ( 27 ) for controlling the coolant flow through the transmission oil heat exchanger in order to heat the transmission oil in the transmission oil heat exchanger ( 24 ), a coolant flow conduit extending from the return flow line ( 10 ) of the internal combustion engine ( 6 ) through the transmission oil heat exchanger ( 24 ) for heating the transmission oil and a coolant line extending from a return flow opening of a low-temperature region ( 23 ) of the air/fluid cooler ( 21 ) to the transmission oil heat exchanger ( 24 ) for transferring heat from the transmission oil to the coolant, said third flow control unit ( 27 ) directing the flow of coolant through the transmission oil heat exchanger ( 24 ) starting from a predefined coolant temperature for heating the transmission oil when the engine is warmed up and directing coolant from the low temperature region ( 23 ) of the air/fluid cooler ( 21 ) through the transmission oil heat exchanger ( 27 ) when the transmission oil needs cooling, and said third flow control unit ( 27 ) further including a valve disk ( 26 ) with a bypass bore ( 34 ) through which, in a cooling phase, a limited amount of coolant returning from a heating circuit line ( 12 ) is permitted to flow back to the main coolant pump ( 1 ), while the flow control unit ( 27 ) directs the coolant flows from the low temperature region ( 23 ) of the air/fluid cooler ( 21 ) via the transmission oil heat exchanger ( 24 ) back to the main coolant pump ( 1 ).