Patent ID: 7424869

Claim:
A cooling circuit for an internal combustion engine of a motor vehicle, the cooling circuit comprising: the internal combustion engine ( 10 ) having a coolant inlet side and a coolant outlet side, a pump device ( 12 ) arranged upstream of the internal combustion engine ( 10 ) with an inlet and an outlet connected to the coolant inlet side of the internal combustion engine ( 10 ) for pumping a coolant through the internal combustion engine ( 10 ), a cooler ( 14 ) connected by means of a first coolant line ( 18 ) to the outlet side of the internal combustion engine ( 10 ) and by means of a second coolant line ( 20 ) to the inlet of the pump device ( 12 ), a cooler bypass line ( 22 ) extending between the outlet side of the internal combustion engine ( 10 ) and the inlet of the pump device ( 12 ) while bypassing the cooler ( 14 ); and a switching valve ( 24 ), arranged in the second coolant line ( 20 ) between the cooler ( 14 ) and the pump device ( 12 ) for selectively opening and closing the second coolant line ( 20 ), the cooler bypass line ( 22 ) being also connected to the switching valve ( 24 ) to be controlled thereby, switching valve bypass line ( 44 ) extending between the second coolant line ( 20 ) and the inlet of the pump device ( 12 ) while bypassing the switching valve ( 24 ) and a valve device ( 46 ) arranged in the switching valve bypass line ( 44 ), which valve device ( 46 ), when activated, prevents a return flow of the coolant from the inlet of the pump device ( 12 ) to the second coolant line ( 20 ) at all times but which is inactivated so as to be open when the engine is shut down, thereby providing for direct connection between the second cooling line ( 20 ) and the inlet of the pump device ( 12 ).