Heat exchanger, in particular for a cooling circuit of a motor vehicle engine

Claim 1

A heat exchanger, particularly for a cooling circuit of a motor vehicle engine, comprising a water box provided with at least a liquid inlet pipe; a nest of tubes opening into the water box; first and second chambers formed inside the water box; first and second liquid circuits formed in parallel in the exchanger, the first circuit comprising said first chamber and at least a portion of said tubes, the second circuit comprising at least said second chamber; passages formed between said liquid inlet pipe, said first chamber and said second chamber and comprising a tubular cylindrical wall forming a bearing open at both ends thereof and extending between said chambers; a valve sensitive to the liquid temperature for controlling the flow of the liquid through said passages and said circuits, a cylindrical valve member guided in said bearing and biased in one direction by said temperature sensitive valve; a return spring for biasing said cylindrical valve member in a direction opposite to said one direction; said temperature sensitive valve, said valve member and said bearing being in axial alignment with said liquid inlet pipe inside said water box, said valve member having an axial inner sleeve and a cylindrical skirt open at both ends thereof and guided in said bearing, said temperature sensitive valve having a body received in said sleeve and a piston applied on a wall of said water box opposite to said liquid inlet pipe, said return spring being provided between said valve member and a wall of said water box.