Patent ID: 7757960

Claim:
A thermostat valve for a cooling system of a combustion engine, comprising: a valve housing defining a valve seat; a valve member biased by a spring against the valve seat; a thermal extension element within the valve housing which acts on the valve member opposite to the spring, wherein the valve member comprises an annular member having an inner annular sealing portion and a first outer annular sealing portion biased by the spring against the valve seat; and a tappet component having a second outer annular sealing portion which, in a closed position of the tappet component, is pressed against the inner annular sealing portion of the annular member, wherein the tappet component cooperates with the thermal extension element to configure a passage between the inner sealing portion of the annular member and the second outer sealing portion of the tappet component in an initial movement of the tappet component by the thermal extension element, and the annular member is co-moved with the tappet component and lifted from the annular valve seat in a further movement of the tappet component; the annular member further comprises two annular discs and an annular sealing element which is sandwiched between the two annular discs, and the inner annular sealing portion and the first outer annular sealing portion are defined by sections of the annular sealing element which are exposed along inner and outer peripheries, respectively, of the two annular discs.