Patent ID: 7017563

Claim:
A filter device for purifying a fluid stream comprising a filter housing having an inlet, an outlet, a filter element in said housing sealingly separating the inlet from the outlet, a housing cover, and a pressure relief valve for releasing excess pressure from within said housing, wherein said valve comprising a base body, a valve body, and a biasing means, said base body comprising a valve side and an opposite side situated opposite said the valve side, wherein a part of the valve body protrudes through an opening in the base body, and the biasing means is disposed between the opposite side of the base body and the valve body and supported against said opposite side of the base body, and wherein said valve has a roller diaphragm situated on one side to form a seal with the valve body and on an opposite side to form a seal between the base body and a housing part, said roller diaphragm sealingly separating a control side of said valve from a flow-through side; said control side being connected to an ambient pressure, and said flow-through side being connected to an interior volume of the housing through which the fluid stream flows.