US Patent 7815054 Filter device

A filter device includes at least one filter element (10) housed in a filter housing (22) and connected for the flow of fluid by fluid connections (30, 36) to a fluid device, in particular in the form of a hydraulic tank (40), using a connector device (44). A plunger valve arrangement is achieved, whereby the connector device (44) is provided with at least one longitudinally-displaceable blocking piece (46). In the blocking position, the blocking piece blocks the provided fluid connections (30, 36). After displacement into an open position, it releases the fluid connections. A blocking or releasing of the fluid connections in a rapid operation process is permitted to carry out a filter element exchange for the used filter medium.