Liquid filter with built-in pressure regulator

A liquid filter, comprising a housing provided with an inlet connection connected with a dirt side, an outlet connection connected with a clean side, and a tank connection, said housing being composed of a cup-shaped housing element and a cover closing an open end of said housing element;

• a filter element;
• a pressure regulator integrated in said housing at an end side and having a valve so that a liquid flowing over said valve of said pressure regulator when said pressure regulator is actuated flows through said tank connection;
• a diaphragm associated with said pressure regulator, said diaphragm being tightly clamped in said housing and acted upon by a liquid pressure against a spring pressure so as to control said valve of said pressure regulator;
• a spring applying said spring pressure, said pressure regulator being located between said clean side and said tank connection, said diaphragm having a single clamping site on an outer circumference directly in said housing and constituting a moveable closure member in a center, said pressure regulator having a valve seat which is fixed on said housing and with which said moveable closure member cooperates, said diaphragm separating a gas-filled spring chamber from a pressure chamber on which the liquid pressure acts, said valve seat fixed on said housing being connected with said tank connection, said filter element having a double-walled center tube with one end sealingly supported by said pressure regulator and another end sealingly supported on one of said cover and a bottom of said housing element, so that on said clean side an annular chamber connected with said outlet connection is pierced through by a conduit associated with said pressure regulator and provided in said center tube.