Abstract: A filter device for removing fine particles in the fluid line, such as in a power steering system including a housing having an inlet body wall and an outlet body wall connecting respectively with an inlet tube and an outlet tube. A perforated support plate has a valve seat formed around a central opening and is mounted between the inlet body wall and the outlet body wall for separating the housing interior into an inlet chamber and an outlet chamber. The valve seat and a boss on the inlet body wall form a filter relief valve. A filter disc, made of a soft flexible material, is located in intimate contact with the support plate on the inlet chamber side of such plate for filtering the particles from the inlet fluid prior to the passage of the fluid through the filter disc and the holes in the support plate into the outlet chamber.

Abstract: A filter device for use in the return line of a power steering system for filtering the fine metal particles in the power steering fluid, thereby minimizing contamination, reducing friction and maintaining normal fluid temperatures. A perforated support plate is mounted between an upper body wall and a lower body wall for separating the housing interior into an inlet chamber and an outlet chamber. A felt filter disc is located in intimate contact with the support plate on the inlet chamber side of such plate for filtering the particles from the inlet fluid prior to the passage of the fluid through the filter and the holes in the support plate into the outlet chamber. A relief valve is provided by the combination of the aligned central opening in both the support plate and the adjacent filter disc together with a boss in the upper body wall which extends into such central opening in sealing engagement against the filter material for closing off the relief valve opening under normal filtering conditions.