Integral self-cleaning filter and side check valve for automatic washer

Claim 1

In an automatic washing machine, means forming a hydraulic circuit, a treatment zone and a pump in said hydraulic circuit for circulating liquid from said treatment zone through said circuit and back to said treatment zone in a fiRst direction and for pumping liquid from said treatment zone through said circuit to a drain in an opposite direction, a self-cleaning filter mounted in said circuit comprising a liquid impervious hollow housing member defining an inlet forming a valve seat and being in liquid communication with said treatment zone, a port in liquid communication with said pump, and a drain outlet, said drain outlet having valve means for allowing fluid flow in one direction only, a filtering member disposed within said housing member and movable to a first position when said pump circulates liquid in said first direction to form a filter maze with said housing member for entrapping foreign particles from the liquid, and movable to a second position when said pump pumps liquid in said opposite direction to sealingly engage said valve seat for closing said inlet to liquid flow while disengaging said filter maze to release foreign particles into the liquid for flow with the liquid through said valve means through said drain outlet, said movement of said filter member being effected by variation in hydraulic pressure within said filter as said port is alternately in communication with the suction and discharge side of said pump.