Filter unit with by-pass and anti-drain back valve

Claim 1

A SPIN-ON TYPE OIL FILTER UNIT COMPRISING A HOUSING WITH A CLOSURE MEMBER HAVING AN OIL INLET AND OIL OUTLET THEREIN, AN ANNULAR FILTER ELEMENT IN SAID HOUSING, AND A BY-PASS AND ANTI-DRAIN BACK VALVE ASSEMBLY DISPOSED IN SAID HOUSING INCLUDING SLEEVE MEANS WITH A FILTER ELEMENT SUPPORT MEMBER, OUTER CASING MEANS DISPOSED ON SAID SUPPORT MEMBER FORMING AN ANTI-DRAIN BACK CHAMBER, SAID FILTER ELEMENT SEATED ON SAID SUPPORT MEMBER AROUND SAID OUTER CASING MEANS, OIL INLET PORT MEANS IN SAID OUTER CASING MEANS, AN ANTI-DRAIN BACK VALVE POSITIONED TO COVER SAID OIL INLET PORT MEANS, BIASING MEANS IN SAID CHAMBER URGING SAID VALVE TO A SEATED POSITION, AN INNER CASING MEANS ON SAID SUPPORT MEMBER COMMUNICATING AT THE TOP THEREOF WITH SAID OUTER CASING MEANS AND DISPOSED WITHIN SAID OUTER CASING MEANS AND FORMING A BY-PASS CHAMBER INWARDLY OF SAID ANTI-DRAIN BACK CHAMBER, BY-PASS OIL PORT MEANS IN SAID SUPPORT MEMBER, A BY-PASS VALVE COVERING SAID BY-PASS PORT MEANS, SEPARATE BY-PASS BIASING MEANS URGING SAID BY-PASS VALVE TO A SEATED POSITION, SAID BY-PASS VALVE BEING DISPOSED WITHIN SAID INNER CASING MEANS AND IN SAID BY-PASS CHAMBER.