Filter unit with anti-drain back valve means

Claim 1

A SPIN-ON THROWAWAY TYPE OIL FILTER UNIT COMPRISING A HOUSING WITH A CLOSURE MEMBER CLOSING OFF ONE END HAVING A CENTRAL OPENING THEREIN FORMED BY A THREADED NIPPLE FOR SCREWING ONTO AN ENGINE AND DISCHARGING OIL THERETHROUGH, OIL INLET MEANS IN SAID CLOSURE MEMBER SURROUNDING SAID NIPPLE, AND A FILTER SUPPORT MEMBER MOUNTED ON SAID NIPPLE FORMING A UNITARY STRUCTURE PROVIDED WITH AN ANTI-DRAIN BACK VALVE AND BY-PASS VALVE, SAID SUPPORT MEMBER INCLUDING A FIRST SLEEVE WITH A SUBSTANTIALLY HORIZONTAL ANNULAR RIM, AN ANNULAR FILTER ELEMENT WITH A CENTER TUBE SEATED ON SAID RIM, ANOTER UPWARDLY EXTENDING SLEEVE SECURED TO SAID RIM AND EXTENDING INTO SAID CENTER TUBE, BY-PASS PORT MEANS IN SAID RIM, A BY-PASS VALVE SEATED OVER SAID PORT MEANS AND OR SAID RIM, BIASING MEANS NORMALLY URGING SAID BY-PASS VALVE SEATED AGAINST SAID RIM, THE UPPER END OF SAID UPWARDLY EXTENDING SLEEVE HAVING A CENTRAL OPENING, A RESILIENT ANIT-DRAIN BACK VALVE SECURED TO SAID UPPER END OF SAID UPWARDLY EXTENDING SLEEVE AROUND ITS CENTRAL OPENING, SAID ANTI-DRAIN BACK VALVE HAVING A DEPENDING CYLINDRICAL UPPER PORTION DISPOSED WITHIN SAID UPWARDLY EXTENDING SLEEVE AND A CONVERGING LOWER PORTION EXTENDING DOWNWARDLY THEREFROM AND CONVERGING TO A POSITION LOCATED CENTRALLY OF AND SUBSTANTIALLY AT THE SAME LEVEL AS SAID RIM.