Fluid check valve

Claim 1

IN A CHECK VALVE, A HOUSING HAVING AN INLET OPENING AND AN OUTLET OPENING, AN INTERNAL SUPPORTING MEMBER IN SAID HOUSING HAVING A CAVITY IN COMMUNICATION WITH THE INLET OPENING OF SAID HOUSING, A FORWARD END PORTION ON SAID SUPPORTING MEMBER IN COMMUNICATION WITH THE OUTLET OPENING OF SAID HOUSING, A CONTINUOUS CIRCULAR GROOVE IN AND AROUND SAID FORWARD END PORTION; SAID GROOVE BEING RECTANGULAR IN CROSS-SECTION AND HAVING A BASE AND OPPOSITE SIDE WALLS, AT LEAST ON PASSAGEWAY IN SAID SUPPORTING MEMBER HAVING ONE END COMMUNICATING WITH THE CAVITY OF SAID SUPPORTING MEMBER AND ITS OTHER END OPERATIVELY COMMUNICATING WITH THE BOTTOM OF SAID GROOVE AND A FLEXIBLE RESILIENT O-RING IN SAID GROOVE IN DIAMETRICALLY YIELDABLE SEALING CONTACT WITH THE BASE OF SAID GROOVE AND BEING SPACED FROM SAID OPPOSITE SIDE WALLS AND HAVING A STRAND WIDTH SUBSTANTIALLY LESS THAN THAT OF THE WIDTH OF SAID GROOVE, SAID O-RING AND SAID GROOVE BEING CENTERED OVER SAID OTHER END OF SAID PASSAGEWAY, AND SAID O-RING GRIPPING THE BOTTOM OF SAID GROOVE SUFFICIENTLY TO RESIST ANY LATERAL MOVEMENT WITHIN SAID GROOVE, AND A SECOND CONTINUOUS CIRCULAR GROOVE HAVING AN INNER EDGE AND AN OUTER EDGE BEING IN THE CENTER BOTTOM OF SAID FIRST GROOVE, SAID SECOND GROOVE HAVING A WIDTH SUBSTANTIALLY LESS THAN THAT OF SAID FIRST GROOVE, AND SAID OTHER END OF SAID PASSAGEWAY BEING IN COMMUNICATION WITH SAID INNER EDGE OF SAID SECOND GROOVE.