Valve construction with hollow resilient sealing means

Claim 1

IN A VALVE CONSTRUCTION, A VALVE BODY MEMBER HAVING A SEAT, A VALVE CLOSURE MEMBER COOPERATING WITH SAID SEAT IN ITS CLOSED POSITION, SAID MEMBERS BEING SPACED APART WITH A SLIGHT GAP IN THE CLOSED POSITION OF SAID VALVE, ONE OF SAID MEMBERS BEING PROVIDED WITH A GROOVE HAVING PARALLEL, UNRECESSED SIDE WALLS AND A BOTTOM WALL, THE OTHER OF SAID MEMBERS EXTENDING ACROSS THE MOUTH OF SAID GROOVE IN THE CLOSED POSITION OF SAID VALVE MEMBER, A SEALING MEANS OF RESILIENT MATERIAL DISPOSED IN SAID GROOVE, SAID SEALING MEANS HAVING A BASE OF SUFFICIENT WIDTH GREATHER THAN THE DISTANCE BETWEEN SAID SIDE WALLS OF THE GROOVE AS TO REQUIRE DEFORMATION OF SAID SEALING MEANS INTO TIGHT CONTACT WITH SAID SIDE WALLS, SAID SEALING MEANS FORMED WITH AN ANNULAR ARCHED WALLS, PORTION DISPOSED PROJECTING OUT OF SAID GROOVE, SAID ARCHED WALL PORTION ENCLOSING A HOLLOW SPACE WITHIN THE SAME, AT LEAST A SUBSTANTIAL PORTION OF SAID HOLLOW SPACE BEING LOCATED WITHIN THE CONFINES OF SAID GROOVE, THE SIDES OF SAID GROOVE BEING FARTHER APART THAN THE WIDTH OF SAID ARCHED WALL PORTION IN UNSTRESSED CONDITION OF SAID SEALING MEANS, SAID ARCHED WALL PORTION BEING FREE TO FLEX WITHIN THE GROOVE AND DISPOSED TO CONTACT AND FORM A FLUID TIGHT SEAL WITH RESPECT TO SAID OTHER MEMBER, SAID ARCHED WALL PORTION SURROUNDING SAID HOLLOW SPACE ACCOMMODATING VARIATIONS IN WIDTH OF SAID GAP IN RESPONSE TO APPLIED FLUID PRESSURE DIFFERENTIALS IN SAID VALVE.