Venting closure for containers

Claim 1

IN A CONTAINER STRUCTURE, A TUBULAR FLANGE DEFINING AN OPENING IN THE CONTAINER AND CONSTITUTED OF FLEXIBLE ELASTOMERIC MATERIAL AND HAVING A SEATING SURFACE AT ITS UPPER END, A CUP-SHAPED SEALING MEMBER CONSTITUTED OF FLEXIBLE ELASTOMERIC MATERIAL AND HAVING AT ITS UPPER END AN OUTWARDLY EXTENDING FLANGE SEATED ON SAID TUBULAR FLANGE SEATING SURFACE TO SUPPORT SAID MEMBER IN DEPENDING RELATIONSHIP WITHIN SAID TUBULAR FLANGE, THE BODY OF SAID SEALING MEMBER BEING OF TUBULAR CONFIGURATION WITH AN INNER AND OUTER SIDE WALL AND A BOTTOM WALL, SAID OUTER WALL BEING CONSTITUTED OF A CONTINUOUS LAYER OF ELASTOMERIC MATERIAL, AND SAID INNER SIDE WALL BEING CONSTITUTED OF SPACED RIBS PROJECTING INWARDLY FROM AND EXTENDING UP THE OUTER WALL AND OVER THE OUTWARDLY EXTENDING FLANGE, SAID OUTER WALL AT ITS UPPER PORTION BEARING AGAINST THE INTERIOR SURFACE OF SAID TUBULAR FLANGE WITH SUFFICIENT PRESSURE TO PROVIDE A GAS TIGHT AND LIQUID TIGHT SEAL, A CLOSURE CAP CONSTITUTED OF ELASTOMERIC MATERIAL AND HAVING AN OUTER DEPENDING WALL COUPLED TO SAID TUBULAR FLANGE, SAID CLOSURE CAP HAVING AN INWARDLY TAPERED WALL PORTION ENGAGEABLE WITH THE INNER PERIPHERAL UPPER EDGES OF THE SPACED RIBS ON SAID SEALING MEMBER TO NORMALLY HOLD SUCH FLANGE SEATED IN SEALING RELATION ON SAID TUBULAR FLANGE SEATING SURFACE, AND THE EXTERIOR SURFACE OF THE LOWER PORTION OF SAID SEALING MEMBER BEING SPACED FROM SAID INTERIOR SURFACE OF THE TUBULAR FLANGE TO PERMIT GAS OF HIGH PRESSURE TO ENTER BETWEEN SAID BODY AND SAID INTERIOR SURFACE AND FLEX THE PORTIONS OF SAID OUTER WALL OF THE BODY BETWEEN THE RIBS AWAY FROM THE INTERIOR SURFACE AND THE SEATING SURFACE OF SAID FLANGE THEREBY PERMITTING THE GAS TO ESCAPE PAST THE UPPER PORTION OF THE SEALING MEMBER.