Fastener protective sealing means

Claim 1

A FASTENER COMPRISING AN ELONGATED SHANK HAVING A CENTRAL AXIS, AN INTEGRAL ENLARGED HEAD ADAPTED TO BEAR AGAINST AN OBJECT TO EXERT AN AXIAL FORCE AGAINST IT, THEREBY TO HOLD THE OBJECT ASSEMBLED TO ANOTHER OBJECT, THE HEAD HAVING A TOP SURFACE ON THE OPPOSITE SIDE THEREOF FROM THE SHANK, AND A PERIPHERY COAXIAL WITH THE SHANK, AT LEAST A PORTION OF WHICH IS A SURFACE OF REVOLUTION SPACED FROM THE HEAD END OF THE FASTENER, SAID HEAD HAVING A PERIPHERAL GROOVE CONTIGUOUS TO THE HEAD END AND TO THE SURFACE OF REVOLUTION, AND OPEN AT THE HEAD END, AND A PERIPHERAL SEALING RING OF DEFORMABLE MATERIAL BONDED IN SAID GROOVE HAVING AN END SURFACE AT SAID HEAD END AND A SIDE SURFACE, SAID SIDE SURFACE STANDING OUTWARDLY OF THE SAID SURFACE OF REVOLUTION AT THE HEAD END, THE END SURFACE OF THE RING BEING OPEN AT THE TOP SURFACE OF THE ENLARGED HEAD, AND THE END SURFACE AT THE HEAD END AND THE SIDE SURFACE OF THE SEALING RING BOTH BEING UNCONFINED, WHEREBY WHEN THE SHANK IS PASSED THROUGH A HOLE IN A BODY AND THE HEAD ENTERS AN ENLARGED BODY OPENING CONCENTRIC WITH SAID HOLE, WHICH ENLARGED BODY OPENING IS OF GENERALLY THE SAME SHAPE AS SAID SURFACE OF REVOLUTION, THE STANDING OUTWARDLY PORTION OF THE SEALING RING MAKES CONTACT WITH THE WALL OF THE ENLARGED BODY OPENING TO FORM A SEAL BETWEEN THE HEAD AND THE BODY AT THE HEAD END OF THE FASTENER, THEREBY PROTECTING THE SURFACE OF REVOLUTION AND THE SHANK FROM FLUID SEEPAGE FROM THE HEAD END.