Means for stopping the flow of fluid in a conduit

Claim 1

IN MEANS FOR STOPPING THE FLOW OF FLUID IN A CONDUIT, A CARRIER HAVING A DIAMETRICAL SLOT EXTENDING FROM ITS LOWER END PROVIDING TWO SPACED APART ARMS, ONE OF SAID ARMS HAVING A RECESS IN ITS INNER FACE AND EXTENDING FROM ITS LOWER END, A RESTRAINING STRUCTURE MOUNTED IN SAID RECESS AND ANCHORED TO SAID ONE ARM, SAID STRUCTURE BEING EXPANSIBLE TO A FORM APPROXIMATING THE INTERIOR OF THE CONDUIT AND BEING NORMALLY COLLAPSED WITHIN THE WIDTH OF SAID ARMS AND EXTENDING DOWNWARDLY BELOW SAID ARMS, A SOLID RESILIENT PLUG MEMBER OF SUBSTANTIAL THICKNESS SLIDABLE BETWEEN SAID ARMS AND ALONG SAID STRUCTURE IN CLOSE PROXIMITY THERETO, MEANS FOR FORCING SAID CARRIER DOWNWARD EFFECTIVE FOR INITIALLY EXPANDING SAID PLUG MEMBER RADIALLY BY PRESSURE CONTACT WITH THE LOWER INNER PORTIONS OF THE CONDUIT AND ALSO EXPANDING SAID STRUCTURE INTO PRESSURE CONTACT WITH THE INTERIOR OF THE CONDUIT, AND MEANS FOR FORCING SAID PLUG MEMBER DOWNWARD BETWEEN SAID ARMS AND ALONGSIDE OF SAID STRUCTURE FOR FURTHER EXPANDING SAID PLUG MEMBER RADIALLY INTO PRESSURE SEALING CONTACT WITH THE INTERIOR OF THE CONDUIT, SAID RESTRAINING STRUCTURE PRECLUDING DISPLACEMENT OF SAID PLUG MEMBER IN A DIRECTION TOWARD SAID STRUCTURE.