Pipeline plugger

Claim 1

A PIPE PLUGGER OF THE TYPE HAVING A PLUG MEANS INSERTABLE INTO A PIPE THROUGH A SIDE OPENING IN THE PIPE, COMPRISING A HOUSING MOUNTABLE AT ONE SIDE OF THE PIPE TO PROVIDE A FLUID TIGHT CLOSURE COMMUNICATING WITH SAID SIDE OPENING, PLUG MEANS ADAPTED TO BE MOVED FROM THE HOUSING THROUGH THE SIDE OPENING INTO THE PIPE AND THEN LATERALLY THEREIN TO PROVIDE A FLUID BARRIER ACROSS THE PIPE TO ONE SIDE OF SAID SIDE OPENING, A SHAFT RIGIDLY CONNECTED TO THE PLUG MEANS AND HAVING A LENGTH ROUND IN CROSS-SECTION EXTENDING THROUGH A CIRCULAR OPENING IN A WALL OF THE HOUSING, AN ANNULAR GROOVE IN THE WALL OF THE OPENING INTERMEDIATE THE ENDS OF THE OPENING, THE WALLS OF THE OPENING FLARING ON EITHER SIDE OF THE GROOVE SO THAT THE SIZE OF THE OPENING ADJACENT THE OUTER SIDE WALL OF THE GROOVE IS SUCH THAT THE ROD IS CLOSELY EMBRACED AT SUCH POINT WHILE THE SIZE OF THE OPENING AT OTHER POINTS ALONG THE WALLS OF THE OPENING IS LARGER THAN THE SIZE OF THE ROD TO PERMIT THE ROD TO BE ROCKED WHILE BEING CLOSELY EMBRACED BY THE WALLS OF SAID OPENING ADJACENT SAID GROOVE, AND A RESILIENT SEAL RING IN SAID GROOVE PROVIDING A SEAL BETWEEN THE ROD AND SAID HOUSING.