Line-pulling carriers for conduitthreading apparatus and method of fabrication thereof

Claim 1

FOR USE IN CONJUNCTION WITH A CONDUIT-THREADING APPARATUS, A CARRIER STRUCTURE COMPRISING: (A) A BODY FORMED FROM A POLYFOAM TYPE OF PLASTIC MATERIAL WHICH HAS A COMPRESSIBLE, CELLULAR STRUCTURE AND WHICH IS ADAPTED TO DEFORM AND TO INSTANTANEOUSLY ASSUME THE CROSS-SECTION OF THE CONDUIT THROUGH WHICH THE CARRIER PASSES; (B) SAID BODY COMPRISING AT LEAST ONE CYLINDRICAL PLUG HAVING AN AXIAL BORE FORMED THEREIN; (C) A GROMMET COMPRISING A HOLLOW CYLINDRICAL CORROSION-RESISTANT SLEEVE RECEIVED WITHIN SAID AXIAL BORE; (D) SAID GROMMET BEING AXIALLY COMPRESSED TOGETHER AND HAVING ITS RESPECTIVE ENDS SWAGED OVER, WHEREBY SAID BODY APPROACHES A SUBSTANTIALLY SPHERICAL SHAPE AND ACQUIRES A GREATER DENSITY RADIALLY ADJACENT OF SAID GROMMET, AND WHEREBY AN EASILY-ACCESSIBLE REINFORCED CENTRAL APERTURE IS PROVIDED IN SAID BODY; (E) A POLYPROPYLENE LINE PASSED LOOSELY THROUGH SAID GROMMET WITH RADIAL CLEARANCE THEREBETWEEN; AND (F) MEANS TO SECURE SAID LINE AGAINST REMOVAL THROUGH SAID GROMMET AND FROM SAID BODY.