Apparatus for forming holes in sewer mains

Claim 1

IN AN APPARATUS FOR CUTTING A CIRCULAR HOLE IN A SIDE OF A CIRCULAR UNDERGROUND SEWER PIPE COMPRISING: (A) A CUTTER SUPPORT INCLUDING AN ELONGATED PLATE HAVING OPPOSED FACES AND AN OPENING THEREIN, (B) A HOUSING SECURED TO SAID PLATE AT ONE FACE THEREOF IN SURROUNDING RELATIONSHIP TO SAID OPENING AND EXTENDING OUTWARDLY THEREFROM, (C) A CUTTER SHAFT EXTENDING THROUGH SAID OPENING AND HOUSING, (D) BEARING MEANS WITHIN SAID HOUSING MOUNTING SAID CUTTER SHAFT FOR ROTATION ABOUT ITS LONGITUDINAL AXIS AND FOR RECIPROCAL MOVEMENT TOWARD AND AWAY FROM SAID PIPE, (E) A CUTTER SECURED TO SAID CUTTER SHAFT AND DISPOSED BETWEEN SAID PLATE AND SAID PIPE, (F) AT LEAST TWO PAIRS OF LEGS SECURED TO SAID PLATE AND EXTENDING GENERALLY PERPENDICULARLY OUTWARDLY FROM THE OPPOSITE OF SAID FACES, (G) EACH OF SAID LEGS HAVING A PIPE-ENGAGING FOOT EXTENDING LATERALLY THEREFROM GENERALLY TANGENTIALLY TO SAID SIDE OF SAID CIRCULAR PIPE, (H) TWO LINK CHAINS, EACH INTERCONNECTING THE FEET OF CORRESPONDING PAIRS OF LEGS FOR HOLDING THE FEET AGAINST SAID SIDE OF SAID PIPE, (I) A COIL SPRING CONNECTING ONE END OF EACH CHAIN TO THE FOOT ON ONE LEG OF EACH PAIR; THE IMPROVEMENT IN MEANS FOR TIGHTENING SAID CHAINS AGAINST SAID PIPE COMPRISING A QUICK RELEASE COUPLING ATTACHED TO THE OPPOSITE END OF EACH CHAIN COMPRISING: (A) HOOK MEANS FOR INSERTION INTO A HOLE IN THE FOOT ON THE OTHER LEG OF EACH PAIR OF LEGS, AND (B) LEVER MEANS CONNECTING EACH HOOK MEANS TO ONE OF SAID CHAINS, SAID LEVER MEANS BEING PIVOTED OFF-CENTER FOR QUICKLY MOVING SAID HOOK MEANS TOWARD AND AWAY FROM SAID HOLE.