Patent ID: 6681871
Filing Date: 2004-01-27
Classification: E21B,Y10T

Abstract:
A tool for boring comprising:a) a first shaft for drivingly linking at a first end to a portable rotatable machine, said first shaft having an axis defining a longitudinal axis of rotation; b) a second shaft drivingly linked to said first shaft, said second shaft having a fastener to which a modular auger section can be drivingly linked, and an outer surface to which a radially inwardly extending edge of a helical flight is attached; c) a cylindrical collar having an outer surface and an inner surface, said inner surface mounted to a radially outwardly extending peripheral edge of said helical flight, and said collar mounted radially outwardly of said second shaft; d) means for electrically insulating said first shaft from said second shaft interposed between the first and second shaft; and e) mechanical release means drivingly linked to said shafts for rotatably unlinking said shafts upon the application of a predetermined amount of relative torque to said shafts.