Patent ID: 6494276
Filing Date: 2002-12-17
Classification: E21B,Y10T

Abstract:
A rock auger comprising:a cylindrical hollow cutting head for removing plugs of hard material from post holes comprising a hollow cylindrical body defining side walls connecting to an end plate, said hollow cylindrical body defining an upper peripheral edge and a lower open end defining a lower peripheral cutting edge including a plurality of removable teeth extending from said lower peripheral edge; said end plate extending across said hollow cylindrical body joining said side walls and covering at least a portion thereof; a drive shaft having a diameter less than said cutting head, said drive shaft including a proximal end connecting to a top surface of said end plate and having an opposing distal drive end extending therefrom; means for connecting said distal drive end of said shaft to a drive shaft of a power unit; and a pilot drill bit including a pilot drill bit shaft and tip disposed within said cylindrical hollow cutting head, said pilot drill bit shaft mounting to a bottom surface of said mounting end plate.