US Patent 7871224 Drill bit and reamer

A tool bit providing a combined drill bit and reamer is disclosed herein. The tool bit comprises an axial bit shaft including a bore end and a shank end. At least one helical land portion is provided on the bit shaft. The at least one helical land portion includes a cutting edge and a trailing edge. At least one reamer blade is provided on the helical land portion at the bore end of the bit shaft. The at least one reamer blade includes a substantially axial cutting edge. A tip arrangement is also included on the bore end of the bit shaft. The tip arrangement includes a center blade positioned between peripheral cutting blades.