US Patent 9938774 Non-rotating drill bit for a down-the-hole drill hammer

A non-rotational drill bit for a down-the-hole drill hammer is provided that includes a head and a shank extending from the head. The head includes a plurality of axisymmetric cutting members about its working face. The drill bit also includes a porting system that includes a central through hole, an air inlet port, an exhaust outlet port and a central exhaust port for exhausting air from an interior of the drill hammer and for clearing drilling debris from the face of the drill bit.