Patent attributes
A flow diversion sub for a down-the-hole drill comprising a housing assembly that includes a housing body, a cap extending from the housing body, and a drive shaft having an upper central blind hole and a lower central blind hole spaced from the upper central blind hole, wherein the drive shaft is received within the housing assembly. In operation, one of the housing assembly and drive shaft moves between a first position and a second position relative to the other of the housing assembly and drive shaft. In the first position the upper central blind hole is in fluid communication with the lower central blind hole, and in the second position the upper central blind hole is blocked from being in fluid communication with the lower central blind hole.
