Quick release down-the-hole hammer drill bit assembly

摘要

A quick release down-the-hole (DTH) hammer drill bit assembly (100) in which a drill bit (105) is releaseably retained at a drive transmission component (drive sub) (110) via a retaining sleeve (123) and respective retaining formations to axially couple and lock the drill bit at the assembly. In particular, the drill bit is retained exclusively at the assembly via retaining formations at the drive sub, the sleeve and the drill bit without a requirement for additional retaining rings that would otherwise axially lock the drill bit at the drive sub.