Down-the-hole drill drive coupling

摘要

A down-the-hole drill hammer is provided that includes a housing, a piston mounted within the housing, a drill bit mounted below the housing, and a drive coupling operatively engaged with the housing and drill bit. The drive coupling can be configured with a plurality of lugs circumferentially disposed about the drill bit and coupled with the casing for providing rotation thereof. Alternatively, the drive coupling can be configured with segmented lugs configured to circumscribe the drill bit, or as a cylindrical chuck formed out of arch-shaped chuck segments which radially assemble onto the shank of the drill bit.

主权项

1. A down-the-hole drill hammer comprising:
a cylindrical housing; a piston mounted within the housing along a longitudinal direction and configured to reciprocatively move within the housing along the longitudinal direction; a drill bit assembly disposed completely below the housing, the drill bit assembly including:
a head,a shank extending from the head;a plurality of shank splines circumferentially spaced about the shank; and a drive coupling engaging the housing and the drill bit assembly, the drive coupling including a chuck assembly connected to a distal end of the housing, the chuck assembly including: a plurality of chuck segments each having:
a proximal end that includes a connector for connecting to the housing,a distal end configured to receive the shank, anda plurality of chuck splines each configured to engage one of the plurality of shank splines.