Abstract: A DHD hammer that can exhaust working air volumes partially through a proximal end of the DHD hammer's actuator assembly includes a drive chamber, a return chamber, and a backhead that includes exhaust ports. Working air volumes from the drive chamber are exhausted through the backhead while working air volumes from the drive chamber are exhausted primarily through a drill bit.

Abstract: A washer device is provided for a threaded joint formed between two members, preferably two down-hole drill components, each member having a threaded portion and an end surface, the two member threaded portions being engaged to couple the two members such that the two end surfaces generally face each other. The washer device basically includes a generally annular body having a central axis and opposing axial ends. The body is formed of a flexible strip having two opposing ends, the flexible strip being winded about the axis into at least one complete loop with one of the two ends being attached to either an intermediate portion of the strip or the other one of the two strip ends. The annular body is disposable between the two members such that each joint member end surface is disposable against a separate one of the washer body axial ends.

Abstract: A fluid channeling device (10) is for a down-hole drill assembly (1) having a central axis (1c) and advanceable into a hole in a downward direction (D) along the axis (1c). The assembly (1) includes a drill member (2) with an inner surface (2a) bounding a central bore (2b) and an outer surface (2c). The channeling system includes at least one passage (12) provided within the drill member (2) so as to extend generally between the drill member inner (2a) and outer surfaces (2c). A generally annular channeling member (14) is disposeable about a portion of the drill member (2) and has at least one inlet port (20), at least one discharge port (16), and a passage (12) extending between the inlet (20) and discharge ports (16). The inlet port (20) is fluidly connectable with the drill member passage (12) to fluidly couple the central bore (2b) with the discharge port (16).

Abstract: A fluid distributor device is for a percussive drill assembly including a generally tubular casing (2) having a longitudinal centerline and a piston (6) disposed within the casing so as to define a reservoir chamber (27) in the casing. The distributor device comprises a generally cylindrical body (12) disposed within the casing and including a central axis, two opposing ends spaced apart along the axis, first and second interior chambers and a port fluidly connecting the two chambers. The body further has a plurality of fluid passages extending between the two ends and fluidly connecting the first chamber with the reservoir chamber and a deflectable retainer portion (16) releasably engaged with the casing so as to retain the body at a desired position with respect to the casing centerline. A valve (7) is disposed within the body and is configured to permit fluid flow through the port and to alternatively prevent fluid flow through the port.