Patent ID: 6698537
Filing Date: 2004-03-02
Classification: E21B,Y10T

Abstract:
A percussion bit assembly for connection to a drill string for earth boring operations comprising:a substantially tubular housing having a lower end portion; a substantially tubular chuck member having upper and lower portions and upper and lower ends, the upper portion of the chuck member being mountable to the lower end portion of the housing; a percussion bit having a shank and a head, wherein at least a part of the shank is disposed within the chuck member and the head is disposed below the lower end of the chuck member, the shank including a radially extending shoulder having an outside diameter; a substantially cylindrical retainer member supported by the chuck member having upper and lower ends, inwardly extending, substantially annular, upper and lower lips, a middle portion longitudinally extending between the upper and lower lips, and a plurality of slots extending from the lower end of the retainer member to a terminal end disposed intermediate the upper and lower ends, the lower lip having an inside diameter which is less than the outside diameter of the shoulder, the slots defining a plurality of longitudinally extending cantilever beam segments, the percussion bit being connected to the chuck member by inserting the shoulder of the percussion bit into the middle portion of the retainer member, the cantilever beam segments being resiliently, radially deflected by the shoulder of the percussion bit.