| 摘要 |
PCT No. PCT/AU94/00558 Sec. 371 Date Mar. 20, 1996 Sec. 102(e) Date Mar. 20, 1996 PCT Filed Sep. 19, 1994 PCT Pub. No. WO95/08690 PCT Pub. Date Mar. 30, 1995A make-up system of a down-the-hole hammer. The down-the-hole hammer is of the type comprising a hammer casing (111) having a top sub (112) mounted to one end and a drill bit chuck mounted to the other end. The casing accommodates a piston which is caused to reciprocate within the hammer casing. The make up system comprises: a fluid flow delivery or valving assembly (121) to be supported at the one end of the hammer casing having an annular flange (117) thereon where the annular flange (117) is capable of being slidably received within the hammer casing (111); an annular recess (122) formed in the wall of the hammer casing (111); a retainer ring (123) supported from the recess (122) and extending inwardly beyond the inner face of the hammer casing (111), the flange (117) being formed with an annular rebate (124) around its perimeter adjacent the inner axial face to define a space between the retainer ring, the flange, and the side wall of the hammer casing, a compressible ring (126) also received in the recess (122) and located in the space, the compressible ring (126) being compressed to fill the space as a result of the clamping forces applied by the fixing of the top sub (112) to the hammer casing (111). |
