Down-the-hole drill hammer having a coaxial accumulator

Abstract

A down-the-hole drill hammer comprising a housing, a backhead connected to the housing, an accumulator housed within the housing and downstream the backhead, and a piston reciprocally mounted within the housing. The accumulator includes an accumulator housing, a liner within the accumulator housing, and a flexible diaphragm circumscribing the liner and within the accumulator housing.

I/We claim: 
     
         1 . A down-the-hole drill hammer comprising:
 a housing; and   an accumulator housed within the housing, the accumulator including:
 a liner, and 
 a diaphragm circumscribing the liner. 
   
     
     
         2 . The down-the-hole drill hammer of  claim 1 , wherein the diaphragm is a flexible diaphragm. 
     
     
         3 . The down-the-hole drill hammer of  claim 1 , wherein the diaphragm hermetically seals the liner. 
     
     
         4 . The down-the-hole drill hammer of  claim 1 , wherein the diaphragm is cylindrical. 
     
     
         5 . The down-the-hole drill hammer of  claim 1 , wherein the diaphragm includes annular protrusions operable to seal against the liner. 
     
     
         6 . The down-the-hole drill hammer of  claim 1 , wherein the accumulator further comprises an accumulator housing for housing the liner and diaphragm. 
     
     
         7 . The down-the-hole drill hammer of  claim 1 , wherein the accumulator is completely housed within the housing. 
     
     
         8 . The down-the-hole drill hammer of  claim 1 , wherein the accumulator is completely housed within a proximal end of the housing. 
     
     
         9 . The down-the-hole drill hammer of  claim 1 , further comprising supply ports housed within the housing and wherein the accumulator is adjacent the supply ports. 
     
     
         10 . The down-the-hole drill hammer of  claim 1 , further comprising a piston housed within the housing and wherein the accumulator is upstream the piston. 
     
     
         11 . The down-the-hole drill hammer of  claim 1 , further comprising a backhead connected to the housing and wherein the accumulator is downstream the backhead. 
     
     
         12 . The down-the-hole drill hammer of  claim 1 , wherein the liner includes a plurality of radially-directed apertures. 
     
     
         13 . The down-the-hole drill hammer of  claim 1 , further comprising a charge valve housed within the housing for supplying a compressible fluid to the accumulator. 
     
     
         14 . A down-the-hole drill hammer comprising:
 a housing;   a backhead connected to the housing;   an accumulator housed within the housing and downstream the backhead, the accumulator including:
 an accumulator housing, 
 a liner within the accumulator housing, and 
 a flexible diaphragm circumscribing the liner and within the accumulator housing; and 
   a piston reciprocally mounted within the housing.