Drill Rod

Abstract

According to the present invention, a drill rod ( 10 ) comprises an elongate hollow shaft ( 12 ) with a first shaft end and a second shaft end ( 22 ), the first shaft end having a first connector for connecting the drill rod ( 10 ) to a drive mechanism, the second shaft end ( 22 ) having a first female tread ( 24 ); and an adapter ( 30 ) with a first adapter end ( 32 ) and a second adapter end ( 34 ), the first adapter end ( 32 ) having a first male thread ( 42 ) cooperating with the first female tread ( 24 ) of the second shaft end ( 22 ), the second adapter end ( 34 ) having a second connector for connecting a drill bit ( 46 ) thereto. When a drill bit ( 46 ) is connected to the drill rod ( 10 ), the adapter ( 30 ) is sandwiched between the hollow shaft ( 12 ) and the drill bit ( 46 ). The above configuration of drill rod allows a great variety of drill bits to be used in conjunction with a single hollow shaft. There is hence no need to provide a different hollow shaft if a different drill bit is to be used. Manufacturing costs of drill rods do hence not have to be considerably-increased if a variety of drill bits are to be used.

1 . A drill rod comprising:
 an elongate hollow shaft with a first shaft end and a second shalt end, said first shaft end having a first connector configured so as to connect said drill rod to a drive mechanism, said second shaft end having a first female tread; and   an adapter with a first adapter end and a second adapter end, said first adapter end having a first male thread cooperating with said first female tread of said second shaft end, said second adapter end having a second connector for connecting a drill bit thereto;   wherein, when a drill bit is connected to said drill rod, said adapter is sandwiched between said hollow shaft and said drill bit;   wherein said adapter comprises a fluid conduit extending from said first adapter end to said second adapter end; and   wherein said adapter comprises a plurality of orifices in its circumferential wall, said orifices being fluidly connected to said fluid conduit.   
   
   
       2 . The drill rod according to  claim 1 , wherein said drill rod further comprises a drill bit with a third connector cooperating with said second connector of said second adapter end. 
   
   
       3 . The drill rod according to  claim 2 , wherein said second connector of said second adapter end comprises a second male thread and said third connector of said drill bit comprises a second female tread cooperating with said second male thread of said second connector of said second adapter end. 
   
   
       4 . The drill rod according to  claim 1 , wherein said orifices are arranged in said second adapter end. 
   
   
       5 . The drill rod according to  claim 1 , wherein said adapter comprises a check valve arranged in said fluid conduit between said first adapter end and said orifices. 
   
   
       6 . The drill rod according to  claim 1 , wherein said adapter comprises a collar between said first male thread of said first adapter end and said connector of said second adapter end, said collar having a diameter larger than the diameter of said first and second adapter ends and wherein said orifices are arranged in said collar. 
   
   
       7 . The drill rod according to  claim 6 , wherein said collar comprises a chamfered portion with a diameter decreasing in direction of said first adapter end, and wherein said orifices are arranged in said chamfered portion of said collar. 
   
   
       8 . The drill rod according to  claim 1 , wherein in said adapter comprises a check valve arranged in said fluid conduit.