Anchoring device

Abstract

In an anchoring device, a drill head and expansion element(s) are configured to cooperatively interlock with each other to provide for directed movements of the drill head relative to a longitudinal axis of the shaft. Co-operating contact surfaces between the drill head and the expansion element(s) are configured such that relative longitudinal movement of the drill head with respect to the expansion element(s) displace(s) the expansion element(s) outwardly so the expansion element(s) can provide frictional contact with a borehole once inserted therein.

1 . An anchoring device including:
 a drilling assembly including an elongate shaft with a drill head at one end, and another end configured to connect to a drilling apparatus; and   at least one expansion element;   characterised in that   the drill head and expansion element(s) are configured to cooperatively interlock with each other to provide for directed movements of the drill head relative to a longitudinal axis of the shaft;   wherein   co-operating contact surfaces between the drill head and the expansion element(s) are configured such that relative longitudinal movement of the drill head with respect to the expansion element(s) displace(s) the expansion element(s) outwardly so the expansion element(s) can provide frictional contact with a borehole once inserted therein.   
     
     
         2 . An anchoring device as claimed in  claim 1  wherein the drill head and expansion element engage with each other via a first engagement portion on the drill head cooperatively fitting with a second engagement portion on the expansion element. 
     
     
         3 . An anchoring device as claimed in  claim 1  having two expansion elements located on opposite sides of the drill head to each other. 
     
     
         4 . An anchoring device as claimed in  claim 2 , wherein the first engagement portion is a protrusion configured to co-operatively engage with a second engagement portion in the form of a corresponding channel 
     
     
         5 . An anchoring device as claimed in  claim 2 , wherein the combination of first and second engagement portions forms a dovetail arrangement. 
     
     
         6 . An anchoring device as claimed in  claim 2 , wherein the first engagement portion is positioned on the inner surface of the expansion element(s) and the second engagement portion is positioned on the outer surface of the drilling assembly. 
     
     
         7 . An anchoring device as claimed in  claim 6 , wherein the second engagement portion is positioned at or about the leading edge of the drill head of the drilling assembly. 
     
     
         8 . An anchoring device as claimed in  claim 1 , wherein the second end of the elongate shaft includes a nut and a stop ring with a spring washer located therebetween. 
     
     
         9 . An anchoring device as claimed in  claim 1 , wherein the expansion element(s) includes ridges on their upper surface. 
     
     
         10 . An anchoring device as claimed in  claim 1 , wherein an inner surface of the expansion element(s) is tapered to cooperate with a tapered surface of the drill head. 
     
     
         11 . An anchoring device as claimed in  claim 10 , wherein the tapered surface of the expansion element(s) is a reverse taper with respect to the corresponding tapered surface of the drill head. 
     
     
         12 . An anchoring device as claimed in  claim 1 , wherein the expansion element(s) includes integrated barbs or skirts. 
     
     
         13 . An anchoring device as claimed in  claim 12 , wherein the integrated barbs or skirts are curved raised edges located at a distal end of the expansion element(s). 
     
     
         14 . An anchoring device as claimed in  claim 13 , wherein the integrated barbs or skirts are spring wires located at a distal end of the expansion element(s). 
     
     
         15 . An anchoring device as claimed in  claim 1 , wherein the elongate shaft is hollow to allow drilling fluid or other material to pass through the shaft. 
     
     
         16 . An anchoring device as claimed in  claim 15 , wherein the drill head includes apertures to allow drilling fluid or other material to pass from the elongate shaft through the drill head. 
     
     
         17 . An anchoring device including:
 a drilling assembly including an elongate shaft with first and second ends, a drill head at the first end, and the second end suitable for connection to a drilling apparatus; and   at least one expansion element;   wherein   the at least one expansion element includes a first engagement portion;   the drill head includes a second engagement portion;   the first and second engagement portions co-operate for retention of the expansion element(s) on the drilling assembly during a drilling operation;   the first and second engagement portions are configured to co-operate to:
 permit longitudinal movement of the expansion element(s) relative to a longitudinal axis of the drilling assembly; 
 substantially prevent radial movement of the expansion element(s) relative to the longitudinal axis of the drilling assembly; and 
 substantially prevent circumferential movement of the expansion element(s) relative to the drilling assembly; 
   the drill head and the expansion element respectively include co-operating contact surfaces for outward radial displacement of the expansion element(s) on relative longitudinal movement of the drill head.   
     
     
         18 . A component for an anchoring device including:
 a drill head; and   at least one expansion element;   characterised in that   the drill head and expansion element are configured to cooperatively interlock with each other and provide for directed movements of the drill head relative to a longitudinal axis of the shaft;   wherein   co-operating contact surfaces between the drill head and the expansion elements are configured such that movement of the drill head with respect to the expansion elements displaces the expansion element outwardly so the expansion element can provide frictional contact with a borehole once inserted therein.   
     
     
         19 . A component for an anchoring device including:
 a drill head; and   at least one expansion element;   wherein   the at least one expansion element comprises a first engagement portion;   the drill head includes a second engagement portion;
 the first and second engagement portions co-operate for retention of the expansion element(s) on the drill head during a drilling operation; 
 the first and second engagement portions are configured to co-operate to: 
   o permit longitudinal movement of the expansion element(s) relative to a longitudinal axis of the drill head;
   substantially prevent radial movement of the expansion element(s) relative to the longitudinal axis of the drill head; and   substantially prevent circumferential movement of the expansion element(s) relative to the drill head;   
   the drill head and the expansion element respectively include co-operating contact surfaces for outward radial displacement of the expansion element(s) on relative longitudinal movement of the drill head.   
     
     
         20 . A use of an interlock mechanism to connect at least one expansion element to a drill head;
 wherein   a first interlock portion is located on an internal surface of the expansion element and at least one second interlock portion is located on an outer surface of the drill head, wherein said first and second interlock portions are configured to:
 permit movement of the expansion element relative to the drill head along a longitudinal axis of the drill head; and 
 facilitate outward radial displacement of the expansion element. 
   
     
     
         21 . The use of an interlock mechanism as claimed in  claim 20 , wherein the first and second interlock portions substantially prevent radial movement of the expansion elements relative to the longitudinal axis of the drilling assembly. 
     
     
         22 . The use of an interlock mechanism as claimed in  claim 20 , wherein the first and second interlock portions substantially prevent circumferential movement of the expansion elements relative to the drilling assembly. 
     
     
         23 . A method of using the anchoring device as claimed in  claim 1  the method including the steps of:
 a) attaching the anchoring device to a drilling apparatus via a drive coupler; 
 b) positioning the drill head of the anchoring device against a surface; 
 c) rotating the anchoring device in a first direction of rotation via the drilling apparatus so that the rock bolt is drilled into the surface creating a borehole to a required depth; 
 d) rotating the shaft and drill head via the drilling apparatus in a second reverse direction of rotation to partially withdraw the shaft and drill head from the borehole thereby causing at least one expansion element located about the drill head to displace and provide frictional contact of the expansion element(s) within an internal surface of the borehole. 
 
     
     
         24 . A method of using an anchoring device of  claim 1 , including the steps of:
 a) attaching the anchoring device to a drilling apparatus via a drive coupler;   b) engaging the drive coupler with a nut positioned on an elongate shaft of the anchoring device;   c) if required, winding the nut in a first direction of rotation on the shaft until it abuts against a stop;   d) positioning a drill head of the anchoring device against a surface;   e) rotating the drill head in a first direction of rotation via the drilling rig so that the anchoring device is drilled into the surface such that the surface abuts a plate attached to the shaft;   f) rotating the nut on the shaft in a second reverse direction of rotation via the drilling apparatus until the nut abuts the plate;   g) further rotating the nut in the second reverse direction to partially withdraw the shaft and drill head from the borehole thereby causing at least one expansion element located about the drill head to displace and provide frictional contact of the expansion element(s) within an internal surface of the borehole.   
     
     
         25 . A method of using an anchoring device as claimed in either  claim 23 , wherein the first direction of rotation is a clockwise direction of rotation and the second direction of rotation is counter-clockwise. 
     
     
         26 . A method of connecting a drill head to at least one expansion element in an anchoring device as claimed in  claim 1 , characterised by the step of positioning the connecting portions which hold the expansion elements to the drill head so that they are shielded from the edges of the borehole during a drilling operation. 
     
     
         27 - 30 . (canceled)