GB946697A - Improvements in apparatus for drilling in earth covered rock - Google Patents

Abstract

946,697. Percussive drills. ATLAS COPCO A.B., and SANDVIKENS JERNVERKS A.B. March 28, 1961 [April 5, 1960], No. 11308/61. Heading B4C. [Also in Division E1] An adapter 47 has provision to be rotatably driven in the chuck 51 of a drill having a percussion and rotation motors 31, 32 and to support drill rods 77 and drill tubes 83 carrying bits 81, 86. The adapter has a flattened portion 50 which is slidable but non-rotatable in cavity 52 in the chuck which is rotated by a chain 66 driven by the pneumatic motor 32. The upper end of the adapter is struck by the hammer 37 of the pneumatic motor 31, a pipe 62 extending through the hammer into a bore 63 in the adapter to supply flushing liquid to the bit 81 through bores 93 in the drill rods. The drill is moved along guides 12 by a chain 25 driven by a pneumatic feed motor 22. The guides are carried by a frame 9 movable on wheels 10 on a frame 7 which is movable on wheels 8. An air hoist 106 adjacent a control panel 105 is provided for handling drill tubes. Drill rods and tubes are mounted on the adapter in the chuck, and the rotation and feed motors are started to drill through soft soil 3. When harder soil 4 or a boulder is reached the percussion motor is started, drilling proceeding by adding additional rods and tubes until the bits penetrate a few inches into hard rock 2. The tubes are disconnected from the adapter and drilling continues to drill a hole 116 using the bit 81 only. When the required depth of hole is reached the rods and bit 81 are withdrawn, a plastics tube is lowered into the tubes until its lower end seals with the top of the hole 116, and the tubes are -withdrawn.