GB191221305A - Improvements in Rock Boring Apparatus and Carriages therefor. - Google Patents

Abstract

21,305. May Mining Co., and Stocks, C. H. Sept. 19. Drills.-In a portable hydraulic rock-boring apparatus, the boring-engine is pivotally carried at the free end of a balanced twin boom or jib which is supported by a universal capstan on a carriage. The carriage 1 is locked in position by means of two sliding bars 3, 4, adapted to engage the walls, or the roof and floor, of a tunnel, the bar 3 having a rack 5 and the bar 4 carrying a bracket 6 supporting a spindle 7 fitted with a pinion 8 engaging the rack. The bars 3, 4 are first moved by rotating the shaft 7 by a hand-wheel 11; a clutch 10 is then put in gear, and the movement is completed by worm gearing 9, 12. The carriage carries a pillar 16 about which a capstan head 18, provided with a lignum-vitµ facing 21, may be rotated. This capstan head carries a second capstan head 22 which may be rotated by skew and worm gearing from a shaft 29. Within the capstan head 22 is a shell 31 which may be rotated by worm gearing from a shaft 34 and which carries the balanced twin boom or jib 23. At the end of the boom, the boring-engine is pivotally mounted and is adjusted through pitmans 40 from a right and left handed screw 37. A Pelton wheel or water turbine 42 acts through worm gearing to rotate the boring-bar 43 which is fed forward or backward by a ram in a cylinder 46. Valves 47, 48 control the water supply. The feed-pressure may be reduced by allowing some of the water to pass through a by-pass in the ram, such water being exhausted through a valve 47<a> at a predetermined pressure. The carriage wheels are held on their axles by nuts 49 which may be locked by plates 50.