Patent GB-190705978-A (GB)
Title: Improvements in and relating to Rock-drills or Boring-tools
Inventor: HUTCHINGS JOHN
Filed: 1907-03-12
Granted: 1908-03-12
Abstract: 5978. Hutchings, J. March 12. Drilling. -In a powerdriven rotary rock drill, actuated directly or through gearing by a turbine driven by compressed air or other fluid, the connexion between the turbine and drill is made intermittently by alternatelyoperated clutches enclosed respectively in the turbine casing and in the cylinder around the drill rod. The tool and drill are formed with passages 2, 6 for water which is supplied through the drill 3, and the water, taking with it the borings, escapes into a flexible chamber e pressed into contact with the face of the rock by adjustable arms 9 attached to the drill case, or by air pressure from the apparatus. A pipe 13 leads from the chamber e to a settling-tank provided with filtering-media adapting the water for re-use. The drill holder c is keyed to and rotated by a turbine g, the rotors 26, 27, 28 of which are arranged in two sets for reversing the direction of rotation. The turbine g is movable on rails 87, with the aid of friction rollers 89, and the motive fluid is admitted alternately from valves 17, 18 connected by a rod 31. Air pressure is admited from a pipe 97 through a valve j and passages 40, 41, 42, 43 to the space 44 in front of a piston h connected by pins or teeth i to the rear side of the turbine g, and moves the piston back, causing cams 38 to grip shoes 39 on the drill holder c, and forcing the shoes into contact with the drill spindle 3 to rotate it. At the same time, air pressure is acting on the right-hand side of a piston 5 formed integrally with the drill holder c, the piston being in the position shown in dotted lines 45, thereby keeping the drill up to the work. When the piston 5 reaches the position shown in full lines, the valve j is automatically moved and closes communication with the space 44, and admits air through a passage 54 to the space 48 and thence through a passage 49 to the clutch chamber k, releasing the clutch 38. Simultaneously a similar clutch l, on a piston 4 in the position shown by dotted lines 51, forces shoes on a sleeve 53 into contact with the drill spindle 3 and moves it forward until the piston 4 is in the position shown in full lines; the valve j is then again moved and air is admitted through a passage 55 to the front of the piston 4, releasing the clutch l and carrying the clutch, piston 4, and sleeve 53 to their initial position. The piston 5 having meanwhile returned to its original position, the cycle of operations is repeated. Rotation of the clutch l is effected by prolonged teeth on the sleeve 53 and corresponding teeth on the interior of the drill holder c. The rod of the valve j is operated by cams on a rod connected to a sleeve 58 on the drill holder c and therefore moving therewith, a guide-rod 60 preventing rotation. To withdraw the drill from the hole, the valves 17, 18 are put in the position shown in Fig. 3, and the air passage 20 is closed by a valve 70, causing the turbine to cease rotating. At thesame time, air is admitted through a valve 74, which has been moved to close the passage 42, to the passage 43 and thence to the piston h, locking the clutch 38 on to the drill spindle 3. Air pressure on the left-hand faces of the pistons 4, 5 causes the drill to be drawn back to the extent of their stroke; the clutch 38 is then released and the motion of the piston h is reversed by air admitted through a valve 95 and the passage 49. The clutch h next takes a fresh grip, and the action is repeated until the drill is completely withdrawn. Lubrication is effected from a cup 80 from which oil flows to the bottom of the cylinder d. A disk is fixed to a sleeve and is formed with passages 84 through which oil is admitted to the cylinder 48 by ball valves when suction is created by the withdrawal of the sleeve 53 from its casing 85. The drill 3 may be lengthened as required by the introduction of intermediate sections.