| 摘要 |
1300109 Rock drills TORQUE TENSION Ltd 15 July 1971 [23 Oct 1970] 50572/70 Heading B3C A control device 4 for a rock drill 7 comprises an inlet 17 for connection to a fluid pressure supply pipe 10, the inlet leading to a first outlet 18 connected to a pipe 8 via a motoroperating valve 24, and to second and third outlets 22, 23, connected to pipes 2 and 3 respectively by way of a drill leg-actuating valve 57, and by way of a manually settable rotary selector 64, which allows fluid to leave through the second outlet but not the third, or can be set to allow the fluid to leave through the third outlet but not the second, the motoroperating and leg-actuating valves 24, 57, being normally closed, and there being independently manually operable lever means 58, 30, for opening one or the other of the valves. Pipes 2 and 3 connect device 4 with the extensible leg 1 of the rock drill, and motor 5 is connected to device 4 by pipes 8, 9, which screw into outlet 18 and inlet 19 on the device. During operation leg 1 is extended to feed the drill. Other valves 33, 43 and 76 are provided in device 4. Fluid is discharged to a tank from an outlet 73. |
