| 摘要 |
1,045,417. Rock drills. ATLAS COPCO A.B. June 16, 1965 [June 23, 1964], No. 25469/65. Heading B4C. An automatically controlled rock drill 20 is movable longitudinally by feed mechanism (not shown) relatively to a supporting shell 27 which is movable transversely by a compressedair motor 114 to predetermined locations for drilling a row of holes, the air supply to the motor 114 being controlled by a valve 124 which is opened only when the drill 20 is in its fully retracted position. The motor 114 rotates a threaded spindle 109 engaged by a travelling nut (not shown) secured to the shell 27, and compressed-air is supplied thereto from a feed conduit 122 via the valve 124, a conduit 127, a changeover valve 129, and a conduit 131. The drilling locations are determined by cams on a bar 135 which actuate the change-over valve 129 to halt the shell 27 at the desired positions by diverting compressed-air from the conduit 131 to a conduit 132 for actuating a plunger 134 to start the drill-feeding mechanism. Operation of the drill is commenced as it moves forwardly to permit opening of a valve 60 (not shown) controlling the compressed-air supply thereto, the valve 60 having been closed by an abutment on the shell 27 during the previous retraction of the drill. |
