| 摘要 |
1498305 Rotary and percussive rock drilling apparatus OY TAMPELLA AB 9 Jan 1976 [16 Jan 1975] 00812/76 Heading B4C [Also in Division B3] In an hydraulically-operated rotary and percussive rock-drilling apparatus, reciprocatory tool striking piston 2 is controlled by a sleevelike distribution slide valve movement of which itself is controlled hydraulically by movement of the piston due to intermittent communication between cylinder space 5, valve space G and exhaust channel 9 by means of piston recesses 4. The fluid escaping from the valve along channel 9 during movement of the valve in one direction (and the piston in the opposite direction) is used to drive the rotary hydraulic motor 10. Accumulators 11, 14 and 22 may be included to dampen out the pulses. |
