| 摘要 |
An attachment (15) for a percussive rock drilling machine (12) for withdrawing a drill steel from a drilled hole. The drilling machine is of the kind which is displaceable along a feed beam (14) by a feeding motor. The attachment (15) comprises a spring housing (17) which contains a compressive spring (22) and a stopping member (23), the housing being suspended by flexible means (26, 27) from a yoke-shaped member (18) coupled on to the drilling machine body (19). The stopping member (23) is arranged to abut against a coupling sleeve (32) or the like on the drill steel (16). When retracting the drilling machine (12) by the feeding motorand starting the ordinary percussive action, the impacts directed downwards will be transformed to impacts directed upwards which loosen and withdraw the stuck drill steel (16) from the drilled hole. |
