摘要 |
A drill boom arrangement for positioning an elongated rock drilling apparatus to different drilling positions with respect to a support. The rock drilling apparatus is carried by a drill boom and the drill boom is mounted on a boom bracket. The boom bracket is slidable relative to the support in the latitudinal direction of the rock drilling apparatus. The boom bracket is moved along guiding means on the support means of a hydraulic cylinder. Means are provided for gearing up the piston stroke of the hydraulic cylinder. |