Patent ID: 8256529

Claim:
Arrangement for employing a drill steel centralizer travelling on a feed beam of a rock drill machine, the arrangement comprising a feed cylinder for moving the drill machine in the drilling direction and back, at least one turning wheel mounted stationary in relation to the feed cylinder and a flexible feed member running around it and connected to both the drill machine and the feed beam, a drill steel centralizer mounted to travel on the feed beam and stationary in relation to the feed cylinder in the longitudinal direction of the feed beam and having a central opening for a drill rod, a transfer opening at the side of the central opening for transferring the drill rod to the central opening and away from it and means for closing the transfer opening during drilling, and a plurality of pressure fluid channels for feeding pressure fluid in to and out of a plurality of the pressure fluid chambers of the feed cylinder, wherein the centralizer has a pressure fluid-operated actuator for closing the transfer opening, and wherein one of the plurality of pressure fluid channels is connected from the pressure fluid chamber of the feed cylinder, to which pressure fluid is fed during drilling to move the drill machine in the drilling direction, to the actuator of the centralizer in such a manner that the pressure of the pressure fluid makes the actuator close the transfer opening.