Patent attributes
A rock drilling machine includes a frame, and arranged inside the frame is a drill rod. A hammer gear is arranged to hammer the drill rod rear end. There is arranged around the drill rod a position sleeve and an arrangement to move position sleeve in an axial direction against hammering piston so that a counter surface of the position sleeve meets the counter surface whereby, on continuing the positioning, the drill rod is movable to the point desired. The counter surface by use of a spring element is arranged to flex in regard to the other structure of the position sleeve so that in the drilling position the sleeve is arranged to be freely backing against the front side of the drilling machine, and when in the drilling operation the positioning impact on the position sleeve against the hammering piston is removed.
