A device for reciprocating motion of a rotating drilling body of a drilling machine in the longitudinal direction of a hole drilled in rock or ground includes two cylinder-piston devices which via chains are connected to a carriage carrying the drilling body and which comprise parallel piston rods, the ends of which are supported by a frame on the machine, and cylinders movable along the piston rods and connected to each other and via the chains also to the carriage. To increase the feeding velocity of the carriage or to increase the force of the carriage one of the cylinders or both cylinders, respectively, are selectively fluid pressurized.
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