Patent ID: 8733467
Filing Date: 2014-05-27
Classification: B25D,E21B

Abstract:
1. A rock drilling machine that comprises: a body; a percussion device that comprises a percussion element for generating stress pulses; a drill shank that is an elongated piece arranged in front of the percussion element in a stroke direction, the drill shank having an impact surface for receiving said stress pulses and, further, the drill shank being movable in an axial direction relative to the body; and an axial bearing that comprises at least one pressure medium-operated axial piston by means of which the drill shank is pushed in the axial direction relative to the body a predefined travelling length toward the stroke direction, whereby the impact surface of the drill shank is settable at a required axial point for receiving stress pulses, wherein the axial piston comprises at least one working pressure surface located in at least one working pressure space belonging to the axial bearing, to which pressure of the pressure medium is fed from at least one feed channel, whereby a force in the stroke direction is directable to the axial piston, wherein the axial bearing comprises at least one axial bearing module that comprises the at least one axial piston, at least one seal, at least one bearing surface, and a module frame, wherein an outer surface of the module frame is furnished with at least one fixed support member for transmitting supporting forces caused by operation of the axial bearing directly from the axial bearing to the body of the rock drilling machine, and wherein the body of the rock drilling machine is at least at the axial bearing a uniform piece without joint surfaces.