The present invention relates to a drilling device. The device comprises at least one drill rod, the or each drill rod having a first cylindrical wall defining an elongate chamber for receiving a working fluid to form a fluid column, the length of the fluid column being equal to a total length of the elongate chambers of the or each drill rod. The device also comprises a displacement excitation device arranged at a proximal end of the fluid column and configured to excite the fluid column to cause the working fluid in the fluid column to oscillate, wherein the excitation device is configured to excite the fluid column at an excitation frequency at or within 10% of a natural frequency of the fluid column determined based on the fluid column having a fixed boundary condition at a proximal end thereof. The device further comprises a tool piston moveably mounted at a distal end of the fluid column and a drilling tool connected to the tool piston such that the oscillation of the working fluid in the fluid column imparts an oscillating force to the drilling tool.

A down the hole rock drilling machine and a method of drilling rock. The drilling machine includes a reciprocating piston, which has a sleeve-like configuration. Inside a central opening of the piston is arranged one or more fluid passages for conveying pressurized fluid during the work cycle of an impact device of the drill machine.

A pressurized fluid flow system for percussive mechanisms comprises a cylinder coaxially disposed in between an outer casing and a piston which reciprocates due to the changes in pressure of the pressurized fluid contained inside a front chamber and rear chamber located at opposites sides of the piston. The discharge of fluid from these chambers being conducted through a set of discharge channels and the supply of fluid to the front chamber being conducted through a set of supply channels and a front set of recesses. The supply of fluid to the rear chamber being conducted through a piloted valve.

A pressurized fluid flow system for percussive mechanisms comprises a cylinder coaxially disposed in between an outer casing and a piston which reciprocates due to the changes in pressure of the pressurized fluid contained inside a front chamber and rear chamber located at opposites sides of the piston. The discharge of fluid from these chambers being conducted through a set of discharge channels and the supply of fluid to the front chamber being conducted through a set of supply channels and a front set of recesses. The supply of fluid to the rear chamber being conducted through a piloted valve.

A flushing element, rock drilling machine and method of providing a flushing space around a shank adapter of a rock drilling machine. The flushing element surrounds the shank adapter passing through it. The flushing element has a feed opening for feeding flushing agent to the flushing space and at least two sealing housings for flushing sealings and wherein the flushing sealings are on opposite axial sides of the flushing space. Furthermore, the flushing element has split configuration whereby it is mountable and demountable in radial direction.

A shank adapter, rock drilling machine and method of mounting a shank adapter of a rock drilling machine inside a slide bearing element. The shank adapter includes a coupling head and a rotation portion at its opposite ends, and a flushing portion located therebetween. Outer diameters of the coupling head and the rotation portion are both greater than outer diameters of portions of the shank adaptor located therebetween.

Damping device for a percussion device of a hydraulic rock drilling machine (1) with a striking direction (R), including a damping piston (5) for action in an axial direction against a tool, wherein the damping piston (5) exhibits a first piston portion (6), which is received in a first damping chamber (7) and a second piston portion (8), which is received in a second damping chamber (9). In operation, in a normal striking position of said percussion device, the damping piston (5) is set against a fixed stop (19) against movements in the striking direction. A damping slot (10) is established between the first (7) and the second (9) damping chamber in all axial positions of the damping pistons, and the first damping chamber (7) is pressurized with a hydraulic pressure. The invention also concerns a percussion device and a rock drilling machine.

A flushing element, rock drilling machine and method of providing a flushing space around a shank adapter of a rock drilling machine. The flushing element surrounds the shank adapter passing through it. The flushing element has a feed opening for feeding flushing agent to the flushing space and at least two sealing housings for flushing sealings and wherein the flushing sealings are on opposite axial sides of the flushing space. Furthermore, the flushing element has split configuration whereby it is mountable and demountable in radial direction.

A shank adapter, rock drilling machine and method of mounting a shank adapter of a rock drilling machine inside a slide bearing element. The shank adapter includes a coupling head and a rotation portion at its opposite ends, and a flushing portion located therebetween. Outer diameters of the coupling head and the rotation portion are both greater than outer diameters of portions of the shank adaptor located therebetween.

The invention relates to a device for generating oscillations for a construction machine, comprising a housing, a piston which is movable back and forth in a working chamber in the housing between a first return point and a second return point, a pressurized fluid supply through which in each case pressurized fluid can be fed into and discharged from the working chamber via at least one actuatable control valve in the region of the first return point and the second return point, wherein the piston can be induced into a reciprocating motion in order to generate the oscillations, and a control unit which is configured to actuate the at least one control valve and by means of which the movement of the piston in the working chamber is controllable and variable. According to the invention, it is provided that the control unit is configured to control the piston in a first operating mode for generating oscillations and in a second operating mode for generating impact pulses, wherein a strike surface is formed on at least one end side of the working chamber, onto which surface the piston strikes when it reaches at least one return point in order to generate an impact pulse.