Abstract: An arrangement intended to be part of a rock drilling machine for percussive drilling. The arrangement includes a casing part with at least one plane end plane. The end plane includes at least a first region and a second region. The first region includes at least a part of the outer contour of the end plane and includes of a material that resists corrosion.

Abstract: A percussion device (5) for a rock drilling machine (1) including a percussive piston (6; 15) which is reciprocally movable inside a cylinder and an impact receiving element (7;16) with an impact surface (A;A?), against which the percussive piston is arranged to perform strikes in an impact direction for transferring of percussive energy through Shockwaves to a percussive tool. The percussion device is distinguished by the impact receiving element (7; 16) including a Shockwave modifying portion (9; 17) which extends in a direction opposite to the impact direction as seen from a plane (P; P?) through the impact surface (A; A?). The invention also concerns a rock drilling machine and a rock drilling rig.

Abstract: A percussion device has a machine housing (1), a forwards and backwards movable percussion piston (2) in the machine housing, and a reciprocatingly movable valve body (6) in the machine housing. The percussion piston has a first (4) and a second (5) driving surface subjected to pressure to drive the percussion piston (2) forwards and backwards. The valve body (6) has a first end surface (12) and a second end surface (13) for driving the valve body in first and second directions by applied pressure. The valve body (6) is arranged over a channel (7) in the machine housing, to connect at least the second (5) driving surface alternately to a pressure source (8) or to low pressure (9), and the second end surface (13) is alternately connectable by the percussion piston (2) to the pressure source (8) or, over a valve device (11) for creating a counter-pressure, to the low pressure (8).

Abstract: A rock drilling machine with a first control means (21, 22) within a second piston (6) and acting on a first piston (13) such that it counteracts displacement of the relative positions of a first and a second control device at the moment of contact of the second piston onto the drill rod or onto a part (9) connected to this. Furthermore, a rock drill rig comprising such a rock drilling machine and a method for counteracting the said displacement. Significant improvements in reproducibility for impact mechanism stability over long manufacturing series are achieved through the invention. In the same way, the lifetime of rock drilling devices manufactured according to the invention is extended through the impact mechanism acting in a more stable manner despite wear of component parts. It is furthermore possible to dimension for higher rates of impact without risking the impact mechanism stability.

Abstract: An arrangement intended to be part of a rock drilling machine for percussive drilling. The arrangement includes a casing part with at least one plane end plane. The end plane includes at least a first region and a second region. The first region includes at least a part of the outer contour of the end plane and includes of a material that resists corrosion.

Abstract: A method for controlling a fluid operated percussive device, which inside an axially extending cylinder room (3) of a housing (2) of the percussive device includes a to and fro moveable percussive piston (1), which is adapted for performing strikes in a striking direction (A) and which includes a signal portion (4) for controlling a main valve (5), which is adapted to intermittently transmit pressure fluid to at least one driving chamber (7) for the percussive piston. An auxiliary valve (9) is controlled for transmitting fluid contact between at least one auxiliary channel means (13,14) with a channel opening in the cylinder room (3), and the main valve (5) over the signal portion (4), for switching the main valve (5) before the percussive piston, in operation, has reached at least one of said regions. The invention also concerns a percussive device and a rock drilling machine.

Abstract: A valve device (V, 4?) for controlling the movement in a machine housing (2) of a reciprocating percussion piston (3) of a percussion device (1) for a rock drilling machine with a first chamber (5) that can be pressurized for forward driving of the percussion piston (3) and a second chamber (8) that can be pressurized for back-driving of the percussion piston (3), wherein the valve device includes a to and fro movable valve element (20), the movement of which being controlled as a response to the position of a valve portion (V) of the percussion piston in a valve housing portion by periodically pressurizing a signal chamber (21) actuating the movement of the valve element over signal conduit means (22, 23, 24).

Abstract: A rock drilling machine with a first control means (21, 22) within a second piston (6) and acting on a first piston (13) such that it counteracts displacement of the relative positions of a first and a second control device at the moment of contact of the second piston onto the drill rod or onto a part (9) connected to this. Furthermore, a rock drill rig comprising such a rock drilling machine and a method for counteracting the said displacement. Significant improvements in reproducibility for impact mechanism stability over long manufacturing series are achieved through the invention. In the same way, the lifetime of rock drilling devices manufactured according to the invention is extended through the impact mechanism acting in a more stable manner despite wear of component parts. It is furthermore possible to dimension for higher rates of impact without risking the impact mechanism stability.

Abstract: A method for controlling a fluid operated percussive device, which inside an axially extending cylinder room (3) of a housing (2) of the percussive device includes a to and fro moveable percussive piston (1), which is adapted for performing strikes in a striking direction (A) and which includes a signal portion (4) for controlling a main valve (5), which is adapted to intermittently transmit pressure fluid to at least one driving chamber (7) for the percussive piston. An auxiliary valve (9) is controlled for transmitting fluid contact between at least one auxiliary channel means (13,14) with a channel opening in the cylinder room (3), and the main valve (5) over the signal portion (4), for switching the main valve (5) before the percussive piston, in operation, has reached at least one of said regions. The invention also concerns a percussive device and a rock drilling machine.

Abstract: A percussion device (5) for a rock drilling machine (1) including a percussive piston (6; 15) which is reciprocally movable inside a cylinder and an impact receiving element (7;16) with an impact surface (A;A?), against which the percussive piston is arranged to perform strikes in an impact direction for transferring of percussive energy through Shockwaves to a percussive tool. The percussion device is distinguished by the impact receiving element (7; 16) including a Shockwave modifying portion (9; 17) which extends in a direction opposite to the impact direction as seen from a plane (P; P?) through the impact surface (A; A?). The invention also concerns a rock drilling machine and a rock drilling rig.

Abstract: A rock drilling machine includes a sleeve having openings surrounding a portion of a lubrication channel. A groove surrounds the sleeve, and one end of a second channel is connected to the groove. The other end of the second channel is connected to a lubrication point so that lubricant from the lubrication channel is distributed from the lubrication channel, through the sleeve and groove to the second channel, and from the second channel to a lubrication point of the rock drilling machine.

Abstract: A mixing device for mixing air and water in a water purifier includes a water inlet pipe (2) and an air inlet pipe (3). The air inlet pipe (3) extends coaxially within the water inlet pipe (2) and defines therewith an annular gap (4) for providing an annular water jet. Downstream of the annular gap (4) there is provided a mixing member (6) for mixing water and air. The mixing member (6) includes a water flow disturbing device (7) which is provided to be hit by the annular water jet. At least those parts (2a) of the water inlet pipe (2) and/or those parts (3a) of the air inlet pipe (3) which define the annular gap (4), are made of plastic material. The water flow disturbing device (7) includes at least one helical member (8) which extends along the inner side of the mixing member (6) around through-flow portions (6a) thereof within the helical member (8) such that helical movements are imparted to the annular jet of water when it flows downwards through the through-flow portions (6a).

Abstract: A valve device (V, 4?) for controlling the movement in a machine housing (2) of a reciprocating percussion piston (3) of a percussion device (1) for a rock drilling machine with a first chamber (5) that can be pressurized for forward driving of the percussion piston (3) and a second chamber (8) that can be pressurized for back-driving of the percussion piston (3), wherein the valve device includes a to and fro movable valve element (20), the movement of which being controlled as a response to the position of a valve portion (V) of the percussion piston in a valve housing portion by periodically pressurising a signal chamber (21) actuating the movement of the valve element over signal conduit means (22, 23, 24).

Abstract: A percussion device (1) with a reciprocating percussion piston (3), includes a first chamber (5) that can be pressurized for forward driving of the percussion piston (3) and a second chamber (8) that can be periodically pressurized for back-driving of the percussion piston (3). The percussion device includes at least one driving piston (7) arranged for actuating the back-driving of the percussion piston (3) wherein a portion of said driving piston (7) is arranged to enter into the second chamber (8) for pressure actuating on a driving surface of the driving piston by pressure medium being present in this chamber in the direction of back-driving, wherein the driving piston (7) includes means for back-driving co-operation with the percussion piston (3), and wherein the driving piston (7) is free for axial movement with respect to the percussion piston (3), opposite the direction of back-driving. The invention also concerns a method and a rock drilling machine.

Abstract: A percussion device (1) with a reciprocating percussion piston (3), includes a first chamber (5) that can be pressurized for forward driving of the percussion piston (3) and a second chamber (8) that can be periodically pressurized for back-driving of the percussion piston (3). The percussion device includes at least one driving piston (7) arranged for actuating the back-driving of the percussion piston (3) wherein a portion of said driving piston (7) is arranged to enter into the second chamber (8) for pressure actuating on a driving surface of the driving piston by pressure medium being present in this chamber in the direction of back-driving, wherein the driving piston (7) includes means for back-driving co-operation with the percussion piston (3), and wherein the driving piston (7) is free for axial movement with respect to the percussion piston (3), opposite the direction of back-driving. The invention also concerns a method and a rock drilling machine.

Abstract: Percussion device including a machine housing (1), a forwards and backwards movable percussion piston (2) in the machine housing, and a reciprocatingly movable tubular valve body (6) inside the machine housing, said percussion piston (2) being arranged to subject a tool (3) to impact, and said percussion piston including a first (4) and a second (5) driving surface arranged to be pressurized in order to drive the percussion piston forwards and backwards, said valve body (6) including a first end surface (12) and a second end surface (13), wherein pressurizing the first end surface (12) tends to drive the valve body in a first direction and pressurizing the second end surface (13) tends to drive the valve body in a second direction, whereby the valve body (6) is arranged, over a channel (7) arranged in the machine housing, to connect at least the second (5) of the driving surfaces alternately to a pressure source (8) or to low pressure (9), wherein an inner room (31) in the tubular valve body (6) is continuous

Abstract: A method of cutting a strip of sheet metal, including feeding out a continuous strip of sheet metal in a feeding direction, cutting the strip into a plurality of lengths, including making a wave shaped cut between each length and an adjacent length, wherein each of a forward edge and a following edge of each length include a plurality of waves, and selecting at least one of a radius of each of the plurality of waves and a spacing between adjacent ones of the plurality of waves based on a cutting angle, wherein the cutting angle is oblique with respect to the feeding direction.

Abstract: Impact adapter for transfer of impacts and rotation from an impact rock drilling machine to a drill string comprising a first end (5) for connection to a drill string and a second end provided with ridges (7) and interposed grooves (8) for transfer of rotation. The grooves (8) at the end (9) directed away from the first end (5) of the impact adapter (2) are widened in the direction away from the first end (5).

Abstract: Rock drilling device including a rock drilling machine (1) which is movable forwards and backwards along a feed beam, (2 wherein the rock drilling machine (1) is pivotal around an axis (3) which is arranged along the rock drilling machine (1), and a channel (4) for supply of lubricant to points of lubrication in the rock drilling machine (1), wherein the channel (4) includes a sleeve (5) which is provided with a number of generally radial holes (6) that are distributed along the circumference of the sleeve (5), that a groove (7) is arranged around the sleeve (5) in connection with the radial holes (6), and that the radial holes (6) are dimensioned such that a part of the lubricant leaves the channel (4) through the radial holes (6).

Abstract: Percussion device including a machine housing (1),? a forwards and backwards movable percussion piston (2) in the machine housing, and a reciprocatingly movable valve body (6) in the machine housing, said percussion piston (2) being arranged to, subject a tool (3)? to impacts, and said percussion piston including a first (4) and a second (5) driving surface intended to be subjected to pressure in order to drive the percussion piston (2), forwards and backwards, said valve body ** (6) including a first end surface (12) and a second end surface (13), wherein the pressurizing of the first end surface (12) tends to drive the valve body in a first direction and pressurizing of the second end surface (13), tends to drive the valve body in a second direction, whereby the valve body (6) is arranged, over a channel (7) arranged in the machine housing, to connect at least the second (5) of the driving surfaces alternately to a pressure source (8) or to low pressure (9), wherein the second end surface (13), by the percu