Abstract: A piston guiding element, rock drilling machine and method for supporting a front end portion of a percussion piston of a rock drilling machine. The piston guiding element includes a braking recess at its rear end. The element further includes at least one bearing sleeve, which is provided with two axially successive slide bearing sections. Hydraulic fluid is conveyed between the slide bearing sections via a feed system.

Abstract: A control valve, an impact device for a rock breaking apparatus, and a method are provided. The control valve is an elongated piece with a central axis and radial outer and inner surfaces (Ros, Ris). The control valve includes several control surfaces disposed at axial distances from each other for controlling hydraulic fluid flows (Hff) in response to axial control movement (M). One or more radial surfaces of the control valve include one or more slanted surface (SS) a longitudinal direction of which have oblique orientation in relation to the central axis (Ca) of the control valve. The control valve rotates or turns during a working cycle due to hydraulic flow effecting on the slanted surfaces.

Abstract: A rock drilling arrangement includes an impact device having a frame, pressure chambers in the frame, and a piston arranged in the impact device. The arrangement further includes a rear mounting arrangement for attaching the impact device to a carriage, a front mounting arrangement for attaching the impact device to a machine component, at least one fore pressure accumulator arranged on a front side of the rear mounting arrangement in an axial direction of the piston, and at least one rear pressure accumulator arranged on a back side of the rear mounting arrangement. The fore pressure accumulator and the rear pressure accumulator are connected to one of the pressure chambers and arranged to absorb pressure fluctuations in the pressure chambers.

Abstract: A piston guiding element, rock drilling machine and method for supporting a front end portion of a percussion piston of a rock drilling machine. The piston guiding element includes a braking recess at its rear end. The element further includes at least one bearing sleeve, which is provided with two axially successive slide bearing sections. Hydraulic fluid is conveyed between the slide bearing sections via a feed system.

Abstract: A rock drilling arrangement includes an impact device having a frame, pressure chambers in the frame, and a piston arranged in the impact device. The arrangement further includes a rear mounting arrangement for attaching the impact device to a carriage, a front mounting arrangement for attaching the impact device to a machine component, at least one fore pressure accumulator arranged on a front side of the rear mounting arrangement in an axial direction of the piston, and at least one rear pressure accumulator arranged on a back side of the rear mounting arrangement. The fore pressure accumulator and the rear pressure accumulator are connected to one of the pressure chambers and arranged to absorb pressure fluctuations in the pressure chambers.

Abstract: A component for a rock breaking system is magnetized into a state of remanent magnetization. The remanent magnetization of the component has a predetermined varying magnetization profile relative to geometry of the component, the varying magnetization profile describing varying magnetization intensity in the component relative to the geometry of the component.

Abstract: A control valve for controlling flow of a pressure fluid in a breaking device includes a sleeve-like control valve having at least one opening enabling flow of the pressure fluid through the opening. The at least one opening includes at least one wall, at least a part of which is not arranged in a direction parallel to a radial direction of the control valve extending through the middle point of the cross section of the opening on the outer circumference of the control valve, such that the pressure fluid flowing through the opening may be arranged to rotate the control valve about the longitudinal axis of the control valve.

Abstract: A breaking device includes a frame, an impact device having a pressure chamber with a rear pressure chamber and a front pressure chamber. The breaking device further includes a first low pressure port at the rear pressure chamber, a first low pressure channel and a first low pressure accumulator connected to the first low pressure channel. The breaking device further includes a second low pressure port at the rear pressure chamber substantially opposite to the first low pressure port, second low pressure channel and a second low pressure accumulator connected to the second low pressure channel. The first low pressure accumulator and the second low pressure accumulator are arranged at the outer circumference of the frame of the breaking device at different positions in the axial direction of the breaking device.

Abstract: A component for a rock breaking system is magnetized into a state of remanent magnetization. The remanent magnetization of the component has a predetermined varying magnetization profile relative to geometry of the component, the varying magnetization profile describing varying magnetization intensity in the component relative to the geometry of the component.

Abstract: A percussion piston for a rock drill machine having a pilot cylinder, a distributor and a pressure medium includes a control edge configurable to cause a change in the position of the distributor in a direction parallel to the axial direction of the percussion piston as the percussion piston moves in the impact direction (A) in relation to the pilot cylinder. The control edge of the percussion piston includes at least one notch provided on the outer periphery of the control edge and arranged to cause a start of a state change for the distributor before the control edge of the percussion piston passes by a corresponding control edge provided on the distributor or pilot cylinder.

Abstract: A percussion piston for a rock drill machine having a pilot cylinder, a distributor and a pressure medium includes a control edge configurable to cause a change in the position of the distributor in a direction parallel to the axial direction of the percussion piston as the percussion piston moves in the impact direction (A) in relation to the pilot cylinder.

Abstract: A breaking device includes a frame, an impact device having a pressure chamber with a rear pressure chamber and a front pressure chamber. The breaking device further includes a first low pressure port at the rear pressure chamber, a first low pressure channel and a first low pressure accumulator connected to the first low pressure channel. The breaking device further includes a second low pressure port at the rear pressure chamber substantially opposite to the first low pressure port, second low pressure channel and a second low pressure accumulator connected to the second low pressure channel. The first low pressure accumulator and the second low pressure accumulator are arranged at the outer circumference of the frame of the breaking device at different positions in the axial direction of the breaking device.

Abstract: A control valve for controlling flow of a pressure fluid in a breaking device includes a sleeve-like control valve having at least one opening enabling flow of the pressure fluid through the opening. The at least one opening includes at least one wall, at least a part of which is not arranged in a direction parallel to a radial direction of the control valve extending through the middle point of the cross section of the opening on the outer circumference of the control valve, such that the pressure fluid flowing through the opening may be arranged to rotate the control valve about the longitudinal axis of the control valve.

Abstract: The invention relates to a percussion device having a body and a percussion piston moving therein, pressure fluid spaces in the rear and front ends of the percussion piston and pressure fluid channels for feeding pressure fluid into the percussion device. The percussion piston and the control valve comprise surfaces, which, when aligned, substantially close the pressure fluid flow from the pressure fluid space locating behind the percussion piston in front of the control valve, whereby the produced pressure displaces the control valve to another position.

Abstract: The invention relates to a percussion device having a body and a percussion piston moving therein, pressure fluid spaces in the rear and front ends of the percussion piston and pressure fluid channels for feeding pressure fluid into the percussion device. The percussion piston and the control valve comprise surfaces, which, when aligned, substantially close the pressure fluid flow from the pressure fluid space locating behind the percussion piston in front of the control valve, whereby the produced pressure displaces the control valve to another position.

Abstract: The invention relates to a percussion device comprising two percussion pistons alternately making a percussion motion and a control valve for controlling the percussion pistons. The control valve (7) comprises a slide (8) affected by a force so that the slide is generally in a first position, but moves at the end of the percussion motion of the first percussion piston from the first position to a second position and correspondingly back to the first position at the end of the percussion motion of the second percussion piston (4).

Abstract: The invention relates to a control valve, a percussion device and a method of controlling a working cycle of a percussion device. A percussion device (1) for breaking rock includes an impact element (8) controlled by a control valve (2). The control valve includes a control element (5) arranged to control channels (7b) leading to a working pressure surface (9) of the impact element (8). The control element, during a working cycle of the control valve, is arranged to open and close pressure channels at several connecting moments so that during one working cycle of the valve, several impact pulses are arranged to be produced.

Abstract: The invention relates to a control valve, a percussion device and a method of controlling a working cycle of a percussion device. The percussion device (1) used for breaking rock comprises an impact element (8), which is controlled by a control valve (2). The control valve comprises a control element (5), which is arranged to control channels (7b) leading to a working pressure surface (9) of the impact element (8). The movement of the control element to its extreme position is arranged to form a closed pressure space, where pressure medium compresses and converts kinetic energy of the control element into pressure energy. The pressure energy is re-converted into kinetic energy and utilized when the control element changes its direction.

Abstract: The invention relates to a control valve, a percussion device and a method of controlling a working cycle of a percussion device. The percussion device (1) used for breaking rock comprises an impact element (8), which is controlled by a control valve (2). The control valve comprises a control element (5), which is arranged to control channels (7b) leading to a working pressure surface (9) of the impact element (8). The movement of the control element to its extreme position is arranged to form a closed pressure space, where pressure medium compresses and converts kinetic energy of the control element into pressure energy. The pressure energy is re-converted into kinetic energy and utilized when the control element changes its direction.

Abstract: The invention relates to a control valve, a percussion device and a method of controlling a working cycle of a percussion device. A percussion device (1) for breaking rock includes an impact element (8) controlled by a control valve (2). The control valve includes a control element (5) arranged to control channels (7b) leading to a working pressure surface (9) of the impact element (8). The control element, during a working cycle of the control valve, is arranged to open and close pressure channels at several connecting moments so that during one working cycle of the valve, several impact pulses are arranged to be produced.