Abstract: The invention relates to transport vehicles and combinations thereof and their tow bar constructions comprising a tow bar journalled to the front of the chassis rotatably relative to a vertical and a horizontal axle, and structure for turning the axle. The structure for turning the axle comprise a steering lever secured to the tow bar rotatably relative to the center line of its vertical axle, and supporting arms secured at one end to the steering lever on opposite sides of the vertical axle and at the other end to the axle on its opposite sides.

Abstract: A method and an arrangement for controlling cable winding and unwinding in an electrically driven vehicle. In the method, cable winding and unwinding, respectively, are controlled on the basis of the position of driving and/or steering means of the vehicle. The arrangement comprises only one unwinding valve connected in series with a hydraulic motor, by which valve the counterpressure of the hydraulic fluid flowing through the hydraulic motor can be regulated during cable unwinding from the reel, and one unwinding valve respectively, by which the quantity of the hydraulic fluid coming to the hydraulic motor can be regulated during cable winding.

Abstract: The invention relates to an arrangement in connection with a hydraulically operated impact device, such as a breaking apparatus. The impact device includes a percussion piston, conduits for feeding pressure fluid into and out of the impact device, and a pressure accumulator. According to the inventive idea, the pressure accumulator is formed as an annular structure surrounding the percussion piston. It consists of sleeve-shaped pressure chambers that are separated by a sleeve-like diaphragm arranged between a frame and a sleeve. The pressure chambers are formed such that the inner circumference of the sleeve placed around the frame and the outer circumference of the frame are provided with recesses opposite one another.

Abstract: A rigid axle is turnably supported from a vehicle and carries wheels at its ends. The axle is supported from the frame of the vehicle at each of its ends by a support member which is pivotably connected to the axle and has suspension members at its opposite ends pivotably connected thereat. The suspension member at the forward end of the support member extends upwardly from the support member and is pivotably connected at its upper end to the frame. The suspension member at the opposite end of the support member extends downwardly and is connected at its lower end to an equalizer lever connected to the frame or to a suspension member connected to a support member of a following axle.

Abstract: The invention relates to a hydraulically operated impact device, such as a percussion hammer or some other breaking apparatus, comprising a control valve (6) for controlling pressure fluid supplied to and from the percussion piston (1) so that the direction of motion of the piston (1) can be changed in accordance with the cycle of operation of the impact device. According to the inventive idea, when the control valve (6) is in the impact position, the impact device is provided with a closed space that is partly bordered by the control valve and the percussion piston. The percussion piston (1) comprises a section which communicates with said space and which has a larger diameter than the upper end of the piston. The control valve and the percussion piston are thus able to move in the same direction until a connection is opened from this closed space to the upper end of the percussion piston (1).

Abstract: An arrangement for leading flexible elements, such as hoses, around a hose reel to a rock drill moving along a feed beam, in which the flexible elements are coupled immovably to the feed beam and to the rock drill, characterized in that the flexible elements are mounted on the hose reel in at least two successive layers in the radial direction of the hose reel and each radial layer is pivoted so as to revolve around a shaft of the hose reel independently of the other layers.

Abstract: An arrangement for controlling a winch cable connected to rock drilling equipment, the arrangement including the winch; a pressure fluid motor arranged to operate the winch; a pressure fluid pump for operating the pressure fluid motor; a pressure-controlled pressure relief valve installed between a pair of pressure fluid channels connected to the pressure fluid motor for setting a counterpressure of the pressure fluid motor when pulling the cable off a drum; and control means for controlling counterpressure of the pump; wherein the pump is a pressure-controlled volume flow pump and the control means comprise an adjusting device with which a control pressure prevailing in a control channel of the pressure relief valve can be adjusted for setting a limit pressure of the pressure relief valve and thus the counterpressure of the pressure fluid motor.

Abstract: In the arrangement, a feed beam made of an aluminum profile comprises a slide guide frame, whereby the outer surface of the slide guide frame and respectively, the inner surface of the slide guide are shaped and dimensioned in such a manner that when the slide guide is on the slide guide frame, they are tight against one another. The other edge of the slide guide flame and respectively, the corresponding edge of the slide guide are shaped in such a manner that when the slide guide is mounted in place, its edge is shape-locked relative to the slide guide frame. The slide guide is also secured by separate securing mechanism to the feed beam in such a manner that it cannot move either in the cross or longitudinal direction relative to the feed beam.

Abstract: A hydraulically operated percussion hammer comprising a percussion piston that reciprocates by means of the pressure of the pressure fluid, a main valve that is controlled by the position of the percussion piston and that guides the pressure fluid to the percussion piston in order to provide a reciprocating motion, and a pressure control valve that is placed in an outlet duct for pressure fluid and that prevents the flow of the pressure fluid from the percussion apparatus before the pressure of the pressure fluid in the inlet duct exceeds the set value of the pressure control valve. The percussion apparatus comprises a separate by-pass duct which allows the pressure fluid to flow from the pressure chamber of the percussion piston past the pressure control valve to the outlet duct until the percussion piston has reached a certain point during its return motion.

Abstract: A method for determining the position of a feed beam (3a to 3c) of a rock drilling equipment so that first, the position of a base (1) of the rock drilling equipment relative to rock is determined in the general system of coordination and after that, the position of the feed beam (3a to 3c) relative to the base (1) is measured. Measuring devices (6a to 6c) fixedly mounted in the base (1) at a distance from one another and at least two measuring devices (9a to 9c, 10a to 10c) attached to the feed beam at a distance from one another at a predetermined position are used in the method, whereby at least some of the measuring devices comprise a transmitter and at least some a receiver, respectively.

Abstract: An arrangement in a boom for a rock drilling unit, comprising a boom (1), pivotally connected to a frame (2) about a shaft (3), a lift cylinder (4) between the boom (1) and the frame (2), at the other end of the boom a feed beam pivotally connected about a shaft, parallel to the shaft (3), and a swing cylinder (10) between the feed beam and the boom. In the arrangement the lift cylinder (4) comprises three cylinder spaces, of which the first and second cylinder space (13a, 13b) may be connected to a hydraulic fluid supply for lifting or lowering the boom. The third cylinder space (13c) is inside a hollow piston rod (4b) and the cylinder comprises a fixed servo piston (4c) extending inside the piston rod. The third cylinder space (13c) is connected to the swing cylinder (10), to its first cylinder space (18a) and the second cylinder space (18b) of the swing cylinder (10) is connectable to a hydraulic fluid supply or receiver simultaneously with the first cylinder space (13a) of the lift cylinder.

Abstract: An arrangement for limiting the swing angle of a boom for a rock drilling unit when the boom is being lifted and lowered. In the arrangement, a control member is coupled to the boom, turning therewith. The control member includes a slot which receives a movable dowel pin. The dowel pin is coupled to control a relief valve so that when the boom is being lifted or lowered, and when it tends to turn outside a predetermined widest permissible swing angle, the control member controls the relief valve so that it lets hydraulic fluid into the swing cylinder for turning the boom in a reverse direction.

Abstract: An arrangement for mounting swing cylinders in a boom for a rock drilling unit which includes a frame, a boom pivotally connected about vertical and horizontal shafts, relative to the frame, a lift cylinder connected between the frame and the boom, and a swing cylinder connected between the frame and the boom. The unit also includes a support for a feed beam, pivotally connected to the other end of the boom about horizontal and vertical shafts, a tilt cylinder, connected between the support and the boom, and a transverse swing cylinder connected between the support and the boom. The swing cylinder is coupled at an angle (.alpha.), relative to the longitudinal axis of the boom, such that the longitudinal axis of the swing cylinder has a downward inclination from the frame toward the opposite end of the boom, so that with the boom in the middle of its upper and lower angles of altitude, the swing cylinder is essentially horizontal.

Abstract: An arrangement is provided for a telescope feeder of a rock-drilling machine, having two telescopic portions, between which is connected an extension cylinder so that the rock-drilling machine moves along one telescopic portion. The extension cylinder comprises a separate adjusting piston, which is mounted movably around the piston rod so that it can move irrespective of the piston of the extension cylinder. Three cylinder spaces are thus formed inside the extension cylinder and to each cylinder space is connected a separate channel for pressure medium, so that the adjusting piston can be displaced to a desired position.

Abstract: An arrangement for controlling the oscillation of a rock drilling equipment, comprising oscillation cylinders acting between a body and two crawlers, an oscillation selector valve allowing the oscillation cylinders to be interconnected. Locking valves are mounted in the oscillation cylinders, which valves prevent the flow of pressure fluid from the oscillation cylinders e.g., in the case of a hose damage, thus locking the crawlers and the body against movement relative to each other.

Abstract: A hydraulic actuator includes three cylinder spaces: a first cylinder space (6) located between a ring piston and a cylinder; a second cylinder space (7) between the ring piston and an auxiliary piston inside a hollow piston rod connected to the ring piston; and the third cylinder space (8) formed between the ring piston, the cylinder and the hollow piston rod.

Abstract: Arrangement in a hydraulically operated rock drilling equipment comprising a feed motor (3), a percussion device (2), and a hydraulic pump (1) for feeding hydraulic fluid to the feed motor (3) and the percussion device (2). The arrangement comprises a pressure control valve (17) connected to be controlled on the basis of the control signal of the feed regulation valve (8) when starting the drilling so that when the value of the control signal is below a predetermined switching value, the pressure relief valve (18) is connected to the percussion pressure line (13) of the percussion device (2), and when the control signal exceeds the switching value, the pressure control valve (17) disconnects the pressure relief valve (18) from the percussion pressure line (13) and connects the pressure difference valve (20) in communication with the percussion pressure line (13).

Abstract: The invention relates to a support arrangement for a divided articulated shaft in a vehicle comprising at least one driving axle (2) and at least one non-driving supporting axle (1), in which arrangement the articulated shaft (11) passes through the non-driving axle (1) and is supported near it to substantially follow the vertical movements of the non-driving axle (1), this axle being in turn supported from its middle to the frame (5) of the vehicle by means of an axle supporting unit (4). In order to avoid the lateral shifts and torsions of the articulated shaft (11), the shaft is supported onto said supporting unit (4) in the middle of the axle.