Abstract: An annular wiper for piston rods, disposed in a cylindrical wall opening wherein an axially movable piston rod is running, comprises a reinforced ring of an elastic, somewhat flexible material having a portion with an inner diameter slightly greater than the outer diameter of the piston rod and an axially outwardly projecting and radially inwardly projecting lip with a somewhat smaller inner diameter than the outer diameter of the piston rod. The reinforcement comprises a first annular portion surrounding the periphery of the elastic ring, creating a torque center line for the resilient ring, and a second annular portion absorbing as a compressive force the radially inwardly directed force exerted by the elastic ring as it turns around the torque center line.

Abstract: The invention relates to a device for an articulated vehicle, for turning the vehicle about within a very limited space. According to the invention, the rear vehicle portion is provided with at least one supporting wheel mounted sideways, the axis of which lies in a vertical plane intersecting the vertical axis of articulation between the front and rear portions of the vehicle.

Abstract: The invention relates to a flexible, force-transmitting element, especially a resilient element for transmitting compression and tensile forces between two relatively movable components, especially between an axle and the end of a bogie pivot beam pivotally supported in a vehicle frame. The element comprises two end plates which are essentially parallel when the element is unloaded, a cylindrical, preferably solid, rubber body disposed between the end plates, and a mechanical connecting means which permits limited relative movement between the end plates. According to the invention, the connecting means comprises a link element disposed in the rubber body, said link element being movably mounted at both ends in a holder element fixed in the respective end plate.

Abstract: A method of controlling a power transmission device between a driving engine and a drive axle comprising a torque converter and an automatic step gearbox, and a power transmission device for carrying out the method. In the gearbox, an electric control device with a microcomputer permits the operator to select, by means of a direction selector, the desired driving direction of the vehicle even when moving opposite to the desired direction. When such a directional command signal is sent to the control device, the reversing gear control reverses the working direction of the gearbox to make it work in the opposite direction to the driving direction. This signal is also sent to the drive gear control in the control device which during retardation maintains the engaged gear in engagement. If the highest gear is engaged when the command signal is changed, however, downshifting to the next higher gear immediately takes place which gear is then maintained during retardation.

Abstract: A method of controlling a power transmission device between a driving engine and a drive axle comprising a torque converter and an automatic step gearbox, and a power transmission device for carrying out the method. In the gearbox, an electric control device with a microcomputer permits the operator to select, by means of a direction selector, the desired driving direction of the vehicle even when moving opposite to the desired direction. When such a directional command signal is sent to the control device, the reversing gear control reverses the working direction of the gearbox to make it work in the opposite direction to the driving direction. This signal is also sent to the drive gear control in the control device which during retardation maintains the engaged gear in engagement. If the highest gear is engaged when the command signal is changed, however, downshifting to the next higher gear immediately takes place which gear is then maintained during retardation.

Abstract: A vehicle such as a dumper with articulated steering has a load-carrying portion supported by two wheel-pairs mounted on bogies. One wheel-pair can be raised from the ground while the other, still on the ground, has softer suspension. In a vehicle with its two portions relatively swingable around a longitudinal axis, the two wheels on the ground are coupled so as to move relatively identically in relation to the vehicle frame. With one wheel-pair raised and the other suspended, the vehicle is still laterally stable. Spring suspension is obtained by tipping the bogies using a mechanism actuated by a hydraulic cylinder with a gas accumulator attached to the feeder line of the hydraulic cylinder. Gas spring suspension thus occurs only when one wheel-pair is raised.

Abstract: The invention relates to a bogie for vehicles of the type which has at least two movable axles against which the chassis of the vehicle rests over an equalizing beam arranged on either side of the chassis, the vertical forces being transmitted between the wheel axles and the equalizing beams by transmitting devices which are rigid when biased by tension and pressure stresses but yieldable to bending and shearing stresses. The connection points for these transmitting devices, at least at one axle, are located at a distance from the axle on a member which is rigidly connected to the axle, and a spring is arranged at such member to compensate for the moment conditioned by the distance between the axle and the connection points and resulting from movement of the axle.

Abstract: A dual hydraulic steering system for a vehicle has two steering circuits each having a pump and a steering valve unit. A first circuit is connected to the main working spaces of the double-acting steering cylinders while the second circuit is connected to the piston rod spaces of the cylinders. The first circuit has an engine driven pump while the second circuit has a ground wheel driven pump and an accumulator. Both circuits are connected to a common tank which is divided below a lowest normal oil level. Pressure switches and electromagnetic valves feed flow from the first circuit to the second in case of low pressure therein. This cross-over is prevented when a level switch detects low tank oil level.

Abstract: A method of felling and processing trees with a machine with a boom swingable about a vertical axis at the front end of the machine. The boom is extended in front of the machine and a tree is gripped and cut. The boom is swung while holding the tree vertical to a rearwards position, where the tree is lowered with the top to the rear. The root end is introduced into the rear-facing feed end of a processing unit on the machine. During processing, the tree is fed in the direction towards the front end of the machine.

Abstract: A device for cutting trees has two chain saws. For engaging the tree the chain saws are pivotable towards each other with the aid of feeding means. The power supplied to the saw chains is sensed and when an upper power limit is reached the feeding means is irreversibly set to the next lower of a small number of preselected feeding speeds.