Abstract: The present invention relates to a device for generating vibrations for a ground compaction machine, in particular a self-propelled ground compaction roller, comprising a first imbalance mass and a second imbalance mass, each of which is rotatably mounted, a first hydraulic motor configured to set the first imbalance mass into rotation, a planetary gear connected to the first hydraulic motor and via which the second imbalance mass can be driven, a second hydraulic motor which is also connected to the planetary gear and is configured to change the transmission ratio from the first hydraulic motor to the second imbalance mass via the planetary gear, wherein a third hydraulic motor is provided which is also connected to the planetary gear and is also configured to change the transmission ratio from the first hydraulic motor to the second imbalance mass via the planetary gear.

Abstract: A steering device for a steerable machine, particularly a construction machine, comprising a steering element for manual input of steering commands, a steering actuator for driving a steering adjustment of a travel unit of the construction machine, and a transmission device, which is arranged between the steering element and the steering actuator, the transmission device including an actuator orbitrol for driving the steering actuator. Furthermore, the invention relates to a construction machine having such a steering device, as well as to a method for steering a steerable machine, particularly a construction machine.

Abstract: The present invention relates to a method for operating a hydraulic system of a self-propelled road paver, in particular, for the supply of hydraulic oil as needed to a closed hydraulic circuit of the road paver, a hydraulic system of a road paver for performing the method and a road paver having such a hydraulic system. The extraction and/or return of the quantity of hydraulic oil occur depending on at least one operating parameter of the road paver.

Abstract: The invention relates to a steering device for a steerable machine, particularly a construction machine, comprising a steering element for manual input of steering commands, a steering actuator for driving a steering adjustment of a travel unit of the construction machine, and a transmission device, which is arranged between the steering element and the steering actuator, the transmission device including an actuator orbitrol for driving the steering actuator. Furthermore, the invention relates to a construction machine having such a steering device, as well as to a method for steering a steerable machine, particularly a construction machine.

Abstract: A hydraulic control arrangement for activating a double-acting actuating cylinder, which is connected on the piston side to a road finisher and on the piston-rod side to a screed of the road finisher, is provided. The hydraulic control arrangement includes a supply connection, a tank connection and two consumer connections, in which a loading pressure or a relief pressure is applied to the piston of the actuating cylinder via the consumer connections. The loading pressure or relief pressure is controlled as a function of a defined operating state, and, in a controlling-the-screed-load operating state, the relief pressure supplied to the actuating cylinder on the piston-rod side is controlled via a proportional pressure control valve.

Abstract: The present invention relates to a device and method for ascertaining the steering angle (?3) of at least one steerable wheel of a set of steerable wheels of a machine that can be directionally controlled, which machine comprises at least said set of steerable wheels and at least one set of drivable wheels showing a specific wheelbase (a1) relative to said steerable wheels and spaced from one another by a specific track width (b1), wherein by means of an ascertained wheel velocity difference of the two driven wheels a yaw rate (?) and a real circle radius (r1) of the driven wheel on the inside of the curve are ascertained. It is then possible to ascertain the steering angle (?) from these values by way of the geometrical relationship of wheelbase (a1) and track width (b1) of the machine.

Abstract: The present invention relates to a method for operating a hydraulic system of a self-propelled road paver, in particular, for the supply of hydraulic oil as needed to a closed hydraulic circuit of the road paver, a hydraulic system of a road paver for performing the method and a road paver having such a hydraulic system. The extraction and/or return of the quantity of hydraulic oil occur depending on at least one operating parameter of the road paver.

Abstract: The invention relates to a self-propelled construction machine, for example, a road finisher, comprising a vehicle chassis and having a tandem axle unit and a single wheel on each side of the vehicle, wherein each tandem axle unit comprises a twin axle carrier and also a regulating device, by means of which the twin axle carrier can be pivoted relatively to the vehicle chassis. Each tandem axle unit is mounted on a lever arm, which is mounted for rotation about a pivot axle on the vehicle chassis, and which is engaged by the regulating device.

Abstract: The present invention relates to a device and method for ascertaining the steering angle (?3) of at least one steerable wheel of a set of steerable wheels of a machine that can be directionally controlled, which machine comprises at least said set of steerable wheels and at least one set of drivable wheels showing a specific wheelbase (a1) relative to said steerable wheels and spaced from one another by a specific track width (b1), wherein by means of an ascertained wheel velocity difference of the two driven wheels a yaw rate (?) and a real circle radius (r1) of the driven wheel on the inside of the curve are ascertained. It is then possible to ascertain the steering angle (?) from these values by way of the geometrical relationship of wheelbase (a1) and track width (b1) of the machine.

Abstract: The invention relates to a self-propelled construction machine, for example, a road finisher, comprising a vehicle chassis and having a tandem axle unit and a single wheel on each side of the vehicle, wherein each tandem axle unit comprises a twin axle carrier and also a regulating device, by means of which the twin axle carrier can be pivoted relatively to the vehicle chassis. Each tandem axle unit is mounted on a lever arm, which is mounted for rotation about a pivot axle on the vehicle chassis, and which is engaged by the regulating device.

Abstract: A road paver for laying road construction material comprises a tamping beam, a bunker for receiving road construction material, a wheeled chassis with a rear axle and a steerable front axle, and a hydraulic arrangement for permanent or optionally selectable drive of hydraulic motors which are coupled to the front wheels. A method for tractive power control and for drive slip limitation of the front drive of a road paver is also disclosed.

Abstract: A road paver for laying road construction material comprises a tamping beam, a bunker for receiving road construction material, a wheeled chassis with a rear axle and a steerable front axle, and a hydraulic arrangement for permanent or optionally selectable drive of hydraulic motors which are coupled to the front wheels. A method for tractive power control and for drive slip limitation of the front drive of a road paver is also disclosed.

Abstract: The invention relates to a process for releasing at least one spring accumulator brake (10), which is operated by a pressure medium and which is connected to a brake-release-pressure-supply-circuit (63) in normal operation for impact with a brake release pressure and which, in service operation, is detached from the circuit (63) in case of failure of the brake release pressure and is released through a pressure medium source (37) against the spring force of the spring accumulator. To develop the process in such a way that the risk of an accident taking place reduces after the brake release pressure has failed, it has been proposed in the invention that at least one brake (10) gets re-connected automatically with the circuit (63) when the brake release pressure is provided again. Further, an apparatus and a hydraulic circuit for carrying out the process are proposed.

Abstract: A hydraulic control arrangement for activating a double-acting actuating cylinder, which is connected on the piston side to a road finisher and on the piston-rod side to a screed of the road finisher, is provided. The hydraulic control arrangement includes a supply connection, a tank connection and two consumer connections, in which a loading pressure or a relief pressure is applied to the piston of the actuating cylinder via the consumer connections. The loading pressure or relief pressure is controlled as a function of a defined operating state, and, in a controlling-the-screed-load operating state, the relief pressure supplied to the actuating cylinder on the piston-rod side is controlled via a proportional pressure control valve.

Abstract: The invention relates to a process for releasing at least one spring accumulator brake (10), which is operated by a pressure medium and which is connected to a brake-release-pressure-supply-circuit (63) in normal operation for impact with a brake release pressure and which, in service operation, is detached from the circuit (63) in case of failure of the brake release pressure and is released through a pressure medium source (37) against the spring force of the spring accumulator. To develop the process in such a way that the risk of an accident taking place reduces after the brake release pressure has failed, it has been proposed in the invention that at least one brake (10) gets re-connected automatically with the circuit (63) when the brake release pressure is provided again. Further, an apparatus and a hydraulic circuit for carrying out the process are proposed.