A hydrostatic steering device for an agricultural utility vehicle including a steering orbitrol, which can be controlled via a steering handle and by which a dual-action steering cylinder can be extended in accordance with a steering operation occurring at the steering handle. Depending on the operation direction of the steering handle, a first orbitrol connection forms a supply fed from a hydraulic high-pressure source, and a second orbitrol connection forms a return which communicates with a hydraulic reservoir, to actuate opposing working chambers of the steering cylinder. A hydraulic leakage flow occurring between the first and second orbitrol connections can be compensated with regard to a hydraulic operation of the steering cylinder via a valve assembly communicating with the high-pressure source and the hydraulic reservoir.

A steering device includes a control unit that includes a hydraulic abnormality determiner. The hydraulic abnormality determiner is configured to determine a hydraulic abnormality to be present in a pair of liquid chambers of a power cylinder of the steering device, in response to satisfaction of a condition that a total torque of a steering torque measured by a torque sensor and a motor assist torque provided by an electric motor is greater than a predetermined threshold torque. The control unit is configured to increase the motor assist torque in response to satisfaction of a condition that the hydraulic abnormality determiner determines the hydraulic abnormality to be present.

A steering device includes a control unit that includes a hydraulic abnormality determiner. The hydraulic abnormality determiner is configured to determine a hydraulic abnormality to be present in a pair of liquid chambers of a power cylinder of the steering device, in response to satisfaction of a condition that a total torque of a steering torque measured by a torque sensor and a motor assist torque provided by an electric motor is greater than a predetermined threshold torque. The control unit is configured to increase the motor assist torque in response to satisfaction of a condition that the hydraulic abnormality determiner determines the hydraulic abnormality to be present.

The present disclosure relates to redundant steering system, including a first steering knuckle rotatable with respect to a first steering axis, a first steering cylinder, a first steering rod coupled to the first steering cylinder, a second steering cylinder, and a second steering rod coupled to the second steering cylinder. The first steering rod and the second steering rod are each rotatably coupled to the first steering knuckle at a distance from the first steering axis and at different positions along the first steering axis.

The present disclosure relates to redundant steering system, including a first steering knuckle rotatable with respect to a first steering axis, a first steering cylinder, a first steering rod coupled to the first steering cylinder, a second steering cylinder, and a second steering rod coupled to the second steering cylinder. The first steering rod and the second steering rod are each rotatably coupled to the first steering knuckle at a distance from the first steering axis and at different positions along the first steering axis.

A hydraulic steering device is provided comprising a supply port arrangement having a supply port (P) and a return port (T), a working port arrangement having two working ports (L, R), direction valve means (2) arranged between said supply port arrangement and said working port arrangement, at least two fluid meters (3, 4), each of said fluid meters (3, 4) having a movable metering element (12, 15), said metering elements (12, 15) being connected by a shaft (5), said shaft (5) having an axis, selector valve means (6) being provided, said selector valve means (6) in a first position arranging said fluid meters (3, 4) hydraulically in parallel and in a second position shutting off one of said fluid meters (3, 4), said selector valve means (6) having a valve element (20) shiftable in an direction parallel to said axis. It is an object to reduce wear in said hydraulic steering device in a simple manner. To this end said selector valve means (6) are arranged between said two fluid meters (3, 4), said shaft (5) extending through said valve element (20).

A hydraulic steering device is provided comprising a supply port arrangement having a supply port (P) and a return port (T), a working port arrangement having two working ports (L, R), direction valve means (2) arranged between said supply port arrangement and said working port arrangement, at least two fluid meters (3, 4), each of said fluid meters (3, 4) having a movable metering element (12, 15), said metering elements (12, 15) being connected by a shaft (5), said shaft (5) having an axis, selector valve means (6) being provided, said selector valve means (6) in a first position arranging said fluid meters (3, 4) hydraulically in parallel and in a second position shutting off one of said fluid meters (3, 4), said selector valve means (6) having a valve element (20) shiftable in an direction parallel to said axis. It is an object to reduce wear in said hydraulic steering device in a simple manner. To this end said selector valve means (6) are arranged between said two fluid meters (3, 4), said shaft (5) extending through said valve element (20).

A hydraulic arrangement for a utility vehicle. In one implementation, the arrangement may include a hydraulic displacement pump and a supply connection as an interface for supplying hydraulic consumers, a displacement control unit dependent on an output pressure of the displacement pump for displacing the displacement pump, a hydraulic auxiliary pump and an auxiliary supply connection as an interface for alternatively supplying at least some of the consumers, and a hydraulic valve unit hydraulically arranged in a throughflow path between a pump output of the displacement pump and the supply connection. The hydraulic valve unit may have a first switching position in which the pump output is hydraulically connected to the supply connection and hydraulically separated from an output of the auxiliary pump, and a second switching position in which the pump output is hydraulically separated from the supply connection and hydraulically connected to the output of the auxiliary pump.

A hydraulic arrangement for a utility vehicle. In one implementation, the arrangement may include a hydraulic displacement pump and a supply connection as an interface for supplying hydraulic consumers, a displacement control unit dependent on an output pressure of the displacement pump for displacing the displacement pump, a hydraulic auxiliary pump and an auxiliary supply connection as an interface for alternatively supplying at least some of the consumers, and a hydraulic valve unit hydraulically arranged in a throughflow path between a pump output of the displacement pump and the supply connection. The hydraulic valve unit may have a first switching position in which the pump output is hydraulically connected to the supply connection and hydraulically separated from an output of the auxiliary pump, and a second switching position in which the pump output is hydraulically separated from the supply connection and hydraulically connected to the output of the auxiliary pump.

A hydraulic arrangement for a utility vehicle. The arrangement may include a hydraulic displacement pump which is connected via a pump output to a supply connection as a hydraulic interface for supplying hydraulic consumers of the utility vehicle. In addition, the device may include a hydraulic auxiliary pump and an auxiliary supply connection as a hydraulic interface for alternatively supplying at least some of the consumers. The device may include a displacement control unit which is dependent on an output pressure of the auxiliary pump for displacing the displacement pump in such a manner that a hydraulic working connection of a displacement cylinder of the displacement control unit is connected to an output of the auxiliary pump.