A utility vehicle with hydrostatic steering includes a steering wheel which is mechanically separate from the wheels of a vehicle axle, a hydraulic steering control unit via which a hydraulic pressure can be conducted into a hydraulic steering cylinder of a steering device for the wheels according to a rotational movement of the steering wheel, an input angle sensor configured to detect a rotational movement of the steering wheel, an output steering column, which is mechanically separate from the steering wheel, can be rotated via a steering actuator and acts on the hydraulic steering control unit, and a control unit connected to the input angle sensor and to the steering actuator to activate the steering actuator according to sensor signals of the input angle sensor.

A utility vehicle with hydrostatic steering includes a steering wheel which is mechanically separate from the wheels of a vehicle axle, a hydraulic steering control unit via which a hydraulic pressure can be conducted into a hydraulic steering cylinder of a steering device for the wheels according to a rotational movement of the steering wheel, an input angle sensor configured to detect a rotational movement of the steering wheel, an output steering column, which is mechanically separate from the steering wheel, can be rotated via a steering actuator and acts on the hydraulic steering control unit, and a control unit connected to the input angle sensor and to the steering actuator to activate the steering actuator according to sensor signals of the input angle sensor.

A method for operating a steering unit for a commercial vehicle includes a step of transfer or operation of a regulator unit of the steering unit of the commercial vehicle in an inactive operating mode if it is recognized that a driver is not giving a steering requirement and if a vehicle velocity of the commercial vehicle is lower than a predefined threshold value. The method further includes a step of activation of the regulator unit of the steering unit in an active operating mode if it is recognized that the driver is giving a steering requirement or if a vehicle velocity of the commercial vehicle exceeds the predefined threshold value.

A method for operating a steering unit for a commercial vehicle includes a step of transfer or operation of a regulator unit of the steering unit of the commercial vehicle in an inactive operating mode if it is recognized that a driver is not giving a steering requirement and if a vehicle velocity of the commercial vehicle is lower than a predefined threshold value. The method further includes a step of activation of the regulator unit of the steering unit in an active operating mode if it is recognized that the driver is giving a steering requirement or if a vehicle velocity of the commercial vehicle exceeds the predefined threshold value.

An arrangement for operating a load-controlled hydraulic system of an agricultural tractor, includes a hydraulic pump generating a system pressure and having an actuating device to adjust a displacement volume, a hydrostatic vehicle steering system connected to the hydraulic pump and having a steering orbitrol and a first load-indicating pressure, a pressure-regulating valve connected upstream of the steering orbitrol and actuated via a pressure difference decreasing across a throttle element counter to a predetermined restoring force in accordance with the first load-indicating pressure, a second hydraulic consumer connected to the hydraulic pump and feeding a second load-indicating pressure back to a shuttle valve arrangement, which compares and transmits the respectively higher of the first and second load-indicating pressures to the actuating device to adjust the displacement volume, and a pressure-copying valve indirectly feeding back the first load-indicating pressure to the shuttle valve arrangement.

An arrangement for operating a load-controlled hydraulic system of an agricultural tractor, includes a hydraulic pump generating a system pressure and having an actuating device to adjust a displacement volume, a hydrostatic vehicle steering system connected to the hydraulic pump and having a steering orbitrol and a first load-indicating pressure, a pressure-regulating valve connected upstream of the steering orbitrol and actuated via a pressure difference decreasing across a throttle element counter to a predetermined restoring force in accordance with the first load-indicating pressure, a second hydraulic consumer connected to the hydraulic pump and feeding a second load-indicating pressure back to a shuttle valve arrangement, which compares and transmits the respectively higher of the first and second load-indicating pressures to the actuating device to adjust the displacement volume, and a pressure-copying valve indirectly feeding back the first load-indicating pressure to the shuttle valve arrangement.

A vehicular steering system includes a driving wheel, a wheel drive actuator that rotationally drives the driving wheel, a steering operation mechanism that steers the driving wheel, a steering operation actuator that applies a steering operation force that is used to steer the driving wheel to the steering operation mechanism, and a hydraulic circuit that transmits the rotational driving force of the wheel drive actuator to the steering operation mechanism via hydraulic oil as a steering operation force.

A vehicular steering system includes a driving wheel, a wheel drive actuator that rotationally drives the driving wheel, a steering operation mechanism that steers the driving wheel, a steering operation actuator that applies a steering operation force that is used to steer the driving wheel to the steering operation mechanism, and a hydraulic circuit that transmits the rotational driving force of the wheel drive actuator to the steering operation mechanism via hydraulic oil as a steering operation force.

A steering gear mechanism has a steering housing and a steering input shaft. The steering housing is sealed and has a receptacle through which the steering input shaft passes into the steering housing. The receptacle is sealed against the steering input shaft. A first opening is provided on the steering input shaft within the steering housing, and a second opening is provided outside of the steering housing. The first and second openings are in fluid communication with each other.

A work vehicle includes steerable left and right front wheels and steerable left and right rear wheels and a manually operated steering input for steering the wheels through a hydraulic steering circuit connected to left and right front hydraulic actuators configured to steer the left and right front wheels. In order to perform a rear wheel alignment operation, the hydraulic steering circuit is bypassed so that the steering wheel can be used as an input device to steer each of the rear wheels in a steer by wire arrangement for alignment, without steering the front wheels during the alignment process.