A dual-mode active rear-wheel steering device, including: a steering motor, a main shaft, an intermediate gear, a transmission gear, a planetary gear coupling mechanism and a mode switching assembly. An output end of the steering motor is provided with a first input gear. An end of the main shaft drives a first rear wheel to rotate by a two-stage gear transmission system and a first rear-wheel motion conversion mechanism, and the other end of the main shaft drives a second rear wheel to rotate by the planetary gear coupling mechanism and a second rear-wheel motion conversion mechanism. The intermediate gear, the transmission gear and a sun gear of the planetary gear coupling mechanism are provided on the main shaft. The intermediate gear meshes with the first input gear.

A dual-mode active rear-wheel steering device, including: a steering motor, a main shaft, an intermediate gear, a transmission gear, a planetary gear coupling mechanism and a mode switching assembly. An output end of the steering motor is provided with a first input gear. An end of the main shaft drives a first rear wheel to rotate by a two-stage gear transmission system and a first rear-wheel motion conversion mechanism, and the other end of the main shaft drives a second rear wheel to rotate by the planetary gear coupling mechanism and a second rear-wheel motion conversion mechanism. The intermediate gear, the transmission gear and a sun gear of the planetary gear coupling mechanism are provided on the main shaft. The intermediate gear meshes with the first input gear.

A cylinder boot for an axle of an industrial vehicle includes a cylinder boot body, a rod-side fixing portion, a cylinder-side fixing portion, and a detection portion. The cylinder boot covers a cylinder rod of a steering hydraulic cylinder. The cylinder boot body has a contractable portion that is contractable in response to a stroke of the cylinder rod. The rod-side fixing portion is disposed at one end portion of the cylinder boot body and fixed to a distal end portion of the cylinder rod. The cylinder-side fixing portion is disposed at the other end portion of the cylinder boot body and fixed to a cylinder body of the steering hydraulic cylinder. The detection portion is displaced in a direction in which the cylinder rod extends or contracts, and is detected by a detection sensor disposed on the beam axle.

One example provides a ride on air injection machine including one or more steerable wheels, a compressed air system providing compressed air, one or more air inject tines to inject compressed air from the compressed air system into the grounds, and a steering system. The steering system includes a steering wheel, a cylinder coupled to the steerable wheels, the cylinder including opposing internal chambers and being moveable to steer the steerable wheels and a control valve assembly to direct compressed air from the compressed air system to the internal chambers and to bleed compressed air from the internal chambers based on a position of the steering wheel to move the cylinder steer the steerable wheels.

An autonomous steering control unit for a hydraulic steering control system has a pilot selector valve, primary and secondary electro-hydraulic (EH) steering valves, and an output selector valve. In a primary autonomous steering mode, the primary EH steering valve operates to output pilot fluid from the pilot selector valve through the output selector valve to the steering control system to control steering of a work machine while the pilot selector valve and the output selector valve isolate the secondary EH steering valve from the steering control system. In a secondary autonomous steering mode, the secondary EH steering valve operates to output pilot fluid through the output selector valve to the steering control system while the primary EH steering valve is isolated from the steering control system. In alternative embodiments, a load sense selector valve alternately connects an dynamic load sense line to the operative steering valve.

An autonomous steering control unit for a hydraulic steering control system has a pilot selector valve, primary and secondary electro-hydraulic (EH) steering valves, and an output selector valve. In a primary autonomous steering mode, the primary EH steering valve operates to output pilot fluid from the pilot selector valve through the output selector valve to the steering control system to control steering of a work machine while the pilot selector valve and the output selector valve isolate the secondary EH steering valve from the steering control system. In a secondary autonomous steering mode, the secondary EH steering valve operates to output pilot fluid through the output selector valve to the steering control system while the primary EH steering valve is isolated from the steering control system. In alternative embodiments, a load sense selector valve alternately connects an dynamic load sense line to the operative steering valve.

A steering system for controlling an agricultural machine having a pair of front and rear wheels includes a controller and a steer input sensor for detecting a change in an operator steer input corresponding to a steer command. The system includes a displacement input for communicating a motor displacement associated with an operating mode. A primary differential steering system includes a drive motor for operably controlling the pair of front wheels and a secondary steering system controls the pair of rear wheels. The controller determines if the motor displacement is being controlled according to a first motor displacement or a second motor displacement, and outputs a control signal to actuate first and second actuators as a function of the steer command. The control signal includes a rear steering gain that is a function of machine speed and either the first motor displacement or the second motor displacement.

The present invention discloses a drive-by-wire electro-hydraulic steering system based on a double-winding motor and a hybrid control method. The steering system includes a steering wheel (1), a steering column assembly, a road sense assembly, an electro-hydraulic power-assisted module, a double-winding motor power-assisted module (28), a steering control unit, an electromagnetic clutch (8), a steering tie rod (17), a steering trapezoid (13) and steering wheels (12). The steering system can be switched among various steering work modes according to work conditions of a vehicle, meets steering requirements under various work conditions, uses a work mode that two sets of windings of the double-winding motor work at the same time, and has a motor winding redundancy function. When one set of windings fails, the other set of windings can drive the motor to provide power-assisted torque.

A steering device includes: a steering mechanism including a steering shaft, and a transmitting mechanism; and a controller including a first hydraulic passage state judging section, a first electric motor control section, and a second electric motor control section; the first hydraulic passage state judging section configured to judge a state of the hydraulic fluid in a first hydraulic passage in which the hydraulic fluid discharged from the first pump flows, the first electric motor control section configured to control and drive the first electric motor based on a driving state of a vehicle, and the second electric motor control section configured to increase a rotation number of the second electric motor when the first hydraulic passage state judging section judges that a supply of the hydraulic fluid in the first hydraulic passage is deficient.

A steering system for controlling an agricultural machine having a pair of front wheels and a pair of rear wheels includes a controller, an operator steer input for communicating a steer command, a steer input sensor for detecting and outputting the steer command to the controller, a primary differential steering system for operably controlling the pair of front wheels, and a secondary steering system for operably controlling the pair of rear wheels. The secondary steering system includes a first actuator for controlling a first rear wheel and a second actuator for controlling a second rear wheel. The primary differential steering system is controlled based on the steer command. The controller outputs a control signal to operably actuate the first and second actuators at a non-linear steering gain rate as a function of the steer command.