The present disclosure provides a steering system of an engineering vehicle, and a backhoe loader. The steering system includes: a direction control device, including a steering wheel, a steering cylinder and steerable wheels, the steering cylinder being in transmission connection with the steering wheel and the steerable wheels; a displacement sensor configured to detect a piston displacement of the steering cylinder; a return motor in transmission connection with the steerable wheels to drive the steerable wheels to return to a normal position; and a controller in signal connection with the displacement sensor and the return motor, and configured to output a control signal according to the piston displacement detected by the displacement sensor to manipulate the return motor to drive the steerable wheels to return. The backhoe loader includes the steering system.

A hydraulic steering system, comprising a steering pump and a plurality of digital steering cylinder assemblies Each digital steering cylinder assembly includes a steering cylinder and a digital hydraulic valve configured to selectively communicate a rodless cavity of the steering cylinder with one of the steering pump and a return oil circuit, and communicate a rod cavity of the steering cylinder with the other of the steering pump and the return oil circuit.A controller can be configured to emit a digital pulse signal to a motorand cause the digital hydraulic valve to move towards a first working position or a second working position andA mechanical feedback structure can be configured to be driven by a piston rod of the steering cylinder when the valve core of the digital hydraulic valve moves towards the first working position or the second working position, so as to drive the digital hydraulic valve to return to a neutral position. The system can improve the control precision and the response speed of the steering system.

The present disclosure provides a steering system of an engineering vehicle, and a backhoe loader. The steering system includes: a direction control device, including a steering wheel, a steering cylinder and steerable wheels, the steering cylinder being in transmission connection with the steering wheel and the steerable wheels; a displacement sensor configured to detect a piston displacement of the steering cylinder; a return motor in transmission connection with the steerable wheels to drive the steerable wheels to return to a normal position; and a controller in signal connection with the displacement sensor and the return motor, and configured to output a control signal according to the piston displacement detected by the displacement sensor to manipulate the return motor to drive the steerable wheels to return. The backhoe loader includes the steering system.

A method for operating a steering system for a motor vehicle, wherein the steering system has at least one steering lever and at least one electric motor for shifting the steering lever so as to cause a steering movement in the presence of a steering input, and wherein the electric motor is electrically connected to a current source via cabling. In doing so, it is provided that the electric motor is actuated and an electric current flowing between the current source and the electric motor is measured in order to check an electrical connection between the current source and the electric motor under the condition that there is no steering input present.

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 device is connected to a turning mechanism to which a part of a turning force is applied by a hydraulic mechanism. The steering device includes an electric motor, a rotation angle detector, and a steering control device. The steering control device is configured to acquire a target turning angle which is a target value of a turning angle of turning wheels, to control the electric motor such that a turning angle of the turning wheels reaches the target turning angle, to estimate a delay of an actual turning angle of the turning wheels with respect to the target turning angle based on a delay model with the detected rotation angle as an input, to output delay information, and to correct the target turning angle based on the delay information.

A motor control device controls an electric motor in a steering system including a hydraulic mechanism that applies a part of a turning force to a turning mechanism and the electric motor that applies the other part of the turning force. The motor control device includes: an actual turning angle acquiring unit configured to acquire an actual turning angle of turning wheels; a target turning angle acquiring unit configured to acquire a target turning angle which is a target value of a turning angle; a control value generating unit configured to generate a motor control value for controlling the electric motor such that the actual turning angle reaches the target turning angle; and an instruction value calculating unit configured to generate an instruction value which is obtained by filtering a natural frequency of the steering system in response to the motor control value.

A steering device is connected to a turning mechanism to which a part of a turning force is applied by a hydraulic mechanism. The steering device includes an electric motor, a rotation angle detector, and a steering control device. The steering control device is configured to acquire a target turning angle which is a target value of a turning angle of turning wheels, to control the electric motor such that a turning angle of the turning wheels reaches the target turning angle, to estimate a delay of an actual turning angle of the turning wheels with respect to the target turning angle based on a delay model with the detected rotation angle as an input, to output delay information, and to correct the target turning angle based on the delay information.

A steering gear assembly, which utilizes a manually-drive first rotatable input shaft coupled with a rotatable valve member to control flow of hydraulic fluid to different downstream passages, includes a torsion tube and a transfer shaft extending within the interior of the torsion tube, with the transfer shaft being configured to receive rotational force from a second rotatable input shaft coupled to a motor or another mechanical torque-supplying element. The torsion tube applies a rotational restoring force to the rotatable valve member. A removable end cover for a steering gear assembly housing includes a rotary seal permitting rotation of the transfer shaft and/or second rotatable input shaft, with the first and second rotatable input shafts opposing one another. A remanufacturing kit for a steering gear assembly includes a torsion tube, a transfer shaft, and an end cover as mentioned. A method for remanufacturing a steering gear assembly is further provided.

A stroke sensor is provided with two disk-shaped rotors configured to rotate with a stroke of a measuring object, a rotation detecting unit that detects rotations of the two rotors, respectively, and a stroke position detecting unit that detects the stroke position of the measuring object based on the rotations of the two rotors detected by the rotation detecting unit. At least one of the two rotors is in direct contact with the measuring object. The two rotors are provided side by side in an arrangement direction perpendicular to an axial direction of the measuring object and are provided so as to be adjacent to the measuring object in an arrangement perpendicular direction perpendicular to the axial direction and the arrangement direction. Each of the two rotors is provided in such a manner that its rotation axis direction is inclined with respect to the arrangement direction.