A control assembly (20) for overcoming a rotational resistance required to activate supplementary steering force associated with conventional power steering systems. The control assembly (20) includes a shaft (26) subject to rotational resistance via a torsion bar (62). A valve assembly (22) has a first hydraulic circuit (76) that is interchangeable from an unassisted condition (36) to an assisted condition (34) for providing supplementary steering force to a steering gear after the rotational resistance of the torsion bar (22) is overcome by rotating the shaft (26). An actuator (38) includes a second hydraulic circuit (86) interchangeable from an unengaged condition (42) to an engaged condition (40) applying circumferential force on the shaft (26) to overcome the rotational resistance of the torsion bar (62) and rotate the shaft (26) from a non-rotated position thereby activating the supplementary force of the first hydraulic circuit (76).

A work vehicle is articulated with a front frame and a rear frame linked to the front frame. The work vehicle includes a hydraulic actuator, a control valve, an operation member and a force imparting component. The hydraulic actuator is configured to be hydraulically driven to change a steering angle of the front frame with respect to the rear frame. The control valve is configured to control flow of fluid supplied to the hydraulic actuator. The operation member is linked to the control valve and configured to be operated by an operator. The force imparting component is configured to impart an assist force or a counterforce to an operation of the operation member.

A brushless motor includes: a motor rotor; a stator coil section which has a plurality of energization phases, which includes a first stator coil and a second stator coil that are provided to each phase, and which is arranged to generate a magnetic field, and thereby rotate the motor rotor; and a connection switching section configured to switch a connection of the first stator coil and the second stator coil from a serial connection to a parallel connection, or from the parallel connection to the serial connection.

A torsion bar is provided that is easy, quick, and cost effective to manufacture. The torsion bar may extend along an axis and have a first end and a second end that is spaced from the first end. The torsion bar may have an active section positioned between the first and second ends. The active section may also have a length defined along the axis. A cross-section transverse to the axis may define a contour of the torsion bar where the contour may be uniform along the length of the active section. The contour may define at least one of a polygon and a polygon-like shape.

In a steering device of the present invention, an electric motor rotates a steering shaft through a reduction mechanism, and the reduction mechanism and a torque sensor are accommodated in an integrally-structured housing. With this, the present invention can provide a steering device that is capable of suppressing increase in size of the electric motor.

Technical solutions for compensating for lash in a steering system are described. An example method includes determining a rack pressure value based on a driver torque value and a differential pressure across a rack of the steering system. The method also includes determining a compensation friction value based on a position of a handwheel of the steering system and a speed of a vehicle equipped with the steering system. The method also includes computing a pressure value based on the rack pressure value and the compensation friction value. The method also includes generating a torque command using the pressure value, the torque command being added to the driver assist torque for the steering system.

An articulated work vehicle with linked front and rear frames includes a joystick lever, a force imparting component, and a controller. The joystick lever can be moved to an inside or an outside with respect to an operator's seat by being operated by an operator, to change a steering angle of the front frame with respect to the rear frame. The force imparting component is configured to impart an assist force or a counterforce to an operation of the joystick lever by the operator. The controller controls the force imparting component so that an operating force required to move the joystick lever to the outside is different from an operating force required to move the joystick lever to the inside.

An articulated work vehicle with linked front and rear frames includes a joystick lever, a force imparting component, and a controller. The joystick lever can be moved to an inside or an outside with respect to an operator's seat by being operated by an operator, to change a steering angle of the front frame with respect to the rear frame. The force imparting component is configured to impart an assist force or a counterforce to an operation of the joystick lever by the operator. The controller controls the force imparting component so that an operating force required to move the joystick lever to the outside is different from an operating force required to move the joystick lever to the inside.

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 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.