Abstract: A work vehicle includes a hydraulic actuator that changes an actual steering angle, an actual steering angle detecting part, an operating unit that performs a steering operation, a position adjusting control part that controls the position adjusting part based on the actual steering angle, and a steering control part that controls the hydraulic actuator. The operating unit includes a support part, a rotating part supported rotatably by the support part, an operating part supported rotatably by the support part or the rotating part, a biasing part that biases the operating part to a predetermined position with respect to the rotating part, and a position adjusting part that adjusts a rotation angle of the rotating part with respect to the support part. The biasing part may produce various counterforces and may increase or reduce an increasing rate of a counterforce with respect to the relative angle.

Abstract: A wheel loader includes a vehicle body frame, a transmission mechanism, a support section, a movable section, a joystick lever, and an urging mechanism. The transmission mechanism transmits a movement of the vehicle body frame. The support section is fixed with respect to the vehicle body frame. The movable section is connected to the transmission mechanism and is movably supported by the support section. The movement of the vehicle body frame is input to the movable section. The joystick lever accepts an operation to move with respect to the movable section by the operation. The urging mechanism adjusts a movement of the movable section with respect to the support section.

Abstract: A work vehicle includes a hydraulic actuator that changes an actual steering angle, an actual steering angle detecting part, an operating unit that performs a steering operation, a relative angle detecting part, a steering control part, and a position adjustment control part. The operating unit includes an operating part, a support part, a rotating part, a biasing part biasing the operating part to a predetermined position with respect to the rotating part, and a position adjusting part that adjusts the rotating part. The relative angle detecting part detects a relative rotation angle of the operating part with respect to the rotating part. The steering control part controls the hydraulic actuator based on a rotation operation of the operating part. The position adjustment control part sets a torque based on the relative rotation angle and uses the torque to control the position adjusting part based on the actual steering angle.

Abstract: A valve system includes a valve configured to adjust a flow rate of hydraulic fluid in order to steer a work machine, and a control section configured to determine a command signal sent to the valve. The command signal determines a command flow rate of the hydraulic fluid based on a target flow rate corresponding to an input operation command and a change amount in the target flow rate. The control section is configured to control the change amount according to a magnitude of a reversal operation command when receiving the reversal operation command in order to operate the work machine in a direction opposite to a direction in which steering is operating. A work machine includes the valve system, a front frame, a rear frame, an articulate mechanism rotatably connecting the front frame to the rear frame, and a hydraulic actuator.

Abstract: A work vehicle includes a hydraulic actuator that changes an actual steering angle, an actual steering angle detecting part, an operating unit that performs a steering operation, a position adjusting control part that controls the position adjusting part based on the actual steering angle, and a steering control part that controls the hydraulic actuator. The operating unit includes a support part, a rotating part supported rotatably by the support part, an operating part supported rotatably by the support part or the rotating part, a biasing part that biases the operating part to a predetermined position with respect to the rotating part, a position adjusting part that adjusts a rotation angle of the rotating part with respect to the support part, and a rotation angle detecting part configured to detect the rotation angle of the operating part with respect to the support part or the rotating part.

Abstract: An articulated work vehicle has front and rear frames coupled. The work vehicle includes a hydraulic actuator driven by hydraulic pressure to change a vehicle body frame angle of the front frame with respect to the rear frame, a lever rotatable to change the body frame angle, a control valve that controls a flow rate of oil supplied to the hydraulic actuator, and a controller. The controller sets a target angle of the vehicle body frame angle with respect to an input angle of the lever, and controls the control valve such that an actual angle of the vehicle body frame angle matches the target angle of the vehicle body frame angle.

Abstract: A steering device for operating a work vehicle includes a support part, a base member rotatably supported by the support part, a lever rotatably supported by the support part or the base member, a biasing member and a transmission mechanism connecting part. The biasing member is interposed between the lever and the base member to bias the lever to a predetermined position with respect to the base member. The transmission mechanism connecting part configured to be connected to a transmission mechanism configured to transmit rotation based on a rotation angle of a steering shaft of the work vehicle to the base member. A restriction part may restrict rotation of the lever when an angle of the lever with respect to the base member reaches a predetermined angle.

Abstract: A work vehicle includes a hydraulic actuator that changes an actual steering angle, an actual steering angle detecting part, an operating unit that performs a steering operation, a position adjusting control part that controls the position adjusting part based on the actual steering angle, and a steering control part that controls the hydraulic actuator. The operating unit includes a support part, a rotating part supported rotatably by the support part, an operating part supported rotatably by the support part or the rotating part, a biasing part that biases the operating part to a predetermined position with respect to the rotating part, and a position adjusting part that adjusts a rotation angle of the rotating part with respect to the support part. The biasing par may produce various counterforces and may increase or reduce an increasing rate of a counterforce with respect to the relative angle.

Abstract: A work vehicle includes a hydraulic actuator that changes an actual steering angle, an actual steering angle detecting part, an operating unit that performs a steering operation, a relative angle detecting part, a steering control part, and a position adjustment control part. The operating unit includes an operating part, a support part, a rotating part, a biasing part biasing the operating part to a predetermined position with respect to the rotating part, and a position adjusting part that adjusts the rotating part. The relative angle detecting part detects a relative rotation angle of the operating part with respect to the rotating part. The steering control part controls the hydraulic actuator based on a rotation operation of the operating part. The position adjustment control part sets a torque based on the relative rotation angle and uses the torque to control the position adjusting part based on the actual steering angle.

Abstract: A work vehicle includes a hydraulic actuator that changes an actual steering angle, an actual steering angle detecting part, an operating unit that performs a steering operation, a position adjusting control part that controls the position adjusting part based on the actual steering angle, and a steering control part that controls the hydraulic actuator. The operating unit includes a support part, a rotating part supported rotatably by the support part, an operating part supported rotatably by the support part or the rotating part, a biasing part that biases the operating part to a predetermined position with respect to the rotating part, a position adjusting part that adjusts a rotation angle of the rotating part with respect to the support part, and a rotation angle detecting part configured to detect the rotation angle of the operating part with respect to the support part or the rotating part.

Abstract: A controller disables the motion of a steering cylinder brought about by a steering lever when an enabled state is selected via a lever switch and an instruction to start an engine is issued via a main switch.

Abstract: A controller disables the motion of a steering cylinder brought about by a steering lever when an enabled state is selected via a lever switch and an instruction to start an engine is issued via a main switch.

Abstract: An LSI layout includes a logic function section and a series connection array of two MOSFETs, one end of which array is coupled to a power source voltage and the other end of which array is coupled to ground potential. A fixed logic output is produced at a junction point of the two MOSFETs by providing one MOSFET as an enhance-type MOSFET and providing the other MOSFET as a depletion type MOSFET. A logic circuit is provided which is connected with the junction point of the MOSFET array and with the logic section and is operable to couple the output of the logic section to an output side thereof. Two logic sections may be respectively associated with two logic circuits one of which is operable to couple the output of one logic section to an output thereof for its practical use and the other of which is operable not to couple the output of the other logic section to an output side thereof.