A work vehicle includes an operation apparatus, a transmission having a plurality of gear positions, and a controller configured to control shift of a gear position of the transmission to a gear position equal to or lower than a shift upper limit position based on a vehicle speed of the work vehicle. The controller makes setting to raise the shift upper limit position by one position based on a first operation having been performed onto the operation apparatus. The controller changes the shift upper limit position from a first shift upper limit position immediately before a second operation different from the first operation to a second shift upper limit position based on the second operation having been performed onto the operation apparatus. The second shift upper limit position is higher than the first shift upper limit position by at least two positions.

A speed reducer with a falling-off prevention feature according to an aspect of the disclosure includes: a speed reducer for decelerating rotation from a drive source that generates a rotational force and outputting the decelerated rotation, the speed reducer being mounted to a robot; and a coupling member for coupling the speed reducer to the robot. The coupling member maintains coupling between the speed reducer and the robot irrespective of displacement of the speed reducer relative to the robot.

A wheeled work vehicle includes: a transmission transmitting the rotational power of a traveling hydraulic motor to wheels; a traveling control valve having an interruption position that interrupts supply of hydraulic fluid from a hydraulic pump to the traveling hydraulic motor; a shift changeover valve that shifts the speed stage of the transmission by the position of the shift changeover valve being selectively switched; and a controller that controls the traveling control valve and the shift changeover valve. The controller switches the traveling control valve to the interruption position, then switches the position of the shift changeover valve such that the speed stage of the transmission is shifted to the low speed stage, and switches the traveling control valve from the interruption position to an original position side before the switching in a case where the controller shifts the transmission from the high speed stage to the low speed stage.

The work vehicle 1 includes a main controller 100 that controls a travel driving force and a work driving force. The main controller 100 includes a travel remaining time calculating unit 111 that calculates a remaining time until a target rise/run distance is reached as a travel remaining time t.sub.C, a work remaining time calculating unit 112 that calculates a remaining time until a target arm angle is reached as a work remaining time t.sub.1, a rise/run determining unit 113 that determines whether rise/run is being performed or not, a correction rate setting unit 114 that sets a travel correction rate η.sub.C that adjusts a travel driving torque and a work correction rate η.sub.I that adjusts a work driving torque based on the travel remaining time t.sub.C, the work remaining time t.sub.1, and the rise/run determination flag, and an engine torque distribution calculating unit 115 that calculates a travel driving torque command and a work driving torque command based on the travel correction rate η.sub.C and the work correction rate η.sub.I.

A time period for which an ineffective operation is performed during an excavation work is reduced. A work machine includes a vehicular body, a running wheel rotatably attached to the vehicular body, a work implement operable with respect to the vehicular body, an operation apparatus for operating the running wheel and the work implement, and a controller that controls an operation by the work machine. The controller determines that an ineffective operation in which the work implement does not work is being performed during the excavation work based on an operation command value output from the operation apparatus and notifies an operator of occurrence of the ineffective operation.

A scraper vehicle is described that can contribute, with a relatively simple and low-cost configuration, to shortening of a construction period, reduction of construction cost, and the like without travel being disabled easily. The scraper vehicle includes an auxiliary drive system that supplies, in excavation by the scraper, a driving force to at least part of traveling wheels of the scraper vehicle. The driving force is supplied constantly or in accordance with a travel resistance of the scraper vehicle.

A drive assembly for a work vehicle has a drive housing, including a first housing element forming a reaction member, a drive shaft, a planetary gear set coupled to the drive shaft and configured to selectively rotate an output element. The planetary gear set has an input component, an output component and a reaction component. One or more input clutch arrangements at an input side of the drive assembly are configured to selectively interface with the planetary gear set to effect a rotation speed of the output element. A control clutch arrangement interfaces with the reaction member and the reaction component. The control clutch arrangement is configured to selectively couple and decouple the reaction member from the reaction component to damp a torque increase transmitted to the output element.

A wheel loader is provided that can suppress abrupt change in vehicle speed accompanied by erroneous determination on a lift arm lifting operation. A wheel loader includes: an engine; an HST pump; an HST motor; a forward and reverse switch; a stepping amount sensor; an operation amount sensor; and a controller. The controller determines whether a specific condition for specifying an operation of the lift arm in an upper direction during forward travel of the vehicle body, on the basis of a forward and reverse switching signal, the stepping amount, and a pilot pressure pertaining to the lifting operation for the lift arm. In a case of the specific condition being satisfied, the vehicle speed is limited by controlling the displacement volume of the HST motor in conformity with increase in the pilot pressure.

A system for controlling a machine impeller clutch includes a power source, a transmission unit, an impeller clutch operatively coupling the power source to the transmission unit, and an input device configured to generate a force data signal indicative of a working fluid pressure. An electronic control module in communication with the input device is configured to execute a time-step predictive analytical model for impeller clutch engagement. The electronic control module configured to receive the force data from the input device, determine an impeller clutch engagement value based at least in part on the force data signal and utilizing the time-step predictive analytical model, and cause engagement of the machine impeller clutch according to the impeller clutch engagement value.

A work vehicle includes an engine, a drive wheel, a power transmission mechanism configured to transmit a driving power of the engine to the drive wheel, and a control unit configured to control the power transmission mechanism. The power transmission mechanism has a torque converter including a first clutch, and a second clutch coupled to the torque converter. The control unit controls an oil pressure supplied to the first clutch to a predetermined oil pressure when the second clutch is partially engaged.