Abstract: Provided is a work vehicle capable of reducing the fuel consumption while maintaining the working efficiency. A wheel loader 1 comprising a vehicle body controller 5, 5A for controlling an engine 41, wherein the vehicle body controller 5, 5A limits an upper limit rotational speed of the engine 41 based on an accelerator pedal step-on amount ?, a brake pedal step-on amount ?, a torque converter speed ratio e which is a ratio of a rotational speed of a torque converter 42, a discharge pressure P1 of a loading hydraulic pump 44, and a stroke amount S1 of lift arm cylinders 22 or a stroke amount S2 of a bucket cylinder 24.

Abstract: Provided is a working vehicle capable of increasing lifting operation speed of a working device without increasing cost, even when provided with a circuit configuration that prioritizes a steering operation over a working device operation. A wheel loader 1 comprises a priority valve 451 configured to allow hydraulic oil discharged from a hydraulic pump 41 to flow into a steering drive circuit 43 preferentially over a working device drive circuit 44, and further comprises: an electric steering lever 30; a pair of solenoid control valves 34A, 34B configured to control a steering directional control valve 33; and a controller 5. The controller 5 is configured to control the pair of solenoid control valves 34A, 34B so as to limit operation speed of a steering 3 when determining that an engine 40 is in a low idle state and a lift arm 21 is performing a lifting operation.

Abstract: A wheel loader configured to reduce the traveling distance required for a raise and run operation, and reduce fuel consumption includes: an engine 3; a torque converter 41; a forward and reverse switch 62; a stepping amount sensor 610; an operation amount sensor 73; and a controller 5. The controller 5 determines whether a specific condition for specifying an operation of the lift arm 21 in an upper direction during forward travel of the vehicle body, on the basis of a forward and reverse switching signal, the stepping amount on the accelerator pedal 61, and a pilot pressure Ti pertaining to the lifting operation amount for the lift arm 21. When the specific condition is satisfied, the vehicle speed is limited by reducing the maximum rotational speed of the engine 3 in response to increase in the pilot pressure Ti.

Abstract: Provided is a work machine capable of notifying that maintenance is necessary due to continuation of clogging in a cooling device or decrease in cooling performance. A wheel loader 1 including a radiator 31 and an oil cooler 32 comprises a controller 5, 5A configured to determine a clogging continuation state of the radiator 31 or the oil cooler 32. The controller 5, 5A determines whether clogging is occurring in the radiator 31 or the oil cooler 32 based on outside air temperature AW and cooling water temperature CW or hydraulic oil temperature HW, determines whether the clogging continues based on a clogging occurrence ratio R1, R2 while an engine 30 is operating, and outputs a notification command signal for providing the alarm buzzer 61 and the user management system 62 with a command to notify that maintenance is necessary when it is determined that the clogging continues.

Abstract: 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.

Abstract: Provided is a wheel loader capable of moving up a lift arm in a short time during excavation work. A wheel loader comprises a controller configured to control maximum traction force of the wheel loader and input torque of a working device hydraulic pump, and include a specific condition determination section configured to determine whether a specific condition for specifying excavation work is satisfied, an elapsed time measurement section configured to measure an elapsed time from start of the excavation work, and an input torque control section configured to limit the input torque to a first input torque value when the specific condition is satisfied and increase the input torque from the first input torque value when a second set time elapses from the elapse of a first set time.

Abstract: In an unloaded state of the bucket (3), a control device (30) calculates an unloaded moment (M0) around a hinge pin G from the pressure of the lift arm cylinder that is detected by pressure sensors (15a, 15b), the angle of a lift arm that is detected by a lift arm angle sensor 14, and dimension data extracted from a vehicle body information database (35). In a loaded state of the bucket, the control device calculates a loaded moment (M1) around the hinge pin G from the pressure of the lift arm cylinder, the angle of the lift arm, and the dimension data extracted from the vehicle body information database. The control device calculates the load (W) on the bucket by dividing the difference between the unloaded moment and the loaded moment by the horizontal distance (Lw) between the hinge pin and the gravity center position of the bucket.

Abstract: To curb temperature rises in a control device for a supercharger and extend the life of the control device for the supercharger, a work vehicle includes a variable geometry supercharger with variable boost pressure, and a working device driven by pressure oil discharged from a working hydraulic pump, the work vehicle further including: a supercharger control device adapted to control the supercharger; a temperature detection device adapted to detect temperature of the supercharger control device; and a main control device adapted to limit at least one of maximum rotational speed of an engine and maximum vehicle speed of the work vehicle in case the temperature of the supercharger control device is above a predetermined temperature as compared to case the temperature of the supercharger control device is below the predetermined temperature.

Abstract: A wheel loader configured to reduce a sudden change in vehicle speed caused by an erroneous determination of a raising operation of a lift arm is provided. A wheel loader 1 includes an engine 3, a variable displacement type HST pump 41, a variable displacement type HST motor 42 coupled to the HST pump 41 in a closed circuit, a hydraulic pump for working device 43, a forward/reverse selector switch 62 for switching a forward movement and a backward movement of a vehicle body, a depression amount sensor 610 that detects a depression amount of an accelerator pedal 61, a pressure sensor 73 that detects a discharge pressure Pa of the hydraulic pump for working device 43, and a controller 5. The controller 5 determines whether a specific condition to identify an upward movement of a lift arm 21 during a forward travel of the vehicle body based on a forward/reverse switching signal, the depression amount of the accelerator pedal 61, and the discharge pressure Pa detected by the pressure sensor 73.

Abstract: A work vehicle is provided. The work vehicle is capable of notifying an operator of a state close to overheating of a temperature of a cooling oil that cools a brake device before the temperature overheats. A controller (10) in a work vehicle (100) compares each detection value detected from a brake pressure sensor (26) and a vehicle speed sensor (15) to each threshold (V1, P1, R1) predetermined corresponding to each sensor. The controller (10) outputs a warning command that a temperature of a cooling oil is likely to overheat to a notification device (28) when a state that at least one detection value is equal to or more than the threshold and when a state that at least one detection value is equal to or more than the threshold continues for a first duration (t1) or more.

Abstract: A wheel loader configured to reduce a sudden change in vehicle speed caused by an erroneous determination of a raising operation of a lift arm is provided. A wheel loader 1 includes an engine 3, a variable displacement type HST pump 41, a variable displacement type HST motor 42 coupled to the HST pump 41 in a closed circuit, a hydraulic pump for working device 43, a forward/reverse selector switch 62 for switching a forward movement and a backward movement of a vehicle body, a depression amount sensor 610 that detects a depression amount of an accelerator pedal 61, a pressure sensor 73 that detects a discharge pressure Pa of the hydraulic pump for working device 43, and a controller 5. The controller 5 determines whether a specific condition to identify an upward movement of a lift arm 21 during a forward travel of the vehicle body based on a forward/reverse switching signal, the depression amount of the accelerator pedal 61, and the discharge pressure Pa detected by the pressure sensor 73.

Abstract: Provided is a work machine capable of notifying that maintenance is necessary due to continuation of clogging in a cooling device or decrease in cooling performance. A wheel loader 1 including a radiator 31 and an oil cooler 32 comprises a controller 5, 5A configured to determine a clogging continuation state of the radiator 31 or the oil cooler 32. The controller 5, 5A determines whether clogging is occurring in the radiator 31 or the oil cooler 32 based on outside air temperature AW and cooling water temperature CW or hydraulic oil temperature HW, determines whether the clogging continues based on a clogging occurrence ratio R1, R2 while an engine 30 is operating, and outputs a notification command signal for providing the alarm buzzer 61 and the user management system 62 with a command to notify that maintenance is necessary when it is determined that the clogging continues.

Abstract: Provided is a working vehicle capable of, while reducing fuel consumption, improving traveling performance only when high traveling performance is required. A wheel loader 1 comprises: an engine 3; a variable displacement HST pump 41; a variable displacement HST motor 42 connected to the HST pump 41 through a closed circuit; pressure sensors 72A, 72B configured to load pressure of the HST motor 42; and a controller 5, wherein the controller 5 is configured to, in a case of determining that a load pressure detection value P is included in a predetermined pressure range of greater than load pressure P? corresponding to flat ground traveling and smaller than load pressure P? corresponding to an excavation operation, increase maximum rotational speed of the engine 3 only within the predetermined pressure range.

Abstract: Provided is a working vehicle capable of increasing lifting operation speed of a working device without increasing cost, even when provided with a circuit configuration that prioritizes a steering operation over a working device operation. A wheel loader 1 comprises a priority valve 451 configured to allow hydraulic oil discharged from a hydraulic pump 41 to flow into a steering drive circuit 43 preferentially over a working device drive circuit 44, and further comprises: an electric steering lever 30; a pair of solenoid control valves 34A, 34B configured to control a steering directional control valve 33; and a controller 5. The controller 5 is configured to control the pair of solenoid control valves 34A, 34B so as to limit operation speed of a steering 3 when determining that an engine 40 is in a low idle state and a lift arm 21 is performing a lifting operation.

Abstract: Provide is a loading vehicle capable of quickly operating an object handling device in the upward direction while traveling forward. A wheel loader 1 comprises an engine 3, an HST pump 41, an HST motor 42, a forward/reverse changeover switch 62, a step-on amount sensor 610, a pressure sensor 73, and a controller 5. In a case where a specific condition for specifying lifting operation of a lift arm 21 during forward traveling of the vehicle body is satisfied, the controller 5 increases maximum rotational speed of the engine to a predetermined value Nmax2 which is greater than maximum engine rotational speed Nmax1 during traveling on the flat ground, and limit maximum vehicle speed to a predetermined value Vmax2 which is smaller than maximum vehicle speed Vmax1 prior to the lifting operation of the lift arm 2.

Abstract: Provided is a working vehicle capable of, while reducing fuel consumption, improving traveling performance only when high traveling performance is required. A wheel loader 1 comprises: an engine 3; a variable displacement HST pump 41; a variable displacement HST motor 42 connected to the HST pump 41 through a closed circuit; pressure sensors 72A, 72B configured to load pressure of the HST motor 42; and a controller 5, wherein the controller 5 is configured to, in a case of determining that a load pressure detection value P is included in a predetermined pressure range of greater than load pressure Pa corresponding to flat ground traveling and smaller than load pressure P? corresponding to an excavation operation, increase maximum rotational speed of the engine 3 only within the predetermined pressure range.

Abstract: Provide is a loading vehicle capable of quickly operating an object handling device in the upward direction while traveling forward. A wheel loader 1 comprises an engine 3, an HST pump 41, an HST motor 42, a forward/reverse changeover switch 62, a step-on amount sensor 610, a pressure sensor 73, and a controller 5. In a case where a specific condition for specifying lifting operation of a lift arm 21 during forward traveling of the vehicle body is satisfied, the controller 5 increases maximum rotational speed of the engine to a predetermined value Nmax2 which is greater than maximum engine rotational speed Nmax1 during traveling on the flat ground, and limit maximum vehicle speed to a predetermined value Vmax2 which is smaller than maximum vehicle speed Vmax1 prior to the lifting operation of the lift arm 2.

Abstract: A work vehicle is provided. The work vehicle is capable of notifying an operator of a state close to overheating of a temperature of a cooling oil that cools a brake device before the temperature overheats. A controller (10) in a work vehicle (100) compares each detection value detected from a brake pressure sensor (26) and a vehicle speed sensor (15) to each threshold (V1, P1, R1) predetermined corresponding to each sensor. The controller (10) outputs a warning command that a temperature of a cooling oil is likely to overheat to a notification device (28) when a state that at least one detection value is equal to or more than the threshold and when a state that at least one detection value is equal to or more than the threshold continues for a first duration (t1) or more.

Abstract: The work vehicle includes: a clutch device including a forward-travel clutch and a backward-travel clutch configured to cause, when being in an engagement state, the work vehicle to travel in a forward travel direction and a backward travel direction; a forward-backward travel instruction device configured to instruct the work vehicle to travel in the forward travel direction or the backward travel direction; a clutch state detection device configured to detect whether the forward-travel clutch and the backward-travel clutch are each in the engagement state; and a torque restriction section configured to restrict a maximum absorbing torque of the hydraulic pump to be low when a restriction condition holds, the restriction condition including a condition that a traveling direction of the work vehicle, which corresponds to an engagement state of the clutch device, and a traveling direction of the work vehicle, which is instructed by the forward-backward travel instruction device are opposite to each other.

Abstract: The present invention relates to a work vehicle including an engine, a hydraulic pump, a hydraulic motor to drive wheels, an HST circuit in which the hydraulic pump and the hydraulic motor are connected to each other in the form of a closed circuit, a reducing agent sensor that detects the state of a reducing agent used to clean exhaust gas from the engine, and an engine restrictor that restricts the rotational speed of the engine based on the output from the reducing agent sensor, and the work vehicle further includes a control unit that changes the tilting angle of the hydraulic pump or the hydraulic motor independently of the rotational speed of the engine to a tilting angle associated with minimum travel drive force necessary for self-travel of the work vehicle when the control unit determines that the engine restrictor has restricted the rotational speed of the engine.