Hitachi Construction Machinery Co., Ltd.

Kazuyuki Ito

Tetsuji Tanaka

Isamu Aoki

Masaki Yoshikawa

Kouji Shimazaki

Keisuke Naitou

Koji Hyodo

Takuya Shimomura

Yoshikazu Urimoto

Provided is a work vehicle capable of reducing the fuel consumption while maintaining the working efficiency. A wheel loadercomprising a vehicle body controllerA for controlling an engine, wherein the vehicle body controllerA limits an upper limit rotational speed of the enginebased on an accelerator pedal step-on amount α, a brake pedal step-on amount β, a torque converter speed ratio e which is a ratio of a rotational speed of a torque converter, a discharge pressure Pof a loading hydraulic pump, and a stroke amount Sof lift arm cylindersor a stroke amount Sof a bucket cylinder

Work vehicle

A wheel loaderas a construction machine has a hydraulically driven working deviceand a controllerA for measuring the weight of a load, wherein the wheel loaderincludes a changeover switchas a changeover device for switching whether to measure the weight of the load, and in a case where an attitude of the working devicesatisfies a predetermined load measurement condition, the changeover switchis valid, and pistonsare positioned in a first area provided on one end side or in a second area provided on the other end side, the controllerA limits the command current to be output to lift arm solenoid proportional valvesand the bucket solenoid proportional valves

Construction machine

Provided is a wheel loader capable of reducing erroneous determination of rear wheel lifting. The wheel loaderincludes a controllerfor determining a rear wheel lifting state where rear wheelsB are lifted upwardly. The controlleris configured to, when a temporal change rate α of a bucket operation angle becomes a temporal change rate of a bucket operation angle necessary for a tilt operation of a bucketduring an excavation operation and a temporal change rate β of a vehicle body inclination angle estimated by the controllerbecomes a temporal change rate of an obliquely upward inclination state of a rear vehicle body with respect to a front vehicle body, turn on a correlation flag indicating a correlation between an operation state of the bucketand an inclination state of a vehicle body to determine a rear wheel lifting.

Wheel loader

Provided is a wheel loader capable of exhibiting sufficient excavation performance while suppressing slip during excavation. A control device provided on a wheel loader according to the present invention is configured to determine a reduction value (&#x394;f') of traveling drive force based on first vehicle body acceleration (av) of a vehicle body calculated from acceleration detected by an acceleration sensor, second vehicle body acceleration (av) of the vehicle body calculated from rotational speed of wheels detected by a rotational speed sensor, and thrust (ph) of a hydraulic cylinder detected by a thrust sensor, and reduce the traveling drive force based on the reduction value and output the reduced traveling drive force.

Wheel loader configured to determine a reduction value of a traveling drive force

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 loaderincluding a radiatorand an oil coolercomprises a controllerA configured to determine a clogging continuation state of the radiatoror the oil cooler. The controllerA determines whether clogging is occurring in the radiatoror the oil coolerbased 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 R, Rwhile an engineis operating, and outputs a notification command signal for providing the alarm buzzerand the user management systemwith a command to notify that maintenance is necessary when it is determined that the clogging continues.

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Kobe, Japan

Kazuyuki Ito