Hitachi Construction Machinery Co., Ltd.

Hironao Suzuki

Koji Hyodo

Tetsuji Tanaka

Isamu Aoki

Koji Shimazaki

A wheel loader configured to reduce the traveling distance required for a raise and run operation, and reduce fuel consumption includes: an engine; a torque converter; a forward and reverse switch; a stepping amount sensor; an operation amount sensor; and a controller. The controllerdetermines whether a specific condition for specifying an operation of the lift armin 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, and a pilot pressure Ti pertaining to the lifting operation amount for the lift arm. When the specific condition is satisfied, the vehicle speed is limited by reducing the maximum rotational speed of the enginein response to increase in the pilot pressure Ti.

Wheel loader

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 loaderincludes an engine, a variable displacement type HST pump, a variable displacement type HST motorcoupled to the HST pumpin a closed circuit, a hydraulic pump for working device, a forward/reverse selector switchfor switching a forward movement and a backward movement of a vehicle body, a depression amount sensorthat detects a depression amount of an accelerator pedal, a pressure sensorthat detects a discharge pressure Pa of the hydraulic pump for working device, and a controller. The controllerdetermines whether a specific condition to identify an upward movement of a lift armduring a forward travel of the vehicle body based on a forward/reverse switching signal, the depression amount of the accelerator pedal, and the discharge pressure Pa detected by the pressure sensor. When the specific condition is satisfied, the controllercontrols a displacement volume of the HST motoraccording to an increase of the discharge pressure Pa, so as to limit the vehicle speed.

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Ibaraki, Japan

Hironao Suzuki