Patent ID: 8126621
Filing Date: 2012-02-28
Classification: B60W,E02F,F02D,F04B,Y10T

Abstract:
1. An engine load control device of a work vehicle in which an output of an engine is transmitted to driving wheels and is transmitted via a variable displacement type hydraulic pump to a hydraulic actuator, the engine load control device of a work vehicle comprising: a target rotational speed detecting portion configured to detect a target rotational speed of the engine based on a command from a rotational speed directing device configured to control a rotational speed of the engine; an actual rotational speed detecting portion configured to detect an actual rotational speed of the engine; a control portion configured to reduce maximum absorbing torque of the variable displacement type hydraulic pump according to a difference between the target rotational speed of the engine and the actual rotational speed of tile engine; and a variation rate calculating portion configured to calculate a variation rate indicative of a variation amount per unit time of the difference between the target rotational speed of the engine and the actual rotational speed of the engine, the control portion being further configured to adjust a reduction range of the maximum absorbing torque of the variable displacement type hydraulic pump according to a magnitude of the variation rate calculated by the variation rate calculating portion such that the larger the variation rate is, the smaller the reduction range is, the control portion is configured to calculate the variation rate each time a predetermined period of time elapses; and, when the variation rate is not less than a predetermined threshold value, the control portion is configured not to perform adjustment of the maximum absorbing torque of the variable displacement type hydraulic pump.