Patent ID: 8646263
Filing Date: 2014-02-11
Classification: B60W,B60Y,E02F,F16H

Abstract:
1. A work vehicle comprising: an engine; a variable displacement type hydraulic pump for travel driven by the engine; a variable displacement type hydraulic motor for travel driven by a hydraulic oil ejected from the hydraulic pump for travel; a pressure detecting section configured to detect a the drive circuit pressure which is the pressure of the hydraulic oil fed from the hydraulic pump for travel to the hydraulic motor for travel; an engine controller configured to adjust an output torque from the engine; and a control section configured to increase a displacement of the hydraulic motor for travel when the drive circuit pressure becomes larger than a target pressure determined according to an engine rotational speed, to reduce the displacement of the hydraulic motor for travel when the drive circuit pressure becomes smaller than the target pressure, and to increase the target pressure of the hydraulic motor for travel when changing a matching point of an absorption torque curve of the hydraulic pump for travel with respect to an output torque curve of the engine from a high rotational speed side to a low rotational speed side wherein the target pressure is set by the control section based on a target pressure curve that stipulates the target pressure with respect to the engine rotational speed.