초록 ▼

A travel drive apparatus for a hydraulic drive work vehicle and control method therefor, the apparatus including: a travel hydraulic pump driven by the power of an engine; a hydraulic motor that receives discharged oil from the travel hydraulic pump and causes the vehicle to travel; a travel changeo

A travel drive apparatus for a hydraulic drive work vehicle and control method therefor, the apparatus including: a travel hydraulic pump driven by the power of an engine; a hydraulic motor that receives discharged oil from the travel hydraulic pump and causes the vehicle to travel; a travel changeover valve that receives the discharged oil from the travel hydraulic pump, supplies the discharged oil to the hydraulic motor and discharges return oil from the hydraulic motor to a tank, in which the travel drive apparatus comprises; an accelerator for controlling an engine rotational speed; an operation unit for selecting vehicle forward travel, stop, and reverse travel; the travel changeover valve being adapted for receiving signals from the operation unit, switching the discharge oil supplied from the travel hydraulic pump to the hydraulic motor, and controlling vehicle forward travel, stop and reverse travel; a relief valve that regulates pressure for controlling the hydraulic motor when the vehicle has decelerated, positioned between the travel changeover valve and the hydraulic motor; and a pressurizing unit for raising the set pressure at the relief valve controlling the hydraulic motor when the engine rotational speed is increased, while switching the vehicle from forward travel to reverse travel, or from reverse travel to forward travel, so that the work vehicle may switch over from forward to reverse travel; or vice versa, while exhibiting good acceleration performance.

대표청구항 ▼

[What is claimed is:] [1.]acceleration means for controlling an engine rotational speed;operation means for selecting vehicle forward travel, stop, or reverse travel;the travel changeover valve being adapted for switching the discharged oil supplied from the travel hydraulic pump to the hydraulic mo

[What is claimed is:] [1.]acceleration means for controlling an engine rotational speed;operation means for selecting vehicle forward travel, stop, or reverse travel;the travel changeover valve being adapted for switching the discharged oil supplied from the travel hydraulic pump to the hydraulic motor by receiving a signal from the operation means, and controlling vehicle forward travel, stop, and reverse travel;a relief valve disposed between the travel changeover valve and the hydraulic motor, for regulating pressure for controlling the hydraulic motor when the vehicle is decelerated; andpressurizing means for raising set pressure at the relief valve controlling the hydraulic motor when an engine rotational speed is increased and lowering the set pressure at the relief valve controlling the hydraulic motor when the engine rotational speed is decreased, while switching the vehicle from forward travel to reverse travel, or from reverse travel to forward travel.