PROBLEM TO BE SOLVED: To increase work efficiency of a work vehicle by maintaining combustion efficiency of an engine.SOLUTION: A work vehicle comprises: a radiator arranged at a position outside an engine 20 a filter body arranged at the position outside the radiator a fan 40 arranged at the position between the engine 20 and the radiator and a hydraulic type infinite variable-speed transmission 30 which can drive the fan 40 in both normal and reverse rotation directions by shifting driving force of the engine 20. Through variable speed operation of the hydraulic type infinite variable-speed transmission 30, the work vehicle can be switched between a cooling state to take in external air from an outside of the filter body to an inside thereof with the fan 40 driven in the normal rotation direction and a dust removal state to blow air from the inside of the filter body to the outside thereof with the fan 40 driven in the reverse rotation direction. The work vehicle also has a control device which variably controls a drive speed of the fan 40 in the normal rotation direction in accordance with a load applied to the engine 20.SELECTED DRAWING: Figure 9COPYRIGHT: (C)2017,JPO&INPIT【課題】エンジンの燃焼効率を維持して作業車輌の作業能率を高める。【解決手段】エンジン20の外側の部位にラジエータを配置し、ラジエータの外側の部位に濾過体を配置し、エンジン20とラジエータの間の部位にはファン40を配置し、エンジン20の駆動力を変速してファン40を駆動する正逆転出力可能な油圧式無段変速装置30を設け、油圧式無段変速装置30を変速作動させることで、ファン40を正転駆動して濾過体の外側から内側へ外気を吸入する冷却状態と、ファン40を逆転駆動して濾過体の内側から外側へ風を吹き出す除塵状態とに切換わる構成とし、エンジン20に掛かる負荷に応じてファン40の正転駆動速度を変速制御する制御装置を設ける。【選択図】図9
