PROBLEM TO BE SOLVED: To enhance the working efficiency of a working vehicle by preventing the lowering of an output of an engine.SOLUTION: A radiator (80) is arranged in a region outside an engine (20), a filtering body (12) is arranged in a region outside the radiator (80), a fan (40) is arranged in a region between the engine (20) and the radiator (80), a forward/reverse rotation output hydraulic stepless gear change device (30) which drives the fan (40) by gear-changing a drive force of the engine (20) is arranged, and a cooling state that atmospheric air is sucked to the inside from the outside of the filtering body (12) by forwardly driving the fan (40), and a dust removal state that a wind is blown out to the outside from the inside of the filtering body (12) by reversely driving the fan (40) are switched to each other by gear-change operating the hydraulic stepless gear change device (30). An output of the hydraulic stepless gear change device (30) is maintained in a stopped state until a set condition is established after a start of the engine (20).SELECTED DRAWING: Figure 9COPYRIGHT: (C)2018,JPO&INPIT【課題】エンジンの出力低下を防止して作業車輛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(80)を配置し、ラジエータ(80)の外側の部位に濾過体(12)を配置し、エンジン(20)とラジエータ(80)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(12)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(12)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)が始動されてから設定条件が成立するまで、油圧式無段変速装置(30)の出力が停止状態に維持される構成とする。【選択図】 図9
