PROBLEM TO BE SOLVED: To provide normal-reverse rotation switching means for a cooling fan provided in a prime motor part of a work vehicle which is advantageous in the aspect of the cost and has an inexpensive structure.SOLUTION: A prime motor part of a work vehicle includes: a normal rotation gear transmission mechanism 5 which receives power from an engine E and suctions the outside air by normally driving a cooling fan 9 to cool the engine a reverse rotation gear transmission mechanism 6 which blows out the inside air by reversely driving the cooling fan 9 to remove the deposit on a dustproof net 10 installed on the outside of a radiator and switching means which can alternatively switch between the normal rotation gear transmission mechanism 5 and the reverse rotation gear transmission mechanism 6.SELECTED DRAWING: Figure 1COPYRIGHT: (C)2018,JPO&INPIT【課題】作業車両の原動部に備える冷却用ファンの正逆転切替え手段として、コスト的に有利で構造的にも安価に実施できるものとする。【解決手段】 本発明は、エンジン(E)からの動力を入力し、冷却用ファン(9)を正転駆動して外気を吸入し前記エンジンの冷却を行う正転ギヤ伝動機構(5)と、前記冷却用ファン(9)を逆転駆動して内気を吹き出しラジエータの外側に備えた防塵網(10)への付着物を除去する逆転ギヤ伝動機構(6)を備え、前記正転ギヤ伝動機構(5)と前記逆転ギヤ伝動機構(6)を択一的に切り替え可能な切替え手段を設ける。【選択図】 図1
