PROBLEM TO BE SOLVED: To simplify a fixing structure when fixing an operation arm to an operation shaft for operating an operated part in a work vehicle.SOLUTION: A boss part 48 for rotatably supporting an operation shaft 49 is provided. There is provided an operation arm 50 having a coming-off stop part 50c for inhibiting coming-off of an irregular shape part 49a from irregular shape holes 50a,50b due to being engaged with the irregular shape holes 50a,50b into which the irregular shape part 49a of the end part of the operation shaft 49 is inserted, and an engaged portion 48a of the boss part 48. Due to that the irregular shape part 49a is inserted into the irregular shape holes 50a,50b, and coming-off of the irregular shape part 49a from the irregular shape holes 50a,50b is inhibited by the coming-off stop part 50c, the operation arm 50 is fixed to the operation shaft 49, and the operation shaft 49 is rotated by the operation arm 50.SELECTED DRAWING: Figure 6COPYRIGHT: (C)2020,JPO&INPIT【課題】作業車において、被操作部を操作する操作軸に操作アームを取り付ける場合に、取り付けの構造の簡素化を図る。【解決手段】操作軸４９を回転自在に支持するボス部４８が備えられる。操作軸４９の端部の異形部４９ａが挿入される異形孔５０ａ，５０ｂ、及び、ボス部４８の被係合部４８ａに係合することにより、異形部４９ａの異形孔５０ａ，５０ｂからの抜けを阻止する抜け止め部５０ｃを有する操作アーム５０が備えられる。異形部４９ａが異形孔５０ａ，５０ｂに挿入され、抜け止め部５０ｃにより異形部４９ａの異形孔５０ａ，５０ｂからの抜けが阻止されることより、操作アーム５０が操作軸４９に取り付けられて、操作アーム５０により操作軸４９が回転操作される。【選択図】図６
