PROBLEM TO BE SOLVED: To provide a forward/backward switching operation device which is operated by one hand, prevents improper operations, and is excellent in operability by allowing an almost simultaneous operation of a forward/backward switching lever and a cancelling lever while an improper operation prevention mechanism for checking a backward operation is provided in the vicinity of the forward/backward switching lever, and a checking member and the cancelling lever are provided on the improper operation prevention mechanism.SOLUTION: In a forward/backward switching operation device for a farm working machine where a forward/backward switching lever 14 for switching a forward/backward switching device 28 between forward travelling and backward travelling is provided on one right and left side of an operation handle 8, an improper operation prevention mechanism 40 for checking the switching to a backward position by the operation of the forward/backward switching lever 14 is provided on the same side of the operation handle 8, and the improper operation prevention mechanism 40 is provided with a checking member 41 for checking rotations of the forward/backward switching lever and a cancelling lever 42 for cancelling the checking to achieve the simultaneous operations of the forward/backward switching lever 14 and the cancelling lever 42 by one hand.SELECTED DRAWING: Figure 9COPYRIGHT: (C)2018,JPO&INPIT【課題】前後進切換レバーの近傍に後進操作を牽制する誤操作防止機構を設け、誤操作防止機構は牽制部材と解除レバーを備えて、前後進切換レバーと解除レバーをほぼ同時に操作できるようにして、片手でも操作できて、誤操作を防止できるとともに、操作性も良好な前後進切換操作装置を提供しようとする。【解決手段】操作ハンドル８の左右一側に、前後進切換装置２８を前後進に切換える前後進切換レバー１４を設けた農作業機の前後進切換操作装置において、前後進切換レバー１４の操作による後進位置への切換を牽制する誤操作防止機構４０を操作ハンドル８の同じ側に設け、誤操作防止機構４０は、前後進切換レバーの回動を牽制する牽制部材４１と、牽制を解除する解除レバーを設け４２を設け、片手で前後進切換レバー１４の操作と、解除レバー４２の操作とを同時に操作可能に構成した。【選択図】図９
