PROBLEM TO BE SOLVED: To provide a working machine which can control the lifting or lowering of a lifting or lowering link device to notify an operator that a land-leveling device is not placed at a receiving position when the land-leveling device is not placed at the receiving position, and can avoid dangers such as falling due to the movement or posture change of a working portion to improve the safety of a work for attaching or detaching the working portion when the working portion detached from a travel vehicle body is attached to a vertical link in a state of being supported on a stand.SOLUTION: The working machine is characterized by disposing the stand for supporting the working portion, when the working portion is detached from a travel vehicle body, setting a relation position where the land-leveling device at a lowered work position interferes with the stand, when the working portion is attached to the vertical link (51) in a state supporting the stand, and disposing a control means for controlling the lifting or lowering of the lifting or lowering link device (3) when a detached state-detecting device (79) detects a state that the working portion is detached, and when the land-leveling device is not placed at the receiving position.COPYRIGHT: (C)2011,JPO&INPIT【課題】 整地装置が収納位置でないときは昇降リンク装置の昇降を規制することによって、整地装置が収納位置でないことをオペレータが気づくようにする。また、走行車体から取り外した作業部をスタンドで支持した状態で縦リンクに装着するとき、作業部の移動や姿勢変化による脱落等の危険を回避し、作業部の着脱作業の安全化を図る。【解決手段】 走行車体から取り外したときに作業部を支持するスタンドを設け、スタンドが支持する状態で作業部を縦リンク(51)に装着しようとすると、下動した作業位置にある整地装置と前記スタンドが干渉するが、取り外し状態検出装置(79)により作業部を取り外した状態であることを検出し、且つ整地装置が収納位置でないとき、昇降リンク装置(3)の昇降を規制する制御手段を設ける。【選択図】 図5
