PROBLEM TO BE SOLVED: To provide a working machine capable of performing stable assist action.SOLUTION: An assist mechanism includes: a first cylindrical member and a second cylindrical member that are movable on a same axis； and a lock mechanism that prevents projection of the first cylindrical member from the second cylindrical member, where the first cylindrical member is connected with a second support point and one end of a gas spring, and the second cylindrical member is connected with the other end of the gas spring. Force applied by the assist mechanism in a direction of flipping up the apron, gradually increases within a prescribed angle range where an apron angle increases. At a site where an apron is lowered, the lock mechanism prevents application of force that changes a distance between the second support point and a third support point.SELECTED DRAWING: Figure 5【課題】安定したアシスト動作が可能な作業機を提供すること。【解決手段】同一軸上で移動可能な第１の筒状部材及び第２の筒状部材と、第１の筒状部材が第２の筒状部材から突出することを防止するロック機構とを有し、第１の筒状部材には第２の支点とガススプリングの一端とが接続され、第２の筒状部材にはガススプリングの他端が接続され、アシスト機構がエプロンを跳ね上げる方向に作用する力は、エプロン角度が増加する所定角度範囲内において徐々に増加し、ロック機構は、エプロンが下降した地点において、第２の支点と第３の支点との距離を変化させる力を作用させないようにするアシスト機構を開示する。【選択図】図５
