PROBLEM TO BE SOLVED: To provide a lift control device capable of reconfiguring an upper limit according to an intention of an operator as much as possible while avoiding unintentional lowering of a ground working device.SOLUTION: The lift control device includes a height sensor 901 for detecting the height of a ground working device 22 attached to a traveling work device via a lift mechanism 23 and outputting a height detection signal an upper limit control unit 71 for setting the upper limit position of the ground working device on the basis of an operation input signal from an input operation device USD for setting the upper limit and a setting prohibition unit 72 for prohibiting setting of the upper limit position based on the operation input signal and setting the upper limit position to the height of the ground working device according to the height detection signal when the upper limit position set by the operation input signal is lower than the height of the ground working device according to the height detection signal.SELECTED DRAWING: Figure 1COPYRIGHT: (C)2016,JPO&INPIT【課題】不測に対地作業装置が下降することを避けながらも、上限の再設定ができるだけ操作者の意思通りに行われる昇降制御装置を提供する。【解決手段】走行作業車に昇降機構23を介して連結された対地作業装置22の高さを検出して高さ検出信号を出力する高さセンサ901と、上限設定用入力操作デバイスUSDからの操作入力信号に基づいて対地作業装置の上限位置を設定する上限管理部71と、操作入力信号によって設定される上限位置が高さ検出信号に基づく対地作業装置の高さより低い場合、操作入力信号による上限位置の設定を禁止し、上限位置を高さ検出信号に基づく前記対地作業装置の高さに設定する設定禁止部72とが備えられている。【選択図】図1
