WORK MACHINE

To provide a work machine capable of preventing the occurrence of cavitation while realizing speed control of a hydraulic actuator according to an operation of an operating device.SOLUTION: A control device 80 of a work machine calculates a target speed Vt of fluid pressure actuators 20 and 21 in response to an operating signal from an operating device 6, calculates target thrust force Ft or target torque of the fluid pressure actuators 20 and 21 based on the driving states of the fluid pressure actuators 20 and 21, controls the speeds of the fluid pressure actuators 20 and 21 using meter-out control valves 35 and 37 based on the operating signals from the operating device 6 if positive and negative of the target speed Vt of the calculation result is different from the positive and negative of the target thrust Ft or target torque of the calculation result, and controls at least one of a pump 31 and meter-in control valves 34 and 36 so that the pressure on the meter-in side of the fluid pressure actuators 20 and 21 is equal to or higher than a predetermined value.SELECTED DRAWING: Figure 6 【課題】操作装置の操作に応じた油圧アクチュエータの速度制御を実現しつつキャビテーションの発生を防止できる作業機械を提供する。【解決手段】作業機械の制御装置８０は、操作装置６からの操作信号に応じて流体圧アクチュエータ２０、２１の目標速度Ｖｔを演算し、流体圧アクチュエータ２０、２１の駆動状態を基に流体圧アクチュエータ２０、２１の目標推力Ｆｔ又は目標トルクを演算し、演算結果の目標速度Ｖｔの正負が演算結果の目標推力Ｆｔ又は目標トルクの正負と異なる場合には、流体圧アクチュエータ２０、２１の速度を操作装置６からの操作信号を基にメータアウト制御弁３５、３７によって制御すると共に、流体圧アクチュエータ２０、２１のメータイン側の圧力が所定値以上になるようにポンプ３１およびメータイン制御弁３４、３６の少なくとも一方を制御する。【選択図】 図６