| CPC E02F 9/22 (2013.01) [E02F 9/20 (2013.01); E02F 9/2228 (2013.01); E02F 9/2235 (2013.01); F15B 11/02 (2013.01); F15B 11/028 (2013.01); F15B 11/042 (2013.01); F15B 11/044 (2013.01); F15B 21/087 (2013.01); E02F 9/2296 (2013.01); F15B 2211/20546 (2013.01); F15B 2211/327 (2013.01); F15B 2211/351 (2013.01); F15B 2211/353 (2013.01); F15B 2211/365 (2013.01); F15B 2211/40515 (2013.01); F15B 2211/41509 (2013.01); F15B 2211/426 (2013.01); F15B 2211/455 (2013.01); F15B 2211/46 (2013.01); F15B 2211/6309 (2013.01); F15B 2211/6313 (2013.01); F15B 2211/6346 (2013.01); F15B 2211/6655 (2013.01)] | 3 Claims |
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1. A work machine comprising:
a fluid pressure actuator that operates a driven body by being driven by supply and discharge of working fluid;
a pump that supplies the working fluid to the fluid pressure actuator;
a meter-in control valve capable of controlling a flow rate of the working fluid supplied from the pump to the fluid pressure actuator;
a meter-out control valve capable of controlling a flow rate of the working fluid discharged from the fluid pressure actuator;
an operation device that outputs an operation signal giving an instruction for driving of the fluid pressure actuator; and
a controller that controls the pump, the meter-in control valve, and the meter-out control valve,
the controller being configured to
compute a target velocity of the fluid pressure actuator according to the operation signal from the operation device,
compute target thrust or target torque of the fluid pressure actuator on a basis of a driven state of the fluid pressure actuator, and
control a velocity of the fluid pressure actuator by the meter-out control valve on a basis of the operation signal from the operation device and control at least one of the pump and the meter-in control valve such that a pressure on a meter-in side of the fluid pressure actuator is equal to or higher than a predetermined value, in a case a positive or negative sign of the target velocity as a computation result is different from a positive or negative sign of the target thrust or the target torque as a computation result,
the work machine comprising:
a first pressure sensor that senses a delivery pressure of the pump; and
a second pressure sensor that senses the pressure on the meter-in side of the fluid pressure actuator, wherein
the controller is configured to compute the target thrust or the target torque on a basis of the target velocity as a computation result, and
the controller is configured to, in a case the positive or negative sign of the target velocity as a computation result is different from the positive or negative sign of the target thrust or the target torque as a computation result,
set a meter-in target pressure as a target value of the pressure on the meter-in side of the fluid pressure actuator to the predetermined value or higher,
compute a meter-out target pressure as a target value of a pressure on a meter-out side of the fluid pressure actuator on a basis of the target thrust or the target torque as a computation result and the set meter-in target pressure,
control the meter-out control valve by using the meter-out target pressure as a computation result,
control the pump on a basis of the set meter-in target pressure and a sensed value obtained by the first pressure sensor, and
control the meter-in control valve on a basis of the set meter-in target pressure and a sensed value obtained by the second pressure sensor.
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