Work machine
A work machine includes: a first pump and a second pump that are driven by an engine; a hydraulic actuator driven by a hydraulic working fluid supplied from the first pump; a control valve that controls a flow of the hydraulic working fluid supplied to the hydraulic actuator; a solenoid valve that reduces a pressure of the second pump to generate a pilot pressure for operating the control valve; a controller that controls the solenoid valve; an engine operating section that enables operation for activating the engine; and a rotation speed sensor that senses a rotation speed of the engine. The controller applies a drive current to the solenoid valve to drive the solenoid valve when a current application condition is established, the current application condition including that it is assessed, on the basis of a sensing result of the rotation speed sensor, that the engine is in a stopped state, and including that ON operation of the engine operating section is performed in a state where activation operation is not performed by the engine operating section.
1 . A work machine comprising:
an engine;
a first pump and a second pump that are driven by the engine;
a hydraulic actuator driven by a hydraulic working fluid supplied from the first pump;
an operation device that operates the hydraulic actuator,
a control valve that controls a flow of the hydraulic working fluid supplied from the first pump to the hydraulic actuator;
a solenoid valve that is driven in accordance with operation of the operation device and reduces a pressure of the hydraulic working fluid supplied from the second pump to generate a pilot pressure for operating the control valve;
a controller that controls the solenoid valve;
an engine operating section that enables operation for activating the engine; and
a rotation speed sensor that senses a rotation speed of the engine, wherein
the controller is configured to
assess whether or not a current application condition is established, the current application condition including that it is assessed, on a basis of a sensing result of the rotation speed sensor, that the engine is in a stopped state, and including that ON operation of the engine operating section is performed in a state where activation operation is not performed by the engine operating section, and including that it is assessed that the operation device is being operated, and
apply a drive current to the solenoid valve to drive the solenoid valve when it is assessed that the current application condition is established.
2 . The work machine according to claim 1 , wherein
the controller is configured to
stop application of the drive current to the solenoid valve when it is assessed that the engine is in an in operation state, in a state where it is assessed that the current application condition is established, and the drive current is being applied to the solenoid valve.
3 . The work machine according to claim 1 , wherein
the solenoid valve has a valve body that is stroked between a fully-closed position and a fully-opened position, and
the controller is configured to
apply the drive current to the solenoid valve for a predetermined length of time set in advance to move the valve body to a full stroke position, and keep the valve body at the full stroke position, when it is assessed that the current application condition is established.
4 . The work machine according to claim 1 , wherein
the controller is configured to
apply the drive current to the solenoid valve repeatedly multiple times when it is assessed that the current application condition is established.
5 . The work machine according to claim 1 , wherein
the work machine includes a temperature sensor that senses a temperature of the hydraulic working fluid supplied to the solenoid valve, and
the controller is configured to
increase the drive current to be applied to the solenoid valve or increase a length of time of application of the drive current to the solenoid valve as the temperature of the hydraulic working fluid sensed at the temperature sensor lowers.