| 摘要 |
PROBLEM TO BE SOLVED: To provide a control device for a quick coupler of a work machine, with which a lock cylinder may be pressurized to a locked state all the time except when replacing a work tool, and an erroneous operation to bring the lock cylinder to the locked state may be prevented when replacing the work tool.SOLUTION: An electromagnetically-switched first directional control valve 15ES1 is connected to a locked side chamber 15LO of a lock cylinder 15CY fitted on a quick coupler, through a pilot-operated first check valve 15CV1. A pilot-operated second check valve 15CV2 is connected to an unlocked side chamber 15AN of the lock cylinder 15CY, and an electromagnetically-switched second directional control valve 15ES2 is connected between the second check valve 15CV2 and the first directional control valve 15ES1. The first directional control valve 15ES1 and the second directional control valve 15ES2 are controlled by a mode change-over switch 33 and a controller 32 that processes signals from a first sensor 35 that detects bucket closing operation pressure and a second sensor 37 that detects bucket closing working pressure. |
