| 摘要 |
The present invention is provided with a switching valve that is activated in conjunction with a control valve by pilot pressure supplied through a pilot valve, the switching valve switching the action of an operation check valve, and the switching valve being provided with a pilot chamber to which pilot pressure is led, a spool that moves according to the pilot pressure of the pilot chamber, an urging member for urging the spool in a valve-closing direction, a collar detachably mounted to the pilot chamber, and a piston for receiving pilot pressure on the back surface and creating thrust in the spool against the urging force of the urging member, the piston being slideably inserted in the collar. |
