| 摘要 |
<p>PROBLEM TO BE SOLVED: To optionally supply liquid of high pressure by opening a passage communicating a piston rod with a conduit for operation and closing a passage communicating a second chamber with a third chamber before operation of a device, and closing the passage communicating the piston rod with the conduit for operation at operation to project the piston rod to the third chamber in operation of the device. SOLUTION: A piston rod 15 is integrated with a piston 1, a passage 12 in an open state is engaged to a passage 13 before operation, and a communicating state between a second chamber 9 and a third chamber 11 is cut off. When oil supplied to a conduit 6 for operation has a pressure not more than a predetermined pressure, a passage 16 is closed, and the piston 1 does not operate. The third chamber 11 supplies oil through passage 12, 13, 14. When the oil pressure is increased and exceeds the predetermined pressure, a valve element 17 moves to open the passage 16, and the oil in the conduit 6 for operation flows into a first chamber 7 via the passage 16, 18, 24 to move a piston 1 and close the passage 12, and the piston rod 15 is projected to the third chamber 11. Accordingly, high pressure oil can be supplied optionally as required.</p> |
