| 摘要 |
PROBLEM TO BE SOLVED: To hold a moving blade at a certain position even when oil is not supplied. SOLUTION: A moving blade opening/closing mechanism of an axial blower has a connecting rod 11 fixed to a piston 5, supplies oil to one of hydraulic chambers 6a and 6b on the opening side and closing side of a piston 5 via a rotary coupling 1, a supply side oil passage 9a of a spool 2, a supply side oil, passage 10a of a distributing valve 3, and a supply side oil passage 12a in the connecting rod 11 to drive the connecting rod 11 in the axial direction to convert the moving blade 14 to an operation in the opening/closing direction. The mechanism has an oil blocking means 16 that releases return oil from the other of the hydraulic chambers 6a and 6b on the opening side and closing side through a discharge side oil passage 12b in the connecting rod 11, a discharge side oil passage 10b of the distributing valve 3, a discharge side oil passage 9b of the spool 2, and an external communication port 15, and closes when pressure in the supply side oil passage 9a of the spool 2 becomes below a predetermined value to block the external communication port 15.
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