| 摘要 |
PROBLEM TO BE SOLVED: To provide a gate opening/closing unit capable of suppressing vibration, and simplifying a mechanism, and preventing the occurrence of a failure and a gate facility including the gate opening/closing unit.SOLUTION: The gate opening/closing unit includes: a fluid pressure cylinder 1 configured to project and retreat a rod 24; and a drive shaft configured to be rotated in accordance as the rod 24 is projected and retreated, and a gate is opened and closed according as the drive shaft is rotated. The cylinder 1 includes: front/rear covers 12; a piston 22; and front/rear ports 20 configured to supply and exhaust fluid from the front/rear of the piston 22. Plungers are protrusively formed on the front/rear faces of the piston 22, and recesses 13 into which the plungers are fitted are formed in the covers 12, and the fluid pressure cylinder 1 is constituted so as to be cushioned within the movement limit of the piston 22. The gate opening/closing unit includes: a switching valve 42 configured to switch a circuit for supplying/exhausting fluid from the ports 20; and a difference pressure sensor 41 configured to detect that the piston 22 has reached the front/rear movement limit when a difference between the pressure of fluid in the front/rear recesses 13 and the pressure of fluid at the rear/front of the piston 22 is a predetermined value or more. When it is detected that the piston has reached the movement limit, the circuit is switched by the switching valve 42, and the moving direction of the piston 22 is reversely rotated. |
