| 摘要 |
PURPOSE: A device for controlling the operation of a door is provided to prevent damage to a door and a door frame by rapidly opening the door and gradually closing the door. CONSTITUTION: A device for controlling the operation of a door is composed as follows. A moving groove(22) is formed in an upper flange(21) of a piston(20) of a cylinder body(10). A packing(28a) is fitted to the moving groove. A first chamber passage(24) is connected to an upper chamber through the moving groove. A second chamber passage is connected to a lower chamber. The cross section of the first chamber passage is different from the cross section of the second chamber passage. A stopper(30) is formed in the piston, and stops the piston when the piston is reached to the other end of the cylinder body. |
