| 摘要 |
The system (1) has a window frame (2) associated to a wall or a ceiling and made of flat folded metal sheet. An invisible connection unit (6) is invisible from a visible surface of the system and connects an opening plate (5) to the frame for defining a releasable obstacle connection between the plate and the frame, in a closed position of the plate, where the plate prevents an access through the frame in the closed position. The plate has a covering unit (7) that covers the frame to mask the frame from the visible surface of the system in the closed position. |
