| 摘要 |
A drop rod 14 pivotally connected to an operating lever 13 of a louvre window by a lug 19 is normally retained in its raised position by an electromagnet 16 which engages a keeper plate 15 on the drop rod. When the electromagnet is de-energised, for example upon the detection of gas or smoke, the drop rod 14 falls under gravity and opens the window, the rod being guided in its falling movement by a guide 20. The positions of keeper plate 15, lug 19 and guide 20 are all variable so that they can be adapted to different sizes of windows whilst making use of standardised components. Where the window includes more than one operating lever 13, the guide 20 can be dispensed with and the drop rod 14 can instead be secured to all of the operating levers. <IMAGE> |
