| 摘要 |
A fire-rated type suspension ceiling grid runner is disclosed having expansion means intermediate its ends which collapse when the runner expands due to elevated temperatures occurring during a fire or the like. The runner provides a boxlike panel supporting flange along the lower end of the web thereof in which slots are formed to define a flange segment and connecting legs. When the expansion means collapses, the flange segment is laterally displaced as a unit and remains connected to each adjacent portion of the boxlike flange by at least two longitudinally spaced legs. The displaced flange segment functions as a bridging beam which continues to connect the adjacent portions of the flange and maintain them in alignment so that a grid formed of the runners can continue to maintain proper support for panel even when fire conditions occur. |
