| 摘要 |
PURPOSE: To facilitate the matching of a ventilating fan cover in size to a ventilating fan by providing collapsed ribs at the corners, and providing stepwise differences between the frame surface of the cover and the rib faces. CONSTITUTION: A collapsed rib 2 is provided at a flexible ventilating fan cover 1, and a stepwise difference α is provided between the frame surface of the cover 1 and the surface of the rib 2. Thus, the cover 1 is placed on a ventilating fan, the inner frame of the cover 1 is collapsed in the outer frame of the fan, and can be snugly matched to the size of the cover 1. Thus, the cover 1 can be easily matched to the size of the fan. |
