| 摘要 |
PURPOSE:To improve the dust arresting efficiency of a dust arresting hood used in a plant or the like, by securing to a collecting cylinder two rigid support members having a width to face each other, and arranging thereto opening plates transversely stretchably like a shutter of a camera. CONSTITUTION:The rigid support members 2, 3 having a width are secured to the collecting cylinder 1 of a light-weight material such that the members 2, 3 are faced each other to form an opening in their longitudinal direction, the opening plates 4 for varying the opening are positioned between the rigid support members 2, 3 with their opposite sides overlapped so that they are stretched transversely like a shutter of a camera, and their lower ends are bent outward to form bent sections 7. In addition, a ring (not shown) for retaining an opening is provided to the inside or the outer circumferential section of the opening plates 4. According to this arrangement, the opening of the opening plates 4 can be adjusted in accordance with the situation of the smoking area to exert effectively the dust collecting capacity. |
