| 摘要 |
This invention relates to a rolling shutter having a shutter curtain being wound around a winding drum forming n-polygonal winding layers. According to this invention, since a sudden change of a diameter of winding layer is eliminated, the damage and deterioration of the slats are precluded efficiency of winding and unwinding operation is improved, and it becomes easier to put a manual-operated rolling shutter of this type to practical use. The shutter curtain is comprised of slats being connected to each other and each winding layer is comprised of n slats which have the same vertical dimension. When the shutter curtain is being wound around the winding durm, the distance between the center of the winding drum and apexes of winding layers gradually increases by H/n. The distance H is the difference between a radius of a winding layer and that of adjacent winding layer(s). |
