| 摘要 |
PROBLEM TO BE SOLVED: To provide a pollution preventive cover easy to clamp and release an opening end. SOLUTION: The pollution preventive cover 10 comprises a slender cylindrical bag 1 opened at one end. An opening edge of the bag is sewed by a closure yarn 2 over its substantially entire periphery. The yarn 2 is separated from its sewed part at positions approaching to each other, loosely passed at its one end through a clamping tube 3 disposed near the sewed part and introduced from the other end of the tube 3 to an exterior. When the yarn 2 introduced externally from the tube 3 is pulled and the tube 3 is pressed until its one end is strongly contacted with the sewed part, the opening of the bag 1 is clamped by the yarn 2 passed to the sewed part, and the opening is closed. When the tensioned yarn 2 is loosened, the opening of the bag 1 is naturally opened (by an elaticity of the bag 1) or set to an openable state. |
