AIR FILTER

摘要

PURPOSE:To extend the life of a filter by processing a sheet-like electret material into a pleat shape and forming air passing spaces in the fold direction of pleats. CONSTITUTION:A sheet-like electret material is subjected to pleat processing to form a chevron-shape spaces piercing in the direction of folds 12. Air is passed through said spaces 13 in parallel to electret along the direction of the folds 12 to collect dust. By this method, pressure loss can be reduced and the length of the spaces 13 in the air passing direction is easily increased to make it possible to largely form the contact area with dust and dust collecting efficiency is made excellent and the life can be extended.