Filter insert of thermoplastically welded nonwoven material

摘要

Filter insert of thermoplastically welded unwoven material is mfd. by a method in which the material is folded to a comblike profile with each outer edge (4, 5) projecting upwards by less than the fold spacing. A sealing strip (8) of width corresp. to the height (7) of the folds is applied along the length on the outer edges and is thermally welded using pressure members (9) supplying energy to the outer edges of the filter material. Welding positions are pressed together during cooling and then the profile is removed and the folded pack is cut to length.