GB777250A - Improved apparatus for supporting and conveying web-like materials - Google Patents

Abstract

777,250. Feeding webs. AKTIEBOLAGET SVENSKA FLAKTFABRIKEN. Sept. 28, 1953 [Oct. 8, 1952], No. 26606/53. Class 100(1) An apparatus for supporting and conveying a web 1 comprising distributing means for directing a gaseous medium against both sides of .the web arranged on both sides of the web, is characterized by the lower distributing means having evenly spaced boxes 13, 15, 17, 19 each having a perforated wall facing the web, the spaces between the boxes forming outlet openings for discharging the medium between the boxes, such that before discharge the medium flows parallel to the direction of web feed, while the upper distributing means cause the medium to impinge against the upper side of the web and flow alternately towards the left and right side edge of the web. As shown, the web 1, Fig. 2, is fed in the direction indicated by the arrows 3, 11. The gaseous medium is directed on to the lower side of the web in the direction of the arrows 2, 4, 6, 8, 10, 12, Fig. 1, and on to the upper surface in the direction of the arrows 5, 7, 9. The boxes 13, 15, 17, 19, Fig. 2, are connected ,by means of a duct 20 to a fan 21 which supplies the gaseous medium under pressure to openings 22. Channels 14, 16, and 18 are formed between the boxes 13, 15, 17, 19. Boxes 23, 25, 27, 29 facing the upper side of the web are connected by a duct 30 to a fan 31, the boxes being spaced apart to form passages a, b, c, d. One end of the upper boxes is extended down to the web, while a passage g is formed at the opposite end wall between the upper boxes and the web. The medium supplied by the upper boxes, is forced through apertures 32 and is then directed to flow transversely of the web by walls extended downwardly from alternate upper boxes. The medium supplied to the lower side of the web flows along the web in the direction of web feed and is discharged at l, Fig. 5, through the channels 14, 16 and 18 to the fan 21, Fig. 2; or if not to be recirculated is discharged in the direction m, Fig. 5. In a modification, Fig. 4, not shown, for use with wide webs the number of apertures 32 is reduced, a group of such apertures being positioned adjacent a group of discharge apertures connected to channels in the upper boxes which are parallel to the direction of web feed to provide a transverse flow of the medium.