| 摘要 |
1340942 Corrugating fibrous webs CELFIL CO ESTABLISHMENT 29 June 1971 [13 May 1971] 30443/71 Headings D1S and D2B [Also in Division A2] A web of fibrous material is treated to render it suitable for being gathered in the transverse direction into a filter cord which can be subdivided into filter rods for tobacco products, e.g. cigarettes, by first stretching the web in a first direction in a plurality of consecutive parallel areas so that the fibre structure is loosened and then stretching the web in another direction in a plurality of consecutive parallel areas, at least one of the stretched areas being oriented substantially in the longitudinal direction of the web to facilitate gathering the latter while the continuity of the web is preserved despite the stretched areas. As shown in Fig. 1, a paper web 1 passes, from a supply roll 2, between rolls 3, 5 and is moistened with a liquid 4, e.g. water, alcohol or acetone. Alternatively, moistening may be effected by spraying or the use of wet or hot steam. The web passes between intermeshing, but not contacting, rolls 6, 7 provided with transverse ribs for longitudinal stretching and then between intermeshing, but not contacting, rolls 8, 9, 10 provided with annular ribs for longitudinal grooving and transverse stretching of the paper 1. The speed of the rolls 6, 7 is adjusted to that of the drive of the web 1 and the rolls 8, 9, 10 are rotated at a higher speed than the rolls 6, 7 by an adjustable stepup gear, possibly controlled by a feeler bearing on the web 1. If a volatile liquid 4 is used, it may be recovered by a hood 14 and a tube 15. The web 40 passes over guide rollers 11, 12 to a cording machine identical to that shown in Fig. 10 of Specification 1,276,933. Each roll 6, 7 may comprise a hollow core 14 provided with grooves 15 evenly distributed over its circumference in which heating rods 16 in insulating sheaves are arranged. Rings 17 having transverse exterior ribs are slipped over the core 14 and are forced, by a compression spring, against a stop ring 18. In a modification (not shown), the roll 10 is omitted. In further modifications, the rolls 6, 7 are replaced by rolls having ribs similar to a helical gear so that the first stretching is effected in an oblique direction, Fig. 10 (not shown), or by rolls which form stretched areas lying in two oblique directions, Figs. 11 and 12 (both not shown). |
