GB890856A - Method of and apparatus for manufacturing longitudinally corrugated webs of paper, carton, cardboard, plastics or the like - Google Patents

Abstract

890,856. Corrugating sheet materials. RUEGENBERG, G. July 8, 1958, No. 21873/58. Class 141 A longitudinally corrugated web of paper, cardboard, sheet plastics &c. is produced by firstly forming a number of coarse-pitched longitudinal arches and then passing each arch through a passage of arched cross-section which is shaped so as to subdivide the coarse arch into corrugations of finer pitch, the height of the coarse arch being decreased in the movement of the web through the passage. The web 1, Fig. 1, passes over a convex guide roll 2, between intermeshing plates 5, 6 mounted on shafts 3, 4, then between circumferentially grooved rolls 12, 13 into the stationary shaping device 18 where the coarse arches are subdivided, and finally between rolls 20, 21 where it is coated with a flat web. The stationary shaping device 18 consists of aligned members 25, Fig. 6, pivotally mounted at 26 and co-operating with a common base-plate 23 to form passages of arched cross-section, Fig. 9, the inlet end of each passage corresponding in shape to one of the coarse arches formed by rolls 12, 13. Longitudinal ribs 38, 39 on the flat surface 35 of the base-plate 23 engage in recesses between ribs 40 on the arched upper surface 36. The central ribs 39 taper until they reach the same height as outer ribs 38 at the outlet end of the passage. In one embodiment the arched surface 36 is gradually flattened towards the outlet end, Fig. 12 (not shown), while the ribs 40 are of constant height. In a second embodiment the arched surface is of constant height while the ribs 40 increase in height continuously towards the outlet end of the passage. The height of the shaft 26 supporting the members 25 is adjustable, and the members 25 are held resiliently against the base-plate by springs 59 between the members 25 and a movable cross-beam 53.