GB1390313A - Device for stretching a sheet or strip of material - Google Patents

Abstract

1390313 Flattening tobacco leaves AMF INC 21 Feb 1973 [10 March 1972] 8543/73 Heading A2C Tobacco leaves, or parts of tobacco leaves such as half leaves, are smoothed by feeding them to the surface of a foraminous member moveable along a path, to which member they are then held by suction while the member moves from a portion of its path of a first width to a portion of a second greater width thus stretching the leaves held thereto. In one embodiment (Figs. 1 to 5 not shown), the foraminous member comprises a cylindrical perforated rubber sleeve mounted by its edges between two opposed support members which are driven about axes inclined to each other so that the sleeve is stretched between a first width and a second, larger width and back to the first width during each revolution thereof. Suction is applied to the underside of the sleeve during the width increasing half of its rotation. The stretched leaves are removed from the sleeve by a suction conveyer at a point closer to the second, larger width of the sleeve than the point thereon where they were transferred thereto. In another embodiment, Fig. 6, the foraminous member comprises a foraminous, stretchable belt 138 mounted as shown over two rollers 142, 142A of different widths. The edges of the belt 138 are shaped to have rim or edge projections which engage rails 140. A suction chamber (139) underlies the upper run of the belt 138. In yet another embodiment, Fig. 9, a pair of suitably angled, suction backed, metal rollers serve as the foraminous member.