GB1211266A - Cigarette making - Google Patents

Abstract

1,211,266. Carding tobacco. M. L. STRYDOM. 16 Dec., 1968 [18 Dec., 1967; 22 May, 1968], No. 59768/68. Heading A2C. Tobacco cut-rag is carded in a method wherein the cut-rag falls freely in countercurrent to a rising stream of air, the velocity of the air stream decreasing constantly towards the top of the path of fall, and wherein the air stream follows a path in which eddy currents are created on either side of the path of fall of the cut-rag. An apparatus for carrying out the above method comprises a vertical conduit which has a cross-sectional area which increases towards the top, a central clear zone for free fall and pockets to either side of this zone in which eddy currents may be created. A suitable apparatus is shown in Fig 1, wherein cut-rag enters the conduit through inlet 16 falls through the clear zone 12, passing an upwardly rising stream of air. The air stream is in the form of eddy currents which are formed by the zig-zag shape of the walls 10, 11. Treated cut-rag is removed via shoot 13 and extractor belt 14. The apparatus also includes means (Figs. 2 and 3, not shown) for delivering the cut-rag to inlet 16 at a constant mass rate. This means comprises a conveyer belt system which passes between plates 26 enabling the dielectric constant of the cut-rag to be determined. The speed of the belt is adjusted so that the average density of the material passing between these plates is constant at a predetermined value. Owing to a possible time lag in such control means, the cut-rag from the plates is delivered to an apron 28 provided with angled lip 29 which further enhances delivery of cut-rag at a constant mass rate.