GB1333434A - Apparatus for making cigarette filters - Google Patents

Abstract

1333434 Tobacco-smoke filter manufacture CIGARETTE COMPONENTS Ltd 31 Oct 1970 51906/70 Heading A2C [Also in Division B5] A tobacco-smoke filter element is formed by drawing a cellulose acetate continiuous filament tow, sprayed with droplets of a plasticiser, into rod or cylindrical configuration e.g. by passage through a heated stuffing box (see Division D1), or during steam heating whilst enclosed by a permeable endless belt, and then crimping the rod or cylinder intermittently along its length whilst heated during passage through a four roll crimping nip (see Division B4-5), and then cutting the rod or cylinder into lengths each comprising a number of filters. In the Fig. 1 embodiment, the crimping forms an end portion of a cruciform configuration of ribs 42, within which the filaments are fused together to be of low permeability, and a tapering and cylindrical portion 41 of increased permeability, including grooves 46 and ridges 47 which provide increased area for access of smoke to the filter. The filter may be a rod, or may be hollow between locations 43 and the end 45. In the Fig. 2 embodiment, a filter 53 is attached to a paper wrapped tobacco rod 50 by cork tipping paper 51, and includes the filter element 53 which is hollow and crimped at 54, and is enclosed by a tubular member 57 preventing passage of smoke therebetween. The Fig. 1 embodiment may similarly be incorporated into a cigarette. The filter element of the Fig. 3 embodiment comprises an end 91, to lie adjacent the tobacco, and a mouth end 93, and may either be incorporated in a cigarette similarly to the Figs. 1 and 2 embodiments, or may be wrapped in air permeable or perforated paper when the grooves 94 facilitate the passage of smoke-diluting air to the mouth end 93. In the Fig. 9 embodiment, the tow 1' is formed to a hollow tubular configuration in passage over a mandrel 91 and through a steam heating nozzle 5', and a mixture of fine particles of polyethylene and granules of activated carbon is intermittently introduced into the tube 7', by compressed air injection at a mandrel outlet 92 from a reservoir 93. The tube 7' is crimped to form ends in the manner of the Figs. 1 and 2 embodiments, with intermediate cylindrical portions containing a polyethylene and carbon capsule. The outer tubular member of the filter element may comprise heat sealable paper which is continuously applied by a garniture to the rod or tube issuing from the crimping device, and which is then heat sealed at its overlapping edges. The filter element may alternatively be enclosed by an outer tubular member e.g. by the tipping material attaching the filter to the cigarette, which is applied in a filter cigarette assembly machine.