filtration of tobacco from reglable and variable filter and resulting devices

摘要

1446472 Smoke filters A A FAHIR 30 Aug 1973 [4 Sept 1972] 40975/73 Heading A2C A smoke filter adapted for use with a smoking article comprises means defining a smoke passageway which includes at least one filter plug and a cell for conditioning the smoke in a combination providing at least two different degrees of filtration, the cell having at least one smoke passage the cross-section of which may be varied and regulated at the control of the user to provide adjustment of the degree of filtration. As shown in Figs. 1 and 2 filter plugs 5, 6 are separated by cell 7 the deformable walls of which can be used to regulate the cross section and degree of filtration e.g. by twisting. Filter plugs 5, 6 may be constituted in known manner by a ring 13 of plastic or cardboard and filled with a fibrous material 14 e.g. cellulose acetate. The walls of cell 7 may be made from suitable metal coated paper and an air hole may permit observation of the filtration process. Fig. 6 illustrates how wires 18 defining reinforcing ribs may permit coloured regenerated cellulose sheaths to remain separate and distinct from the extension wrapper.