Patent GB-1305900-A (GB)
IPC: A24C5/18
Filed: 1969-04-02
Abstract: 1305900 Cigarette making-machines MOLINS MACHINE CO Ltd I April 1970 [2 April 1969] 17135/69 Heading A2C In a method of making cigarettes including a filler consisting of an outer annulus of tobacco surrounding a core of tobacco or other material different from that in the outer annulus, a core of the desired core material is incorporated in the filler while the filler is being built up from a continuous supply of tobacco particles so as to completely surround the core and form an annulus of tobacco adjacent to the wrapper of the cigarette which is subsequently secured around the filler. Suitable core materials are low grade tobacco, reconstituted tobacco, a mixture of tobacco dust and shredded tobacco and other low quality tobacco, and a non tobacco material such as a tasteless cellulose. A number of suitable apparatuses are disclosed. In one embodiment, Figs. 1, 2, 4, a tobacco filler is built up on an air pervious suction band 10 which travels along the top of a narrow chimney having side walls 11, 12 and end walls 13, 14 and, after passing a trimmer 15, is forwarded on a paper web 17 to a garniture 16. The chimney is divided into compartments 23, 25, 26, 29 by internal walls 20, 21, 22. In the first compartment 23 shredded tobacco is fed upwardly to form an initial layer 24 of tobacco on the band 10. Air alone flows in the second compartment and firms the layer 24 on the band 10. In the third compartment 26, core material is fed upwardly to form a narrow layer 27, the top of the side walls 11, 12 of the chimney being constricted by inwardly projecting parts 28 within this chamber. Finally, further shredded tobacco is fed upwardly in the fourth and largest compartment 29 to complete the enclosure of tobacco around the core 27 by forming side portions 30 and a complete layer portion 31. The outer part 19 of the portion 31 is subsequently removed by the trimmer 15 and part or all of this trimmed off portion 19 is preferably fed to the bottom of the compartment 23 to form the initial layer 24. Instead of, or in addition to, compartment 25, the suction applied to the band 10 above compartment 23 may be increased. The walls 20, 21, 22 may be dispensed with relying on straight air flow paths to preserve the separation of the shredded tobacco and core material streams. An inverted arrangement may be used whereby tobacco is showered downwards under gravity with or without air assistance. In a second embodiment, Fig. 5, a suction band 32 moves along the top of a chimney up which tobacco particles are carried by air, the chimney having two compartments 33, 34. In compartment 33 a layer (35) of shredded tobacco is built up on the band 32. Between compartments 33, 34 a preformed continuous core rod 36 is fed through stationary guides 37, 38 onto the layer (35) and continues through compartment 34 where further shredded tobacco is fed to completely enclose the core rod 36. The core rod 36 may be extruded from a reconstituted tobacco dust and shreds mixture. Alternatively an inverted arrangement may be used in which the tobacco is showered downwards under gravity. In a modification, the continuous core rod 36 is replaced by spaced pre-cut sections of core rod, slightly shorter in length than a cigarette length, and the spaces between adjacent sections are completely filled with shredded tobacco. The continuous cigarette rod subsequently formed is cut between the core sections to produce cigarettes in which the core is concealed at either end. Where filter cigarettes are to be made, double length core sections are used, the cut cigarettes each having one "good" end and one end in which the core is exposed and which latter end is subsequently united to a filter. In a third embodiment, Fig. 9, a band 56 moves along the bottom of a shoot 58 down which good tobacco is showered (preferably aided by suction applied through the band 56) to build up an initial layer 60 of which the edges are turned up slightly by means of forming rails (62). The band 56 then passes round a pulley 68 where the cross-sections of the forming rails (62) change shape progressively to reduce the width of the layer 60 and bend its edges further outwards to form approximately a U-shape aided by centrifugal force and by a forming needle 72 that holds the middle section of the layer 60 against the band 56. A core is simultaneously formed for insertion into the U by showering core material up a chimney 74 to build up a core stream 75 on the underside of a suction-backed airpervious band 76, trimming the stream at 78 and transfer transferring it to a tape 80 under a scraper 84 that extends as a tongue which compresses the core stream 75 into an oval crosssection. The compressed core is then fed into the U of the layer 60 and further tobacco is fed up a chimney 70 to complete the formation of a core containing filler. The chimney 70 includes a partition 88 to the right of which tobacco shorts are fed and to the left of which the final layer of good tobacco is fed, but the feed of shorts may be omitted. In a fourth embodiment, Fig. 12, a carpet of tobacco comprising a narrow strip 46 of core material and a wider strip 47 of good tobacco is carried by a horizontal perforated band 44 and is rolled by the action of air in a stationary inverted trough 45 extending obliquely across the band 44, the air being blown upwards through the band through a channel defined by walls 49, 50 beneath the band. The tobacco carpet travels in the direction of the arrow 48 and is rolled progressively from the left so that the core material ends up in the centre of the roll, the final cigarette filler 52 so formed being held in a compressed state by suction beneath the band. The part of the 44 carrying the unrolled tobacco carpet is underlain by a suction chamber. In a fifth embodiment, Figs. 15, 16, which is a modification of the last embodiment, core material 116 and good tobacco 118 are showered down zones 120, 122 respectively of a narrow shoot 114 onto a suction-backed air pervious band 102 to form a tobacco carpet which is forwarded past an air cell (134) and round a suction drum 128 to continue its travel on the lower run of the band 102. A shutter disc 130 controls the suction supply to that part of the drum 128 beyond the disc 130 in response to the density of the tobacco carpet as detected by the air cell (134), and this in turn controls the width of a strip of tobacco 132 that is discarded due to centrifugal force overcoming the controlled reduced suction at this end of the drum 128. The tobacco carpet on the lower run of the band 102 (Fig. 16) is rolled into a continuous cigarette filler in a trough 104 by compressed air delivered via an inclined nozzle (108), and then fed by a suction wheel 111 to a garniture (110).