GB2289836A

GB2289836A - Cigarette making machine

Info

Publication number: GB2289836A
Application number: GB9510112A
Authority: GB
Inventors: Paul Davis; John Dawson; Derek Henry Dyett
Original assignee: Molins Ltd
Current assignee: Mpac Group PLC
Priority date: 1994-05-19
Filing date: 1995-05-16
Publication date: 1995-12-06
Anticipated expiration: 2015-05-16
Also published as: GB2289836B; GB9510112D0

Abstract

A cigarette making machine comprises means for showering tobacco onto two suction bands 610, 612 to form tobacco sub-streams of similar width on the respective bands which are then merged to form a cigarette filler stream, and includes rod-forming means for enclosing the cigarette filler stream in a continuous wrapper to form a continuous cigarette rod, and means 622 for forming or feeding onto at least one of the sub-streams, or between the sub-streams as or just before they merge, a layer of core-forming material which is narrower than each of the sub-streams and is centrally located in relation thereto, whereby the core-forming material is surrounded by tobacco in the finished cigarette rod. This invention also encompasses the feeding of additional dense-ending quantities of tobacco instead of a core-forming layer. The additional material may be fed by a third suction band (842, 844, Fig 6). <IMAGE>

Description

Cigarette Making Machine This invention is concerned with a number of improvementslmodifications with respect to the cigarette making machine concept described in our U.S. patent No. 5,199,446 in which a cigarette filler stream is formed by showering tobacco towards two converging bands to form two tobacco sub-streams which are merged to form a single cigarette filler stream.

Reference is also directed in this context to our U.S. patent No.

5,141,003 and to our British patent specification 2269975A.

One aspect of this invention is concerned with a method or machine for manufacturing cigarettes having a core of tobacco or other particulate material different from the tobacco which forms the remainder of the cigarette filter and which surrounds the core.

In a method of making cigarettes in accordance with this aspect of the invention, tobacco is showered onto two suction bands to form two tobacco sub-streams of similar width which are then merged to form a cigarette filler stream which is used to form a continuous cigarette rod, including the step of forming or feeding onto at least one of the sub-streams a continuous or substantially continuous layer of particulate material different from the tobacco of the sub-streams, or feeding such a layer between the sub-streams as or just before they merge, the said layer or layers being narrower than each of the sub-streams and being centrally placed in relation thereto so that each of the sub-streams extends laterally beyond the lateral edges of the layer or layers, and so that the layer or layers will form a core in the finished cigarette filler stream surrounded by tobacco.

Another aspect of this invention is concerned with a method or machine for manufacturing cigarettes with denser end portions.

Examples of cigarette making machines embodying various aspects of this invention are shown in the accompanying diagrammatic drawings in which: Figure 1 is a plan view of one machine used to manufacture cigarettes with denser end portions; Figure 2 shows a modification of the machine shown in Figure 1; Figure 3 is a diagrammatic plan view of a machine for forming core-centred cigarettes; Figure 4 is a section on the-line A-A n Figure 3; Figure 5 is a section on the line B-B in Figure 3; Figure 6 is a diagrammatic plan view of another machine; Figure 7 shows a modification on a larger scale of part of the machine shown in Figure 6; and Figure 8 is a diagrammatic plan view of another machine.

Figure 1 shows a machine comprising converging suction bands 510 and 512 onto which tobacco is showered substantially horizontally from a shower channel 514. Tobacco sub-streams (not shown) build up on the bands 510 and 512 and are combined or merged as the bands move along parallel paths starting from a merger zone 516. The merged cigarette filler stream thus formed is enclosed in a paper wrapper in what may be a virtually standard garniture.

Tobacco showered approximately along the middle of the channel 514 is used to form dense-ending mounds of tobacco 518 on a band 520. For this purpose, a channel is formed between a fixed wall 522 and a parallel run of the band 520, tobacco being drawn into that channel partly by the action of a supercharger louvre 524 formed in a bottom wall of the channel 514. Suction is applied through the band 520 to hold the dense end portions 518 on the band until they are ready to be released onto the band 510. The quantity of tobacco drawn into the channel to form dense ends may be controlled by controlling the level of suction applied to the louvre 524 and/or by controlling the level of suction applied through the band 520.

Rollers 526 and 528 rotate in the indicated directions so that tobacco which might otherwise be caught on the edges of the adjacent fixed walls 530 and 532 are instead directed as shown.

The band 520 is of woven nylon so as to be air-pervious along its entire length. However, a non-pervious carrier band inside the nylon band is formed with apertures at regular intervals which define the areas at which dense-ending tobacco is collected on the nylon band. The carrier band is tensioned by a pulley 534 and returns around a pulley 536, while the nylon band extends further and returns around a pulley 538. The nylon band may also include a separate tensioning arrangement and may be driven separately from the carrier band.

Figure 2 shows an alternative construction which differs in that dense-ending tobacco is showered directly onto a band 540 arranged to pass around pulleys 542 and 544. As in Figure 1, dense end portions of tobacco 546 form on the band 540 and are delivered onto the sub-stream carried by band 510 before the sub-streams carried by the bands 510 and 512 are combined or merged to form the complete cigarette filler stream. A roller like roller 526 or 528 in Figure 1 may be included at the junction of two fixed walls 548 and 550. The band 540 is inclined to the tobacco shower by an angle a which may be increased if so desired.

The band 540 may be of non-porous material which has perforated areas for picking up dense-ending portions of tobacco.

Alternatively, as mentioned with respect to Figure 1, there may be two bands, the inner band being non-porous but having apertures at regular intervals, while the outer band is possibly of woven nylon.

Figure 3 shows a machine which is used to manufacture core-centred cigarettes. As before, it has converging suction bands 610 and 612 onto which tobacco is showered, in this case through two separate channels 614 and 616 defined by parallel upper and lower walls and by side walls 61 4A,61 4B and 61 6A,61 6B respectively. This tobacco forms a wide shallow layer of tobacco on each of the bands 610 and 612. Figure 4 shows the layer of tobacco 618 which is formed on the band 612 and is held on the band by suction applied through the band from a suction chamber 620. A similar arrangement applies to the band 610.

The wide layers formed on the bands 610 and 612 may be trimmed by trimming devices 611 and 613 mounted in spaces formed by the walls 6148 and 616B and additional walls 614C and 616C.

Alternatively, the thicknesses of the wide tobacco layers may be controlled or evened out by other means, for example as described in British patent application No. 9422581.

Between the shower channels 614 and 616 there is a shower channel 622 through which additional particulate material (tobacco and/or other material) is showered towards both of the bands 610 and 612. In the regions where this additional particulate material arrives on the band 612, the shower channel is reduced in width by rails 624 and 626 (see Figure 5) having inner surfaces 624A and 626A which define the width of a layer 628 of the additional particulate material which forms along a central region of the tobacco layer 618. The same applies to the other half of the machine in the region of the band 610.

Thus each layer 618 of tobacco arrives at a merger point between pulleys 61 0A and 61 2A carrying on it a centrally positioned layer of the additional particulate material. The two layers of that material are brought together and combined to form a core in the finished cigarette filler stream surrounded by tobacco. Excess particulate material may be removed by a pin-carrying wheel 630 rotating about a horizontal axis and sheltered from showered particulate material by a V-shaped cover 631.

In moving from the pulleys 61 0A and 61 2A to further pulleys 61 OB and 612B (which have concave peripheral cross-sections), the bands become progressively concave in cross-section so as to wrap the side edge portions of the layers 618 around the sides of the core and to shape the cigarette filler stream towards a circular cross-section. After passing the pulleys 61 0B and 61 2B the bands become progressively flat again in cross-section as they approach further pulleys 610C and 612C, and they remain flat as they move from the latter pulleys to further pulleys 61 0D and 612D.

The cigarette filler stream thus formed may be carried into a conventional garniture in which it is wrapped in a continuous paper web to form a continuous cigarette rod which is then cut into discrete lengths.

Alternatively, the entire core layer may be formed on one of the bands 610 or 612.

As a further alternative, the additional particulate material may be showered onto a separate suction band lying between the converging bands 610 and 612 (for example, like the band 520 shown in Figure 1) to form a narrow layer of additional particulate material which is then laid onto one of the tobacco streams on the band 610 or 612 before the tobacco streams arrive at the merger zone 630. Another possibility is that the additional particulate material may be showered onto two converging bands situated above or below the bands 610 and 612 to form a stream which may be fed between the tobacco layers, in the region of the pulleys 61 0A,612A, by a suction wheel or through a guide tube.

The additional particulate material may comprise, for example, relatively long stands of low-quality tobacco or other material which will assist in preventing ends fall-out of tobacco from the finished cigarettes.

Alternatively, or in addition, it may comprise or include stems and other heavier pieces of tobacco winnowed out of the tobacco used to form the tobacco layers, or tobacco with any desired additional substance for modifying one or more characteristics of the finished cigarettes.

Figure 6 shows a machine which is similar in that tobacco is showered onto suction bands 810,812 through horizontal shoter channels 814,816. Tobacco layers thus formed on the bands max be trimmed by trimming devices 811,813 before being brought together while moving along guide members 838,840 for the two bands.

This example differs from Figure 3 principally in that the additional particulate material is showered through a horizontal channel 822 extending towards additional converging suction bands 842,84 to form two separate sub-streams of particulate material on the two bands which are merged as the bands move along parallel paths beyond a merger point 846. The complete core stream thus formed then passes through a nozzle 848 to enter the gap between the tobacco layers formed on the bands 810,812. As in the example of Figure 9, the flow of core material into that gap is assisted by an axial air flow induced by air drawn through the bands 810,812 from suction manifolds 834,836.

The construction of the machine shown in Figure 6 is preferably as shown in Figure 7. This figure shows tobacco layers 81 OA and 81 2A which have been formed on the bands 810,812 and between which the core stream is injected as the bands 810,812 proceed beyond guide pulleys 81 0B,81 2B.

The member 848 through which the core material passes before entering the gap between the tobacco layers is in the form of a tube of which the outer surface at both ends converge so as to end as a relatively sharp edge. The bands 842,844 carrving the merged stream of core material are constrained by suitably shaped guide members (not shown) so as to diverge at 842A,844A as they approach guide pulleys 842B,844B on opposite sides of the tubular member 848.

The centre bore in the member 848 has a square or rectangular cross-section.

Another possibility is that a layer of particulate core material may be formed on a suction band and then be fed (possibly after trimming) onto one of the tobacco sub-streams. Alternatively two sub-streams of core material may be formed by showering particulate material, for example, onto two diverging suction bands, the two core sub-streams being deposited respectively on t;ie tobacco sub-streams (preferably after these have been trimmed' before these are merged to form a complete core-centred cigarette flier stream.In comparison with Figure 6, the latter alternative would in effect involve the showering of core material through the channe 822 onto two short diverging bands, instead of onto converging bands 842,844, so that each core sub-stream can be deposited on its respective tobacco sub-stream before the merger point; the cross-section through each main band just before the merger point may thus be similar to Figure 5.

Figure 8 shows a machine which is similar to that shown in Figure 6, as indicated by the use of the same reference numerals. Additional reference numerals 814A, 814B, 822A, 822B, 81 6A and 81 6B identify the side walls of the shower channels 814,822 and 816.

Figure 8 differs in that, in place of the converging additional bands 842,844 for forming the core stream, there are diverging additional suction bands 850 and 852 which form sub-streams of particulate material showered through the channel 822. Each of the sub-streams is placed on the corresponding tobacco sub-stream carried by the suction band 810 or 812 as the case may be. Additional trimming devices 854 and 856 may be provided for trimming the core sub-streams; however, these trimming devices or the trimming devices 811,813 may be omitted.

A further difference in this example is that the suction bands 810,812 approach one another while moving along a gentle curve defined by fixed guides 858 and 860. These guides are perforated or porous so that air can be drawn through them from the suction manifolds 834,836 to hold the sub-streams on the bands 810,812 before they are brought together where the bands move along straight parallel guide members 8381 and 8401. In this example suction is not drawn through the bands in the region of the guide members 8381,8401 since there is not intended to be any significant axial air flow of air which could disturb the core sub-streams as they move around the guides 858,860.

Furthermore, in order to avoid or minimise any such axial air flow, there may be one or more openings in the top and/or bottom wall of the machine above or below (and centrally between) the fixed guides 858,850, so that air drawn through the bands 810,812 in the region of the guides 858,860 passes substantially normally through the suction bands.

It should be noted that the additional band 850 for core material is longer than the band 852, so that the core sub-streams will be of slightly different thickness. Alternatively, the bands 850,852 may be differently arranged so that identical core sub-streams are formed on them.

As already mentioned, the trimming devices 811,813 may be omitted. In that case, the side walls 822A and 822B would be omitted, and the bands 850,852 would be made longer and would be rearranged (moved apart) in order to receive all the particulate material showered through the channel 822.

Figure 9 shows a different form of machine for producing core-centred cigarettes. Tobacco is showered onto converging suction bands 710 and 712 through horizontal shower channels 714 and 716 to form identical layers of tobacco on the bands 710,712 as in the Figure 3 example. Also as before, the tobacco layers maybe trimmed by trimming devices 711 and 713 before the layers are brought together around a core of additional particulate material.

In this example a stream of core material is showered through a shower channel 722 formed by horizontal top and bottom walls and by converging side walls 722A and 722B. Thus particulate material showered through the channel 722 converges to form a core stream at the downstream ends of the walls 722A,722B, and this core stream enters a gap between the tobacco layers carried by the bands 710,712.

Tobacco arriving on the bands 710,712 is held on the bands by suction transmitted through the bands from suction manifolds 730 and 732. Suction continues to be applied to the bands from further suction manifolds 734,736 as the bands move along slightly converging paths and then along parallel paths extending along guide walls 738,740, these are perforated so that air can be drawn through them from the manifolds 734,736, as shown by the air flow arrows. The air drawn through the bands in this region induces an axial air flow which draws the additional particulate material through the channel 722 and into the gap between the tobacco layers formed on the bands 710,712.

The guide walls 738,740 may be concave in cross-section, or may become progressively concave, to fold the side edge portions of the tobacco layers around the core, as described with reference to Figure 3.

The core-centred cigarette filler stream thus formed may, as in the previous example, be carried into a conventional garniture by a further suction band (not shown) to enable the filler stream to be sealed in a continuous paper wrapper.

Claims

Claims:

1. A method of making cigarettes, in which tobacco is showered onto two suction bands to form two tobacco sub-streams of similar width which are then merged to form a cigarette filler stream which is used to form a continuous cigarette rod, including the step of forming or feeding onto at least one of the sub-streams a continuous or substantially continuous layer of particulate material different from the tobacco of the sub-streams, or feeding such a layer between the sub-streams as or just before they merge, the said layer or layers being narrower than each of the sub-streams and being centrally placed in relation thereto so that each of the sub-streams extends laterally beyond the lateral edges of the layer or layers, and so that the layer or layers will form a core in the finished cigarette filler stream surrounded by tobacco.

2. A method according to claim 1, including the step of folding the side portions of the tobacco sub-streams around the sides of the core-forming layer as the sub-streams and layer are conveyed together prior to being enclosed in a continuous wrapper to form a continuous cigarette rod.

3. A method according to claim 1 or claim 2, in which the layer or a portion thereof is formed by showering the particulate core material onto one of the tobacco sub-streams between guides confining the showered core material to form the layer substantially centrally along the sub-stream and with a narrower width.

4. A method according to claim 1 or claim 2, in which the or each layer is formed by showering core material onto one of more separate conveyors.

5. A method according to claim 1 or claim 2, in which the layer is formed by showering particulate core material through a channel comprising converging walls guiding the core material towards a gap between the tobacco sub-streams.

6. A method according to any one of claims 1,2 and 5, in which particulate material forming the core in the finished cigarette is drawn into a gap between the tobacco sub-streams at least partly by the action of an air flow induced by suction applied through the suction bands in a region where the sub-streams are conveyed along substantially parallel paths while being spaced apart to form the gap.

7. A cigarette making machine comprising means for showering tobacco onto two suction bands to form tobacco sub-streams of similar width on the respective bands which are then merged to form a cigarette filler stream, and including rod-forming means for enclosing the cigarette filler stream in a continuous wrapper to form a continuous cigarette rod, and means for forming or feeding onto at least one of the sub-streams, or between the sub-streams as or just before they merge, a layer of core-forming particulate material which is narrower than each of the sub-streams and is centrally located in relation thereto, whereby the core-forming material is surrounded by tobacco in the finished cigarette rod.

8. A machine according to claim 7, in which the means for forming the layer of core-forming particulate material comprises means for showering the particulate material.

9. A machine according to claim 8, in which the showered core material is arranged to form a layer directly on at least one of tobacco sub-streams.

10. A machine according to claim 8, in which the showered core material is arranged to form a layer on at least one additional suction conveyor.

11. A machine according to claim 10, in which the showered core material is arranged to form layers on two converging suction conveyors, which layers are merged before being fed into a gap between the tobacco sub-streams.

12. A machine according to claim 10, in which the showered core material is arranged to form layers on two diverging suction conveyors, each of which layers is fed onto one of the tobacco sub-streams.

13. A machine according to claim 8, in which the showered core material is arranged to pass between converging fixed walls so as to form a stream of particulate material which is arranged to be fed directly into a gap between the tobacco sub-streams.

14. A machine according to claim 13, in which the particulate material is arranged to be drawn into the gap between the tobacco sub-streams at least partly by the action of an air flow induced by suction applied through the suction bands in a region where the sub-streams are conveyed along substantially parallel paths while being spaced aparttoform the gap.

15. A method of making cigarettes, in which tobacco is showered onto two suction bands to form two tobacco sub-streams of similar width which are then merged to form a cigarette filler stream which is used to form a continuous cigarette rod, including the step of forming or feeding onto at least one of the sub-streams a continuous or intermittent layer of tobacco or other particulate material by showering the said particulate material onto an additional suction band and then transferring the layer of particulate material onto the tobacco sub-stream formed on one of the first-mentioned suction bands.

16. A method according to claim 15 in which the additional suction band is arranged to attract the particulate material to it only at positions corresponding to the end portions of the finished cigarettes.

17. A cigarette making machine comprising means for showering tobacco onto two suction bands to form tobacco sub-streams of similar width on the respective bands which are then merged to form a cigarette filler stream, and including rod-forming means for enclosing the cigarette filler stream in acontinuouswrappertoform acontinuous cigarette rod, and means for feeding onto at least one of the sub-streams a continuous or intermittent layer of tobacco or other particulate material by showering the said particulate material onto an additional suction band and then transferring the layer of particulate material onto the tobacco sub-stream formed on one of the first-mentioned suction bands.

18. A machine according to claim 17 in which the additional suction band is arranged to attract the particulate material to it only at positions corresponding to the end portions of the finished cigarettes.

19. A machine according to claim 18 in which the additional suction band comprises a first band which is uniformly air-pervious at various positions along its length, and a second band which runs along and adjacent to the first band in the region where showered particulate material is received, and is perforated at longitudinally spaced positions at which the particulate material is to be attracted.

20. A method of making cigarettes according to claim 1 or claim 15 and substantially in accordance with any one of the examples described with reference to the accompanying drawings.

21. A cigarette making machine according to claim 7 or claim 17 and substantially in accordance with any one of the examples described with reference to the accompanying drawings.