EP1512336B1 - Method and apparatus for manufacturing a filter rod - Google Patents

Description

The invention relates to a method for producing a filter strand of the tobacco-processing industry comprising at least one filter material. The invention further relates to a device for producing a filter strand of the tobacco processing industry comprising a conveying element can be applied to the filter material and a strand forming device for forming a filter strand of the filter material, wherein the conveying element extends into the strand forming device.

A corresponding method and a corresponding device are known from DE-OS-1 692 901. There is described a method of manufacturing tobacco smoke filters in which substantially continuous filament material is produced by spray spinning which is conveyed against a continuously moving collecting surface arranged at an angle to the spraying path, whereby an elongate strip of randomly arranged filament sections results and parts of the belt are laterally moved relative to each other to form an endless filter strand therefrom. After spinning, various additives can be added to the thread material by known methods. The thread material used can be cellulose acetate threads or filaments of polyethylene and polypropylene.

It is an object of the present invention to provide a generic method and a generic device can be made with or with the effective filter strands with high quality.

• Schmelzen wenigstens einer ersten Sorte Filtermaterial,
• Drücken der wenigstens einen ersten Sorte Filtermaterial durch wenigstens eine Düse,
• Aufbringen der wenigstens einen ersten Sorte Filtermaterial in Form von Fasern auf ein Förderelement, und
• Formen des Filterstrangs durch Fördern des Filtermaterials auf dem sich durch eine Formungsvorrichtung erstreckenden Förderelement durch eine Formungsvorrichtung.

This object is achieved by a method for producing a filter strand of the tobacco-processing industry comprising at least one filter material with the following process steps:

• Melting at least a first type of filter material,
• Pressing the at least one first type of filter material through at least one nozzle,
• Applying the at least one first type of filter material in the form of fibers to a conveying element, and
• Forming the filter strand by conveying the filter material on the conveying element extending through a forming device through a forming device.

Due to the pressing of the at least one first type of filter material through at least one nozzle, after the filter material has been melted or plasticized, that is, sufficiently softened, corresponding threads are produced which are thrown onto the conveying element. This creates a corresponding crimping of the squeezed out of the nozzle threads. Pressing out of the nozzle can also be a squirting out. The threads are on the way to the conveying element and preferably still sticky on the conveying element or still plastified such that at points of contact or crossing points of the corresponding threads adhere or stick to each other. This results in a very efficient filter strand with very good filter properties in high quality. In a particularly preferred embodiment of the method according to the invention, the at least one first type of filter material is pressed by means of compressed air through the at least one nozzle. As a result, the curling effect of the resulting filter material threads can be increased. In addition, an efficient filter strand production is given by the fact that the filter filaments from the at least one first type filter material are applied to a conveying element, which transports the filter material shortly thereafter by a shaping device, so that the process parameters can be adjusted without problems such that during the molding of the filter strand the filter material is still plasticized. As a result, little or no additional energy in the shaping is necessary.

The filter properties are then markedly improved if at least one second type of filter material in the form of pellets, granules and / or powder is fed to the at least one first type of filter material following the extrusion out of the at least one nozzle. The second type of filter material may be, for example, activated carbon granules or powders or pellets. However, flavorings or other additives may also be used.

If the at least one second type of filter material is supplied at a time to the at least one first type of filter material, at which the first type filter material allows adhesion of the second type filter material, a secure combination of the various filter materials is possible. In this case, it is particularly preferred to supply the second type of filter material at a time of the first type filter material to which the first type filter material has not yet struck the conveying element is. As a result, a very high mixing of the filter materials is achieved, whereby the quality, in particular the homogeneity, of the filter strand is improved.

A particularly effective production of a filter strand with wrapping material strips is possible if the at least one first type of filter material is applied to a wrapping material strip applied to the conveying element. The wrapping material strip is preferably porous so that air can pass therethrough. Also, the conveying element is preferably permeable to air, so that through the conveying element and possibly the wrapping material strip suction air acts on the filter materials to ensure a secure bond of these.

If initially a layer of the at least one first type of filter material is applied, a wrapping material strip can be avoided or a filter strand or a filter can be produced which has only a filter material or a type of filter material in the outermost layer.

Subsequently, when further filter material is applied to the layer, such as a mixture of a first grade and a second grade of filter material, the filter characteristics can be improved. This applies even more if the further filter material at least partially comprises the second type of filter material. For example, it is possible to use a very high proportion of pellets or granules and / or powder. It can be achieved granules of more than 90 wt.%.

If the applied layer has a width sufficient to cover the further filter material, the applied layer can replace a strip of wrapping material. Preferably, in the forming device, the applied layer is wound around the further filter material.

Alternatively, if subsequently a layer of the at least one first type of filter material is applied, whereby the further filter material is substantially completely enveloped by the layers, another possibility of enveloping the further filter material by layers of the at least one first type of filter material is possible. Preferably, the layers and optionally the layers are joined together with the further filter material in the molding device. This is preferably done by adding heat and corresponding pressure, which already affects the filter material by the shaping.

Preferably, the at least one second type of filter material is supplied to the at least one first type of filter material on the way from the at least one nozzle to the conveying element. In an alternative to this, the at least one second sort of filter material is supplied to the at least one first type of filter material after the first type of filter material has been applied to the conveyor element.

If, in the conveying direction of the conveying element, a plurality of filter material of the first and / or second types is applied in succession, a type of filter material sandwich or a filter material multiple structure can be produced.

Among the first type of filter material are, in particular, filter materials such as cellulose acetate, polyethylene, polypropylene, nylon, polybutadiene (PBT), polycarbonate (PC), hot glue, which is known per se in the tobacco processing industry or the packaging of products of the tobacco processing industry, and also understood biodegradable polymers of mixtures with starch.

The object is further achieved by a device for producing a filter strand of the tobacco-processing industry comprising a conveying element, can be applied to the filter material and a strand forming device for forming a filter strand from the filter material, wherein the conveying element extends into the strand forming device, and wherein at least one nozzle is provided, can be brought by the liquefied or plasticized filter material at least a first grade on the conveying element.

The device according to the invention makes it possible to produce filter strands effectively and with very good filter properties and high quality. Preferably, a wrapping material strip is arranged between the conveying element and the filter material. If in each case a pair of nozzles is provided, which are partially directed against each other, there is an increased curl and entanglement of emerging from the nozzle threads of the filter material. Preferably, a plurality of nozzles are provided behind one another in the conveying direction of the conveying element, whereby a very good mixing or entanglement of the filaments of filter material is formed. If at least one supply device is provided for at least one second type of filter material, the filter properties can be significantly improved. Preferably, at least one feeding device is configured to convey the filter material of the second kind onto a jet of filter material of the at least one first sort emerging from the nozzles. As a result, the mixing of the filter materials of the first and the second variety is increased. Preferably, the strand forming device is at least partially heated and / or cooled.

A method of manufacturing a cigarette filter comprising a method of manufacturing a filter rod of the tobacco processing industry described above provides for the cigarette filter to be cut to length from the produced filter string.

Fig. 1

eine schematische Vorderansicht eines Teils einer erfindungsgemäßen Vorrichtung,

Fig. 2

eine schematische Seitenansicht entlang des Schnitts A-A der Fig.1,

Fig. 3

eine vergrößerte schematische Darstellung eines Ausschnitts aus Fig. 2,

Fig. 4

eine schematische Darstellung einer weiteren Ausführungsform eines Teils einer erfindungsgemäßen Vorrichtung in Vorderansicht,

Fig. 5

eine schematische Schnittdarstellung entlang des Schnitts A-A aus Fig. 4,

Fig. 6

eine vergrößerte schematische Darstellung eines Ausschnitts aus Fig. 5,

Fig. 7 a)

eine schematische Darstellung eines Schnitts durch die Strangaufbauzone zu Beginn des Strangaufbaus,

Fig. 7 b)

eine entsprechende schematische Schnittdarstellung gemäß 7 a) wobei der Schnitt stromabwärts der Strangherstellung dargestellt ist,

Fig. 7 c)

eine Schnittdarstellung gemäß Fig. 7 b) weiter stromabwärts,

Fig. 7 d)

eine Schnittdarstellung gemäß Fig. 7 c) weiter stromabwärts,

Fig. 8 a)

eine schematische Darstellung eines Schnitts entsprechend der Fig. 7a) in einer anderen Ausführungsform,

Fig. 8 b)

eine schematische Darstellung eines Schnitts entsprechend Fig. 7 b) in einer anderen Ausführungsform,

Fig. 8 c)

eine schematische Schnittdarstellung entsprechend Fig. 7 c) in einer anderen Ausführungsform

Fig. 8 d)

eine schematische Schnittdarstellung entsprechend Fig. 7 d) in einer anderen Ausführungsform

Fig. 9

eine schematische dreidimensionale Darstellung einer erfindungsgemäßen Strangmaschine,

Fig. 10

einen Ausschnitt aus der erfindungsgemäßen Strangmaschine aus Fig. 9 in vergrößerter Darstellung,

Fig. 11

eine schematische Seitenansicht der Strangmaschine aus Fig. 9,

Fig. 12

eine schematische Darstellung eines Ausschnitts aus Fig. 11 in Vergrößerung,

Fig. 13

eine schematische dreidimensionale Darstellung einer weiteren Ausführungsform einer erfindungsgemäßen Strangmaschine und

Fig. 14

einen Ausschnitt aus der Fig. 13 in vergrößerter Darstellung.

In the following the invention without further restriction of the general inventive concept will be described in more detail by means of exemplary embodiments. With respect to all details of the invention not explained in detail, reference is expressly made to the drawings. Show it:

Fig. 1

a schematic front view of a part of a device according to the invention,

Fig. 2

a schematic side view along the section AA of Figure 1,

Fig. 3

an enlarged schematic representation of a detail of Fig. 2,

Fig. 4

a schematic representation of another embodiment of a part of a device according to the invention in front view,

Fig. 5

3 is a schematic sectional view along the section AA of FIG. 4,

Fig. 6

an enlarged schematic representation of a detail of Fig. 5,

Fig. 7 a)

a schematic representation of a section through the strand construction zone at the beginning of the strand structure,

Fig. 7b)

a corresponding schematic sectional view according to 7 a) wherein the section is shown downstream of strand production,

Fig. 7c)

a sectional view of FIG. 7 b) further downstream,

Fig. 7d)

a sectional view of FIG. 7 c) further downstream,

Fig. 8 a)

a schematic representation of a section corresponding to the Fig. 7a) in another embodiment,

Fig. 8b)

3 is a schematic representation of a section corresponding to FIG. 7 b) in another embodiment,

Fig. 8c)

a schematic sectional view corresponding to FIG. 7 c) in another embodiment

Fig. 8d)

a schematic sectional view corresponding to FIG. 7 d) in another embodiment

Fig. 9

a schematic three-dimensional representation of a strand machine according to the invention,

Fig. 10

a detail of the strand machine according to the invention from FIG. 9 in an enlarged view,

Fig. 11

1 is a schematic side view of the stranding machine of FIG. 9, FIG.

Fig. 12

1 is a schematic representation of a section of FIG. 11 in enlargement,

Fig. 13

a schematic three-dimensional representation of another embodiment of a strand machine according to the invention and

Fig. 14

a section of FIG. 13 in an enlarged view.

Fig. 1 shows a schematic representation of part of a strand machine according to the invention or apparatus for producing a filter strand of the tobacco processing industry in front view. From appropriate storage containers, such as a Hot melt stock 11, which can also be referred to as hot melt adhesive supply 11, is discharged via a nozzle 10 hot glue under pressure and fed to a shell material 17 and a format strip 19. Instead of a hot melt adhesive 14 known in the tobacco processing industry, other materials such as polypropylene, polyethylene, cellulose acetate, propylene carbonate or bisphenol A carbonic acid based polycarbonates may also be used , Nylon and biodegradable polymers of blends with starch. After exiting the nozzle 10, these materials, in the embodiment of Fig. 1 hot glue 14 or hot melt adhesive or as another example, biodegradable polymers of mixture with starch or the aforementioned materials in the form of threads present correspondingly by sufficient pressure curled on the wrapping material 17 or the format tape 19 hang up.

In order to improve the filter properties, a granulate 15 is introduced from the granulate supply 13 via feed tubes 12 directly into the hot glue fibers 14 or hot glue threads 14. This results in a very good mixing of the two filter materials hot glue 14 and granules 15. The corresponding fibers or threads that emerge from the nozzles 10 are on the way to the shell material 17 and the format tape 19 still correspondingly adhesive or adhesive, so that the other filter materials, namely, for example, the granules 15 and other threads stick together or adhere to each other. This creates a secure bond of the corresponding filter materials. There are provided in the embodiment of FIG. 1, three nozzles 10 and two feed tubes 12, so that a sufficient amount of filter material in a short time on the Hüllmaterialstreifen 17 and the format tape 19 is applied. As a result, a high production speed can be achieved become. The format belt 19 moves in the conveying direction 18 in the direction of a forming carrier, which is not shown in Fig. 1.

Fig. 2 shows a sectional view in the direction of the section A-A in a schematic representation. In this sectional view, the shape of the wrapping material 17 and the format strip 19 is shown in more detail. When using a wrapping material 17, this would rest on the format tape 19 in a conventional manner. An enlarged view of the mixture 16 is shown in Fig. 3, in which granules 15 and hot glue threads 14 can be seen, which are crimped.

FIGS. 4 to 6 show another embodiment of a part of a stranding machine according to the invention. In this embodiment, on the one hand, the format tape 19 is executed plan and that as long as the corresponding filter material is applied. Only downstream in the conveying direction, the format strip is then shaped in accordance with a format device to produce a filter strand. In the exemplary embodiment of FIGS. 4 to 6, hot melt threads 14 and granules 15 are applied alternately, the outer layers consisting of corresponding threads. This creates a kind of sandwich structure. The first layer of hot glue threads is applied over a width B. The width B is sufficient to be wrapped around the entire further applied filter material. The width B then corresponds to at least 2 π r, with r as the radius of the filter strand to be produced.

A corresponding application of filter material, which occurs successively in a certain manner, is shown in FIGS. 7 a) to 7 d). First, a layer 21 in the form of a nonwoven fabric from corresponding hot glue fibers 14 is applied to the format strip 19. During the order of this layer is over the Suction air through this entire range of the format strip 19 passed therethrough, so that the hot glue threads 14, which form the fibrous web 21 are held on the format strip 19. After production of the nonwoven fabric 21, a mixture of hot glue threads 14 and granules 15 is applied in or on the nonwoven fabric 21. At this point, only the middle part of the format belt 19 is acted upon by suction, so that the corresponding mixture 16 accumulates only in a partial area. Subsequently, the filter material is moved by means of the format strip 19 in a forming apparatus in which the nonwoven fabric 21 and the format tape 19 is wound around the mixture 16. Finally, after the nonwoven fabric 21 has been completely wound around the mixture 16, it is joined at the seam 23 by heating and accordingly the nonwoven fabric 21 is closed.

Another embodiment is shown in FIGS. 8 a) to 8 d). In this case, the wrapping of the mixture 16 with two fiber webs 21 and 21 ', wherein initially a nonwoven fabric 21 is generated, then the mixture 16 is placed in the nonwoven fabric 21 and then a kind of cover in the form of a nonwoven fabric 21' applied to the mixture becomes. In the forming device, which is not shown, then the two seams 23 are connected to each other by the action of heat.

The fiber strand which is produced in these exemplary embodiments (as shown in FIGS. 6 to 8) can be distinguished by particularly high proportions of granules. Furthermore, the filter elements which are cut to length from the fiber strand produced, according to the embodiments of FIGS. 6 to 8 without a separate wrapping material. The granules are held by fibers accordingly.

Through the nozzles 10 and spinnerets of a spinneret head 27 (FIG. 9 or 13), a thread or a fiber is produced accordingly. A spinneret head 27, which is preferably used, carries the name Summit System from Nordson.

From the Granulatzuführrohren 12 granules 15 is blown along with fibers on a format strip 19, which may be formed as a suction belt, so that connect the granules and the still slightly sticky filaments of the thermoplastic. In this case, the format strip 19 moves in the direction of a strand forming device 22, 22 '(FIG. 9 or 13). In the strand forming apparatus, the strand is first heated and then cooled to plastically define the strand shape. In this way, a wrapping paper or a shell material 17 can be omitted. Optionally, after a granulate / fiber addition, a pure fiber layer can be applied again in order to envelop the rod completely with a fiber layer.

The rod formation, which is indicated schematically in FIGS. 7 d) and 8 d), is preferably effected by means of heating and subsequent cooling. Corresponding materials are as already shown in part all possible resins and polymers such as PP, PE, PBT, nylon, PC, CA, hot melt and biodegradable polymers from mixtures with starch. With regard to the corresponding materials, reference is made in full to EP 0 861 036 B1. All materials mentioned there should be included in full in the disclosure of this patent application. The mixture 16 preferably comprises between 80 and 95 wt.% (By weight) of activated carbon granules or powders and 5 to 20 wt.% Of a fiber of one or more grades of a thermoplastic (resin or polymer). The pellets or granules or powder are in a size of preferably 50 .mu.m to 4 mm ago. The fibers exiting the nozzles 10 may be finite or endless. It is also possible to produce pure fiber filters from the materials mentioned. These may consist of a variety of fibers or of different types of fibers.

FIG. 9 shows a schematic three-dimensional representation of a stranding machine 24 according to the invention. Hot melt glue 14 accordingly emerges from spinneret head 27, which comprises a plurality of nozzles, as shown for example in FIGS. 11 and 12, wherein a plurality of nozzles can also be arranged one behind the other in conveying direction 18 heated and conveyed through the respective nozzles in the hopper 26 and applied to a format strip 19 or a shell material 17 which is arranged on a format strip 19, wherein the format strip 19 is guided in a guide 25 in the lower region of the hopper 26 (see. Fig. 12). In the central region of the spinneret head 27 in the conveying direction, two Granulatzuführungen 28 are provided which terminate in feed tubes 12, which is supplied according to granules or pellets or powder on the format tape 19 given hot melt fibers. Subsequent to the feeding of filter material, a format follows 22 or 22 ', where first in a heating part 22 of the filter strand is formed to then cure in a cooling part of the format 22' the filter strand.

10 shows an enlarged view of a part of FIG. 9.

Fig. 11 shows a side view of Fig. 9 in a schematic representation, wherein the nozzles 10 are more clearly visible and also the strand building area. These can be seen most clearly in Fig. 12, which is an enlarged view of FIG. 11. In Fig. 12 and the format cover 29 is shown in more detail with a corresponding handle 30. The format 22 through which the corresponding Filter strand, which is not shown, is passed, is also shown in Fig. 12.

13 shows another embodiment of a stranding machine 24 according to the invention, wherein a plurality of granule feeds 28 are provided in this exemplary embodiment, so that a better thorough mixing of the granulate with the corresponding hot glue fibers or fibers made of another thermoplastic material is possible. In this exemplary embodiment (FIGS. 13 and 14), it is preferable to use a wrapping material or wrapping material 17, which is indicated by corresponding bobbins 31. In this embodiment of FIG. 13, the format with respect to the heating part 22 and the cooling part 22 'is formed separately.

Fig. 14 is an enlarged view of a portion of Fig. 13 for better illustration.

The main advantages of the method according to the invention and the device according to the invention lie in an adhesive-free connection of fibers and granules or of fibers per se. There is a very large amount of granules in relation to the fibers possible. Furthermore, the diameters of the fibers or filaments produced can be varied by simply exchanging the corresponding nozzles 10 or spinnerets on the spinneret head 27. It is possible to blend polymers accordingly to achieve improved fiber properties. Furthermore, the storage is simplified because fibers can be stored in the form of granules and not in the form of bales, so that less volume is needed in storage.

Preferably, the temperatures and the delivery rates adjusted so that at the point of the blades, which are provided to cut or cut off the filter strand into filter rods, the fiber strand has already sufficiently cooled. Furthermore, high strand speeds are possible. Other materials may also be added to the filter strand in a simple manner such as flavors and fillers, etc. Furthermore, in a particularly preferred embodiment, no separate wrapping material is necessary.

LIST OF REFERENCE NUMBERS

10

jet

11

hot glue

12

feed

13

granules stock

14

hot glue

15

granules

16

mixture

17

shell material

18

conveying direction

19

format tape

20

Filter material sandwich

21, 21 '

non-woven fabric

22

Format, heating part

22 '

Format, refrigerated part

23

seam

24

rod machine

25

guide

26

funnel

27

Spinning nozzle head

28

granulate feed

29

format lid

30

Handle

31

reel

B

width

Claims (22)

1. Method for producing a filter rod of the tobacco-processing industry, comprising at least one filter material (14, 15), with the following methods steps:

   - melting at least one first sort of filter material (14),

   - pressing the at least one first sort of filter material (14) through at least one nozzle (10),

   - applying the at least one first sort of filter material (14) in the form of fibres to a conveying element (19), and

   - shaping the filter rod by conveying the filter material (14, 15) on the conveying element (19) extending through a shaping device (22, 22'), through the shaping device (22, 22').
2. Method according to claim 1, characterised in that at least one second sort of filter material (15) is supplied in the form of pellets, granules and/or powder to the at least one first sort of filter material (14) following the pressing-out process from the at least one nozzle (10).
3. Method according to claim 2, characterised in that the at least one second sort of filter material (15) is supplied to the at least one first sort of filter material (14) at an instant at which the first sort of filter material (14) allows the second sort of filter material (15) to adhere.
4. Method according to any one of more of claims 1 to 3, characterised in that the at least one first sort of filter material (14) is applied to a strip of covering material (17) provided on the conveying element (19).
5. Method according to any one or more of claims 1 to 4, characterised in that first of all a layer (21) of the at least one first sort of filter material (14) is applied.
6. Method according to clam 5, characterised in that further filter material (14, 15) is subsequently applied to the layer (21).
7. Method according to claim 6, characterised in that the further filter material (14, 15) at least partially encompasses the second sort of filter material (15).
8. Method according to any one or more of claims 5 to 7, characterised in that the applied layer (21) has a width (B) which is sufficient to envelop the further filter material (14, 15).
9. Method according to claim 8, characterised in that the applied layer (21) is wound around the further filter material (14, 15) in the shaping device.
10. Method according to any one or more of claims 5 to 7, characterised in that a layer (21') of the at least one first sort of filter material (14) is subsequently applied, so the further filter material (14, 15) is substantially completely enveloped by the layers (21, 21').
11. Method according to claim 10, characterised in that the layers (21, 21') are joined together in the shaping device (22, 22').
12. Method according to any one or more of claims 2 to 11, characterised in that the at least one second sort of filter material (15) of the at least one first sort of filter material (14) is supplied to the conveying element (19) en route from the at least one nozzle (10).
13. Method according to any one or more of claims 2 to 12, characterised in that the at least one second sort of filter material (15) is supplied to the at least one first sort of filter material (14) once the first sort of filter material (14) has been applied to the conveying element (19).
14. Method according to claim 13, characterised in that filter material (14, 15) of the first and/or second sort(s) is successively and repeatedly applied in the conveying direction (18) of the conveying element (19).
15. Device for producing a filter rod of the tobacco-processing industry, comprising a conveying element (19) onto which filter material (14, 15) may be applied and a rod shaping device (22, 22') for forming a filter rod from the filter material, wherein the conveying element (19) extends into the rod shaping device (22, 22'), characterised in that at least one nozzle (10) is provided through which liquefied or plasticised filter material (14) of at least one first sort can be brought onto the conveying element (19).
16. Device according to claim 15, characterised in that a strip of covering material (17) is arranged between conveying element (19) and filter material (14, 15).
17. Device according to claim 15 and/or 16, characterised in that one respective pair of nozzles (10) is provided which are partially directed toward each other.
18. Device according to any one of more of claims 15 to 17, characterised in that a plurality of successive nozzles (10) is provided in the conveying direction (18) of the conveying element (19).
19. Device according to any one or more of claims 15 to 18, characterised in that at least one supplying device (12, 18) is provided for at least one second sort of filter material (15).
20. Device according to claim 19, characterised in that the at least one supplying device (12, 28) is configured to convey the filter material (15) of the second sort to a filter material (14) of the at least one first sort that issues from the nozzles (10).
21. Device according to any one of more of claims 15 to 20, characterised in that the rod shaping device (22, 22') can be at least partially heated and/or cooled.
22. Method for producing a cigarette filter comprising a method according to any one or more of claims 1 to 14, characterised in that the cigarette filter is cut into sections from the filter rod.

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