EP3031336A1 - Suction belt - Google Patents

Abstract

A suction belt (1) for transporting tobacco and / or filter material in the manufacture of cigarettes comprises a flat band-shaped band material (7) and a plurality of openings (11) distributed over the surface of band material (7). At least 75% of all openings (11) have a clear width of 0.3 mm or less.

Description

The invention relates to a suction belt for transporting tobacco and / or Fil-termaterial in the manufacture of cigarettes, with a flat, formed into a ring band material and with a plurality of distributed over the surface of the strip material openings.

A generic suction belt is out of DE 199 09 031 A1 known. The suction belt has a fabric of warp threads and weft threads, between which there are pores or openings, so that an air permeability of the fabric results, which allows suction of the tobacco or the filter material by means of vacuum. For better conveying of the tobacco or the filter material, one side of the band is smooth and the other side is made extremely rough, which in this case is achieved by a certain weave in which the weft threads are raised. The rough side should also allow better engagement with a drive wheel or the like to reliably drive the suction belt can.

In the DE 10 2011 006 803 B4 Another generic suction belt is described, the ends of which are connected in a connecting region by means of laser welding to form an endless suction belt. The suction belt also has a fabric with warp threads and weft threads, between which there are openings for sucking the tobacco or the filter material.

Similar suction belts, which likewise comprise fabrics of warp threads and weft threads and openings located between the warp threads and the weft threads, are also known from US Pat DE 10 2012 204 970 A1 , of the DE 10 2012 211 069 B4 or the DE 10 2012 223 074 A1 known.

A problem with most suction belts is often the fact that relatively many tobacco fibers to be transported are sucked through the suction belt and thus do not arrive at the point at which they are to be transported. In the case of fine dusts, this is a lesser problem since these are usually not desirable in cigarettes anyway. However, if it is larger fibers, it may well result in a major loss of up to 10% of the tobacco material used, which can lead to corresponding financial losses. Although it is in principle possible to reuse the tobacco fibers sucked through the suction belt, this also represents an expense which leads to undesirable costs.

It is therefore an object of the present invention to provide a suction belt for transporting tobacco and / or filter material in the manufacture of cigarettes, which allows a simple way to reduce or limit the amount of tobacco or filter material sucked through the suction belt.

According to the invention, this object is achieved by the features mentioned in claim 1.

As a result of the clear width of 0.3 mm or less according to the invention, which has at least 75% of all openings distributed over the surface of the strip material, the vast majority of tobacco fibers contained in the tobacco are prevented from being sucked through the suction band. This leads to a much lower loss of tobacco or filter material than in known suction belts, so that considerable costs can be saved.

The openings of the suction belt according to the invention are thus designed so that tobacco fibers are safely transported from a certain size and thus ultimately get into the cigarette, whereas very short tobacco fibers and particulate matter are sucked through the suction belt and can not get into the cigarette, which is the quality improved considerably.

The solution according to the invention can be implemented in various ways, but always with very low costs, in particular in comparison to solutions in which expensive devices or the like are used for the reuse of tobacco components sucked through the suction belt.

Depending on the desired filter level, d. H. the maximum amount of loss of tobacco and / or filter material can be provided in a very advantageous embodiment of the invention that at least 75% of all openings a clear width of 0.25 mm or less, preferably 0.22 mm or less, more preferably 0.2 mm or less, more preferably 0.17 mm or less, still more preferably 0.15 mm or less.

Another way to suck as little tobacco fibers through the suction belt, may consist in that at least 80%, preferably at least 85%, more preferably at least 90%, of all openings have a clear width of 0.3 mm or less.

An embodiment of the suction belt to be produced with very little effort and process reliability results when the belt material comprises a fabric with warp threads and weft threads, wherein the openings are located between the warp threads and the weft threads.

If, in a further embodiment of the invention, the two opposing surfaces of the strip material are substantially symmetrical to each other, wherein the fabric is bound with a plain weave and / or a twill weave, so there is an easy way to adjust the above-described size of the openings in the surface of the suction belt. In particular, when using a plain weave a very high air permeability is given due to the large number of binding points, whereby a reliable suction of the tobacco or the filter material is achieved.

In the case of using a fabric for forming the suction belt, it may be advantageous to achieve the above-described size of the openings when the warp threads and / or the weft threads have a thickness of about 0.25 mm or less.

Alternatively to the use of a fabric for the strip material may also be provided that the strip material comprises a knitted fabric, knitted fabric, scrim or a combination thereof. This may result in cost benefits.

Another alternative to using a fabric for the strip material may be that the strip material has a flat plastic film in which the openings are located. Such a strip material can be produced in different ways and the openings are introduced, for example by perforation.

In a further very advantageous embodiment of the invention can be provided that the two lateral edges of the suction belt are made substantially straight. Such a straight design of the two lateral edges of the suction belt prevents tobacco fibers and / or filter material from being sucked past the side of the suction belt, which also leads to a reduction in the loss of tobacco fibers or filter material. It is to be regarded as particularly advantageous if the two lateral edges of the strip material are designed straight so that they do not have recesses with a clear width of more than 0.3 mm.

In a further advantageous embodiment of the invention can be provided that the suction belt has two ends, which are connected in a connecting region by means of laser welding to form an endless suction belt. By connecting the ends of the suction belt by means of laser welding results in a very strong and durable connection of the suction belt. As a result, the suction belt can be clamped with higher clamping forces and the roughness, which is no longer present due to the smooth design of the two surfaces and has hitherto been used to drive the suction belt, can be compensated for.

A method for producing a suction belt is specified in claim 15. With such a method, the described straightening of the two lateral edges of the strip material can be carried out in a simple manner.

Further advantageous embodiments and modifications of the invention will become apparent from the remaining dependent claims. Embodiments of the invention are shown in principle with reference to the drawings.

Fig. 1

eine sehr schematische Darstellung eines erfindungsgemäßen Saugbands bei seinem Einsatz zum Transport von Tabak und/oder Filtermaterial;

Fig. 2

eine schematische Darstellung eines Schnitts durch einen Saugkanal, in dem das erfindungsgemäße Saugband bei seinem Einsatz angeordnet ist;

Fig. 3

eine sehr schematische Draufsicht auf eine erste Ausführungsform eines erfindungsgemäßen Saugbands; und

Fig. 4

eine sehr schematische Draufsicht auf eine zweite Ausführungsform eines erfindungsgemäßen Saugbands.

It shows:

Fig. 1

a very schematic representation of a suction belt according to the invention in its use for the transport of tobacco and / or filter material;

Fig. 2

a schematic representation of a section through a suction channel in which the suction belt according to the invention is arranged in its use;

Fig. 3

a very schematic plan view of a first embodiment of a suction belt according to the invention; and

Fig. 4

a very schematic plan view of a second embodiment of a suction belt according to the invention.

Fig. 1 shows in a very schematic representation of a suction belt 1, which serves for transporting not shown in the figures tobacco and / or filter material in the manufacture of cigarettes. The suction belt 1 can be used for example in a conventional manner in a machine for the production of cigarettes. In the present case, the formed into a ring suction belt 1 runs around two rollers 2, of which at least one is driven. The rollers 2 may for example be designed as gears to achieve a better connection with the suction belt 1 for driving the same. Of course, other embodiments of the rollers 2 are possible. Furthermore, it can be provided that the suction belt 1 rotates by more than the two rollers 2. However, since such arrangements are known per se, they are not illustrated in order to simplify the illustration.

The endless suction belt 1 is formed adjacent to a vacuum chamber 3, which serves to suck the tobacco or the filter material to the suction belt 1 with the prevailing in the same vacuum or negative pressure. Since this procedure is also known per se, it is likewise not described here in detail.

In Fig. 2 a suction channel 4 is shown, through which the suction belt 1 extends. The suction channel 4 is bounded on both sides by respective side walls 5, in which guide strips 6 are used, on which the suction belt 1 ideally abuts. Above the suction belt 1 is already in Fig. 1 represented vacuum chamber 3. The representation of Fig. 2 is to be regarded as very schematic, since it is intended to indicate only the purpose of the suction belt 1 for transporting tobacco and / or filter material.

Fig. 3 shows a first embodiment of the suction belt 1. The suction belt 1 has a flat, in a manner not shown in the Fig. 1 shown ring shaped strip material 7, which is connected at its ends in a connecting region, not shown, for example by means of laser welding to the endless strip material 7. The laser welding of the strip material 7 to obtain the endless suction belt 1, for example, in DE 10 2012 223 074 A1 described in detail and is therefore not further detailed herein. Of course, the two ends of the strip material 7 may also be joined by ultrasonic welding or other suitable method to form the endless suction belt 1. The strip material 7 used for the suction belt 1 may have a thickness of, for example, 0.5 to 2.5 mm.

The strip material 7 has in the embodiment of Fig. 3 a fabric 8 with warp threads 9 and weft threads 10 on. Between the warp threads 9 and the weft threads 10 are openings 11, which may also be referred to as pores, holes or recesses. The openings 11 in the fabric 8 or in principle in the band material 7, which forms the suction belt 1, serve to let the vacuum applied in the vacuum chamber 3 or the negative pressure through the suction belt 1 act through and thus the tobacco or the Aspirate filter material to the suction belt 1. For this purpose, a certain air permeability of the strip material 7 is necessary, which results through the openings 11. On the other hand, it may happen that in particular tobacco fibers are sucked through the openings 11 into the vacuum chamber 3. These tobacco fibers are then not transported to the desired location and are initially lost. To prevent this, it is provided in the suction belt 1 that at least 75% of all openings 11 a in Fig. 3 with "x" have a clear width of 0.3 mm or less. The proportion of openings 11, which has a clear width of more than 0.3 mm, may result, for example, due to corresponding manufacturing tolerances. By the term "clear width" is the largest width or length of the respective opening eleventh meant. In the present case, in which the openings 11 are made substantially rectangular, this is a diagonal within this rectangle.

In order to adapt the filtering effect of the suction belt 1 to the respective application, it can also be provided that at least 75% of all openings 11 have a clear width of 0.25 mm or less, preferably 0.22 mm or less, more preferably 0.2 mm or less, more preferably 0.17 mm or less, more preferably 0.15 mm or less. Furthermore, at least 80%, preferably at least 85%, more preferably at least 90%, of all openings 11 may have a clear width of 0.3 mm or less. These two restrictions or extensions can be linked together as desired. By a combination of these two restrictions, it is thus possible, for example, that at least 90% of all openings 11 have a clear width of 0.15 mm or less.

The described clear width of the openings 11 may in the embodiment of Fig. 3 be achieved by a corresponding type of binding of the fabric 8. For example, the fabric 8, as in FIG Fig. 3 shown to be bound with a plain weave. Furthermore, a twill weave or a combination of two weave types for the fabric 8 is also conceivable. In the case of using a twill weave, it is preferable to use a 2/1 twill weave, that is to say a weave with two warp threads 9 and a weft thread 10. By using suitable warp threads 9 and weft threads 10, in conjunction with a suitable weave, the inside width of the openings 11 can be placed in the desired range described above. Thus, the density of the warp threads 9 and / or the weft threads 10 is adjusted so that the desired clear width of the openings 11 is achieved. For example, the warp threads 9 and / or the weft threads 10 may have a thickness of about 0.25 mm or less. While filaments having a thickness of approximately 0.25 mm are frequently used for the warp threads 9, the weft threads 10 may have a thickness of 0.18 to 0.22 mm, for example.

The fabric 8 is further bound so that the two opposite surfaces of the fabric 8 and thus of the strip material 7 formed thereby are made substantially symmetrical to one another. In the present case, the two opposite surfaces of the fabric 8 and the strip material 7 are made as smooth as possible, which represents a departure from the suction belts used so far, which usually had a comparatively smooth and a much rougher side.

Preferably, the warp threads 9 and the weft threads 10 are formed as monofilament threads and consist of PEEK or polyamide. Optionally, other materials can be used.

In the embodiment of the suction belt 1 of Fig. 4 the same also has the band material 7, which is formed in this embodiment, however, by a flat plastic film 12 in which the openings 11 are located. For the maximum size of the openings 11 and the percentage minimum proportion of the openings 11 having this size, this applies with reference to Fig. 3 Been said. The plastic film 12 can be produced in a manner known per se and therefore not described here in detail, wherein the openings 11 can be introduced, for example, by perforation by means of needling, by means of laser radiation or the like. Of course, it is also possible to introduce the openings 11 already in the production process of the plastic film 12, for example by the plastic film 12 is poured into a corresponding shape in which projections, pins or the like, which form the openings 11 in the plastic film 12. In this case, it is also possible to produce the plastic film 12 forming the strip material 7 by means of a generative production method, for example by means of selective laser sintering or 3D printing. In such a case, the openings 11 can already be omitted in the manufacture of the plastic film 12, so that, for example, in the case of laser sintering at the point at which the openings 11 should be that the plastic film 12 forming material is not sintered.

In particular, when using the plastic film 12 for the strip material 7, round, oval, triangular and / or polygonal shapes can be used in addition to the rectangular or square shapes of the openings 11. In the case of a round shape of the opening 11, the inside width thereof is formed by the diameter, while in the case of a triangular shape of the opening 11, the longest leg of the triangle forms the clear width. For the other forms, this applies analogously in a comprehensible way.

The suction belt 1 has a very large number of openings 11. In this way it is prevented that all of the openings 11 are clogged by the tobacco or the filter material, so that always enough free openings 11 are available and fine dust or very small tobacco fibers are sucked through the suction belt 1 and not get into the cigarette.

Preferably, the two edges of the strip material 7 denoted by the reference numeral 13 are made substantially straight. By the term "substantially straight" is meant that the two lateral edges 13 of the strip material 7 do not have recesses with a size of more than 0.3 mm. This straightening of the edges 13 prevents the tobacco from getting past the suction belt 1 into the vacuum chamber 3. The size of the FIGS. 3 and 4 depressions not shown can be adapted to the above-explained size of the clear width of the openings 11 in order to achieve a certain degree of filtering by the suction belt 1. For the maximum size of the recesses at the edges 13 of the strip material 7 and the percentage minimum portion of the recesses, which have this size, the same applies with reference to the openings 11.

Depending on the embodiment of the strip material 7 of the suction belt 1, this straightening of the lateral edges 13 can take place in different ways. For example, in the case of using the fabric 8 may be provided for the strip material 7, that at least the two laterally outer warp threads 9 of the fabric 8 consist of a multifilament yarn. In this case, the binding of the respective weft thread 10 adheres to the structure, so that a much straighter band edge is formed. Furthermore, in the case of using a monofilament thread for the warp threads 9, the monofilament may be finely crimped, so that the respective weft thread 10 always lies in the depression resulting from this crimp and closes it.

Additionally or alternatively it can be provided that in the edge region of the strip material 7 additional material is applied, for example by means of fusing, welding, printing, coating, application, filling and / or extrusion. In this case, the already existing material is used in the fusion, whereas in welding, printing, coating, application, filling or extruding additional material is used. The straight edge in the region of the edges 13 can then be produced for example by means of trimming, grinding, or the like.

For example, one of the warp threads 9 can also have certain pigments so that it can be melted with laser radiation in order to form a closed region in the region of the edges 13, so that the edges 13 are straight and with recesses having a maximum clear width of 0, 3 mm can be achieved. By heating, the strip material 7 can be closed in the region of the edges 13 in order to fill the edge roughness.

In principle, it would also be possible to close the strip material 7 in the region of the edges 13 with a 3D printer or a similar device. In this case, if necessary, could be dispensed with a trimming or grinding.

In the case of using a plastic film 12 for the strip material 7, this can be prepared so that the lateral edges 13 thereof are already substantially straight.

In principle, it would also be possible to use the described straightening of the edges 13 of the suction belt 1 even with such suction belts, in which the openings 11 have a larger inside width than 0.3 mm. The feature that the two lateral edges 13 of the strip material 7 are made essentially straight is therefore not necessarily coupled to the feature that at least 75% of all openings 11 have a clear width of 0.3 mm or less.

As an alternative to the use of the fabric 8 or the plastic film 12 for the strip material 7, the strip material 7 may also comprise a knitted fabric, a knitted fabric and / or a scrim or combinations of these textile fabrics.

Furthermore, it would also be possible to use the suction belt 1 as a garniture belt for forming filters. Through the openings 11 in this case the hot steam can pass through the belt.

Claims (15)

Suction belt (1) for transporting tobacco and / or filter material in the manufacture of cigarettes, having a flat, ring-shaped strip material (7) and having a plurality of openings (11) distributed over the surface of the strip material (7),
characterized in that
at least 75% of all openings (11) have a clear width of 0.3 mm or less. Suction belt according to claim 1,
characterized in that
at least 75% of all openings (11) have a clear width of 0.25 mm or less, preferably 0.22 mm or less, more preferably 0.2 mm or less, even more preferably 0.17 mm or less, even more preferably 0.15 mm or less. Suction belt according to claim 1 or 2,
characterized in that
at least 80%, preferably at least 85%, more preferably at least 90%, of all openings (11) have a clear width of 0.3 mm or less. Suction belt according to claim 1, 2 or 3,
characterized in that
the strip material (7) has a fabric (8) with warp threads (9) and weft threads (10), the openings (11) being located between the warp threads (9) and the weft threads (10). Suction belt according to claim 4,
characterized in that
the two opposite surfaces of the band material (7) are made substantially symmetrical to each other, wherein the fabric (8) is bound with a plain weave and / or a twill weave. Suction belt according to claim 4 or 5,
characterized in that
the warp threads (9) and / or the weft threads (10) have a thickness of about 0.25 mm or less. Suction belt according to claim 1, 2 or 3,
characterized in that
the band material (7) comprises a knitted fabric, knitted fabric, scrim, or a combination thereof. Suction belt according to claim 1, 2 or 3,
characterized in that
the strip material (7) has a flat plastic film (12) in which the openings (11) are located. Suction belt according to one of claims 1 to 8,
characterized in that
the openings (11) have a quadrangular, rectangular, round, oval, triangular and / or polygonal shape. Suction belt according to one of claims 1 to 9,
characterized in that
the two lateral edges (13) of the strip material (7) are made substantially straight. Suction belt according to claim 10,
characterized in that
the two lateral edges (13) of the strip material (7) are made straight so that they have no recesses with a clear width of more than 0.3 mm. Suction belt according to claim 10 or 11,
characterized in that
the straightening of the two lateral edges (13) of the strip material (7) by means of fusing, welding, printing, coating, application, filling, extrusion, trimming and / or grinding is made. Suction belt according to claims 4 and 10 or 11,
characterized in that
the straightening of the two lateral edges (13) of the strip material (7) results from the fact that at least the two laterally outer warp threads (9) consist of a multifilament yarn. Suction belt according to one of claims 1 to 13,
characterized in that
the strip material (7) has two ends, which are connected in a connecting region by means of laser welding to the endless strip material (7). Method for producing a suction belt according to one of claims 10 to 12,
characterized in that
the two lateral edges (13) of the strip material (7) are straightened by fusing, welding, printing, coating, applying, filling, extruding, trimming and / or grinding.

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