Crimping roller, crimping roller pair, crimping device and machine of the tobacco processing industry and method for crimping a flat web and producing a strand, and rod-like articles
Patent Information
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- KORBER TECHNOLOGIES GMBH
- Filing Date
- 2024-08-02
- Publication Date
- 2026-05-13
Smart Images
Figure EP2024072035_27022025_PF_FP_ABST
Abstract
Description
[0001] Crimping roller, pair of crimping rollers, crimping device and machine of the tobacco processing industry as well as method for crimping a flat strip and producing a strand, rod-shaped articles
[0002] Description
[0003] The invention relates to a crimping roller for a crimping device in the tobacco processing industry, on whose outer surface, closed, circumferential grooves and teeth are arranged alternately in the circumferential direction of the crimping roller. Furthermore, the invention relates to a pair of crimping rollers and a crimping device in the tobacco processing industry. The invention also relates to a machine in the tobacco processing industry comprising a crimping device. Furthermore, the invention relates to a method for crimping a flat strip and a method for producing a rod in the tobacco processing industry. Finally, the invention relates to a rod-shaped article in the tobacco processing industry.
[0004] Flat webs are used for various purposes in the tobacco processing industry and are often processed into an infinitely long strand in a continuous process. Rod-shaped segments or articles for the tobacco processing industry can be produced from such a strand. For example, the flat web can be a paper web, and the segments produced from a corresponding strand are paper filters or paper filter segments. Other examples in which a rod-shaped segment is produced from a strand in the tobacco processing industry are the processing of a flat web made of reconstituted tobacco material (RECON) or PLA film. The rod-shaped segments cut to length from a corresponding strand can be used or employed as tobacco segments or as cooling segments in so-called HNB articles (for "Heat-Not-Burn"), which are also referred to as THP articles (for "Tobacco-Heated-Product").Such products from the tobacco processing industry are heated rather than burned. As a result of the heating, the ingredients of the tobacco material are released and made available for consumption via a stream of air.
[0005] Important process steps in processing the flat sheet into a strand, from which, for example, one of the rod-shaped articles mentioned above can be cut to length, include the forming of the flat sheet from a flat, spread-out state into a folded or gathered intermediate state and the subsequent compression into a strand with an essentially round cross-section. In order to facilitate the gathering of the flat sheet from the flat, spread-out state into the gathered intermediate state and also the further processing into a strand, it is known to crimp the flat sheet. During crimping, the material of the flat sheet is deliberately weakened, deformed or even separated in sections along crimp lines. The crimp lines can run in the lengthwise direction of the flat sheet (longitudinal crimping) or in a direction transverse to the lengthwise direction (transverse crimping).
[0006] The flat sheet is processed, i.e., crimped, in an active zone between a pair of intermeshing crimping rollers. The crimping rollers, for example, introduce crimp lines extending in the longitudinal direction of the flat sheet into the endless sheet. The material of the flat sheet can be stretched along the crimp lines, for example to achieve targeted material weakening along the crimp lines. The flat sheet can also be given a three-dimensional structure in a plane perpendicular to its longitudinal direction, i.e., deformed, for example, into a wave-like or zigzag shape. The three-dimensional structure facilitates the gathering of the flat sheet transverse to its longitudinal direction and also the subsequent strand formation. A crimping device is known, for example, from EP 3 624 615 B1.
[0007] Another crimping device is known from WO 2021 / 136612 A1. This device evaluates the properties of the crimped flat strip, and depending on these properties, a crimp depth, which is a measure of how far or deep the crimping rollers mesh, is changed.
[0008] It is an object of the invention to provide a crimping roller for a crimping device, a pair of crimping rollers, a crimping device and a machine in the tobacco processing industry, as well as a method for crimping a flat web, a method for producing a strand and a rod-shaped article in the tobacco processing industry, wherein a quality of the crimping of the flat web is to be improved with regard to the product properties of a rod-shaped article in the tobacco processing industry produced from a flat web.
[0009] The problem is solved by a crimping roller for a crimping device in the tobacco processing industry, on whose preferably one-piece outer surface grooves and teeth are arranged alternatingly in the circumferential direction of the crimping roller, wherein the crimping roller is designed to be rotatable about a rotation axis, wherein this crimping roller is further developed in that the grooves have a groove base curved parallel to the rotation axis and the teeth have a tooth head that is flat in at least sections. The grooves and teeth of the crimping roller are arranged alternately in an axial direction of the rotation axis and in particular directly next to one another. The teeth and grooves of the crimping roller are closed in the circumferential direction, i.e. always at the same axial position of the rotation axis, i.e. along the entire circumference. The grooves and teeth are each at a constant distance from the rotation axis at their axial position.The crimping roller is therefore, in particular, a body that is rotationally symmetrical with respect to its axis of rotation.
[0010] Crimping rollers with various profiles are known in the tobacco processing industry. However, it has become apparent that no profile currently exists that is suitable for a wide variety of flat webs used in the tobacco processing industry, meaning that equally good crimping results can be achieved for different flat webs.
[0011] It has been found that the crimping roller according to aspects of the invention is advantageously suitable for crimping different flat webs, in particular flat webs made of different materials from the tobacco processing industry. For example, flat webs made of paper can be advantageously crimped. The flat web can be either a single-layer or a multi-layer flat web made of paper. Furthermore, the flat web can be a single-layer or multi-layer web made of a nonwoven material, in particular a nonwoven material made of paper. The flat web can also be a PLA (polylactide) film or a tobacco film. The tobacco film can be produced using the slurry process (also referred to as CLT (cast leaf tobacco) film) or it can be produced using the paper process. The aforementioned flat webs from the tobacco processing industry are merely examples and not exhaustive.The crimping roller according to aspects of the invention has proven suitable for crimping these materials. Thus, the profile of the crimping roller is universally applicable to a wide variety of materials used in the tobacco processing industry. Rod-shaped articles or segments used in the tobacco processing industry, which are produced from a flat web crimped with such a crimping roller, exhibit advantageous properties. For example, only minor fluctuations in tensile strength occur during ongoing production. In other words, the crimping roller can be used to achieve a very consistent manufacturing process in which high-quality products can be continuously manufactured. This is advantageous, for example, when a filter or filter segment is produced from a paper web, as an example of a flat web used in the tobacco processing industry. A tensile strength that is as constant as possible is desirable for paper filters or paper filter segments.Small fluctuations in draw resistance are also advantageous when processing PLA or tobacco foil. Rod-shaped segments made from crimped tobacco foil or PLA are often used in HNB products. Small fluctuations in the draw resistance of these segments can improve the overall quality of the HNB product.
[0012] According to an advantageous embodiment, the crimping roller is developed in that the tooth tips of the teeth each have a flat section, wherein the flat sections extend in an imaginary cylindrical surface constructed around the axis of rotation. According to a further embodiment, the crimping roller is developed in that the groove base, viewed in a plane in which the axis of rotation runs, describes a curve whose gradient is continuous. In this context, it is provided in particular that the groove base, viewed in the said plane, describes a conic section, in particular a circular arc, preferably with a radius of 0.15 mm to 4.0 mm, particularly preferably of 0.18 mm to 0.35 mm, an elliptical arc or a parabola.
[0013] The combination of a flattened tooth tip and a round, particularly circular, groove base has proven to be an advantageous combination. With this type of crimping roller profile, a wide variety of different flat webs can be processed. The flat web is compressed in the area of the groove base. The flat web is stretched in the area of the tooth flanks. The flat sections or upper sides of the teeth ensure that the flat web is only slightly stretched or not stretched at all in this area. In addition, kinks or targeted material weakenings can be introduced into the flat web at the transition between the tooth flanks and the flat sections, even leading to openings, cracks, or the like running in sections along the length of the flat web.This targeted treatment of the flat sheet, achieved with the help of the crimping roller—section-by-section compression, weakening, and deformation or tearing in sections viewed transversely—leads to a flat sheet structure that has a positive effect on subsequent processing steps. For example, the flat sheet can be easily gathered and processed into a strand. Crimping thus has a positive effect on the properties of a rod-shaped segment produced from such a flat sheet.
[0014] For example, the material weakenings deliberately introduced in certain sections, such as cracks or perforations, result in channel formation in a segment made from such a flat web being reduced or even prevented. While it is desirable for the segment to have longitudinal channels through which an air stream can flow in the longitudinal direction of the segment, what is undesirable are channels that extend along the entire length of the segment. In the area of these continuous channels, there is only a reduced interaction between the air stream and the material of the segment. The transfer of aerosol escaping from the flat web into the air stream is correspondingly low, for example. This applies when a tobacco foil is processed as the flat web. The same applies to the filter effect if a paper web is processed as the flat web.If such a paper filter has continuous channels along its entire length, the filtering efficiency in this area will be low. The aforementioned measures can reduce channel formation, thereby improving the quality of a segment of the tobacco processing industry produced from such a crimped flat sheet.
[0015] According to a further advantageous embodiment, the crimping roller is developed in such a way that a flank angle of the teeth lies between 15° and 40°, in particular between 16° and 22° or between 25° and 35°. The said flank angle is measured between the two flanks of a tooth. Viewed in a plane in which the rotational axis of the crimping roller extends, the two flanks of a tooth enclose an angle that lies within the said interval. The flank angle is an opening angle that is enclosed by the two flanks of the teeth in the said plane. The intervals for the flank angle have proven advantageous with regard to the desired properties of the crimped flat strip.
[0016] According to one embodiment, the crimping roller is further developed in that, viewed in a direction parallel to the axis of rotation, the tooth tip has a tooth tip width, preferably between 0.05 mm and 0.7 mm, in particular between 0.08 mm and 0.2 mm or between 0.4 mm and 0.6 mm, and the tooth tip together with the adjacent groove has a structural width, wherein the tooth tip width is between 8% and 50%, in particular between 10% and 30% or between 25% and 38%, of the structural width. The aforementioned ratios between the tooth tip width and the structural width, which is the sum of the tooth tip width and the width of the adjacent groove, have also proven advantageous.
[0017] Both with regard to the aforementioned flank angle of the teeth and with regard to the aforementioned ratio between tooth tip width and structure width, the previously mentioned advantages could be achieved for different materials of the flat strip to be crimped. According to a further advantageous embodiment, it is further provided that the tooth tip is sharp-edged or has a chamfer or rounding at its edges where a surface of the crimping roller transitions from the tooth tip into the adjacent groove, or that the number of tooth tips is greater than 150 or 200 or 250 or 300. The transition between the numbered head and the adjacent groove can be designed with more or less sharp edges. While a sharp transition promotes the formation of deformations and even cracks in the flat strip, a rounded transition will significantly reduce this effect.In this context, a chamfer can be a good interim solution to achieve deformation or cracking on the one hand, but not to allow these to become too severe.
[0018] According to a further advantageous embodiment, the crimping roller is developed in that a surface of the crimping roller has an average surface roughness (Rz) of better than Rz=10, in particular better than Rz=8 and furthermore in particular better than Rz=6. Furthermore, it is particularly provided that the surface of the crimping roller has a surface roughness of Rz=4. The surface roughness of the crimping roller determines, among other things, the intensity of the interaction between the crimping roller and the flat web to be processed. Great roughness leads to high frictional resistance between the surface of the crimping roller and the flat web. Accordingly, relative movement of the flat web to the surface of the crimping roller is avoided or prevented. A lower surface roughness of the crimping roller, on the other hand, leads to low frictional resistance and thus allows more relative movement between the surface of the crimping roller and the flat web.This can be a desirable effect. A relative movement of the flat strip relative to the surface of the crimping roller, for example, a sliding of the flat strip transversely to its longitudinal direction, can be desirable, as the crimping process always results in an increase in the width of the flat strip. The flat strip is wider when crimped than when uncrimped. In other words, it is necessary for the outer regions of the flat strip to move transversely to the longitudinal direction of the flat strip during the crimping process in order to compensate for the increase in width caused by the crimping process. This evasive movement is favored by a low surface roughness of the crimping roller.
[0019] The object is further achieved by a crimping roller pair comprising a first and a second crimping roller according to one or more of the aforementioned embodiments, wherein the first and the second crimping roller of the crimping roller pair are arranged such that the teeth of the first crimping roller engage in the grooves of the second crimping roller and vice versa, wherein in particular the crimping roller pair with the intermeshing teeth of the first crimping roller and the second crimping roller has a crimping depth between 100 pm and 1100 pm, preferably between 150 pm and 400 pm or between 500 pm and 800 pm.
[0020] Such a pair of crimping rollers is ideal for processing a wide variety of flat webs used in the tobacco processing industry. In this regard, the pair of crimping rollers offers the same or similar advantages as those already mentioned with regard to the crimping roller itself, so repetition will be avoided.
[0021] The first and second crimping rollers of the crimping roller pair are arranged such that their rotational axes are aligned parallel to one another. Furthermore, the crimping roller pair has, in particular, a crimping depth control device with which a crimping depth can be adjusted. The crimping depth is a measure of how deeply the teeth of the first crimping roller engage in the grooves of the second crimping roller and vice versa. The crimping depth can be measured, for example, based on the distance between the tooth tips of the first crimping roller and the tooth tips of the second crimping roller, in a plane in which the two rotational axes of the crimping rollers extend. Preferably, the ratio of the structural width of the teeth minus twice the tooth width of the teeth to twice the crimping depth is greater than 1 or greater than 0.5.
[0022] A measure of the local deformation or the local stretching of the web material or the flat web is, for example, in particular the air permeability according to ISO 2965 of greater than 3000 CU (Coresta Unit) or 3500 CU or 4000 CU and / or the web thickness of the flat web of 50 pm to 600 pm, preferably between 400 pm and 600 pm, and / or a grammage between 20 g / m 2 and 100 g / m 2 , preferably between 40 g / m 2 and 80 g / m 2 .
[0023] The flat web is preferably a paper web or a paper web with a paper or cellulose content of more than 70%, 80%, or 90%. In particular, the flat web contains no tobacco or is designed as a tobacco-free paper web.
[0024] The object is further achieved by a crimping device in the tobacco processing industry for processing a flat web in the tobacco processing industry, comprising a flat web feed device, at least one crimping roller according to one or more of the aforementioned embodiments, a counter-bearing cooperating with the crimping roller, and a transfer device. The flat web feed device is configured to feed the flat web into an active zone between the at least one crimping roller and the counter-bearing cooperating with the crimping roller. The transfer device is configured to feed the crimped flat web from the active zone to a downstream processing device, in particular a strand-forming device.
[0025] The flat web feed device is particularly designed to feed the flat web as a continuous flat web. For this purpose, the flat web feed device comprises, for example, at least one reel holder and a reel changer, including a flat web joining device, for example, a splicer. The flat web joining device can connect an end of an outgoing flat web to a beginning of a new flat web, thus providing a continuous flat web for processing.
[0026] The active zone between the two crimping rollers is at least the area in which the two crimping rollers mesh, i.e., the grooves and teeth overlap when viewed in cross-section. This cross-section can be viewed in a plane in which the two rotational axes of the crimping rollers extend. To feed the flat web into the active zone, the flat web feed device has, for example, suitable and generally known web guide rollers or general web guides such as barks or chutes. The transfer device can also have suitable guide rollers or one or more of the aforementioned flat web guide devices to remove the crimped flat web from the active zone and feed it to the downstream processing device.
[0027] According to a further embodiment, the crimping device is further developed in that the counterbearing is a crimping roller according to one or more of the aforementioned embodiments, or in that the crimping device comprises a pair of crimping rollers according to the invention, as described above. According to such an embodiment, the crimping device comprises a pair of crimping rollers according to aspects of the invention.
[0028] The object is further achieved by a machine of the tobacco processing industry, comprising a crimping device with at least one crimping roller according to one or more of the aforementioned embodiments and with a counter bearing cooperating with the crimping roller or with a pair of crimping rollers described above.The machine of the tobacco processing industry further comprises: a flat web feed device which is configured to feed a flat web of the tobacco processing industry to an active area between the crimping roller and the counter bearing cooperating with the crimping roller, a transfer device and a strand forming device arranged downstream, wherein the transfer device is configured to remove the crimped flat web from the active area and feed it to the strand forming device and the strand forming device is configured to form a strand of the tobacco processing industry from the crimped flat web.
[0029] According to a further embodiment, the second crimping roller in such a machine of the tobacco processing industry is also designed according to one or more of the embodiments previously mentioned with regard to the crimping roller.
[0030] The tobacco processing machine can further comprise a cutting device with which segments for the tobacco processing industry are cut from the produced strand. These segments can be fed into further processing steps. For example, the segments can be combined with other segments to form rod-shaped articles for the tobacco processing industry. Such articles for the tobacco processing industry are, in particular, HNB articles.
[0031] Advantageously, the machine allows the tobacco processing industry to produce products of improved quality, for example, with regard to their draw resistance. The draw resistance of the rod-shaped products produced with such a machine remains very consistent throughout the production process. The origin of this quality improvement lies in the improved crimping quality of the flat strip used as the starting material in the tobacco processing industry.
[0032] The machine of the tobacco processing industry is advantageously further developed in that the counter-bearing is a crimping roller according to one or more of the aforementioned embodiments and the crimping roller and the counter-bearing are arranged such that the teeth of the crimping roller engage in the grooves of the counter-bearing with a crimping depth and vice versa, wherein the crimping device has a crimping depth control device which is designed and configured to change the crimping depth, wherein the crimping depth control device is further configured to receive a value of a draw resistance of a segment of the tobacco processing industry produced from the rod of the tobacco processing industry and to change the crimping depth according to a linear relationship depending on the value for the draw resistance.
[0033] The machine for the tobacco processing industry can furthermore comprise, in particular, a draw resistance measuring device with which the draw resistance is measured either on the rod or on rod-shaped segments cut from the rod produced by the machine. Likewise, the measured draw resistance value can be measured on a finished article in the tobacco processing industry, which has a segment cut from the rod produced by the machine. The profile of the crimping roller advantageously allows for the draw resistance to be adjusted by changing the crimping depth, whereby a linear relationship can advantageously be used as a basis. This considerably simplifies the control of the machine and permits simple and precise feedback quality assurance.
[0034] The object is further achieved by a method for crimping a flat web of the tobacco processing industry, comprising the following steps: feeding a flat web of the tobacco processing industry into an active area between a crimping roller which is designed according to one or more of the aforementioned embodiments and a counter bearing which cooperates with the crimping roller, crimping the flat web in the active area and removing the crimped flat web from the active area and transferring the crimped flat web to a downstream processing device, in particular to a strand forming device.
[0035] Furthermore, the object is achieved by a method for producing a rod in the tobacco processing industry, comprising the following steps: feeding a flat web from the tobacco processing industry into an active area between a crimping roller, in particular according to one or more of the aforementioned embodiments, and a counter-bearing interacting with the crimping roller, crimping the flat web in the active area, removing the crimped flat web from the active area and transferring the crimped flat web to a rod forming device arranged downstream, forming a rod in the rod forming device from the crimped flat web, wherein the flat web has a width B1 before the active area and a width B2 after the active area and wherein the ratio B1 / B2 is greater than 1.2 or 1.3.
[0036] This method is particularly further developed in that the counter bearing is a crimping roller according to one or more of the previously mentioned embodiments and the crimping roller and the counter bearing are arranged such that the teeth of the crimping roller engage in the grooves of the counter bearing with a crimping depth and vice versa, wherein the crimping depth is variable and / or is varied according to a linear relationship depending on a value for the draw resistance of a segment of the tobacco processing industry produced from the rod of the tobacco processing industry.
[0037] The same or similar advantages apply to the method for crimping the flat strip as well as to the method for producing the rod in the tobacco processing industry as have already been mentioned with regard to the crimping device and the machine in the tobacco processing industry, so that repetition will be avoided.
[0038] In particular, the method is further developed in that a paper web is crimped as the flat web. The flat web can be either a single-layer or a multi-layer paper web. Furthermore, the flat web can be a single-layer or multi-layer nonwoven web, in particular a paper nonwoven. The flat web can also be a PLA (polylactide) film or a tobacco film. The tobacco film can be produced using the slurry process (also referred to as CLT (cast leaf tobacco) film) or it can be produced using the paper process.
[0039] The strand produced by the tobacco processing industry is in particular a filter strand.
[0040] The object is further achieved by a rod-shaped article of the tobacco processing industry, comprising at least one rod-shaped segment, which is produced by cutting to length a strand produced according to a method according to one or more of the aforementioned embodiments.
[0041] Such a rod-shaped article advantageously exhibits improved properties with regard to the consistency of the tensile strength value. In other words, process-related fluctuations in tensile strength must be accepted, which improves the quality of the rod-shaped article. The rod-shaped segment is, in particular, a filter segment, and furthermore, in particular, a filter segment made of paper, i.e., a paper filter segment.
[0042] Further features of the invention will become apparent from the description of embodiments of the invention together with the claims and the accompanying drawings. Embodiments of the invention may incorporate individual features or a combination of several features.
[0043] The invention is described below, without limiting the general inventive concept, using exemplary embodiments with reference to the drawings, whereby express reference is made to the drawings for all details of the invention not explained in more detail in the text. They show:
[0044] Fig. 1 is a schematically simplified representation of a machine of the tobacco processing industry comprising a crimping device with a pair of crimping rollers, which has a crimping roller according to an embodiment,
[0045] Fig. 2 shows a schematically simplified cross-section of a profile of a crimping roller according to an embodiment,
[0046] Fig. 3 and 4 schematically simplified side views of a sectionally shown pair of crimping rollers, according to two embodiments, and
[0047] Fig. 5 and 6 also show schematically simplified side views of crimping roller pairs shown in sections, wherein the cross section shows a profile of the crimped flat track in the effective area between the crimping rollers.
[0048] Within the scope of the invention, features marked with “in particular” or “preferably” are to be understood as optional features.
[0049] In the drawings, identical or similar elements and / or parts are provided with the same reference numbers, so that a repeated presentation is omitted.
[0050] Fig. 1 shows a simplified schematic representation of a machine 2 of the tobacco processing industry. The machine 2 has a crimping device 4 with a crimping roller 6 and a counter-bearing 8 that interacts with the crimping roller 6. The counter-bearing 8 is, in particular, structurally identical to the crimping roller 6. In this case, the crimping roller 6 and the counter-bearing form a crimping roller pair 10. The machine 2 further has a flat web feed device 12 that is designed to feed a flat web 14 of the tobacco processing industry to an active area 16 between the crimping roller 6 and the counter-bearing 8 in a transport direction T. The flat web 14 is, for example, a paper web.
[0051] The crimping roller 6 interacts with the counterbearing 8 in the active area 16; for example, the crimping roller 6 engages the counterbearing 8. The flat web feed device 12 has, for example, a reel 18 on which the flat web 14 is provided. In an alternative embodiment, the flat webs or paper webs are provided from a paper bale, with the flat webs or paper webs being laid on top of one another in a meandering pattern (festooning).
[0052] To enable a continuous production process, the flat web feed device 12 can further comprise a reel changer (not shown), in particular including a flat web connecting device, for example a splicer. The flat web connecting device can be configured to connect a run-out end of one flat web to a start of another flat web, so that the flat web 14 can be continuously fed into the crimping device 4 and the units further downstream in the transport direction T. For example, the flat web feed device 12 comprises, in addition to the reel 18, one or more transport rollers 20, with which the flat web 14 can be fed to the active area 16.
[0053] The flat web 14 is crimped in the active area 16. The crimping device 4 is designed, for example, as a longitudinal crimper. The crimping device 4 introduces crimp lines running in the longitudinal direction of the flat web 14 into the flat web 14. Along the crimp lines, the material of the flat web 14 is, for example, specifically weakened, deformed, or even separated in sections. The flat web 14 leaves the crimping device as a crimped flat web 22. This is fed by a transfer device 24, represented for example by two transport rollers 20, to a strand forming device 26 arranged downstream. The transfer device 24 can also be designed, for example, as a chute or trough to guide the crimped flat web 22, wherein the transfer device 24 can also be configured to gather the crimped flat web 22 transversely to its longitudinal direction.The transfer device 24 removes the crimped flat web 22 from the active area 16 and feeds it to the strand forming device 26. The strand forming device 26 is configured to form a strand 28 for the tobacco processing industry from the crimped flat web 22. For example, the strand forming device 26 has a formatting unit 30 (not described in detail) for this purpose, which has a formatting channel and forms the strand 28 from the crimped flat web 22 in a manner known per se. The machine 2 further has, for example, a knife device 32 configured to cut individual segments 34 from the strand 28. The segments 34 can be further processed with additional segments to form rod-shaped articles 68 for the tobacco processing industry, for example, to form HNB articles. This further processing is indicated schematically with an arrow.
[0054] For example, the flat web 14 is a paper web from which a paper filter rod is made. In this case, the cut-to-length segments 34 are paper filter segments, which can be combined with tobacco rods, for example, and further processed into conventional rod-shaped articles 68 of the tobacco processing industry. The paper filter segments can also be further processed with further segments to form an HNB article as a rod-shaped article 68 of the tobacco processing industry. The flat web 14 is, for example, a single-layer or multi-layer paper web. The flat web 14 can be a paper web made of a single-layer or multi-layer nonwoven material, in particular of paper. The flat web 14 can also be a flat web made of reconstituted tobacco material, for example a web made of reconstituted tobacco material produced by the slurry process or by the paper process.In such a case, a tobacco rod 28 is produced from the flat web 14, from which individual tobacco segments or tobacco rods would be cut to length as segments 34. These can also be combined with other segments, for example to form a HNB article, and further processed. The flat web 14 can be a PLA film, from which a rod 28 of crimped PLA film is produced. The segments 34 cut from such a rod 28 can serve as cooling sections in a HNB article and can be combined with other segments and further processed to form a HNB article. The machine 2 is advantageously suited for processing different flat webs 14.
[0055] In the following, it is assumed, for example, that the counter bearing 8 is constructed identically to the crimping roller 6.
[0056] Fig. 2 shows a schematically simplified cross-section of a partially illustrated profile of the crimping roller 6. The crimping roller 6 has, on its outer surface 36, alternating closed circumferential grooves 38 and teeth 40 in the circumferential direction of the crimping roller 6. The crimping roller 6 is designed to be rotatable about a rotation axis 42, which is shown in Fig. 2 with a dash-dotted line and whose position is merely schematic.
[0057] In the crimping device 4, which has the machine 2 shown in Fig. 1, the crimping roller 6 and the counter bearing 8 are arranged such that the teeth 40 of the crimping roller 6 engage in the grooves 38 of the counter bearing 8, and vice versa.
[0058] In the profile of the crimping roller 6 shown in Fig. 2, the grooves 38 have a curved groove base 44. The teeth 40 have a flat tooth tip 46 with a flat section 48. The flat sections 48 of the tooth tips 46 extend in an imaginary cylindrical surface constructed around the axis of rotation 42. The flat sections 48 are therefore each cylindrical surface-shaped. The groove base 44, viewed in a plane in which the axis of rotation 42 runs and which corresponds at least approximately to the drawing plane of Fig. 2, describes a curve whose gradient is continuous. In other words, the gradient of the groove base 44 does not change suddenly. In particular, the curved groove base 44 is not acute-angled or otherwise exhibits no abrupt changes in gradient in the plane under consideration.The groove base 44, viewed in the described plane, has the shape of a conic section and describes, for example, a circular arc, an elliptical arc, or a parabola. In the illustrated embodiment, the groove base 44 describes a circular arc.
[0059] The teeth 40 of the crimping roller 6 have a flank angle α that lies between 15° and 40°, in particular between 20° and 35°. The flank angle α is the angle between the lines indicated by a dashed line in Fig. 2, which, also viewed in the described plane, run in the flanks 50 of the teeth. The flank angle α is measured between the opposing flanks 50 of the teeth 40. The crimping roller 6 is further configured such that, in a direction parallel to the rotation axis 42, the tooth tip 46 has a tooth tip width 52, and the tooth tip 46, together with the adjacent groove 38, has a structural width 54. The tooth tip width 52 is between 20% and 50%, in particular between 30% and 40%, furthermore in particular between 35% and 40% of the structural width 54.
[0060] Furthermore, the crimping roller 6 is designed, for example, such that the tooth head 46 has sharp edges at its edges 56, where a surface 58 of the crimping roller 6 transitions from the tooth head 46 into the adjacent groove 38. Furthermore, a chamfer or a rounding with a small radius can be provided, for example, on this edge 56. A surface 58 of the crimping roller 6 has, for example, an average surface roughness of Rz=10 or better. Furthermore, the surface 58 has an average surface roughness of better than Rz=8 or better than Rz=6. The surface 58 of the crimping roller 6 is considered to be, in particular, the groove base 44, the flanks 50 and the tooth head 46 or the flat section 48 of the tooth head 46.
[0061] Fig. 3 shows a schematically simplified perspective side view of a section of a pair of crimping rollers 10. A first crimping roller 6a and a second crimping roller 6b are arranged such that the teeth 40 of the first crimping roller 6a engage the grooves 38 of the second crimping roller 6b, and vice versa. The two crimping rollers 6a, 6b are arranged relative to one another such that the two crimping rollers 6a, 6b engage with each other at a crimping depth of 60.
[0062] Fig. 4 shows another pair of crimping rollers 10, comprising a first crimping roller 6a and a second crimping roller 6b. These two crimping rollers 6a, 6b are also arranged such that the teeth 40 of the first crimping roller 6a engage the grooves 38 of the second crimping roller 6b and vice versa. The difference between the pair of crimping rollers 10 shown in Fig. 3 and that shown in Fig. 4 lies in the width of the tooth heads 46. While the teeth 40 of the crimping rollers 6a, 6b according to the embodiment shown in Fig. 3 have a comparatively small tooth head width 52 (see also Fig. 2), the crimping rollers 6a, 6b of the pair of crimping rollers 10 shown in Fig. 4 are designed with a relatively larger tooth head width 52. The tooth head width 52 can have an influence on the deformation and stretching of the flat web 14 taking place in the active area 16 between the crimping rollers 6a, 6b, i.e. in particular in an area in which the crimping rollers 6a, 6b engage with each other.This is shown in Fig. 5 and 6, which are schematically simplified side views of the first and second crimping rollers 6a, 6b, shown in sections. The flat track 14 is shown in cross-section in an active region 16 between the crimping rollers 6a, 6b. Fig. 5 corresponds approximately to the situation known from Fig. 3. The first crimping roller 6a and the second crimping roller 6b are designed with a relatively small tooth tip width 52. The course of the flat track 14 in the active region 16 between the crimping rollers 6a, 6b is shown schematically and in a simplified manner. In the region of the tooth tips 46, the flat track 14 is locally deformed, for example bent, so that it takes on a zigzag shape. In the region between the adjacent tooth tips 46 of the first and second crimping rollers 6a, 6b there is an expansion region 62 in which the flat track 14 is expanded.The extent of this stretching and the deformation introduced into the flat track 14 at the edges 56 of the tooth tips 46 can be varied via the tooth tip width 52. This is demonstrated by the exemplary embodiment shown in Fig. 6, which roughly corresponds to the situation known from Fig. 4. The two crimping rollers 6a, 6b have a larger tooth tip width 52 compared to the exemplary embodiment in Fig. 5. This leads to a greater stretching of the flat track 14 in the stretching region 62 for the same crimping depth 60. A greater deformation of the flat track 14 also occurs in the region of the edges 56 of the tooth tips 46.
[0063] The tobacco processing machine 2, as shown in Fig. 1, can be provided with a crimping depth control device 64 that is designed and configured to change the crimping depth 60. The crimping depth control device 64 can further be configured to receive a value of a draw resistance of a tobacco processing segment 34 produced from the tobacco processing strand 28. Based on the draw resistance value, the crimping depth control device 64 changes the crimping depth 60 according to a linear relationship. In other words, the crimping depth 60 can be adjusted to change the draw resistance of the produced segments 34. The machine 2 has, for example, a draw resistance measuring device 66 for measuring the draw resistance.Their measured value M can be provided to the crimping depth control device 64 so that a feedback control of the crimping depth is possible as a function of the measured tensile resistance of the segments 34.
[0064] From the segments 34, a rod-shaped article 68 can be produced through further processing steps, indicated by an arrow, which comprises a segment 34 that is obtainable by cutting the produced strand 28 to length. This rod-shaped segment 34 is, for example, a filter segment, furthermore, for example, a paper filter segment.
[0065] All mentioned features, including those revealed solely in the drawings as well as individual features disclosed in combination with other features, are considered essential to the invention, both individually and in combination. Embodiments of the invention may be fulfilled by individual features or a combination of several features.
[0066] List of reference symbols
[0067] 2 Machine of the tobacco processing industry
[0068] 4 Crimping device
[0069] 6 Crimping roller
[0070] 6a first crimping roller
[0071] 6b second crimping roller
[0072] 8 counter bearings
[0073] 10 pairs of crimping rollers
[0074] 12 Flat web feed device
[0075] 14 flat track
[0076] 16 Effective range
[0077] 18 reels
[0078] 20 transport roller
[0079] 22 crimped flat strip
[0080] 24 Transfer device
[0081] 26 Strand forming device
[0082] 28 strands
[0083] 30 format units
[0084] 32 knife apparatus
[0085] 34 segments
[0086] 36 lateral surface
[0087] 38 grooves
[0088] 40 teeth
[0089] 42 Rotation axis
[0090] 44 groove base
[0091] 46 tooth head
[0092] 48 flat section
[0093] 50 flank
[0094] 52 tooth head width
[0095] 54 structure width
[0096] 56 edge
[0097] 58 Surface
[0098] 60 Crimping depth 2 Elongation range 4 Crimping depth control device 6 Tensile resistance measuring device 8 Rod-shaped article
[0099] T Transport direction
[0100] M measured value a flank angle
Claims
Patent claims 1. Crimping roller (6) for a crimping device in the tobacco processing industry, on the preferably integrally formed outer surface (36) of which grooves (38) and teeth (40) are arranged alternately in the circumferential direction of the crimping roller (6) in a closed manner, the crimping roller (6) being designed to be rotatable about an axis of rotation (42), characterized in that the grooves (38) have a groove base (44) curved parallel to the axis of rotation (42) and the teeth (40) have a tooth head (46) which is flat at least in sections.
2. Crimping roller (6) according to claim 1, characterized in that the tooth heads (46) of the teeth (40) each have a flat section (48), wherein the flat sections (48) extend in an imaginary cylinder surface constructed around the rotation axis (42).
3. Crimping roller (6) according to claim 1 or 2, characterized in that the groove base (44), viewed in a plane in which the axis of rotation (42) runs, describes a curve whose gradient is continuous.
4. Crimping roller (6) according to claim 3, characterized in that the groove base (44), viewed in the plane, describes a conical section, in particular a circular arc, preferably with a radius of 0.15 mm to 0.4 mm, particularly preferably from 0.18 mm to 0.35 mm, an elliptical arc or a parabola.
5. Crimping roller (6) according to one of claims 1 to 4, characterized in that a flank angle (a) of the teeth (40) is between 15° and 40°, in particular between 16° and 22° or between 25° and 35°.
6. Crimping roller (6) according to one of claims 1 to 5, characterized in that viewed in a direction parallel to the rotation axis (42), the tooth head (46) has a tooth head width (52), preferably between 0.05 mm and 0.7 mm, in particular between 0.08 mm and 0.2 mm or between 0.4 mm and 0.6 mm, and the tooth head (46) together with the adjacent groove (38) has a structural width (54), wherein the tooth head width (52) is between 8% and 50%, in particular between 10% and 30% or between 25% and 38%, and in particular the structural width (54).
7. Crimping roller (6) according to one of claims 1 to 6, characterized in that the tooth head (46) is sharp-edged or has a chamfer or rounding at its edges (56), at which a surface of the crimping roller (6) transitions from the tooth head (46) into the adjacent groove (38), or the number of tooth heads is greater than 150 or 200 or 250 or 300.
8. Crimping roller (6) according to one of claims 1 to 7, characterized in that a surface (58) of the crimping roller (6) has an average roughness depth (Rz) of better than Rz=10, in particular of better than Rz=8 and furthermore in particular of better than Rz=6.
9. Crimping roller pair (10), comprising a first and a second crimping roller (6a, 6b), each according to one of claims 1 to 8, wherein the first and the second crimping roller (6a, 6b) of the crimping roller pair (10) are arranged such that the teeth (40) of the first crimping roller (6a) engage in the grooves (38) of the second crimping roller (6b) and vice versa, wherein in particular the crimping roller pair (10) with the intermeshing teeth of the first crimping roller (6a) and the second crimping roller (6b) has a crimping depth between 100 pm and 1100 pm, preferably between 150 pm and 400 pm or between 500 pm and 800 pm.
10. Crimping roller pair (10) according to claim 9, characterized in that the ratio of the structural width of the teeth minus twice the tooth width of the teeth to twice the crimping depth is greater than 1 or greater than 0.
5.
11. Crimping device (4) of the tobacco processing industry for processing a flat web (14) of the tobacco processing industry, comprising a flat web feed device (12), at least one crimping roller (6) according to one of claims 1 to 8, a counter-bearing (8) interacting with the crimping roller (6) and a transfer device (24), wherein the flat web feed device (12) is designed to feed the flat web (14) into an active area (16) between the at least one crimping roller (6) and the counter-bearing (8) interacting with the crimping roller (6), and the transfer device (24) is designed to feed the crimped flat web (22) from the active area (16) to a downstream processing device, in particular a strand forming device (26).
12. Crimping device (4) according to claim 11, characterized in that the counter bearing (8) is a crimping roller (6) according to one of claims 1 to 8 or that the crimping device (4) has a pair of crimping rollers according to claim 9 or 10.
13. A machine (2) for the tobacco processing industry, comprising: a crimping device (4) with at least one crimping roller (6) according to one of claims 1 to 8 and with a counter-bearing (8) cooperating with the crimping roller (6) or with a pair of crimping rollers according to claim 9 or 10, a flat web feed device (12) which is designed to feed a flat web (14) for the tobacco processing industry to an active area (16) between the crimping roller (6) and the counter-bearing (8) cooperating with the crimping roller (6), a transfer device (24) and a strand-forming device (26) arranged downstream, wherein the transfer device (24) is designed to remove the crimped flat web (22) from the active area (16) and to feed it to the strand-forming device (26), and the strand-forming device (26) is designed to form a strand (28) for the tobacco processing industry from the crimped flat web (22). to shape.
14. Machine (2) according to claim 13, characterized in that the counter-bearing (8) is a crimping roller (6) according to one of claims 1 to 8 and the crimping roller (6) and the counter-bearing (8) are arranged such that the teeth (40) of the crimping roller (6) engage in the grooves (38) of the counter-bearing (8) with a crimping depth (60) and vice versa, wherein the crimping device (4) has a crimping depth control device (64) which is designed and configured to change the crimping depth (60), wherein the crimping depth control device (64) is further configured to determine a value of a draw resistance of a product produced from the rod (28) of the tobacco processing industry. segment (34) of the tobacco processing industry and to change the crimping depth (60) according to a linear relationship depending on the value for the draw resistance.
15. A method for crimping a flat strip (14) of the tobacco processing industry, comprising the following steps: Feeding a flat web (14) of the tobacco processing industry into an active area (16) between a crimping roller (6) according to one of claims 1 to 8 and a counter-bearing (8) cooperating with the crimping roller (6), crimping the flat web (14) in the active area (16) and removing the crimped flat web (22) from the active area (16) and transferring the crimped flat web (22) to a downstream processing device, in particular to a strand forming device (26).
16. A method for producing a rod (28) of the tobacco processing industry, comprising the following steps: Feeding a flat web (14) of the tobacco processing industry into an active zone (16) between a crimping roller (6), in particular according to one of claims 1 to 8, and a counter-bearing (8) cooperating with the crimping roller (6), crimping the flat web (14) in the active zone (16), removing the crimped flat web (22) from the active zone (16) and transferring the crimped flat web (22) to a downstream strand forming device (26), forming a strand (28) of the tobacco processing industry in the strand forming device (26) from the crimped flat web (22), wherein the flat web has a width B1 before the active zone and a width B2 after the active zone and wherein the ratio B1 / B2 is greater than 1.2 or 1.
3.
17. Method according to claim 16, characterized in that the Counter bearing (8) is a crimping roller (6) according to one of claims 1 to 8 and the crimping roller (6) and the counter bearing (8) are arranged such that the teeth (40) of the crimping roller (6) engage in the grooves (38) of the counter bearing (8) with a crimping depth (60) and vice versa, wherein the crimping depth (60) is variable and / or is varied according to a linear relationship as a function of a value for the draw resistance of a segment (34) of the tobacco processing industry produced from the strand (28) of the tobacco processing industry.
18. Rod-shaped article (68) of the tobacco processing industry comprising at least one rod-shaped segment (34) which is produced by cutting to length a strand (28) produced according to a method according to claim 16 or 17.