EP4640079A1 - Device and method for producing a rod in the tobacco industry - Google Patents

Abstract

The invention relates to a device and a method for producing a strand for the tobacco processing industry, in particular a tobacco strand. The device comprises a conveyor belt (17) having a lower run (17a) on which material (M) can be conveyed suspended along a material conveying direction (F). The device includes a suction device (18) for applying a vacuum to at least a section of the lower run (17a) to draw in the suspended material (M). The device includes a trimming device (19) with at least one trimming element (19a, 19b) for trimming the suspended material (M). An adjusting device (71, 72) is provided for adjusting a distance (A) between the at least one trimming element (19a, 19b) of the trimming device (19) and the lower run (17a) of the conveyor belt (17). The device has a control unit (60) configured to control the adjusting device (71, 72) during a strand production state of the device such that the adjusting device periodically changes the distance (A) between the at least one trimming element (19a, 19b) of the trimming device (19) and the lower run (17a) of the conveyor belt (17) according to a periodic distance change specified by the control unit over time or with a periodic component over time.

Description

The invention relates to a device and a method for producing a strand for the tobacco processing industry, in particular a tobacco strand. The invention further relates to a smokable article and an arrangement comprising several smokable articles.

For the strand production of material, especially tobacco, stranding machines, particularly cigarette stranding machines, are typically used, which feature a suction belt conveyor. A suction belt conveyor of a stranding machine in the tobacco processing industry typically has a conveyor belt, also known as a suction belt, which is usually perforated and subjected to negative pressure or suction air from above. In a suction area, individual pieces of material, especially tobacco and/or other material, are suctioned onto the conveyor belt from below in an airflow, so that a layer of the loose material accumulates or builds up on the underside of the conveyor belt and is held in place by the negative pressure applied from above. The conveyor belt typically moves through a guide channel with lateral channel walls, which defines a cross-section for the suctioned material. Such a suction belt conveyor is, for example, made of... DE102011082625A1 known.

Downstream of the suction belt conveyor, the strand-shaped material is typically moved into a formatting device where it is wrapped with a wrapping material, for example wrapping paper, in particular cigarette paper, and/or a foil, for example aluminum foil, and formed into a strand wrapped with wrapping material with a round or oval cross-section.

Smokeable articles, such as cigarettes, are typically manufactured in such a way that their free end, in particular the so-called burning end in the case of filter cigarettes, has a head reinforcement that prevents tobacco from falling out of the head. This head reinforcement consists of an area of higher tobacco density at the free end of the smokeable article. It is also known to provide a further, somewhat smaller head reinforcement at the other end of the head, in the case of filter cigarettes the so-called filter end, which adjoins the filter. To produce a head reinforcement, a continuously fed strand of material, as described above, from which the smokeable articles are manufactured, is compacted at regular intervals before being wrapped with the wrapping material, so that the material strand contains more material in these compacted areas than between these areas. After the strand is wrapped with the wrapping material, rod-shaped sections of single or multiple, typically double, lengths are successively cut off and further processed into smokable products such as cigarettes. The rod-shaped sections then have corresponding head reinforcements at their ends.

Typically, the tobacco strand, which is wound up on a suction conveyor, is trimmed using a trimming device. For example, in EP2241204A1 As described, such a trimming device typically has two trimmer discs with several recesses in the form of pockets on their outer surface. These trimmer discs are used to remove excess fibers from the material strand. The pockets serve to form the head reinforcements by introducing reinforcements into the material strand in sections. The pockets are arranged in such a way that they create areas with more material than in the rest of the strand, resulting in denser regions within the strand. These denser regions of the material strand form the head reinforcements. A paddle wheel is also typically provided to remove excess fibers from the trimmer discs.

Another method for creating a head reinforcement is achieved through so-called cam head reinforcement. In this process, the material is compacted with a cam at the positions designated for head reinforcement and then trimmed to the desired height using trimmer discs.

One problem with known methods for trimming and inserting head reinforcements is that when changing the type of smokable product being manufactured, the trimmer discs must be changed to ensure they are precisely matched. Changing trimmer discs is time-consuming and requires stopping the manufacturing process. Another problem is that manufacturing known trimmer discs is relatively complex and therefore relatively expensive. This can lead to significant costs, especially when a large number of trimmer discs are needed for the production of different smokable products.

Another problem is that adjusting the parameters of the head reinforcement, such as the width, height, and shape of the density distribution in the head reinforcement area, is only possible within certain limits, and particularly dependent on the achievable shapes of the pockets in the trimmer discs. Furthermore, the head reinforcement parameters cannot be changed during the manufacturing process in known devices. This can be particularly problematic when process parameters such as excess material, vacuum, material type (especially tobacco type), material moisture (especially tobacco moisture), and/or other parameters change. Since at least some of these and potentially other process parameters can vary during the manufacturing process, this can lead to inconsistent and therefore suboptimal head reinforcements, especially those that deviate from the desired shape.

The invention is therefore based on the objective of providing an improved solution that addresses the aforementioned problems. In particular, it is an objective of the invention to provide a solution with which the introduction of a desired density profile into a material strand is possible more precisely and variably.

According to a first aspect of the invention, the problem is solved by a device with the features of claim 1. The device is provided for the production of a strand for the tobacco processing industry, in particular a tobacco strand, comprising a conveyor belt having a lower run, wherein the conveyor belt is designed and arranged to convey material, in particular tobacco, suspended from the lower run of the conveyor belt along a material conveying direction, a suction device for applying a vacuum to at least a section of the lower run of the conveyor belt to draw the suspended conveyed material onto the lower run of the conveyor belt, a trimming device with at least one trimming element for trimming the material conveyed suspended from the lower run of the conveyor belt, and at least one adjusting device for adjusting a distance between the at least one trimming element of the trimming device and the lower run of the conveyor belt.

According to the invention, the device includes a control unit configured to control the at least one adjusting device during a strand production state of the device in such a way that the at least one adjusting device periodically changes the distance between the at least one trimming element of the trimming device and the lower run of the conveyor belt over time or changes it with a periodic component over time.

Accordingly, a device for producing a strand of tobacco is provided, in which, during the production of the strand, a periodic change in the distance between at least one trimming element and the lower run of a conveyor belt is carried out by means of at least one adjusting device, in particular to create a specific density profile of the strand. A control unit is provided for controlling this periodic change in distance by means of the at least one adjusting device, which controls the at least one adjusting device accordingly.

One advantage of such a device is that it allows for a significantly more flexible and variable adjustment of the material's density profile compared to known devices. This allows the material's density profile to be changed during the production of a strand. If the material's density profile needs to be changed, for example, because a different product with different parameters such as product length is required, If a product diameter or similar is to be manufactured, such a change can be implemented particularly flexibly and quickly, since the control unit only needs to adjust the control of at least one adjustment device accordingly. No further adjustments are necessary. Furthermore, compared to known devices, significantly greater variability in setting the density profiles is possible, as any density profile can be generated within the physical limits.

A further advantage is that the density profile can be changed and/or adjusted without replacing the trimming elements of the trimming unit. This eliminates the need to provide a large number of trimming elements, significantly reducing the overall cost of these elements. It is therefore conceivable that a variety of different density profiles for different products, particularly different cigarettes, can be generated using the same trimming unit with at least one trimming element. This offers the advantage of producing both asymmetrical and symmetrical density profiles. Furthermore, it eliminates the need for time-consuming and costly retooling, thus reducing production costs and increasing the production volume per unit of time.

Another advantage is that the at least one trimming element does not need to have any depressions or protrusions, as these are not necessary for creating the desired density profiles. Therefore, the at least one trimming element can be manufactured much more simply and thus more cost-effectively.

Another advantage is that the desired density profile can be generated particularly reliably and with few errors, since the periodic change in distance results in no or significantly fewer errors in the creation of the desired density profiles.

The device for producing a strand for the tobacco processing industry, in particular a tobacco strand, is preferably a stranding machine for the tobacco processing industry, in particular a tobacco stranding machine for production a strand of tobacco, and preferably for the manufacture of cigarettes. The material is preferably tobacco.

In this document, the statements refer to a single strand or a device for producing a strand. The device can, of course, also be configured to produce multiple strands, particularly two strands. All statements therefore also apply accordingly to devices in which multiple strands, particularly two strands, are produced. In such cases, periodic changes in the distance between the trimming element and the lower strand can be made, especially on such multiple strands, to generate desired density profiles.

The conveyor belt can be described in particular as a suction belt. The conveyor belt is preferably perforated and, in particular, air-permeable, so that when the conveyor belt is subjected to negative pressure or suction air on its upper surface, material located on the underside of the conveyor belt can be drawn onto the conveyor belt and held there. The conveyor belt is preferably designed as an endless circulating conveyor belt. The conveyor belt is preferably arranged such that it moves, at least section by section, through a guide channel with lateral channel walls, thereby defining, in particular, a cross-section for the conveyed material.

The suction device is preferably designed to apply a vacuum to at least one section of the lower run of the conveyor belt to draw in the suspended material. In this way, the material can be drawn onto the conveyor belt and conveyed suspended from the lower run. The material conveyed suspended by the lower run of the conveyor belt is preferably first deposited onto a deposited section of the lower run in a deposited area and then conveyed suspended along the lower run. The conveyed material is preferably conveyed suspended from the underside of the lower run. The material deposited onto the lower run can, in the case of tobacco, be referred to as tobacco cake. The lower run of the conveyor belt preferably refers to the lower branch of the conveyor belt.

The trimming device can also be referred to as an equalizer or simply a trimmer. The trimming device comprises at least one trimming element for trimming the suspended material. This at least one trimming element is preferably designed as at least one trimmer disc. Preferably, the trimming device has several, in particular two, trimming elements, the trimming elements being preferably designed as trimmer discs.

The device preferably comprises a suction belt conveyor, wherein the suction belt conveyor includes the conveyor belt, the suction device, and the trimming device, as well as preferably at least one adjustment device. The suction belt conveyor is preferably arranged adjacent to and upstream of a formatting device of the device with respect to the material conveying direction.

The at least one adjusting device is preferably designed and arranged to adjust the distance between the at least one trimming element of the trimming device and the lower run of the conveyor belt. For this purpose, the at least one adjusting device is preferably connected to and/or in contact with the lower run of the conveyor belt.

The terms "adjusting" and "changing" the distance are used synonymously in this document. Accordingly, both "adjusting" and "changing" preferably refer to a change in the distance between the at least one trimming element of the trimming device and the lower run of the conveyor belt, effected by means of the at least one adjusting device.

Preferably, the distance between the at least one trimming element of the trimming device and the lower run of the conveyor belt is adjusted by means of the at least one adjusting device, which moves the at least one trimming element of the trimming device and the lower run of the conveyor belt relative to each other. The at least one adjusting device may also comprise several adjusting devices.

The distance between the at least one trimming element of the trimming device and the lower run of the conveyor belt is in particular a direct distance, especially the shortest distance, between the at least one trimming element and the lower run. of the conveyor belt. In particular, this distance is understood to be the distance between the side of the lower run facing the at least one trimming element and the side of the at least one trimming element facing the lower run. The distance preferably extends in a direction orthogonal to a plane in which the lower run extends above the trimming device. The distance preferably corresponds to a so-called trimming height to which the suspended material is trimmed by means of the trimming device, the trimming height changing periodically due to the change in distance. The distance is preferably adjusted such that the lower run of the conveyor belt and the at least one trimming element of the trimming device are alternately moved towards and away from each other.

The control unit is preferably coupled to the at least one adjustment device via a signal connection, preferably a wired control line, to transmit control signals from the control unit to the at least one adjustment device and to control the at least one adjustment device using these control signals. The control unit and the at least one adjustment device can be designed as separate components or integrally, in particular as a single component. The control unit is designed to control the at least one adjustment device during the strand production state of the device. The strand production state is understood to be, in particular, an operating state of the device during which a strand is produced. During the strand production state, the material is conveyed suspended from the lower run of the conveyor belt and trimmed by means of the trimming device.

The control of the at least one adjusting device is such that the distance between the at least one trimming element of the trimming device and the lower run of the conveyor belt is periodically changed. Thus, this distance changes periodically over time, i.e., a periodic distance change occurs. Preferably, the distance is continuously and repeatedly changed over time by the control unit based on a predefined periodic change. In other words, the control unit controls the at least one adjusting device such that it causes a change in the distance in a specific, recurring pattern over time. The periodic distance change can also be superimposed with another distance change, for example, a vibration, or with several distance changes. The distance change can also have a periodic component, in particular where there may be a superposition of different distance changes and then at least one component of the superimposed distance changes is periodic.

Preferably, a periodic change in the distance between the at least one trimming element and the lower run of the conveyor belt is achieved by means of the at least one adjustment device. This periodic change in distance is preferably specified by the control unit. The periodic change in distance is preferably a change in distance according to a periodic function. The change in distance preferably occurs according to a defined movement specification by the control unit. The change in distance therefore preferably occurs in a periodic manner according to the specifications previously defined by the control unit. The control unit is preferably programmable by a user, so that a desired density profile can be entered into the control unit by a user.

According to a particularly preferred embodiment, the device comprises at least one sensor designed and arranged to detect at least one property, in particular a property characterizing the density, of the material conveyed hanging from the lower run of the conveyor belt. Preferably, the at least one sensor is arranged downstream of the trimming device with respect to the material conveying direction.

Preferably, the control unit is coupled to the at least one sensor via a signal connection, and the control unit is configured to control the at least one adjustment device based on measurement signals generated by the at least one sensor, which preferably describe a density profile of the material. The at least one sensor can also comprise several sensors, in particular several sensors arranged downstream of the trimming device with respect to the material conveying direction.

Preferably, the at least one sensor is configured to detect at least one property, in particular a property characterizing the density, of the lower run of the conveyor belt and the material conveyed suspended from it. Preferably, at least one measurement is performed on the lower run of the conveyor belt only, without suspended material, in order to obtain measurement results only for the lower run. to determine the properties of the conveyor belt. Preferably, after determining at least one property, in particular a property characterizing density, of the lower run of the conveyor belt and the material suspended from it, the measurement results determined for the lower run alone are subtracted from the combined measurement of the lower run and the material in order to determine one property, in particular a property characterizing density, only for the suspended material. Thus, the influence of the lower run on the measurement can be factored out in a particularly advantageous way, and the property of the material can be determined.

A property characterizing the density can in particular be: the density of the material and/or a density profile of the material, preferably the density of the material over time and/or the density of the material over distance, and/or the weight of the material, in particular per unit length, and/or a weight profile of the material, preferably the weight of the material over time, and/or the fiber fill level of the material.

Preferably, the measurements generated by the at least one sensor are averaged to obtain a density profile of the material averaged over several measurements. Such an averaged density profile allows for conclusions to be drawn about the average density profile generated. This averaging of measurements offers the advantage of compensating for measurement inaccuracies, deviations, and the like, enabling the analysis and further processing of a relatively accurate average density profile. A weight profile can also be used instead of a density profile, particularly since the weight profile essentially corresponds to the density profile.

One advantage of such a sensor, which is coupled to the control unit via a signal connection, is that the density profile of the material can be controlled during the production of a strand. This allows the control of the at least one adjustment device to be adapted, particularly automatically, if the density profile recorded by the sensor (i.e., the actual density profile) deviates from the desired (i.e., predetermined) density profile, which is to be achieved by means of the periodic change in distance. This is achieved through a control loop. The measured, and preferably averaged, density profile can be continuously analyzed and compared with the specified, desired density profile. If deviations exist or exceed a certain predefined limit, the control of the at least one adjustment device can be adjusted so that the actual density profile again corresponds to the desired density profile or is again within a specified tolerance range.

Such a control system can advantageously avoid or at least significantly reduce undesirable deviations from the desired density profile. In particular, very uniform density profiles, and especially consistent head reinforcements, can be achieved over extended periods, even if process parameters such as material moisture, material temperature, or others change during this time.

It is particularly preferred that the at least one adjusting device is designed to change the distance between the at least one trimming element of the trimming device and the lower run of the conveyor belt by moving at least one section of the lower run of the conveyor belt relative to the at least one trimming element of the trimming device and/or by moving the at least one trimming element of the trimming device relative to the lower run of the conveyor belt.

Preferably, the distance is changed by moving the lower run of the conveyor belt relative to the at least one trimming element of the trimming device. While it is also possible for the at least one trimming element of the trimming device to be movable relative to the lower run of the conveyor belt, moving the lower run is significantly faster than moving the at least one trimming element. This allows the desired density profiles to be achieved particularly advantageously, even at very high material conveying speeds. However, it is also conceivable that both the lower run and the at least one trimming element are movable relative to each other.

It is particularly preferred that the at least one adjusting device has a control shoe which rests against the lower run of the conveyor belt, in particular against the upper side of the lower run of the conveyor belt, and wherein the at least one The adjusting device is designed to adjust the distance between the at least one trimming element of the trimming device and the lower run of the conveyor belt by moving the control shoe, preferably in such a way that the lower run of the conveyor belt is moved by means of the movement of the control shoe.

By moving the control shoe in this way, a local movement of the lower run can be achieved, in particular, with the lower run being moved within the area of the control shoe. Preferably, the control shoe is movable by means of an eccentric element arranged on a servo axis, particularly in the direction of the at least one trimming element of the trimming device, for example, vertically up and down. The lower run of the conveyor belt preferably slides along the control shoe. The upper side of the lower run is understood to be, in particular, the side of the lower run that does not point towards the trimming device, but preferably towards the suction device. Preferably, the control shoe can be moved up and down in a direction orthogonal to the material conveying direction and/or orthogonal to the plane of the lower run of the conveyor belt, for example, in a vertical direction. By moving the control shoe, the lower run of the conveyor belt can preferably be moved periodically in such a way that the periodic change in the distance between the at least one trimming element of the trimming device and the lower run of the conveyor belt is achieved.

Preferably, the lower run of the conveyor belt can be periodically adjusted in height by means of a periodic control of the control shoe. This advantageously achieves that the lower run of the conveyor belt is alternately deflected upwards and downwards, resulting in varying weight and density of the subsequently produced strand, and therefore a strand with a specific density profile. When the lower run is deflected upwards, i.e., away from the at least one trimming element, less tobacco is removed by the at least one trimming element, so that the density of the strand section produced from this material increases at that point. When it is deflected downwards, i.e., towards the at least one trimming element, more tobacco is removed by the at least one trimming element, so that the density of the strand section produced from this material decreases at that point.

It is particularly preferred that the at least one trimming element of the trimming device has a surface facing the lower run of the conveyor belt that is substantially smooth. A substantially smooth surface is understood to be, in particular, a surface that has no recesses, depressions, or protrusions. It is particularly preferred that the at least one trimming element of the trimming device has a surface facing the lower run of the conveyor belt that is free of depressions or protrusions for creating a density profile in the material strand. It is particularly preferred that the at least one trimming element of the trimming device has a surface facing the lower run of the conveyor belt that is rotationally symmetrical. The surface of the at least one trimming element of the trimming device facing the lower run of the conveyor belt is understood to be, in particular, the surface of the at least one trimming element of the trimming device that faces the lower run of the conveyor belt.

By using a substantially smooth surface on the at least one trimming element, a particularly precise cut of the suspended material can be advantageously achieved. This further reduces deviations from the desired density profile. An additional advantage of a surface design of the at least one trimming element that is free of protrusions and depressions is that the at least one trimming element can be manufactured more cost-effectively.

Preferably, the surface facing the lower run of the conveyor belt is rotationally symmetrical with respect to an axis of rotation of the at least one trimming element. An advantage of a rotationally symmetrical design is that the at least one trimming element can be manufactured particularly cost-effectively.

As an alternative to a trimming element with a smooth surface and/or a surface free of depressions and protrusions, the at least one trimming element can also have depressions and/or protrusions on the surface facing the lower run of the conveyor belt. In such an embodiment, the density profile in the strand can be generated by the change in spacing effected by the at least one adjusting device and by the depressions and/or protrusions of the at least one trimming element in combination. Particularly large density changes in the strand can be achieved in such an embodiment. This can be achieved. However, such an embodiment can also be advantageous, for example, if the aim is to move the control shoe over shorter distances, particularly at very high manufacturing speeds, especially to reduce unwanted heat generation and wear.

Preferably, each of the trimming elements of the trimming device has a surface facing towards the lower run of the conveyor belt, which is essentially smooth and/or free of depressions or protrusions to create a density profile in the material strand and/or is rotationally symmetrical.

It is particularly preferred that the periodic change in the distance between the at least one trimming element of the trimming device and the lower run of the conveyor belt is dependent on the speed at which the suspended material is conveyed along the lower run of the conveyor belt. Preferably, the period of the periodic distance change is adapted to the speed at which the suspended material is conveyed along the lower run of the conveyor belt. In particular, the period of the periodic distance change can be adapted to a duration during which the suspended material is conveyed a certain distance along the lower run of the conveyor belt.

Preferably, the periodic change in distance occurs depending on the machine cycle of the device and/or synchronously with the machine cycle of the device. This makes it particularly advantageous to ensure that areas of increased density are reliably arranged at the intended positions, namely at the head ends for head reinforcement.

It is particularly preferred that the device comprises a formatting device which is arranged downstream of the lower run of the conveyor belt with respect to the material conveying direction, wherein the formatting device is designed and arranged to wrap the material with a wrapping material, in particular cigarette paper, and to form it into a strand wrapped with wrapping material with a round or oval cross-section.

The formatting device preferably comprises a formatting belt, wherein the formatting belt is preferably designed to hold the strand together with a wrapping material. to move through the formatting device, whereby the wrapping material is folded around the strand in the formatting device.

Preferably, the periodic change in the distance between the at least one trimming element of the trimming device and the lower run of the conveyor belt is dependent on the speed at which the strand wrapped with covering material is conveyed along the formatting device.

Preferably, the conveying speed of the conveyor belt and the conveying speed of the formatting belt are different. The conveying speed of the conveyor belt is preferably higher, for example 2% higher, than the conveying speed of the formatting belt. By means of such a difference in conveying speeds, it can be achieved particularly advantageously that the strand wrapped by the formatting device is packed relatively densely and has essentially no gaps in the material.

Preferably, the density profile and/or weight profile of the strand shifts and/or changes during the transfer of the strand from the conveyor belt to the format belt.

Preferably, the device is designed such that the material conveyed hanging from the lower run has an asymmetrical density profile, and the density profile of the strand enclosed by the format belt is symmetrical or nearly symmetrical due to the transition between the lower run and the format belt. In this way, a smokable product with a symmetrical density profile can be produced with particular advantage.

It is particularly preferred that the periodic change in the distance between the at least one trimming element of the trimming device and the lower run of the conveyor belt has a period corresponding to a time duration during which the material is moved along the lower run of the conveyor belt with a smoking article stick length, in particular a tobacco stick length, or with a multiple, in particular a double, of a smoking article stick length, in particular a tobacco stick length.

The period, which can also be referred to as the period duration, is preferably adapted such that the length of the smoking article later produced from the strand, in particular in the form of a cigarette, has the desired density profile.

A stick length, or in particular a tobacco stick length, is understood to be a length corresponding to the length of a section cut from the strand for the product to be manufactured from it. Such a stick length therefore corresponds in particular to the length of the material stick, especially the tobacco stick, i.e., the length of the material, especially the tobacco, in the final product. The stick length extends in particular from the free end, the so-called base end, to the other end, the so-called filter end, which preferably rests against a filter. The density profile can, for example, be designed such that the material in the area of the free end is cut to a height of 2.5 mm to 3.5 mm along a section of approximately 18 mm to 22 mm, and the material in the area of the other end is cut to a height of 1.5 mm to 2.5 mm along a section of approximately 12 mm to 16 mm. However, it is also possible to design the density profile symmetrically with respect to the center of the material stock, especially the tobacco stock.

It is particularly preferred that the periodic change in the distance between the at least one trimming element of the trimming device and the lower run of the conveyor belt has a period of at most 1 second, preferably at most 0.5 seconds, particularly preferably at most 0.1 seconds, in particular at most 0.05 seconds, and/or at least 0.001 seconds, particularly preferably at least 0.002 seconds, in particular at least 0.005 seconds.

It is particularly preferred that the periodic change in the distance between the at least one trimming element of the trimming device and the lower run of the conveyor belt is designed in the form of a symmetrical, preferably sinusoidal, oscillation. An advantage of such a symmetrical oscillation is that it allows for the creation of a symmetrical density profile. Creating a symmetrical density profile can be particularly advantageous when both The sides of the smoking article stick, especially the tobacco stick, should have the same density.

It is particularly preferred that the periodic change in the distance between the at least one trimming element of the trimming device and the lower run of the conveyor belt has a change in distance per period of at least 0.1 mm, preferably at least 0.25 mm, and particularly preferably at least 0.5 mm. The distance between the at least one trimming element of the trimming device and the lower run of the conveyor belt is preferably changed within one period by at least 0.1 mm, preferably at least 0.25 mm, and particularly preferably at least 0.5 mm. The distance between the at least one trimming element of the trimming device and the lower run of the conveyor belt is particularly preferably changed in a range of 1 mm to 2 mm per period. It is particularly preferred that the periodic change in the distance between the at least one trimming element of the trimming device and the lower run of the conveyor belt has a change in distance per period of at most 10 mm, particularly preferably at most 5 mm, and more preferably at most 2.5 mm.

It is particularly preferred that the at least one sensor is configured as an electromagnetic measuring unit, in particular as a microwave measuring unit, and more preferably with at least one resonator cavity and/or in a U-shape. The at least one sensor is preferably configured to detect a property characterizing the density, in particular the density of the material and/or a density profile of the material, preferably the density of the material over time and/or the density of the material over distance, and/or the weight of the material, in particular per unit length, and/or the fiber fill level of the material.

It is particularly preferred that the at least one sensor is integrated into the channel walls of a downwardly open strand guide channel through which the lower run of the conveyor belt passes. The at least one sensor can be designed as a component integrated into or connected to the suction belt conveyor and/or a component of the suction belt conveyor. Alternatively, the at least one sensor can also be designed as a separate component.

It is particularly preferred that the at least one sensor comprises a format setting sensor configured and arranged to detect at least one property, in particular a property characterizing the density, of the material enclosed by the encasing material. Such a format setting sensor is preferably arranged in the format device. Such a format setting sensor is preferably arranged and configured to measure the material through the encasing material.

It is particularly preferred that the device includes a further sensor, which is designed and arranged to detect at least one property, in particular a density-characterizing property, of the material conveyed suspended from the lower run of the conveyor belt, wherein the further sensor is arranged upstream of the trimming device with respect to the material conveying direction. This further sensor is therefore preferably arranged at a position where the material conveyed suspended from the lower run of the conveyor belt has not yet been trimmed by the trimming device, i.e., where the suspended material has not yet been brought to a desired height. This further sensor is preferably designed as an electromagnetic measuring unit, in particular as a microwave measuring unit. The further sensor is preferably designed to detect a density-characterizing property, in particular the density and/or a density profile, preferably the density over time and/or the density over distance, and/or the weight per unit length and/or the fiber fill level of the suspended material. The additional sensor can be designed as a component integrated into or connected to the suction belt conveyor and/or a component of the suction belt conveyor. Alternatively, the additional sensor can also be designed as a separate component. In particular, the additional sensor is a sensor different from the at least one sensor.

One advantage of such an additional sensor is that unwanted weight fluctuations can be significantly reduced, as material properties can be detected by the additional sensor even before the material is trimmed. By detecting the properties of the suspended material before trimming, i.e., before the material is trimmed, the strand production process can be adjusted directly during operation according to the detected properties. This allows for... In particular, it makes it possible to control the trimming device and/or the conveyor belt depending on the properties detected by the additional sensor in such a way that the material is trimmed so that the weight distribution becomes more uniform and the produced strand has significantly lower weight fluctuations.

Preferably, the additional sensor is configured to detect gaps in the material, and the control unit is configured to control, based on the gaps detected by the first sensor, the at least one adjustment device for adjusting the distance between the at least one trimming element of the trimming device and the lower run of the conveyor belt. A particular advantage of this is that gaps in the material can be detected before the material reaches the trimming device. Thus, the trimming device and/or the conveyor belt can be adjusted based on the detected properties in such a way that the detected gaps in the material are compensated for by adjusting or controlling the trimming height. This also results in a beneficial reduction in weight fluctuations.

Preferably, the control unit is coupled to the further sensor via a signal connection, wherein the control unit is preferably designed to control, depending on measurement signals generated by the further sensor, which preferably describe a density profile of the material, the at least one adjusting device for adjusting the distance between the at least one trimming element of the trimming device and the lower run of the conveyor belt in such a way that a distance change superimposed on the periodic distance change, in particular a non-periodic, occurs.

Preferably, the distance is changed by means of the at least one adjustment device as a result of the further sensor, as a distance change superimposed on the periodic distance change. Accordingly, the periodic distance change is particularly pronounced, wherein a further distance change superimposed on this periodic distance change occurs depending on measurement signals generated by the further sensor.

According to another aspect, the aforementioned task is solved by a process for producing a strand of tobacco processing material, in particular of a tobacco strand, the method comprising the steps: conveying material, in particular tobacco, by means of a conveyor belt having a lower run, wherein the material is conveyed hanging on the lower run of the conveyor belt along a material conveying direction, suction of the suspended conveyed material by means of a suction device, wherein the suction device applies a vacuum to at least one section of the lower run of the conveyor belt to draw the suspended conveyed material onto the lower run of the conveyor belt, and trimming of the material suspended on the lower run of the conveyor belt by means of a trimming device with at least one trimming element.

According to the invention, the method comprises the following step: adjusting a distance between the at least one trimming element of the trimming device and the lower run of the conveyor belt by means of at least one adjusting device during a strand production state of the device in such a way that the distance between the at least one trimming element of the trimming device and the lower run of the conveyor belt is changed periodically over time or is changed with a periodic component over time.

It is particularly preferred that the adjustment of the distance between the at least one trimming element of the trimming device and the lower run of the conveyor belt is carried out by means of the at least one adjusting device in such a way that the distance between the at least one trimming element of the trimming device and the lower run of the conveyor belt is changed periodically over time according to a predetermined periodic distance change or is changed with a periodic component over time.

It is particularly preferred that the periodic change in distance is specified by a control unit configured to control the at least one adjustment device during the strand manufacturing phase of the device. The control unit preferably transmits control signals to the at least one adjustment device, particularly preferably via a control line connected to both the control unit and the at least one adjustment device.

It is particularly preferred that the method comprises: detecting a density profile of the material conveyed along the material conveying direction by means of at least one sensor, wherein preferably the at least one sensor is arranged downstream of the trimming device with respect to the material conveying direction.

It is particularly preferred that the method comprises: determining an average density profile from several, preferably at least 10, particularly preferably at least 50, and especially at least 100, recorded density profiles. Instead of an average density profile, an average weight profile can also be determined. The descriptions regarding the density profile then apply accordingly to the weight profile.

Preferably, several density profiles are recorded sequentially, and an average density profile is created from these profiles. Preferably, this is done by averaging. Such averaging allows measurement inaccuracies and the like to be compensated for.

It is particularly preferred that the method comprises: controlling the adjustment of the distance between the at least one trimming element of the trimming device and the lower run of the conveyor belt as a function of the determined average density profile of the material. The control is preferably carried out by means of the control unit, which is coupled to the at least one sensor via a signal connection.

Preferably, the method further comprises: displaying the determined average density profile of the material and a density profile specified by the control unit in a superimposed representation using a display device. Preferably, the averaged density profile and the density profile specified by the control unit are displayed on a display device of the apparatus, with the averaged density profile and the specified density profile being displayed superimposed. This allows it to be directly and advantageously recognized whether, and if so, to what extent, the determined average density profile deviates from the specified density profile.

It is particularly preferred that the method comprises: performing a calibration, whereby it is determined how the mean density profile of the material conveyed suspended from the lower run of the conveyor belt is affected by a predetermined periodic adjustment of the The distance between the at least one trimming element of the trimming device and the lower run of the conveyor belt depends on this.

Preferably, a system response is determined. Specifically, it is determined which density profile is generated with which control parameters. By taking the system response into account, the desired density profile can be achieved in a particularly advantageous way, since the control parameters can then be adjusted accordingly.

It is particularly preferred that the method comprises: providing a device as described herein, wherein the steps of the method are preferably carried out using the device.

According to a further aspect, the aforementioned problem is solved by a smokable article, in particular in the form of a cigarette, preferably in the form of a filter cigarette, wherein the smokable article comprises a rod-shaped tobacco section extending along an article central axis from a first head end, which is particularly designed as a filter end, to a second head end, which is particularly designed as a burning end, and having a tobacco stem length, wherein a tobacco section center point is arranged centrally between the first head end and the second head end on the article central axis, wherein the rod-shaped tobacco section comprises tobacco and a wrapping material, in particular wrapping paper, arranged circumferentially around the tobacco, and wherein the tobacco of the tobacco section has a density distribution with a density of the tobacco that changes along the article central axis, wherein the density distribution of the tobacco from the first head end of the tobacco section to the second head end of the tobacco section along the article central axis with respect to the tobacco section center point is symmetrical or asymmetrical, and the density of the tobacco at the first head end of the tobacco section and/or is at its maximum at the second end of the tobacco section and/or the density of the tobacco is at its minimum at the center of the tobacco section and/or at the first end of the tobacco section,

The rod-shaped tobacco section can also be called the tobacco stick. The second end of the head, in particular the burning end, can also be called the free head end. Preferably, the smokable article includes a rod-shaped filter which extends along the central axis of the article and is connected to the first end of the rod-shaped tobacco section.

Preferably, the smokable article is obtainable by a method as described herein. Preferably, the apparatus described herein is configured for the production of such a smokable article. Therefore, the use of the apparatus described herein for the production of such a smokable article is particularly preferred.

Preferably, the tobacco in the tobacco section has a density distribution in the form of a period of a cosine function (cos(0) to cos( 2π )), where the density and/or weight of the material is indicated on the y-axis. Preferably, the density of the tobacco is highest at the first and second ends of the tobacco section. Preferably, the density of the tobacco is lowest at the center of the tobacco section.

One advantage of such a smoking product is that it features good head reinforcement at both the first and second heads. This effectively prevents tobacco from falling out of either head at any point during or after production. Another advantage is the highly efficient use of tobacco. This efficient use means less tobacco is needed for each smoking product, thus reducing manufacturing costs. Conventional smoking products, on the other hand, do not have a symmetrical density profile, but rather an asymmetrical one.

According to a further aspect, the aforementioned problem is solved by an arrangement comprising several, preferably at least ten, and particularly preferably at least twenty, smokable articles as described herein, arranged in a package, wherein the average mass deviation of the smokable articles is less than 3% by weight, particularly less than 2% by weight, and more preferably less than 1% by weight. The package is preferably designed as a box. A mass deviation is preferably understood to be a deviation of the mass of a smokable article divided by the average mass of all smokable articles arranged in the package. The average mass deviation is, in particular, the Average mass deviation, taking into account all smokable articles arranged in the packaging. Preferably, the average mass deviation of the smokable articles is less than 15 mg, more preferably less than 10 mg, and particularly less than 5 mg.

One advantage of such an arrangement is a particularly low average mass deviation, which is smaller than that of known arrangements. This allows for a particularly high and reliably consistent product quality.

Preferably, the smokable articles are arranged side by side within the packaging in such a way that the central axes of the smokable articles are arranged parallel to each other.

For the advantages, design variants and design details of the various aspects of the solutions described here and their respective possible further developments, reference is also made to the description of the corresponding features, details and advantages of the other aspects and their further developments.

Fig. 1:

eine schematische Darstellung eines Ausschnitts einer Vorrichtung in einer ersten Ausführungsform zur Herstellung eines Strangs;

Fig. 2:

eine schematische Darstellung eines Ausschnitts einer Vorrichtung in einer zweiten Ausführungsform zur Herstellung eines Strangs;

Fig. 3:

eine schematische Darstellung eines Ausschnitts einer Vorrichtung in einer dritten Ausführungsform zur Herstellung eines Strangs;

Fig. 4a:

eine schematische Darstellung eines ersten Gewichtsprofils;

Fig. 4b:

eine schematische Darstellung eines zweiten Gewichtsprofils;

Fig. 4c:

eine schematische Darstellung eines dritten Gewichtsprofils;

Fig. 5:

eine Messkurve eines Gewichtsprofils im Vergleich zu einem vorgegebenen Gewichtsprofil, angezeigt mittels einer Anzeigeeinrichtung;

Fig. 6:

eine schematische Darstellung einer vierten Ausführungsform einer Vorrichtung zur Herstellung eines Strangs;

Fig. 7:

eine schematische Darstellung einer fünften Ausführungsform einer Vorrichtung zur Herstellung eines Strangs;

Fig. 8:

eine schematische Darstellung einer sechsten Ausführungsform einer Vorrichtung zur Herstellung eines Strangs;

Fig. 9:

eine schematische Darstellung einer siebten Ausführungsform einer Vorrichtung zur Herstellung eines Strangs;

Fig. 10:

eine schematische Darstellung einer Vorrichtung zur Herstellung eines Strangs der tabakverarbeitenden Industrie;

Fig. 11:

eine schematische Darstellung eines rauchbaren Artikels und eines Dichteprofils des rauchbaren Artikels;

Fig. 12a:

eine schematische Darstellung eines Verfahrens zur Herstellung eines Strangs der tabakverarbeitenden Industrie;

Fig. 12b:

eine schematische Darstellung eines Verfahrens zur Herstellung eines Strangs der tabakverarbeitenden Industrie.

Preferred embodiments are explained by way of example with reference to the accompanying figures. The drawings are not necessarily to scale. In the figures, identical or essentially functionally equivalent or similar elements are designated with the same reference numerals. They show:

Fig. 1:

a schematic representation of a section of a device in a first embodiment for the production of a strand;

Fig. 2:

a schematic representation of a section of a device in a second embodiment for the production of a strand;

Fig. 3:

a schematic representation of a section of a device in a third embodiment for the production of a strand;

Fig. 4a:

a schematic representation of a first weight profile;

Fig. 4b:

a schematic representation of a second weight profile;

Fig. 4c:

a schematic representation of a third weight profile;

Fig. 5:

a measurement curve of a weight profile compared to a predefined weight profile, displayed by means of a display device;

Fig. 6:

a schematic representation of a fourth embodiment of a device for producing a strand;

Fig. 7:

a schematic representation of a fifth embodiment of a device for producing a strand;

Fig. 8:

a schematic representation of a sixth embodiment of a device for producing a strand;

Fig. 9:

a schematic representation of a seventh embodiment of a device for producing a strand;

Fig. 10:

a schematic representation of a device for the production of a strand of tobacco processing material;

Fig. 11:

a schematic representation of a smokable article and a density profile of the smokable article;

Fig. 12a:

a schematic representation of a process for the production of a strand of tobacco processing material;

Fig. 12b:

a schematic representation of a process for the production of a strand of tobacco in the tobacco processing industry.

Fig. 1 Figure 1 shows a schematic representation of a section of a device in a first embodiment for producing a strand for the tobacco processing industry, in particular a tobacco strand, from a material M. The material M1 has been shrunk onto the lower run 17a of a conveyor belt in the area shown on the right. The height and weight of the material M1, and thus also its density, are not constant along the x-direction, as schematically shown on the right. The material M1 is conveyed suspended along the material conveying direction F by means of the lower run 17a, which is part of a conveyor belt. The material M1 then encounters a trimming device 19, which has the trimming element 19a. Above the trimming element 19a, a control shoe 80, designed as a sliding shoe, is provided, which is in contact with the lower run 17a. A distance A is present between the lower run 17a and the trimming element 19a of the trimming device. The distance A is the distance between the underside of the lower run 17a and the upper side 19c of the trimming element 19a. Using the trimming element 19a, the material M1 is essentially trimmed to a height corresponding to distance A and then conveyed at this height along the material conveying direction F as material M2, suspended along the lower run 17a. However, the height, or distance A, is not constant. The height is periodically adjusted over time by means of a movement of the control shoe 80. The material M2 then exhibits a density fluctuation after trimming due to the periodic change in distance, compared to the one in Fig. 1 The schematically shown sinusoidal profile M2 is used. The control shoe 80 is moved periodically in the vertical direction h, as can be seen in the diagram h over x. This movement of the control shoe 80 causes the lower run 17a below the control shoe 80 to move along with it. As a result, with the trimming element 19a stationary, the distance A is periodically changed according to the movement of the control shoe 80 in the vertical direction h. A movement of the control shoe 80 in the direction h causes a corresponding change in the density of the trimmed material M2. A control unit 60 and an adjusting device 71 are provided for controlling and executing the change in distance. The control shoe 80 is a component of the adjusting device 71. The adjusting device 71 is designed to adjust the distance A between the trimming element 19a of the trimming device 19 and the lower run 17a of the conveyor belt. The control unit 60 is designed to control the adjusting device 71 during a strand production phase of the device such that the adjusting device 71 periodically changes the distance A between the trimming element 19a and the lower run 17a of the conveyor belt over time. The control unit 60 is signal-coupled to the adjusting device 71 via the signal line 60b. This periodic change in distance generates a periodic weight profile (G versus x) of the material and a periodic density profile (D versus x) of the material, both corresponding to the change in distance. These two diagrams illustrate a section from a first end K1 to a second end, which is designed as the firing end B, and further to another first end K2.

Fig. 2 Figure 1 shows a schematic representation of a section of a device in a second embodiment for producing a strand. The figure in Fig. 2 The setup shown corresponds to the one described in connection with Fig. 1 described structure. In Fig. 2 However, an additional sensor 20 is now provided. The sensor 20 is designed and positioned to detect a density-characteristic property of the material M conveyed hanging from the lower run 17a of the conveyor belt. The sensor 20 is arranged downstream of the trimming device 19 with respect to the material conveying direction F. The density-characteristic property is therefore detected after trimming by the trimming device 19. The control unit 60 is coupled to the sensor 20 via a signal connection. The control unit 60 is designed to... The adjusting device 71 is controlled by means of measurement signals generated by the sensor 20, which describe a density profile of the material M, M2.

Fig. 3 Figure 1 shows a schematic representation of a section of a device in a third embodiment for producing a strand. The figure in Fig. 3 The setup shown corresponds to the one described in connection with Fig. 2 described structure. In Fig. 3 However, in addition to the first adjusting device 71, a second adjusting device 72 is now provided. The second adjusting device 72 is designed and arranged to change the distance A between the trimming element 19a of the trimming device 19 and the lower run 17a of the conveyor belt by moving at least one trimming element 19a of the trimming device relative to the lower run 17a of the conveyor belt. In this case, Fig. 3 In the illustrated embodiment, the lower run 17a can thus be moved by means of the first adjusting device 71, thereby changing the distance A. Alternatively, the trimming element 19a can also be moved by means of the second adjusting device 72, thereby changing the distance A. The control unit 60 is signal-connected to the second adjusting device 72 via the signal line 60c.

Fig. 4a Figure 1 shows a schematic representation of the first weight profile of a strand section with twice the working length. The first end, K1 and K2, is the filter end for a cigarette made from this strand section. The second end, which will later become the burning end, is shown in the middle. A weight profile (G versus x) is shown here; a density profile of this section would look the same, i.e., have the same shape. Fig. 4a shows an asymmetric weight profile - and thus an asymmetric density profile - since the weight or density at the firing end B is greater than at the respective first head ends K1, K2. Fig. 4b Figure 1 shows a schematic representation of a second weight profile of a strand section with twice the working length. The first end, K1 and K2, is the filter end for a cigarette made from this strand section. The second end, which will later become the burning end, is shown in the middle. A weight profile (G versus x) is shown here; a density profile of this section would look the same, i.e., have the same shape. Fig. 4b This shows a symmetrical weight profile – and thus a symmetrical density profile – since the weight or density at the firing end B is the same as at the respective first head ends K1, K2. Using the device, an asymmetrical density profile, as shown in the In connection with Fig. 4a described, or a symmetrical density profile, as described in connection with Fig. 4b described, generated. Fig. 4c This shows another weight profile – and thus another density profile – in which the weight, and therefore the density, is minimal at the first head end K1, K2, and the weight or density is constant between the first head end K1, K2 and the center of the tobacco section, with the weight or density being increased only at the burning end B. Such a profile, as in Fig. 4c The weight distribution shown (and thus density distribution) can be particularly advantageous for relatively short tobacco products, such as those used in Heated Tobacco Products (HTP).

Fig. 5 Figure 64 shows a measurement curve R of a weight profile (G over L) compared to a predefined weight profile I. The measurement curve R and the predefined profile I are superimposed and displayed using a display device 64. Because the measurement curve R and the predefined profile I are superimposed, the deviations between the predefined profile I and the measurement curve R can be directly observed. As can be seen, the deviations are very small. The distance SB is varied by +/- 1 mm per period. This results in a weight stroke G-stroke of +/- 60 mg per period.

Fig. 6 Figure 1 shows a schematic representation of a fourth embodiment of a device for producing a strand. The device comprises a suction belt conveyor 15 and a control unit 60. The setup shown here essentially corresponds to the setup described in Figure 2. Fig. 2 In the embodiment shown, the distance between the trimming element 19a and the lower run 17a below the control shoe 80 is adjustable by moving the control shoe 80. The conveyor belt 17 is guided by conveyor belt rollers 17b, 17c, 17d, 17e. The lower run 17a of the conveyor belt 17 has a lofting section 17x in which the material M is lofted in the direction S. In the conveying section 17y, the material M is then conveyed suspended along the material conveying direction F. Within the conveyor belt 17, at least one section of the lower run 17a of the conveyor belt 17 is subjected to a vacuum by means of a suction device 18 to draw the suspended material M onto the lower run 17a of the conveyor belt 17. The control unit 60 is coupled to the sensor 20 via signal line 60d and furthermore to an adjusting device (not shown) for adjusting the distance between the trimming element 19a and the control shoe 80 via signal line 60b. coupled. In the embodiment shown here, the sensor 20 is U-shaped with the opening facing downwards and is integrated into the downwardly open strand guide channel 16, through which the lower run 17a of the conveyor belt 17 passes. The sensor 20 is designed as an electromagnetic measuring unit, namely as a microwave measuring unit, and is configured to detect the density or a density profile of the suspended conveyed material M2.

Fig. 7 Figure 1 shows a schematic representation of a fifth embodiment of a device for producing a strand. The suction belt conveyor 15 shown here is, as in connection with Fig. 6 described structure. In Fig. 7 A formatting device 26 is additionally shown, which is arranged downstream of the suction belt conveyor 15 and which has a format belt 24 that is guided by format belt rollers 24a, 24b. A density profile of the material M, M2 can be detected by means of the formatting device sensor 30, which is arranged in the area of the formatting device 26. Fig. 7 Further details regarding the design of a possible control system configuration are shown. The measurement signals acquired by sensors 20 and 30 are transferred to module 61 and subsequently to the measuring computer 62. It is also possible to use only one of these sensors 20 or 30. Measured values can be visualized using the display 64. Based on the received measurement signals, the measuring computer 62 transmits data to the control unit 60. The control unit 60 can then, in turn, control and, in particular, regulate an adjustment device for adjusting the distance between the at least one trimming element 19a and the lower run 17a, depending on the measured values.

Fig. 8 Figure 1 shows a schematic representation of a sixth embodiment of a device for producing a strand. The suction belt conveyor 15 shown here is essentially the same as described in connection with Fig. 6 The structure is described. However, in the Fig. 8 In the illustrated embodiment, a further sensor 10 is provided, which is arranged upstream of the trimming device 19 and is connected to the control unit 60 via a signal line 60d. The further sensor 10 is designed and arranged to detect a property characterizing the density of the material M conveyed hanging from the lower run 17a of the conveyor belt 17. The control unit 60 can then control the change in distance depending on measurement signals detected by sensor 20 and by measurement signals detected by the further sensor 10.

Fig. 9 Figure 1 shows a schematic representation of a seventh embodiment of a device for producing a strand. The structure of this embodiment essentially corresponds to the structure of the device described in connection with Fig. 7 described embodiment, however, wherein a as in connection with Fig. 8 The further sensor 10 described above is provided, which can transmit its measurement data to module 61.

Fig. 10 Figure 1 shows a schematic representation of a device 50 in the form of a cigarette strand machine for the production of a strand for the tobacco processing industry. A pre-distributor 2 is fed portion by portion from a sluice gate 1 (in Fig. 10 (not shown) tobacco fibers. A discharge roller 3 in the pre-distributor 2 supplies a storage container 4 with tobacco fibers from the pre-distributor 2. From the storage container 4, a steep conveyor 5 removes the tobacco fibers and feeds a tumbling chute 6. From the tumbling chute 6, a pin roller 7 removes a substantially uniform stream of tobacco fibers, which is knocked out of the pins of the pin roller 7 by a knockout roller 8 and flung onto a flail 9 rotating at a constant speed. On the flail 9, a tobacco fleece is formed from the tobacco stream. The tobacco fleece is flung into a classifying device 11, which essentially consists of an air curtain through which larger or heavier tobacco particles pass, while all other tobacco particles are lowered by the air into a hopper 14 formed by a pin roller 12 and a wall 13. From the pin roller 12, the tobacco fibers are conveyed from the hopper 12 to the suction belt conveyor 15, specifically into a strand guide channel 16. There, they are flung against the lower run of an air-permeable, continuously circulating conveyor belt 17, which forms the bottom of the strand guide channel 16 and is pressurized from its rear side. On this belt, the tobacco fibers are formed into a strand-like tobacco fiber cake, which is thus held in place by air drawn into a vacuum chamber 18. The circulating conveyor belt 17 conveys the formed or accumulated tobacco fiber cake as a hanging strand along the strand guide channel 16. In the illustrated embodiment, the lower run of the conveyor belt 17 extends through the strand guide channel 16 from its beginning, where the strand formation zone is located, to a trimming device 19 for removing excess tobacco fibers. The tobacco fiber strand thus formed is then placed onto a cigarette paper strip 21 guided in parallel. The cigarette paper strip 21 is unwound from a bobbin 22, guided through a printing unit 23, and placed onto a driven formatting belt 24. The formatting belt 24 transports The tobacco strand, together with the cigarette paper strip 21, passes through a formatting device 26, in which the cigarette paper strip 21 is folded around the tobacco strand so that only a narrow edge protrudes. This edge is then glued in a known manner by a gluing apparatus (not shown). The resulting glued seam is then closed and dried by a tandem seaming plate 27. The cigarette strand 28 thus formed passes through a measuring device in the form of a sensor 30 and is subsequently cut into double-length cigarettes 32 by a cutting apparatus 31. The double-length cigarettes 32 are transferred by a transfer device 34, which has controlled arms, to a receiving drum 36 of a filter-setting machine 37. On the cutting drum 38 of this machine, they are divided into individual cigarettes by a circular knife. Conveyor belts 39, 41 convey excess tobacco fibers separated by the trimming unit 19, which has two trimmer discs 19a, 19b, into a container 42 located below the storage container 4. From this container, these excess tobacco fibers are removed as recycled tobacco by the inclined conveyor 5. The sensor 30 can, for example, be configured to detect the cross-section, ovality or roundness, and/or density of the cigarette strand 28, and/or the weight of the cigarettes 32, and/or the weight of the cigarette strand 28 per unit length, and/or the fiber fill level in the cigarette strand 28 and/or in the cigarettes 32, and to generate a corresponding output signal. This output signal is transmitted to a control unit (not shown here). In addition to the sensor 30, a sensor 20 is provided, which is located downstream of the trimming unit 19. Furthermore, an additional sensor 10, arranged upstream of the trimming device 19, may be provided. The sensor 20 and/or the sensor 30, and optionally the sensor 10, and possible arrangements and embodiments of these sensors are described in particular in connection with the Figs. 1-9 described in detail.

Fig. 11 Figure 1 shows a schematic representation of a smokable article 90 in the form of a filter cigarette and a density profile (D over x) of the smokable article 90. The smokable article 90 has a rod-shaped tobacco section 91 that extends along an article central axis AM from a first head end K1, the filter end, to a second head end B, the burning end, and has a tobacco stem length TSL. A filter 94 is arranged at the filter end K1. A tobacco section center point TMP is arranged on the article central axis AM midway between the first head end K1 and the second head end B. The rod-shaped tobacco section 91 comprises tobacco 92 and a wrapping paper 93 arranged circumferentially around the tobacco. Tobacco 92 of tobacco section 91 exhibits a density distribution with a density that changes along the article's central axis AM, as shown in the diagram. The density distribution of tobacco 92 from the first head end K1 of tobacco section 91 to the second head end B of tobacco section 91 along the article's central axis AM with respect to the tobacco section's center TMP is symmetrical. The density Dmax of tobacco 92 at the first head end K1 of tobacco section 91 and the density of tobacco 92 at the second head end B of tobacco section 91 are equal and at their maximum. The density Dmin of tobacco 92 at the tobacco section's center TMP is minimum. Such smokable articles 90 can be arranged in an arrangement 99 comprising several smokable articles 90 arranged in a package 98. However, other density profiles, such as asymmetrical density profiles, are also conceivable. In particular, density profiles such as those shown in [reference missing] are also possible. Figs. 4a, 4b and 4c presented and in connection with the Figs. 4a, 4b and 4c are described as trained.

Fig. 12a Figure 300 shows a schematic representation of a process 300 for the production of a strand for the tobacco processing industry, in particular a tobacco strand. The process 300 comprises the following steps: In step 310a, conveying material M, in particular tobacco, by means of a conveyor belt 17 having a lower run 17a, wherein the material is conveyed suspended from the lower run 17a of the conveyor belt 17 along a material conveying direction F. In step 310b, suction of the suspended material M by means of a suction device 18, wherein the suction device 18 applies a vacuum to at least a section of the lower run 17a of the conveyor belt 17 to draw the suspended material M onto the lower run 17a of the conveyor belt 17. In step 320, the material M conveyed suspended from the lower run 17a of the conveyor belt 17 is trimmed by means of a trimming device 19 with at least one trimming element 19a, 19b. In step 330, a distance A between the at least one trimming element 19a, 19b of the trimming device 19 and the lower run 17a of the conveyor belt 17 is adjusted by means of at least one adjusting device 71, 72 during a strand production state of the device in such a way that the distance A between the at least one trimming element 19a, 19b of the trimming device 19 and the lower run 17a of the conveyor belt 17 is periodically changed over time. In step 340, a density profile of the material M conveyed along the material conveying direction F is detected by means of at least one sensor 20, 30, wherein preferably the at least one Sensor 20 is arranged downstream of the trimming device 19 with respect to the material conveying direction F.

Fig. 12b Figure 3 shows a schematic representation of a process 300 for the production of a strand for the tobacco processing industry, in particular a tobacco strand. The process 300 comprises the following steps: In step 305, a device as described herein is provided, wherein the steps of process 300 are preferably carried out using the device. This is followed by steps 310a, 310b, 320, 330 and 340 as described in connection with Fig. 12a described. The following steps then follow: In step 350, determining an average density profile from several, preferably at least 10, particularly preferably at least 50, and especially at least 100, recorded density profiles. In step 355, performing a calibration, whereby it is determined how the average density profile of the material conveyed suspended from the lower run 17a of the conveyor belt 17 depends on a predetermined periodic adjustment of the distance between the at least one trimming element of the trimming device and the lower run of the conveyor belt. In step 360, controlling the adjustment of the distance A between the at least one trimming element 19a, 19b of the trimming device 19 and the lower run 17a of the conveyor belt 17 as a function of the determined average density profile of the material M, M2. In step 370, the determined mean density profile of the material and a density profile specified by the control unit are displayed in a superimposed representation using a display device.

List of reference symbols

1

sluice

2

Pre-distribution

3

Removal roller

4

Storage container

5

Steep conveyor

6

Storage shaft

7

Pin roller

8

Discharge roller

9

Scatter cloth

10

additional sensor

11

Visual device

12

Pin roller

13

Wall

14

funnel

15

Suction belt conveyor

16

Strand guide channel

17

conveyor belt

17a

lower run of the conveyor belt

17b, c, d, e

Conveyor belt rollers

17x

Upstream section of the lower trum

17y

Conveying section of the lower conduit

18

Suction system

19

Trim device

19a, 19b

Trim element of the trim device

19c

Top side of the trim element of the trim device

20

sensor

21

cigarette paper strips

22

Bobbin

23

Printed matter

24

Format band

24a, b

Format tape rolls

26

Format setup

27

Tandem seam plate

28

cigarette strand

30

Format setup sensor

31

knife apparatus

32

cigarettes

34

transfer device

36

Takeover drum

37

Filter preparation machine

38

Cutting drum

39, 41

Conveyor belts

42

container

50

Device for the production of a strand for the tobacco processing industry

60

Control unit

60a, b, c, d

Signal line

61

module

62

Measuring computer

64

Display device

71, 72

Adjustment device

80

Regular shoe

90

smokable article

91

Tobacco section

92

tobacco

93

Wrapping paper

94

filter

98

Packaging

99

arrangement

300

Method for producing a strand for the tobacco processing industry

305-370

Procedural steps

A

Distance between trim element of the trim device and lower run

AM

Article center axis

B

Brandende, freie Kopfende, zweite Kopfende

K1, K2

Filter end, first head end

F

Material conveying direction

M, M1, M2

material

S

Upward direction

TMP

Tobacco section center

TSL

Tobacco stem length

Claims (15)

Device for the production of a strand for the tobacco processing industry, in particular a tobacco strand, the device comprising - a conveyor belt (17) having a lower run (17a), wherein the conveyor belt (17) is designed and arranged to convey material (M), in particular tobacco, suspended from the lower run (17a) of the conveyor belt (17) along a material conveying direction (F), - a suction device (18) for applying a vacuum to at least one section of the lower run (17a) of the conveyor belt (17) to draw the suspended conveyed material (M) onto the lower run (17a) of the conveyor belt (17), - a trimming device (19) with at least one trimming element (19a, 19b) for trimming the material (M) conveyed hanging from the lower run (17a) of the conveyor belt (17), and - at least one adjusting device (71, 72) for adjusting a distance (A) between the at least one trimming element (19a, 19b) of the trimming device (19) and the lower run (17a) of the conveyor belt (17), characterized by the fact that
the device comprises a control unit (60) configured to control the at least one adjusting device (71, 72) during a strand production state of the device such that the at least one adjusting device periodically changes the distance (A) between the at least one trimming element (19a, 19b) of the trimming device (19) and the lower run (17a) of the conveyor belt (17) over time or changes it with a periodic component over time. Device according to the preceding claim, comprising - at least one sensor (20, 30) which is designed and arranged to detect at least one property, in particular a property characterizing the density, of the material (M) conveyed hanging from the lower run (17a) of the conveyor belt (17), wherein preferably the at least one sensor (20, 30) is arranged downstream of the trimming device (19) with respect to the material conveying direction (F),
wherein the control unit (60) is coupled to the at least one sensor (20, 30) via signal technology, and wherein the control unit (60) is designed is to control the at least one adjustment device (71, 72) depending on measurement signals generated by means of the at least one sensor (20, 30), which preferably describe a density profile of the material (M, M2). Device according to at least one of the preceding claims, wherein the at least one adjusting device (71, 72) is designed and arranged to change the distance (A) between the at least one trimming element (19a, 19b) of the trimming device (19) and the lower run (17a) of the conveyor belt (17) by moving at least one section of the lower run (17a) of the conveyor belt (17) relative to the at least one trimming element (19a, 19b) of the trimming device and/or by moving the at least one trimming element (19a, 19b) of the trimming device relative to the lower run (17a) of the conveyor belt (17), and/or wherein the at least one adjusting device (71, 72) has a control shoe (80) which bears against the lower run (17a) of the conveyor belt (17), in particular against the upper side of the lower run (17a) of the conveyor belt (17), and wherein the at least one adjusting device (71, 72) is designed to adjust the distance (A) between the at least one trimming element (19a, 19b) of the trimming device (19) and the lower run (17a) of the conveyor belt (17) by moving the control shoe (80), preferably in such a way that the lower run (17a) of the conveyor belt (17) is moved by means of the movement of the control shoe (80). Device according to at least one of the preceding claims, wherein the at least one trimming element (19a, 19b) of the trimming device (19) has a surface facing towards the lower run of the conveyor belt which is essentially smooth and/or is free of depressions or protrusions for generating a density profile in the material strand and/or is rotationally symmetrical, wherein preferably each of the trimming elements (19a, 19b) of the trimming device (19) has a surface facing towards the lower run of the conveyor belt which is essentially smooth and/or is free of depressions or protrusions to create a density profile in the material strand and/or is rotationally symmetrical. Device according to at least one of the preceding claims,
wherein the periodic change of the distance (A) between the at least one trim element (19a, 19b) of the trim device (19) and the lower run (17a) of the conveyor belt (17) is carried out depending on the speed at which the material is conveyed hanging along the lower run of the conveyor belt. Device according to at least one of the preceding claims, comprising - a formatting device (26) which is arranged downstream of the lower run (17a) of the conveyor belt (17) with respect to the material conveying direction (F), wherein the formatting device (26) is designed and arranged to wrap the material (M) with a wrapping material, in particular cigarette paper, and to form it into a strand wrapped with wrapping material with a round or oval cross-section, wherein preferably the periodic change of the distance (A) between the at least one trimming element (19a, 19b) of the trimming device (19) and the lower run (17a) of the conveyor belt (17) is carried out depending on the speed at which the strand wrapped with covering material is conveyed along the formatting device (26). Device according to at least one of the preceding claims, wherein the periodic change in the distance (A) between the at least one trimming element (19a, 19b) of the trimming device (19) and the lower run (17a) of the conveyor belt (17) has a period corresponding to a time duration during which the material is moved along the lower run of the conveyor belt with a smoking article stick length, in particular a tobacco stick length, or with a multiple, in particular a double, of a smoking article stick length, in particular a tobacco stick length, and/or wherein the periodic change of the distance (A) between the at least one trimming element (19a, 19b) of the trimming device (19) and the lower run (17a) of the conveyor belt (17) has a period which is at most 1 second, preferably at most 0.5 seconds, particularly preferably at most 0.1 seconds, in particular at most 0.05 seconds, and/or which is at least 0.001 seconds, particularly preferably at least 0.002 seconds, in particular at least 0.005 seconds. Device according to at least one of the preceding claims, wherein the periodic change in the distance (A) between the at least one trimming element (19a, 19b) of the trimming device (19) and the lower run (17a) of the conveyor belt (17) is designed in the form of a symmetrical, preferably sinusoidal, oscillation and/or wherein the periodic change of the distance (A) between the at least one trimming element (19a, 19b) of the trimming device (19) and the lower run (17a) of the conveyor belt (17) has a change of distance per period of at least 0.1 mm, preferably at least 0.25 mm, particularly preferably at least 0.5 mm, and/or of at most 10 mm, particularly preferably at most 5 mm, in particular at most 2.5 mm. Device according to at least one of the preceding claims, wherein the at least one sensor (20, 30) is designed as an electromagnetic measuring unit, in particular as a microwave measuring unit, particularly preferably with at least one resonator cavity and/or in a U-shape, and/or wherein the at least one sensor (20, 30) is integrated into channel walls (100e, 100f) of a downwardly open strand guide channel (16) through which the lower run (17a) of the conveyor belt (17) passes, and/or wherein the at least one sensor (20, 30) comprises a format setup sensor (30) which is designed and arranged to detect at least one property, in particular a property characterizing the density, of the material (M) covered with encasing material. Device according to at least one of the preceding claims, comprising - a further sensor (10) which is designed and arranged to detect at least one property, in particular a property characterizing the density, of the material (M) conveyed hanging from the lower run (17a) of the conveyor belt (17), wherein the further sensor (10) is arranged upstream of the trimming device (19) with respect to the material conveying direction (F), wherein the control unit (60) is preferably coupled to the further sensor (10) via a signal connection, wherein the control unit (60) is preferably configured to adjust, depending on measurement signals generated by the further sensor (10), which preferably describe a density profile of the material (M, M1), the at least one adjusting device (71, 72) for adjusting the distance (A) between the at least one trimming element (19a, 19b) of the trimming device (19) and the to control the lower run (17a) of the conveyor belt (17) in such a way that a distance change superimposed on the periodic distance change, in particular a non-periodic distance change, takes place. Method (300) for the production of a strand for the tobacco processing industry, in particular a tobacco strand, the method comprising the steps: - Conveying (310a) of material (M), in particular tobacco, by means of a conveyor belt (17) which has a lower run (17a), wherein the material is conveyed suspended on the lower run (17a) of the conveyor belt (17) along a material conveying direction (F), - Suction (310b) of the suspended conveyed material (M) by means of a suction device (18), wherein the suction device (18) applies a vacuum to at least one section of the lower run (17a) of the conveyor belt (17) to draw the suspended conveyed material (M) onto the lower run (17a) of the conveyor belt (17), - Trimming (320) of the material (M) conveyed hanging from the lower run (17a) of the conveyor belt (17) by means of a trimming device (19) with at least one trimming element (19a, 19b),
characterized by - Adjusting (330) a distance (A) between the at least one trimming element (19a, 19b) of the trimming device (19) and the lower run (17a) of the conveyor belt (17) by means of at least one adjusting device (71, 72) during a strand production state of the device in such a way that the distance (A) between the at least one trimming element (19a, 19b) of the trimming device (19) and the lower run (17a) of the conveyor belt (17) is periodically changed over time or is changed with a periodic component over time, wherein preferably the periodic change in distance is specified by a control unit (60) which is designed to control the at least one adjusting device (71, 72) during the strand production state of the device. Method according to at least one of the preceding claims, - Detection (340) of a density profile of the material (M) conveyed along the material conveying direction (F) by means of at least one sensor (20, 30), wherein preferably the at least one sensor (20, 30) is arranged downstream of the trimming device (19) with respect to the material conveying direction (F), - Determining (350) an average density profile from several, preferably at least 10, particularly preferably at least 50, in particular at least 100, recorded density profiles, - Controlling (360) the adjustment of the distance (A) between the at least one trimming element (19a, 19b) of the trimming device (19) and the lower run (17a) of the conveyor belt (17) depending on the determined mean density profile of the material (M, M2), and - preferably displaying (370) the determined mean density profile of the material and a density profile specified by the control unit in a superimposed representation by means of a display device (64). Method according to at least one of the preceding claims, - Performing (355) a calibration, determining how the mean density profile of the material conveyed suspended from the lower run (17a) of the conveyor belt (17) depends on a predetermined periodic adjustment of the distance between the at least one trim element of the trim device and the lower run of the conveyor belt, and/or - Providing (305) a device according to one of claims 1-10, wherein preferably the steps of the method are carried out by means of the device. Smokeable article (90), in particular in the form of a cigarette, preferably in the form of a filter cigarette, wherein the smokable article comprises a rod-shaped tobacco section (91) extending along an article central axis (AM) from a first head end (K1), which is in particular designed as a filter end, to a second head end (B), which is in particular designed as a burning end (B), and having a tobacco stick length (TSL), wherein a tobacco section center point (TMP) is arranged centrally between the first head end (K1) and the second head end (B) on the article central axis (AM), wherein the rod-shaped tobacco section (91) comprises tobacco (92) and a wrapping material (93), in particular wrapping paper, arranged circumferentially around the tobacco, which encloses the tobacco, wherein the tobacco (92) of the tobacco section (91) has a density distribution with a density of tobacco that changes along the article's central axis (AM), characterized in that the density distribution of the tobacco (92) from the first head end (K1) of the tobacco section (91) to the second head end (B) of the tobacco section (91) along the article center axis (AM) with respect to the tobacco section center point (TMP) is symmetrical or asymmetrical and the density of the tobacco (92) is maximum at the first head end (K1) of the tobacco section (91) and/or at the second head end (B) of the tobacco section (91) and/or the density of the tobacco (92) is minimum at the tobacco section center point (TMP) and/or at the first head end (K1), wherein the smokable article (90) is preferably obtainable by the method according to one of claims 11-13. Arrangement (99) comprising several, preferably at least ten, smokable articles (90) arranged in a packaging (98) according to the preceding claim 14, wherein an average mass deviation of the smokable articles is less than 3 wt.%, particularly preferably less than 2 wt.%, and in particular less than 1 wt.%.