MXPA98008941A

MXPA98008941A - Method and device for applying substances to filter material.

Info

Publication number: MXPA98008941A
Application number: MXPA98008941A
Authority: MX
Inventors: Jung Thomas
Original assignee: Bat Cigarettenfab Gmbh
Priority date: 1997-10-30
Filing date: 1998-10-28
Publication date: 2002-03-14
Also published as: CN1216691A; BR9804311A; KR100335469B1; CA2249816C; HU9802498D0; HK1019187A1; JPH11239472A; EP0913100A2; DE19748072A1; HUP9802498A2; ES2210641T3; CN1112140C; HUP9802498A3; ATE255337T1; JP3037937B2; DE59810322D1; EP0913100B1; PL329434A1; EP0913100A3; CA2249816A1

Abstract

The method involves using a dispenser for micronized solids. An injector nozzle (26) pneumatically conveys the solids to a powder-chamber (34) through which the flat or fibrous filter material (32) is conveyed. The dispenser has a storage container (12) conveying discontinuously micronized solids, and has a gravimetrically operating fine-dispenser (14,16) which has a double worm for conveying the micronized solids to a pneumatically operating conveyor screw. Independent claims are also included for a device for carrying out the method.

Description

METHOD AND DEVICE FOR APPLYING SUBSTANCES TO A PE FILTER MATERIAL FIELD OF THE INVENTION The invention relates to a method and a device for applying substances to the fibers of a filter material for smoking articles.

BACKGROUND OF THE INVENTION It is known, from the German Patents Numbers DE 39, 04, 239, Cl and DE 38, 20, 089, C2, that substances are applied to the fibers of a tobacco smoke filter, these substances being more particularly polycarboxylic acids or acid salts thereof physiologically and sensorially safe, such as the esters of citric acid, tartaric acid, succinic acid, and malic acid. For this purpose, the polycarboxylic acids or the acid salts thereof, which are crystalline at ambient and processing temperatures, are applied in the form of fine particles having a particle size of less than 50 microns suspended in an organic liquid medium, and the resulting suspension is applied to the fibers (German Patent Number DE 39, 04, 239, Cl). As an alternative, the acid anhydrides of the di- or polycarboxylic acids can be dissolved in the organic solvent, and can be applied to the fibers, and when necessary, can be hydrolyzed with water (German Patent Number DE 38, 20 , 089, C2). The drawback of applying these substances to a suspension or a solvent, such as, for example, triacetin, is that, in high concentrations, this suspension becomes viscous, and then it can no longer be pumped, this being the reason why it does not High filter loads of these substances can be applied by these known methods.

OBJECTS AND ADVANTAGES OF THE INVENTION The invention is based on the object of defining a method and a device for applying substances to the fibers of a filter material for smoking articles, which obviate the aforementioned drawbacks. In a more particular way, it is the intention to define a method and a device with which even high loads of the substances can be applied by simple means. This object is achieved for a method by the features of claim 1, and for a device by the features of claim 9. Convenient embodiments are defined by the features of the dependent claims. The advantages achieved by the invention are based on the fact that, by means of a spraying process, micronized solid substances can be applied to fibrous or sheet-like filter materials in almost unlimited quantities, in such a way that the application is It can do with extremely high loads, which are impossible in the application of a suspension. Due to these high loads, effects that until now were impossible can be achieved. The tests have indicated that, by using micronized solid substances, concentrations that are higher by a factor of ten than the concentrations reached so far can be reached. In accordance with the above, this allows to improve the selective retention capacity of the filter, and / or to influence the taste of tobacco smoke, without increasing the resistance to suction, which would be inevitable in the use of denser filter materials. employees sometimes to achieve special flavors. This convenient application of the substances to the tow of the filter ensures the activity of the latter, since no combustion, oxidation, or destruction occurs during the smoking action. Although in theory there is no limit to the amount applied, in actual practice, there is a limit to the suction resistance of the filter, which should not be too high.

According to a preferred embodiment, solid substances or homogeneous mixtures of solid substances having a maximum particle size of 50 microns, more particularly maximum of 10 microns, are used, since these extremely small particles ensure a uniform distribution, and consequently, a homogeneous effect of the filter treated as such. It has been found that it is convenient to feed, in a measured way, the solid substances, implementing the dosage or the measured introduction, to take into account the speed of production of the filter, as a result of which, it can be guaranteed that it always applies the same amount of substance, for example, per unit length of the fiber. The dosage or introduction is conveniently done by means of a feeding hopper that applies in a discontinuous way the micronized solid substances, in conjunction with a fine dispenser that operates gravimetrically, and a double screw to feed the micronized solid substances towards a transporting section that operates pneumatically . In conjunction with the feedback by means of the speed of production of the filter, it can be ensured that the same amount of micronized solid substances is always applied, for example, per unit length of the fiber.

The micronized solid particles are pneumatically transported through a solids injection nozzle, in such a way that they enter the vacuum created in a tube, as a result of which the formation of lumps is practically excluded. To optimize the distribution of solids in the air flow, and to resolve any lumping, the pneumatically transported solids / air flow are passed through a mixing zone. The actual dusting is done in a dust chamber that is open in the direction of movement of the sheet-like or fibrous filter material, so as not to obstruct the passage of the filter material. Triacetin is applied to the filter material, ie, upstream or downstream of the powder chamber, with the application of triacetin preferably upstream of the powder chamber, to further improve the adhesion of the micronized solid particles on the material of the filter. The air gap for the entry of the filter material into the dust chamber is adjustable, being adjusted in such a way as to guarantee a non-contact transport of the filter material, while preventing the appearance of solid substances introduced from the dust chamber .

In order to further optimize the application of the solids in the powder chamber, the loading condition of the filter material can be influenced by the configuration, upstream of the powder chamber, ie, separated from the powder chamber by 50 to 150 millimeters upstream thereof, and transversely to the direction of the production movement of the filter material, of an ionization rod consisting of a rod electrode and a counter-electrode. This ionization rod takes the surface of the filter material to improve the adhesion of the micronized solid particles. If a particularly large amount of micronized solid particles is to be applied to the filter material, dusting can be undertaken on both sides of the filter material. For this purpose, two nozzles can be provided in the powder chamber, which feed the micronized solid particles from below and from above. Upon leaving the dust chamber, the filter material dusted with the micronized solid particles is put together to form a filter rod, which is processed in the usual way in a finished filter. Conveniently, the outlet of the dust chamber is connected to a fan that directs air and micronized solid substances through the dust chamber, and when necessary, through a dust collector connected to the dust chamber . The vacuum that connects the outlet of the dust chamber is adjustable, and allows excess air to be extracted from the pneumatic conveyor of the solid substances. The adjustment of the vacuum in the dust chamber can be done by means of a fin applied to one side of the powder chamber. Vacuum in the fan during the production and introduction phase is conveniently kept constant, to ensure consistent product application to the filter tow, and to prevent dust from arising from the dust chamber.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be explained in greater detail on the basis of an exemplary embodiment of a device for applying substances to the fibers of a filter tow, with respect to the accompanying diagrammatic drawings, in which: 1 is a diagrammatic illustration of the device. Figure 2 is an illustration of the powder chamber with the injector nozzle attached to an amplified scale.

DETAILED DESCRIPTION OF THE INVENTION The filter tow 32 is fed in the usual manner as a folder through the extender rollers 33 (shown schematically) and a guide 35, to a device 36, where triacetin is applied to the tow folder of the filter. In the direction of movement of a bast of the filter 32, downstream of the triacetin applicator 36, the tow of the filter 32 is again passed over the extender rolls 37, before entering the air gap between two ionizing rods 39, that is, a rod electrode, and a counter electrode supplied with a negative charge potential from a load generator 41 with a spark limiter. From the air gap between the two ionizing rods 39, the tow folder of the filter 32 enters an inlet slot 43 of a powder chamber 34 (see also Figure 2), which opens in the direction of movement of the tow of the filter 32, so as not to obstruct the passage of the tow of the filter 32. The size of the air gap 43 to enter the tow of the filter 32 in the dust chamber 34, can be adjusted perpendicularly to the direction of movement of the filter. the filter tow 32, and is established in such a way as to ensure a non-contact transport of the tow of the filter 32, and to prevent the fluidized solids from leaving the dust chamber 34. In the dust chamber 34, the Stretched filter tow 32 is sprinkled with micronized solid substances, or with mixed solid substances, in a manner that will be detailed later, as indicated by the two nozzles 52 of Figure 2, located above and below the towpack of filter 32, respectively. On the opposite side to the inlet slot 43, the dust chamber 34 is provided with an outlet slot 54, wherein an injector nozzle 44 is adapted as standard for the production of the filter, where the filter tow is joined. 32 to a rod shape, and air charged with dust is sucked. The filter rod thus produced sprinkled with micronized solid particles, is then wrapped with filter paper, and cut to the length of filter rod needed to be fed in a subsequent step of production, to a cigarette making machine, where It is cut into pieces of a suitable length, and attached to the tobacco rods, to produce finished filter cigarettes. The preparation of the micronized solid substances and the mixed solid substances will now be described, which may involve physiologically safe and sensory-interesting substances, more particularly polycarboxylic acids or the acid salts of polycarboxylic acids, such as citric acid, tartaric acid, succinic acid, malic acid, ascorbic acid, as well as the acid esters of these organic polycarboxylic acids, mono-di-saccharides (e.g., glucose, sugar cane), and flavorings (vanillin, menthol, etc.). The finely milled pure micronized solid substances, or the homogeneously mixed micronized solid substances, have a maximum particle size of 50 microns, and are taken from a feed hopper 12 adapted for the processing capacity, and are put in a discontinuous manner in the fine introduction element 14, whose level is detected by the MAX / MIN sensors. As soon as the MIN level is violated, the sensors are activated, and the solid substances are filled from the feed hopper 12, deactivating the filling automatically once the MAX level is reached. The fine introduction element that operates gravimetrically 14, supplies the solid substances and the solid substances mixed by means of a double screw 16 energized by an electric motor 15, to a transport area operating pneumatically 17. The fine introduction element 14 electrically coupled with the filter making machine, ie, the entered amount per filter rod is inserted as a peak value in the electronic control 19 for the fine doser 14, the filter production speed serving as the command value of speed for the fine input element 14, and as a target value for its control. The speed of the machine is detected by an encoder 20 on the carrier 22 of the filter making machine, which cuts the endless filter rod into individual filter plugs. The solid substances introduced by the fine introduction element 14 fall freely through a tube 23 downwards to a solids injection nozzle 26. It is at this point that the pneumatic transport of solids begins, since air is blown pressurized oil-free and grease-free, through a nozzle ring, of the solids injection nozzle 26, into the tube 17 attached to the nozzle 26. The resulting vacuum inside the tube 17 enters the substances solid. To optimize the distribution of solids in the air flow, and to resolve any lumping, the solid substances / the air flow are passed through a mixing zone 18 formed by a tube that runs vertically downwards, until the dust chamber 34.

In the upper portion of the dust chamber 34, there is a wide-slot, transversely located nozzle 52, whose nozzle groove width, transversely to the production direction, ie to the direction of movement of the filter tow 32, corresponds at least to the width of the tow upstream or downstream of the triacetin applicator 36. The separation of the nozzle 52 from the tow of the filter 32 can be freely adjusted by adjusting the wide slot nozzle 52 vertically upwards or down, as indicated by arrow 54. Although a single nozzle 52 is mainly sufficient as a rule, a variant is illustrated in Figure 2, where a second wide slot nozzle 52 is applied under the tow of the filter 32. The flow of solid substances / air that arrives from the pneumatic transport section is divided upstream of the two nozzles, this division of the flow being free you adjustable. Under the filter tow 32, the dust chamber 34 is thinned to a suction extraction tube 56, whose vacuum is adjustable to allow the removal of excess air from the pneumatic transport of the solid substances. The vacuum in the dust chamber 34 is adjustable by a fin 38 provided on one side of the powder chamber. The extracted transport air charged with powder is applied to a movable dust collector 40 for cleaning. The vacuum in the dust collector 40 or in the dust chamber 34 is generated by a downstream fan 50, the vacuum in the fan 50 being kept constant during the production and introduction phase, in order to ensure a consistent application and product constant to the filter tow, and to prevent dust from coming out of the dust chamber 34. The fabric-type filter tow, whose loading condition has been influenced by the ionizing rods 39 to optimize the application of substances solid, it is sprinkled in the dust chamber 34 with the micronized solid substances, which adhere to the fibers of the tow of the filter 32, to which triacetin is applied. The tow of the extended filter 32 is subsequently passed together to an endless filter rod, and is processed in the usual way in cigarette filters, which in the next step of production, are attached to a tobacco rod by wrapping paper. . As an alternative to the tow of the filter described, also the air-permeable, tissue-type filter materials described, such as filter paper, for example, can be sprinkled with micronized solid particles by means of the device 10 described. As an alternative to the discussed mode, and as seen in the direction of transport of the filter material 32, the triacetin applicator 36 can also be located downstream of the powder chamber, of course, before the material is brought together Filter on a filter rod.

Claims

NOVELTY OF THE INVENTION Having described the above invention, it is considered as a novelty, and therefore, the content of the following is claimed as property: CLAIMS 1. A method for applying substances to the fibers of a filter material for smoking articles, characterized in that the fibrous or sheet-like filter materials (32) are dusted with micronized solid substances. 2. The method according to claim 1, characterized in that pure solid substances micronized or homogeneously mixed are used, with a maximum particle size of 50 microns, more particularly maximum of 10 microns. 3. The method according to claim 1 or 2, characterized in that the solid substances are supplied in measured quantities. _4- The method according to claim 3, characterized in that the measurement is implemented taking into account the production speed of the filter. 5. The method according to claim 1 in any of claims 1 to 4, characterized in that the measured micronized solid substances are introduced by pneumatic transport (17, 18, 26) in a powder chamber (34), through which conveys the fibrous or sheet-like filter material (32) at an angle of at least 45 ° to the transport direction of the solid substances. 6. The method according to claim 5, characterized in that the filter tow (32) provided with triacetin, is introduced into the dust chamber (34), and then joined to a filter rod. . The method according to claim 5 or 6, characterized in that the fibrous or sheet-like filter material (32) is dusted with the micronized solid substances from above and from below in the powder chamber (34). ). 8. The method according to claim as claimed in any of claims 5 to 7, characterized in that the fibrous or sheet type filter material (32) is charged by ionization upstream of the powder chamber (34), as seen in its transport direction. 9. A device for applying substances to the fibers of a filter material for smoking articles, which comprises: (a) a measuring element (12, 14, 16) for micronized solid substances, and (b) an injection nozzle (26) for pneumatically conveying the measured solid substances to a powder chamber (34), (c) a fibrous or sheet-like filter material (32) which is passed through the powder chamber (34). The device according to claim 9, characterized in that the transport path of the fibrous or sheet-like filter material (32) through the powder chamber (34), is oriented at right angles to management of pneumatic transport of the micronized solid substances. The device according to claim 9 or claim 10, characterized in that the measuring element comprises a feed hopper (12) that delivers the micronized solid substances in a discontinuous manner, and a fine introduction element (14, 16). ). The device according to claim 11, characterized in that the fine introducing element operating gravimetrically (14, 16) comprises a double screw (16) to deliver the micronized solid substances to a transport path operating pneumatically . The device according to claim 11 or 12, characterized in that the fine insertion element (14, 16) is electrically coupled to the filter making machine, in such a way that the production speed of the filter is used. filters as the actual speed value for the fine input element (14, 16), and as a target value for its control. 14. The device according to claim as claimed in any of claims 9 to 13, characterized in that the powder chamber (34) opens in the direction of movement of the fibrous or sheet-like filter material (32). 15. The device according to claim as claimed in any of claims 9 to 14, characterized in that an element (36) is configured to apply triacetin, in the transport direction of the fibrous filter material or sheet type (32) current up or downstream of the dust chamber (34). The device as claimed in any of claims 9 to 15, characterized in that the air gap (43) for introducing the fibrous or sheet-like filter material (32) into the powder chamber (34) , it can be adjusted in such a way that a non-contact transport of the filter material (32) is ensured, and the fluidized solids are prevented from flowing out. 17. The device according to claim as claimed in any of claims 9 to 16, characterized in that at the outlet of the powder chamber (34), an injection nozzle is configured to form the filter rod from the filter material. fibrous or sheet type (32). The device as claimed in any of claims 9 to 17, characterized in that ionizing electrodes (39) are configured upstream of the powder chamber (34), in the transport direction of the filter material (32) . The device as claimed in any of claims 9 to 18, characterized in that the powder chamber (34) comprises a fin (38) for establishing the vacuum in the powder chamber (34). The device according to claim as claimed in any of claims 9 to 19, characterized in that a dust collector (40) is connected to the powder chamber (34). The device as claimed in any of claims 9 to 20, characterized in that, connected to the powder chamber (34), there is a ventilator (50) to generate the vacuum in the powder chamber (34). ). 22. The device according to claim 21, characterized in that the fan (50) sucks air and micronized solid substances through the dust chamber (34) and the dust collector (40).