DESCRIPTION
MACHINE FOR MAKING TUBULAR SEGMENTS OF THE TOBACCO
INDUSTRY
Technical field
This invention relates to a machine for making tubular segments of the tobacco industry or of loose materials containing fibres, in particular tubular segments provided with a filling material, where the filling is obtained from a material in the form of a web, preferably of paper. In the context of this invention, the segments may form part of a traditional cigarette or a heat- not-burn cigarette and, in particular, an unfiltered cigarette or a cigarette of the hand-made or roll-your-own or make-your-own type.
In effect, in cigarettes of this kind, a spacing element must be placed between the element which burns or is heated to generate the aerosol and the smoker’s mouth so as to cool the smoke and, above all, to prevent the tobacco from reaching the smoker’s mouth. The term“tobacco” as used herein, denotes any loose material containing fibres, whether of plant or other origin.
Background art
A typical hand-made cigarette consists of a paper tube rolled around a paper filling in the form of an insert or obtained using a piece of the selfsame paper.
In a manual method for making the tube, an outer sheet of paper material is rolled into the shape of a tube and a filling insert is then placed inside the outer tube to partly fill the cavity defined by the outer tube. The insert may be made by manually folding another piece of paper material, in particular to form a specific, three-dimensional element intended to partly fill the tube and also capable of acting as a barrier preventing the passage of tobacco fragments.
These cigarettes, made basically using ready-cut paper sheets, are very convenient to make by hand but do not lend themselves to industrial
production for evident reasons of incompatibility with the production processes, in particular on account of the very low productivity attainable by working separate sheets. Working on the inserts individually is, indeed, highly time-consuming and, what is more, does not allow repeatability of the quality of the result.
Aim of the invention
In this context, the basic technical purpose of this invention is to provide a machine for making tubular segments of the tobacco industry to overcome the above mentioned disadvantages of the prior art.
More specifically, the aim of this invention is to provide a machine for making tubular segments of the tobacco industry which allows making tubes provided with at least one filling insert and which is characterized by the high speeds and repeatability typical of an industrial process.
The technical purpose indicated and the aim specified are substantially achieved by a machine for making tubular segments of the tobacco industry, comprising the technical features described in one or more of the appended claims 1 to 14.
This invention also has for an object a method for making tubular segments of the tobacco industry, comprising the technical features described in one or more of the appended claims 15 to 22.
Brief description of the drawings
The invention is described below with reference to the accompanying drawings, which illustrate a non-limiting embodiment of it and in which:
- Figure 1 schematically represents a machine according to a first embodiment of this invention;
- Figure 1 A is an enlarged view of a detail of the machine of Figure 1 ;
- Figure 2 schematically represents a machine according to a second embodiment of this invention;
- Figure 3 shows a detail of the machine of Figure 1 or 2;
- Figures 4 and 5 are cross sections of a portion of the machine of Figure 1 or 2 along two successive section planes;
- Figure 6 is a cross section of a tubular segment made with the machine of Figure 2;
- Figure 6A shows an enlarged view of the segment of Figure 6;
- Figure 7 is a detail view showing a portion of the machine of Figure 1 or 2;
- Figure 8 schematically represents an operating step carried out in the machine portion of Figure 7.
Detailed description of preferred embodiments of the invention
With reference to the accompanying drawings, the numeral 1 denotes in its entirety a machine for making tubular segments of the tobacco industry according to this invention.
In the context of this invention, the term“tubular segment of the tobacco industry” is used to denote a tube-shaped segment usable as part of a smoking article, specifically as a component of a smoking article such as a traditional cigarette or a heat-not-burn cigarette and, more specifically, an unfiltered cigarette or a cigarette of the hand-made or roll-your-own type. The function of such a segment, when used in such a smoking article, is one of filtering and/or cooling and/or flavouring and/or conducting/dissipating heat and/or of aesthetic/characteristic appearance (replicating the cross sectional shape of a specific brand).
Further, in the context of this invention, the tubular segment (labelled 100 in the accompanying drawings) is defined by an outer tube 1 10 and at least one insert 120 disposed therein to at least partly fill the duct inside the outer tube 1 10.
In an embodiment, the outer tube 1 10 and/or the insert 120 are made from respective continuous webs of a paper material; material other than paper may, however, also be used without departing from the inventive concept of this invention. More specifically, for one or both of the continuous webs, a different material might be used, selected from the following materials
(individually or mixed together):
- materials derived from cellulose: for example cellulose acetate (tow);
- tobacco, reconstituted tobacco (recon) or other materials of plant origin: for example, wheat, maize, sugar cane, hemp, sugar beet, palm, pawpaw, etc.
- polymeric plastic materials: for example, polylactic acid (PLA), polyethylene (PE), polypropylene (PP), polyvinylchloride (PVC), polyethylene terephthalate (PET), etc.
- biodegradable or compostable materials, such as the following bio plastics: Mater-Bi, PHAs (polyhydroxyalkanoates)
- metals: for example aluminium, stainless steel...
These materials may also contain:
- plasticizers, solvents or humectants: for example, triacetin (glycerin triacetate), TEC (triethyl citrate), PEG 400 (low molecular weight polyethylene glycol);
- materials which in turn generate vapours, fumes or aerosols: for example, water, glycerol, propylene glycol, etc.;
- natural or artificial flavours such as, for example, menthol, fruit extracts, sugars, liquorice, liqueur flavourings, cocoa, etc.;
- materials having a selective or adsorbent filtering effect: for example, activated carbons, silica-gel, etc.;
- materials that facilitate joining the web components by gluing: typically, PVA, plant- or animal-derived glue, starches, alginates, fats, etc.
The above materials may be present simultaneously in the web of the tube or of the insert or they may be chemically mixed or mechanically joined, for example by rolling, pressing, moulding, compression, extrusion, coating, impregnation, sintering, gluing, powder or granule or wire inclusion, etc. The web can be made using methods similar to those used for preparing paper or recon tobacco or plastic tapes (for example, pressing) or it might also be a mesh, a textile or a non-woven web.
Figure 1 shows a first embodiment of the machine 1 according to the
invention. In this embodiment of it, the machine 1 comprises first feed means 10 for feeding a first continuous web and configured to make at least a first continuous web 2 advance along a first feed path P1 and second feed means 20 for feeding a second continuous web and configured to make a second continuous web 3 advance along at least a respective second feed path P2.
The webs 2, 3 may be made of paper or other materials, depending on the type of tubular segment required.
Further, the webs 2, 3 are unwound from respective rolls 2a, 3a, preferably motor-driven.
Preferably, the webs 2, 3, at least in a step of unwinding them from the respective roll 2a, 3a are defined by a single layer.
The machine 1 also comprises a forming station 30, disposed on the first feed path P1 and configured to fold and/or deform the first continuous web 2 in such a way as to obtain a continuous web with a shaped configuration. In other words, the forming station 30 elastically and/or permanently deforms the first web 2 so that the web changes from a flat configuration to a three-dimensional configuration, in particular a laterally gathered configuration, such as to make it suitable for insertion into, thus partly filling, a continuous tube following it.
In the context of this invention, the term“shaped” referred to the first web is used to mean a three-dimensional configuration obtained by a process of elastic or permanent deformation intended to give the web a transverse cross section having a specific shape that is visible from the outside in the final tubular segment. The shape is preferably modelled on a geometrical figure or a symbol or a generic shape of varying complexity. By way of non limiting example, the shape may have a wavy configuration or it may be the shape of a star or a leaf or a letter of the alphabet (for example, an“S” or an omega) or of a logo (for example, a trademark) or a geometrical figure (square, triangle, rectangle), or a heart or other shape. In the context of this invention, the specific shape does not constitute a limitation of the invention
but only one aspect of it, insofar as the continuous web is deformed to define a specific, predetermined shape, in particular a shape that evokes a specific image or sensation in the user.
The forming station is illustrated in detail in Figure 1 A.
Advantageously, the forming station 30 is configured to operate steplessly, thus deforming the first web 2 while the first web 2 advances steplessly. This is preferably achieved thanks to the structure of the forming station 30, which is configured to make the first web 2 pass uninterruptedly through a forming gap whose transverse cross section is such as to give the first web 2 the above mentioned shaped configuration. Preferably, the forming gap is defined by a slot extending along an open line - that is to say, where the ends of the line along which the forming gap extends are spaced and do not coincide.
In an embodiment, the forming station 30 is configured to deform the first web 2 at least partly elastically. More in detail, that means folding longitudinal portions of the first web 2 relative to each other in such a way as to allow“lateral compacting” or, more generally speaking,“transverse compacting” of the first web 2, but reversibly, so that the first web 2 thus shaped retains a certain elastic tendency to return laterally to its original shape, causing it to adapt to the internal shape of the continuous tube it will next be inserted into.
In this embodiment, the forming gap extends along an open line which is at least partly, and preferably entirely, defined by a succession of curved stretches and in particular by a spline curve. The open line may also have straight stretches - for example, straight stretches alternated with curved stretches or splines - thereby compacting gently and gradually in order to prevent or limit permanent deformations.
In addition or alternatively to deforming elastically, as just described, the forming station 30 is configured to deform the first web 2 at least partly permanently, in particular to fold the first web 2 about one or more longitudinal fold lines. More in detail, that means permanently deforming
certain specific zones of the first web 2, allowing lateral compacting to a greater degree than in the case of purely elastic deformation, as well as repeatedly folding superposed layers.
In this embodiment, the forming gap extends along an open line which has one or more sharp corners defining respective longitudinal fold lines for permanently folding the first web 2.
As mentioned above, the forming station 30 may produce lateral compacting elastically or permanently, or a combination of the two, in particular with elastically deformed zones alternated with permanent fold lines.
In a preferred embodiment, shown in Figure 3, the forming station 30 comprises a pair of rollers 31 , 32 between which the first web 2 is made to pass and which have respective matchingly shaped external features 31 a, 32a (that is to say, whose profiles are shaped to match each other and are thus geometrically compatible) defining the forming gap between them. In other words, the rollers 31 , 32, rotatable about parallel axes, have respective peripheral profiles (Figure 3) which, in cross section relative to a plane passing through the respective axis, correspond to, and hence are shaped to match, each other so as to define the forming gap of substantially uniform width through which the first web 2 is shaped.
In the embodiment illustrated in Figure 1 , a forming gap of the type described above is also defined by a second forming element, hereinafter called preforming element 33, disposed upstream of the forming rollers 31 , 32 and configured to pre-shape the first web 2.
Looking in more detail, the preforming element 33 may be defined by a rigid or monolithic element provided with a fixed forming gap by which the first web 2 undergoes an initial deformation to give the first web 2 a configuration that makes it easier for it to pass through the pair of rollers 31 , 32.
In an embodiment not illustrated, the preforming element 33 may even be sufficient to act as a single forming element, in place of the pair of rollers 31 , 32.
In a preferred embodiment, the rollers 31 , 32 are, instead, structured and/or
mounted in such a way as to be held together by a predetermined force such as to compress the first web 2 passing between them. In this configuration, therefore, the size of the forming gap between the rollers 31 , 32 is defined by the thickness and compressibility of the first web 2. This advantageously allows giving the rollers 31 , 32 not only a function of forming the first web 2 but also of entraining it, where at least one of the two rollers 31 , 32 is associated with respective motor means.
Downstream of each of the aforementioned feed means 10, 20 and of the forming station 30, the machine 1 also comprises a tubular guide 40 configured to guide the first web 2 as it leaves the forming station 30 that has given it the shaped configuration and so that it keeps the shaped configuration as it proceeds from the forming station to a wrapping station 50 (described below).
In effect, the passage of the first web 2 through the tubular guide 40 in the shaped configuration allows the first web 2 to keep its shape, contrasting its tendency to return elastically to a laterally expanded configuration.
The tubular guide 40 is shown in detail in Figure 7.
Preferably, the tubular guide 40 has at least one stretch 41 whose transverse cross section progressively decreases, gradually decreasing in diameter, for example, so as to further compact the shaped first web 2 transversely before it reaches the wrapping station 50, so that the first web 2 that has already been shaped is given the required final transverse cross section.
Figures 4 and 5 show cross sections of the tubular guide 40, respectively upstream and downstream of the stretch 41 with the decreasing transverse cross section, specifically at the cross sections S1 and S2 of Figure 7.
In a preferred embodiment, the tubular guide 40 is made entirely in one piece. It may, however, also be made up of a succession of parts connected to each other to form a single rigid body.
As shown in Figure 8, the tubular guide 40 has an outlet end portion 42 with an outlet opening 43 lying in an inclined plane not perpendicular to the feed
direction of the shaped first web in such a way that the outlet opening 43 faces down.
In a further embodiment not illustrated, the tubular guide 40 may itself be a forming element if the web 2 is not required to adopt a predetermined shaped configuration and has to pass through the tubular guide 40 only. Downstream of the forming station 30 and of the tubular guide 40, the machine 1 also comprises the aforementioned wrapping station 50, where the first feed path P1 and the second feed path P2 meet and where the second web 3 is wrapped around the previously formed first web having the shaped configuration, thus obtaining a continuous tube defined by an outer covering enclosing within it the first web that has been shaped.
Looking in more detail, the wrapping station 50 is located at the end portion 42 of the tubular guide 40 from which the first web 2 comes out with the shaped configuration and the second web 3 is at least partly wrapped directly round the end portion 42 of the tubular guide 40. Wrapping is accomplished by superposing opposite lateral edges of the second web 3 and gluing them to each other.
The wrapping station preferably also comprises a belt (not illustrated) for guiding the second web 3 driven along a closed path and designed to act in conjunction with fixed deflectors for guiding the second web 3 being wrapped around the end portion 42 of the tubular guide 40.
As shown in Figure 8, the second web 3, during its initial wrapping movement around the end portion 42 of the tubular guide 40, comes from below and thus the aforementioned outlet opening 43 of the tubular guide 40 faces a central portion of the second web 3 being wrapped around the end portion 42 itself. This advantageously allows exposing a portion of the second web 3 and/or of the shaped first web 2 so that they can be glued to each other to permanently join the shaped first web 2 to the second web 3. In other words, at least the shaped first web 2 or the second web 3 have to interact with a gluing device 60 along their path in order to spread a layer of glue on at least one of the two webs 2 or 3 so as to join the two webs 2 and
3 to each other.
In a possible embodiment, the end portion 42 of the tubular guide 40 may have the shape of a truncated cone or otherwise tapered in the direction of the continuous tube being formed.
In particular, the gluing device 60, configured to apply an adhesive substance - for example, vinyl glue or PVA or hot-melt glue - on the shaped first web or on the second web 3, may be disposed in proximity to the wrapping station 50, and, more specifically, near the outlet opening 43. The gluing device 60 preferably comprises one or more spray nozzles, not illustrated, configured to direct a jet of glue on the shaped first web or on the second web 3.
In embodiments not illustrated, the gluing device may be disposed at a different position: for example, on the first and/or the second feed path P1 , P2.
Located downstream of the wrapping station 50 there is a cutting station 70 for dividing the continuous tube into a succession of tubular segments 100. The cutting station 70 may comprise a rotary blade of customary type as used, for example, to cut continuous cigarette or filter rods, and provided with a rotary drum fitted with one or more radial, preferably adjustable blades.
Figure 2 shows a second embodiment of the machine 1 according to the invention. The machine 1 of this embodiment differs from that of Figure 1 in that it comprises, on the second feed path P2, upstream of the wrapping station 50, a folding device 80 operating on the second web 3 to fold the second web 3 about two parallel, longitudinal fold lines to give the second web 3 a three-layer structure.
In this situation, the outer tube 1 10 thus made is visible in the view of Figure 6 and in the enlarged view of Figure 6A, showing the splicing zone where the opposite lateral edges of the second, three-layer web 3 are joined.
More generally, the folding device 80 disposed on the second feed path P2 may be configured to fold the second web 3 one or more times about one
or more parallel, longitudinal fold lines to give the second web 3 a multilayer structure. Folding in this way is carried out continuously by one or more fixed deflectors having respective folding edges disposed at the respective longitudinal fold line. In order to facilitate folding the second web about the longitudinal fold lines, a scoring device (not illustrated) may be provided on the second feed path P2, upstream of the folding device 80, to make one or more longitudinal lines of weakness that will constitute the fold lines in the folding device 80.
This invention is susceptible of modifications without departing from the inventive concept. By way of an example, in the case of a multilayer outer tube, for example with at least two at least partly superposed webs, two or more second webs from respective rolls (or from a single roll cut lengthways to form two webs) and wrapped in such a way as to present respective splicing zones angularly spaced about the axis of the final tubular segment can be used instead of a single second web folded about one or more longitudinal, parallel fold lines.
Furthermore, on the first feed path, there may be an applicator device for applying on the first web as the first web advances and/or after it is formed an additional substance such as a flavouring or a substance suitable for increasing the conductive and/or heat dissipative properties of the first web. According to a further optional possibility, a creasing and/or scoring device may be provided on the first feed path to make one or more lines of weakness (either continuous or with cyclic interruptions) on the first web to facilitate its subsequent deformation in the forming station. Alternatively, the first web might have these creases and/or scored cuts already made on it when it is unwound from the respective roll.
Moreover, according to this invention, the guide 40 might coincide totally or at least partly with the wrapping station 50, where the outer surface of the guide 40 allows wrapping the second web 3.
The present invention achieves the preset aims, overcoming the disadvantages of the prior art.
In effect, the invention provides a machine that is configured to implement an industrial method for making tubular segments provided with at least one filling insert, where the segments can be made from respective continuous webs, allowing high productivity and a high level of quality and repeatability.