Cross-Reference to Related Applications

This patent application claims priority of Italian Patent Application No. 102021000013010 filed on May 20, 2021, the entire disclosure of which is incorporated herein by reference.

Technical Field of the Invention

The present invention relates to a machine for making tubular segments, in particular of the tobacco industry or the straw industry, and to the method thereof.

State of the Art

The use of tubular segments is known in the tobacco industry as components of multi-component smoking articles (possibly filled with filtering and/or cooling material and/or aerosol generators) . Similarly, tubular segments of variable length are used as straws.

The application W02017130098A1, owned by the same Applicant, describes a machine for making tubular segments which comprises: feeding means for feeding a continuous web; a forming station for forming a continuous tube which comprises a guide belt configured to receive, supported thereon, the continuous web and to carry out a progressive winding of the continuous web around a longitudinal axis; a cutting station for cutting said continuous tube to obtain a succession of tubular segments.

The forming station described in the application W02017130098A1 is similar to the forming station of traditional tobacco industry machines which are used for making filter segments intended for the production of cigarettes. In particular, along the forming station a paper web is progressively wound by means of the guide belt around a cord of filtering material until the filter rod is formed. During the path along the forming station, the guide belt allows the advancement of the filter rod as the friction force generated between the guide belt and the filter rod is greater than the resistant friction forces to which the filter rod is subjected: this is verified as the filter material contained in the filter rod generates radial forces pressing against the guide belt.

In the case of the machine for making tubular segments described in the application W02017130098A1, the same Applicant has encountered difficulty in dragging the continuous tube from the forming station to the cutting station. This difficulty is due to the fact that the continuous tube has an empty cross section (i.e., a circle-shaped cross section) or substantially empty (i.e., a circle-shaped cross section with a possible element that connects at least two points of the circle).

In this case, in fact, the continuous tube does not internally contain a material capable of generating radial forces so as to press against the guide belt of the forming station. Consequently, the guide belt of the forming station is unable to exert sufficient traction on the continuous tube in order to advance it, with the right speed, to the cutting station.

This difficulty is further accentuated in the case in which the continuous web, for example made of paper material, comprises a coating material (for example made of a plastic or water- repellent material) which makes the external surface of the tube even smoother. In this case, the traction of the guide belt of the forming station on the continuous tube is further reduced. Furthermore, this difficulty is also accentuated in the case in which the guide belt is worn.

The patent US 4474564A describes a machine for forming a continuous tube which is then cut into sections, for example to make containers.

Subject and Summary of the Invention

The object of the present invention is to provide a machine for making tubular segments which overcomes the aforementioned drawback and is, at the same time, easy and inexpensive to produce .

The object of the present invention is also a relative method for making tubular segments.

According to the present invention a machine for making tubular segments and a relative method are provided according to what is claimed in the attached claims.

The claims describe preferred embodiments of the present invention forming an integral part of the present description.

The proposed machine for making tubular segments overcomes the aforementioned drawback by using dragging means arranged at or downstream of the forming station to drag the continuous tube towards the cutting station. In detail, these dragging means are arranged above the guide belt so that the continuous tube is advanced between said guide belt and said dragging means.

Advantageously, the proposed machine ensures, by means of the combined action of the guide belt of the forming station and of the dragging means, opposed to the guide belt, sufficient traction on the continuous tube (even in the case where said continuous tube is made starting from a web of material, for example paper, having a coating material).

Brief Description of the Drawings

The present invention will now be described with reference to the attached drawings, which illustrate some non-limiting embodiments thereof, wherein:

Figure 1 illustrates a schematic side view of a first embodiment of the machine for making tubular segments according to the present invention;

- Figure 2 illustrates a cross section of the tubular segment made by the machine of Figure 1;

- Figures 3a-3d illustrate a succession of cross-sectional views of the machine of Figure 1 referred to corresponding section lines identified in Figure 1;

Figure 4 illustrates a schematic side view of a second embodiment of the machine according to the present invention;

- Figure 5 illustrates a cross section of the tubular segment made by the machine of Figure 4;

Figure 6 illustrates a schematic side view of a third embodiment of the machine according to the present invention;

- Figure 7 illustrates a cross section of the tubular segment made by the machine of Figure 6;

Figure 8 illustrates a schematic side view of a fourth embodiment of the machine according to the present invention;

- Figure 9 illustrates a schematic side view of an embodiment of the dragging means forming part of the machine object of the present invention;

- Figure 10 is a sectional view of Figure 9 referred to section

X-X.

Detailed Description of Preferred Embodiments of The Invention

According to the attached figures, reference number 1 denotes a machine for making tubular segments 2 object of the present invention .

The term "tubular segment" means a segment having a longitudinal development along a relative development axis. This segment has a preferably constant cross section.

According to Figures 2 and 5, the tubular segment 2 has an empty circular cross section (i.e., shaped like a circle) . Alternatively, according to Figure 7, the tubular segment 2 has an external tube 2a having a circular cross section (i.e., shaped like a circle) and an internal shaped insert 2b which joins at least two points of the external tube 2a. The internal insert 2b, according to Figure 7, is omega-shaped, in cross section.

It is understood that this internal insert 2b could assume any other shape with the constraint of that it will not fill the cross section of the external tube 2a. For example, the internal insert 2b could be M-shaped, in cross section, or simply join two opposite points of the external tube 2a.

The tubular segments 2 are obtained starting from at least one continuous web 4, preferably made of paper material. Furthermore, this continuous web 4 can have a coating on at least one of its faces, for example of plastic and/or water- repellent type.

In the preferred embodiment, the web 4 is made of paper material. However, it could be a web 4 made of a different material such as, for example, a material derived from cellulose and/or a polymeric plastic material and/or a biodegradable material and/or a compostable material. Furthermore, these materials can contain or be coated with plasticizing and/or water-repellent and/or solvents and/or humectant substances and/or with aromas and/or with materials having a filtering effect.

The tubular segments 2 obtained by means of the machine 1 and the method object of the present invention can be intended for the tobacco industry, that is, they can be used as components of a filter or a cigarette, for example of the HNB ("heat not burn") type. Alternatively, the tubular segments 2 obtained by means of the machine 1 and the method object of the present invention can be intended for the straw industry. The machine 1 comprises feeding means 3 for feeding the continuous web 4 configured to feed the continuous web 4 along an advancing direction X parallel to the development direction of the continuous web 4.

Preferably, the feeding means 3 comprise a reel 12 from which the continuous web 4 is unwound and suitable guide rollers 13 arranged along the advancing direction X of the continuous web

4.

The machines of Figures 1 and 4 are identical in most of their characteristics (which will be described in detail in the following) and differ in that in the machine 1 of Figure 1 the continuous web 4 maintains its thickness unchanged for the entire path, whereas in the machine 1 of Figure 4 the continuous web 4 is subjected to double folding along respective longitudinal lines to assume (before the conformation as a continuous tube 6) a three-layer configuration. In other words, in the machine 1 of Figure 1 the continuous web 4 maintains the same thickness from the reel 12 until the end of the manufacturing process of the tubular segment 2 (Figure 2) whereas in the machine 1 of Figure 4 the continuous web 4 is folded to become a continuous three-layer web (Figure 5).

For this purpose, the machine 1 of Figure 4 comprises a folding station 11 (which is arranged upstream of the forming station 5) for folding at least a first longitudinal strip of the continuous web 4 onto a second longitudinal strip of the continuous web 4 around a folding line parallel to the advancing direction X so as to obtain a multilayer web. In detail, with reference to Figure 4, the folding station 11 of the machine 1 comprises two folding members 13 configured to fold longitudinal strips of the continuous web 4 around respective longitudinal folding lines, in particular so as to obtain a three-layer web in which lateral sides have a lowered area and a prominent junction area designed to favor a closure of the continuous tube 6 as illustrated in Figure 5 (namely, a continuous tube 6 is obtained having a smooth external surface devoid of degradations) . Details of these folding members 13 and of this closure of the continuous tube 6 are described with reference to the application EP3636424A1 which is incorporated herein for reference .

According to an alternative embodiment, not illustrated, of the machine of Figure 4, the continuous web 4 could be subjected to a single fold along a respective longitudinal line to assume (before the conformation as a continuous tube 6) a double-layer configuration. In this embodiment, the folding station of the machine comprises a single folding member 13.

Furthermore, according to a further embodiment not illustrated, the continuous web 4 could be a web formed by the overlapping (and preferably gluing) of two or more continuous webs. In this case, the feeding means of the machine comprise respective reels 12 for feeding the relative continuous webs 4 and a station for overlapping (and possible gluing) the continuous webs 4 arranged upstream of the forming station 5.

As previously stated, the remaining part of the machine 1 is identical for the embodiments of Figures 1 and 4.

The machines 1 of Figures 1 and 6 are identical in most of their characteristics (which will be described in detail in the following) and differ in that in the machine 1 of Figure 6 provides for the feeding of a continuous web 4, which is intended to form the external tube 2a of the tubular segment 2 and of a further continuous web 14, which is intended to form the internal insert 2b of the tubular portion 2. Both machines 1 of Figures 1 and 6 comprise a forming station 5 (which will be described in detail in the following) for forming a continuous tube 6 which comprises a guide belt 50 configured to receive (resting thereon) the continuous web 4 and to carry out a progressive winding of the continuous web 4 around a longitudinal axis to form the continuous tube 6. The machine 1 of Figure 6 differs from that of Figure 1 as the continuous web 4 is progressively wound to form the continuous tube 6 around the shaped insert 2b formed starting from the other continuous web 14.

Furthermore, the machine 1 of Figure 6 can comprise one or more gluing devices (not illustrated) to apply one or more lines of glue in the area of at least one of the two continuous webs 4, 14 to allow the fixing of the internal insert 2b to the internal surface of the external tube 2a.

The further continuous web 14 is also preferably unwound starting from a reel 15.

The machines 1 of Figures 6 and 8 are identical in most of their characteristics (which will be described in detail in the following) and differ in that in the machine 1 of Figure 6 the continuous web 4 intended to form the external tube 2a maintains its thickness unchanged along the entire path, whereas in the machine 1 of Figure 8 the continuous web 4 intended to form the external tube 2a is subjected to a double fold along respective longitudinal lines to assume (before the conformation as a continuous tube 6) a three-layer configuration. This folding is similar to that described with reference to the machine 1 of Figure 4.

The machines 1 of Figures 6 and 8 are described in detail in the application WO2020128827A1 which is incorporated herein for reference .

According to all the embodiments described above, the machine 1 comprises a forming station 5 for forming a continuous tube 6 which comprises a guide belt 50 configured to receive (resting thereon) the continuous web 4 and to carry out a progressive winding of the continuous web 4 around a longitudinal axis to form the continuous tube 6.

In other words, the continuous web 4 is conveyed resting on the guide belt 50 which guides and folds the continuous web 4 to carry out the progressive winding thereof around the longitudinal axis until forming the continuous tube 6 (as illustrated in Figures 3a-3d). It should be noted that in Figure 3a the continuous web 4 and the guide belt 50 are illustrated with a space between the same in order to make the figure clearer; the continuous web 4 is arranged resting on the guide belt 50.

The continuous web 4 comprises a first lateral side 4a and a second lateral side 4b.

As illustrated in Figures 3b-3d, the forming station 5 comprises a forming beam 51 along which the guide belt 50 advances. This forming beam 51 is shaped so as to cause the bending of the guide belt 50 (and therefore of the continuous web 4) during its advancement. With reference to Figures 3b-3d, different sections of the forming beam 51 are illustrated at different sections of the forming station 5.

The machine 1 further comprises a gluing device 9 for applying an adhesive substance to the continuous web 4 on the first lateral side 4a of the continuous web 4 (and/or on the second lateral side 4b of the continuous web 4). According to the machine 1 of Figure 1, this gluing device 9 is arranged at the forming station 5 (Figure 3c). Alternatively, said gluing device 9 could be arranged upstream of the forming station 5.

With further reference to Figures 3a-3d, during the progressive winding of the continuous web 4, the gluing device 9 applies a line of glue along the first lateral side 4a of the continuous web 4 so that in an outlet section of the forming station 5, the first lateral side 4a and the second lateral side 4b of the continuous web 4 are overlapped and glued to one another so as to define the closure of the continuous tube 6 (as illustrated, for example, in Figure 5).

Alternatively, the first lateral side 4a and the second lateral side 4b can be arranged facing one another end-to-end so to define a continuous tube 6 without overlapping the ends of the lateral sides 4a, 4b (as illustrated, for example, in Figure 2 and in Figure 6).

Downstream of the gluing device 9 and at the forming station 5, the machine 1 can comprise a pressing member configured to press together the first lateral side 4a and the second lateral side 4b of the continuous web 4 so as to form the continuous tube 6. Furthermore, the machine 1 can comprise an activation device (not illustrated) integrated in the pressing member to operate a heat exchange on the continuous tube 6 in order to promote a temperature variation of the line of glue laid by the gluing device 9.

More in detail, in the case where the line of glue is made with a hot-melt glue, the activation device cools the line of glue. On the contrary, in the case where the line of glue is made with a water-based glue, for example PVA, the activation device operates a heating of the line of glue.

Preferably, the activation device is integrated in the pressing member. Alternatively, it could be distinct from the pressing member and be arranged downstream of the same.

The machine 1 furthermore comprises a cutting station 7 for cutting said continuous tube 6 to obtain a succession of tubular segments 2.

At the cutting station 7 the machine 1 comprises a rotating cutting head 16 which rotates around a substantially horizontal rotation axis. The cutting head 16 carries at least one cutting blade which protrudes radially from the cutting head 16 and intercepts the continuous tube 6 to cut the same transversely (i.e., in a direction substantially orthogonal to the development axis thereof) thus forming the tubular segments 2.

The machine 1 comprises dragging means 8 arranged at or downstream of the forming station 5 to drag the continuous tube 6 towards the cutting station 7. In particular, the dragging means 8 are arranged above the guide belt 50 so that the continuous tube 6 is advanced between said guide belt 50 and said dragging means 8.

Advantageously, the dragging means 8 opposite (but not necessarily facing) the guide belt 50 allow better traction on the continuous tube 6 (also in the case where said continuous tube 6 is made starting from a band of a material, for example paper, having a coating material).

Therefore, the dragging means 8 allow an adequate continuous advancing of the tube 6 even if it is not capable of generating a sufficient radial force against the guide belt 50 (since it does not have a full cross section). Advantageously, the production speed of the machine 1 can be high.

It should be noted that the dragging means 8 and the guide belt 50 can be arranged at least partially vertically aligned with one another; in other words, the dragging means 8 and the guide belt 50 are respectively arranged so as to act simultaneously on the same segment of the continuous tube 6 (Figures 1-3). In other words, the dragging means 8 and the guide belt 50 act respectively on the upper portion and on the lower portion of the same segment of the continuous tube 6.

Alternatively, the dragging means 8 and the guide belt 50 can be arranged staggered along the advancing direction of the continuous tube 6; in other words, the dragging means 8 and the guide belt 50 are respectively arranged so as to act on different segments of the continuous tube 6 (Figures 4-8). In other words, the dragging means 8 and the guide belt 50 act respectively on the upper portion of a first segment of continuous tube 6 and on the lower portion of a second segment of continuous tube 6 (at least partially distinct from the first segment of continuous tube 6 and arranged downstream of the first segment of continuous tube 6).

In particular, the dragging means 8 act on the continuous tube

6.

The dragging means 8 are arranged downstream of the gluing device 9. Furthermore, the dragging means 8 are arranged downstream of the pressing member. The dragging means 8 are arranged upstream of the cutting station 7.

According to the embodiment schematically illustrated in the figures, the dragging means 8 comprise a belt 80 which is wound around at least two pulleys 81 and which comprises a lower branch 82 and an upper branch 83 (Figure 9).

The lower branch 82 of the belt 80 is arranged to drag the continuous tube 6. The lower branch 82 of the belt 80 has a substantially longitudinal and parallel development to the development axis of the continuous tube 6.

Advantageously, this conformation of the dragging means 8 allows dragging of the continuous tube 6 at a segment having a length equal to the length of the lower branch 82 of the belt 80. In other words, the dragging action of the belt 80 on the continuous tube 6 is not of the single point of contact type; the dragging action of the belt 80 on the continuous tube 6 is at a segment (of a more or less long length) of the continuous tube 6. Advantageously, the dragging action of the belt 80 is more effective than a single point of contact type action. Furthermore, by means of a belt 80 having a lower branch 82 more or less long it is possible to adjust the dragging action exerted on the continuous tube 6.

Preferably, at least the lower branch 82 of the belt 80 has a U-shaped cross section for partially winding the continuous tube 6, in particular for winding the upper part of the continuous tube 6 (Figure 10). Advantageously, the traction on the continuous tube 6 is further improved.

Preferably, the belt 80 is made of or coated with a rubber material. Advantageously, the traction on the continuous tube 6 is further improved.

According to an embodiment not illustrated and alternative to the belt dragging means, said dragging means 8 comprise a roller having a rotation axis substantially horizontal and perpendicular to the longitudinal axis of the continuous tube 6. In this case, the dragging action of the roller on the continuous tube 6 is of the single point of contact type.

Preferably, the roller has a U-shaped external profile for partially winding the continuous tube 6, in particular for winding the upper part of the continuous tube 6. Advantageously, the traction on the continuous tube 6 is further improved.

Preferably, the roller is made of a rubber material or is coated with a rubber material at least at the area of the roller which comes into contact with the continuous tube 6. Advantageously, the traction on the continuous tube 6 is further improved.

According to a further alternative embodiment not illustrated, the dragging means 8 can comprise both the belt 80 wound around at least two pulleys 81 and the roller having a substantially horizontal and perpendicular rotation axis to the longitudinal axis of the continuous tube 6. In this case, the belt 80 and the roller are arranged one after the other (upstream of the cutting station 7) along the advancing path of the continuous tube 6.

Preferably, the dragging means 8 are motorized. The dragging means 8 can comprise at least one motor, for example of the electric type. In particular, the motor is arranged to move the belt 80 and/or the roller of the dragging means 8.

In particular, the dragging means 8 are motorized so as to drag the continuous tube 6 at a same speed with respect to the guide belt 50 of the forming station 5 (i.e., the dragging means 8 are motorized to drag the continuous tube 6 at a speed equal to the speed set by the guide belt 50 of the forming station 5). In other words, the peripheral speed of the dragging means 8 (for example, of the belt 80) is the same peripheral speed as the guide belt 50 of the forming station.

Alternatively, the dragging means 8 are motorized so as to drag the continuous tube 6 at a higher speed (even if slightly) than the guide belt 50 of the forming station 5 (i.e., the dragging means 8 are motorized to drag the continuous tube 6 at a speed greater than the speed set by the guide belt 50 of the forming station 5). In other words, the peripheral speed of the dragging means 8 is greater than the peripheral speed of the guide belt 50 of the forming station 5. In this regard, the machine 1 can comprise a control unit (not illustrated) which is connected to the motorization of the dragging means 8 and to the motorization of the guide belt 50. This control unit controls the aforementioned motorizations in order to maintain the speed of the dragging means 8 at a speed equal to or greater than the speed of the guide belt 50 in order to ensure that the continuous tube 6 is subjected to a given speed in its upper part (on which the dragging means 8 act) and to a given speed in its lower part (on which the guide belt 50 acts).

A method for making 2 tubular segments, in particular of the tobacco industry or the straw industry, is described in the following, which is also the object of the present invention.

The method comprises the steps of: feeding a continuous web 4, in particular made of paper material having a coating, along an advancing direction X parallel to the development direction of the continuous web 4; providing a forming station 5 for forming a continuous tube 6, which comprises a guide belt 50 that receives the continuous web 4 (preferably, the continuous web 4 is resting on the guide belt 50) and carrying out a progressive winding of the continuous web 4 around a longitudinal axis to form the continuous tube 6; cutting, at a cutting station 7, the continuous tube 6 to obtain a succession of tubular segments 2.

Furthermore, the method comprises the step of dragging the continuous tube 6 towards the cutting station 7 by means of dragging means 8 arranged above the guide belt 50 so that the continuous tube 6 is advanced between said guide belt 50 and said dragging means.

According to the embodiments described above, the machine 1 and the method object of the present invention advantageously allow to ensure adequate dragging of the continuous tube 6 from the forming station 5 to the cutting station 7. This advantage is also obtained in the case where the continuous tube 6 is made starting from a web material having on at least one of its faces (in particular the face intended to be the external surface of the continuous tube 6) a coating made of a plastic and/or water- repellent material. In particular, the proposed machine 1 allows adequate traction on the continuous tube 6 by means of the dragging means 8 arranged opposite to the guide belt 50 of the forming station 5.