Double-layered tube of the tobacco processing industry and method for producing such a tube

Abstract

The invention relates to a double-layered tube of the tobacco processing industry and a method for producing such a tube. When applying a positioning adhesive, it is provided to apply said adhesive with an application thickness of 10 m to 80 m.

Claims

1. A double-layered tube of the tobacco processing industry, comprising: a first material strip portion having a first width; a second material strip portion having a second width; and a positioning adhesive between the first and second material strip portions as glue applied over at least a substantial portion of an entire surface of one of the first and second material strip portions, the first and second material strip portions being wound around one another so that edges defining the first width abut each other to form one of a circular or oval shape and so that edges defining the second width abut each other to form one of a circular or oval shape, wherein the circular or oval shape of the second material strip is arranged externally around the circular or oval shaped of the first material strip, wherein the abutting edges of the first and second material strips are offset from each other in a circumferential direction, and wherein thicknesses of the first and second material strip portions range from 38 m to 160 m, and an applied thickness of the positioning adhesive ranges from 10 m to 80 m.

2. The tube according to claim 1, wherein the positioning adhesive is applied as glue over the entire surface of one of the first and second material strip portions.

3. The tube according to claim 1, wherein at least one of: the thicknesses of the first and second material strip portions range from 100 m to 140 m, and the applied thickness of the positioning adhesive ranges from 10 m to 40 m.

4. The tube according to claim 3, wherein at least one of: the thickness of the first and second material strip portions ranges from 120 m to 130 m, and the application thickness of the positioning adhesive ranges from 15 m to 30 m.

5. The tube according to claim 1, further comprising a seam adhesive provided between the first and second material strip portions as glue applied over substantially the entire length with an application thickness of 40 m to 120 m.

6. The tube according to claim 5, wherein the seam adhesive is provided with an application thickness of 60 m to 100 m.

7. The tube according to claim 1, wherein a weight of at least one of the first and second material strip portions ranges from 27 g/m.sup.2 to 125 g/m.sup.2.

8. The tube according to claim 7, wherein the weight of at least one of the first and second material strip portions ranges from 60 g/m.sup.2 to 120 g/m.sup.2.

9. The tube according to claim 7, wherein the weight of at least one of the first and second material strip portions ranges from 70 g/m.sup.2 to 110 g/m.sup.2.

10. The tube according to claim 1, wherein the offset of the abutting edges of the first and second material strip portions is between 0.5 mm to 3 mm.

11. The tube according to claim 10, wherein the offset of the abutting edges of the first and second material strip portions is between 1.5 mm to 2.5 mm.

12. The tube according to claim 1, wherein a ratio of the second width to the first width is between 52 to 48.

13. The tube according to claim 12, wherein the ratio of the second width to the first width is between 50.5 to 49.5.

14. A method for producing double-layered tubes of the tobacco processing industry comprising: conveying a base material strip in the longitudinal axial direction of conveyance; longitudinal axial cutting of the base material strip into a first material strip having a first width and a second material strip having a second width; gluing at least the second material strip over at least a substantial portion of an entire surface of the second material strip by applying a positioning adhesive with an application thickness between 10 m and 80 m; combining the first and the second material strips so as to be superimposed and offset to one another, wherein in a region in which the first and the second material strips combined to be superimposed and offset, the material strips are adhesively bonded together; shaping the superimposed material strips into a tubular rod; and cutting the rod to length into double-layered tubes.

15. The method according to claim 14, wherein the application thickness of the positioning adhesive is between 10 m and 40 m.

16. The method according to claim 14, wherein the application thickness of the positioning adhesive is between 15 m and 30 m.

17. The method according to claim 14, further comprising applying a seam adhesive to at least one region on the second material strip with an application thickness of 40 m to 120 m.

18. The method according to claim 17, wherein the seam adhesive is applied with an application thickness of 60 m to 100 m.

19. The method according to claim 17, wherein the seam adhesive is applied at least one of before and after combining the material strips.

20. The method according to claim 14, wherein the first material strip is narrower than the second material strip, and the shaped second material strip is arranged externally around the shaped first material strip, wherein a ratio of a second width of the second material strip to a first width of the first material strip is between 52 to 48.

21. The method according to claim 20, wherein the ratio of the second width to the first width is between 50.5 to 49.5.

22. The method according to claim 14, wherein a type of adhesive used for the positioning adhesive is different from a type of adhesive is used for the seam adhesive.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention is described hereinafter without limiting the general inventive idea using exemplary embodiments with reference to the drawings, wherein relative to all details according to the invention not described in more detail reference is expressly made to the drawings, in which:

(2) FIG. 1 shows a schematic sectional view through a double-layered material strip in a cutting plane transversely to the longitudinal axis of the material strips,

(3) FIG. 2 shows a correspondingly produced double-layered tube according to the invention in a schematic sectional view,

(4) FIG. 3 shows an apparatus according to the invention for producing double-layered tubes in a schematic view and

(5) FIG. 4 shows a schematic sectional view through a filter which comprises a double-layered tube.

(6) In the drawings, the same or similar elements and/or parts are provided in each case with the same reference numerals so that in each case a further description is dispensed with.

DETAILED DESCRIPTION

(7) The particulars shown herein are by way of example and for purposes of illustrative discussion of the embodiments of the present invention only and are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the present invention. In this regard, no attempt is made to show structural details of the present invention in more detail than is necessary for the fundamental understanding of the present invention, the description taken with the drawings making apparent to those skilled in the art how the several forms of the present invention may be embodied in practice.

(8) FIG. 1 shows, in a schematic sectional view transversely to the longitudinal axis of two material strips 11 and 12, the state of a first material strip 11 and of a second material strip 12 after these strips have been joined together. In this case, it may be seen that first material strip 11 has a positioning adhesive 17, for example a glue, on its upper face. Second material strip 12 is positioned onto positioning adhesive 17.

(9) First material strip 11 has left and right edges 13 and 14 and second material strip 12 has left and right edges 15 and 16.

(10) Additionally, a seam gluing (or seam glued strip) 18 may be undertaken on first material strip 11, which serves to provide an adhesive to the part of second material strip 12 extending beyond right edge 13 of first material strip 11. Seam glued strips may also be provided, for example, on one side of first material strip 11 and on an opposing side of material strip 11. Gluing 17 (or application of positioning adhesive 17) may take place at a same time as seam gluing 18 (or application of seam glue strip 18), or as already specified above, i.e., before the shaping of the tube or the tubular rod in a formatting apparatus.

(11) After passing through the formatting apparatus, in this configuration a double-layered tubular rod 10 is produced or respectively after cutting this rod 10 to length a double-layered tube is produced, which is shown schematically in cross section in FIG. 2. In this case, first material strip portion 11 is located in an interior, whereby edges 13 and 14 are arranged either to abut each other or with a small spacing from one another in an abutting region 21.

(12) Abutting region 21 is not aligned radially with (or is radially offset from in a circumferential direction) an abutting region 20 of second wrapping material strip 12, where edges 15 and 16 are arranged either to abut each other or with a small spacing from one another in an abutting region 20. The gaps of abutting regions 20 and 21 may also be provided with an adhesive. However, in the exemplary embodiment of FIG. 2, no adhesive is provided. In contrast to the prior art, an improved roundness is provided since there is no overlapping of left and right edges 15 and 16 of second wrapping material strip 12, but instead these edges are placed in an alignment to achieve a substantially circular outer contour.

(13) By the offset of abutting regions 20 and 21 in the circumferential direction, a very secure closure is produced for double-layered tube 10. Moreover, as a result, an increased stability of double-layered tube 10 is achieved since the weakened points of individual layers 11, 12 are spaced apart from one another.

(14) The thicknesses of first material strip portion 11 and of second material strip portion 12 may be of different sizes or substantially a same size relative to one another. With different thicknesses, it is preferred if the outer material strip portion, i.e., material strip portion 12, is thinner than first material strip portion 11. Preferred thicknesses according to the invention are described above.

(15) FIG. 3 shows schematically an apparatus according to the invention for producing double-layered tubes 10 of the tobacco processing industry. In this exemplary embodiment, a plurality of variants of the apparatus according to the invention is concurrently shown.

(16) From a bobbin, not shown, a correspondingly wide base material strip 24 is drawn off in a direction of conveyance 34 and deflected via rollers 41 in a material strip supply apparatus 22. A cutting apparatus (cutter) 23, which can be a longitudinal cutter, follows material strip supply apparatus 22, to cut base material strip 24 in a longitudinal direction.

(17) The cut material strip 24 produces a first material strip 25 and a second material strip 26, which are conveyed in parallel via a further deflection roller 41, in order to be separated from one another via a transverse conveyor 32 in the form of a deflection roller, whereby second material strip 26 is deflected out of the conveyance path of first material strip 25. After first material strip 25 is deflected by another deflection roller 41, first material strip 25 is substantially completely glued (or a positioning adhesive is applied thereto) via a gluing apparatus 27 at least over an entire length. This gluing apparatus 27 may, for example, omit the region of a seam but this does not necessarily have to be the case. In other embodiments, after a further deflection after transverse conveyor 32, second material strip 26 can be substantially completely glued via a gluing apparatus (not shown) at least over an entire length. Again, this gluing apparatus may also omit the region of a seam but does not necessarily have to.

(18) After transverse conveyor 32, first material strip 25 is conveyed separately from second material strip 26. Moreover, via offsetting apparatus 29, first material strip 25 and second material strip 26 are offset in the transverse direction relative to s direction of conveyance so that in a traction roller pair 28, by which first material strip 25 is combined with second material strip 26, material strips 25 and 26 are superimposed or overlap so as to be laterally offset from one another. Material strips 25, 26 are present at this point, for example, as shown schematically in FIG. 1.

(19) Subsequently, a heating apparatus 35 is provided, by which the applied glue or positioning adhesive 17 is pre-hardened. In embodiments in which seam gluing has already taken place, superimposed material strips 25 and 26 are supplied to a formatting apparatus 30. In embodiments in which seam gluing has not yet taken place, seam gluing can be effected or carried out via seam gluing apparatus 36, which is arranged between heating apparatus 35 and formatting apparatus 30.

(20) In formatting apparatus 30, an intake finger 44 is configured and arranged to press the joined material strips 25, 26 downwardly onto a formatting unit belt 43, which is guided endlessly through formatting apparatus 30 via corresponding deflection rollers 41.

(21) In formatting apparatus 30, joined material strips 25, 26 are shaped into a round shape or an oval shape in the known manner. An upper formatting unit according to this embodiment is configured as a heated upper formatting unit 37 in order to further set (harden) the glue or the applied positioning adhesive 17.

(22) Subsequently, via an apparatus for cutting to length (tube cutter) 38, double-layered tubes are correspondingly cut to the desired length from the thus formed rod 31.

(23) From here, a very rapid production is possible of corresponding tubes 10, which are cut to length from tubular rod 31 and then the glue or adhesive is ultimately cured (hardened) in rod-making machine 40, which can include a further heater (not shown in FIG. 3).

(24) In alternative embodiments, rather than cutting tubular rod 31 exiting formatting apparatus 30 into double-length tubes, tubular rod 31 can be introduced into a rod-making machine 40. To this end, produced tubular rod 31 may be introduced into rod-making machine 40 to allow the glue or adhesive to cure (harden) further via heating.

(25) Alternatively, for example, a filter tow 46 from a filter tow preparation apparatus (not shown in FIG. 3, but which would be arranged to the right of illustrated apparatus) may be guided above formatting unit 30 via the apparatus according to embodiments and supplied by a traction roller pair 42 in a direction of conveyance 47 to rod-making machine 40. Filter tow 46 may, for example, be arranged around the tubular rod 31.

(26) To hold filter tow 46 on tubular rod 31, an adhesive, for example also PVA, is applied to tubular rod 31 via an anchoring seam apparatus 45. In rod-making machine 40, a wrapping material strip may be accordingly wound around the rod, which includes an internal tubular rod and a filter tow located externally around said rod, in a formatting apparatus and thus a corresponding filter may be produced.

(27) A suitable filter therefor is shown schematically in FIG. 4 by way of example. The filter in this case is provided with the reference numeral 50. Tube 10 is located on the inside, the filter tow 48 is located on the outside and a wrapping material 49 is arranged around said filter tow 48.

(28) Gluing apparatus 27 and seam gluing apparatus 36 may be configured as flat nozzles, spin-spray nozzles or according to EP 2 974 798 A1, the disclosure of which is expressly incorporated by reference herein in its entirety. In this case, preferably a surface application of adhesive or glue is undertaken.

(29) Heating apparatus 35 may be optionally provided. This serves substantially for pre-curing or pre-hardening the adhesive or glue.

(30) For accurate alignment of the paper webs (material strips) relative to one another, in particular for adjusting the correct offset in the width thereof, corresponding sensors which identify the position of the edges of the material strips may be provided. Thus corresponding control mechanisms may be provided in order to control the position of the material strips relative to one another.

(31) For simpler round shapes, in particular of thick paper or cardboard, the material strip may be pre-bent immediately upstream of the formatting apparatus or immediately downstream of the longitudinal cutter.

(32) The double-layered tube may have an internal diameter of, for example, 3 mm to 8 mm.

(33) All of the cited features and also the features to be derived individually from the drawings and also individual features which are disclosed in combination with other features, are regarded individually and in combination as essential to the invention. Embodiments according to the invention may be fulfilled by individual features or a combination of a plurality of features. Within the scope of the invention, features which are qualified by in particular or preferably are to be understood as optional features.

(34) It is noted that the foregoing examples have been provided merely for the purpose of explanation and are in no way to be construed as limiting of the present invention. While the present invention has been described with reference to an exemplary embodiment, it is understood that the words which have been used herein are words of description and illustration, rather than words of limitation. Changes may be made, within the purview of the appended claims, as presently stated and as amended, without departing from the scope and spirit of the present invention in its aspects. Although the present invention has been described herein with reference to particular means, materials and embodiments, the present invention is not intended to be limited to the particulars disclosed herein; rather, the present invention extends to all functionally equivalent structures, methods and uses, such as are within the scope of the appended claims.

LIST OF REFERENCE NUMERALS

(35) 10 Tube 11 First material strip portion 12 Second material strip portion 13 Edge 14 Edge 15 Edge 16 Edge 17 Positioning adhesive 18 Seam adhesive 20 Abutting region 21 Abutting region 22 Material strip supply apparatus 23 Cutting apparatus 24 Base material strip 25 First material strip 26 Second material strip 27 Gluing apparatus 28 Traction roller pair 29 Offsetting apparatus 30 Formatting apparatus 31 Rod 32 Transverse conveyor 34 Direction of conveyance 35 Heating apparatus 36 Seam gluing apparatus 37 Heated upper formatting unit 38 Apparatus for cutting to length 40 Rod-making machine 41 Deflection roller 42 Traction roller pair 43 Formatting unit belt 44 Intake finger 45 Anchoring seam application apparatus 46 Filter tow strip 47 Direction of conveyance 48 Filter tow 49 Wrapping material 50 Filter