FOLDING APPARATUS FOR FOLDING A STRAND OF FILLING MATERIAL PLACED IN CONTINUOUS ROD OF TOBACCO INDUSTRY

Abstract

 A folding apparatus (4, 4', 4", 4‴, 4"") for folding a strip of a filling material (3) placed in a continuous rod (CR) of the tobacco industry, comprising an inner folding element (20, 20', 20", 20‴) having first folding surfaces (22) situated radially around the axis (k) of the inner folding element (20, 20', 20", 20‴) and adapted to crimp the strip of the filling material (3), an outer folding element (21, 21', 21", 21‴) having second folding surfaces (23) situated radially around the axis (m) of the outer folding element (21, 21', 21", 21‴) and adapted to crimp the strip of the filling material (3), whereas the first folding surfaces (22) situated radially around the axis (k) of the inner folding element (20, 20', 20", 20‴) are arranged between the second folding surfaces (23) situated radially around the axis (m) of the outer folding element (21, 21', 21", 21‴).

Description

[0001] The object of the invention is a folding apparatus for folding a strand of filling material placed in a continuous rod of the tobacco industry.

[0002] The invention is used in the tobacco industry to manufacture paper filters.

[0003] In the tobacco industry, a commonly used method of manufacturing cigarette filters consists in forming a continuous rod filled with a filtering material and cutting such rod into individual rods from which either individual mouthpieces or individual segments are finally cut off and used to manufacture multi-segment filters. The filling material used to manufacture the continuous rod is usually a fibrous material. For many years, paper and acetate fibres have been commonly used, with the filling material usually being in the form of a strand. A problem to be solved by manufacturers of the abovementioned rods is to achieve a cylindrical rod shape. A shape error can be easily seen at the ends of the rod which should be circular, the shape of the end can be oval, and often the ends are irregular, which depends on an uneven arrangement of the filling material inside the rod, which depends on random folding of the material during the feeding of the filling material before the continuous rod is formed. The problem to obtain a circular cross-section is even greater when objects are placed inside the continuous rod. Single objects are commonly used, for example aroma capsules, tubes. Continuous objects are commonly used, for example fibres impregnated with aromatic substances. It is particularly difficult to achieve uniform folding and compaction of the material when the objects are inserted transversely to the direction of movement of the strand of filter material. For each object inserted, a uniform distribution of the filling material around the objects and/or between the objects must be achieved. So the purpose of the present invention is to correctly prepare the strip prior to object insertion.

[0004] In the prior art, devices for folding a paper strip prior to compacting it in the continuous rod production process are known. Such a solution is presented in CN105745069A which discloses an apparatus for processing a continuous strip comprising a crimped structure to be used in the production of a rod-like article, such as a filter element for a smoking article. The apparatus comprises a first roller and a second roller. The first roller and the second roller each contain several circumferentially running cams. Furthermore, the first roller and the second roller are arranged such that the circumferential cam of the first roller and the circumferential cam of the second roller are connected to each other. After conveying a continuous sheet with a crimped structure between the first roller and the second roller, the continuous sheet with the crimped structure may have an overlapping crimped structure and remain continuous, and a corrugated structure extending in the longitudinal direction of the strip.

[0005] An apparatus maintaining a separation between individual strips of crimped paper strip such as in EP3918929A1 is also known. The body of the guiding unit has a funnel-like shape. Inside the ring, separating elements are arranged in a converging channel, with at least one separating element designed to separate at least two strips is situated along the guiding unit. The upper separating element runs from the inlet to the outlet inside the compressing unit and has the shape of an oblong plate whose edges are convergent. The lower separating elements are similar in shape to the upper separating element, i.e. they are oblong and have convergent edges.

[0006] The purpose of the present invention is to develop an apparatus for folding a filling material used in the tobacco industry which will allow filling a continuous rod being manufactured and the rods cut from it so as to obtain a near-circular shape in cross-section, both when the manufactured continuous rod is filled only with the filling material and when separate objects, for example spherical objects such as capsules or oblong objects such as tubes, are placed inside the continuous rod and the individual rods. The expectation to obtain a circular shape in the cross-section of the continuous rod also applies to placing a continuous object, for example a tube, a thin rod, a string or a thread, inside the rod. An additional expectation when placing various objects in the continuous rod is to place the object centrally in the continuous rod.

[0007] The object of the invention is a folding apparatus for folding a strip of filling material placed in a continuous rod of the tobacco industry, comprising an inner folding element having first folding surfaces situated radially around the axis of the inner folding element and adapted to crimp the strip of the filling material, an outer folding element having second folding surfaces situated radially around the axis of the outer folding element and adapted to crimp the strip of the filling material. The first folding surfaces situated radially around the axis of the inner folding element are arranged between the second folding surfaces situated radially around the axis of the outer folding element.

[0008] The apparatus according to the invention is further characterised in that the first folding surfaces are situated convergently with the axis of the inner folding element, from the inlet to the outlet of the folding apparatus, and the second folding surfaces are situated convergently with the axis of the outer folding element, from the inlet to the outlet of the folding apparatus, the axis of the inner folding element being situated coaxially with the axis of the outer folding element.

[0009] The apparatus according to the invention is further characterised in that the first folding surfaces are situated convergently with the axis of the inner folding element, from the inlet to the outlet of the folding apparatus, and the second folding surfaces are situated convergently with the axis of the outer folding element, from the inlet to the outlet of the folding apparatus, the axis of the inner folding element being situated non-coaxially with the axis of the outer folding element.

[0010] The apparatus according to the invention is further characterised in that the distance of the first folding surface from the axis of the first folding element in the direction from the inlet to the outlet increases, reaches a maximum height, and then decreases.

[0011] The apparatus according to the invention is further characterised in that the angle of convergence of the second folding surface with the axis of the second folding element decreases in the direction from the inlet to the outlet.

[0012] The apparatus according to the invention is further characterised in that the first folding surfaces are uniformly arranged around the axis of the inner folding element and/or the second folding surfaces are uniformly arranged around the axis of the outer folding element.

[0013] The apparatus according to the invention is further characterised in that the first folding surfaces are non-uniformly arranged around the axis of the inner folding element and/or the second folding surfaces are non-uniformly arranged around the axis of the outer folding element.

[0014] The apparatus according to the invention is further characterised in that the first folding surfaces and the second folding surfaces are arranged alternately between each other for at least a part of the distance from the inlet to the outlet of the folding apparatus.

[0015] The apparatus according to the invention is further characterised in that the inner folding element comprises first ribs and the first folding surfaces are the ridges of the first ribs and/or the outer folding element comprises second ribs, the second folding surfaces being the ridges of the second ribs.

[0016] The apparatus according to the invention is further characterised in that the thickness of the first ribs and/or the thickness of the second ribs varies in a direction perpendicular and/or parallel to the axis of the first folding element and/or the second folding element, respectively.

[0017] The apparatus according to the invention is further characterised in that the inner folding element comprises an inner bounding surface shaped at least partially conically and/or the outer folding element comprises an outer bounding surface shaped at least partially conically.

[0018] The apparatus according to the invention is further characterised by being provided with a guiding element for guiding a strip of the filling material with an adjustable position in a transverse direction to the axis of the inner folding element or the axis of the outer folding element.

[0019] The apparatus according to the invention is further characterised in that the guiding element is in the form of a rotating element with a horizontal axis of rotation, the axial cross-section of the surface of the rotatable guiding element having an arched or near elliptical shape.

[0020] The apparatus according to the invention is further characterised by comprising a separating element situated above the axis of the inner folding element from the inlet to the outlet of the apparatus.

[0021] The object of the invention is further an apparatus for manufacturing tobacco industry rods, comprising a feeding unit for feeding the filling material, an apparatus for folding the filling material according to one of the abovementioned variants, an apparatus for feeding a wrapping material, a forming unit for forming the continuous rod, a cutting head for cutting the continuous rod into the rods.

[0022] An advantage of the apparatus is that it allows controlled folding of a single paper strip during the compaction of the strip in the folding apparatus. Further advantages of the invention include uniform folding of the filling material and obtaining a uniform density of the filling material in the manufactured rods both having no objects inside and having objects inside. The apparatus makes it possible to adapt the folding of the filling material both for continuous objects with a substantially circular cross-section and for objects with an oval, irregular, polygonal cross-section, in general with any cross-section.

[0023] The object of the invention is shown in more detail in a preferred embodiment in a drawing in which:

Fig. 1a

shows a machine for the manufacture of rods with no objects inside,

Fig. 1b

shows a machine for the manufacture of rods with individual objects inside,

Fig. 1c

shows a machine for the manufacture of rods having oblong objects inside,

Fig. 2a

shows an enlarged section of the machine of Fig. 1a with a folding apparatus,

Fig. 2b

shows an enlarged section of the machine of Fig. 1b with the folding apparatus,

Fig. 3a

shows an inner folding element in the first embodiment in a view from the outlet side of the folding apparatus,

Fig. 3b

shows a cross-section through the inner folding element of Fig. 3a,

Fig. 3c

shows a component of the inner folding element in the second embodiment,

Fig. 4a

shows an outer folding element in the first embodiment in a view from the inlet side of the folding apparatus,

Fig. 4b

shows an axial section through the outer folding element of Fig. 4a,

Fig. 4c

shows a component of the outer folding element in the second embodiment,

Fig. 5

shows the folding apparatus in the first embodiment comprising the inner folding element of Fig. 3a and the outer folding element of Fig. 4a,

Fig. 6

shows the folding apparatus in the second embodiment comprising the inner folding element of Fig. 3c and the outer folding element of Fig. 4c,

Fig. 7

shows the inner folding element in the third embodiment in a view from the outlet side of the folding apparatus,

Fig. 8

shows the outer folding element in the third embodiment in a view from the inlet side of the folding apparatus,

Fig. 9 and Fig. 10

show the folding apparatus in the third embodiment,

Fig. 11a and Fig. 11b

show a section of the machine for the manufacture of rods, including the folding apparatus provided with a fixed guiding element,

Fig. 12a, b, c

show a section of the machine for the manufacture of rods, including the folding apparatus provided with a rotating guiding element,

Fig. 13a, b

show a section of the machine for the manufacture of rods, including the folding apparatus in the fourth embodiment for folding a strip of material around a continuous element,

Fig. 14

shows the folding apparatus in the fifth embodiment,

Fig. 15

shows the folding apparatus in the sixth embodiment,

Fig. 16

shows the folding apparatus in the seventh embodiment.

[0024] A machine 1 for the manufacture of rods R from a continuous filling material 3 shown in Fig. 1a comprises a feeding unit 2 for feeding a strip of the filling material 3, a folding apparatus 4 for folding the strip of the filling material 3, a forming unit 5 for forming a continuous rod CR and a cutting head 6 for cutting the continuous rod CR of the tobacco industry into individual rods R. The machine 1 shown in Fig. 1a is adapted to manufacture rods filled with the filling material 3 and having no objects inside. Fig. 1b shows a machine built like the machine in Fig. 1a adapted to manufacture the rods R having inside individual objects such as capsules, tubes, etc.. Fig. 1c shows a machine built like the machine in Fig. 1a adapted to manufacture the rods R having oblong objects inside with the length of the rod R cut from a continuous object.

[0025] The feeding unit 2 comprises an unwinding unit 7 in which a bobbin 8 of the strip of the filling material 3 is located, and a tensioning unit 9 for maintaining a constant tension of the filling material 3. The forming unit 5 comprises a formatting bar 10, an adhesive apparatus 11 and a wrapping unit 12. Between the feeding unit 2 and the folding apparatus 4, there may be arranged a crimping unit 13 which is used to crimp or longitudinally cut the strip of the material 3. The filling material 3 is a material selected from a group comprising paper, acetate, or any other fibrous material. The wrapping material 14 is supplied from a supplying unit 15 and is typically in the form of a paper tape unwound from a bobbin.

[0026] The strip of the material 3 is unwound from the bobbin 8, passes through the tensioning unit 9 and is fed to the folding apparatus 4 where the filling material 3 is folded and compacted. Before feeding the strip of the filling material 3 to the folding apparatus 4, it may be additionally crimped or cut in the crimping unit 13. The folding of the filling material 3 is carried out by means of inner folding surfaces and outer folding surfaces of folding elements, as is discussed below in this description. The folded and compacted strip of the material 3 is formed into a cylindrical shape and is wrapped with the wrapping material 14 so as to obtain a continuous rod CR, whereas the adhesive from the adhesive apparatus 11 is fed to glue the wrapping material. The continuous rod CR is cut into the individual rods R by means of the cutting head 6. The produced rods R are used to manufacture tobacco industry articles, and are cut into individual mouthpieces or segments for multi-segment filters.

[0027] The folding apparatus 4 for folding the strip of the filling material 3 shown in simplified terms in Fig. 2a comprises an inner folding element 20 and an outer folding element 21. The inner folding element 20 shown with a dashed line is situated inside the outer folding element 21. The filling material moves in the direction T. The inlet of the folding apparatus 4 is marked as 40, the outlet of the folding apparatus 4 is marked as 41. The folding apparatus shown in Fig. 2b is a fragment of the machine shown in Fig. 1b adapted to manufacture rods provided with individual objects. In the embodiment shown, downstream of the folding apparatus 4, there is an inserting unit 35 for placing capsules inside the formed continuous rod CR. Such unit may comprise, for example, an inserting wheel 44 (Fig. 11a) or another inserting element.

[0028] The inner folding element 20 in the first embodiment shown in Fig. 3a and Fig. 3b has first folding surfaces 22 arranged around the axis k of the inner folding element 20. In the shown embodiment of the folding apparatus 4, the inner folding element 20 comprises first ribs 24, the first folding surface 22 being the ridge of the first rib 24. The first folding surfaces 22 are arranged radially to the axis k, the first folding surfaces 22 being arranged circularly around an inner bounding surface 26, which means that the folding surfaces are arranged on the bounding surface 26 at angular intervals on radii extending substantially from the axis k of the inner folding element 20, the inner bounding surface 26 being shaped at least partially as a cone. The inner bounding surface 26 may be in the form of a cone fragment, i.e. it may be shaped partly as a cone, it may comprise flat fragments or surfaces having irregular or regular curvatures. Fig. 3c shows an inner folding element 20' having the first folding surfaces 22 as in Fig. 3b, the inner folding element 20' comprising profiled bars 28, the bar 28 being shaped similar to the ridge of the first rib 24. The bars 28 are fixed on rings 29 and 30. The outer folding element 21 is shown in the first embodiment in Fig. 4a and Fig. 4b and has second folding surfaces 23 arranged around the axis m of the outer folding element 21, the second folding surfaces 23 being positioned radially to the axis m. The outer folding element 21 comprises second ribs 25, the second folding surface 23 being the ridge of the second ribs 25. The second folding surfaces 23 are arranged circularly inside the outer bounding surface 27, whereas the outer bounding surface 27 may be partly shaped as a cone. The outer bounding surface 27 may be in the form of a cone fragment, i.e. it may be shaped partly as a cone, it may comprise flat fragments or surfaces having irregular or regular curvatures. Fig. 4c shows an outer folding element 21' having the second folding surfaces 23 as in Fig. 4b, the element 21' comprising profiled bars 31, the bar 31 being shaped similar to the ridge of the second rib 25. The bars 31 are fixed on rings 32 and 33.

[0029] The folding apparatus 4 in the first embodiment shown in Fig. 5 comprises the inner folding element 20 of Fig. 3a and the outer folding element 21 of Fig. 4a positioned relative to each other so that the axis k of the inner folding element 20 and the axis m of the outer folding element 21 coincide. The first folding surface 22 is situated between the second folding surfaces 23, the second folding surface 23 is situated between the first folding surfaces 22. The first folding surfaces 22 and the second folding surfaces 23 are arranged circularly around the axes k, m, respectively. In this embodiment, both the first folding surfaces 22 and the second folding surfaces 23 are arranged uniformly around the convergent axes k, m. It is possible to position the axes k and m at a small angle or non-coaxially parallel to each other. Fig. 6 shows a folding apparatus 4' in the second embodiment. The folding apparatus 4' comprises the inner folding element 20' shown in Fig. 3c and the outer folding element 21' shown in Fig. 4c. The first folding surfaces 22 and the second folding surfaces 23 are arranged similar to the first embodiment. The first folding surfaces 22 and the second folding surfaces 23 alternate between each other for at least a part of the distance from the inlet 40 to the outlet 41 of the folding apparatus 4, 4'.

[0030] The first folding surfaces 22, the second folding surfaces 23, the inner bounding surface 26 and the outer bounding surface 27 form a folding channel 34. In the embodiment shown in Fig. 5, the strip of the filling material 3 moves in the folding channel 34 and is uniformly folded. The folding of the filling material 3 in Fig. 5 and in the other figures is shown in simplified terms. The non-coaxiality or non-parallelism of the axes k and m of the folding elements 20 and 21 can be used to non-uniformly fold the strip of the filling material 3 and to alter the degree of compaction of the material around the axes k, m in a controlled manner.

[0031] The inner folding element 20 and the outer folding element 21, shown generally in Figs. 2a, 2b, are arranged so that the inlet side 20A (Fig. 3b) of the inner folding element 20 is on the inlet side 40 of the folding apparatus 4 (Fig. 2). The inlet side 21A (Fig. 4b) of the outer folding element 21 is also situated on the inlet side 40 of the folding apparatus 4. The outlet side 20B, 21B of the inner folding element 20 and the outer folding element 21, respectively, are situated on the outlet side 41 of the folding apparatus 4. The first folding surface 22 is situated convergently with the axis k of the inner folding element, from the inlet 40 to the outlet 41 of the folding apparatus 4. The second folding surface 23 is situated convergently with the axis m of the outer folding element 21, from the inlet 40 to the outlet 41 of the folding apparatus 4, i.e. in the direction of movement T of the strip of the filling material 3. The height h1 of the first rib 24, measured from the inner bounding surface 26, may be variable. The height h1 of the first rib 24 decreases from the inlet 40 to the outlet 41 of the folding apparatus 4, the first rib 24 being rounded on the side of the inlet 40. The distance d of a point on the first folding surface 22 from the axis k varies so that from d1 at the inlet 40 the distance d increases from d1 to d2 and then decreases from d2 via d3 to d4 at the outlet 41. The height h2 of the second rib 25, measured from the outer bounding surface 27, may be variable. The height h2 of the second rib 25 varies from the inlet 40 to the outlet 41, namely first increasing and then decreasing, the second rib 25 being rounded on the side of the inlet 40. Increasing the height of the ribs allows the filling material 3 to be crimped to a greater extent, whereas the folding accomplished in such a way allows obtaining a near circular shape in the cross-section of the continuous rod CR. Similarly, increasing the number of ribs allows folding the filling material to a greater extent and obtaining a near-circular shape in the cross-section of the continuous rod CR.

[0032] The strip of the filling material 3 is supplied to the folding apparatus 4 in a flat form and is re-formed from a flat configuration to a substantially circular configuration around the axes k, m in the folding channel 34 as shown in Fig. 5, the strip of the filling material 3 being situated between the first folding surfaces 22 and the second folding surfaces 23. The inner folding surfaces 22 are arranged uniformly around the axis k and the outer folding surfaces 23 are arranged uniformly around the axis m, in this case around the same axis.

[0033] In the embodiment shown in Fig. 7, an inner folding element 20" is provided with the first ribs 24' which are non-uniformly arranged around the axis k of the inner folding element 20". The thickness g of the first rib 24 is variable in the direction of movement T of the filling material 3, i.e. in a direction substantially parallel to the axis k. The thickness g on the side of the inlet 40 is greater than the thickness g' on the side of the outlet 41. Furthermore, the thickness g of the first rib 24 may be variable in a direction transverse to the direction of movement T of the filling material 3, i.e. in a direction substantially perpendicular to the axis k. The thickness g" (shown in Fig. 9) at the inner bounding surface 26 is greater than the thickness g on the ridge of the rib 24. Fig. 8 shows an outer folding element 21" provided with the second ribs 25 which have a variable thickness f. The thickness f of the second rib 25 is variable in the direction of movement T of the filling material 3, i.e. in a direction substantially parallel to the axis m. The thickness f on the side of the inlet 40 is greater than the thickness f" on the side of the outlet 41. Furthermore, the thickness f of the second rib 25 is variable in a direction transverse to the direction of movement T of the filling material 3, i.e. in a direction substantially perpendicular to the axis m. The thickness f at the outer bounding surface 27 is greater than the thickness f' on the side of the axis m. The first ribs 24 are non-uniformly arranged around the axis k. The second ribs 25 are also non-uniformly arranged around the axis m. The arrangement of the second ribs 25 of the outer folding element 21" is aligned with the arrangement of the first ribs 24 of the inner folding element 20" of Fig. 7. The inner folding element 20" and the outer folding element 21" are arranged together in Fig. 9, with the axis k and the axis m coinciding, while in Fig. 10 the inner folding element 20" and the outer folding element 21" arranged together so that the axis k and the axis m are not coaxial, the axis k of the inner folding element 20" being situated above the axis m of the outer folding element 21". By arranging the elements 20" and 21" in this way, a higher compaction in the upper part of the folding channel 34 is achieved due to increased folding of the filling material 3. When the axis k of the inner folding element 20" is situated below the axis m of the outer folding element 21", a higher compaction in the lower part of the folding channel 34 is achieved. By adjusting the position of the inner folding element 20" relative to the outer folding element 21", a gradual variation in the compaction of the filling material 3 in the manufactured continuous rod CR can be achieved. The uniformly arranged folding of the filling material 3 makes it possible to obtain a central position of the objects inside the continuous rod CR.

[0034] In Fig. 11a, in a cross-section along the axis r of a forming channel 42, there can be seen a separating element 43 which can also be seen in Fig. 9 and Fig. 10. The separating element 43 is situated above the axis or tangentially to the axis k of the inner folding element 20 from the inlet 40 into the forming channel 42. The separating element 43 is in the form of a plate of decreasing width, i.e. of a width close to the radius of the outer bounding surface 27 at the inlet 40 and further of decreasing width to the outlet 41 and further into the forming channel 42. Further in the direction of movement T of the strip of the material 3, the separating element 43 reaches the inserting wheel 44 for inserting individual objects 45, for example capsules, into the strip of the filling material 3. The separating element 43 separates the edges 3A, 3B the strip of the filling material 3 both in the folding apparatus 4 and in the forming channel 42. The use of the separating element 43 facilitates the insertion of the capsules 45 by separating the edges 3A, 3B.

[0035] The folding apparatus 4 can be provided with a guiding element along which the filling material 3 is conveyed before feeding it for folding . Fig. 11a and Fig. 11b show a non-rotational guiding element 46 which is in the form of an arc. The non-rotational guiding element 46 has an adjustable position and is adapted to alter its position in a direction transverse to the axis k of the inner folding element 20 or the axis m of the outer folding element 21. The non-rotational guiding element 46 is mounted on a bracket 47 which is provided with an adjustment in the direction S, i.e. in a direction transverse to the axis k or m of the folding elements 20, 21. Fig. 12a and Fig. 12b show a rotational guiding element 48 with a horizontal axis of rotation p, the surface 48A of the rotational guiding element 48 having an arched or near elliptical shape in cross-section. The rotational guiding element 48 is also provided with an adjustment in the direction S. An alteration in the position of the non-rotational guiding element 46 or the rotational guiding element 48 has the effect of varying the degree of compaction of the filling material 3 in the continuous rod CR, a movement of the guiding element 46, 48 downwards causes an increase in compaction in the lower part of the folding apparatus, i.e. in the area of the edges 3A, 3B. In the embodiment of Fig. 12a, an inserting wheel 49 for placing the tubes 50 in the continuous rod CR is shown. As in the case of the capsules 45, the separating element 43 facilitates the insertion of the tubes 50 between the fibres of the filling material 3.

[0036] The folding apparatus 4" shown in Fig. 13a is a fragment of the machine shown in Fig. 1c, adapted to manufacture the rods R provided with oblong objects. In the embodiment shown, upstream of the folding apparatus 4, there is a supplying unit 36 for supplying the continuous object 50 into the continuous rod CR being formed. The continuous object 50 may have a transverse circular, oval, polygonal, multi-armed or any other cross-section. In the embodiment shown, the continuous object 50 is in the form of a tube. Fig. 13b shows an embodiment of the folding apparatus 4" adapted to fold the filling material 3 around the continuous object 50 fed centrally through by the inner folding element 20". The continuous object 50 is fed through an opening 51 in the inner folding element 20". The folding apparatus 4" can be adapted to any other cross-section of the continuous object 50.

[0037] Fig. 14 shows an embodiment wherein the first ribs 24' and the second ribs 25' have an increased height at the side of the inlet 40 relative to the first ribs 24 and the second ribs 25 in the previous embodiments. The first folding surfaces 22 and the second folding surfaces 23 are shaped in any of the ways discussed above. The first rib 24' may be provided with a slidably mounted foot 53 and is adapted to an alteration in position according to the direction U around the axis k. The second rib 25' may be provided with a slidably mounted foot 54 and is adapted to an alteration in position according to the direction U around the axis m. The variation in position of the first folding surfaces 22 and/or the second folding surfaces 23 around the axis k of the inner folding element 20 or the axis m of the outer folding element 21 may be used in any of the embodiments discussed above. Thus, it is possible to shape the folding channel 34 variously and in any manner and to adapt the folding of the filling material to the production requirements.

[0038] Fig. 15 shows an embodiment wherein the folding apparatus is provided with a single first folding surface 22 and two second folding surfaces 23, the first folding surface 22 being positioned between the two second folding surfaces 23. An embodiment wherein a single second folding surface 23 is situated between the two first folding surfaces 22 is also possible.

[0039] Fig. 16 shows a folding apparatus 4ʺʺ comprising the inner folding element 20‴ and the outer folding element 21‴. The first folding surfaces 22 of the inner folding element 20‴ and the second folding surfaces 23 of the outer folding element 21" are arranged such that the folding channel 34 has a width that varies over a small range or is substantially constant. The position of the first folding surfaces 22 and the second folding surfaces 23, and thus of the folding channel 34, may be variable. The position of the first folding surfaces 22 is defined by the distance e from the axis k. The distance e from the axis k in the lower part of the folding apparatus 4ʺʺ is greater than the distance e' in the upper part of the folding apparatus 4ʺʺ. In the embodiment shown, the distance e of the successive inner folding surfaces 22 gradually decreases to e'. The distance e may be constant for all first folding surfaces 22. The position of the second folding surfaces 23 is defined by the distance c from the axis m. The distance c from the axis m in the lower part of the folding apparatus 4‴ is greater than the distance c' in the upper part of the folding apparatus 4"". In the embodiment shown, the distance c of the successive inner folding surfaces 23 gradually deceases to c'. The distance c can be constant for all second folding surfaces 23. The folding apparatus 4ʺʺ can be used for the low-strength filling material 3.

List of designations		41	outlet of folding apparatus
1	rod manufacturing machine	42	forming channel
2	feeding unit	43	separating element
3	filling material	44	object/capsule inserting wheel
3A, 3B	edges of strip of filling material	45	inserted objects, capsules
4, 4' ,4", 4‴, 4""	folding apparatus	46	non-rotational guiding element
5	forming unit	47	bracket of guiding element
6	cutting head	48	rotational guiding element
7	unwinding unit	49	tube inserting wheel
8	bobbin of material strip	50	inserted continuous objects, tubes
9	tensioning unit	51	hole in inner folding element 20'"
10	format bar	53	foot of first rib 24'
11	adhesive apparatus	54	foot of second rib 25'
12	wrapping unit
13	crimping unit	d	distance of first folding surface from axis k
14	wrapping material	e	distance of first folding surface from axis k
15	supplying unit	c	distance of second folding surface from axis m
20, 20', 20", 20'"	inner folding element
20A	inlet side of inner folding element	h1	height of first rib
20B	outlet side of inner folding element	h2	height of second rib
21, 21', 21ʺ,21ʺ	outer folding element	g	thickness of first rib on inlet side
21A	inlet side of outer folding element	g'	thickness of first rib on outlet side
21B	outlet side of outer folding element	gʺ	thickness of first rib at inner bounding surface
		f	thickness of second rib
22	first folding surfaces	f'	thickness of second rib on inlet side
23	second folding surfaces	f"	thickness of second rib on outlet side
24, 24'	first ribs
25, 25'	second ribs	k	axis of inner folding element
26	inner bounding surface	m	axis of outer folding element
27	outer bounding surface	p	horizontal axis of rotation of rotational guiding element
28	profiled bars
29, 30	fastening rings	r	axis of forming channel
31	profiled bars
32, 33	fastening rings	S	direction of guiding element adjustment
34	folding channel	T	direction of movement of filling material
35	inserting unit	U	direction of movement of ribs
36	supplying unit	CR	continuous rod
40	inlet of folding apparatus	R	rod

Claims

1. A folding apparatus (4, 4', 4", 4", 4"") for folding a strip of filling material (3) placed in a continuous rod (CR) of the tobacco industry, comprising

an inner folding element (20, 20', 20", 20‴) having first folding surfaces (22) situated radially around the axis (k) of the inner folding element (20, 20', 20", 20'") adapted to fold the strip of the filling material (3),

an outer folding element (21, 21', 21ʺ, 21‴) having second folding surfaces (23) situated radially around the axis (m) of the outer folding element (21) adapted to fold the strip of the filling material (3),

whereas the first folding surfaces (22) situated radially around the axis (k) of the inner folding element (20, 20', 20", 20"') are arranged between the second folding surfaces (23) situated radially around the axis (m) of the outer folding element (21, 21', 21ʺ, 20‴).

2. The apparatus as in claim 1, characterised in that the first folding surfaces (22) are situated convergently with the axis (k) of the inner folding element (20, 20', 20", 20‴), from the inlet (40) to the outlet (41) of the folding apparatus (4, 4', 4", 4‴, 4""), and the second folding surfaces (23) are situated convergently with the axis (m) of the outer folding element (21, 21', 21", 21‴), from the inlet (40) to the outlet (41) of the folding apparatus (4, 4', 4", 4‴, 4ʺʺ), the axis (k) of the inner folding element (20, 20', 20", 20‴ ) being situated coaxially with the axis (m) of the outer folding element (21, 21', 21", 21‴).

3. The apparatus as in claim 1, characterised in that the first folding surfaces (22) are situated convergently with the axis (k) of the inner folding element (20, 20', 20", 20"'), from the inlet (40) to the outlet (41) of the folding apparatus (4, 4', 4", 4‴, 4ʺʺ), and the second folding surfaces (23) are situated convergently with the axis (m) of the outer folding element (21, 21', 21", 21‴), from the inlet (40) to the outlet (41) of the folding apparatus (4, 4', 4", 4‴, 4ʺʺ), the axis (k) of the inner folding element (20, 20', 20", 20") being arranged non-coaxially with the axis (m) of the outer folding element (21, 21', 21ʺ, 21‴)

4. The apparatus as in claims 1 to 3, characterised in that the distance (d) of the first folding surface (22) from the axis (k) of the first folding element (20, 20', 20", 20‴) in the direction from the inlet (40) to the outlet (41) increases, reaches a maximum height, and then decreases.

5. The apparatus as in any of the claims 1 to 4, characterised in that the angle of convergence (a) of the second folding surface (23) with the axis (m) of the second folding element (21, 21', 21ʺ, 21‴) decreases in the direction from the inlet (40) to the outlet (41).

6. The apparatus as in any of the claims 1 to 5, characterised in that the first folding surfaces (22) are uniformly arranged around the axis (k) of the inner folding element (20, 20', 20", 20"') and/or the second folding surfaces (23) are uniformly arranged around the axis (m) of the outer folding element (21, 21', 21ʺ, 21‴).

7. The apparatus as in any of the claims 1 to 5, characterised in that the first folding surfaces (22) are non-uniformly arranged around the axis (k) of the inner folding element (20, 20', 20", 20"') and/or the second folding surfaces (23) are non-uniformly arranged around the axis (m) of the outer folding element (21, 21', 21ʺ, 21‴).

8. The apparatus as in any of the claims 1 to 7, characterised in that the first folding surfaces (22) and the second folding surfaces (23) are arranged alternately between each other for at least a part of the distance from the inlet (40) to the outlet (41) of the folding apparatus (4, 4', 4", 4‴, 4ʺʺ).

9. The apparatus as in any of the claims 1 to 8, characterised in that the inner folding element (20, 20', 20", 20"') comprises first ribs (24, 24') and the first folding surfaces (22) are the ridges of the first ribs (24, 24') and/or the outer folding element (21, 21', 21", 21‴) comprises second ribs (25, 25') and the second folding surfaces (23) are the ridges of the second ribs (25, 25').

10. The apparatus as in any of the claims 1 to 9, characterised in that the thickness (g) of the first ribs (24, 24') and/or the thickness (f) of the second ribs (25, 25') varies in a direction perpendicular and/or parallel to the axis (k, m) of the inner folding element (20, 20', 20", 20'") and/or the outer folding element (21, 21', 21ʺ, 21‴), respectively.

11. The apparatus as in any of the claims 1 to 10, characterised in that the inner folding element (20, 20', 20", 20"') comprises an inner bounding surface (26) shaped at least partially conically and/or the outer folding element (21, 21', 21ʺ, 21‴) comprises an outer bounding surface (27) shaped at least partially conically.

12. The apparatus as in any of the claims 1 to 11, characterised by being provided with a guiding element (46, 48) for guiding a strip of the filling material (3) with an adjustable position in a transverse direction to the axis (k) of the inner folding element (20, 20', 20", 20'") or the axis (m) of the outer folding element (21, 21', 21ʺ, 21‴).

13. The apparatus as in any of the claims 1 to 11, characterised in that the guiding element (48) is in the form of a rotating element with a horizontal axis of rotation (p), the axial cross-section of the surface (48A) of the rotatable guiding element (48) having an arched or near elliptical shape.

14. The apparatus as in any of the claims 1 to 13, characterised by comprising a separating element (43) situated above the axis (k) of the inner folding element (20, 20', 20", 20'") from the inlet (40) to the outlet (41) of the folding apparatus (4, 4', 4", 4'", 4"").

15. The apparatus for manufacturing tobacco industry rods, comprising a feeding unit (2) for feeding the filling material (3), an apparatus (4, 4', 4", 4‴, 4"") for folding the filling material (3) according to any of the claims 1 to 14, an apparatus (15) for feeding a wrapping material (14), a forming unit (5) for forming the continuous rod (CR), a cutting head (6) for cutting the continuous rod (CR) into the rods (R).

Drawing