METHOD FOR PRODUCING A TWIN-WALL CUP FROM PAPER OR PAPER-LIKE MATERIAL, APPARATUS FOR CARRYING OUT THE METHOD AND TWIN-WALL CUP

Abstract

Method and apparatus for producing a twin-wall cup from paper or paper-like material including placing an inner cup with a sleeve and a base onto a mandrel, laying a flat segment onto an outer side of the inner cup, opposite to the mandrel, shaping the flat segment to form an outer jacket, which surrounds the inner cup, and fixing the outer jacket on the inner cup by means of a material engagement connection of outer jacket and inner cup, in particular by means of adhesive bonding, wherein at least one spacer is attached to an inner side of the flat segment and/or to an outer side of the sleeve of the inner cup before the flat segment is laid on the inner cup.

Claims

1. Method for producing a twin-wall cup from paper or paper-like material, having the following steps: placing an inner cup with a sleeve and a base onto a mandrel, laying a flat segment onto an outer side of the inner cup, opposite to the mandrel, shaping the flat segment to form an outer jacket, which surrounds the inner cup, and fixing the outer jacket on the inner cup by means of a material engagement connection of outer jacket and inner cup, in particular by means of adhesive bonding, attaching at least one spacer to an inner side of the flat segment and/or on an outer side of the sleeve of the inner cup before laying the flat segment on the inner cup.

2. Method according to claim 1, wherein the spacer is attached at least in the middle between the two side edges of the flat segment.

3. Method according to claim 1, wherein the spacer on the finished cup runs in the direction from the base of the cup towards an opening of the cup.

4. Method according to claim 1, wherein the attachment of the spacer comprises the application and solidification of at least one adhesive track, in particular hot-melt adhesive, wherein the spacer is formed by the solidified adhesive track.

5. Method according to claim 1, wherein the attachment of the spacer comprises the application and solidification of at least one track of paper pulp, wherein the spacer is formed by the solidified track of paper pulp.

6. Method according to claim 1, wherein the attachment of the spacer comprises the application and solidification of at least one foam track, wherein the spacer is formed by the solidified foam track.

7. Method according to claim 4, wherein the adhesive track the track of paper pulp and/or the foam track is applied continuously, interruptedly or in the form of spots.

8. Method according to claim 1, wherein the spacer has a height of at least 0.2 mm and at most 5 mm, preferably between 1 mm and 3 mm.

9. Method according to claim 1, wherein the spacer is applied to an inner side of the flat segment and in that before the flat segment is laid on the inner cup, an outer side of the inner cup is provided with at least one adhesive track for fixing the outer jacket on the inner cup.

10. Method according to claim 1, wherein multiple strip-like spacers are applied distributed over the inner surface of the flat segment and/or over the outer surface of the inner cup.

11. Method according to claim 10, wherein multiple strip-like spacers running rectilinearly parallel to one another or, as viewed in the longitudinal direction of the strip-like spacers, with increasing or decreasing spacing from one another are arranged on the inner side of the flat segment.

12. Apparatus for carrying out the method according to claim 1, including at least one device, in particular a nozzle, for attaching the at least one spacer.

13. Apparatus according to claim 12, including transport means for moving the flat segment along a path that is rectilinear, at least in some sections, wherein the at least one device, in particular a nozzle, for attaching the spacer is arranged on a rectilinear section of the path.

14. Apparatus according to claim 13, including transport means for moving the flat segment along a path that is circular, at least in some sections, wherein the at least one device for attaching the spacer is arranged on a circular section of the path.

15. Twin-wall cup of paper or paper-like material comprising an inner cup which has a sleeve and a base, and having an outer jacket which surrounds the inner cup, wherein, between the inner side of the outer jacket and the outer side of the sleeve of the inner cup, at least one strip-like spacer in the form of a solidified adhesive track, a track of solidified paper pulp and/or a solidified foam track with a height between 1 mm and 5 mm is provided.

16. Twin-wall cup according to claim 15, wherein the spacer consists of a material that can be foamed, a board or a solid plastic material.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Further features and advantages of the invention emerge from the claims and the following description of preferred embodiments of the invention in conjunction with the drawings. Individual features of the different embodiments illustrated and described can be combined with one another in any desired way without exceeding the scope of the invention. In the drawings:

[0036] FIG. 1 shows a schematic illustration of a method step of the method according to the invention during production of a twin-wall cup,

[0037] FIG. 2 shows a plan view of a flat segment which, in FIG. 1, is wound to form an outer jacket,

[0038] FIG. 3 shows a schematic illustration of a method step of the method according to the invention according to a further embodiment,

[0039] FIG. 4 shows a plan view of the flat segment which, in FIG. 3, is used to produce an outer jacket,

[0040] FIG. 5 shows a sectional view of a twin-wall cup according to the invention which has the flat segment illustrated in FIG. 4 as outer jacket,

[0041] FIG. 6 shows a flat segment for producing an outer jacket in accordance with the method according to the invention, according to a further embodiment,

[0042] FIG. 7 shows a view of a cup according to the invention according to a further embodiment, wherein the sleeve of an inner cup and the outer jacket are illustrated dashed and transparently,

[0043] FIG. 8 shows a side view of the cup from FIG. 7, wherein the complete inner cup and the outer jacket are illustrated transparently,

[0044] FIG. 9 shows a plan view of a flat segment of a further embodiment of the invention,

[0045] FIG. 10 shows a plan view of a flat segment according to a further embodiment of the invention, and

[0046] FIG. 11 shows a plan view of a flat segment according to a further embodiment of the invention.

DETAILED DESCRIPTION

[0047] FIG. 1 shows, schematically, a section of an apparatus for carrying out the method according to the invention. Illustrated schematically is an inner cup 12, which has been pushed onto a mandrel 14. The inner cup 12 has a sleeve and a base connected in a substantially liquid-tight manner to the sleeve. The inner cup 12 can already be provided at its upper edge, opposite the base, with what is known as a mouth roll. The mouth roll is formed by rolling in the upper end of the sleeve and gives a user of the cup an acceptable feeling when said user places the mouth roll on the lips.

[0048] During one step of the method according to the invention, an originally flat segment 16 is wound on the inner cup 12 to form an outer jacket, which can be cylindrical or frustoconical. To this end, the flat segment 16 is laid on the inner cup at a point 18 and the flat segment 16 is then pressed against the inner cup 12 by means of a clamping lever 20. The clamping lever 20 exerts a force 22, wherein an opposing force is applied by the mandrel 14 onto which the inner cup 12 has been pushed.

[0049] At the point at which it is laid on the inner cup 12, the flat segment 16 bears a spacer 24. The spacer 24 is formed in the shape of a line or strip and, in the embodiment illustrated, consists of a solidified adhesive track. The adhesive track is applied to the segment 16 in the flat state of the latter and consists of a hot-melt adhesive. The adhesive track of hot-melt adhesive that is applied solidifies comparatively quickly as it cools down and, in the solidified state of FIG. 1, is still only slightly plastically deformable. The force 22 applied to the outer side of the segment 16 by the clamping lever 20 therefore leads only to slight plastic deformation of the spacer 24. However, it can be gathered from FIG. 1 that, on the right and left of the spacer 24, a spacing between the segment 16 and the inner cup 12 is maintained. This spacing lies between 0.2 mm and 5 mm, in particular between 1 mm and 3 mm, according to an advantageous refinement of the invention, and this spacing is achieved over the entire circumference of the inner cup 12, between the inner cup 12 and the finished outer jacket.

[0050] After the flat segment 16 has been laid and pressed on by means of the clamping lever 20, the flat segment 16 is wound to form an outer jacket. This is indicated schematically in FIG. 1 by two arrows 26. The arrows 26 are intended generally to illustrate an action of force on the segment 16, so that the latter is wound around the inner cup 12, for example by levers, fingers or half-shells 27 matched to the cup contour. A force is applied somewhat higher on the left than on the right, in order to be able to produce an overlap at the segment edges.

[0051] The segment 16 is thus laid around the inner cup 12 until the areas adjoining a first side edge 28 and a second side edge 30 overlap. The overlap that is produced is then pressed against the inner cup 12 by means of a further clamping lever 32. The segment 16 then forms an outer jacket, which is fixed in its final form by adhesive, which is not illustrated in FIG. 1. Here, the adhesive can be applied to the areas of the segment 16 which adjoin the side edges 28, 30. In the embodiment illustrated, adhesive tracks, which are not illustrated in FIG. 1, running around the inner cup 12 are applied and then connect the segment 16 to the inner cup 12. Such adhesive tracks are illustrated schematically, for example in FIG. 5, FIG. 7 and FIG. 8.

[0052] With the method according to the invention, it is possible to avoid the segment 16 coming into contact with the inner cup 12 as a result of the clamping lever 20. Instead, by means of the spacer 24, even in the area between the clamping lever 20 and the inner cup 12, a spacing between inner cup 12 and the segment 16 or the finished outer jacket is maintained.

[0053] The illustration of FIG. 2 shows the flat segment 16 before being laid on the inner cup 12. It is easy to see the spacer 24 in the form of a solidified adhesive track of hot-melt adhesive. The adhesive track can be applied, for example, by means of a nozzle 34, illustrated schematically in FIG. 2, while the flat segment is moved under the nozzle 34 in the direction of the arrows 36 by transport means, not illustrated. The transport means can be formed, for example, as a transport belt and, during a linear movement of the flat segment 16, the spacer 24 in the form of an adhesive strip of hot-melt adhesive is applied by means of the nozzle 34. As soon as this hot-melt adhesive has cooled, a solidified adhesive track is available, which then forms the spacer 24.

[0054] The illustration of FIG. 3 shows a further embodiment of the invention. As distinct from the method explained by using FIG. 1, the flat segment 16 is provided with a total of three strip-like spacers 38, 40, 42. The spacer 38 is arranged at the same position as the spacer 24 in FIGS. 1 and 2. The likewise strip-like spacers 40, 42 are arranged to be spaced apart by 90 relative to the spacer 38 and ensure that, as the flat segment 16 is wound to form an outer jacket which surrounds the inner cup 12, a constant spacing between inner cup 12 and the segment 16 and the outer jacket is also ensured at a distance from the spacer 38. By way of example, illustrated on the left is a half-shell 27, with which the left-hand section of the segment 16 is moved inward. Illustrated on the right by way of example is a finger 29, in order to move the right-hand section of the segment 16 inward and to produce the overlap. Of course, half-shells or fingers can be used on both sides.

[0055] The illustration of FIG. 4 shows the flat segment 16 from FIG. 3 with the strip-like spacers 38, 40 and 42. It can be seen from FIG. 4 that, in the longitudinal direction of the strip-like spacers 40, 38, 42, a distance between the spacers 38, 40, 42 decreases or increases, depending on the direction along the spacers 38, 40, 42 in which it is viewed.

[0056] The central spacer 38 can, as illustrated in FIG. 2, be applied by using a stationary nozzle 34, while the flat segment 16 is moved in a transport direction 44. The spacers 40, 42 can be applied with nozzles which change their position during the transport past of the segment 16. Alternatively, the spacers 38, 40, 42 can be applied one after another and an alignment of the segment 16 relative to the transport direction 44 is changed between the application of the individual spacers 38, 40, 42.

[0057] The illustration of FIG. 5 shows a sectional view of a twin-wall cup 50 according to the invention which has been produced in accordance with FIG. 3. In the sectional view of FIG. 5 it is possible to see only spacer 38. Also in FIG. 5, it is possible to see a total of three adhesive strips 52 running around the inner cup 12, which connect the frustoconical outer jacket 54 to a likewise frustoconical sleeve 56 of the inner cup 12.

[0058] The outer jacket 54 ends shortly above a base 58 of the inner cup 12 which, in the area of a bottom rib 60, is connected to the sleeve 56 in a substantially liquid-tight manner. At its upper edge, opposite the base 58, the sleeve 56 is provided with a mouth roll 62. The outer jacket 54 ends shortly underneath the mouth roll 62.

[0059] It can be seen that, on the finished twin-wall cup 50, not only the spacer 38 but also the spacers 40, 42 which cannot be seen ensure a spacing between outer jacket 54 and the sleeve 56 of the inner cup 12 when the cup is used. In addition, the adhesive tracks 52 are solidified on the finished cup 50 and prevent a user bringing the outer jacket 54 against the outer jacket 54 into contact with the sleeve 56 of the inner cup 12 and, as a result, considerably impair the insulating effect of the cup 50. Instead, by means of the invention, very stable twin-wall cups can be produced, which are also suitable for high filling quantities of hot or cold beverages.

[0060] The illustration of FIG. 6 shows a flat segment 16 which has been provided with a total of three strip-like spacers 64, 66, 68. As distinct from the spacers 38, 40, 42 of the segment 16 of FIG. 4, the strip-like spacers 64, 66, 68 are arranged parallel to one another. The spacers 64, 66, 68 can thus be applied by means of stationary nozzles during rectilinear transport of the flat segment 16.

[0061] The illustration of FIG. 7 shows a twin-wall cup 70 according to the invention according to a further embodiment of the invention. In order to be able to illustrate the inner structure of the cup 70, a sleeve 72 of the inner cup and an outer jacket 74 are illustrated transparently and merely indicated by dashed lines. A base 76 of the inner cup 72, on the other hand, is illustrated by continuous lines.

[0062] Likewise illustrated by continuous lines are a total of four strip-like spacers 78, 80, 82, 84, which run parallel to a vertical direction of the cup 70 and are arranged spaced uniformly from one another between the outer jacket 74 and the inner cup 72. Likewise illustrated by continuous lines are three adhesive tracks 86 running around the inner cup 72, which are arranged spaced uniformly from one another.

[0063] During the production of the cup 70, firstly the inner cup 72 is pushed onto the mandrel 14, see FIG. 1. The outer side of the inner cup 72 is provided with the three circumferential adhesive tracks 86.

[0064] Then, see FIG. 1, a flat segment 16, which is provided with four strip-like spacers 78, 80, 82, 84 in the form of solidified adhesive tracks of hot-melt adhesive, is laid on the inner cup 72. The segment is pressed against the inner cup 72 by means of the clamping lever 20, see FIG. 1, and the segment is then shaped to form the outer jacket 74. The shape of the outer jacket is then maintained by the adhesive action of the adhesive tracks 86, which solidify and connect the outer jacket 74 to the inner cup 72. The twin-wall cup 70 is extremely stable as a result and exhibits excellent insulating properties. The cup 70 can also be produced in a simple and economical way.

[0065] The illustration of FIG. 8 shows a side view of the cup 70 from FIG. 7, wherein once more the inner cup 72 including its base 76 and the outer jacket 74 is illustrated transparently and with dashed lines.

[0066] The illustration of FIG. 9 shows, in a plan view, a segment 90 which, according to the invention, can be wound to form an outer jacket. Arranged in the centre of the segment are multiple spacers 92 in the form of mutually parallel short strips spaced apart from one another. The spacers 92 have the shape of a circular section, which cannot be readily seen in the illustration of FIG. 9. The spacers 92 are applied, for example by means of a device, in particular a nozzle, while the segment 90 is moved along a circular path.

[0067] The illustration of FIG. 10 shows a segment 100 according to a further embodiment of the invention. Segment 100 can be wound to form a frustoconical outer jacket.

[0068] Spacers 102, 104 and 106 are arranged in the form of multiple short strips on an inner side of the segment 100. Overall, respectively five strip-like spacers 102, 104 and 106 are provided. The strip-like spacers 102, 104, 106 are applied by means of a device, in particular a nozzle, while the segment 100 is moved under the device on a path in the shape of a circular arc.

[0069] The illustration of FIG. 11 shows a segment 110 according to a further embodiment of the invention. The segment 110 can be wound to form an outer jacket. The segment 110 is provided with three spacers 112, 114 and 116 in the form of sections of a circular arc. The spacers 112, 114, 116 are arranged parallel to one another. The spacers 112, 114, 116 are applied by means of a device, in particular a nozzle, while the segment 110 is moved underneath the device along a path in the shape of a section of a circular arc.