Patent Application
20170113831
This claims priority from German Patent Application No. 10 2015 220 747.1, filed Oct. 23, 2015, the disclosure of which is hereby incorporated by reference in its entirety into this application.
With the invention, a method for producing a twin-wall cup is to be improved.
According to the invention, a method for producing a twin-wall cup from paper or paper-like material having the following steps is proposed for this purpose:
When winding an outer jacket onto an inner cup, the flat segment which is intended to form the outer jacket should be fixed to the inner cup before the actual winding operation, and therefore fixed until the conclusion of the winding operation. This is usually carried out by means of a clamping lever which presses the segment onto the inner cup. The opposing force is absorbed by a mandrel onto which the inner cup is pushed. The force needed for the secure fixing of the segment is necessarily so high that the previously applied adhesive between inner cup and segment is forced out of the pressing area. As a consequence, the air gap needed for the insulation of the cup between the inner cup and outer jacket is reduced to a non-tolerable extent in the area of the clamping lever. The finished cup is then restricted in terms of its function, possibly even unusable. In the method according to the invention, before the flat segment is laid on the inner cup, 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. The spacer is formed in such a way that it can no longer be deformed plastically or deformed only to a small extent. The spacer therefore serves to maintain the dimensions of the insulation gap even under the action of force from the clamping lever on the segment. As a result of the provision of the spacer, the segment can then be wound to form the outer jacket and it is possible to ensure that, on the finished cup, a substantially constant spacing between outer jacket and the sleeve of the inner cup is achieved. The twin-wall cup that is produced has very good insulating properties as a result.
Paper, board or paperboard, for example, is viewed as a paper material or paper-like material. For example, paper, board or paperboard can be present in flat segments, and these flat segments can then firstly be wound to form a sleeve having a circumferential wall and also deformed to form a base element that is pot-like, for example. The sleeve and the base are then connected to form an inner cup. The outer jacket is also produced from a flat segment. Expediently, the paper material is coated in a liquid-tight manner. In any case, the inner side of the inner cup should be coated in a liquid-tight manner. On the outer side of the inner cup and on the outer jacket, it is possible to dispense with a liquid-tight coating, also to make printing of the outer jacket easier. However, plastic material present in flat form, for example, is also viewed as a paper-like material if this is processed in the same way or at least in a similar way to form a cup or a lid. Flat plastic materials are also plastic laminates, for example. To produce an inner cup, outer jacket or lid, the flat plastic material which is present in segment form is likewise wound around a central mandrel and connected in the area of the overlap in order to form an in particular conical sleeve. A pot-like base or pot-like lid element can also be shaped from the flat plastic material by a circular blank being folded upward approximately vertically with respect to its bottom surface in its edge region. The problems which occur in the case of plastic material to be processed in a manner similar to paper are, however, substantially the same which occur when processing paper material. Specifically, plastic material to be processed in a paper-like manner can also not be deformed highly, for example bent, without losing its insulating properties and leak-proof properties. The present invention can be used for plastic materials to be processed in a paper-like manner but is not specifically designed for plastic materials to be processed in a paper-like manner but of course can also be used for paper material with considerable advantages.
In a development of the invention, the spacer is attached at least in the middle between the two side edges of the flat segment.
In this way, the spacer can provide an abutment when fixing the flat segment to the inner cup, and the segment can be wound to form the outer jacket with less expenditure of pressure.
In a development of the invention, the spacer on the finished cup runs in the direction from the base of the cup towards an opening of the cup.
In this way, the spacer can in particular be attached without difficulty to the segment without preventing bending of the segment during the winding of the outer jacket. Specifically, in the case of spacers running from the bottom to the opening of the cup, that is to say vertically, the spacers can also be arranged distributed over the segment and nevertheless do not hamper the bending of the segment during the winding of the outer jacket.
In a development of the invention, 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.
As a result, a spacer can be attached in a surprisingly simple way. In order to bond the outer jacket to the inner cup, nozzles for the application of adhesive are needed in any case. Before the flat segment is laid on the outer side of the inner cup, according to the invention one or more adhesive tracks are applied to the outer side of the inner cup, for example by means of a nozzle, alternatively or additionally at least one adhesive track is applied to the inner side of the flat segment. Following the solidification of this adhesive track, the latter then serves as a spacer and the flat segment can be laid on the inner cup and fixed by means of a clamping lever. The outer jacket can then be wound from the flat segment.
In a development of the invention, 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.
Paper stock is designated paper pulp. By means of a track of paper pulp, which solidifies following application, a spacer can be implemented comparatively economically. A great advantage here is that the track of paper pulp can be applied in the continuous method, for example by means of a nozzle.
In a development of the invention, 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.
A spacer can also be implemented in a simple and economical way in the continuous method by means of a foam track. Here, it is possible to use a foam which hardens automatically following application.
In a development of the invention, the spacer has a height of at least 0.2 mm and at most 5 mm, preferably between 1 mm and 3 mm.
In this way, practical spacings between outer jacket and inner cup can be implemented. Even with a spacing of 0.2 mm, a good insulating effect is achieved, a very good insulating effect at 1 mm. Up to a spacing of 5 mm, the twin-wall cup produced is sufficiently stable. Of course, this also depends on the thickness of the material of the outer jacket and on the number of bonding points between outer jacket and inner cup. In general, however, it is true that the greater the adhesive area between outer jacket and inner cup, the worse the insulating effect of the cup produced becomes.
In a development of the invention, the spacer is applied to an inner side of the flat segment and, 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.
In this way, the segment is provided with one or more spacers and the outer side of the inner cup with at least one adhesive track. As a result, both the spacer and the adhesive track can be applied in a manner unaffected by each other. As the flat segment is laid on the inner cup, although the adhesive track is compressed where it is touched by the spacer, because of the spacer or multiple spacers, a spacing is nevertheless then maintained between the outer jacket and the inner cup during the winding of the outer jacket.
In a development of the invention, 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.
In this way, a particularly uniform spacing over the entire circumference of the sleeve of the inner cup can be ensured.
In a development of the invention, 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.
The application of multiple strip-like spacers running rectilinearly to the inner side of the flat segment can be carried out in a particularly simple way in that, specifically during a linear transport movement of the flat segment, the spacers are applied by means of nozzles. On the finished cup, these strip-like spacers then run exactly in the vertical direction only in a cylindrical cup; in the case of a conical cup, the spacers then run obliquely with respect to the vertical direction. In order to arrange for the spacers on the finished cup to run exactly parallel to the vertical direction even in the case of a conical cup, these spacers can be arranged with increasing or decreasing spacing from one another on the inner side of the flat segment.
In an apparatus for carrying out the method according to the invention, at least one device, in particular a nozzle, for attaching the at least one spacer is provided.
By means of a nozzle, a spacer can be applied in a particularly simple way, for example by applying an adhesive track, a track of paper pulp or a foam track.
In a development of the invention, transport means are provided for moving the flat segment along a path that is rectilinear or circular in some sections, wherein the at least one device for attaching the spacer is arranged on a rectilinear or circular section of the path.
In this way, during the rectilinear or circular transport of the flat segment, a spacer or multiple spacers can be applied in a very simple way.
With the invention, an improved twin-wall cup of paper or paper-like material having an inner cup is provided, which cup has a sleeve and a base and is provided with 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 0.2 mm and 5 mm, in particular between 1 mm and 3 mm, is provided.
By providing one or more such spacers, it is firstly ensured that, when winding the outer jacket around the inner cup, a constant spacing between outer jacket and inner cup is achieved. Furthermore, in the event of providing multiple spacers, it is also possible to achieve the situation where a user, when gripping the cup, does not inadvertently reduce the spacing between outer jacket and inner cup. As a result, the insulating behaviour of the cup in use can be improved; the outer jacket can possibly also be made from thinner or less stable material.
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:
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.
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
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
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
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.
The illustration of
The illustration of
The illustration of
The central spacer 38 can, as illustrated in
The illustration of
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.
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.
The illustration of
The illustration of
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.
During the production of the cup 70, firstly the inner cup 72 is pushed onto the mandrel 14, see
Then, see
The illustration of
The illustration of
The illustration of
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.
The illustration of
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2015 220 747.1 | Oct 2015 | DE | national |
