EP1905698B1 - Container with a tear open lid, tear open lid and tear open lid ring - Google Patents

Abstract

The container (1) has a tear-off lid (2). The cut edge of the take-out opening of the lid is arranged within the connection area of the lid to the container component (4). Independent claims are included for the following: (1) tear-off lid; and (2) manufacture of container.

Description

Background of the invention

The invention relates to a container with a tear-open lid. Furthermore, the invention relates to a tear-open lid for a container and a tear-open lid ring, as used to form a tear-open lid. Furthermore, the invention relates to a method for producing a container with a tear-open lid and a method for producing a tear-open lid or a tear-open lid ring.

State of the art

It is known to carry out lid for can or can-like packaging or container as the container on top of the permanently attached metal lid, which form a removal opening, the up to the first use of the package contents by a heat-seal applied, tearable film, in particular metal foil or Composite foil, is closed. An additional, arranged over the metal lid lid made of plastic makes the container during the period of use for the contents again closed. The FIGS. 1 to 8 show such a container and serve to illustrate manufacturing steps in the production of such cover according to the prior art.

Processing facilities for the production of metal lids with tear-off generally have on a machine frame several linear or circular processing stations arranged and a conveyor, which promotes the lid from the beginning of the device, where preformed lid parts enter the device to the end of the device where the finished lid on slides in trays arrive. FIG. 2 shows (only cut-to-length) stacked metal lid blanks 20 as an example of lid parts. These blanks 20 are for example round metal discs of eg 11 cm diameter. Of course, other basic shapes, such as square, oval or rectangular discs and other diameters are readily possible. The blanks 20 have already been preformed in a processing machine, not shown, at its edge, as described later FIG. 2 is explained. This edge forming is suitable for a rabbet joint of lid and container sump. In the FIG. 2 and the following figures, only one sector of the entire disk is shown to simplify the drawing. In the first processing station, an opening 26 is punched into the disc by punching with upper and lower tool, which in FIG. 3 can be seen, in which the edge of the opening is denoted by 21 and the punched round disc with 27. At the next processing station, a pulling of the edge 21 is down, whereby the in FIG. 4 shown course 22 of the edge is achieved. The annular blank blanks 20 now move into another processing station, in which a film 25 is placed over the opening 26 of the lid 20 and fixed there by heat sealing, which in the FIGS. 5 and 6 is apparent. The metal foil 25 is provided in a known manner on its underside with a plastic layer. The required film blank 25 is usually punched out of a wide film web and placed over the central recess or cover opening of the annular disc and the film is pressed by heat sealing at the edge of the round recess of the part 20 under heat, so that the film 25th is sealed to the lid 20 by melting and subsequent cooling of the plastic layer. This is known and will not be explained here. At most, a cooling processing station can be provided for cooling. In another processing station, the film 25 with an embossment 24th ( FIG. 7 ), and it is further the edge 22 crimped to the finished edge 23. Different crimping forms can be provided.

The requirements that are placed on such container lid, correspond to those who are placed on conventional covers for sheet metal containers or other containers or packaging body. This includes corrosion resistance, not only against external influences, but especially against the contents, which is often chemically aggressive. Especially with moist or wet products corrosion is problematic in view of the long storage time, as required for packaging of the type mentioned. To prevent corrosion, the sheet metal from which the sheet metal covers or the cover rings made of sheet metal are coated coated. The coating of the sheet is known to the person skilled in the art; It usually consists of polyethylene terephthalate (PET) on the inner side of the container or a high-strength thermo-lacquer which is capable of crimping and also withstands aggressive products over the required storage period of sometimes several years. The outside is coated with polypropylene (PP) or a paint with PP particles, although such a coating is only reduced flanging (ie mechanically durable), since preferably PP is used as the adhesive or sealing medium of the tear-open, which in turn in sufficient quality only adheres to a PP coated surface. Both the PET and PP coatings have been tried and tested on an industrial scale.

The resulting in the formation of the lid opening 26 cutting edge 21, however, is no longer coated. A raw cut edge on the inside of the cover ring is at best not problematic with dry contents and short storage time; As a rule, however, corrosion is the result, which undesirably affects the contents and, for example, can affect the taste of food. This sequence is known to be encountered, in that the lid ring is provided on its inside with a curled edge area at the cutting edge, a so-called "retort-curl". As a result, the raw cut edge is covered by a surface region of the cover ring and is usually no longer accessible to the contents. Disadvantages of this solution are the comparatively high production costs, which occur in particular on the side of the tool. Above all, it is disadvantageous that the retort curl can not be produced today with the required high and uniform quality in a large series, in mass production. Only slight deviations in the production lead to the irregular formation of the retort curl in such a way that the cut edge is not reliably covered. Even a slight change in the cross section of the rolled-up wall section results in the cutting edge not resting continuously on the corresponding surface region of the cover ring, so that the filling material can reach the uncoated cut edge.

Out WO 01/07330 a solution has become known in which a cover ring is punched out of uncoated metal sheet. This has the consequence that the punched-out inner part, which of course is also uncoated, is easily reusable, which lowers the material costs of the correspondingly produced cover rings. The subsequent coating of the molded cover ring must be done as a powder coating, since the conventional, suitable for the coating of metal sheets methods are not applicable. On the one hand, this solution entails that the cut edge is also coated; However, it is disadvantageous that the powder coating of a geometrically complicated body, for example a cover ring, is difficult to achieve in the required quality and, accordingly, is only suitable for industrial use. Out WO 2006/092073 It is known to coat the cut edge separately with hotmelt material. EP-A-0 090 957 suggests the edge area to bend the lid opening to the outside of the lid, whereby the cutting edge comes to rest outside the Füllgutraumes of the container. But this complicates the application of the tear-off.

Presentation of the invention

It is an object of the present invention to avoid the disadvantages of containers with tear-open lids or tear-open lids.

This object is achieved with a container according to claim 1.

Since the cutting edge lies in the fastening region of the lid on the bottom of the container and thus lies adjacent to the upper edge of the lid, it is not exposed to contact with the contents of the container. The cut edge is thereby trapped between the coated hull and the coated lid. This results in easily manufacturable way to protect the cutting edge against corrosion.

Preferably, the lid is connected to the container sump by means of a fold. It is preferred that the cut edge lies with the unfolded fuselage inside, so that the cut edge does not come to lie in the actual folded area. This allows the production of the fold on conventional devices for forming the fold. In a further embodiment, the cut edge can be laid so far in the fold area that it lies in the hinge connection itself; In this case too, production with conventional or at most slightly modified folding tools may be possible. Preferably, the cut edge is covered by a mass, which is preferably the sealant of the rabbet joint. Preferably, the bending radius at the lid opening is greater than or equal to 1 mm. This chipping or chipping the coating of the cover ring can be safely avoided.

The invention is further based on the object to provide a Aufreissdeckel or a Aufreissdeckelring for the inventive container.

This is done with the features of claim 8 and of claim 10.

This results in a container provided with this lid of the described for the container advantage.

Furthermore, the invention relates to a method for producing a container with a tear-open lid or a tear-open lid. These methods are defined by the features of claims 11 and 13, respectively.

Brief description of the drawings

• Figur 1 eine perspektivische Ansicht eines Gebindes mit einem Aufreissdeckel;
• Figuren 2 bis 8 verschiedene Stadien der Herstellung von Aufreissdeckeln nach Stand der Technik;
• Figur 9 eine Ansicht des Deckelrandes;
• Figur 10 eine Ansicht einer Falzverbindung zwischen Deckel und Gebinderumpf;
• Figur 11 eine Ansicht einer Ausführungsform der Erfindung; und
• Figur 12 eine Ansicht einer weiteren Ausführungsform der Erfindung.

Further advantageous embodiments of the invention will become apparent from the dependent claims and from the embodiments illustrated below with reference to the drawings. Show it:

• FIG. 1 a perspective view of a container with a tear-open;
• FIGS. 2 to 8 various stages of manufacturing prior art tear-open lids;
• FIG. 9 a view of the lid edge;
• FIG. 10 a view of a rabbet joint between the lid and container sump;
• FIG. 11 a view of an embodiment of the invention; and
• FIG. 12 a view of another embodiment of the invention.

Ways to carry out the invention

Size relationships shown in the figures are shown purely by way of example and should not be interpreted as limiting. In the figures, like reference numerals designate structurally or functionally equivalent components. The geometry of the packaging or of the container, and thus of the lid, is not limited to round packaging bodies; oval, rectangular or other shapes are also possible. In the present case, such forms should always be included in the terms "container", "tear-open lid" and "tear-open lid ring". The term "tear-open ring" here refers to a carrier for a sealing film. The container sump may also be made of metal, but may also consist of another material, in particular of a material containing cardboard or of a layer material, such as cardboard and aluminum.

FIG. 1 shows a container 1 with a hull 4 and with a Aufreissdeckel 2, the lid opening is closed by the tear-open film 25. This is provided with a tab 28 for tearing the film from the lid ring. In the view of FIG. 1 is no difference of the container according to the prior art to a container according to the invention can be seen. The FIGS. 2 to 8 show the procedure of the prior art, which has already been explained above and which can also be provided as a preferred example of the formation of a tear-open lid or Aufreissdeckelringes invention, with the exception of the inventive aspect of the protection of the free cutting edge, in the inventive embodiments with the reference numeral 3 is designated. In this sense, reference is made to the formation of the tear-open on the above description of the prior art and this is taken over here. The container further comprises a bottom cover 5, which may be designed in particular as a metal floor attached by means of a fold on the hull.

The attachment of the tear-open lid 2 on the container can be done in any known manner, as far as it is compatible with the below-described protection of the cut edge. However, a rabbet connection of tear-open lid and container sump is preferred. FIG. 9 shows the formation of the container-side lid edge for the seam connection, and FIG. 10 shows a corresponding hinge connection of the lid and hull, as is known in the art.

In FIG. 9 is only a part of the lid 2 in cross section visible. This embodiment of the lid has, as in the Figures 2-8 , a folding edge 30 (seaming panel), which is on the cover outside with a curl 31 (curl) is provided. On the inside, a sealing compound 8 is provided at the seam edge. To the removal opening, not shown, the lid 2 has a seam radius 32 (seaming panel radius), with which the seam edge in the lid core wall 34 (chuck wall) merges, which core wall of the core depth radius 33 follows (chuck wall radius). The radii mentioned with the lid core wall give the lid core depth d (countersink depth). If such a cover 2 with the container sump, which is provided on the cover side with a flange (flange), connected by folding, the result is the connection according to FIG. 10 , The seam connection is made in a manner known to those skilled in the art, by a Verschliesskopf engages in the lid and on the outside successively different V-rollers make the fold. The finished compound according to FIG. 10 in which the same reference numerals as in FIG. 9 denote like elements, takes place in that a folded body hook 37 (body hook) with the lid hook 38 (endhook) is engaged. This results in a stable connection between the cover 2 and the fuselage 4, wherein the cover core wall 34, as shown, can rest against the fuselage inner side 7. The mentioned sealant 8 (lining compound) seals the seam connection.

FIG. 11 Now shows a preferred embodiment of the inventive container 1 or Aufreissdeckels 2 or Aufreissdeckelringes. Again, a part of the container and the lid is shown. It is apparent that unlike the lid of the 20 characters 2-8 According to the prior art, the cutting edge 3 of the lid is guided into the fastening region of the lid 2 on the fuselage 4. This is shown for the preferred embodiment as a rabbet joint. The connection between the cover 2 and the fuselage 4 could, however, also be carried out in a purely mechanical manner by positive locking and / or frictional engagement or gluing or hot-sealing or a combination of such fastening types in other ways. It is essential in each case that the cutting edge 3 is returned to the fastening region, so that it is completely enclosed in particular by the lid 2 and the inner side of the fuselage 7, in particular with respect to the filling material. This inclusion can be improved by a sealant, an adhesive, or a hot sealant. Primarily, the protection of the cutting edge 3 but done by returning to the mounting area. FIG. 11 shows a greatly enlarged representation. With a lid diameter of about 50 mm, the length of the bent-back part from the lid opening or removal opening 26 into the fastening or folding area 6 is eg 7.8 mm. Of course, these figures are to be considered as an example only. It can be seen that in this preferred example, the cutting edge 3 rests with its one corner on the inside of the fuselage 7 and is acted upon by the core wall 34 on the other side of the cutting edge 3, so that a complete protection of the cutting edge 3 results. This is guided by the return in the mounting portion 6 up to the seaming edge 30, but not involved in this example in the actual Falzverbindung with fuselage hook and lid hook. In another embodiment, the cutting edge 3 could be guided over the trunk hook radius 30, so that the cutting edge 3 is retracted into the fold 6. Preferably, the in FIG. 11 Sealant 8 not shown provided such that it reaches the cutting edge 3 and this also covers.

Subsequently to the removal opening 26 there is a flange 40, directly adjacent to the bending edge 13, which is formed from the double sheet material 41 and 42 of the lid 2. This embodiment, which results from returning the cut edge into the fastening region 6, is advantageous for the sealing of the tear-open film 25, since more heat energy can be introduced into the double flange, particularly in the case of heating by induction. Since there is usually a polypropylene coating due to the return on the underside of the flange, attention must be paid to the design of the lower heat sealing head, in which this e.g. with a non-stick coating to prevent sticking to the sealable polypropylene coating.

FIG. 12 shows a further embodiment in which the bend 43 is carried out at the edge of the lid opening 26 with a radius R, which is preferably greater than about 1 mm. In this way, splintering of the PP coating during bending is reliably avoided.

Claims (13)

1. Container (1) with a container body (4) and a tear-open lid (2, 28) with a tear-open lid ring of metal, which forms the extraction opening (26) of the container, and a tear-open foil (25) which closes the extraction opening (26) of the tear-open lid, characterized in that the cut edge (3) resulting during the punching of the tear-open lid ring for forming the extraction opening (26) lies in the attachment area (6) of the lid at the container body (4) and is enclosed between the coated container body and the coated tear-open lid.
2. Container according to claim 1, characterized in that the tear-open lid (2) is attached at the container body (4) by means of a folding seam attachment (6).
3. Container according to claim 1 or 2, characterized in that the cut edge (3) lies at the inner side (7) of the body.
4. Container according to one of the claims 1 to 3, characterized in that the cut edge (3) lies between the inner side (7) of the body and the chuck wall (34) of the lid.
5. Container according to claim 2, characterized in that the cut edge lies in the folding seam attachment (6).
6. Container according to one of the claims 1 to 5, characterized in that the cut edge (3) is covered by a mass (8) which is preferably the lining compound of a folding attachment of the tear-open lid with the container body.
7. Container according to one of the claims 1 to 6, characterized in that the folding radius of the lid edge (43) is higher than or equal to 1 millimetre at the extraction opening (26).
8. Tear-open lid (2) for a container according to one of the claims 1 to 7, characterized in that the cut edge (3) is led back into the area of the chuck wall (34) of the lid, such that, in accordance with the intended attachment of the tear-open lid at the container body (4) of a container in the attachment area (6), the cut edge (3) comes to lie at the container body (4) and is enclosable between the coated container body and the coated tear-open lid.
9. Tear-open lid according to claim 8, characterized in that the folding radius of the folding edge (43) is higher than or equal to 1 mm at the extraction opening (26).
10. Tear-open lid ring (2) for a tear-open lid according to one of the claims 8 or 9, characterized in that the cut edge (3) is led into the area of the chuck wall (34) of the lid, such that, in accordance with the intended attachment of the tear-open lid at the container body (4) of a container in the attachment area (6) of the tear-open lid, the cut edge (3) comes to lie at the container body (4) and is enclosable between the coated container body and the coated tear-open lid.
11. Method for manufacturing a container (1) with a tear-open lid (2), having a tear-open lid ring forming the extraction opening (26) of the container, characterized in that the forming of the extraction opening (26) for the tear-open lid is done in such a way that a double flange (40, 41, 42) is formed during the folding of the cut edge (3) of the extraction opening formed during the punching of the tear-open lid ring for the forming of the extraction opening and the cut edge is lead into the area of the chuck wall (34) of the lid, and in that the tear-open lid is attached to the container body (4) by means of a fold seam attachment (6), wherein the cut edge is received between the chuck wall (34) of the lid and the inner side (7) of the body.
12. Method according to claim 11, characterized in that the lining compound (8) of the fold seam attachment is provided in such a way that it covers the cut edge (3).
13. Method for manufacturing a tear-open lid (2) or a tear-open lid ring of metal, characterized in that the forming of the extraction opening (26) for the tear-open lid or the tear-open lid ring respectively is done in such a way that a double flange (40, 41, 42) is formed during the folding of the cut edge (3) of the extraction opening which is formed during the punching of the tear-open lid ring for the forming of the extraction opening and the cut edge (3) is lead into the area of the chuck wall (34) of the lid, such that, in accordance with the intended attachment of the tear-open lid at the container body (4) of a container in the attachment area (6), the cut edge (3) comes to lie at the container body (4) and is enclosable between the coated container body and the coated tear-open lid.

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