EP3880574B1 - Captive closure with stabilized opening angle - Google Patents

Description

The present invention relates to a captive closure, comprising a screw cap with a guarantee band, which has at least one cylindrical cap shell with an internal thread and a circumferential guarantee band at the lower, open end of the cap shell, which is connected to the lower edge of the cap shell along easily tearable weakening lines, wherein the guarantee band remains permanently connected to the cap shell via retaining bands after tearing along the weakening lines, wherein the closure is designed for use on an opening nozzle of a cardboard packaging, wherein the closure has a lower closure part with a circumferential flange, which can be connected in a sealed manner to the surface of a cardboard packaging, and a cylindrical pouring spout adjoining the flange, which has an upper outer and a lower inner opening, wherein the closure is further equipped with the screw cap with the internal thread, which can be screwed onto an external thread of the pouring spout, a cutting ring arranged in the pouring spout, which has at least one cutting edge projecting axially inwards on its lower edge, and a axial lifting and driving device on the cutting ring and the screw cap, which comprises a driver attached to the inside of the screw cap and an axial lifting device which, when the screw cap is rotated in the opening direction, moves the cutting ring axially in the direction of the lower opening and in the circumferential direction and thereby makes an at least partially circular cut in the container surface.

Plastic products and corresponding plastic waste, especially in the form of so-called microplastics, which are formed from plastic waste through abrasion and decomposition, are increasingly the focus of public attention. The screw caps to which the present invention relates are also made of plastic, typically polyethylene or polypropylene.

The deposit system, which has also been introduced for disposable plastic bottles, does indeed reduce the number of plastic bottles that end up in residual waste and are instead recycled; however, this does not prevent the fact that in many cases the bottle caps are not screwed back on after emptying, but are disposed of separately or thrown away, thus ending up in the environment in an uncontrolled manner and, for example, in the sea on shores and beaches.

There have been and are efforts to design closures on containers, especially on beverage containers and beverage cartons, in such a way that they remain connected to the container neck even after a container has been opened. Such a property is also referred to as "captive".

Captive closures are known in principle.

From the European patent application EP 1 533 240 A1 is a resealable closure for a sealed cardboard packaging.

Particularly in the case of disposable containers, the so-called guarantee bands, which are connected to the lower edge of a cap jacket via weak points, remain attached to the container neck below a so-called pilferproof ring and already form a captive part of the closure. In this respect, it is only necessary to ensure that the screw cap remains connected to the guarantee band via at least one band section or the like, referred to here as a retaining band, even after the screw cap has been opened and released from the container neck thread. This band is in turn held on the container neck by the so-called pilferproof ring. A pilferproof ring is typically an annular projection running all the way underneath a container neck thread with an essentially flat or slightly conical underside, behind which radially inwardly projecting projections or parts of a guarantee band hook, so that the guarantee band is held in place by the pilferproof ring when a screw cap is unscrewed, while the weak points provided between the guarantee band and the cap jacket tear.

All that is then required is to ensure that the connection between the guarantee band and the cap jacket, which remains via at least one retaining band, is long enough to be able to lift the screw cap completely off the container neck opening and to move it sideways or tilt it away from the container neck opening.

However, these captive screw caps have often proven to be very annoying in use, as the caps move back in front of the opening of the container when pouring liquid from a corresponding container, for example, or twist under the effect of gravity on the container neck and get into the liquid stream when pouring.

Particularly when a user wants to drink directly from a container, screw caps that are still attached to the container neck are often in the way and annoying. Conventional captive closures can also cause problems when closing containers in high-performance closing systems.

Against this background, the present invention is based on the task of designing a captive screw cap with a guarantee band for use on an opening nozzle of a cardboard packaging in such a way that the screw cap, after being unscrewed and loosened, can be folded away or tilted into a position that does not interfere with further use of the cardboard packaging and drinking or pouring from the cardboard packaging and can remain there without additional measures. The screw cap is also referred to here as "cap" for short.

This object is achieved by a closure according to the present invention as defined in claim 1.

In the screw cap according to the invention, retaining bands are formed by two weakening lines, each interrupted at least once in the circumferential direction, which run at an axial distance from one another and partially overlap each other in the circumferential direction, with interrupted sections of both weakening lines being bridged by the other weakening line at an axial distance. The weakening lines can be produced by cuts or by dividing lines with webs already formed in the injection molding tool.

The aforementioned interrupted sections of the weakening lines are referred to below as "separating webs". The separating web of the upper weakening line effectively forms an axial extension of the cylindrical cap shell that is limited to a circumferential sector. The separating web of the lower weakening line forms an axial extension of a lower guarantee band section that is held stationary on the lower part of the closure.

In the case of conventional closures in which the guarantee band and the cap jacket are connected to one another along a single, circumferential line of weakness which tears open when the cap is opened for the first time, the term "guarantee band" refers to all sections on the lower edge of a closure cap jacket which lie axially below or beyond the level of the line of weakness from the cap thread, which corresponds to the line referred to here as the upper line of weakness.

"Axially below" here also includes the inward and upward angled section of a so-called flex band, which, when manufacturing the closure cap, has an axial extension of the outer guarantee band section, even if parts of this angled flexible band section, when folded upwards, can extend on the inside of the cap above the level of the upper weakening line.

To simplify the description, the above definition of the term "guarantee band" is retained here, i.e. both separating strips are considered to be part of the guarantee band as long as they are below the level of the upper weakening line, even if the separating strip of the upper weakening line remains firmly connected to the lower edge of the cap jacket and only detaches along the lower weakening line from the parts of the guarantee band that remain stationary on the lower part of the closure. This also applies analogously to the retaining bands, which are also below the level of the upper weakening line when the closure is closed, but do not remain in this position during and after opening.

The guarantee band thus defined consists of a part which remains stationary on the closure base and which - apart from rotation - remains immovable relative to the closure base, and of movable parts, such as the retaining bands and the upper separating web, which are movable relative to the stationary part and the closure base when opened, but remain connected to the stationary part.

In this way, the entire closure remains permanently connected to the lower part of the closure.

The separating webs have ends in the circumferential direction, which are each connected to one of the ends of the retaining bands across their axial width. The separating webs have at least the same inner radius as the cap shell. The free end face of the upper separating web pointing axially downwards is referred to as the lower edge, while the axial end region of the upper separating web that encompasses the edge is referred to as the "rim".

The sections of the weakening lines that overlap in the circumferential direction define the retaining bands as strip-shaped sections of the guarantee band that run between the weakening lines in the circumferential direction.

The cylindrical cap shell with internal thread defines an axis of the closure, and the closure base, onto which a corresponding screw cap is screwed, defines an axis of the closure base. When closed, these axes coincide.

A sufficient axial distance between the weakening lines of, for example, at least 2 mm in their overlap area leads to sufficiently strong retaining straps that do not tear up to a tensile force of 30 N and generally up to 40 N. For an average consumer and it is therefore not possible for children in particular to tear the screw cap off the part of the guarantee band held under the pilferproof ring by tearing the retaining bands. This means that the cap, including the guarantee band, remains permanently connected to the lower part of the closure.

By appropriately coordinating the circumferential extent of the separating webs and the distance of the weakening lines (measured in the axial direction), it is possible to ensure that a screw cap, after being unscrewed and lifted off and folded over, is brought into a sufficiently stable position at a sufficient distance from the container neck opening, in which position it remains after opening and folding over and, regardless of the orientation of the associated container neck, does not end up in a disturbing position in front of the closure base mouth due to its own weight.

Each of the two weakening lines expediently has exactly one separating web and the centers of the two separating webs are diametrically opposite each other. The weakening lines are at an axial distance from each other in their overlapping areas. In one embodiment, the two weakening lines remain in the same axial position along their entire circumferential extent in the unopened closure, but the axial position between the two weakening lines is different. The axial position of the weakening lines can, however, also vary along their course in the circumferential direction, as long as this does not make the retaining bands too narrow and they retain a sufficient tear resistance of at least 30 N to preferably at least 40 N.

In the separating webs of the weakening lines, such an axial distance is not important and the other weakening line which is not interrupted there could, in this area, change to an axial position which otherwise corresponds to the interrupted weakening line or has an even greater axial distance from it.

The upper weakening line defines a dividing line between the lower edge of the cap jacket and the tamper evident band. The lower weakening line divides the tamper evident band along a circumferential section into a lower and an upper tamper evident band section, whereby the upper tamper evident band section is firmly connected to the cap jacket in the area of the interruption of the upper weakening line and otherwise defines a section of the dividing line between the retaining bands and the lower tamper evident band section.

In one embodiment, the guarantee band is a so-called flexible band, which has a first outer guarantee band part running in axial extension of the cylindrical cap shell and a second guarantee band part running radially inwards and towards The guarantee band part is folded over at the top and the free, upward-facing end of the guarantee band has engagement elements for engagement with the underside of the pilferproof ring.

The terms "top" and "bottom" are used here as they arise when the closure is oriented onto the container neck opening of a vertically standing container.

The separation of the guarantee band along the entire length of the weakening lines results in strip-shaped sections of the guarantee band being created in the overlapping area of the weakening lines due to their axial distance, which are referred to here as retaining bands. These retaining bands connect the respective separating webs of the upper and lower weakening lines, whereby these separating webs in turn form a connection to the cap jacket or to the first guarantee band part, which is intended to remain stationary on a closure bottom part. The separating web of the lower weakening line is a determining factor for the length of the retaining bands, but has no other function with regard to the stability of the open cap position. The separating web of the upper weakening line (upper separating web), on the other hand, contributes significantly to stabilizing a wide-open state of the cap, depending on its design. Where the "separating web" is mentioned below without further identification, this upper separating web is always meant. This separating web forms an axial extension of the cap shell and is firmly connected to it.

The ends of this separating web in the circumferential direction are each connected to one of the ends of the retaining straps. The other end of the retaining straps is each connected to the ends of the lower separating web in the circumferential direction

After unscrewing and then folding away or over the screw cap, which remains connected to the lower part of the closure via the separating bars and the retaining straps, the cap, after a pivoting movement of approx. 90 °, comes into a position in which the lower edge of the separating bar pivoted with the cap is moved radially inwards towards the lower part of the closure and the upper edge of the separating bar, immediately adjacent to the cap jacket, is moved radially outwards away from the lower part of the closure.

The retaining straps between the two separating bars are twisted and hold the cap, or the separating bar that axially extends the cap, in contact with the lower part of the closure. The lower edge of the separating bar or its lower edge is in contact with the lower part of the closure and forms a pivot point on the lower part of the closure, which, however, moves in the axial direction during the pivoting movement on the lower part of the closure. Apart from a slight restoring force of the twisted retaining bands, the guarantee band initially does not offer any significant resistance during the folding movement of the screw cap and the radial pivoting of the lower edge of the separating strip towards the lower part of the closure.

As the retaining straps are connected to the ends of the divider across their entire width, the sections of the retaining straps immediately at the upper end of the divider are stretched slightly more than the sections at the lower end of the divider. The axial height of the divider between the pivot point and the upper attachment of the retaining straps therefore forms a lever for the pulling force of the retaining straps, which assists the further opening movement of the cap when the pivoting movement passes the dead center at approx. 90°. This allows the cap to reach a stable opening angle of e.g. 140° compared to its initial position. In addition, due to the upward movement of the screw cap, the retaining straps extend over the pilferproof ring with the upper divider, which contributes to the stretching and tensile stress in the retaining straps. The fact that the divider extends over a certain circumferential angle of e.g. B. 20 - 60°, leads to an increase in the distance between the ends of the separating bar and the lower part of the closure when the cap is folded over due to the curved course of the separating bar along the circumference and with the radius of the cap jacket and thus to a corresponding increase in the tensile force in the retaining straps, which thus hold the cap in the wide open position by pulling the folded-over separating bar towards the lower part of the closure.

Basically, however, the retaining bands, i.e. the length of the overlapping areas of the two weakening lines, and also the axial height and circumferential length of the separating web are designed in such a way that the stretching of the bands remains in the elastic range and does not reach the yield point.

This means that the engagement between the lower edge of the separating bar and the lower part of the closure by the retaining bands exerts a varying force on the separating bar, which initially increases when the screw cap is tilted, then passes a dead center and then decreases again when the screw cap and with it the upper separating bar are tilted by more than about 90° compared to their closed position, whereby the retaining bands extending between the two separating bars are twisted. Due to a comparatively low wall thickness of, for example, 0.3 to 0.6 or 0.8 mm and a moderate width (measured in the axial direction) of the retaining bands of, for example, 3 mm, the elastic restoring forces due to the torsion of these retaining bands are relatively low compared to the force which the retaining bands exert on the upper separating bar in the direction of the lower part of the closure.

As a result, the folded-over position of the closure, reached after overcoming a dead center, remains essentially stable and the screw cap does not move in a disturbing manner in front of or too close to the opening of the lower part of the closure.

In order to ensure that the screw cap does not cause interference, especially when drinking, in one embodiment the axis of the closure cap, which coincides with the axis of the closure base when the closure is closed, should assume a stable position after opening and folding to the side, in which it is pivoted by at least 120 degrees, preferably by at least 140°, relative to the starting position or relative to the axis of the closure base.

In view of the way the captive closure functions during and after the screw cap is folded over, it becomes clear that the specific restoring and stabilising forces generated depend on a whole series of interacting parameters, including a certain axial width and the circumferential extent of the upper separating strip fixed to the cap jacket, the difference between the outer radius of the closure base and the inner radius of the separating strip, which corresponds to the inner radius of the cap, and the circumferential extent of the weakening lines and the lower separating strip (and thus the length of the retaining straps).

The aforementioned parameters can be adjusted in different combinations so that the folding movement of the screw cap takes place over a dead center, so that the screw cap has a bistable position overall, whereby the screw cap in the fully open, stable position does not impede access to the closure base opening. Preferred and practically functional values for the above parameters are given below and in the dependent patent claims.

In principle, it is advisable, although not essential, for each line of weakness to have exactly one separating strip and for the centre points of the separating strips to be diametrically opposite one another. The separating strip of the lower line of weakness, which is firmly connected to the rest of the guarantee band, limits the overlap between the upper and lower lines of weakness in one direction and the overlap of the lines of weakness determines the length of the retaining strips that connect the guarantee band remaining on the lower part of the closure to the screw cap casing.

The separating bar of the upper weakening line expediently extends over a circumferential angle between 10° and 75°, preferably in the range between 20" and 60°. An angle in this range ensures that the separating bar is stable in itself and is folded over together with the cap jacket and that when opened not only the cap jacket is bent over against the separating bar, and on the other hand this also ensures sufficient force, which holds the folded-over closure in its fully open position, for which the divider must have a certain minimum length in the circumferential direction.

The separating web of the lower weakening line, which is diametrically opposite the separating web of the upper weakening line, can extend over a circumferential angle between e.g. 120° and 200°, preferably between 170° and 190°, wherein the difference between the circumferential angles of the upper and lower separating webs defines the length of the retaining bands which extend between the remaining part of the guarantee band and the cap jacket.

The width of the separating strip remaining on the cap jacket should preferably be at least half the width of the entire intact guarantee strip, i.e. not yet separated along the weakening lines, so that the torsion of this relatively wide section compared to the rest of the guarantee strip causes a corresponding difference in diameter and length between the radially inner, lower edge of the separating strip and the upper edge of the separating strip attached to the screw cap.

Expressed in figures, the width (in the intact state) measured in the axial direction of the separating web remaining on the cap jacket should be at least 1.5 mm, preferably at least 2 mm and in particular about 3 mm or more. The wall thickness of the guarantee band, on the other hand, is in a range between 0.3 and 0.8 mm, so it is clear that the forces caused in the band by twisting the separating web relative to the rest of the band are caused, among other things, by the different inner and outer radii of the twisted guarantee band sections (consisting of the retaining bands and the upper separating web), which is greater the wider the twisted section is.

The minimum width of the retaining straps measured in the axial direction depends, among other things, on the specific plastic material used and also on the wall thickness of the retaining straps. The minimum distance between the weakening lines, which defines the minimum width of the retaining straps, should therefore be greater than 1 mm, preferably greater than 2 mm and in particular greater than 2.3 mm in one embodiment. An upper limit is determined in each case by the width of the guarantee strip. The retaining straps, which are effectively formed as the sections of the guarantee strip running between the dividing lines, then have sufficient tear resistance to prevent the screw cap from being forcibly torn off the guarantee strip - at least by children's hands. The retaining straps are preferably tear-resistant up to a tensile force of at least 30 N, preferably at least 40 N.

The combination according to the invention of a closure base with an external thread and a closure, as described above, is characterized in that the external diameter of the closure base above a pilfer-proof ring, the internal diameter of the guarantee band, as well as the width, the circumferential extent and any thickening of the upper separating strip are coordinated with one another in such a way that after loosening and when the screw cap is subsequently folded over, the free lower edge of the separating strip engages with the closure base. The retaining strips are twisted slightly in the process. When a tilt angle of approx. 90° is exceeded, the cap with the separating strip is moved past a dead center so that the outside of the separating strip then faces the outside of the closure base and the screw cap is stabilized in this position folded over by more than 90° due to a certain tension of the retaining strips.

The tilt or folding angle is defined here as the angle between the axis of the shutter base (which coincides with the shutter axis when the shutter base is closed by the shutter) and the shutter axis in the folded state.

The difference between the outer diameter of the lower part of the closure in an area above the pilferproof ring, in which the upper separating bar of the guarantee band is arranged on the lower part of the closure after the closure has been opened, should be no more than 2.5 mm, preferably no more than 1.5 mm, smaller than the nominal inner diameter of the guarantee band. The "nominal inner diameter" refers to the inner diameter of the guarantee band without any flexible band section, which in particular also corresponds to the inner diameter of the cap in the area of the upper separating bar before the weakening lines are cut open.

The axial dimensions of all parts below the cap jacket that traditionally form a tamper-evident band are in practice limited to a total of around 5 to 6 mm. The requirement to save material places an upper limit on this axial dimension. The lower limit on this dimension is sufficient functional stability. On the one hand, a tamper-evident band must be secured to the closure base in such a way that it is practically impossible to remove it from the closure base without damage. On the other hand, it must also withstand the forces when the closure is placed on a thread, particularly when it is moved over the pilfer-proof ring. These conditions can no longer be met if essential parts of the tamper-evident band are axially shorter than, for example, 2 mm (apart from easily breakable bridges that may be distributed along a line of weakness).

If, as in the present case, the closure part below the cap jacket is additionally divided into the elements stationary part, retaining straps and separating bars, there is little scope for variation of the axial width of the retaining straps and the axial height of the separating bars available. In practice, both dimensions are in the range of 2 - 3 mm. In the peripheral area of the retaining bands and the upper separating web, an axial width of about 2 - 3 mm remains for the stationary outer guarantee band section. Any axial variation in the course of the weakening lines along their peripheral extension would therefore also be limited to an axial area of a maximum width of 1 mm for practical reasons. This would not change the basic function of a closure according to the invention and is therefore not discussed in detail here.

In one embodiment of the invention, the stationary part forms a flexible band with the outer stationary section already described and a part folded inwards and upwards, which engages with the pilfer-proof ring of a closure lower part.

According to the invention, the closure is designed for use on an opening nozzle of a cardboard packaging.

Such a screw cap for cardboard packaging has a lower part of the cap with a circumferential flange that can be connected to the surface of a cardboard packaging in a sealed manner, as well as a cylindrical pouring spout connected to the flange, which has an upper outer opening and a lower inner opening, a screw cap with an internal thread that can be screwed onto an external thread of the pouring spout, a cutting ring arranged in the pouring spout, which has at least one cutting edge projecting axially inwards on its lower edge, and an axial lifting and driving device on the cutting ring and the screw cap, which comprises a driver attached to the inside of the screw cap and an axial lifting device which, when the screw cap is rotated in the opening direction, moves the cutting ring axially in the direction of the lower opening and in the circumferential direction and thereby creates an at least partially circular circumferential cut in the container surface.

The problem underlying the invention is solved in that the screw cap has a circumferential guarantee band on the lower edge of its cap jacket, which with an inner projection engages behind a pilfer-proof ring on the outside of the pouring spout below the pouring thread, wherein the guarantee band is partially divided and partially separated from the jacket of the screw cap by two separate, partially circumferential and circumferentially partially overlapping and non-intersecting weakening lines, so that in the circumferentially overlapping areas of the weakening lines, a retaining band is formed from parts of the guarantee band, which holds the screw cap released from the external thread to the lower part of the guarantee band that remains divided at the closure.

In the closure, the cutting ring has on its outside a second external thread that runs in the opposite direction to the external thread of the pouring spout and that engages with a matching second internal thread on the inside of the pouring spout.

In the closure, the second internal thread and the second external thread can have a larger pitch than the internal thread of the screw cap and the external thread of the pouring spout, wherein the factor between the different pitches is preferably at least 1.5

Furthermore, the driver of the screw cap can be designed as a lifting cam with a surface or edge inclined to the closure axis and an element of the cutting ring can be designed as a cam follower, and radially overlapping guide elements can be provided on the outside of the cutting ring and on the inside of the pouring spout, wherein the guide elements only allow an axial movement of the cutting ring at the beginning of an opening rotation of the screw cap and only allow the cutting ring to be driven in the circumferential direction after a predeterminable axial position of the cutting ring has been reached and limit the further axial movement,

Figur 1

eine perspektivische Ansicht eines Verschlusses

Figur 2

den Verschluss nach Figur 1 in einer Seitenansicht,

Figur 3

eine 360°-Abwicklung des Garantiebandes des Verschlusses aus Figur 2,

Figur 4

einen axialen Schnitt durch einen erfindungsgemäßen Verschluss für Getränkekartons,

Figur 5

den Verschluss nach Figur 4 in einer Ansicht von außen im geschlossenen Zustand,

Figur 6

den geschlossenen Verschluss nach Figur 4 in einer Ansicht von oben.

Figur 7

den Verschluss nach Figur 4 in einem teilweise geöffneten Zustand und

Figur 8

einen vollständig geöffneten Verschluss gemäß Figur 4 mit einer umgeklappten Schraubkappe.

Further advantages, features and possible applications of the present invention will become clear from the following description of a preferred embodiment and the associated figures. They show:

Figure 1

a perspective view of a closure

Figure 2

the closure after Figure 1 in a side view,

Figure 3

a 360° unwinding of the guarantee band of the closure made of Figure 2 ,

Figure 4

an axial section through a closure according to the invention for beverage cartons,

Figure 5

the closure after Figure 4 in a view from the outside in the closed state,

Figure 6

the closed shutter after Figure 4 in a view from above.

Figure 7

the closure after Figure 4 in a partially opened state and

Figure 8

a fully opened shutter according to Figure 4 with a folded screw cap.

The Figures 1, 2 and 3 The embodiment shown and described below is not according to the invention and serves only for illustration purposes.

According to the perspective view in Figure 1 the closure shown there consists of a screw cap 10 with a guarantee band, whereby the screw cap 10 essentially consists of a cap shell 2 and a head plate 1, which pushes the cylindrical cap shell 2 upwards At the lower end of the cap jacket 2 there is a guarantee band 3 which cannot be completely separated from the screw cap 10 in the closure according to the invention.

Conventional screw caps with a guarantee band have only a single line of weakness, which, unlike the line of weakness 13 shown here, runs without interruption along the entire circumference of the screw cap 10 and represents the dividing line between the screw cap 10 and the guarantee band 3.

A line of weakness can generally be a circumferential, uniform weakening of the material, which can be created, for example, by an incision that does not completely penetrate the material of the guarantee band 3 or the transition to the cap jacket 2, or it is an incision that completely penetrates the wall thickness of the guarantee band 3, but which is interrupted at individual points by easily breakable bridges.

The closure shown differs from this usual form of screw caps with a guarantee band in that it has two weakening lines 13, 14 which, on the one hand, are spaced apart from one another in the axial direction and, on the other hand, do not extend over the entire circumference of the guarantee band, but are interrupted in an upper separating web 11 of the upper weakening line 13 and in a lower separating web 12 of the lower weakening line 14.

The Figure 2 is a side view of the closure from Figure 1 to recognize and Figure 3 shows a development of the guarantee strip 3 over 360°, ie the ends of the guarantee strip shown on the right and left at 0° and 360° respectively abut one another and are connected so that the guarantee strip as a whole has a ring shape. The separation in this development representation divides the separating web 12 into two parts, although it is actually a single, connected separating web.

The interruption lines 13,14 are of different lengths, but are arranged in such a way that they overlap the dividing web 11 or 12 of the other weakening line. It is expedient if the centres of the dividing webs 11, 12 are diametrically opposite one another, as in the present case at 0° and 180° in Figure 3 .

If, after opening or unscrewing the screw cap from a container neck, the weak connection initially still existing along the weakening lines 13, 14 is completely severed, the retaining bands 15, 16 formed in the overlapping area of the weakening line form a substantially tear-resistant connection between the interruption areas 11, 12.

The interruption area 11 is connected to the lower edge of the screw cap and the interruption area 12 is connected to the part of the guarantee band 3 remaining in its original position, which is located below the weakening line 14.

The part of the guarantee band 3 remaining below the weakening line 14, together with the interruption area 12, forms a completely circumferential fastening band between the screw cap and the neck of the container, which is in engagement with a container neck. The interruption areas 12 and 11 are each connected to one another by remaining retaining bands 15, 16, which are created by the overlapping sections of the two weakening lines 13, 14, so that the screw cap 10 effectively remains connected to the lower section of the guarantee band and thus to the container neck via the retaining bands 15, 16 and is therefore undetachable.

The Figures 4 - 8 each show the same embodiment of a closure according to the invention for cardboard packaging, in particular drinks cartons, and are therefore described in conjunction with one another. A closure lower part can be seen, which is designated overall by 40 and consists of a flange 31 with a pouring spout 32 attached to it. The pouring spout 32 has an upper opening and a lower opening, not visible here, which, when the closure is on a cardboard packaging, is initially closed by the surface of the cardboard material in order to prevent any contamination of the container contents.

The flange 31 is glued or welded onto a cardboard box, whereby welding requires that the cardboard material is provided with a suitable surface coating (e.g. polyethylene).

The lower part 40 of the closure has an external thread 42 onto which the internal thread 41 of a screw cap 10 can be screwed.

The pouring spout 40 also has a further internal thread, into which a matching external thread of a cutting ring 35 engages, which also has axially projecting and in the closed state according to Figure 4 has cutting elements 33 lying directly above the surface of the carton. A driver 44 engages with a matching counterpart 36 on the cutting ring 35 when the screw cap is turned in the opening direction. A fixing web 7 can also be seen on the flange, which is connected to the lower end of the guarantee band 30 via two easily breakable bridges 6. The guarantee band has, as can best be seen in Figure 5 recognizes two weakening lines 13, 14 designed as cutting lines, which are defined either by weakened material of the guarantee band 30 or, as in the present case, by continuous incisions that are only interrupted by further easily breakable bridges which tear open when the screw cap is opened. The lower weakening line 14 and the upper weakening line 13 overlap each other, in the present case along a circumferential angle of approximately 120°, and each have a lower interruption section 12 and an upper interruption section 11. When the screw cap 10 is unscrewed, the easily breakable bridges 6 tear first and very quickly, which indicates that the closure has been rotated at least once by a small angle in the opening direction, which may be sufficient for the cutting elements to pierce the cardboard material.

When the screw cap 10 is rotated further in the opening direction, the easily breakable bridges of the weakening lines also tear, but this does not lead to a complete separation of the screw cap from the guarantee band, since the upper interruption section 11 remains connected via the holding bands 15, 16 (only one of each visible in the figures) to the lower interruption section 12, which in turn remains connected to the circumferential, stationary lower part of the guarantee band 30, which in turn is held in place by the pilfer-proof ring 35a on the lower closure part 40.

The length of the retaining straps 15,16, ie the length of the overlapping areas of the weakening lines is according to Figure 4 adjusted so that the lower edge of the upper interruption section 11, when the screw cap 20 is open and folded over by approximately 150°, engages with the outside of the pouring spout 32 and the retaining straps 15, 16 are under tension, so that this position of the screw cap is held by the tension of the retaining straps and the contact of the lower edge of the interruption section 11 with the screw cap 10, even if the pouring spout 32 is tilted in any direction together with the corresponding container.

List of reference symbols

1

Headstock

2

Cap coat

3

Guarantee band

6

easily breakable bridges

7

Fixing bar

10

Screw cap

11,12

Dividers

13,14

Lines of weakness

15,16

Retaining straps

30

Guarantee band

31

flange

32

Pouring spout

33

Cutting element

35

Cutting ring

35a

Pilferproofring

36

Counterpart on the cutting ring

40

Closure bottom part

41

inner thread

42

External thread

44

Driver

50

Axis of the container neck

Claims (11)

1. A closure comprising a screw cap (10) with a guarantee band (30), which has at least one cylindrical cap skirt (2) with an internal thread (41) and a circumferential guarantee band (3) at the lower, open end of the cap skirt (2), which is connected to the lower rim of the cap skirt along easily tearable weakening lines (13, 14), wherein the guarantee band (30), after tearing along the weakening lines, remains non-detachably connected to the cap skirt (2) via holding bands (15, 16), wherein the closure is designed for use on an opening connection piece of a carton package, wherein the closure has a closure base (40) with a circumferential flange (31) which can be connected in a sealed manner to the surface of a carton package, and a cylindrical pouring spout (32) which adjoins the flange and has an upper outer opening and a lower inner opening, wherein the closure is further equipped with the screw cap with the internal thread which can be screwed onto an external thread (42) of the pouring spout wherein the closure is provided with a cutting ring (35) arranged in the pouring spout and having at least one axially inwardly projecting cutting edge (33) at its lower rim, wherein the closure is provided with an axial lifting and entraining device on the cutting ring and the screw cap, which comprises an entraining element (44) attached to the inside of the screw cap and an axial lifting device which, when the screw cap is rotated in the opening direction, moves the cutting ring axially in the direction of the lower opening and in the circumferential direction and thereby introduces an at least partially circular circumferential cut into the container surface, characterised in that the holding bands (15, 16) are formed by two weakening lines (13, 14) which are each interrupted at least once in the circumferential direction, partially overlap in the circumferential direction and extend at least in the overlap region at an axial distance from one another, wherein the separating webs (11, 12) of both weakening lines (13, 14) are bridged by the respective other weakening line (14, 13) at an axial distance.
2. Closure according to claim 1, characterised in that each weakening line has exactly one separating web and the centres of the separating webs (11, 12) are diametrically opposite one another.
3. Closure according to one of the preceding claims, characterised in that the separating web (11) of the upper weakening line (13) extends over a circumferential angle of between 10° and 75°, preferably between 20° and 60°.
4. Closure according to one of the preceding claims, characterised in that the separating web (12) of the lower weakening line (14) extends over a circumferential angle of between 120° and 200°, preferably between 170° and 190°.
5. Closure according to one of the preceding claims, characterised in that the width, measured in the axial direction, of the upper separating web (11) remaining on the cap skirt (2) is at least half the width of the intact guarantee band (30).
6. Closure according to one of the preceding claims, characterised in that the width, measured in the axial direction, of the upper separating web (11) remaining on the cap skirt (2) is at least 1.5 mm, preferably at least 2 mm, in particular at least 2.5 mm and less than 5 mm.
7. Closure according to one of the preceding claims, characterised in that the wall thickness of the guarantee band (30) outside any radial thickening is between 0.5 and 0.8 mm.
8. Closure according to one of the preceding claims, characterised in that the guarantee band (30) is configured as a flex band with a radially outer part and a folded-over radially inner part.
9. Closure according to one of the preceding claims, characterised in that the minimum distance between the weakening lines (13, 14) is greater than 1.5 mm, preferably greater than 2 mm and in particular greater than 2.5 mm.
10. Closure according to one of the preceding claims, characterised in that the outer diameter of the closure lower part (40) above a pilferproof ring (35a), the inner diameter of the guarantee band (30), and the width and the circumferential extent of the upper separating web (11) are matched to one another in such a way that, after an opening rotation of the screw cap and the subsequent tilting of the screw cap (10) upon torsion of the holding bands (15, 16) together with the separating web (11), the free lower edge of the separating web engages with the lower part of the closure and is moved beyond a dead centre when a tilting angle of more than 90° is exceeded, so that the outside of the separating web (11) then comes into contact with the outside of the lower part of the closure and the screw cap (10) is stabilised in this position tilted by more than 90°.
11. Closure according to claim 10, characterised in that the outer diameter of the closure lower part (40) in a region above a pilferproof ring (35a) in which the guarantee band (30) of the closure is arranged is at most 2.5 mm, preferably at most 1.5 mm, smaller than the nominal inner diameter of the guarantee band (30).

Images