EP0951428B1 - Plastics screw-type cap for bottles, provided with a tamperproof strip - Google Patents

Abstract

A screw-type bottle cap having a body with an internal thread and a tamperproof strip which has at least one expansion structure that includes at least one point at which it is fixed to the cap body. In this way, a screw-type cap is produced which has a reliable tamperproof function wherein the tamperproof strip remains attached to the cap body when the cap is unscrewed, without the free ends of the strip protruding from the cap body.

Description

The present invention relates to a screw cap made of plastic for Bottles, with a closure body having an internal thread and a Guarantee band. This has holding cams lying on the inside non-tearing and bridges with the closure body connected. In the bridges when unscrewing the closure body from the bottle the train so high that they tear. The guarantee band has one Stretching device, being between the guarantee band and the Closure body in the region of the stretching device at least one fixed point is provided.

Such screw caps are widespread and are used in particular Glass or plastic bottles used for soft drinks. These bottles are standardized in different sizes and are very large Number of pieces in circulation, be it as one-way or as reusable bottles. In particular, the bottle neck is threaded in these bottles standardized so that despite different sizes uniform Screw caps can be used. This offers many Advantages, however, has the crucial disadvantage that because of the constantly changing a change in the number of bottles in circulation Bottle neck geometry is hardly possible, and thus the screw caps as so-called disposable items to the given bottle neck or Thread geometry must be adjusted. Changes in the system Bottle neck screw cap can therefore only economically on Screw closure can be made.

The known plastic screw caps for bottles have usually a closure body with an internal thread and a Guarantee tape on. The guarantee band is usually designed so that it at least when opening the screw closure from the closure body partially solves. This is to show the consumer whether the bottle has already been opened or is still intact. The guarantee band is usually formed as a ring and by thin bridges with the Lock body connected. Furthermore, the guarantee band on the Holding cams or slats on the inside, which are screwed on Form a so-called locking ring and the locking ring of the bottle engage behind. This is usually connected to the external thread Bottle body arranged on the bottle neck and points in the standardized shape a slightly larger or the same diameter than the external thread arranged in front of it. Since he is towards the bottle body is slightly tapered, the guarantee band expands when Unscrew the screw cap due to the given basic elasticity of the plastic in the circumferential direction from something, so that the arranged inside Holding cams or slats of the guarantee band over the locking ring can slide away and snap into place after the screwing process is finished and reach behind the locking ring.

When the bottle is screwed on, the retaining cams or lamellae now hold this Guarantee tape firmly on the locking ring, while those intended as a predetermined breaking point Break bridges due to the tensile force that occurs in the material. Because of that destroyed connection between the guarantee band and the closure body is on one You can see that the bottle has already been opened.

There are now essentially two embodiments of the guarantee bands known. In the first known embodiment of the guarantee tape triggers this completely when screwing on the screw cap Closure body and remains as a ring on the bottle neck. However, this is particularly disadvantageous with regard to disposal, since by the Bottleneck guarantee band for disposable bottles that after single use can be melted down again, the melt is contaminated. In the case of reusable bottles, however, must be re-used Fill and close the old one with a screw cap Guarantee tape must be removed before the new screw cap is applied can be.

But environmental aspects also speak against this embodiment, since that first of all the guarantee band remaining on the bottle neck, for example at Transport of the empty bottle can detach itself from the bottle neck then loses as unwanted garbage in the environment.

But also aesthetic aspects that are becoming increasingly important Are selling points, speak against the remaining at the bottle neck Guarantee tape, as this is perceived by many consumers as annoying.

The second known embodiment of the guarantee tape breaks at Unscrew the screw cap, but remains completely on Closure body. Here in particular the protruding ends of the Guaranteed tape considered disadvantageous, since it when screwing on or unscrewing of the screw cap disturb the consumer and also cause injuries being able to lead. But the aesthetics also speak against this embodiment of the guarantee tape, since the protruding ends are disruptive by the consumer be felt.

US-A-5,246,125 is specified as the closest prior art. The screw cap presented in it has the aforementioned Characteristics. When screwing this screw cap on and off Bottle is the guarantee band due to the existing stretching device in stretched in the axial direction and over the fixed point in the area of Expansion device held on the closure body. This behavior is, of course very problematic in the demolding in the manufacturing process, because the Bridges between the guarantee band and the closure body during demolding be stressed on train and therefore tend to Tear manufacturing process.

Another plastic screw cap is known from the DE-A-42 06 123, in which also a guarantee band with the bridges Closure body is connected. The guarantee band also points to this Screw cap on an expansion device, but which is also only in extends in the axial direction.

Against this background, it is an object of the present invention a plastic screw cap for bottles, with a Closure body, having an internal thread, and a guarantee tape for To provide, which has a secure guarantee function and without protruding ends on the closure body remains.

This problem is solved in that the stretching device the guarantee tape when screwing the closure body onto the bottle over its entire Height evenly extends in the radial direction so that the retaining cams over the Slide the locking ring away.

This inventive design of a screw cap both achieved a safe guarantee function and the remaining of the Guaranteed tape on the closure body guaranteed. When screwing on the Screw cap on the bottle neck stretches the guarantee band the conical design of the locking ring and therefore slides with its Holding cams or slats over the locking ring while the bridges between the guarantee band and the closure body when screwed on under pressure be burdened and therefore do not tear.

When opening the bottle, however, by unscrewing the screw cap the retaining cams or slats first hold the guarantee band on the locking ring firmly, so that the bridges between the guarantee band and the closure body now be loaded on train. By turning the closure body further, the Train in the bridges further increased so that they finally tear. The However, the guarantee tape remains on the closure body due to the fixed point, while by further turning the closure body the tension in Guarantee band is further increased and thereby the stretching device Guarantee tape stretches so far that it can slide over the locking ring. The Screw cap can now be completely unscrewed, the Guarantee band still connected to the closure body by the fixed point and the torn bridges between the guarantee band and the closure body indicate that this screw cap has been operated. The consumer therefore immediately recognizes that this bottle has already been opened. Furthermore, the guarantee tape remains on the closure body, so that none Disposal or environmental problems arise. Eventually, that breaks Guarantee tape when unscrewing also not, so that none the consumer protruding or hurtful guarantors protrude and therefore a altogether also aesthetically acting screw closure provided becomes.

According to a preferred embodiment, the stretching device at least two recesses which are essentially transverse in Guarantee band run and to each opposite Guarantee band edges are open. This is particularly easy an expansion of the guarantee band by this accordion-like is drawn out. The guarantee band advantageously has two on opposite guarantee tape sides arranged expansion devices. This makes it easy to evenly stretch the guarantee band enables so that this easily and without getting stuck at Unscrewing the screw cap can slide over the locking ring.

An advantageous development of the invention provides that the Stretching device has two recesses on one side of the Fixed point are arranged. This will allow a targeted stretching of the Guaranteed tape possible from one side of the fixed point.

According to another preferred embodiment, the stretching device two recesses on opposite sides of the fixed point are arranged so that here the stretching of the guarantee band from the fixed point from both sides.

According to a particularly preferred development of the invention provided that the guarantee tape is free of vertical tear lines. With in other words, there is no vertical predetermined breaking point in the guarantee band provided, as is the case, for example, with screw closures according to DE-A-42 06 123 and EP-A-0 460 557 is the case. In this embodiment the guarantee band is separated into two functional halves. The first half serves essentially, the stretching of the guarantee band during manufacture and to apply to the bottle when screwing on. The Stretching function is essentially due to the undercut of the Holding cams and a further connection to the closure body ensured.

This first half of the guarantee band can be free and independent of the Extremely stretch the second half. The second half of the guarantee band serves essentially to ensure the guarantee function. By the Expansion element in connection with a horizontal integration is the Elongation ensured during manufacture. The sense of separation in two functional halves in this embodiment can be seen in that the second half has to take up less expansion than the first half. This will ensure the guarantee function and that Reclosure of the bottles improved again by the consumer.

Fig. 1

eine Seitenansicht einer ersten Ausführungsform des erfindungsgemäßen Schraubverschlusses im aufgeschraubten Zustand mit einem Teilschnitt durch das Garantieband,

Fig. 2

eine Seitenansicht der ersten Ausführungsform beim Aufschrauben mit zwei Teilschnitten durch das Garantieband,

Fig. 3

eine Seitenansicht der ersten Ausführungsform beim Abschrauben mit einem Teilschnitt durch das Garantieband,

Fig. 4

eine perspektivische Ansicht des Garantiebandes der ersten Ausführungsform,

Fig. 5

eine Seitenansicht einer zweiten Ausführungsform des erfindungsgemäßen Schraubverschlusses im aufgeschraubten Zustand mit einem Teilschnitt durch das Garantieband,

Fig. 6

eine Seitenansicht der zweiten Ausführungsform beim Aufschrauben mit zwei Teilschnitten durch das Garantieband, und

Fig. 7

eine Seitenansicht der zweiten Ausführungsform beim Abschrauben mit zwei Teilschnitten durch das Garantieband.

The invention is explained in more detail below on the basis of exemplary embodiments. It shows:

Fig. 1

2 shows a side view of a first embodiment of the screw closure according to the invention in the screwed-on state with a partial section through the guarantee band,

Fig. 2

2 shows a side view of the first embodiment when screwing on with two partial cuts through the guarantee band,

Fig. 3

2 shows a side view of the first embodiment when unscrewing with a partial section through the guarantee band,

Fig. 4

2 shows a perspective view of the guarantee band of the first embodiment,

Fig. 5

2 shows a side view of a second embodiment of the screw closure according to the invention in the screwed-on state with a partial section through the guarantee band,

Fig. 6

a side view of the second embodiment when screwing with two partial sections through the guarantee tape, and

Fig. 7

a side view of the second embodiment when unscrewing with two partial sections through the guarantee tape.

In Fig. 1 is a side view of a first embodiment of the Screw cap 10 according to the invention shown. The screw cap 10 consists essentially of the closure body 12 and the guarantee tape 14 and is screwed onto a bottle neck 30. The guarantee tape 14 is with the bridges 16 and the fixed point 18 with the closure body 12 connected. Furthermore, the guarantee band 14 has holding cams 15 on the inside and a stretching device 20. This stretching device 20 has two Recesses 22 and 24, which are each formed as a slot. there the recess 22 is open to the closure body 12, while the Recess 24 is open to the bottle body, of which the simplicity only the bottle neck 30 is shown.

In the screwed-on state shown here, the guarantee band is 14 not stretched and the holding cams 15 engage behind the locking ring 32 on the Bottle neck 30.

In Fig. 2, the first embodiment of the screw cap 10 is Screwed onto the bottle neck 30 shown just before the holding cams 15 engage behind the locking ring 32. Due to the conical formation of the Locking ring 32 are the retaining cams 15 of the guarantee band 14 and thus that Guarantee tape 14 even when screwing the screw cap 10 onto the Bottle neck 30 pressed radially outwards. Through the stretching device 20 with the two recesses 22 and 24 is an accordion-like Extension of the guarantee band 14 enables, as shown in Fig. 2. There the closure body 12 of the screw cap 10 when screwing on presses the fixed point 18 and the bridges 16, these are loaded under pressure and therefore cannot tear. If the screw cap is now on the Bottle neck 30 screwed on, reach behind the holding cams 15 of the Guarantee band 14, the locking ring 32 and the guarantee band 14 pulls again together. The state shown in FIG. 1 is then achieved.

In Fig. 3, the first embodiment of the screw cap 10 is now Unscrew from the bottle neck 30 shown. The first on the locking ring 32nd adjacent retaining cams 15 hold the guarantee band 14 and thus over the Fixed point 18 and the bridges 16 also the closure body 12 on the Bottle neck 30 tight. By further turning the closure body 12 Train in the bridges 16 finally so strong that they tear. The Guarantee band 14 is however on by the fixed point 18 on Closure body 12 held so that by the stretching device 20 with the Recesses 22 and 24, the guarantee band 14 is stretched and the Hold cam 15 slide over the locking ring 32. The screw cap 10 can then be completely unscrewed from the bottle neck 30 while the guarantee band 14 is still on the closure body 12 and none protruding ends. Due to the torn off bridges 16 immediately recognizable that this closure has already been used.

The stretching device 20 with the recesses 22 and 24 allow that the guarantee band 14 is stretched (widened) so that a problem-free Resealing the bottle neck 30 is possible.

4, the guarantee band 14 of the first embodiment is in one shown perspective view. The guarantee band 14 has two on opposite sides arranged stretchers 20, each have two recesses 22 and 24 respectively. These recesses 22 and 24, respectively are designed as slots, each facing the opposite Guarantee band edges are open. On the inside of the guarantee band 14 are holding cams 15 which are shown in the here Embodiment are arranged section by section. However, you can too be arranged all around on the inside. On the top of Guarantee band 14 are finally two fixed points 18 and several Bridges 16 formed.

In the first embodiment according to Figures 1 to 4 is on vertical Tear lines have been dispensed with, which makes it possible to use the closure thick guarantee band and strong undercut of the holding cams 15 without additional cutting process. Through the expansion element 20 an extreme stretch of the guarantee band 14 in the final shaping during Manufacturing process and when screwing onto the bottle neck ensured. The natural resilience of Made use of plastics. The extension of the guarantee band 14 must by choosing the wall thicknesses within the expansion element 20 and the Cross section of the bridges 16 are adjusted so that the guarantee band 14th does not tear off during manufacture and the natural resilience of the plastic used is preserved as much as possible.

This is essentially due to the choice of the wall thicknesses of the two horizontal connections x and y (Figure 3) of the expansion element reached. If it is not only necessary to break the bridges 16, then by an extreme stretch of the guarantee band 14 and by appropriate Wall thickness difference between the connections x and y also the Connection x to be brought to tear. The connection y would be in this Trap thicker than the connection x.

5 is a second embodiment of the invention Screw cap 10 shown. The screw cap 10 consists in essentially of a closure body 12 and a guarantee tape 14 and is shown here screwed onto a bottle neck 30. The Guarantee band 14 is with a fixed point 18 and bridges 16 at Closure body 12 attached. The guarantee band 14 has on the inside Holding cams 15, the in the screwed state shown here Reach behind locking ring 32. Furthermore, the guarantee band 14 has a Expansion device 20, also with two recesses 22 and 24. Die Recesses 22 and 24 are designed as slots and are each closed opposite edges of the guarantee band. In contrast to the first Embodiment shown in Figs. 1 to 4 is shown in this second Embodiment of the fixed point 18 between the two recesses 22nd and 24 arranged.

6, the second embodiment is in a side view with a Partial section through the guarantee tape 14 shown when screwing, and in Fig. 7 when unscrewing. Since the operation of the stretching device 20th already in detail with reference to FIGS. 1 to 4 has been described, there is no need for a new description here.

Vertical tear lines are also dispensed with in this embodiment. Here the guarantee band 14 is separated into two functional halves A and B.

The first half A essentially serves to expand the Guarantee tape 14 in the manufacture when screwing on the Take over bottle. The stretching function is essentially determined by the Undercut of the holding cams 15, the bridges 16 and the connection N (Figure 6) ensured. Half A can be free and independent of the Extremely stretch the second half B. Optionally, it can still be useful an additional light connection Z (shown in dashed lines in FIG. 6) provided.

The second half B essentially serves to ensure the Guarantee function. By the expansion element 20 in conjunction with the horizontal connection M (Figure 6), the stretch during the Manufacturing ensured. Because of the difference in wall thickness essentially the same is achieved between the connections M and Z. as in the first embodiment by the differences in the Connections X and Y.

The purpose of the separation into two functional halves A and B is to be seen in that the second half B has to take up less expansion than the first half A. This will ensure the guarantee function and that Reclosure of the bottles improved again by the consumer.

LIST OF REFERENCE NUMBERS

10

screw

12

closure body

14

guarantee strip

15

holding cams

16

bridges

18

benchmark

20

stretching device

22

recess

24

recess

30

bottleneck

32

locking ring

Claims (6)

1. Screw closure (10) made from plastic for bottles which have on their bottle neck a locking ring (32), having a closure body (12) which has an inner thread, and having a tamperproof strip (14) having retaining cams (15) lying on the inner side which is designed to be non-tearing, is connected to the closure body (12) via bridges (16), in which during unscrewing of the closure body (12) from the bottle, the tension is increased so that they tear, and which has an extension device (20), wherein at least one solid point (18) is provided between the tamperproof strip (14) and the closure body (12) in the region of the extension device (20), characterised in that the extension device (20) extends the tamperproof strip (14) during screwing of the closure body (12) onto the bottle over its entire height uniformly in radial direction so that the retaining cams slide over the locking ring (32).
2. Screw closure according to claim 1, characterised in that the extension device (20) has at least two recesses (22, 24), which run essentially transversely in the tamperproof strip (14) and are open to in each case opposing tamperproof strip edges.
3. Screw closure according to claim 2, characterised in that the tamperproof strip (14) has two extension devices (20) arranged on opposing tamperproof strip sides.
4. Screw closure according to claim 3, characterised in that the extension device (20) has two recesses (22, 24), which are arranged on one side of the solid point (18).
5. Screw closure according to claim 3, characterised in that the extension device (20) has two recesses (22, 24), which are arranged on opposing sides of the solid point (18).
6. Screw closure according to one of claims 1 to 5, characterised in that the tamperproof strip (14) is free of vertical tear lines.

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