CA2250886A1

CA2250886A1 - Container cap and container mouth

Info

Publication number: CA2250886A1
Application number: CA002250886A
Authority: CA
Inventors: Udo Bosl; Lino Dreyer
Original assignee: Individual
Current assignee: Crown Cork AG
Priority date: 1996-05-09
Filing date: 1997-04-21
Publication date: 1997-11-20
Also published as: EP0904237A1; EP0904237B1; AU2501997A; ID18171A; ATE190029T1; DE59701183D1; AR006885A1; WO1997043188A1; MY132632A

Abstract

The invention concerns a snap-on cap or a screw cap which has a multiple thread and comprises auxiliary retention means (10) which can hold the cap in the axial direction on both sides of a container mouth (8) which is to be closed, before the cap retention elements (6) engage with the retention elements (7) on the container mouth (8) and close the latter sealingly in a leaktight position. The force (F1) required to press on the auxiliary retention means (10) is less than the closure force (F2). The auxiliary retention means (10) prevent the cap from popping off or tilting in a filling plant. Instead of the cap (1), the container mouth (8) can also be provided with auxiliary retention means (30), a conventional cap then being used.

Description

CA 022~0886 1998-10-01 Crown Cork AG, 4153 Reinach Container closure and container mouth The invention concerns a container closure, a container and a combination of a container closure and a container according to the preamble of the independent patent claims.

With industrial bottling plants, state-of-the-art closures for the closure of containers are placed upon containers intended for closure at high rates per hour. Placement se-quences are the same with regard to principle elements, regardless of whether snap or screw closures are concerned.
The closures are delivered by a so-called hopper and, by means of a transfer device, placed upon the mouths of con-tainers passing at high speed. In a subsequent process step, depending on type, the closures are either pressed or screwed onto the container mouth.

Because of the high speed of the passing containers, however, problems can occur prior to firm placement of the closures.
The closures can tilt while being put onto the closure mouth, or because of the high speed of the containers, they can jump off the container mouth before being pressed on or screwed on.

For example, plastic snap closures are proposed which possess flexible clips on their insides, said clips enabling the closure to be held upon a container mouth. Because of their flexibility, these clips permit only inadequate holding of the closure prior to actual placement onto the container mouth. In particular, in bottling plants, with such clips jumping off or tilting of the closure is still possible.

GB-A-2 063 226 discloses a snap-on closure having a non-circular cross section. The closure is held on a container CA 022~0886 1998-10-01 mouth by two ribs projecting inwardly from the inner surface.
The problem of the closure getting tilted or jumping off during application is not addressed in GB-A-2 063 226.

AU-A-519 377 discloses a closure which engages with two projections underneath two projections of a container mouth.
The two projections of the container engage at the same time with the projections of the closure cap. The problem of the closure getting tilted or jumping off during application is not addressed and solved here.

The purpose of the invention is to avoid the drawbacks of the state of the art, and in particular, therefore, to create a container closure and/or a container wherein jumping off or tilting of container closures in bottling plants is reliably prevented. The closures and containers according to the invention shall, in addition, be usable in state-of-the-art bottling plants without problems, and producible in an effi-cient and economic way.

According to the invention, these purposes are fulfilled with a container closure, a container mouth and a combination of a container closure and a container mouth according to the features of the characterizing portion of the independent patent claims.

A closure for a container possesses a closure base and a closure jacket. Retaining elements are provided on the inside of the closure jacket, said retaining elements being able to be brought into engagement with retaining elements on the container mouth on closure of the container by means of said closure. The retaining elements can be threads (preferably multi-start) or retaining beads of a snap closure.

In order that, in a bottling plant, the closure does not jump off the container mouth or tilt in relation to the container CA 022~0886 1998-10-01 mouth prior to definitive screwing or snapping on, in addi-tion the closure jacket possesses auxiliary retaining elements, said auxiliary retaining elements being able to be brought into engagement with the container mouth. Preferably the retaining elements in the mouth area of the container are employed as a holding means - it is, however, also conceiv-able to provide additional holding means adjacent to the retaining elements on the container mouth, or to press the closure onto the container mouth with the aid of the auxili-ary retaining elements while relying on straightforward friction.

The auxiliary retaining elements can, during placement of the closure onto the container, be brought into engagement with the container neck and/or its holding means, before the retaining elements of the closure come into engagement with the retaining elements of the container mouth. The auxiliary retaining elements and the retaining elements each possess a mechanical stop, said mechanical stop being able to be brought into contact with a surface of the retaining elements of the container mouth. As a result, the closure is restricted in both axial directions in an initial intermedi-ate position on the container mouth. At the same time, it is essential that the auxiliary retaining means are constructed in such a way that the force required for their placement is less than the force required during actual closing. If the closure is subsequently screwed on, a pressing force acting on a closure is required to place it by means of the auxili-ary retaining elements, and a torque is required for screwing on. With this construction, the closure is placed onto the container mouth without a large exertion of force, and is held on said container mouth before the actual closure sequence (snapping on or screwing on) occurs. A construction with such auxiliary retaining elements is mainly of advantage in the case of plastic closures with an elastic wall. The auxiliary retaining elements are snapped onto the mouth by CA 022~0886 1998-10-01 ' PCC040 means of elastic deformation of the cap wall and/or by means of their own inherent elastic deformation.

The mechanical stop of the auxiliary retaining means is arranged on its side oriented towards the cap base, while the mechanical stop of the retaining means is arranged on its side oriented away from the cap base. In the intermediate position, the container mouth retaining elements lie between both mechanical stops, by which means the closure position is restricted on both sides in the axial direction.

A particularly effective mechanical stop for the auxiliary retaining elements is attained if the auxiliary retaining elements are formed as an accumulation of material on the inside of the closure jacket. By means of an accumulation of material, a mechanical stop is formed which, in contrast to flexible clips, effectively resists jumping-off of the clo-sure in the intermediate position.

A particularly advantageous application of the retaining elements will result in combination with snap closures. Such snap closures possess a bead running around the inside of the closure jacket, approximately parallel to the closure base.
The bead serving as a retaining element is, on closure of the container, snapped over a correspondingly shaped bead on the mouth of the container. Thanks to the auxiliary retaining elements, the snap closure can, relying on a slight fric-tional connection, be placed upon the retaining bead of the container mouth prior to actual snapping-on. As a result, jumping off or tilting of the closure is reliably avoided.

Auxiliary retaining means are similarly advantageous in combination with multi-start threads as retaining elements.
The screw closure equipped with auxiliary retaining elements is, in an initial step, snapped onto the multi-start thread and as a result positioned exactly in relation to said CA 022~0886 1998-10-01 thread. Subsequently, the screw closure can be screwed on or, in the case of a snap-on and unscrewable closure, snapped on.

The mechanical stop of the multi-start thread is formed by the thread start on the side of the thread oriented away from the cap base.

When using snap closures with a retaining bead, said retain-ing bead preferably possesses interruptions. These interrup-tions increase the flexibility of the closure jacket and thus facilitate the placement sequence.

A particulary simple embodiment will result if, as auxiliary retaining elements, protrusions are used that project radially inwards from the inside of the closure jacket. These protrusions can be brought into engagement with the retaining elements on the container mouth, wherein said retaining elements fulfil the function of the previously described holding means. The protrusions must be dimensioned in such a way that the force required to overcome the auxiliary retain-ing means is less than the force for actual closure. This can, for example, occur through the auxiliary retaining elements defining a greater inside diameter than the retain-ing elements. A similar result is attained with protrusions that extend over a small angular area only. Apart from that, it is conceivable to form the protrusions sufficiently thinly so that they can snap flexibly over the retaining bead on the container mouth.

A particularly favourable embodiment will result if the retaining bead of a snap closure possesses interruptions, wherein an auxiliary retaining element in the form of a projecting protrusion is in each case is provided flush with one of these recesses. In order that the protrusions come into engagement with the retaining elements on the container mouth before the retaining bead, the protrusions must be ~. _ CA 022~0886 1998-10-01 arranged between the retaining bead and the free end of the closure jacket. Preferably, the auxiliary retaining elements are arranged adjacent to the free edge of the closure jacket.
As a result, a construction of the closure will result which is economic in terms of the amount of material used.

In order to reliably avoid tilting of the closure prior to the actual placement sequence, the auxiliary retaining elements are preferably arranged axisymmetrically around the circumference of the closure jacket, wherein at least two and preferably approximately four to six auxiliary retaining elements in the form of protrusions are used.

Similar advantageous embodiments result in combination with a screw closure.

From the manufacturing point of view, auxiliary retaining elements are simplest which are provided in the same way as the retaining elements on the inside of the closure jacket and which coordinate with the retaining elements of a con-tainer. It is also conceivable, however, to achieve the same result with other auxiliary retaining elements, said retain-ing elements being able to be brought into engagement with specially provided holding means on the container mouth.
Thus, for example, closures with an inner seal can be pro-vided with retaining elements on said inner seal, said elements being able to be brought into engagement with hold-ing means on the inside of the container mouth.

A similar behaviour during the placement sequence can also be attained if, in place of auxiliary retaining means on the closure, auxiliary retaining means are provided in the area of a container mouth. Here, similar embodiments to those described in the above will lead to particularly advantageous results. The auxiliary retaining elements can be formed as protrusions projecting from the outside surface of the con-CA 022~0886 1998-10-01 ~ PCC040 tainer mouth. The protrusions are arranged between the edge of the container mouth and the retaining elements of the container mouth (i.e. between a retaining bead or the upper side of a thread and the edge of the container mouth). In order that the force required to place the auxiliary retain-ing element is less than the closure force, respectively the closure torque, the auxiliary retaining elements (in the preferred embodiment the outwardly projecting protrusions) must be specially dimensioned. A simple design will result if the protrusions define an outside diameter on the container mouth that is less than the outside diameter as defined by the retaining elements of the container.

The mechanical stop of the auxiliary retaining elements of the container mouth is in this case arranged on the side of the protrusions oriented away from the container opening. The mechanical stop of the retaining elements of the container mouth is formed by the side of retaining elements oriented towards the container opening.

The magnitude of the frictional connection can, apart from that, also be be defined by the angular range over which the auxiliary retaining elements, i.e. the protrusions, extend.
The smaller the segments are kept, the less will be the press-on force required.

Because of the generally high material strength of the con-tainer mouth in comparison to the closure, the retaining bead is preferably formed circumferentially. The arrangement of recesses (as in the case of the closure) would, apart from bringing savings in material, be of little advantage. With a continuous circumferential retaining bead, the auxiliary retaining elements (protrusions) can for this reason be arranged in any desired way in relation to the container.
However, also in this case, an arrangement of at least two and preferably four to six protrusions is recommended, pre-CA 022~0886 1998-10-01 ferably arranged axisymmetrically to the axis of the con-tainer.

A basic consideration of the invention is therefore that, disregarding the retaining elements on a closure and a con-tainer mouth which permit fixing of the closure on said container mouth, auxiliary retaining elements are arranged on the closure and/or the container mouth, said auxiliary retaining elements being able to be brought into engagement with holding means on the container mouth and/or the closure.
With that, the auxiliary retaining elements must, at an intermediate position, come into engagement with the holding means before the retaining elements of the closure and of the container mouth come into mutual engagement. The retaining elements and the auxiliary retaining elements each possess a mechanical stop which, in this intermediate position, holds the closure fast on the container mouth in both axial direc-tions. In the intermediate position, both mechanical stops lie on both sides of the holding means and thus restrict the axial movement of the closure. The engagement of the auxili-ary retaining elements should, apart from that, with advan-tage be so designed that the force required for placement is less than the closure force, respectively the closure torque.

With a method for closing a container mouth with a closure, the closure is placed on the container mouth in a first step, and held on said container mouth in an intermediate position.
An initial press-on force is used to fix the closure in this intermediate position.

In the intermediate position, the position of the closure is restricted in both axial directions.

In a second step of the method, the closure is pressed into a second, sealing position with a second press-on force (or screw-on torque). The initial press-on force is selected to CA 022~0886 1998-10-01 be less than the second press-on force. As a result of the closure already being held firmly on the container mouth in the intermediate position, jumping off or tilting of the closure prior to applying the second press-on force is reliably prevented.

The invention is more closely explained in the following, with the aid of the drawings and in various embodiments:
namely, Figure 1 a closure according to the invention which is held with the auxiliary retaining elements in an intermediate position on a container (in cross section), Figure 2 a closure according to figure 1 which, in a sealing position, is placed firmly on a con-tainer, Figure 3 a view from below of a closure according to the invention, Figure 4 a cross section of a container mouth according to the invention with a closure placed upon said container mouth in the intermediate position, Figure 5 a plan view of a container mouth according to the invention, and Figure 6 a modified embodiment with a multi-start thread.

Figure 1 shows a closure 1 according to the invention, said closure placed in an intermediate position P1 on a container mouth 8 of a container 2. The closure possesses a closure base 3 and a closure jacket 4 extending downwards and attached to said base. Retaining elements 6 are provided on CA 022~0886 1998-10-01 the inside of the closure jacket 4, said retaining elements being able to be brought into engagement with retaining elements 7 on the outside of the container mouth 8. The retaining elements 6 on the inside 5 of the closure jacket 4 are formed by a circumferential bead running approximately parallel to the closure cap 3. The bead is interrupted by individual interruptions 17 that increase the flexibility of the cap wall 4. The retaining elements 7 of the container mouth 8 are likewise formed by a circumferential bead on the outside of the container mouth 8.

The closure 1 possesses auxiliary retaining elements 10 on the inside which likewise can be brought into engagement with the retaining elements 7 on the container mouth 8. The aux-iliary retaining means 10 are formed as protrusions project-ing radially inwards on the inside 5 of the closure jacket 4.
The auxiliary retaining elements possess a mechanical stop 13 arranged on their side oriented towards the cap base 3. The retaining elements 6 possess a mechanical stop 14 on their side oriented away from the cap base 3. The retaining elements 7 of the container mouth 8 lie in the intermediate position Pl between both the contact surfaces 13, 14 of the auxiliary retaining elements 10 and the retaining elements 6.
The protrusions are formed to be solid, so that the mechan-ical stop 13 enables reliable axial holding of the closure on the container mouth. In figure 1, the closure 1 is held by the auxiliary retaining elements 10 in the intermediate position Pl on the container mouth 8. The auxiliary retaining elements 10, in other words the inwardly projecting protru-sions, are arranged adjacent to the lower edge of the closure 1 so that, on placement of the closure 1 onto a container mouth, they come into engagement with the retaining elements 7 of the container mouth 8 before the retaining elements 6.
The auxiliary retaining elements 10 define a free inside diameter that is greater than the free inside diameter as defined by the retaining elements 6. The force required to CA 022~0886 1998-10-01 place the auxiliary retaining elements 10 is therefore less than the actual closure force.

Figure 2 shows the closure from figure 1 which is completely placed upon a container mouth 8 in a sealing position P2.
Because the retaining elements 6 of the closure 1 define a smaller free inside diameter than the auxiliary retaining elements 10, the closure 1 in the position shown in figure 2 is held more firmly on the container mouth 8 than the posi-tion shown in figure 1. The position in figure 1 serves only to temporarily hold the closure on the container mouth 8 so that jumping off or tilting is avoided. In the position shown in figure 1, however, the container is not closed to form a seal.

The mechanical stop 13 of the auxiliary retaining elements 10 is no longer required in the sealing position P2. It is naturally conceivable, with the closure, to briefly reclose containers that have already been opened by using only a small press-on force in order to once again bring the closure into the intermediate position. In this case, a sealing reclosure is not possible, but the container mouth can be protected from contamination or the intrusion of insects.

Figure 3 shows a view from beneath of the closure shown in figures 1 and 2. Retaining elements 6 are provided in the form of a circumferential bead on the inside 5 of the closure jacket 4. The bead is interrupted by five interruptions 17, by which means the flexibility and elasticity of the closure jacket 4 is increased. An auxiliary retaining element 10 in the form of an inwardly projecting protrusion is provided in each of the interruptions 17. The auxiliary retaining elements 10 are dimensioned in such a way that the free inside diameter that they define is greater than the free inside diameter defined by the retaining elements 6. The five auxiliary retaining elements 10 are (in the same way as the CA 022~0886 l998-lO-Ol interruptions 17) distributed around the closure jacket 4 axisymmetrically to the axis of the closure.

Figure 4 shows a further embodiment with the features of the invention. A container mouth that can be closed with a con-ventional snap closure possesses auxiliary retaining elements 30 on its upper edge 21. On placement of a conventional snap closure, without great exertion of force, the closure can be brought with its retaining elements 6 into engagement with the auxiliary retaining elements 30 of the container mouth 8.
The auxiliary retaining elements 30 are formed as radially outwardly projecting protrusions, the outside diameter of which is less than the outside diameter as defined by the retaining elements 7 of the container mouth 8. The auxiliary retaining elements 30 possess a mechanical stop 34 arranged on their side oriented away from the container opening. A
circumferential bead is used as retaining elements 7, said bead possessing a mechanical stop 33 on its side oriented toward the container opening. The auxiliary retaining elements 30 are provided between the retaining elements 7 and the upper edge 21 of the container mouth 8.

Similar to a closure according to the invention, with a container mouth 8 according to the invention an axi-symmetrical arangement of the auxiliary retaining elements 30 is also advantageous. Figure 5 shows a container mouth 8 in plan view, wherein four auxiliary retaining elements 30 in the form of outwardly projecting protrusions are arranged axisymmetrically. The auxiliary retaining elements 30 define a smaller outside diameter than the retaining elements 7.

Figure 6 shows a further embodiment of a closure according to the invention on a container mouth 8. In place of a snap closure, a closure with a multi-start thread is shown here.
The closure 1 possesses an auxiliary retaining element 10 on its lower edge, said auxiliary retaining element coming into CA 022~0886 1998-10-01 engagement with the threads 36 of the container mouth 8 before the threads 16 of the closure come into engagement with the threads 36 of the container mouth 8. On placement of the closure 1 onto the container mouth, the auxiliary retain-ing elements 10 first come into engagement with the uppermost section of the threads 36 and are held with a comparatively slight frictional connection on the container mouth 8.
Subsequently, the closure 1 can be screwed on firmly with conventional screw-on heads, or pressed on in the case of a closure capable of snapping on and unscrewing.

Naturally, in the case of closures with threads, an embodi-ment is conceivable which possesses auxiliary retaining elements on the container mouth 8.

Inasmuch as the invention is subject to modifications and variations, the foregoing description and accompanying draw-ings should not be regarded as limiting the invention, which is defined by the following claims and various combinations thereof:

Claims

claims

1. Closure (1) for a container (2), with a closure base (3) and a closure jacket (4) possessing on its inside (5) at least one retaining element (6), said retaining element, in order to close the container (2) by means of the closure (1), being able to be brought into engagement and closed with at least one retaining element (7), wherein the closure (1) possesses at least one auxiliary retaining element (10) which, on placement of the closure (1) onto the container (2), is able to be brought into engagement with the container mouth (8), in particular with the retaining element (7) on the container mouth (8), before the retaining element (6) of the closure (1) comes into engagement with the retaining element (7) of the container (2), characterized in that the auxiliary retaining elements (10) and the retaining elements (7) each possess a mechanical stop (13, 14), said mechanical stop being able to be brought into engagement with the retaining elements (7) of the container mouth (8) in such a way that the position of the closure (1) is restricted on the container mouth (8) in both axial directions.

2. Closure according to claim 1, characterized in that the retaining element (6) of the closure (1) comprises a bead projecting radially inwardly from the inside surface (5) of the closure jacket (4) and running approximately parallel to the closure base (3), wherein the mechanical stop (14) is arranged on the side of the bead oriented away from the cap base (3).

3. Closure according to claim 1, characterized in that a multi-start thread on the inside (5) of the closure jacket (4) is provided as a retaining element (6), wherein the mechanical stop is formed by the thread start oriented away from the cap base.

4. Closure according to claim 2, characterized in that the circumferential bead possesses interruptions (17).

5. Closure according to one of the claims 1 to 4, characterized in that the auxiliary retaining elements (10) are formed by protrusions projecting radially inwards from the inside surface (5) of the closure jacket (4), wherein the mechanical stop (13) of the auxiliary retaining elements (10) is arranged on the side of the protrusions oriented towards the cap base (3).

6. Closure according to claim 4, characterized in that in each case one auxiliary retaining element (10) is arranged in one of the interruptions (17).

7. Closure according to one of the claims 1 to 6, characterized in that the auxiliary retaining elements (10) are arranged axisymmetrically in relation to the axis of the container-closure.

8. Container mouth (8) with an opening (20) and an edge (21) surrounding said opening (20), and a circumferential outside surface (22) extending downwards from said edge (21), said surface possessing at least one retaining element (7) which can be brought into engagement with at least one retaining element (6) of a closure (1) in order to close the container mouth (8), wherein the container mouth (8) possesses at least one auxiliary retaining element (30) which, on placement of the closure, is able to be brought into engagement with holding means, preferably with the retaining element (6), of the closure (1) before the retaining element (7) of the container mouth (8) comes into engagement with the retaining element (6) of the closure (1), characterized in that the auxiliary retaining elements (30) and the retaining element (7) each possess a mechanical stop (34, 33) said mechanical stop being able to be brought into engagement with the retaining elements (6) of the closure in such a way that the position of the closure (1) on the container mouth (8) is restricted in both axial directions.

9. Container mouth (8) according to claim 8, characterized in that the retaining elements (7) comprise a circumferential bead projecting radially outwards from the outside surface (22) and running approximately parallel to the edge (21), wherein the mechanical stop (33) of the retaining elements (7) is arranged on the side of the retaining elements (7) oriented towards the container mouth.

10. Container mouth (8) according to claim 8, characterized in that the retaining elements (7) comprise preferably a multi-start thread on the outside surface (22) of the container mouth (8), wherein the mechanical stop (33) is formed by the side of the retaining elements oriented towards the container mouth.

11. Container mouth (8) according to one of the claims 8 to 10, characterized in that the auxiliary retaining elements (30) are formed by protrusions projecting radially outwards from the outside surface (22), wherein the mechanical stop (34) of the auxiliary retaining elements (30) is arranged on the side of the auxiliary retaining elements (30) oriented away from the container opening.

12. Container mouth according to one of the claims 8 to 11, characterized in that the, at least two and preferably four to six, auxiliary retaining elements (30) are arranged axisymmetrically to the axis of the container mouth (8).

13. Combination of a closure (1) and a container mouth (8), said container mouth (8) being able to be closed by means of the closure (1), wherein the closure possesses a closure base (3), a closure jacket (4) and retaining elements on the inside (5), and wherein the container mouth (8) possesses an opening (20), an edge (21) surrounding said opening (20) and an outside surface (22) extending downwards from said edge (21), said outside surface being provided with at least one retaining element (7), wherein the retaining element (6) of the closure is able to be brought into engagement with the retaining element (7) of the container mouth (8) in order to close the container mouth (8), and wherein the closure (1) and/or the container mouth (8) possess auxiliary retaining elements (10, 30) which, on placement of the closure, can be brought into engagement with holding means (11, 31) of the container mouth (8) and/or the closure (1) before the retaining elements (7) of the container come into engagement with the retaining elements (6) of the closure, characterized in that the auxiliary retaining elements (10, 30) and one of the retaining elements (6, 7) possess a mechanical stop (13, 14;
33, 34), said mechanical stop being able to be brought into contact with the respective mechanical stops of the retaining elements (7, 6) in such a way that the position of the closure (1) on the container mouth (8) is restricted in both axial directions.

14. Combination according to claim 13, characterized in that the container mouth (8) is equipped with auxiliary retaining elements (30).

15. Combination according to claim 13, characterized in that the closure (1) is equipped with auxiliary retaining elements (10).

16. Combination acording to claim 14, characterized in that the holding means are formed by retaining elements (6) of the closure (1).

17. Combination according to claim 15, characterized in that the holding means are formed by the retaining elements (7) of the container mouth (8).

18. Closure according to one of the claims 1 to 7, characterized in that the auxiliary retaining element (10) is arranged in such a way that the press-on force required for its placement is less than the force required to close the closure.

19. Container mouth according to one of the claims 8 to 12, characterized in that the auxiliary retaining element (30) is arranged in such a way that the press-on force required for its placement is less than the force requires to close the closure.

20. Combination according to one of the claims 13 to 17, characterized in that the auxiliary retaining elements (10, 30) are arranged in such a way that the press-on force required for their placement is less than the force required to close the closure.

21. Method for closure of a container mouth (8) with a closure (1), characterized by the following steps:

- placement of the closure (1) onto the container mouth (8) in an intermediate position (P1) by means of an initial press-on force wherein, in the intermediate position (P1), the closure is restricted in the axial direction on both sides, - pressing-on of the closure in a sealing position (P2) by means of a second press-on force (F2), wherein the second press-on force (F2) is greater than the initial press-on force (F1).