US20080035599A1

US20080035599A1 - Stopper for Closing a Bottle

Info

Publication number: US20080035599A1
Application number: US11/572,256
Authority: US
Inventors: Ernst Seibel
Original assignee: Seibel Plastiko AG
Current assignee: Seibel Plastiko AG
Priority date: 2004-07-17
Filing date: 2005-07-15
Publication date: 2008-02-14
Also published as: DE102004034709B3; WO2006008095A1; EP1768915A1

Abstract

A stopper for closing a bottle, with a sealing body and with a handle cap, onto which a connecting mandrel penetrating into the sealing body is integrally formed, the sealing body being relatively resilient as compared with the handle cap, shall enable, with relatively simple manufacture and relatively great freedom of choice of the material, a reliable sealing, avoiding an impairment of the contents, even after frequent re-closing of a bottle. For this purpose, according to the invention, the handle cap includes an enclosure for the sealing body, whose free cross-section is smaller than the cross-section of the sealing body, the handle cap being firmly connected with the sealing body through a frictional connection between the connecting mandrel and the sealing body surrounding it, as well as by a frictional connection between the enclosure and the sealing body.

Description

The present invention relates to a stopper for closing a bottle, with a sealing body and with a handle cap, onto which a connecting mandrel penetrating into the sealing body is integrally formed, the sealing body being relatively resilient as compared with the handle cap.

BACKGROUND

Many wine and spirit bottles, but also containers for other foodstuff, such as vinegar or syrup, or for cosmetic or medical products, are closed with a sealing stopper inserted into the pouring opening of the neck of the bottle. Usually, such a stopper includes a sealing body, which can be made of natural cork, but also of a synthetic material, in particular a foamed synthetic material, and which is, as a rule, characterized by its resilient behavior, in relation to the bottle body, which decisively contributes to the sealing effect.
In many cases, it is desirable to make it possible to open a bottle closed in this way by hand without using any aids, such as a corkscrew, and to close it afterwards again with the undamaged sealing body. Especially for a spirit bottle, from which usually only small quantities are taken at a time, the procedure might be repeated several times, until the contents of the bottle are exhausted. For this purpose, the associated sealing stopper can be manufactured in the so-called “bartop” version, in which the upper end of the sealing body, facing the pouring opening, is connected with a handle body or a handle cap. To give the consumer an impression of high quality and to achieve a repeated usability as well as a long durability, the handle cap in such an execution is usually made of a material which is hard and resistant to pressure as compared with the sealing body. To join the two components with each other, a connecting mandrel penetrating into the sealing body can be integrally formed onto the handle cap of such stoppers.
For the above-mentioned purpose, a durable and stable connection of handle cap and sealing body is desired. To guarantee this, glues may be used, as known, for example, from FR 1 021 819 A, which fix the connecting mandrel in the sealing body. To realize a good surface attachment and a sufficiently good durability, the connecting mandrel of such a stopper joined by material engagement has, as a rule, a relatively large surface, with a corresponding design of the sealing body. It is a disadvantage of this joining method using material engagement that usually a mechanical and/or chemical preparatory treatment of the adherends is necessary to achieve sufficient strength of the glued joint. Especially when using stoppers made of synthetic material, which are usually manufactured on the basis of ethylenes, but also stoppers made of natural cork, the achievable strength is, furthermore, limited. It is also relatively frequent that cracks occur in the immediate vicinity of the glued joint, which might lead to the stopper breaking into pieces. Furthermore, there is the risk that traces of the glue diffuse through the possibly porous material of the sealing body into the interior of the sealed bottle, which may affect the taste of the contents or even be detrimental to health.
An alternative method, also using material engagement, for producing a durable connection between handle cap and sealing body is based, in the case of a stopper made of a pure synthetic material, on the application of the so-called two-component ejection-molding method, in which two different, but compatible, melting charges of synthetic materials are injected approximately simultaneously into a mold. During the curing process, two layers connected with each other through molecular forces develop, the outer layer forming the sealing body and the inner layer, the connecting element of the handle cap. However, due to the compatibility requirements, this method considerably restricts the choice of suitable materials. Furthermore, it requires, just as the first method described, relatively complicated and expensive manufacturing steps.
From JP 2001 048 204 A, for example, a stopper is known whose handle cap is fixed in the sealing body by means of a screw-shaped connecting mandrel. However, both the manufacture of such a connecting mandrel and the screwing together of handle cap and sealing body are relatively expensive. Furthermore, a combined rotating and pulling movement to remove such a stopper from a bottle may relatively easily screw the handle cap out of the sealing body, the sealing body possibly remaining in the neck of the bottle. This is, however, most undesired.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a stopper of the above-mentioned type, which enables, with relatively simple manufacture and relatively great freedom of choice of the material, a reliable sealing, avoiding an impairment of the contents, even after frequent re-closing of a bottle.
The present invention provides a stopper for closing a bottle, with a sealing body and with a handle cap, onto which a connecting mandrel penetrating into the sealing body is integrally formed, the sealing body being relatively resilient as compared with the handle cap, characterized in that the handle cap includes an enclosure for the sealing body, whose free cross-section is smaller than the cross-section of the sealing body, the handle cap being firmly connected with the sealing body through a frictional connection between the connecting mandrel and the sealing body surrounding it, as well as by a frictional connection between the enclosure and the sealing body.
Advantageous embodiments of the invention are the subject matter of the claims.
An impairment of the contents of the bottle through impurity diffusion might be due to the use of glues or adhesion promoters for fixing the handle cap and the sealing body of the closing stopper. To avoid this, the two components should, therefore, be connected without using such glues or adhesion promoters. The use of glue in the manufacture of the composed stopper, which might possibly be problematic from the point of view of food chemistry as well as undesired in view of the work required, can be avoided by realizing the retention forces necessary for sufficient strength of the connection between handle cap and sealing body in an alternative manner. For this, a purely mechanical way of force generation is provided, producing a frictional connection between the components, making use of the fact that the sealing body consists of a relatively soft material, which has resilient properties as compared with the relatively hard material of the handle cap. A possible insertion of the connecting mandrel integrally formed onto the handle cap into the resilient sealing body with sufficiently high force, either producing a holding channel in the sealing body, which encloses the connecting mandrel, or expanding an already existing (pilot-drilled) holding channel, will, therefore, lead to a surface pressure due to a resilient deformation of the sealing body. Therefore, due to the acting frictional forces, there exists a frictional connection between the connected components.
An even greater mechanical stability of the joined stopper is achieved by the handle cap including an enclosure for the sealing body, whose free cross-section is smaller than the cross-section of the sealing body. Therefore, in this place, too, a frictional connection prevents an undesired detachment of the handle cap from the sealing body. In other words: As the free cross-section of the enclosure is slightly smaller than the originally provided cross-section of the resilient sealing body at its edge portion facing the handle cap, the sealing body can only be pressed into the enclosure of the handle cap with increased expenditure of force and under resilient deformation of the material of the sealing body. That means that due to the resilient surface pressure, in this place, too, an effective clamping joint is realized between the handle cap and the sealing body. It turned out in many tests and in daily use that it is exactly this clamping joint on the enclosure that contributes to a particularly high stability of the sealing stopper against mechanical stress—for example, due to the forces and torques acting on the handle cap when pulling the stopper out of the neck of the bottle. The pressing action of the enclosure does not only increase the admissible tensile forces in longitudinal direction of the sealing stopper, but it also further improves the antitorsion protection already provided in general at the connecting mandrel through the interfacial adhesion. With this, considerable “safety reserves” are available, which will prevent a separation of the components even in case of a relatively ungentle and rough handling of the sealing stopper.
Joints based on frictional connection can, as a rule, be detached again in a non-destructive manner by applying a sufficient high force, exceeding a certain minimum value. For the desired application, the enclosure of the handle cap and the sealing body at its end provided for being inserted into the enclosure are preferably dimensioned in relation to each other such that this minimum force clearly exceeds the forces occurring through mechanical stress in the usual everyday use of the stopper. Analogously to this, the cross-section of a holding channel, for example of the type of a substantially cylindrical drill-hole, possibly existing already in the sealing body prior to joining the individual components, is correspondingly smaller than the connecting mandrel to be inserted. In this way, it is guaranteed that the closing and in particular the subsequent manual opening of a bottle will not lead to a detachment of the joint or even to a separation of the components of the stopper. This requires that the insertion of the connecting mandrel when manufacturing the stopper is only possible with a relatively increased expenditure of force, which can, however, easily be realized by mechanical devices.
Expediently, the connecting mandrel and the associated holding channel are arranged centrically, so that the forces acting on the handle cap during opening are transmitted uniformly to the sealing body and no undesired lever action occurs, which might reinforce the torsional torques possibly acting on the connecting mandrel and thus even cause its breakage.
To increase the strength of the joint based on a frictional connection, the connecting mandrel is advantageously provided with a number of enlargements, which perpendicularly to the axis of the mandrel penetrate into the resilient material of the sealing body, thus reinforcing the effect of the resilient deformation. The enlargements can be designed as peripheral bulges. In view of a particularly low expenditure of manufacture, however, a flat design, extending in each case in one radial direction, has proved to be advantageous. As far as the handle cap with the connecting mandrel is manufactured by an injection-molding method, the injection-molding die can also be particularly simple.
To facilitate the insertion of the connecting mandrel into the resilient sealing body when the stopper is manufactured, the enlargements on the connecting mandrel are preferably designed in such a way that they taper in the direction of its top. In an advantageous embodiment, this tapering is continuous, so that a catching is avoided when the mandrel is moved in inserting direction.
When attempting to move the connecting mandrel in reverse direction, however, such a catching is desired as it contributes to further increasing the strength of the joint. For this reason, a number of enlargements at the top of the connecting mandrel are preferably designed as snap-in hooks, which may have, in the direction of the side facing away from the top, sharp-edged projections. These can also be designed as barbs. In a particularly advantageous embodiment of the invention, several snap-in hooks are integrally formed onto the top of the connecting mandrel in a symmetrical manner. Due to the uniform distribution of the retention forces, a relatively small dimension of the snap-in hooks across the longitudinal direction of the connecting mandrel can in that case be chosen, which also facilitates the insertion of the connecting mandrel into the sealing body when the stopper is assembled.
When opening a bottle closed with the above-described stopper, considerable torques in relation to the bottle body might act upon the handle cap, in addition to pulling forces along the direction of withdrawal, because the person opening the bottle will possibly be tempted to turn or lever the stopper out of the bottle. To avoid a torsion of the connecting mandrel penetrating into the sealing body, the mandrel has advantageously a substantially cruciform cross-section, giving it additional stability and torsion resistance and protecting it against undesired breaking off.
A possible torsion of the handle cap in relation to the sealing body can further be inhibited by preferably providing the inside of the enclosure with a number of teeth engaging into the resilient material of the sealing body and reinforcing the catching effect.
In order to transmit any arising torques uniformly over the sealing body and thus stress the latter in a particularly homogeneous manner, all teeth as a whole form in an advantageous embodiment a continuous knurling.
The optimum choice of the ratio of dimensions regarding the above-described features depends on numerous details, in particular the type of the bottle to be closed and the materials used for the stopper. In general, however, for the case that, when the stopper is joined, the connecting mandrel is inserted into a sealing body which is free from drill-holes or the like, it has turned out to be expedient that the mean dimension of the connecting mandrel perpendicularly to its axis is 1/7 to 3/7, preferably approximately 2/7 of the diameter of the sealing body. If the sealing body is provided with a drill-hole for the connecting mandrel, the diameter of the hole should be maximally half of the mean diameter of the connecting mandrel, in order to achieve a high clamping effect and strength of the joint.
The length of the connecting mandrel should advantageously be ¼ to ¾, in particular approximately half the length of the sealing body
In view of the required mechanical stability of the composed stopper, the sealing body is preferably made of a synthetic material, in particular a thermoplastic elastomer. This choice of material also fulfills the requirements as to tightness, neutrality of taste and chemical harmlessness, as well as easy workability in a particularly advantageous manner.
For use in large quantities and a particularly low manufacturing expenditure, on the one hand, and for high strength and good grip, on the other hand, the handle cap is advantageously also made of a synthetic material, in particular high-density polyamide. Polyethylene or many other synthetic materials of corresponding strength and hardness could also be used.
Advantageously, the stopper is manufactured by inserting the connecting mandrel of the handle cap into the sealing body. Such an insertion process only requires a linear translatory motion of the two components relative to each other, which can be realized and controlled in a particular easy and cheap manner in particular by using automated or mechanical manufacturing methods. In a first advantageous variant of the method, a holding channel for the connecting mandrel can already exist in the sealing body prior to the assembly, which is extended or dilated by the subsequent insertion of the connecting mandrel. Such a holding channel can be produced in the sealing body for example by means of a drilling tool. In a particularly advantageous second variant, one can, however, also do without such a drill-hole. In this case, the top of the connecting mandrel deforms the sealing body, as soon as it hits the end surface of the sealing body. Only when the connecting mandrel moves forward relative to the sealing body “by force”, will the resilient material of the sealing body tear at the spot of impact, forming a holding channel surrounding the connecting mandrel. Surprisingly, it turned out that the initial deformation of the sealing body, when it is hit by the connecting mandrel, is most advantageous, as it leads to a contraction or reduction of the cross-section of the sealing body at the latter's end facing the handle cap. The sealing body deformed in this way can then be inserted relatively easily into the narrow enclosure of the handle cap. As soon as the connecting mandrel has reached its final position in the sealing body, the material of the sealing body, due to its resilient properties, tries to resume its original form and to undo the contraction or narrowing on the enclosure-side end of the sealing body. In this way, a particularly good clamping effect is achieved in the area of the enclosure. The above-described effect becomes very effective in particular when the connecting mandrel has a flattened or rounded top.
In an expedient development of the method, in particular for a mechanical or automated manufacture of the stopper, the handle cap is held and the sealing body is moved, in-side a guide tube centrally aligned with the connecting mandrel of the handle cap, in the direction of the handle cap and its connecting mandrel. To produce the compressive force necessary for joining, for example a pressure piston projecting into the guide tube can be provided, which acts upon the end of the sealing body facing away from the handle cap and which advances the sealing body until the connecting mandrel has completely penetrated into the sealing body. Advantageously, the guide tube slightly tapers towards the handle cap, so that the sealing body is additionally squeezed before it is pressed into the enclosure of the handle cap. In this way, the sealing body can be inserted even into a relatively narrow enclosure, which results in an extremely firm fit.
The advantages achieved with the invention consist in particular in the fact that the purposeful creation of a frictional connection between the connecting mandrel integrally formed onto the handle cap and the resilient sealing body as well as between the sealing body and an enclosure provided on the handle cap results in a stopper for repeated closing of a bottle, which is safe from the point of view of food engineering, easy to manufacture and extremely stable against mechanical influences. This stability, which is in principle already guaranteed by a suitable dimensioning of the elements joined to each other as well as by the choice of suitable materials, is further increased by the enlargements provided on the connecting mandrel, preferably designed in the form of snap-in hooks, and the knurled design of the enclosure on the handle cap, so that the consumer is given an overall impression of high quality, even after repeated use of the stopper. Such a press fit between handle cap and sealing body allows in addition a particularly simple assembly of the composite stopper by inserting the connecting mandrel with corresponding expenditure of force into the sealing body. By abandoning glue and other techniques for the creation of a material engagement, the associated operations and requirements imposed on the production installations can be omitted. Handle cap and sealing body can, furthermore, be manufactured independently of each other. In principle, a handle cap made of synthetic material can also be combined with a sealing body made of a natural material, so that, depending on the field of application, a relatively great freedom of choice of the material is given.

BRIEF DESCRIPTION OF THE DRAWINGS

One embodiment of the invention will be explained in detail by means of a drawing, in which:
FIG. 1 is a perspective view of the stopper with a sealing body and a handle cap;
FIG. 2 is a sectional view of the stopper of FIG. 1;
FIG. 3 is a perspective view of the handle cap of FIG. 1; and
FIG. 4 is a top view of the handle cap of FIG. 1, lying on its flat top cover side.

DETAILED DESCRIPTION

Identical parts are marked with identical reference numbers in all figures.
The stopper 2 according to FIG. 1 in the so-called “bartop” version serves to close a spirit bottle. It can, however, also be used, for example, for vinegar or syrup bottles or the like. It comprises a sealing body 4, which is pressed into the pouring opening of the bottle, sealing it due to its resilient property, and a relatively hard handle cap 6, making it possible to withdraw the stopper 2 from the bottle without using any aids and to insert it again after use. A connecting mandrel 8 is integrally formed onto the handle cap 6, as shown in FIG. 2 in cross-section, penetrating into the sealing body 4, whereby the connecting mandrel 8 is clamped in a holding channel 10 of the sealing body 4.
To provide for a long durability, the stopper 2 is designed for a particularly stable and durable connection between the sealing body 4 and the handle cap 6, which is achieved, on the one hand, without the use of glue, which might diffuse through the material of the sealing body 4 into the interior of the bottle and deteriorate its contents, and, on the other hand, without the application of expensive manufacturing techniques. Instead, a frictional connection is provided between the handle cap 6 and the sealing body 4. For this purpose, firstly, the material of the handle cap 6 and the material of the sealing body 4 are matched. Secondly, the connecting mandrel 8 integrally formed onto the handle cap 6 has a shape and dimension suitable for a high clamping effect.
In the exemplary embodiment, the connecting mandrel 8 has a length of approx. 20 mm and a mean diameter of 6.5 mm, whereas the sealing body 4 has a length of approx. 28 mm and a diameter of 19.0 mm. These dimensions guarantee that the connecting mandrel 8 can be inserted with a sufficiently high expenditure of force, under resilient deformation of the sealing body 4, into the sealing body 4, but that the joint created through surface pressure is sufficiently strong to avoid a separation of the components under proper use of the stopper 2 and the forces occurring thereby. A pilot-drilling of the sealing body 4 is not necessary. Rather will the holding channel 10 be created through the insertion of the connecting mandrel 8. The connecting mandrel 8 is arranged centrally to the axis of the stopper 2, so that the forces acting upon the handle cap 6 when opening and closing a bottle are uniformly transmitted to the sealing body 4.
Furthermore, a number of enlargements 12 are integrally formed onto the connecting mandrel 8. Their lateral projection over the basic profile of the connecting mandrel 8 varies between 1 and 2 mm. They lead to an additional deformation of the resilient sealing body 4 when the connecting mandrel 8 is inserted into it and thus increase the strength of the frictional joint.
It is a common feature of all enlargements 12 that they taper, in the shape of an arrow, in the direction of the flattened top 13 of the connecting mandrel 8, as is evident from the sectional drawing in FIG. 2. These tapered portions 14 reduce the compressive forces necessary for assembling the stopper 2 during its manufacture, because the sealing body 4 is continually pre-expanded during insertion of the connecting mandrel 8.
In the direction of the side facing away from the top 13, the enlargements 12 are provided with sharp-edged projections 16 and, therefore, have the shape of snap-in hooks. They can also be designed as barbs with a projecting portion facing away from the direction of insertion, but for achieving a good snap-in effect, securing the joint based on a frictional connection against loosening, the shape shown in FIG. 2, which is easier to manufacture, is quite sufficient. In the exemplary embodiment, a total of four snap-in hooks can be seen, which are opposite each other in pairs and symmetrically. If necessary, further snap-in hooks can be integrally formed onto the connecting mandrel 8 for a better distribution and take-up of the retention forces.
As is evident from the view shown in FIG. 3, the enlargements 12 are substantially flat and lie in a plane extending radially to the axis of the connecting mandrel 8. This shape can be manufactured in a particularly simple and cheap manner. However, other designs, for example in the shape of peripheral bulges, are also possible.
The top view in FIG. 4, showing the handle cap 6 lying on its flat top cover side, illustrates the substantially cruciform cross-section of the connecting mandrel 8, which gives it a greater torsion resistance in comparison with a circular cross-section.
The handle cap 6 includes an enclosure 18 for the sealing body 4, whose free cross-section of about 18.9 mm is slightly smaller than the cross-section of the non-enclosed sealing body 4 of 19.0 mm. The sealing body 4 is pressed into the enclosure 18, which gives the stopper 2 additional stability. The width of the enclosure 18 is dimensioned such that the enclosure 18 of the handle cap 6, which after insertion of the stopper 2 into the neck of the bottle lies on said neck of the bottle, is laterally flush with the body of the bottle. However, realizations with a lateral projection of the handle cap 6 over the neck of the bottle are also imaginable. To increase its grip, the outside of the handle cap 6 is expediently provided with grooves or elevations.
A possible torsion of the sealing body 4 relative to the handle cap 6, which is already aggravated by inserting the connecting mandrel 8 into the sealing body 4 with frictional connection and by pressing the sealing body 4 into the enclosure 18 with frictional connection, is completely excluded, with the torques usually arising in everyday use, by means of the teeth 20 arranged on the inside of the enclosure 18. In the present example, all the teeth 20 as a whole, projecting approx. 0.5 mm into the sealing body, form a continuous knurling 22, which constitutes a very efficient antitorsion protection.
The sealing body 4 can traditionally be made of natural cork or a similar natural cellular body, with which usually a good sealing effect is achieved. However, this material may have a negative effect on the contents stored in the bottle, through release of flavoring agents. It addition, it is relatively expensive, due to the limited availability of the regenerative natural cork material. Therefore, the sealing body 4 in the exemplary embodiment is made of a synthetic material, namely a thermoplastic elastomer. This material is neutral as to taste, easy to process, and possesses particularly favorable mechanical properties, in view of the joint with the handle cap 6, also made of a synthetic material, namely polyamide of high density and high rigidity, effected by frictional connection. In particular, polyamide 6.6 is provided as an advantageous material for the handle cap 6.
Therefore, the stopper 2 is easy to manufacture, safe from the point of view of food chemistry, and extremely stable against mechanical stress, so that a repeated reliable re-closing of the opened is possible without problems.

Claims

1-15. (canceled)

16. A stopper for closing a bottle, the stopper comprising:

a handle cap;

a sealing body being resilient relative to the handle cap;

a connecting mandrel integrally formed on the handle cap and penetrating into the sealing body, wherein the handle cap includes an enclosure for the sealing body having a free cross-section is smaller than a cross-section of the sealing body, the handle cap being firmly connected with the sealing body through a first frictional connection between the connecting mandrel and the sealing body surrounding it, as well as by a second frictional connection between the enclosure and the sealing body.

17. A stopper as recited in claim 16, wherein the sealing body includes a holding channel and the connecting mandrel is dimensioned relative to the holding channel such that the first frictional connection develops when the connecting mandrel is inserted into the holding channel, taking into account a resilient property of the sealing body.

18. A stopper as recited in claim 16, wherein the connecting mandrel includes a plurality of enlargements that engage into the resiliently deformable sealing body perpendicularly to an axis of the connecting mandrel.

19. A stopper as recited in claim 18, wherein at least one of the plurality of enlargements tapers in a direction of a top of the connecting mandrel.

20. The stopper as recited in claim 18, wherein the enlargements form snap-in hooks.

21. The stopper as recited in claim 16, wherein the connecting mandrel has a cruciform cross-section.

22. The stopper as recited in claim 16, wherein the enclosure includes a plurality of teeth engaging into the sealing body.

23. The stopper as recited in claim 22, wherein the teeth are formed as a continuous knurling of the enclosure.

24. The stopper as recited in claim 23, wherein a mean dimension of the connecting mandrel perpendicularly to its axis is from to 1/7 to 3/7 of a diameter of the sealing body.

25. The stopper as recited in claim 16, wherein a length of the connecting mandrel is to ¼ to ¾ of the sealing body.

26. The stopper as recited in claim 25, wherein the connecting mandrel has a flattened top.

27. The stopper as recited in claim 16, wherein the sealing body includes a synthetic material.

28. The stopper as recited in claim 27, wherein the synthetic material is a thermoplastic elastomer.

29. The stopper as recited in claim 16, wherein the handle cap includes a synthetic material of high strength.

30. The stopper as recited in claim 16, wherein the synthetic material is a polyamide.

31. A method for manufacturing a stopper according to claim 16, comprising:

inserting the connecting mandrel of the handle cap into the sealing body and generating a holding channel for the connecting mandrel in the sealing body.

32. The method as recited in claim 31, further comprising moving the sealing body towards the handle cap within a guiding tube conically tapering in a direction of the handle cap.