EP1924506B1 - Closure apparatus for closed containers composed of a plastic film - Google Patents

Abstract

A closure device attachable above a location of a closed receptacle, comprising a stopper portion with a cylindrical pour-out spout connected or connectable to the receptacle, and a screw cap screwed onto the lower part, and a cylindrical piercing element that in the axial direction is open at both sides and is displaceably mounted in the lower part, wherein catch portions move the piercing element helically downwards when screwing off the cap for the first time, wherein the piercing element is equipped with at least one cutting element.

Description

The present invention relates to an attachable over a point of a closed container closure device made of plastic, consisting of a bung-shaped base with cylindrical spout which is connected to the container or connectable, and a screw cap which can be screwed onto the lower part, and a cylindrical piercing, the is open on both sides in the axial direction and is slidably mounted in the lower part, wherein in the screw cap entrainment means are the screw on the first screw-down movement of the screw the piercing screw down, the piercer is equipped with at least one cutting element.

Closure devices of the type mentioned above are known in numerous embodiments from various documents and available on the market. Of the oldest documents that describe such a closure device of the type mentioned, this is the side US-A-5,020,690 considered. This document describes a closure device of the type mentioned above, which only differs from this in that the entrainment means in the screw cap only serves to exert an axially extending movement of the piercer. Correspondingly, therefore, the piercer 3 does not perform any helical movement, but also exerts only an axial translational effect in accordance with the action of the entrainment means. The rotation required to achieve a screwing movement is correspondingly prevented by cams on the piercer, which are arranged on corresponding guides in the bung-shaped lower part, namely in its spout.

The cutting element is in the mentioned embodiment according to the US-A-5,020,690 formed from a variety of teeth. Absolutely comparable is a solution, which from the US-A-5,141,133 is known. Here, the cutting element consists of a continuous circumferential, gapless series of adjacent teeth, so that the piercing has practically the shape of an annular saw blade. This solution, which from the US-A-5,141,133 is known, but otherwise has the same drive system as the previously described embodiment according to the US-A-5,020,690 ,

Consequently, in all of the aforementioned documents, the piercers have a pure axial translational motion without any rotation. That is, the piercer is literally pushed through the packaging material that makes up the container. For this purpose, it should be noted that all closure devices to date, which correspond to the type mentioned above, have been mounted on containers which are made of a multilayer material and consisting essentially of paper and / or cardboard with extra exceptionally thin layers of plastic and / or aluminum. The cutting elements, which consist essentially of a plurality of teeth, as already mentioned, could only make a perforation with their tips. In order for such closures to be functional at all, the containers had to have a partial punching or embossing, by which the packaging material was already greatly weakened. Such a pre-punching means that the cylindrical spout of the bung-shaped lower part must be mounted as exactly as possible covering this pre-punching. This is technically extremely difficult, in particular since the attachment of the bung-shaped lower part can not be placed mechanically connected exactly, but rather, because the bung-shaped lower part must be glued to the packaging, there is almost inevitably a deviation at the required production speeds. Accordingly, the mass were designed so that a certain tolerance is allowed. Thus, according to the pre-punching dimensioned slightly smaller than the clear diameter of the cylindrical spout. Despite these precautionary measures, the reject rate for closures of this type was extraordinarily high. Not only the inevitably unrealizable accuracy, which could not be met, caused these committees, but also the problem of the corresponding adhesive dosage to glue the bung-shaped base to the foil caused these rejects. Even slight excess amounts of adhesive cause the adhesive to be partially squeezed towards the center during printing and thus this adhesive gets exactly into the area of the pre-punching. As soon as the adhesive has hardened, a correct and perfect separation of the packaging material by means of the piercer is no longer feasible. Logically, there is also a problem when too little adhesive is used, because then the liability of the bung-shaped base on the film-like packaging material is insufficient and when unscrewing the piercing practically repelled only the film of the packaging material from the flange of the spout.

After this problem has been recognized, closure devices of the aforementioned type have been realized in which the piercer is no longer in a pure translatory movement was driven, but as mentioned above, the piercer was now moved downwards helically. For this purpose, corresponding entrainment means were provided in the screw cap, which act together with appropriately acting entrainment means in the piercer. Solutions of this kind are for example from the documents US-A-5,297,696 . US-A-5,482,176 and the US-A-5,960,992 known. Of course, all these solutions also demanded a pre-punching of the film material from which the container is made, and also in these solutions, the cutting means were always realized as a continuous wreath of teeth. Thanks to the now performed screwing these teeth practically performed a sawing. In addition, a certain eccentric attachment of the closure device relative to the pre-punching was less pragmatic, since the teeth rim in the eccentricity usually at least once, but usually twice the pre-punching crosses and thus at least one tooth can penetrate here and can make the perforation of the plastic film layer. Since the plastic is embedded, this can not expand more than just in the narrow slit-shaped area of the pre-punching, which is only a few hundredths of a millimeter. Thus, on the one hand, the teeth were able to cut through the paper / cardboard layers in the manner of a saw and, as soon as the teeth entered the plastic film, perforate them. The large number of teeth had been considered advantageous, as a result, a variety of perforations.

In fact, however, it has been found that a plurality of perforations per se give no advantage. Rather, it has been shown that a large number of teeth automatically means that these teeth must be relatively weak. While this is hardly relevant to the perforation per se, as long as the teeth are sharp, it has been found that the saw-like severing of the much thicker main layers of paper and cardboard results in these teeth being less sharp on the one hand and surrounded by fibers on the other hand are what has the same effect, namely a lower Perforationsfähigkeit.

On the basis of this knowledge, further developments have been made in which, on the one hand, the number of teeth has been reduced and, on the other hand, the shape of the teeth has been designed differently. For example, from the EP-A-1'415'926 a solution with all the same high, but unevenly distributed around the circumference teeth known. Finally, according to the US-A-6,279,779 discloses a closure device with a piercer having only a single tooth. This tooth is designed accordingly strong and has different surfaces on with different effects. Thus, the tooth has a sharp-edged angular area, which is the perforation serves, as well as a cutting area. Thanks to its thickness, it also has a deflecting function, but this deflecting function is realized by a separate displacer, which is also located at the piercer. The one-tooth version has clearly not proven. The processes of cutting through the carton, perforating the plastic film portion and cutting the entire material and finally folding away the cut-out part have not been optimized in a single element.

The documents described in detail earlier, which show closure devices with a cylindrical piercing device, in which the entire lower piercing edge is provided with a multiplicity of teeth of the same height, meant that practically all teeth also reach the film to be pierced at the same time. But this increases enormously the force required to cut through the plastic films. The elasticity of the film therefore unfortunately does not lead to the desired effect that the impact of the teeth, the perforation is cut almost equal to the touch of a soap bubble. To avoid the mentioned negative effect, the JP-A-11-171233 a solution with a plurality of teeth, all of which are arranged at different heights. This reduces the force required to cut through the film.

As already mentioned, all previously known and available on the market closure devices of the type mentioned are designed constructively for a packaging material, which as mentioned consists of mixtures of different materials and in particular contains a large proportion of paper and cardboard. Such packaging material has a corresponding strength, which is desirable in certain cases, but in cases where in particular the waste volume is to be reduced, as well as other properties not to be detailed here are to be achieved, is packaging material, which is essentially only a plastic film and only has one or more additional barrier layers of other materials, these barrier layers in the range of several microns in thickness, for such materials, all previously known closure devices are completely unsuitable.

The WO-A-02/28728 proposes a closure device which discloses all features of the preamble of claim 1.

It is therefore an object of the present invention to provide a closure device of the type mentioned above, which is particularly suitable for soft packaging while avoiding the previously known problems, which consist practically of a single plastic film with or without barrier layers.

This object is achieved by a closure device according to the preamble of claim 1, which is characterized characterized in that three cutting elements are arranged distributed over the circumference of the lower edge, wherein the cutting elements are teeth and the distance of the tips of the first tooth to the second tooth on the circumference of the size X and the distance of the tip of the second tooth to the third tooth, the size Y, while the distance of the tips of the third tooth to the first tooth is Z, and each having a circumferential stiffening shoulder associated therewith, wherein the stiffening shoulder on two teeth in the cutting rotational direction advances the tooth following a third tooth in the cutting direction of that tooth is arranged, each shoulder with the associated tooth is designed to merge into each other, and further that the tips of all three teeth at the same height are spaced from the lower edge and that the closed, openable container is made of a single or multi-layer plastic film.

Further advantageous embodiments of the subject invention are set forth in the dependent claims and their meaning will become apparent from the following description.

Figur 1

eine Aufsicht auf die Verschlussvorrichtung von unten auf den spundförmigen Unterteil, mit darin vollständig eingeschraubtem Durchstosser;

Figur 2

eine dreidimensionale Ansicht der Verschlussvorrichtung unter Weglassung der Schraubkappe, bei teilweise ausgeschraubtem Durchstosser und

Figur 3

dieselbe Verschlussvorrichtung in der Ansicht wie in Figur 2 mit vollständig bis zur Gebrauchslage ausgeschraubtem Durchstosser.

Figur 4

zeigt schliesslich eine schematische Ansicht des Durchstossers in seiner Abwicklung, zur Verdeutlichung der erfindungsgemässen Anordnung der drei Schneidelemente.

In the accompanying drawings, a single, preferred embodiment of the subject invention is shown in detail and explained with reference to the following description. It shows:

FIG. 1

a plan view of the closure device from below on the bung-shaped lower part, with completely screwed through piercer;

FIG. 2

a three-dimensional view of the closure device with omission of the screw cap, with partially unscrewed piercers and

FIG. 3

same closure device in the view as in FIG. 2 with completely unscrewed to the position of use Durchstosser.

FIG. 4

finally shows a schematic view of the piercer in its development, to illustrate the inventive arrangement of the three cutting elements.

In the accompanying drawing, as already mentioned, a single, preferred embodiment model is shown, wherein the here for the invention, no new aspects resulting screw cap has been omitted. With regard to the configuration of the screw cap is expressly to the publication WO 03/002419 referenced, in which a screw cap is shown, which has the reference numeral 4 and has a top surface 40, on the underside of an annular wall 43 is formed, which in turn on its inside, ie for Directed center toward, driver elements 44 which cooperate with corresponding ratchet-shaped driver elements on the piercer. For the present invention, which essentially relates to the particular configuration of the piercer, it is thus assumed that this piercing device is equipped with a screw cap, which at least with respect to their functional parts of the embodiment according to the screw cap in the WO 03/002419 equivalent.

In addition to the screw cap, which is not shown here as already mentioned, the closure device, which is denoted overall by 1, additionally comprises two further parts, namely a bung-shaped lower part 2 and a cylindrical piercing body 3 mounted thereon in a screw-binding manner the use of three separate elements, the screw cap, although only hinted, in the FIG. 1 exists denoted by the reference numeral 4. In the FIG. 1 the assembled closure device 1 is visible from below with a view of the bung-shaped lower part 2, wherein the cylindrical piercing 3 is shown in the fully screwed position. The screw cap would be seen here with a view of the inside of the top surface 41, and the driver elements, which are radially inwardly resilient post, are designated 42. These driver elements 42 are designed so that they Screwing the screw cap 4 take the piercer 3, wherein the piercing 3 is placed in a screwing, in which the piercing 3 is moved from the bung-shaped lower part 2 toward the container, and the piercer 3 thus cuts through the film of the package. This screwing direction is shown by the arrow F. When rotated in the opposite direction, the screw cap 4 is closed. At the first opening, in which the screw cap 4 is rotated in the direction F, the piercing 3 is moved to an end position, as shown in the FIG. 3 is shown. In that position, then the driver 42 of the screw cap 4 are no longer in operative connection with the piercing 3, so that the piercer 3 remains in the end position, when then the screw cap 4 is rotated back in the opposite direction to the arrow F. After the first operation of the closure device 1, this works like an ordinary screw on a bung-shaped spout.

With regard to the following explanations, which relate to the bung-shaped lower part 2, is particularly to the FIGS. 1 and 2 directed. The bung-shaped lower part 2 has two main components, which are integrally connected to each other made in one piece, namely a cylindrical tube section 20, which forms the Ausgussspund, and a connecting flange 22 arranged thereon at the end. The connecting flange 22 serves the adhesive or Welded connection of the closure device 1 with the packaging, not shown here, which consists of a single or multi-layer plastic film as already mentioned. If the bung-shaped lower part 2 is to be welded to the packaging, the underside 25 can be provided with energy-conducting ribs 26, which are only hinted here in the FIG. 1 are drawn. Further, the terminal connecting flange 22 may be provided with an optional orientation notch 23 which may be inserted only in the FIGS. 1 and 3 is drawn. The optional orientation notch 23 merely serves as an orientation aid in a mounting device. Thanks to the orientation notch 23, a positioning that can be brought radially into a specific angular position is thus possible. Depending on the design of the mounting device, this may be advantageous, but by no means must be present.

The cylindrical tube section 20 or the pouring spout has an external thread 21 arranged on its cylindrical outer surface, which serves for connection to the screw cap 4. This external thread is preferably designed as a fine thread, so that the screw cap can be pressed directly into the assembly without screwing, the here not apparent internal thread of the screw cap, which can be ratcheted together with the external thread 21 on the spout 20 ratchet. The cylindrical pipe section 20 also has a Internal thread 24, which only in the FIG. 1 Suggestively recognizable as a two-start internal thread is designed. It does not matter to the invention whether this internal thread 24 is designed to be catchy or more continuous.

The elements which are particularly essential to the invention are recognizable on the piercer 3, and their description and explanation are particularly based on the Figures 3 and 4 directed. The cylindrical piercer 3 has a cylindrical tube section 30 which is completely open on both sides. The cylindrical tube section 30 has an external thread 31, which cooperates with the internal thread 24 in the cylindrical tube section 20, the spout. In the FIG. 3 is the piercing 3 drawn in its lowest position, so that the internal thread 24 in the spout 20 is visible. The piercer 3 has an annular casing wall 32, the lower end face 33 forms as a mounting surface for the integrally formed thereon three cutting elements 34,35,36. The cutting elements 34,35,36 are thus integrally formed over the end face 33 with the jacket wall 32 of the cylindrical pipe section 30. The three cutting elements each have a tooth. The cutting element 34 has a tooth 340, the cutting element 35 a tooth 341, and the third cutting element 36 a tooth 342. Also in the FIG. 3 the screwing direction is shown by the arrow F. Every tooth 340-342 has a tip. Here, the tips 343 of the tooth 340 and the tip 344 of the tooth 341 are configured as perforating tips, while the tip 345 of the tooth 342 is designed both as a perforating tip or, as shown here, as a pressure tip 345. All tips 343-345 lie in one plane and are thus all located equidistant from the lower end face 33 of the shell wall 32 away. This ensures that in a Aufschraubbewegung, ie in the direction of arrow F, in which the closure is opened or removed the screw cap 4 and the cylindrical piercing 3 moves in the direction of the container, come to rest simultaneously on the film of the package. In this case, a tension of the film to be cut is thus effected in a first step. Only when this tension is built up, then at least with the two perforation tips 343 and 344 is a perforation of the film. Each tooth 340-342 has a corresponding cutting edge 346-348. The cutting edges 346-348 are arranged to act upon rotation in the direction of the arrow F. While the cutting edge 346 of the tooth 340 and the cutting edge 347 of the tooth 341 each extend from the corresponding tip 343 and 344, respectively, to the lower end surface 33 of the cylindrical tube section 30, the cutting edge 348 shortens as a cutting edge from its tip 345 to that to be described stiffening shoulder. Each tooth 340-342 is associated with a stiffening shoulder 350-352. The two stiffening shoulders 350 and 351 are arranged in the cutting direction of the corresponding associated teeth 340 and 341 trailing, while the stiffening shoulder 352 is arranged in the cutting direction leading the corresponding tooth 342. The leading stiffening shoulder 352 is especially extended. The stiffening shoulders 350-352 serve to reinforce the teeth 340-342 so that they do not fold over when building the tension on the film to be cut. In particular, since the tooth 342, which has a further function as described below, should absorb more forces, the corresponding reinforcing shoulder 352 is made longer.

As from the settlement in the FIG. 4 As can be seen, the distance between the first tooth 340 and the second tooth 341 is the distance X, while the distance between the second tooth 341 and the third tooth 342 is the distance Y, and finally the distance between the third tooth 342 and the first tooth Here, it can be seen that the distances X and Y are shorter than the distance Z. This is to ensure that in particular the cutting elements 34 and 35 perform the Hauptschneidtätigkeit while the cutting element 36 performs a cutting and displacement action. In principle, it is possible, in particular the distances X and Y in the Size the same. However, this is not mandatory, but merely represents an optimization question, which essentially depends on the choice of material.

The piercer 3 has on its inner surface located toward the center two driving edges 37 and 38 which cooperate with the driver elements 42. Preferably, one of the two Mitnehmerkanten 37 laid so that it is aligned with the tip 343 of the cutting elements 34. These driving edges form a thickening in the radial direction and stiffen the tooth accordingly, so that it is stiffened against deformation. The second driver edge 38 is located in the piercer 3 approximately diametrically opposite the first driver edge 37.

Between each two adjacent cutting elements 34-36 gaps remain 360. These gaps 360 are preferably all the same size. This facilitates the intervention of corresponding fingers of a mounting device, but have no influence on the actual cutting function of the piercing device.

Also, the inclinations of the cutting edges 346-348 may be different. In the embodiment shown here, the cutting edges 346 and 347 are made equal in inclination, while the shortened cutting edge 348 of the cutting element 36 takes a flatter course.

Each of the tips 343-345 thus has a respective cutting edge 346-348, while the edges remote from the cutting edge are referred to as trailing edges. The angle which the respective cutting edge and the associated trailing edge enclose with each other at the corresponding tip is denoted by α. Preferably, this angle is less than 150 °. In a preferred embodiment, in particular at the tips 343 and 344 as shown here, the angle α is 90 °. Again, this is not a compulsory rule, but merely an experimentally determined preferred size.

As already mentioned, the underside 25 of the flange 22 may be provided with energy-conducting ribs 26. Of course, these power-conducting ribs 26, which are an embodiment of energy-conducting means, can be configured differently. Again, experiments have shown that two embodiments are particularly suitable, namely on the one hand those in which these energy directing means are formed from perpendicular projecting from the flange ribs, which are arranged either radially outwardly from the inside out or concentric. Of course, these two versions can also be combined. In the case of the concentrically arranged energy guide ribs, at least the innermost energy guide rib will be arranged approximately in alignment with the inner edge of the discharge opening of the bung-shaped lower part.

LIST OF REFERENCE NUMBERS

1

closure device

2

bung-shaped lower part

3

cylindrical piercer

4

screw cap

41

cover surface

42

entrainment

F

unscrewing direction

20

cylindrical pipe section, spout

21

External thread for connection with screw cap 4

22

terminal connection flange

23

optional orientation notch

24

two-start internal thread

25

bottom

26

Energieleitrippen

30

cylindrical pipe section

31

external thread

32

Mantle wall of the piercer

33

lower end face of the shell wall

34-36

three cutting elements

340-342

teeth

343-345

Tips of the teeth

343.344

with perforating tip

345

with pressure tip

346-348

Cutting edge of the teeth

350-352

reinforcing shoulders

350.351

trailing in a cutting direction

352

leading in a cutting direction

X

Distance between peak 343 and 344

Y

Distance between peak 344 and 345

Z

Distance between peak 345 and 343

37.38

entrainment

360

Gaps

353-355

trailing edge

α

angle

Claims (12)

1. A closure device (1) made of plastic which can be affixed over a point on a closed container (B) and consists of a plug-shaped lower part (2) with a cylindrical discharge plug (20), which is or can be connected to the container and a screw cap (4) which can be screwed onto the lower part (2), as well as a cylindrical piercer (3) which is open on both sides in the axial direction and is displaceably mounted in the lower part, wherein entraining means (42) are present in the screw cap (4), which move the piercer (3) down in the manner of a screw in the event of the first unscrewing movement of the screw cap (4), wherein the piercer (3) is equipped with at least one cutting element (34-36),
   characterized in that three cutting elements (34-36) are arranged distributed over the circumference of the lower edge, wherein the cutting elements (34-36) are teeth and the distance from the tip of the first tooth (340) to the second tooth (341) on the circumference has the value X and the distance of the tip of the second tooth (341) to the third tooth (342) has the value Y, while the distance from the tip of the third tooth (342) to the first tooth (340) is Z, and in that each is assigned a reinforcing shoulder which runs in the circumferential direction, wherein the reinforcing shoulder is arranged on two teeth after the tooth in the cutting rotational direction and is arranged on a third tooth ahead of this tooth in the cutting direction, wherein each shoulder is constructed with the assigned tooth such that they merge into one another, and in that further, the tips of all three teeth are arranged at the same height, distanced from the lower edge, and in that the closed container which is to be opened is produced from a single-layer or multilayer plastic film.
2. The closure device according to Claim 1, characterized in that the distances X and Y are identical.
3. The closure device according to Claim 1, characterized in that a gap is present between in each case two units of tooth with shoulder.
4. The closure device according to Claim 3, characterized in that the width of all three gaps is identical.
5. The closure device according to Claim 1, characterized in that each tooth has a cutting edge and a following edge, wherein the two edges comprise an angle α of less than 150°.
6. The closure device according to Claim 5, characterized in that the angle α is at most 90°, wherein the angle α on one tooth is smaller than in the case of the two others.
7. The closure device according to Claim 1, characterized in that the height of the reinforcing shoulder corresponds to at least one third of the height of the tooth from the lower edge of the cylindrical piercer (3) to the tip of the tooth and at most two thirds of this height.
8. The closure device according to Claim 1, characterized in that at least one entraining edge (37,38) is present in the cylindrical piercer (3), which interacts with entraining means (42) on the screw cap (4), wherein the entraining edge has a ramp-shaped construction and its vertical orientation runs radially orientated with respect to the piercer axis, while the ramp edge runs parallel to the piercer axis.
9. The closure device according to Claim 8, characterized in that one entraining edge (37) is located such that it runs through the tip (343) of a tooth (34).
10. The closure device according to Claim 1, characterized in that the plug-shaped lower part (2) has a flange which is provided with energy transmission means on its surface which faces the container.
11. The closure device according to Claim 10, characterized in that the energy transmission means are ribs which stick out perpendicularly from the flange and, with respect to the centre, are arranged in a radially flush manner and/or running concentrically.
12. The closure device according to Claim 10, characterized in that the energy transmission means are ribs which stick out perpendicularly from the flange, wherein at least one rib is at least approximately flush with the inner edge of the discharge opening of the plug-shaped lower part (2) .

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