EP1976764B1 - Closable opening device produced with a semifinished product and method of fitting the same - Google Patents

Abstract

A pouring nozzle with a flange and an internal thread and an external thread, and also a cutting element having an upper rim and a lower rim formed with teeth. A screw cap with catches acts on catches of the cutting element. To make fitting easier, the cutting element and the pouring nozzle are produced as a one-piece semifinished product, wherein the cutting element is connected to the lower rim by weakened bridges so that the lower rim of the cutting element lies in a plane with the upper rim of the pouring nozzle and the teeth are protected in the pouring nozzle. This structural design allows an easy fitting which also reduces the reject rate.

Description

The present invention relates to a closable opening device for a sealed package containing a flowable medium, the device having a spout with flange, which is provided with an internal thread and an external thread, and a cylindrical cutting element, which with an upper, a planar surface defining edge is provided, while the lower edge is provided with a tooth or a plurality of teeth, and whose inner circumferential surface is provided with radially acting drivers, which cooperate with drivers in a screw cap, so that the cutting element pierces the packaging in a screwing motion, wherein the spout with flange and the cylindrical cutting element are made as a one-piece semi-finished product.

A closable opening device of the type mentioned is from the EP-A-1'088'764 known. Here, a principle is applied, which is common in the closure technique, by multipart fasteners so manufactures that two parts are arranged one above the other and injected together via predetermined breaking points connected together in one piece. In this case, on the one hand the cost of tools is reduced and on the other hand simplifies assembly, since the interconnected via predetermined breaking points parts are already arranged in their precisely aligned relative position to each other and thus only need to be pushed together. This technology, which is known per se, has also been used earlier for the closures of interest here and is also known, for example, from EP-A-1'084'060. The opening device disclosed here differs from the first-mentioned opening device according to EP-A-1'088'764 in that the cutting element has no plane surface at its upper end, but an inclined surface which is on a just such inclined inclined surface at the first operation the closure device rests and thus exerts a straight, acting perpendicular to the to be pierced packaging pure transverse force. This type of movement is in contrast to the movement of interest here according to EP-A-1'088'764, in which the cutting element is moved in a screwing movement through the package.

In both documents, a semi-finished product is disclosed, which is a one-piece production of a spout with a flange together with a cylindrical cutting element shows. The cutting element according to EP-A-2'084'060 has neither at the top nor at the bottom of a flat surface which is adapted to be circumferentially connected to an upper or a lower edge of the spout. Inevitably, therefore, a solution is disclosed here, in which the cutting element is made in an intermediate position within the spout via predetermined breaking points with the lower edge of the spout through predetermined breaking points as a semi-finished product.

In both solutions, however, the pre-assembly, in which the cutting element must be pushed into the spout, by no means as trivial as this may seem straightaway. The mentioned packages of laminates, on which the closing devices of interest are attached, contain at least one plastic film layer, which is problematic to cut, since the material has a high toughness and must be pierced accordingly in order to be cut at all. This requires that the teeth or the at least one tooth is correspondingly sharp and has sufficient strength. Would you now push the spout and the cutting element without appropriate special precautions simply applied by top and bottom applied pressure, so this would bend over the most delicate teeth, cancel or at least dull. As a result, the operation of the opening device is no longer guaranteed. To this, too avoid, must be correspondingly complicated. Mounting devices are used in which the semi-finished products are placed exactly positioned, only then to be pushed together. Such assembly is not only due to the system correspondingly expensive, but also the assembly speed is relatively low for a bulk and causes a high rejection.

In the FR-2 765 194-A a closure is disclosed with a spout with flange on which a lid is held over the spout by means of predetermined breaking point bridges. This is a finished product in which the user should first break off the lid and then screw it in and at the same time cut open a foil of the container.

Also no semifinished product shows the EP-0 385 603 A , Before use, the consumer should remove a lid from the closure and then manually manipulate a piercer by hand, destroying predetermined breaking point bridges that provide a temporary connection between the teeth and the spout.

Already from the documents WO 02/28728 and from WO 2004/083054 Closure devices are known in which via a cylindrical spigot with internal thread a piercer with spout thread via predetermined breaking point bridges are formed into a semi-finished product. In these solutions, the teeth of the piercer are not within the spout and the predetermined breaking points bridges are not defined in the orientation in the first case and in the second case, these run virtually vertically in the region of the slightly offset walls.

It is the object of the present invention to provide a closable opening device of the type mentioned above, wherein a semi-finished product is used, which can be mounted much more easily and inexpensively, without causing the teeth are affected, and without the a sealing surface forming upper edge of the spout is verletgt.

It is a further object of the present invention to provide a method by means of which the semifinished product of the newly created opening device can be mounted particularly inexpensively and at high speed. This object is achieved by a method having the features of patent claim 4.

The seemingly trivial solution is based on overcoming a prejudice of the skilled person. The solution chosen here, in which the cutting element is sprayed together with its lower edge at the top of the spout through predetermined breaking points, has so far been in the art as unsuitable considered, since the upper edge of the spout is intended to work together with an annular sealing bead on the inside of the cap. The attachment of predetermined breaking points in this area was considered unusable, since this causes defects at the top of the spout, and the experts was convinced that in this way the opening device of interest here is no longer sealing closed. Experiments have shown, however, that such a solution can be realized without creating a leaking opening device in the closed state. In particular, because the predetermined breaking points are designed according to claim 1, the remainder approaches that remain on the spout are so small that this does not affect the seal. Another solution not according to the invention would be that the annular sealing wall with the circumferential sealing bead formed thereon is made slightly longer, so that, in the closed state, it penetrates further into the spout of the spout. This implies that the cutting element should be pushed slightly deeper into the spout. This can be achieved by means of a method according to the dependent claim 6.

Figur 1

einen Vertikalschnitt durch ein Halbfabrikat in der Herstellungslage in der das Schneidelement über dem Ausgussstutzen über Sollbruchstellen gehalten ist.

Figur 2

zeigt dieses Halbfabrikat im montierten Zustand, und

Figur 3

zeigt die geschlossene Öffnungsvorrichtung im Zustand vor der Erstöffnung wiederum in einem Vertikalschnitt.

Figur 4

stellt schematisch eine Montagestation, die nach dem erfindungsgemässen Verfahren arbeitet, vereinfacht dar.

In the accompanying drawing a preferred embodiment of the subject invention is shown and their configuration and the method according to the invention are explained in the following description. It shows:

FIG. 1

a vertical section through a semi-finished product in the manufacturing position in which the cutting element is held above the spout through predetermined breaking points.

FIG. 2

shows this semi-finished product in the assembled state, and

FIG. 3

shows the closed opening device in the state before the first opening again in a vertical section.

FIG. 4

schematically illustrates an assembly station, which operates according to the inventive method, is simplified.

To explain the main components of the opening device, which is generally designated 1, is on the FIG. 3 directed. The opening device has the three main components, namely a spout 2 and a movably mounted therein cutting element 3 and the opening device occlusive cap 4. The two main components 2 and 3, so the spout and the cutting element are manufactured in one piece manufacturing technology and form a semi-finished product, which is denoted by 5 and in the FIG. 1 is shown on its own in the production position.

The semi-finished product 5, consisting of the spout 2 and the cutting element 3, facilitates the assembly of these two parts on the one hand, and on the other hand, the production of a semi-finished product significantly reduces the tooling costs. In addition, since it is not necessary to produce two separate parts, it goes without saying that the machine costs are also reduced.

The spout 2 is formed by a cylindrical tube section 20 which has a terminal flange 21 at its lower end. The cylindrical tube section 20 is provided on the one hand with an external thread 22 and on the other hand with an internal thread 23. The external thread 22 is designed here as a so-called fine thread, wherein the cross section of the thread has a rounded shape. This fine thread has the advantage that a aufzusetzende cap 4 can be pushed ratchet-like with relatively little effort, with the matching internal thread of the cap slides over the external thread 22. This makes it possible to mount the cap without performing a rotational movement, which is necessary because the cap itself has means that interact with the cutting element 3 so that a Rotation of the cap causes an opposite rotational movement of the cutting element 2.

Above the flange 21 but below the outer thread 22, one or more release means 24 are provided, which have the shape of radially outwardly directed fingers. These finger-shaped release agent 24 engage in the assembled state of the opening device below the lower edge of the cap 4 between predetermined breaking points, wherein the predetermined breaking points a guarantee strip, which is integrally formed on the lower edge of the cap 4 hold. During the first actuation of the opening device 1, the separating means 24 shear the predetermined breaking points of the cap 4 and thus separate the guarantee strip from the cap 4. The upper edge of the pouring spout 25 defines a planar surface which runs parallel to the flange 21. The internal thread 23 on the spout 2 has a substantially greater pitch than the fine thread 22 on the outside of the spout 2. The cross-section of this internal thread is trapezoidal. Thanks to this trapezoidal shape, once again the cutting element 3 can be pushed into the spout 2 with reduced resistance without the threads being destroyed.

The cutting element is designated overall by 3. It has a cylindrical tube section 30, in which an external thread 31 is inserted. This external thread 31 is form matched to the internal thread 23 of the spout 2 and meshes with this internal thread at the first operation of the opening device. The cylindrical tube section 30 has an upper edge 32 which defines a planar surface, which in turn is parallel to the plane defined by the flange 21. The lower edge of the cutting element 3 is designated 33. This lower edge 33 is located in the production position of the semi-finished product 5 at least approximately in the region of the upper edge 25 of the spout 2 and is integrally connected to this spout 2 in this state. The connection produce a plurality of predetermined breaking point bridges 34. In the FIG. 1 only a predetermined breaking point bridge 34 can be seen, since the predetermined breaking point bridges 34 are not mounted diametrically opposite each other in the present case. Of course, this would also be an option. The predetermined breaking point bridges 34 are expediently distributed uniformly over the circumference, wherein the number may be even or odd. In the present case, an odd number is assumed, which is why no diametrically opposite predetermined breaking point bridge 34 is visible. The cutting element 3 has any number of teeth 35, which may be arranged uniformly or unevenly distributed over the circumference. The teeth 35 have a sharp tip 36, which serves to push through the package, and then corresponding cutting edges 37, which pierced the Able to cut packaging film. The teeth 35 rest on a rim, which is offset from the cylindrical pipe section 30 by at least half the wall thickness of the cylindrical pipe section 30 inwardly. This creates an outwardly projecting circumferential shoulder 38. This circumferential shoulder 38 forms the lower edge 33 of the cylindrical pipe section 33 of the cutting element 3 in the present case.

Thanks to this projection 38, the predetermined breaking point bridges 34 can be kept very short and small. The distance between the lower edge 33 of the cutting element 3 and the upper edge 25 of the cylindrical pipe section 20 of the spout 2 can be reduced so practically to the size of the thread height of the internal thread 23. Thanks to the internally threaded ring with the teeth 35 remains a sufficient tool wall between the teeth 35 and the inner surface of the cylindrical pipe section 20 of the spout 2, so that the injection mold takes no damage during demolding and can also be provided with sufficient cooling.

Finally, the cutting element 3 has at least one driver 39 which extends from the upper edge 32 of the cutting element in the axial direction downwards and is directed at least approximately to the center. This driver 39, which has essentially the shape of a longitudinal rib, is usefully arranged so that it extends from the upper edge 32 to the tip 36 of a tooth 35. Since it only needs such a driver, the drivers are not visible on all teeth.

With respect to the description of the third main component of the opening device 1, namely the cap 4, is on the FIG. 3 directed. In this view, the opening device 1 is shown in the fully assembled state before Erstöffnung. The cap 4 has a top surface 40, which is surrounded by a peripheral peripheral jacket wall 41. The jacket wall 41 has on the outside grooves 42, which increase the grip of the cap 4. On the shell inside a thread 43 is attached, which is designed as a fine thread. This fine thread 43 meshes with the already mentioned external thread 22 of the spout 2. On the underside of the top surface 40, a circumferential annular bead 44 is present, which is mounted in the present example on the outside of an annular wall 45. The annular wall 45 runs concentrically with the jacket wall 41. Furthermore, at least one driver 46 is integrally formed on the underside of the top surface 40 of the cap 4, which is directed vertically from the top surface projecting axially downwards and also extends a short distance towards the center. This driver 46 is integral with an inner annular wall 47 as an extension thereof designed. The driver 46 cooperates with the already mentioned driver 39 on the cutting element 3.

Furthermore, a guarantee strip 48 is integrally formed on the cap 4, which is connected via predetermined breaking point bridges 49 with the lower edge of the jacket wall 41. The previously mentioned separating means 24 engage between two adjacent predetermined breaking point bridges 49 between the lower edge of the casing wall and the upper edge of the guarantee strip through the corresponding gap.

That in the FIG. 1 shown semi-finished product can be mounted easily. The predetermined breaking point bridges 34 are in the region of the connecting tip, virtually without a remaining remainder on the casing wall inner surface of the cylindrical pipe section 20 to tear off, the main part of the predetermined breaking point bridges 34 in the region of the lower edge 33 of the cutting element 3 remains. This hardly disturb the same, since the external thread 31 on the cylindrical pipe section 30 and the internal thread 23 on the cylindrical pipe section 20 of the spout 2 provides no multiple use and a single scratching of the thread is completely unproblematic in the single use. The thread itself does not need to achieve any tightness. On the other hand, as already mentioned, the inner surface of the cylindrical tube section 20 remains virtually completely unhurt, so that one during the later use in this area immersed annular wall 45 with a sealing bead 44 can rest here absolutely tight.

With respect to the inventive mounting method is on the FIG. 4 directed. The assembly process shown here, which shows only the assembly of the semi-finished product is very schematic and can of course be subject to various expert additions or changes. The supply of semi-finished products is designated 50. The semi-finished products can pass directly from the injection molding machines via conveyor belts to the assembly station, which is designated as 500 in total. Of course, the semi-finished products can also be supplied from an intermediate storage of the assembly station 500.

The assembly station 500 comprises a first conveying surface 51, which may be designed as a conveyor belt or, as shown here, as a vibrating surface. The semi-finished products 5 are disordered as bulk material on the conveying surface 51 and are separated by the shaking, so that even adjacent semi-finished products 5 with its flange 21 of the spout 2 not overlapping on each other in the pressing region 56 arrive. Normally, the semi-finished products will come to rest either on their flange 21 or on the upper edge 32 of the cutting element 3 on the conveying surface 51. Occasionally, it may happen that the semi-finished products as indicated by 5 'in a tilted position on the conveying surface 51, in which case a transverse spar 54 is provided above the conveying surface 51, which is arranged so far above the conveying surface 51, that such inclined lying semi-finished product 5' with its flange at the traverse Holm 54 comes to concern, which comes to the semi-finished product 5 'to act a torque, so that the semi-finished product performs a tilting movement and comes to rest on the flange 21. The semifinished products enter the actual pressing region 56 through an inlet gap 57. The pressing region 56 is formed by a lower support conveyor belt 58 and an upper conveyor belt, which acts as a running pressing surface. The pressing surface 52 and the lower support conveyor belt 58, which is part and continuation of the conveying surface 51, converge so far in the pressing region 56 that they are spaced from one another at least the height of the semifinished product from the flange underside 21 to the upper edge 32 of the cutting element 3 , while at the end of the pressing region 56 there is a distance between the conveying surface in this region and the pressing surface which corresponds to the height of the pouring spout 2. The pressing surface 52 or the actual band of the conveyor belt, which forms the pressing surface 52, can be provided with a rubber-elastic viewing, so that on the one hand certain tolerances are lifted, and on the other hand to press the cutting element 3 with a low insertion depth into the spout 2. In this case, the upper edge 32 of the cutting element 3 comes to lie slightly below the upper edge 25 of the spout 2 in this case. Preferably, this difference carries a few tenths of a millimeter. Only if these are semi-finished products for relatively large opening devices, this distance can also be greater. In order to avoid evasion of the band of the pressing surface 52, a counterpressure element 53 can be mounted on the leading side of the conveyor belt on the rear side thereof.

It is obvious to the person skilled in the art that, instead of a vibrating surface, the conveying surface 51 can likewise be designed as a conveyor belt. In this case, therefore, the lower conveyor belt, which is present in the pressing region 56, can easily be designed to extend over the entire length of the assembly station 500. Also in this case, the surface does not need to be bent as shown here in the drawing. The advantage of the solution outlined here is that it is possible to intervene manually if there is possibly a jam in the region of the transverse spar 54. About the route 60 now the two parts that had formed the semi-finished, promoted away in the mounted state. The mounting of the cap on the already pre-assembled spout and cutting elements takes place in a next step, which is no longer the subject of the invention.

LIST OF REFERENCE NUMBERS

1

opening device

2

pouring spout

3

cutting element

4

cap

5

semi-finished product

20

cylindrical pipe section

21

terminal flange

22

External thread as a fine thread

23

Internal thread with trapezoidal cross-section

24

Release agent for separating the predetermined breaking point bridges

25

upper edge of the spout

30

cylindrical pipe section

31

external thread

32

upper edge of the cutting element

33

lower edge of the cutting element

34

Weakened bridges

35

teeth

36

top

37

cutting edges

38

circumferential heel

39

takeaway

40

cover surface

41

shell wall

42

grooves

43

inner thread

44

sealing bead

45

ring wall

46

takeaway

47

inner ring wall

48

guarantee strip

49

Weakened bridges

50

Feeder (directly or indirectly from spraying machine or intermediate storage)

500

assembly station

51

Conveying surface - conveyor belt or vibrating surface

52

Pressing surface - conveyor belt

53

Against pressing element

54

crossing spar

55

leading conveyor belt

56

Press area

57

inlet gap

58

lower support conveyor belt

60

captivity

Claims (6)

1. A closable opening device (1) for sealed packaging which contains a flowable medium, the device comprising a pouring nozzle (2) with a cylindrical tube portion (20) and a flange (21), which is provided with an internal thread (23) and an external thread (22), as well as a cylindrical cutting element (3) which is provided with an upper edge (32) defining a planar surface, whilst the lower edge (33) is provided with one or more teeth (35), and the inner peripheral surface thereof is provided with drive elements (39) acting in the radial direction, which cooperate with drive elements (46) in a screw cap (4), the pouring nozzle (2) with the flange (21) and the cylindrical cutting element (3) being produced as a one-piece semi-finished product (5), connected together via predetermined breaking point bridges (34), the cylindrical cutting element (3) of the semi-finished product (5) being located with its lower edge, on which the teeth are integrally formed, in the region of the upper edge (25) of the pouring nozzle (2), characterised in that on the lower edge (33) of the cylindrical tube portion (30) of the cutting element (3) above the teeth (35) a peripheral projection (38) which protrudes outwardly is present, and the external thread (31) is mounted above the projection and in that in the region of the projection (38) a plurality of predetermined breaking point bridges (34) are present which are oriented with a pointed end outwardly, and which in the region of the upper edge (25) of the pouring nozzle (2) are connected thereto in the unmounted position, the upper planar edge of the cutting element further protruding over the upper edge of the pouring nozzle in the unmounted state of the semi-finished product, whilst in the mounted state the cutting element (3) with its cylindrical tube portion (30) and the teeth (35) is entirely located in the cylindrical tube portion (20) of the pouring nozzle (2), and in that the predetermined breaking point bridges with the pointed ends are arranged to be oriented radially outwardly, and thus may be at least approximately broken off without a residue remaining on the peripheral internal surface of the cylindrical tube portion (20).
2. The opening device according to Claim 1, characterised in that the predetermined breaking point bridges (34) comprise a lower or upper edge which is oriented towards the pouring nozzle (2) and is aligned at least approximately with the upper edge (25) of the pouring nozzle.
3. The opening device according to Claim 1, characterised in that the screw cap (4) comprises a peripheral tamper-evident strip (48) which is integrally formed on the peripheral wall (41) thereof, and which in the mounted state before the initial opening of the opening device is retained relative to the flange (21) so that an annular sealing bead (44) which is integrally formed on the inner face of the top surface of the cap (4) is located above the upper edges (32, 25) of the cutting element (3) and of the pouring nozzle (2).
4. A method for mounting the closable opening device according to Claim 1, characterised in that all semi-finished products (5) are brought to bear on a supply surface (51) with the lower face of the flange or with the upper edge (32) of the cylindrical cutting element (3) defining a planar surface, whereupon a second pressing surface (52) which approaches the supply surface (51) comes to bear on the semi-finished product (5), and the two surfaces (51, 52) approaching one another to such an extent that the two parts (2, 3) of the semi-finished product (5) are pushed into one another, destroying the existing connections and namely to such an extent that the upper edge (32) of the cylindrical cutting element (3) is located at least approximately aligned in a plane with the upper edge (25) of the pouring nozzle (2).
5. The method according to Claim 4, characterised in that the semi-finished products (5) are located unaligned on the lower supply surface (51) and are passed below a crossmember (54) traversing the supply surface, the semi-finished products (5), which do not bear in a planar manner on the upper edge (32) of the cutting element (3) or on the flange (21) of the pouring nozzle (2), being tilted.
6. The method according to Claim 4, characterised in that the opening devices (1) are mounted on the supply surface (51) so that said opening devices bear thereon with their flanges (21) whilst the pressing surface (52) is designed as a belt with a rubber elastic support, which pushes the cutting elements (3) sufficiently far into the pouring nozzle (2) that the upper edge (32) of the cutting elements (3) is pushed in several tenths of a millimetre below the upper edge (25) of the pouring nozzle (2).

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