CA2138321A1

CA2138321A1 - Device for opening a foodstuff package

Info

Publication number: CA2138321A1
Application number: CA002138321A
Authority: CA
Inventors: Leif Jonsson; Tommy Nilsson
Original assignee: Individual
Current assignee: Tetra Laval Holdings and Finance SA
Priority date: 1993-12-22
Filing date: 1994-12-16
Publication date: 1995-06-23
Also published as: EP0663344A1; JPH07215354A; DE4343816A1; TW271427B; CN1109015A; BR9405157A; KR950017671A

Abstract

An opening device for a liquid package which is attached to the top (1) of the package is provided with a screw cap (41) and a cylinder jacket shaped supporting ring (7).

In order to improve such a device to the effect that it is easier to manufacture, simpler to open and in no respect affects the quality of sealing of the package,it is provided according to the invention that the cylinder jacket shaped supporting ring (4) is attached to the top (1) of the package (2) by means of a fixing flange (5) externally surrounding an opening disc, is provided on its inner surface (12) with a raised thread (13) and surrounds the external thread (16) of the screw cap (41 ) formed from plastics material and that a cutter (18)is integrally moulded onto the free edge (17) of the screw cap (41), which is provided with a front cutting edge (19) which passes at an angle through the free edge (17).

Description

~13832~

.

Device for opening a foodstuff package The invention relates to a device for opening a foodstuff package which is aKached to the top of the package, having a screw cap and a cylinder jacket shaped supporting ring.

15 Devices for opening packages are known which are composed of a supporting ring and a screw cap screwed thereupon, wherein the supporting ring is attached to a hole previously made in the top of the package. The hole in the top by its very nature causes sealing problems which have to be made good by appropriate seals between the supporting ring and screw cap. It is 20 unavoidable that the opening device has to be provided with reliable sealing fittings, whereby more expensive manufacturing and possibly also more difficult opening have to be taken into account.

In-house, the use of clamp caps with internal cutting knives has already been 25 provided for. For this, however, one particular embodiment of the top had to be depended upon, namely to provide surfaces for the knives by means of said embodiment, which could be cut through. Apart from the fact that the cuKing knives in the detachable cap had to be arranged in a suitably conceaied manner so that the handler and end user would not risk being cut 30 by touching the package, the particular embodiment of the top of the package was limited to plastics packages as with these the cylinder jacket shaped ~13~32i .

raised parts could be manufactured by deep-drawing.

The object of the invention is to provide a device of the type described in the introduction, which is simple to manufacture and easy to open and does not 5 affect the quality of sealing of the package in any respect.

This object is solved according to the invention in that the cylinder jacket shaped supporting ring is attached to the top of the package by means of a fixing flange externally surrounding an opening disc, is provided internally with 10 a raised thread, and surrounds the external thread of the screw cap formed from plastics material, and in that a cutter is formed integrally on the free edge -of the screw cap which is provided with a front cutting edge which p~ssés through the free edge at an angle. Using the new device it is possible to keep the package completely closed before initiat opening, that is to say after filling, 15 during transport and during storage, so that the quality of sealing of the package is not affected in any respect re~ardless of the configuration of the opening device. The main advantage of the new device is also in its diversity of application. Not only the majority of plastics packages but also packages made from materials bonded with paper can be provided with and opened by 20 this new opening device. It is simply necessary for the opening device to be securely attached to the top at the point where later the pouring aperture will be wanted. Packaging materials for foodstuffs normally have a plastics surface, however, be it that the whole top is composed of plastics material or that the bonded material has a thin plastics coating. However, even with non-25 coated cardboard materials the cylinder j2cket shaped supporting ring of thenew opening device could be attached by gluing. The fixing flange of the supporting ring, which surrounds the opening disc, is for this purpose. The opening disc is that part which is at least partially cut out of the top which is to be opened, thus clearing the pouring aperture. For reasons of clarity, in the30 description the part of the top which is at least partially removed by the cutter of the new opening device to create the pouring aperture is described as the 21 3~32~

opening disc.

The supportins ring of the present invention does not include an external thread, as in the prior art, onto which a screw cap with an internal thread is 5 screwed, rather it includes a raised thread on its inner surface. This can be a single or a multiple thread with a single or multiple spirally formed ridge, as appropriate. With the preferred embodiments described in the following it is sufficient to form on the inner surface of the supporting ring a raised thread which extends over approximately 360. Pref~rably the supporting ring is 10 made of plastics material. It can however be manufactured from other materials as long as these can be glued or attached in some other manner to the top. In the configuration according to the invention, the raised thread of the supporting ring internally surrounds the external thread of the screw cap, wherein the screw cap is preferably formed from pl~-stics material. Roughly 15 speaking, without any particularly critical sealing means, the opening deviceis composed only of the outer supporting ring inside which the screw cap is held. The screw cap has a free edge oriented downwards towards the still closed top, on which, particularly advantageously, the cutter mentioned is integrally formed. The manufacture of such a cutter is technically simple and 20 extremely economical. The packaging manufacturer can manufacture such screw caps in large numbers at low cost and in a short time. The cutter is not engaged with the top after manufacturing, during transport and also during storage of the package concerned in this case, that is before initial opening of the package by the end user. The screw cap is screwed into the supporting 25 ring only far enough for the screw cap to be held and the cutter remains above the undamaged top. In this case it is advantageous when according to the previous description the cutter has a front cutting edge which passes through the free edge at an angle. This front cutting edge can be straight or curved and has this inclination towards the free edge of the screw cap so that 30 a cutting action similar to that of a knife blade can be easily perforrned by the end user. If the user indeed wishes to open the package he only has to screw the screw cap further into the supporting ring in a direction indicated for example by an arrow or another sign and the front cutting edge of the cutter will engage with the top. This engagement occurs at a point on the periphery of the previously described opening disc in the top. By rotating the screw cap 5 the front cutting edge, which is diagonally arranged with respect to the central longitudinal axis of the screw cap and the supporting ring, moves at least some way along the periphery of said opening disc and separates it from the top in the area inside the supporting ring. In this way the top of the package is opened and the end user can empty out the contents.
In a further advantageous embodiment of the invention the leads of the raised thread on the supporting ring and the axial height of the cutter from the free edge in the direction of the package are coordinated such that the front cutting-edge is moved completely through the plane of the top when the screw cap 15 is rotated by approximately 270. The front cutting edge has a certain lengthwhich is generally greater than the axial height mentioned. The end of the front cutting edge which is located furthest out and below understandably enters the top first, and as a result of the further rotation of the screw cap penetrates the top so that the parts of the front cutting edge subsequently 20 following engage in a cutting action until during the further rotation of thescrew cap the front cutting edge is pushed completely through the plane of the top. The cutting action then ceases, even if the screw cap is rotated further as the front cutting edge is then wholly located inside the package, that is to say below the top, and perforrns no further cutting function. The same 25 also applies when the screw cap is rotated by approximately 270 and more, but not much more than 350 so that the opening disc remains hanging on and does not fall into the contents.

The axial height of the cutter from the free edge in the direction of the 30 package, that is from the top thereof, lies in the direction of the central axis, that is it is measured in this direction, which is why it is called "axial" height.

213~321 If the screw cap is viewed in longitudinal sechon, or in a lateral view perpendicular to the central axis of the screw cap, wherein the top then appears preferably as a straight line as it is viewed from along the surface of the top, the free edge of the screw cap then also appears as a line. If the front 5 end of the front cutting edge facing the top is not yet engaged with the top the free end of the screw cap is at a distance which seen from the direction perpendicular to the central axis is the height mentioned of the cutter. It can also be said that the front cutting edge of the cutter has a component in the direction of the central axis and from the point where the front cutting edge 10 intersects the free edge to the surface of the top this axial component of the front cutting edge is exactly the size of the axial height mentioned. - ~ -It is preferable if the lead of the raised thread or the lead of the external-thread of the screw cap is larger than the axial height of the cutter. In this 15 case the cutter needs an angle of rotation of less than 360 from the point of puncturing the top at the beginning of the rotation to the moment when the inner end of the front cutting edge is forced right through the top, which is called the end point of the partial circular cut. The advantageous result of this measure is that the opening disc cut out of or cut into the top is not 20 completely cut out from the top and thus cannot fall into the inside of the package into the contents; instead an uncut connection remains between the opening disc and the top which surrounds it, like a bridge which holds the opening disc securely in a reliable manner.

25 As the cutter only extends over a fraction of the periphery or free edge of the screw cap according to the invention it is ensured that the remaining predominant part of the periphery of the free edge of the screw cap carries the thread. The result of this is the advantage that when the screw cap is rotated further, while the front cutting edge is not engaged with the top, being30 inside the package, the adjacent thread now grasps the opening disc and folds down like a flap so that the area of the opening disc is clear and thus 2~383~1 _ 6 the pouring aperture is completely opened.

By means of the opening device according to the invention before the cutter cuts, there is a perfectly closed top and therewith a sealed package and by 5 rotating the screw cap the pouring aperture is made in an advantageous manner just because the opening disc is folded down when it has been cut sumciently, for example over an angle of rotation of approximately 270 and does not get in the way when the contents are emptied.
.

10 It is furthermore advantageous according to the invention when the supportingring is divided by a predetermined breakage line into a lower seating part with the fixing flange and a spacing ring which is provided with a supporting flange holding the rotating part of the screw cap. By means of these measures it is-possible to screw in and retain the screw cap in a defined position prior to 15 initial opening of the foodstuff package, that is to say in a position in which the cutter does not yet engage with the top, in a simple way. This is achieved in that the rotating part of the screw cap is held by the supporting flange and cannot be rotated any further towards the top. The end user has first to remove the spacing ring with the supporting flange mentioned by breaking the 20 predetermined breakage line, and can then screw the screw cap further into the remaining seating part with the result that the cuKer penetrates the top.

Use is further simplified by the measure according to the invention in that the supporting ring is composed of plastics material which can be welded to the 25 top, and on the spacing ring a flap is formed for removing the spacing ring from the seating part. Plastics material is the easiest to mould, and even complicated configurations can be manufactured inexpensively by injection moulding. The moulding on of a grip flap or tear flap presents no problems.
Predetermined breakage lines can also be introduced easily and reliably 30 between the seating part and spacing ring, and the aKachment to a top which is provided at least with a plastics material surface is known technology. In 21~832:~

this way the opening device according to the invention can be simply, easily and reliably placed on the package so that after tearing off the spacing ring with the aid of the flap opening of the package is made possible.

5 In a preferred first embodiment of the invention ~e cutter is provided with a point which projects downwards, over the free edge towards the p~rk~ge. The previously described axial height is then the ~Istance measured in the direction of the central axis of the point of the cutter from the free edge of the screw cap. It is advantageous to injection mould such a cutter onto the screw 10 cap using the same plastics material as for the rotating part of the screw cap.
It is then integral.

It is advantageous in this case when the screw cap has a rotating part which is radially larger, and placed thereon a radially smalle!, preferably hollow 15 cylindrical threaded projection with an external thread which is trapezoidal in cross-section, and when the free edge of the screw cap is sharpened on the outside of at least a part of its periphery in such a way that the sharpened external contour lies in the surface forming base of the external thread.
Plastics material and paper as well as coated paper and other bonded 20 materials can be cut with such a cutter in the manner described herein and an opening device thereby created. The hollow cy~indrical threaded projection can be manufactured by injection moulding as far as its final configuration. It is also possible, however, either to configure the external thread in a trapezoidal forrn by turning the rotationally sy-,...,~t-ical tooling parts or to 25 sharpen the free edge of the hollow cylindric~ ~readed projection in the manner described. In the cutter embodiment usin~ plastics material the cutter itself can be manufactured by such rotationa~ w~rking in an advantageous manner.

30 Whereas, for example, the cutter is provided wi~ the previously mentioned point for bonded or paper materials and In ar; advantageous manner is 2~3832~

moulded by injection moulding, the cutter can be manufactured for use with plastics materials so that according to the invention the front cutting edge of the cutter is arranged in the external raised part of the external thread of thescrew cap. The front cutting edge is preferably straight. If a conical surface, for example that of a rotary tool, cuts the hollow cylindricai threaded projection made of plastics material in such a way that the cutting line p~sses through the projecting part of the external thread and intersects therewith, then a straight front cutting edge of the cutter is formed in the external raised part of the external thread of the screw cap without further injection measures being necessary for forming the cutter.

The man skilled in the art will recognise that by means of the embodiments-described an opening device for a package is provided which does not in an~
respect affect the seal of the package until initial opening, but at the same time allows easy opening and even re-closure.

Further advantages, features and possibilities for application of the present invention are derived from the following description of preferred embodiments with reference to~he attached drawings, which show in Figure 1 a partly fragmentary lateral view and partial longitudinal section of a first embodiment of an opening device before use for opening, Figure 2 a fragmentary partial section through the screw cap, Figure 3 a plan view of the screw cap shown in Figure 2, from right to left, Figure 4 a view like that of Figure t wherein after removal of the spacing ring the screw cap is screwed down far enough in the direction of the inside of the package so that not only is the cut made along a periphery over approximately 270 in the opening disc, but this is g also folded down in a flap-like manner, Figure 5 a plan view of the cut, but not folded down or bent up top, together with the seating part, Figure 6 a similar view to that of Figure 1, however showing a second, other embodiment, and Figure 7 a longitudinal sectional view through the screw cap of the second embodiment shown in Figure 6 with a representation analogous to that in Figure 2.

On the top 1, assumed to be flat, of a liquid pArk~e 2 shown only in a schematic and fragmentary manner, the plastic supporting ring 4, circularly symmetrical with respect to the central axis 3, is welded by means of the fixing flange 5 to 6. The supporting ring 4 is composed of the seating part 7 and the spacing ring 8 which are both separated from one another by the predetermined breakage line 9 running parallel to the top 1. The spacing ring 8 is provided on its upper part with the radially outwardly extending supportingflange 10 and a tear flap 11 moulded onto the right of the ring 8.

The supporting ring 4, and in particular the seating part 7 has on its circular inner surface 12 a raised thread 13 which extends over a good 360.

25 The screw cap 41 is composed of a radially larger rotating part 14 and a threaded projection 15 radially smaller with respect thereto. which is configured as a hollow cylinder and has a noticeably smaller radius than the rotating part 14. The external thread 16 of the threaded projection 15, and thus also of the screw cap 41, fits during rotary engagement into the annular 30 ring 13 and the external periphery of the rotating part 14 fits into the supporting flange 10 and comes to rest on this flat, horizontal ring.

On the free edge t7 of the screw cap 41 a cuKer 18 is located which has a straightfront cuKing edge 19, the component of which, in the direction of the central axis 3 from the free edge 17 to the lowest end 20 facing the top 1 is called the axial height H of the cuKer 18.

In the first embodiment according to Figures 1 to 5, the front end 20 of the front cuKing edge 19 is configured in the shape of a point 20, and this cuKer 18 serves ~o sever material containing paper. In the embodiment according to Figures 6 and 7 the front end 20 of the cutter 18 is configured flaKer and 10 serves to sever a top 1 made of plastics material.

The severing is done at the outer periphery of the opening disc 21 shown in Figure 5 which is circular and is cut along the cuKing line 22 over an angle of 270. In Figure 5 the cut but not bent up or folded away opening disc 21 is 15 shown with the seating part 7 surrounding the opening disc 21, with the fixing flange 5. The innermost surface of the raised thread 13 is shown as a circle 23 and on this circle 23 lies the cuKer which is not visible in hgure 5 as the screw cap 41 is not screwed in in the representation in Figure 5.

20 Figures 1 and 6 show the opening device before the initial opening, wherein in this state the front end 20 or point of the cuKer 18 has not yet engaged withthe top 1. rhis is achieved by the axial length of the hollow cylindrical threaded projection 15 being set at the height of the supporting ring 4. Strong pl~ in af the front end 20 of the cuKer 18 is not possible because the 25 radially larger rotating part 14 is held in the supporting flange 10 of the supporting ring 4.

For opening, the end user grips the flap 11 and tears the spacing ring 8 along the circular predetermined breakage line 9. In this way the screw cap 41 can 30 be further rotated clockwise so that the threaded projection 1~ with the cutter 18 moves downwards in the direction of the central axis 3 towards the top t.

21~32~

With this the point or front end 20 of the cutter 1:8 pe,~ ates the top, ~or exarnple at the point designated 24 shown in hgure 5. When the ærew cap 41 is further rotated in the direction of the curved arrow 25 (clockwise) the front cutting edge 19 runs along the circular periphery of the apening disc 21 along the three-quarter circle 22 according to Figure 5 as far.as the point designated 26. Along this circular path between the points 24 and 26 the front cutting edge 19 penetrates deeper and deeper into the top 1, so ttat the innermost, furthest back end 27 of the front cutting edge 19 stops cutting at the point 26. If even after this the user rotates the screw cap 41 a bit further10 in the direction of the arrow 25, the front cutting edge does not perform anyfurther cutting as it has dipped inside the package, below the plane o~the top 1. Rather, the adjacent thread according to the representation in hgure 4;
ensures that the opening disc 21 which is shown only in a fragmentary~
manner in Figure 4, is bent and at least partially folded away into an acute 15 angle. If thereafter, that is to say after making the pouring aperture, the screw cap 41 were to be unscrewed, the pouring aperture would be open and the user could empty out the contents.

~ ~, ... . . . . ... . ...

Claims

1. Device for opening a foodstuff package which is attached to the top (1) of the package, with a screw cap (41) and a cylinder jacket shaped supporting ring (4), characterised in that the cylinder jacket shaped supporting ring (4) is attached to the top (1) of the package by means of a fixing flange (5) externally surrounding an opening disc (21), is provided on its inner surface (12) with a raised thread (13) and surrounds the external thread (16) of the screw cap (41) moulded from plastics material, and that a cutter (18) is integrally moulded onto the free edge (17) of the screw cap (41), which is provided with a front cutting edge (19) passing at an angle through the free edge (17).

2. Device according to claim 1, characterised in that the lead of the raised thread (13) on the supporting ring (4) and the axial height (H) of the cutter (18) from the free edge (17) in the direction of the package are coordinated with one another so that the front cutting edge (19) is moved completely through the plane of the top (1) by rotation of the screw cap (41) by approximately 270°.

3. Device according to claim 1 or 2, characterised in that the supporting ring (4) is divided by a predetermined breakage line (9) parallel to the fixing flange (5) into a lower seating part (7) with the fixing flange (5) and a spacing ring (8) which is provided with a supporting flange (10) holding the rotating part (14) of the screw cap (41).

4. Device according to one of claims 1 to 3, characterised in that the supporting ring (4) is composed of plastics material which can be welded to the top (1) and a flap (11) is moulded onto the spacing ring (8) for removing the spacing ring (8) from the seating part (7).

Device according to one of claims 1 to 4, characterised in that the cutter (18) is provided with a point (20) downwardly projecting over the free edge (17) and directed towards the package.

Device according to one of claims 1 to 5, characterised in that screw cap (41) is provided with a radially larger part (14) and placed thereon a radially smaller, preferably hollow cylindrical threaded projection (15) with an external thread (16) with a trapezoidal cross-section and that the free edge (17) of the screw cap (41) is sharpened on at least a part of its periphery so that the sharpened external contour (19) lies in the surface forming the base of the external thread (16).

Device according to one of claims 1 to 4, and 6, characterised in that the front cutting edge (19) of the cutter (18) is arranged in the external raised part of the external thread (16) of the screw cap (41).

Device according to claim 1, characterised in that the lead of the raised thread (13) on the supporting ring (4) and the axial height (H) of the cutter (18) from the free edge (17) in the direction of the package are coordinated with one another so that the front cutting edge (19) is moved completely through the plane of the top (1) by rotation of the screw cap (41) by approximately 270° to 350°.