WO2002098760A1

WO2002098760A1 - Apparatus for ejecting an article from a blister pack

Info

Publication number: WO2002098760A1
Application number: PCT/AU2002/000744
Authority: WO
Inventors: John Ernest Oretti; Gareth William Lewis
Original assignee: Blast Packaging Pty Ltd
Priority date: 2001-06-07
Filing date: 2002-06-07
Publication date: 2002-12-12
Also published as: AUPR551901A0

Abstract

Apparatus for ejecting an article or tablet (7) having an ejecting member (40) and a blister pack (3) mounted for movement relative to one another, the blister pack having a blister layer with a blister (3) projecting from the blister layer to define a recess for receiving an article, and a lidding layer attached to said blister layer, the lidding layer having a seal portion (9) overlying said recess, the apparatus being configured so that the article (7) is ejected by the ejecting members (40a, 40b) applying force through the blister to the article in such a manner that the article (7) applies force unevenly to the seal portion (9) to thereby rupture the seal portion. The blister (3) can also have an offset projection (15) into the recess to bear against the tablet to thereby cause the tablet to tilt and apply force unevenly to the seal portion.

Description

APPARATUS FOR EJECTING AN ARTICLE FROM A BLISTER PACK

Field of the Invention

The present invention relates to improvements in packaging. More specifically, the present invention relates to techniques for reducing the force required to eject an article from a blister pack.

Background to the Invention Blister packs are commonly used to store tablets or capsules. A blister pack consists of a blister layer and a lidding layer. The blister layer has one or more blisters projecting from the blister layer which each define a recess in which an article such as a tablet may be received. The lidding layer is laminated to the blister layer to seal the tablets within the blisters. The lidding layer has seal portions corresponding to respective ones of the blisters of the blister layer. In order to eject the tablet from the blister, force is applied to the blister surface which is then transferred by means of the tablet to the interior of the seal portion of the lidding layer to thereby cause the seal portion to rupture so that the tablet can be ejected from the blister pack.

If the tablet applies force evenly to the seal portion, it may cause the seal portion to flex rather than rupture. This is a particular problem with small and/or circular tablets as well as spherical or part spherical tablets and/or capsules.

Further, persons with reduced control of their fingers, such as arthritis sufferers can find it difficult to burst the blister pack. Therefore, it would be desirable to provide an improved blister pack which is easier to open. Further to the foregoing, in US patent 6,170,654 which is co-owned by the present applicants, there is disclosed a closure cap for retaining an additive which can be dispensed into an associated bottle upon opening of the closure cap. In the preferred embodiment, the additive is a tablet retained within a blister pack. As the cap is opened, a central post presses on the blister pack and force is transferred through a tablet retained within the blister pack to the lidding layer in order to rupture the lidding layer of the blister pack and to release the tablet into an associated container. It has been found that other constructional limitations reduce the extent to which the blister pack can travel relative to the post. These constructional limitations have the potential to lead to more than a desirable amount of force being required to be applied in order to rupture the lidding layer. Accordingly, it would be advantageous to provide apparatus for ejecting an article such as a tablet which is suitable for use with the closure cap described in the above US patent, to thereby reduce the force required to rupture the lidding layer.

Summary of the Invention

The present invention provides apparatus for ejecting an article, having an ejecting member and a blister pack mounted for movement relative to one another, the blister pack having a blister layer with a blister projecting from the blister layer to define a recess for receiving an article, and a lidding layer attached to said blister layer, the lidding layer having a seal portion overlying said recess, wherein said article is ejected by said ejecting member and said blister pack being moved relative to one another so that said ejecting member applies force through said blister to said article in such a manner that said article applies force unevenly to said seal portion to thereby rupture said seal portion. Preferably said ejecting member is fixed and said blister pack is movable.

Alternatively said ejecting member is movable and said blister pack is fixed.

Preferably said ejecting member is shaped so as to apply force unevenly to said blister to thereby apply force to said article.

Preferably said ejecting member has a leading portion for applying force unevenly and a following portion for engaging the blister to ensure ejection of the article.

Preferably said apparatus includes stiffening means for reducing the ability of the blister pack to flex in the region surrounding said sealed portion.

Preferably said stiffening means is provided by a stiffening ring attached to said blister pack around said seal portion.

Preferably said stiffening ring has a projection projecting inwardly of the ring, whereby when force is applied to said seal portion by said article stress is concentrated in the region around said projection.

Preferably said apparatus is incorporated into a closure cap.

Accordingly, the invention provides a blister pack having: a blister layer with a blister projecting from the blister layer to define a recess for receiving an article; and a lidding layer attached to said blister layer, the lidding layer having a seal portion overlying said recess, wherein said blister is shaped so that when force is applied to said blister, said article applies force unevenly to said sealed portion to thereby cause said sealed portion to rupture.

Preferably, said blister is shaped so that said article applies force to a small region of said sealed portion.

Preferably said blister is shaped so as to have a force applying portion projecting inwardly into the recess towards the seal portion, the force applying portion being offset from a centre line of the blister.

Alternatively said blister is shaped to have a zone of weakness, whereby when said force is applied to said blister said blister collapses in the area of the zone of weakness to thereby cause said article to apply force unevenly to said seal portion.

Preferably said blister layer has a plurality of blisters, and said lidding layer has a corresponding plurality of seal portions.

The invention also provides a blister pack having: a blister layer with a blister projecting from the blister layer to define a recess for receiving an article; a lidding layer attached to said blister layer, the lidding layer having a seal portion overlying the recess; and stiffening means for stiffening the blister pack in the region surrounding said seal portion. Thus, the stiffening means reduces the propensity for the blister pack to flex without rupturing said seal portion.

Preferably said stiffening means is a stiffening layer attached to a side of said lidding layer opposite said blister layer, said stiffening layer having a cut-out portion corresponding to said sealed portion whereby said article may be ejected through said cut-out portion.

Preferably said stiffening layer has at least one projection projecting into the cut-out portion, whereby when force is applied to said seal portion by said article, stress is concentrated in the region of said projection.

Preferably said stiffening layer has a plurality of projections, said projections being formed so as to allow clearance for rejection of said article from said blister pack.

The invention also provides a blister pack having: a blister layer with a blister projecting from the blister layer to define a recess for receiving an article; a lidding layer attached to said blister layer, the lidding layer having a seal portion overlying said recess; and stress concentration means including a projection extending over said seal portion, whereby when force is applied to said seal portion by said article stress is concentrated in the region of said projection.

Preferably said stress concentration means includes a plurality of projections. Preferably said stress concentration means is provided by a projection carrying layer attached to a side of said lidding layer opposite said blister layer.

The invention also provides a closure cap having a body portion and a first portion movable relative to the body portion to open the cap, one of the body portion and the first portion carrying a blister pack and the other one of the body portion and the first portion carrying an ejecting member whereby movement of the first portion relative to the body portion ruptures said blister pack and ejects an article contained in said blister pack from the blister pack, the closure cap also including stiffening means located next to a lidding layer of said blister pack in order to reduce flexibility of said blister pack to thereby enhance rupturing of said blister pack.

The invention also provides a closure cap having a body portion and a first portion movable relative to the body portion to open the cap, one of the body portion and the first portion carrying a blister pack and the other one of the body portion and the first portion carrying an ejecting member whereby movement of the first portion relative to the body portion ruptures said blister pack and ejects an article contained in said blister pack from the blister pack, the closure cap also including stress concentrating means located next to a lidding layer of said blister pack in order to concentrate stress in an isolated region of said lidding layer to thereby enhance rupturing of said blister pack.

Brief Description of the Drawings Embodiments of the invention will now be described in relation to the accompanying drawings in which: Figure 1 shows a prior art tray of blister packs;

Figure 2 shows a tray of blister packs of a first embodiment of the present invention;

Figure 3 shows a tray of blister packs of a second embodiment of the present invention;

Figure 4 shows a prior art blister pack;

Figure 5 shows a blister pack of first preferred embodiment of the present invention being opened;

Figure 6 illustrates the opening of a blister pack of a second preferred embodiment of the invention;

Figure 7 illustrates a tray of blister packs according to a third preferred embodiment of the invention;

Figure 8 illustrates the opening of blister pack of the third preferred embodiment;

Figure 9 shows a closure cap incorporating apparatus for ejecting a tablet;

Figure 10 shows the tablet of Figure 9 being ejected; Figure 11 shows a support ring for use in the closure cap of Figure 9;

Figure 12 shows a variation on the apparatus of Figure 9 ; and

Figure 13 shows the apparatus of Figure 12 being opened.

Description of the Preferred Embodiment

Figure 1 shows a typical prior art tray of blister packs 3a, 3b. The tray 1 has a blister layer 2 which has a plurality of blisters 3a, 3b which project from the blister layer 2 in order to define recesses within which tablets 7a, 7b are received. A lidding layer 5 is attached to blister layer 2 by being laminated to the blister layer 2 and has seal portions 9a, 9b which over lie the recesses.

Typically the blister layer 2 is a laminate of a number of different materials. For example, the blister layer is typically a laminate of materials such as PVC, polyethylene and polyamides. The blister layer typically has a thickness in the order to 120μm to 400μm.

The lidding foil is typically formed of aluminium and a lacquer which can be printed upon.

Alternative blister packs are known where the blister layer is a laminate of aluminium and polyethylene and polyamide. However, these blisters are less preferred because their side walls must have a relatively substantial draft compared to plastic blister packs.

Figure 4 illustrates one of the problems with prior art blister packs. As force is applied to the tablet 7 blister 3 as indicated by arrow 20 the force is distributed evenly over the seal portion 9 which flexes rather than rupturing. For persons with reduced control of their fingers, such as sufferers of arthritis, it can be difficult to apply sufficient force in order to cause the seal portion to rupture.

Figure 2 shows one possible solution to this problem. In this first embodiment, stiffening means is provided to stiffen the blister pack in the region surrounding the seal portion 9. In the first embodiment illustrated in Figure 2, the stiffening means is provided by a stiffening layer 13 of similar construction to the blister layer 2. The stiffening layer 13 has cut-out portions which correspond to the seal portions 9a, 9b and is laminated to the opposite side of the lidding layer 5 to the blister layer.

Thus, as illustrated in Figure 5, when force is applied as indicated by arrow 22, the seal portion 9 of the blister pack 11 cannot flex to the same degree as shown in Figure 4 and is caused to rupture at point 17 as illustrated in Figure 5.

The performance of this blister pack 11 can be enhanced by adding stress concentration means in the form of one or more projections 12 which project into the cutout portion, whereby when force is applied to the sealed portion by the tablet 7a as illustrated in Figure 2, stress will be concentrated in the region of the projection 12 to thereby enhance rupturing of the seal portion 9a.

It will be apparent to those skilled in the art that the stress concentration means which is provided by the projection 12 can be provided as an alternative to the stiffening layer instead of being in addition to the stiffening layer. In this case, a projection carrying layer can be laminated or otherwise attached to the lidding layer.

Figure 3 illustrates an alternative blister pack 21 of a second preferred embodiment. In this embodiment, force applying portions are provided in the form of indents in the blisters 3a, 3b which project into the recess. It should be noted that these projections 15a,

15b are offset from the centre line of the blister 3a, 3b. Thus, as illustrated in Figure 6, when force is applied in the direction of arrow 24, the projection 15 will bear on the tablet 7 and cause it to tilt thereby applying force unevenly to the seal portion and also causing the article to apply force to a relatively small region of the seal portion to thereby cause the seal portion 9 to rupture at point 19. It will thus be appreciated that the projection has caused stress to be concentrated in the region of point 19 where the seal has ruptured.

Figures 7 and 8 illustrate an alternative technique for causing the tablets 7 to apply force unevenly to the seal portion 9 of the lidding layer 5. In this third embodiment, the blister pack includes a recessed step 32 which defines a zone of weakness in the blister 3. As illustrated by Figure 8 this causes the blister to collapse in the area of the zone of weakness to thereby cause the tablet to apply force unevenly to the seal portion 9; thus, causing the seal portion 9 to rupture in the vicinity of point 34.

Referring now to Figures 9 and 10 there is illustrated a push-pull type closure cap 60 incorporating apparatus for ejecting an article in the form of a tablet. The closure cap has an ejecting member 40 provided by a first leading member 40a and a second, shorter following member 40b for ejecting a tablet 7 stored in a prior art blister pack of the general type described above. Further constructional details of such closure caps are set out in US patent 6,170,654 the disclosure of which is incorporated herein by reference.

It will be noted that the blister pack and the ejection member are mounted for relative movement. In the illustrated embodiment, it is the blister pack which is movable and the ejecting member 40 which does not move.

Movement of the blister pack is achieved by moving first portion 42 of the closure cap 60 which carriers the blister pack relative to the body portion 45 which carries the ejecting member, to thereby move the closure cap 60 to an open position in which liquid can be dispensed from an associated container through aperture 48. In a closed position illustrated in Figure 9 the aperture 48 is closed by plug 43.

The closure cap 60 of the preferred embodiment incorporates several of the features of the blister packs discussed above. In particular, it is noted that the closure cap 60 has a stiffening means in the form of a support ring 46 which is fixed to the feet of a pair of legs 41 of the first portion 42. Thus, the support ring 46 reduces the propensity of the seal portion 9 to flex and hence improves rupturing of the seal portion. A plurality of teeth 47 are provided in order to concentrate force and further enhance rupturing of a seal portion 9.

It will be noted that the closure is configured so that force is applied unevenly to the seal portion 9 of the lidding layer 5. However, in contrast to the blister pack embodiments described above this is achieved by providing an ejecting member 40 which has an uneven profile so that it applies force unevenly to the blister 3 to thereby cause the tablet 7 to tilt and apply force unevenly to the lidding layer 5 to thereby enhance rupturing of the seal portion 9 of the lidding layer.

The ejecting member 40 has a leading member 40a and a following member 40b which is shorter than leading member 40a in order to apply this uneven force. The leading member 40a applies the initial force to cause the tablet 7 to tilt and to apply force unevenly. The following portion 40b then subsequently engages the blister 3 to aid in ejecting the tablet 7. That is, to prevent the tablet from staying within the recess defined by the blister once the seal portion 9 has been ruptured.

In Figures 9 and 10, the leading member 40a and the following member 40b are provided by two separate pillars. The ends of the pillar 40a is chamfered in order that force is applied at a point.

However, as illustrated in Figure 12, a similar effect can be achieved by providing a central tubular pillar 52 which is cut at an angle to thereby provide a leading portion 40a and a following portion 40b. Thus, as force is applied in the direction of arrow 50 as shown in Figure 13, the tablet 7 is caused to eject. The use of a tubular pillar 52 allows there to be a liquid path through the pillar.

Figure 11 illustrates the support ring 46 of Figures 9 and 10. It will be noted that there are a plurality of teeth 47 projecting into the cut out portion of the support ring 46. The presence of these teeth in Figure 9 allows stress to be concentrated along one side of the seal portion thereby increasing the stress concentration along the side and enhancing rupturing. Holes 48 are provided in the support ring 46 to enable the support ring 46 to be fixed to the member 41 of the first portion 42.

It will be apparent to persons skilled in the art that various modifications may be made to the foregoing embodiments without departing from the scope of the invention. In particular, it will be noted in relation to the embodiments illustrated in respect of Figures 9 and 10 that not all of the improvements to enhance the rupturing of the seal portion 9 of the blister pack need be employed in the closure cap. For example, some embodiments may just use the stiffening means or stress concentration means. Furthermore, it will be apparent that if a blister pack having a configuration such as that shown in Figure 3 or Figure 7 were used with the closure cap of Figures 9 and 10, the ejecting member could be symmetrical and not have a leading or following portion as the shape of the blister will cause force to be applied unevenly to the seal portion 9 of the blister pack.

Further, the closure cap may be configured so that the ejecting member moves and the blister pack is fixed. Thus, for example, a plunging motion could be used to release the tablet. Still further, it will be apparent that a zone of weakness can be created by strengthening an opposing portion of the blister, so that the non-strengthened portion becomes a zone of weakness which will collapse.

These and other modifications will be apparent to persons skilled in the art and should be understood as falling within the scope of the invention described herein.

Claims

CLAIMS :

1. Apparatus for ejecting an article, having an ejecting member and a blister pack mounted for movement relative to one another, the blister pack having a blister layer with a blister projecting from the blister layer to define a recess for receiving an article, and a lidding layer attached to said blister layer, the lidding layer having a seal portion overlying said recess, said apparatus being configured so that said article is ejected by said ejecting member and said blister pack being moved relative to one another so that said ejecting member applies force through said blister to said article in such a manner that said article applies force unevenly to said seal portion to thereby rupture said seal portion.

2. Apparatus as claimed in claim 1, wherein said ejecting member is fixed and said blister pack is movable.

3. Apparatus as claimed in claim 2, wherein said ejecting member is movable and said blister pack is fixed.

4. Apparatus as claimed in any one of claims 1 to 3, wherein said ejecting member is shaped so as to apply force unevenly to said blister so that said article applies force unevenly to said seal portion.

5. Apparatus as claimed in claim 4, wherein said ejecting member has a leading portion for applying force unevenly and a following portion for engaging the blister to ensure ejection of the article.

6. Apparatus as claimed in claim 4, wherein said ejecting member is formed as a first member and a second member, one member being longer than the other to thereby apply force unevenly to the blister.

7. Apparatus as claimed in claim 4, wherein said ejecting member is a cylindrical tube having a free end for applying force to said blister, said free end being cut-off at an angle in order to apply force unevenly to said blister.

8. Apparatus as claimed in any one of claims 1 to 3, wherein said blister is shaped so that when force is applied to said blister by said ejecting member, said article applies force unevenly to said sealed portion to thereby cause said sealed portion to rupture.

9. Apparatus as claimed in claim 8, wherein said blister is shaped so that said article applies force to a small region of said sealed portion.

10. Apparatus as claimed in claim 8 or claim 9, wherein said blister has a force applying portion projecting inwardly into the recess towards the seal portion, the force applying portion being offset from the centre of the blister.

11. Apparatus as claimed in claim 8 or claim 9, wherein said blister has a zone of weakness, whereby when said force is applied to said blister said blister collapses in the area of the zone of weakness to thereby cause said article to apply force unevenly to said seal portion.

12. Apparatus as claimed in any one of claims 1 to 11, wherein said apparatus includes stiffening means for reducing the ability of the blister pack to flex in the region surrounding said sealed portion.

13. Apparatus as claimed in claim 12, wherein said stiffening means is provided by a stiffening ring attached to said blister pack around said seal portion.

14. Apparatus as claimed in claim 12, wherein said stiffening ring has a projection projecting inwardly of the ring, whereby when force is applied to said seal portion by said article stress is concentrated in the region around said projection.

15. A closure cap including the apparatus of any one of claims 1 to 14.

16. A closure cap as claimed in claim 15, wherein said blister pack is carried by a first portion of the closure cap and said ejecting member being carried by a body portion of the closure cap, the first portion of the closure cap being moved relative to the body portion to open the closure cap and eject the article from the recess.

17. A blister pack having: a blister layer with a blister projecting from the blister layer to define a recess for receiving an article; and a lidding layer attached to said blister layer, the lidding layer having a seal portion overlying said recess, wherein said blister is shaped so that when force is applied to said blister, said article applies force unevenly to said sealed portion to thereby cause said sealed portion to rupture.

18. A blister pack as claimed in claim 17, wherein said blister is shaped so that said article applies force to a small region of said sealed portion.

19. A blister pack as claimed in claim 17 or claim 18, wherein said blister is shaped so as to have a force applying portion projecting inwardly into the recess towards the seal portion, the force applying portion being offset from a centre line of the blister.

20. A blister pack as claimed in claim 17 or claim 18, wherein said blister is shaped to have a zone of weakness, whereby when said force is applied to said blister said blister collapses in the area of the zone of weakness to thereby cause said article to apply force unevenly to said seal portion.

21. A blister pack as claimed in any one of claims 17 to 20, wherein said blister layer has a plurality of blisters, and said lidding layer has a corresponding plurality of seal portions.

22. A blister pack having: a blister layer with a blister projecting from the blister layer to define a recess for receiving an article; a lidding layer attached to said blister layer, the lidding layer having a seal portion overlying the recess; and stiffening means for stiffening the blister pack in the region surrounding said seal portion.

23. A blister pack as claimed in claim 22, wherein said stiffening means is a stiffening layer attached to a side of said lidding layer opposite said blister layer, said stiffening layer having a cut-out portion corresponding to said sealed portion whereby said article may be ejected through said cut-out portion.

24. A blister pack as claimed in claim 23, wherein said stiffening layer has at least one projection projecting into the cut-out portion, whereby when force is applied to said seal portion by said article, stress is concentrated in the region of said projection.

25. Apparatus as claimed in claim 24, wherein said stiffening layer has a plurality of projections, said projections being formed so as to allow clearance for ejection of said article from said blister pack.

26. A blister pack having: a blister layer with a blister projecting from the blister layer to define a recess for receiving an article; a lidding layer attached to said blister layer, the lidding layer having a seal portion overlying said recess; and stress concentration means including a projection extending over said seal portion, whereby when force is applied to said seal portion by said article stress is concentrated in the region of said projection.

27. A blister pack as claimed in claim 26, wherein said stress concentration means includes a plurality of projections .

28. A blister pack as claimed in claim 27, wherein said stress concentration means is provided by a projection carrying layer laminated to a side of said lidding layer opposite said blister layer.

29. A closure cap having a body portion and a first portion movable relative to the body portion to open the cap, one of the body portion and the first portion carrying a blister pack and the other one of the body portion and the first portion carrying an ejecting member whereby movement of the first portion relative to the body portion ruptures said blister pack and ejects an article contained in said blister pack from the blister pack, the closure cap also including stiffening means located next to a lidding layer of said blister pack in order to reduce flexibility of said blister pack to thereby enhance rupturing of said blister pack.

30. A closure cap having a body portion and a first portion movable relative to the body portion to open the cap, one of the body portion and the first portion carrying a blister pack and the other one of the body portion and the first portion carrying an ejecting member whereby movement of the first portion relative to the body portion ruptures said blister pack and ejects an article contained in said blister pack from the blister pack, the closure cap also including stress concentrating means located next to a lidding layer of said blister pack in order to concentrate stress in an isolated region of said lidding layer to thereby enhance rupturing of said blister pack.