GB2190661A

GB2190661A - Tamper indicating container

Info

Publication number: GB2190661A
Application number: GB08612239A
Authority: GB
Inventors: Frederick Charles Groom; Richard Hundson Bebb
Original assignee: Lin Pac Mouldings Ltd
Current assignee: Linpac Mouldings Ltd
Priority date: 1986-05-20
Filing date: 1986-05-20
Publication date: 1987-11-25
Also published as: GB8612239D0

Abstract

A container assembly has a lid 2 with a skirt 9 having an internal flange 13 and an open topped container 1 whose sidewalls 3 bear spring leaf elements 4 which are biased outwardly of the container within the skirt 9. The flange 13 snap engages over the spring leaf 4 to retain the lid. The skirt 9 has a line of weakness 15 which permits the flanged part 13 of the skirt to be ripped away to permit removal of the lid. The assembly is preferably moulded in plastics and the lid may be hinged to the container. In a modification part of the spring leaf 4 may be ripped away to disengage the spring leaf from the flange 13 for removal of the lid. <IMAGE>

Description

SPECIFICATION A container assembly and a method of manufacturing such an assembly Technical field and background art The present invention relates to a container assembly and a method of manufacturing such an assembly; more particularly it concerns container assemblies ofthetype having a container with an upstanding side wall which forms an open top and a lid which is fitted to the container to close the open top. The invention was primarily developed for plastics moulded container assemblies as may be used, for example, in the storage, transportation and serving or dispensing of foodstuff such as icecream, biscuits orthe like.With container assemblies ofthe type mentioned there is often a requirement that the produce or goods packaged in the assembly are not subjected to unauthorised access so that the contents can be tampered with or removed or, if such unauthorised access has taken place, then it will be apparent upon examination ofthe assembly.

Having this latter requirement in mind, it is an object of the present invention to provide a container assembly and method of manufacturing such an assembly which can be produced simply and economicallyand which will reveal if the lid is subjected to unauthorised removal andtherebythe contents possibly tampered with.

Statement ofinvention andadvantages According to the present invention there is provided a container assembly comprising a lid having a downwardly extending skirtwith an internal flange and an open topped container,the open top being formed by upwardly extending side wall means; the side wall means having, on the outside of the container, at least one downwardly extending spring leafwhich is biased outwardly of the container, the spring leaf and upper edges ofthe side wall means being received within the skirt so thattheinternalflangeoftheskirtsnapengageswith the spring leaf on the outside of the conta inerto retainthe lid asaclosureforthe open top, and wherein weakened regions are provided which permit part of the assembly to be ripped away and the skirtto be disengaged from the spring leaf so that the lid can be removed to open the top.

Further according to the present invention there is provided a method of manufacturing a container assembly which comprises forming a lid having a downwardly extending skirtwith an internal flange and an open topped container in which the open top is formed by upwardly extending side wall means; providing on the side wall means on the outside of the container a downwardly extending spring leaf which is biased outwardly of the container; loading the containerwith its required contents; fitting the lid to close the top by locating the spring leaf and upper edge of the side wall means within the skirt so thatthe internal flange of the skirt snap engages with the spring leaf on the outside of the container, and which further comprises providing weakened regions which permit part of the assembly to be ripped away for disengaging the skirt from the spring leaf to remove the lid from the open top.

The container which forms part ofthe assembly will usually be ofrectangularshape with four upstanding side walls, however the container can be ofanyshape,forexample,polygonal,circularoroval so thatthe sidewall means can comprise one or more upstanding side walls. Afeature ofthe invention isthatthe sidewail orwalls are provided with one or more downwardly extending spring leaves which are normally biased outwardly of the container. The lid when fitted or moved to close the dontainer is intended to displace the spring leaf or leaves against their biasing and, as the flange on the skirt of the lid snap engages overthe spring leaf our leaves, the latter are biased outwardly into engagement with the skirt.As a consequence, if an attempt is made to prise or lever the skirt outwardly and upwardly off the container, the spring leaf or leaves can move outwardly in unison with the skirt underthe spring biasing ofthe leaves to maintain the engagement between the leaves and the skirt.

Naturally if sufficient ieverage is applied to the skirt to force the lid from the container, there is likelyto be damagetotheassemblywhichwill beapparentand indicate unauthorised access. However access can be made readily available by ripping away part ofthe assembly so that the skirt disengages from the spring leaforleavesto such an extentthatthe lid can easily be removed- naturallywhen partofthe assembly has been ripped away it will be readily apparentthatthere has been access to the container and in this way it is believed that unauthorised access ortampering with the container contents will be alleviated.

The container assembly of the present invention was primarily developed for manufacture by moulding in plastics material although it will be realised that the invention may be applicable to lidded containers of other material such as cardboard orthin metal sheet.

Preferably the spring leaf or leaves extend downwardly from the upper edge or edges of, and over the outside of, the container side wal Is. The leaf or leaves are conveniently formed as an extension of the side wall with which they are respectively associated. With this in mind, the spring leaf or leaves can initially be formed to extend from the upper edges of their respectively associated side walls so that when the lid is fitted (and immediately before the flange ofthe skirt snap engages with the leaf or leaves) those leaves are displaced inwardly towards their respectively associated side walls and against the biasing which will be provided by the natural resilience ofthe material from which the container is formed.This latter means offorming the spring leaf or leaves is particularly suitable with a material such as plastics where the spring leaf or leaves can initial Iy be mou Ided so that they subtend a relatively large angle (say 90" or greater) with the side walls from which they respectively extend and, when the lid is fitted, abutment of the spring leaves with the skirt maintains the respective spring leaves against their natural biasing so they subtend a relatively accute angle with the side walls from which those leaves respectively extend.

Preferably the material of the assembly is provided with one or more predetermined lines ofweakness which permits the relevant partto be ripped away so thatthe skirt is disengaged from the spring leaf or leaves and the lid can be removed. These predetermined lines ofweakness are conventiently formed by an array of perforations or by relatively thin regions in the wall thickness of the material.

Although the part of the assembly which is to be ripped away must permit disengagement of the skirt from the spring leaf or leaves, it is preferred thatthe lid is nevertheless re-usable to the extent that access can be made available to the contents ofthe container and thereafterthe open top closed (as, for example, may be required forthe spasmodic serving of icecream from the container). With this latter feature in mind it is preferred that an overlapping part between the skirt and the leaf or leaves is that whichisweakenedto be ripped away. Although the or part ofthe spring leaf or leaves can be arranged to be ripped away from within the skirt, it is preferred that a hem part of the skirt (from which the internal flange projects) can be ripped off to release the lid.

Thepartoftheassemblywhich isto be ripped away may be provided with a tag which can be gripped to facilitate the removal of that part. Itwill be appreciated thatthe part ofthe assembly which is ripped awaytofacilitate removal of the lid does not, necessarily, have to extend around the full periphery ofthe skirt and it may be, for example, with a rectangular container that it is sufficient to tear-off part of the skirt along two adjacent sides of the open topforthelidto be removed.

Generallythe lid and container will be formed as separate components. Howeverthe invention can be applied to assemblies in which the lid is hinged to the container so thatthe skirt extends downwardlyfrom the non-hinged edges of the lid for engagement with appropriately located spring leaf or leaves on the container.

Drawings One embodiment of a container assembly constructed in accordance with the present invention will now be described, by way of example only, with reference to the accompanying illustrative drawings in which Figure lisa section through part of a sidewall of the container as initiallyformed; Figure2shows the side wall section of Figure 1 with the upperpartthereoffolded outwardly and downwardly to form a spring leaf;; Figure3showsthe container side wall section of Figure 2 having a lid fitted thereto, and Figure 4 is a perspective view of a rectangular container with side walls and spring leaves formed as shown in Figure 2 and a lid which is to be fitted to the container in the manner shown in Figure 3.

Detailed description of drawings The container assembly illustrated is primarily intended forthetransport, storage and dispensing of foodstuff and has a container 1 and lid 2 which are injection moulded as separate components in plastics material. The container lisa generally rectangular comprising a base 2 and fou upstanding sidewalls3. Each sidewall 3 has associated therewith a spring leaf 4which, as shown in Figure 4, extends downwardly and outwardly from the upper edge 5 of its respective side wall.

As shown in Figure 1, each spring leaf4 is moulded initially as an extension of its respective side wall 3 with a thinned side wall region 6 being provided between each wall part 3 and its associated leaf 4. In Figure 1 the leaf4 is shown moulded coplanarwith the sidewall 3 but it will be appreciated thatthis initial mouldingconfiguration is not essential and in practice, to facilitate the design of a moulding tool, the leaf4 may, as initially moulded, subtend an angle of approximately 90" with the exterior of the side wall 3. Following the moulding, the spring leaf4 isfolded aboutthe region 6 outwardly of the container and downwardly in the direction of arrowAto be doubled over the side wall 3 (as shown in Figure 2).In this latter configuration it will be apparent that the natural resilience of the plastics material in the folded region 6 will cause the spring leaf 4to be biased outwardly and upwardly relative to the side wall 3 as shown by the arrow B. In its folded condition the weakened region 6 forms the upper edge 5 ofthe sidewall 3.

The lid 2 is a substantially complementary fit over the open top 7 of the container 1 and has a recessed closure sheet 8and a downwardly extending peripheral skirt 9. An internal peripheral channel 10 (see Figure 3) is formed between the skirt 9 and sheet 8within which the upper marginal edge part ofthe side walls 3 and their respectively associated spring leafs 4 are received so thatthe recessed sheet 8 abuts the internal face of the side walls 3 to form a seal 11 as shown in Figure 3.The skirt9 hasa hem 12from which extends an internal peripheral flange 13.As readily seen from Figure 3, when the lid 2 is fitted to the container 1, the upper marginai edge part ofthe side walls 3 and the spring leaves 4 are pushed into the channei 10 and during thisfitting the spring leaves 4 are displaced (by abutment with the flange 13) inwardly towards the side walls 3 (and against their spring biasing) until the lower edges 14 ofthe spring leaves snap engage overthe internal flange 13 and the spring leaves are biased into abutment with the skirt 9. With this arrangement, and as will be apparent from Figure 3, if an attempt is made to lever the flange 13 and skirt 9 outwardly ofthe container sidewall 3 in an attemptto clearthe spring leaf4,the biasing of this spring leaf 4will cause that leaf to move outwardly with the skirtto maintain its engagement therewith and thereby alleviate unauthorised removal of the lid 2 from the container.

In moulding the lid 2 a peripheral line ofweakness 15 is provided between the upper part of the skirt and its hem 12. This line of weakness is conveniently formed by a thinning of the plastics and extends downwardly at 1 5a (see Figue 4) to the lower edge of the skirtthrough the flange 13. Extending from the hem 12 adjacent to the weakened region 1 5a is a tag 16 which can be gripped to rip away the hem 12 alongtheweakened lines 15aand 15aroundthe periphery ofthe lid. With the hem and flange 13thus removed the lid 2 can simply be lifted offthe container 1. It will be noted that with the hem 12 ripped away to disengage the flange from the spring leaves 4, sufficient depth of channel 10 remains for the lid to be press fitted to the container.

Claims

1. A container assembly comprising a lid having a downwardly extending skirt with an internal flange and an open topped container, the open top being formed by upwardly extending side wall means; the side wall means having, on the outside ofthe container, at least one downwardly extending spring leaf which is biased outwardly of the container, the spring leaf and upper edges of the side wall means being received within the skirt so that the internal flange of the skirt snap engages with the spring leaf on the outside ofthe containerto retain the lid as a closureforthe open top and wherein weakened regions are provided which permits part ofthe assemblyto be ripped away and the skirt to be disengaged from the spring leaf so that the lid can be removed to open the top.

2. An assembly as claimed in claim 1 in which the spring leaf extends from the or an upper edge of the sidewall means.

3. An assembly as claimed in claim 2 in which the spring leaf is initially formed, substantially, as a continuation of the side wall means.

4. An assembly as claimed in any one ofthe preceding claims in which the weakened regions are located so that at least part of the skirt from which the internal flange projects can be ripped away so that the internal flange disengages from the spring leaf to permit the lid to be removed.

5. An assembly as claimed in claim 4 in which the weakened regions permit a hem part of the skirt to be ripped away so that a further part of the skirt remains on the lid to extend overthe side wall means.

6. An assembly as claimed in either ciaim 4 or claim 5 in which the weakened regions extend substantially around the periphery of the skirt.

7. An assembly as claimed in either claim 1 or claim 2 in which the weakened regions are located so that at least part of the spring leaf can be ripped away and said part ofthe spring leaf disengages from the internalflangetopermitthelidto be removed.

8. An assembly as claimed in any one ofthe preceding claims and comprising at least two spring leafs which are peripherally spaced on the container and snap engage with parts of the internal flange of the skirt.

9. An assembly as claimed in anyoneofthe preceding claims in which the container is substantially of rectangular shape and spring leaves are located on atleasttwo sidewallsofthecontainer.

10. An assembly as claimed in any one of the preceding claims in which the weakened regions comprise at least one line of weakness formed by a relatively thin region or an array of perforations in the material which is to be ripped away.

11. An assembly as claimed in any one ofthe preceding claims in which the part ofthe assembly which is to be ripped away is provided with a tag.

12. Anassemblyasclaimed inanyoneofthe preceding claims in which the lid is completely removable from the containerwhen the skirt is disengaged from the spring leaf.

13. An assembly as claimed in any one of claims 1 to in which the lid is hinged to the containerand the skirt extends downwardlyfrom a non-hinged edge region of the lid.

14. Anassemblyasclaimed in any one ofthe preceding claims and moulded in plastics material.

15. A container assembly substantially as herein described with referenceto the accompanying illustrative drawings.

16. A method of manufacturing a container assemblywhich comprises forming a lid having a downwardly extending skirt with an internal flange and an open topped container in which the open top is formed by upwardly extending sidewall means; providing on the side wall means on the outside of the container a downwardly extending spring leaf which is biased outwardly ofthe container; loading the container with its required contents; fitting the lid to close the top by locating the spring leaf and upperedgeofthesidewall meanswithintheskirtso that the internal flange ofthe skirt snap engages with the spring leaf on the outside ofthe container, and which further comprises providing weakened regions which permit part of the assembly to be ripped away for disengaging the skirt from the spring leaf to remove the lid from the open top.

17. Amethod as claimed in claim l6which comprises providing the spring leafto extend from the upper edge of the side wall means.

18. A method as claimed in claim 17 which comprises forming the spring leaf as an extension of the side wall means and displacing the spring leafto its downwardly extending condition during fitting of the lid to close the top whereby the resilience ofthe material between the side wall means and the spring leaf biases the spring leaf outwardly of the container.

19. A method as claimed in claim 18which comprisesinitiallyformingthespring leaf on the sidewall means so that it subtends an angle of at least 90" with the side wall from which it extends.

20. A method as claimed in any one of claims 16 to 19 which comprises forming the weakened regions in the lid so that at least partofthe skirtcan be ripped awayforthe internal flange to disengage from the spring leaf.

21. A method as claimed in anyone of claims 16 to 19 which comprises forming the weakened regions in the container so that at least part ofthe spring leaf can be ripped awayforthe internal flange to disengage from the spring leaf.

22. A method as claimed in anyone ofclaims 16 to21 which comprisesformingtheweakened regions by at least one line of weakness of a relativelythin region oran array of perforations in the material which isto be ripped away.

23. A method as claimed in any one of claims 16 to22which comprises moulding the containerand lid in plastics material.

24. Amethod of manufacturing acontainer assembly substantially as herein described.