NZ244899A - Container lid; lid rim includes recesses to enable air in container to be vented - Google Patents

Description

24 4 89 9 NEW ZEALAND PATENTS ACT 1953 COMPLETE SPECIFICATION BgCaiVgD AFTER PROVISIONAL NO: 244899 DATED: 27 October 1992 IMPROVEMENTS IN AND RELATING TO CONTAINER LIDS WE, HUHTAMAKI OY, of Karsamaentie 35, 20360 Turku, Finland, a Finnish company, do hereby declare this invention to be described in and by the following statement: -1- (followed by 1(a)) N.Z. PATENiT OFFICE 27 OCT 1993 24 4 8 •*- 1(a) -BACKGROUND OF INVENTION ;The present invention relates to improvements in and relating to container lids. ;To the present time lids in New Zealand for fruit drink and yoghurt pots have typically utilised a metal foil secured about the top of the pot. ;One of the disadvantages of such metal foil lids is that inevitpJbly when the foil is removed by a user there will be some metal foil left around the pot rim. As well as affecting the flow of material from the pot, this residue of foil most importantly affects the ability of the used pots being recycled. ;It is an object of the present invention in one embodiment to provide a container lid which obviates problems or disadvantages with lids available to the present time and particularly but not exclusively foil lids, or which at least will provide the public with a useful choice. ;Further objects of this invention will become apparent from the following description. ;244899 ;SUMMARY OF INVENTION ;According to one aspect of the present invention there is provided a container lid having a downwardly depending rim adapted in use to be engaged about a corresponding rim of a container and wherein said rim of said lid includes a plurality of recesses to enable air within the container to be vented during the placement of the lid on said container in use and wherein said recesses are provided across the width of an outer wall of said rim. ;According to a further aspect of the present invention there is provided a lid for a container as above defined, said lid having an outwardly extending tab adapted in use to be held to assist the lifting of the lid from a container and wherein disposed relative to the tab is a location means engagable in use with correspondingly positioned location means of adjacent lids so that a stack of said lids with their location means so engaged have their respective tabs substantially aligned. ;According to a still further aspect of the present invention there is provided a lid for a container as defined in either of the preceding paragraphs including a downwardly depending peripheral rim portion having a pair of recesses each acting as a stacking means to facilitate the stacking qf.ZaHtirgRff^H(^|said lids ;2 - FEB 1338 ;RECEIVED ;24 4 8 ;According to a still further aspect of the present invention there is provided a lid as defined in any one of the three immediately above paragraphs and which is formed from at least a first layer of polybutylyene terephthalate based material or similar high temperature heat distortion handling material. ;Further aspects of this invention which should be considered in all its novel aspects will become apparent from the following description given by way of example of possible embodiments thereof. ;BRIEF DESCRIPTION OF DRAWINGS ;Reference is made to the accompanying drawings wherein: ;Figure 1: Shows an underside view of a lid according to one embodiment of the invention; ;Figure 2: Shows an underside view of a lid according to an alternative design of one embodiment of the invention; ;Figure 3: Shows a view along arrows A-A of figure ;- 4 - ;24 4 8 ;Figure 4: Shows a view along arrows B-B of figure ;2; ;Figure 5: Shows a view fror. above of the lid of figure .1; ;Figure 6: Shows very diagrammatically a view of a lid of the present invention in position on a container; ;Figure 7: Shows very diagrammatically a cross-sectional view of a container in position on a lid according to one possible embodiment of the invention. ;DESCRIPTION OF PREFERRED EMBODIMENTS ;Referring to figures 1 and 2 of the accompanying drawings, two alternative designs of lid, 1,1A are shown according to one embodiment of the invention. In the underside views shown, both designs are essentially the same apart from the positioning and/or number of a plurality of vents or recesses 3 disposed about the perimeter. It will be seen that in figure 1, eight vents 3 are provided while in figure 2, nine vents 3 are provided offset in their peripheral positioning about the respective lid. ;- 5 - ;24 4 8 9 9 ;As shown in outline in figure 3, the vents 3 consist of recesses formed or provided in the initial outer wall 5A of the downwardly depending rim 5 (it is to be appreciated that in figures 3 and 4 the lid in its cross-sectional views is shown inverted), with the vent 3 extending down, in use, to the outer stacking recess flA. The vents 3 enable air to escape from the container as the lid 1,1A is placed over the container opening. This release of trapped air facilitates a tight seal of the lid on the container commensurate with the seal required for products previously using foil seals. The offsetting and/or different number of vents 3 also means that by stacking the lids 1,1A in an alternate fashion, the vents 3 do not coincide on alternate lids thus facilitating the abutment of the adjacent lids together in the stack. ;As shown in figures 1 and 2 and in cross-section in figure 4, the downwardly depending rim 5 of each of the lids 1,1A may be provided with a detent or recess 4 which as shown in figure 4 may extend the length of the inner wall 5B of the rim 5. In the embodiment of the invention shown in figures 1 and 2 the detent 4 is positioned diagonally opposite the tab 2 which is used for lifting the lid from the container. Other positions for the detent 4 could be provided subject to the positioning being consistent so that in a stack of lids 1, 1A, the detents 4 will coincide. In this way the ;24 4 89 ;projection 41 which will be formed on the upper side of the lid (see figure 5) will be engagable with the detent 4 of an immediately adjacent lid and in this way the tabs 2 will be always aligned in the stack thus facilitating the lids being lifted off the stack and their placement in the correct position on the container. ;The downwardly dependent peripheral rim 5 of the lids 1/1A is shown provided with inner and outer stacking recesses 8A and 8B thus facilitating the stacking of the adjacent lids 1,1A together in a typical packaging plant where container lids are removed from a stack for placement onto respective containers. ;As indicated in figure 6, a lid 1 is shown positioned over the open end of a container 11 such as a fruit juice or yoghurt pot with the peripheral rim 9 being positioned on a lip or ledge 13 about an upper edge 12 of the container 11. Suitably the lid rim 9 may incorporate a. heat seal lacquer or the like to facilitate its sealing engagement with the ledge 13 while still enabling the lid 1 to be lifted off by a user gripping the outwardly extending tab 2. ;- 7 - ;14 4 8 J ;In the top view of the lid 1A as shown in figure 5, the substantially central area 10 will typically be provided with suitable printing showing product and manufacturer information. A peripheral serrated area 7 may be provided as shown which may facilitate the location together of adjacent lids 1 in a stack and/or provide reinforcement for the lids 1,1A. ;In the top view shown in figure 5 the detent 4 is shown defining an outwardly extending projection 4*, while the vents 3 on the bottom side are shown providing corresponding inwardly directed portions 3^" on the upper surface.

In Figure 7, a base ll1 of a container 11 is shown positioned on the lid 1 as it would in a stack of containers, possibly three or more deep. In such stacks, movement of a container relative to the lid of the container below on which it is sitting, can cause problems. In Figure 7, the lid with its lifting tab 2 and downward peripheral rim 5 is shown having an inner rim 16 defining a central recess 17 within the lid 1 within which the container base 11^" can be a snug fit or at least with a relatively small clearance which will minimise "slop" between the container 11 and the lid 1. In the embodiment shown, the container base 11^" is shown with a downwardly facing rim, projection or leg(s) providing a base support contacting the lid 1 and 24 4 8 9 9 providing a clearance indicated by arrow 20 between the base ll1 of the container 11 and the upper surface of the lid 1. Such a clearance 20 may be desirable in directing the weight of the container 11 and its contents towards the periphery of the lid 1 so as to reduce the weight on the central portion of the lid 1 which could tend to lift the lid 1 around its periphery from the container 11 which it is sealing which would then permit the container contents to egress.

The lid 1,1A may be of any suitable material, possibly being capable of handling high temperatures, and may be formed by any suitable technique. However a moulding from a plastics material may be suitable. A particular plastics material for high temperature capabilities may be a polybutylyene terephthalate based material such as VALOX (trade mark), manufactured by G.E. Plastics Europe, either alone, and/or a polystyrene such as a high impact polystyrene (HIPS). A particular advantage of using such material is that it would be compatible with polystyrene used for the container itself so as to facilitate the recycling of the used lids and containers together and the scrap material resulting from their respective manufacture. 9 244899 Where in the foregoing description reference has been made to specific components or integers of the invention having known equivalents then such equivalents are herein incorporated as if individually set forth.

Although this invention has been described by way of example and with reference to possible embodiments thereof it is to be understood that modifications or improvements may be made thereto without departing from the scope of the invention as defined in the appended claims. r WX PATEiv 24489

Claims (8)

WHAT WE CLAIM IS:

1. A container lid having a downwardly depending rim adapted in use to be engaged about a corresponding rim of a container and wherein said rim of said lid includes a plurality of recesses to enable air within the container to be vented during the placement of the lid on said container in use and wherein said recesses are provided across the width of an outer wall of said rim.

2. A container lid as claimed in Claim 1 wherein said recesses each extend down to an outer stacking recess which enables a plurality of similar lids to be stacked together.

3. A container lid as claimed in any one of the preceding claims wherein in a plurality of said lids the positioning and/or number of said air vent recesses about said rim is alternated to facilitate the stacking of alternate lids together.

4. A lid for a container as claimed in any one of the preceding claims, said lid having an outwardly extending tab adapted in use to be held to assist the lifting of the lid from a container ,.Z. PATENT OFFICE 2 - FEB 1396 "-CEIVEO - 11 - 244899 and wherein disposed relative to the tab is a location means engagable in use with correspondingly positioned location means of adjacent similar lids so that a stack of said lids with their location means so engaged have their respective tabs substantially aligned.

5. A lid for a container as claimed in Claim 4 wherein said location means comprises a detent or recess provided on an inner wall of said rim of said lid.

6. A lid for a container as claimed in any one of the preceding claims including a downwardly depending peripheral portion having a pair of further recesses each acting as a stacking means to facilitate the stacking of a plurality of said lids.

7. A lid as claimed in any one of the preceding claims formed from at least a first layer of polybutylyene terephthalate based material and/or high impact polystyrene.

8. A container lid substantially as herein described with reference to Figure 1, Figures 2 to 5, Figure 6 or Figure 7 of the accompanying drawings. N.Z. PATENT OFFICE 2 - FEB 1996 g/speci i/snm q-p HcCLEIVEl)