CONTAINERS AND CLOSURES

Abstract

There is a resealable closure for plastic containers of a type having a mouth (7) formed with an inner neck bore (8) and spaced apart neck stubs (9) arranged around the outside of the neck. The closure in one position of use has a top panel (1), a peripheral downwardly extending skirt (2) with inwardly directed locking lugs (3) and an inner spigot seal (4) dimensioned for an interference fit into said neck bore (8). The closure is adapted to removably seal the container by push fitting the spigot seal (4) into engagement with said neck bore and subsequently locking the closure by rotation to a position where the locking lugs (3) align under the neck stubs (9).

Description

This invention relates to containers and resealable closures. More particularly although not exclusively an improved plastic container and radial seal closure is disclosed.

Resealable closures for containers are well known in the art. Existing containers and closures commonly use threads and conventional compressive seals which have problems with plastic creep. When such closures are tightened the stressed components relax over time and deform with the result that that the seal may be compromised.

It is therefore an object of this invention to provide an improved form of container and closure which ameliorates the aforementioned problem. Other advantages in manufacturing cost and service life may also be realised.

In one broad aspect the invention discloses a resealable closure for plastic containers of a type having a mouth formed with an inner circular neck bore and spaced apart neck stubs arranged around the outside thereof, said closure in one position of use having a top panel, a peripheral downwardly extending skirt with inwardly directed locking lugs and an inner spigot seal dimensioned for an interference fit into said neck bore whereby said closure is adapted to removably seal said container by push fitting the spigot seal into engagement with said neck bore and subsequently locking the closure by rotation to a position where the lugs align under said neck stubs.

Preferably the container and closure are moulded from a resiliently deformable plastic.

It is further preferred that the neck stubs and locking lugs are dimensioned and positioned to cause distortion upon locking the closure whereby frictional resistance holds said closure at the locked position.

It is further preferred that the underside faces of said neck stubs are substantially flat to evenly engage the locking lugs.

It is further preferred that the outside surfaces of the container and closure are shaped, textured or otherwise marked in a manner to provide a visual or tactile indication of a locked or unlocked configuration of said closure.

It is further preferred that said closure is adapted to move in either rotational direction between the locked and unlocked positions.

Two currently preferred embodiments of the invention will now be described with reference to the attached drawings in which:

FIG. 1 is an elevation view of a resealable closure in accordance with a first embodiment of said invention,

FIG. 2 is a cross-sectional view along the lines A-A of FIG. 1,

FIG. 3 is a vertical cross-sectional view through the centre of the closure of FIG. 1,

FIG. 4 is an elevation view of a container according to said invention,

FIG. 5 is a plan view of the container neck,

FIG. 6 is a horizontal cross-sectional view through the container and fitted closure when in the unlocked position,

FIG. 7 is a vertical elevation view of the closure when fitted to the container in the locked position,

FIG. 8 is a view similar to FIG. 6 but with the closure in the locked position,

FIG. 9 is an elevation view of the closure fitted to the container in the locked position,

FIG. 10 is a plan view of a resealable closure in accordance with a second embodiment of the invention,

FIG. 11 is a cross-sectional elevation view of the resealable closure of FIG. 10

FIG. 12 is a cross-sectional elevation view of a container for use with the closure of FIG. 10,

FIG. 13 is a plan view of the container of FIG. 12,

FIG. 14 is a cross-sectional view of the container of FIG. 12 with the closure of FIG. 10 fitted,

FIG. 15 is a plan view of the assembles closure and container with said closure in the unlocked position, and

FIG. 16 is a view similar to FIG. 15 but with the closure in the locked position.

Referring first to FIGS. 1 to 3 the closure may comprise a flat upper panel 1 with side panels 2 which are formed into a hexagonally shaped skirt. As best shown in FIG. 2 the inside walls of the side panels have inwardly protruding locking lugs 3. The inside surface of the upper panel 1 is also formed with a central spigot seal 4. This seal is shaped and dimensioned for an interference sealing fit with a container 5 as discussed in more detail hereunder.

The container as shown in FIGS. 4 and 5 may also be hexagonally shaped with outer wall panels 6 to match the profile of the closure. The upper end of the container is formed into a neck 7 with an annular inner bore 8. The neck is formed around the outside with stubs 9 which have underside locating flats 10. These stubs are positioned for locking engagement with the aforementioned lugs 3 in the closure.

In use the closure is fitted to the container by placing it over the neck with the locking lugs 3 and neck stubs 9 initially offset to clear each other as shown in FIG. 6. The spigot seal is then pushed into the neck bore 8 to the position shown in FIG. 7. To complete the assembly the closure is subsequently locked in place by rotating it on the container so that the locking lugs engage under the locating flats of the neck stubs 9 as shown in FIG. 8. The relative locations of these lugs and stubs are such that the closure panels are distorted during this engagement. This provides a degree of frictional resistance to releasably retain the closure at the locked position. The position of the lugs and stubs are preferably also arranged so that when engaged the outer surfaces of the panels 2 align with the container panels 6 as shown in FIG. 9 to provide a visual or tactile indication of the locked closure. Undercuts 10 may also be formed across the aligned panels 2 and 6 for labels or the like.

With the second embodiment as shown in FIGS. 10 to 14 the closure, indicated generally as 11, may comprise a flat upper panel 11A with side panels 12 which are formed into a rectangular skirt. As best shown in FIG. 11 the inside walls have inwardly protruding locking lugs in the form of catch plates 13. The inside of the upper panel 11 is also formed with a central spigot seal 14. This seal is shaped and dimensioned for an interference sealing fit with the container 15A as described in more detail hereunder.

The container as shown in FIGS. 12 to 14 is rectangular in shape to preferably match the profile of the closure. The upper end of the container is formed into a neck 16 with an annular inner bore 17. The neck is formed around the outside with protruding cam shaped stubs 18 which have underside engagement surfaces 19.

These stubs 18 are positioned for locking engagement with the aforementioned catch plates 13 on the closure. Located under the lugs 18 is a square locating plate 20.

In use the closure of this second embodiment is fitted to the container 15A by placing it over the neck 16 with the catch plates 13 and cam lugs 18 initially offset to clear each other as shown in FIG. 15. The spigot seal 14 is then pushed into the neck bore 17 and the closure locked in place by rotating it to be in register with the container. In this position the catch plates 13 engage under respective cam lugs 18 as shown in FIG. 16. The matching rectangular profiles of the closure and container preferably align at this position to show that they are in locking engagement.

During initial assembly the closure is adapted to be pressed into place or “jumped on” following fitting and for this reason the catch plates 13 are preferably tapered to snap fit over the cam lugs. The closure can thus be quickly locked onto the container during initial assembly without rotation. Gas pressure release from the container can be controlled by contouring the profiles of the cam lugs 18 and catch plates 13.

It will thus be appreciated that this invention at least in the form of the embodiments disclosed provides an improved form of closure and container. A novel radial sealing arrangement is disclosed which is less subject to plastic creep and leakage than conventional prior art compressive seals. Clearly however the examples described are only the currently preferred forms of the invention and a range of modifications may be made which would be apparent to a person skilled in the art. For example the shape and configuration of the closure, spigot seal and container may be changed from the designs shown. The closures may even be circular when used on paint drums for example. The invention is also not limited to any specific material for the closure or container although a readily mouldable and low cost plastic such as P.E.T. is currently preferred. This would provide good O2 resistance and with light tightening there would be no threads to bind up if the container is hot filled.

Claims

1. A resealable closure and a container, the container having a neck with an inner bore and spaced apart stubs arranged around the outside thereof, said closure in one position of use having a top panel, a peripheral downwardly extending skirt with inwardly directed locking lugs and a spigot seal formed on an inside surface of said top panel dimensioned for an interference fit into said bore whereby the closure is adapted to removably seal said container by push fitting the spigot seal into engagement with said bore at an unlocked position where the lugs are offset to clear said neck stubs and subsequently rotating said closure to a locked position where the lugs align under said neck stubs.

2. The resealable closure and container as claimed in claim 1 wherein the stubs and locking lugs are dimensioned and positioned to cause distortion upon rotation said closure to said locked position whereby frictional resistance holds the closure at said locked position.

3. The resealable closure and container as claimed in claim 1 wherein said locking lugs and stubs are shaped to enable said closure to move in either rotational direction between said locked and unlocked positions.

4. The resealable closure and container as claimed in claim 1 wherein said stubs have locating flats for engagement with the locking lugs.

5. The resealable closure and container as claimed in claim 1 wherein the closure has a profile which matches the shape of said container when at said locked position.

6. The resealable closure and container as claimed in claim 1 wherein said locking lugs are in the form of tapered catch plates to enable initial locking of the closure onto the container without rotation.

7. The resealable closure and container as claimed in claim 5 wherein said profile is hexagonal.

8. The resealable closure and container as claimed in claim 5 wherein said profile is rectangular.

9. A resealable closure for a container, said closure in one position of use having a top panel, a peripheral downwardly extending skirt with inwardly directed locking lugs and a spigot seal formed on an underside surface of said top panel.

10. The resealable closure as claimed in claim 9 wherein said locking lugs are in the form of tapered catch plates.