AU2006225183B2

AU2006225183B2 - Container closure

Info

Publication number: AU2006225183B2
Application number: AU2006225183A
Authority: AU
Inventors: David Alexander Woinarski
Original assignee: Innovative Design Co Pty Ltd
Current assignee: Innovative Design Co Pty Ltd
Priority date: 2003-05-30
Filing date: 2006-09-29
Publication date: 2009-09-17
Anticipated expiration: 2024-05-28
Also published as: AU2006225183B8; AU2006225183A1

Description

AUSTRALIA Patents Act 1990 COMPLETE SPECIFICATION STANDARD PATENT Applicant: Innovative Design Co Pty Ltd Invention Title: CONTAINER CLOSURE The following statement is a full description of this invention, including the best method of performing it known to me/us: 2 CONTAINER CLOSURE Technical Field An improved closure for a container is disclosed, the closure being adapted in a 5 manner that ameliorates entrapment at an underside of the closure of flowable substances that may be stored within the container. Background Art Plastic and metal containers such as pails are used for holding chemicals, many 10 of which are flowable including liquids such as paints, solvents and oils; flowable solids such as powders etc. Some known closures for such containers include a so-called stacking skirt, being a wall that protrudes from an underside of the lid around and adjacent to its periphery. The stacking skirt can engage with an internal step or rebate defined in an interior of the container adjacent to its opening, whereby loading forces 15 applied to the closure can be transmitted via the stacking skirt to the container. For example, AU 488194 discloses a container lid 11 that is provided with a stacking wall 31 that engages, at its distal end, an internal peripheral step defined inside the container 10. However, as clearly shown in Figure 8 of AU 488194, the orientation of the wall 31 defines a groove or channel 34 at the underside of lid 11, the groove 20 extending around the lid adjacent to the wall 31. This groove or channel can act as a trap for flowable substances that may be stored within the container, especially for a liquid that has a viscosity that results in a surface tension tending to cause it to be retained in the groove or channel. WO 2002/30780 discloses a container lid 11 that is provided with two different 25 stacking walls. In Figures 2 and 5, a vertical stacking wall 40 engages, at its distal end, an internal peripheral step 24 defined inside the container at wall 15. This wall is connected to the wall 42 by discrete webs 43. In Figure 4, the distal end of an angled stacking wall 40 engages the internal peripheral step 24. In each case a trap for flowable substances is defined between the stacking skirt and the wall 42. The webs 43 in actual 30 fact provide an enhanced entrapment function. Similarly, WO 2004/106185 discloses a container lid 11 that is provided with a stacking skirt 52 that engages, at its distal end 52A, an internal peripheral step 54 defined inside the container 10. Again, as clearly shown in Figure 3 of WO P61862 3 2004/106185, the orientation of the skirt 52 defines a groove or channel at the underside of lid 11 that extends around the lid adjacent to the skirt 52, and that can act as a trap for flowable substances that may be stored within the container. As an example of an entrapment problem, when the container is used to store 5 paint, the lid may be removed to add a tinting agent ("tint"). When the lid is replaced, and when the now closed container is shaken to disperse the tint, the tint can become entrapped in such a groove or channel, or against any webs, and not be dispersed in the paint. The resulting paint in the container can then have an incorrect colour for an unsuspecting user. 10 The reference to the prior art documents above is not an admission that the documents form a part of the common general knowledge of a skilled person in the art, either in Australia or elsewhere. Summary of the Present Disclosure 15 A closure for a container is disclosed that comprises a base and a peripheral wall, with a rim forming an upper margin of the wall and surrounding an opening of the container. The closure for the container comprises a wall that is adapted to extend across and to overlie the container opening when the closure is mounted to the container. The 20 wall extends inwardly from an inside wall of an inverted peripheral channel section of the closure that is adapted to mount to the container rim. A peripheral skirt projects at an obtuse angle from the closure wall at or adjacent to its junction with the channel section and such that a distal end of the skirt can engage a wall formation within the container when the closure is mounted thereto. 25 The peripheral skirt can function as a stacking skirt, as defined in the Background. However, because the peripheral skirt projects from the closure wall at or adjacent to its junction with the channel section, to a distal end that engages a container wall formation, no groove or channel is defined in the closure underside that may then act as a trap for a flowable substance stored within the container. 30 In one form the peripheral skirt can project from the closure wall at the junction with the channel section. When the closure is mounted to the container, the skirt distal end can engage an internal peripheral step especially defined in the container wall. This step can help to P61862 4 promote the skirt stacking function. In one form the inverted peripheral channel section can have, in cross-sectional profile, an inverted general U-shape. Then, the closure wall can extend laterally from an inside stem of the U-shape, and the rim can be received within the U-shape so as to be 5 surrounded at is periphery by an outside stem of the U-shape. A shorter peripheral skirt may be provided that projects from an inside face at the inverted U-shape around the periphery of the closure underside. The shorter skirt can be adapted to engage an inside surface of the rim when the closure is mounted to the container, to promote a more secure mounting of the closure to the container. 10 Further, the outside stem of the U-shape can define a skirt that is inwardly adapted (eg. shaped) so as to interlockingly engage with a formation defined externally on the rim, when the closure is mounted to the container. Brief Description of the Drawings 15 Notwithstanding other embodiments which may incorporate some or all of the features as outlined in the Summary, a number of specific closure embodiments will now be described, by way of example only, with reference to the accompanying drawings in which: Figure 1 shows a side view of an assembled closure and container; 20 Figure 2 shows a side sectional view through part of the assembled closure and container of Figure 1, the view showing a first closure embodiment in cross-sectional profile; Figure 3 shows a view similar to Figure 2 but for a second closure embodiment; 25 Figure 4 shows a view similar to Figure 2 but for a third closure embodiment; Figure 5 shows a view similar to Figure 2 but for a fourth closure embodiment; Figure 6 shows a view similar to Figure 2 but for a fifth closure embodiment. Detailed Description of Specific Embodiments 30 Referring to Figure 1, a container having a closure mounted thereto is generally depicted. The closure is provided in the form of a lid 10 and the container is provided in the form of a pail 12. Typically the lid and pail are circular. The pail and lid may each be moulded from polypropylene or high density P61862 5 polyethylene. The pail may be moulded in any desired size and may have a volumetric capacity in the order of eg. 0.5 to 20 litres. The pail may also be formed from a metal material. In addition, the lid arrangements as hereafter described can be used with both tapered (Figure 1) and straight-sided pails. 5 The pail 12 has a base 13 which is sized so that it can be located within a recess defined in the lid. A peripheral wall 15 extends up from the base, with a rim 16 forming an upper margin of the wall 15 and surrounding an opening of the pail. A peripheral flange 17 protrudes out from the pail adjacent to but set lower than a distal edge 16A of the rim 16. A number of discrete finger recesses 18 may be provided 10 around the flange 17 to help facilitate removal of the lid from the pail (eg. by manually pealing it off). The lid in each of the embodiments of Figures 1 to 6 comprises a generally flat central wall 19 which is generally sized to cover the majority of the opening when the lid is mounted to the pail, but which may also be sized so that the base of an overlying 15 pail can be positioned thereat. This then enables a number of pails to be stacked one upon another. As shown in each of Figures 2 to 6, the wall 19 extends inwardly from an inside wall portion 20 that is part of an inverted U-shaped peripheral channel 22 that defines an external part of the lid, and that adapts the lid for mounting to the rim 16. 20 A peripheral stacking skirt 24 projects from the wall 19 at ajunction 26 with the wall portion 20, although it may alternatively project from wall 19 at a location that is adjacent to (ie. inset from) the junction. When the lid is mounted to the pail, a distal end 28 of the skirt 24 is shaped to engage an internal peripheral step 30 defined in the pail wall 15, the step being located within the pail. 25 Because the skirt 24 projects from the wall 19 at (or inset from) the junction 36, and because the skirt's distal end 28 engages the pail wall 15 at step 30, no groove or channel is defined in the lid underside that may then act as a trap for a flowable substance stored within the pail. In Figure 2 it will be seen that the rim 16 is received within the U-shaped 30 channel 22, such that it is surrounded at is periphery by an outside skirt 32 of the U shaped channel. The skirt 32 comprises an inwardly projecting ledge 34 that interlockingly engages with a bead formation 36 defined externally on the rim 16 when the closure is mounted to the container. P61862 6 A shorter peripheral skirt 38 may also be provided to project from an inside face of the U-shaped channel around the periphery of the lid underside. When the closure is mounted to the container the shorter skirt can be adapted to interlockingly engage an internally projecting peripheral bead 40 defined adjacent to the rim distal end 16A. In 5 this regard, it will be seen that the rim distal end 16A is thus received into a second and smaller inverted U-shaped channel defined between the skirt 32 and the skirt 38. Referring now to Figure 3, where like reference numerals are used to denote similar or like parts, it will be seen that the lid 10 is essentially the same as that shown in Figure 2, however the lid additionally comprises a tear band 42 subtending from and 10 frangibly connected at 43 to a distal end of the skirt 32. The tear band is snugly received in a rebate 44 defined in the flange 17, with a distal end 46 of the tear band engaging a shoulder 48 defined in the rebate 44. Again, no groove or channel is defined in the lid underside. Referring now to Figure 4, where like reference numerals are used to denote 15 similar or like parts, it will be seen that the lid 10 is again essentially the same as that shown in Figure 3, however in this case the flange 17' is modified such that only the distal end 46 of the tear band engages the shoulder 48' defined in the flange. Again, no groove or channel is defined in the lid underside. Referring now to Figure 5, where like reference numerals are used to denote 20 similar or like parts, it will be seen that the lid 10 is essentially the same as that shown in Figure 2. However, in place of the shorter peripheral skirt 38, an annular hinge region 50 is defined across the U-shaped channel. This region can provide additional flexure during lid mounting to and removal from the pail. Again, no groove or channel is defined in the lid underside. 25 Referring now to Figure 6, where like reference numerals are used to denote similar or like parts, it will be seen that the lid 10 is essentially the same as that shown in Figure 2. However, the shorter peripheral skirt 38' is modified to project more vertically. Also, the bead 40 is replaced with a peripheral bump 52. Thus, the engagement between skirt 38' and bump 52 is frictional rather than interlocking. Again, 30 no groove or channel is defined in the lid underside. In the embodiments described the lid is formed from deformable and/or deflectable materials to facilitate its mounting onto and removal from the pail. On the other hand, and as required, the pail may be formed from deformable or non-deformable P61862 7 materials such as plastic or metal etc. Whilst a number of embodiments have been described, it will be appreciated that the lid arrangements described can be embodied in many other forms. In the claims which follow and in the preceding description, except where the 5 context requires otherwise due to express language or necessary implication, the word "comprise" or variations such as "comprises" or "comprising" is used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments. 10 P61862

Claims

1. A closure for a container that comprises a base and peripheral wall, with a rim forming an upper margin of the wall and surrounding an opening of the container; 5 the closure comprising a wall that is adapted to extend across and to overlie the container opening when the closure is mounted to the container, the wall extending inwardly from an inside wall of an inverted peripheral channel section of the closure that is adapted to mount to the container rim; wherein a peripheral skirt projects at an obtuse angle from the closure wall at or 10 adjacent to its junction with the channel section and such that a distal end of the skirt can engage a wall formation within the container when the closure is mounted thereto.

2. A closure as claimed in claim 1, wherein the peripheral skirt projects from the closure wall at the junction with the channel section and, when the closure is mounted 15 to the container, the skirt distal end engages an internal peripheral step defined in the container wall.

3. A closure as claimed in claim I or 2, wherein the inverted peripheral channel section generally has, in cross-sectional profile, an inverted U-shape, whereby the closure wall 20 extends laterally from an inside stem of the U-shape, and whereby the rim is received within the U-shape so as to be surrounded at is periphery by an outside stem of the U shape.

4. A closure as claimed in claim 3, wherein a shorter peripheral skirt projects from an 25 inside face at the inverted U-shape around the periphery of the closure underside, the shorter skirt being adapted to engage an inside surface of the rim when the closure is mounted to the container.

5. A closure as claimed in claim 3 or 4, wherein the outside stem of the U-shape 30 defines a skirt that is inwardly adapted so as to interlockingly engage with a formation defined externally on the rim when the closure is mounted to the container.

6. A closure for a container, the closure being as defined in any one of claims I to 5 and substantially as herein described with reference to the accompanying drawings. 35 P61862