AU2004201435B2 - Container and lid assembly - Google Patents

Description

Sent By: HP LaserJet 3100; 92216513; Apr-5-04 6:38PM; Page 4 P/0Rew 1 ReauMn3.2 AusTRAIuA Patents Act 1990 COMPLETE SPECIFICATION STANDARD PATENT Invention Title: Container and lid assembly The following statement is a full description of this Invention, including the best method of performing it known to us: Frmhills Carter Smith Beadle SydneyO0461631 Printed 5 April 2004 (16:50) pag 2 COMS ID No: SMBI-00696786 Received by IP Australia: Time 17:34 Date 2004-04-05 12700960 speci for response 09/02/06 1- Container and lid assembly Field of the invention This invention relates to containers with removable lids of the type typically used in the paint industry, and to lids used with such containers.

Background of the invention Although the container and lid assembly described herein are particularly useful for storing and dispensing paint, it is to be understood that the aspects of the invention may equally well be used in other types of containers as well.

Containers suitable for storing paint must satisfy certain criteria in order to function satisfactorily. Firstly, the container should be reasonably strong to withstand the handling and transportation stresses that such containers often are subjected to. Secondly, the container needs to have a lid which is able to be reasonably easily opened, but then must be capable of being reapplied to the container in order to reseal the container. When the lid is closed, the container should be sealed in a fluid tight manner so that the paint within the container does not evaporate or deteriorate. The opening and closing of the container should not be prevented or made significantly more difficult by the presence of paint on the sealing surfaces of the lid or the container.

The configuration of the open end of many containers is such that paint from brushes tends to clog into the sealing surfaces of the container, which not only wastes paint but obstructs proper sealing and makes reopening of a container more difficult.

Summary of the invention According to one aspect of the invention there is provided a container and lid assembly, the container including a generally cylindrical body having an open mouth, a generally annular flange extending radially inwardly from an upper edge 12700960 speci for response 09/02/06 -2of the container, a downwardly extending skirt depending from a radially inner edge of the flange and a bead formed on a lowermost edge of the skirt, a radially inner face of the skirt and/or the bead forming a sealing surface, the lid including a generally disc-shaped body, the lid having a channel-shaped annular groove formed therein, a radially outer surface of the channel-shaped annular groove defining a sealing surface adapted to seal with the sealing surface of the container, a radially outer surface of an outer wall of the channel-shaped annular groove defining an outer wall groove adapted to receive the bead when the lid is operatively installed on the container and wherein the outer wall of the channel-shaped annular groove has a region of increased wall thickness at least at an inner wall portion of the outer wall positioned below the outer wall groove, to increase the hoop strength of the outer wall in the region.

In one embodiment, the outer wall of the channel-shaped annular groove has a region of relatively reduced wall thickness in the vicinity of the outer wall groove.

Suitably, the lower part of the outer wall groove includes an outer surface that slopes outwardly and downwardly towards the region of increased wall thickness. The region of relatively increased wall thickness may include a lower edge that slopes downwardly and inwardly towards a lower part of the channel shaped annular groove and may further include a container and lid assembly wherein the region of increased wall thickness includes an inner wall portion which extends outwardly and downwardly from the region of the outer wall groove. This can facilitate insertion of the lid into an operative position on the container as the lower edge can slide over the bead of the container.

The outer wall groove is adapted to receive the bead on the container to assist in locating and holding the lid in position on the container. The outer wall groove is preferably dimensioned to be wider than the thickness of the bead to allow some play in the nesting of the bead within the outer wall groove. The lid preferably has an outwardly extending lip which overlies the flange when the lid is operatively 12700960 speci for response 09/02/06 -3installed on the container.

The bead is preferably located radially inwardly of the skirt, the bead defining a wiping surface against which a brush may be wiped. The skirt is preferably vertical, or near vertical. The flange may be horizontal, or sloped upwardly or downwardly in a radially inward direction.

Preferably the container and the ring are both formed of a sheet metal material. The ring may be joined with leak-tightness to the upper edge of the container in a rolled and folded seam arrangement.

The lid is preferably formed from a resilient plastics material, and dimensioned, so that when the lid is operatively installed on the container, the resilience of the material from which the lid is formed will urge the sealing surface of the channel against the sealing surface of the ring to thereby provide a fluid tight seal.

It is believed that the region of relatively increased wall thickness located below the outer wall groove assists in improving resistance to blow-off of the lid due to internal pressure within the container. In this regard, it will be appreciated that internal pressure within the container pushes the lid upwardly. The region of relatively increased wall thickness acts as a hoop. As the wall thickness of the hoop is relatively larger, the hoop provides a region of enhanced strength below the groove, which acts to enhance blow-off resistance. As, or if, internal pressure within the container continues to rise, the lid will buckle at the lower part of the channelshaped annular groove and the lid will then blow-off.

In preferred embodiments, the present invention also includes a region of relatively reduced wall thickness in the vicinity of the outer wall groove. This allows the outer wall groove to conform more closely to the bead, thereby enhancing the seal obtained when the lid is operatively positioned on the container.

The present invention also provides a lid for use in the container and lid 12700960 speci for response 09/02/06 -4assembly as described and claimed herein.

These and further features of the invention will be made apparent from the description of an embodiment thereof given below by way of example. In the description reference is made to the accompanying drawing but the specific features shown in the drawing should not be construed as limiting on the invention.

Brief description of the drawing Figure 1 depicts a cross-section through a part of a container and lid assembly with the lid installed on the container, showing those portions of the lid and container that interengage.

Detailed description of the embodiment As shown in the drawing, a container and lid assembly 10 comprises a container 12 having a cylindrical wall 14 with an upper edge 16 which is joined to an inwardly directed ring 18 by means ofa folded seam 20. The folded seam 20 is of typical construction and need not be described herein in any detail. The container 12 and the ring 18 are formed of sheet metal, termed "tinplate", and the ring 18 and folded seam 20 serve to strengthen and rigidify the upper edge 16 of the container 12.

The ring 18 is formed of a generally horizontally extending flange 22 which extends radially inwardly from the upper edge 16 of the container. A downwardly depending skirt 24 is integrally formed with the flange 22. The skirt 24 ends, at its lower edge, in a bead 26 which projects radially inwardly as shown in the drawing.

The bead 26 is formed by rolling the free end of the skirt 24 until the free end contacts the skirt 24. The bead 26 defines the radially innermost edge of the ring 18 and serves as a "wipe surface" as will be discussed in more detail below.

The lid 28 for the container is manufactured from a resilient plastics material and comprises a disk shaped body 30 which has a channel shaped groove 32 integrally formed therewith and extending around the radially outer periphery of the 12700960 speci for response 09/02/06 body 30. The channel 32 is relatively deep so that it extends below the lowermost edge of the bead 26 when the lid 28 is assembled onto the container, and includes an inner wall portion 32A, an outer wall portion 32B, and a lowermost bight portion 34. The lowermost portion 34 of the channel 32 serves as a "hinge" which allows the radially outer wall 36 of the channel 32 to flex as the lid 28 is pressed into the container in use. The radially outer surface 38 of the lid 28 serves to seal against the radially inner surface of the skirt 24 in order to provide a fluid tight seal where these two surfaces meet.

The formation of the channel 32 and the lowermost portion 34 enables the wall 36 to be compressed radially inwardly in use thereby causing the lid 28 to be in a compressed state. This compressed state assists the sealing action by the resilience of the channel 32 tending to bias the wall 36 towards the bead 26.

A groove 40 (the "outer wall groove") is defined in the radially outer surface of the wall 36 of the channel 32, the bead 26 locating in that groove 40 in order to positively locate the lid 28 and the ring 18 together. The groove 40 has a width indicated by dimension line W which is wider than the thickness of the bead 26 so that there is some vertical play therebetween, allowing relative movement between the bead 26 and the groove 40 when the lid 28 is operatively installed on the container. This allows positive location of the bead within the groove, even where there is paint build-up on the flange 22 and also allows the bead 26 to remain within the groove 40 even when the container 12 is dropped or otherwise mishandled.

Located below the groove 40 is a region 41 of relatively increased wall thickness which effectively acts as a hoop. This provides an area of enhanced hoop strength which resists inward deformation and assists in improving resistance to blow-off of the lid due to increased pressure within the container. The region of increased thickness 41 includes an upper outer surface 41A that slopes outwardly and downwardly from the groove 40, and a lower outer surface 41B that slopes inwardly and downwardly, and an inner thickened portion 41C, with the thickest 12700960 speci for response 09/02/06 -6part of the region 41 being defined at the apex between the two surfaces 41A and 41B.

As internal pressure builds up in the sealed container, inward deformation of the outer wall portion 32B of the channel, particularly in the hoop region of increased wall thickness 41, is minimal. Accordingly, rather than this outer wall portion 32B of the lid rotating inwardly and upwardly, which would serve to peel the seal open, the integrity of the seal in this region is maintained as the centre section of the lid tends to bulge out, with the seal area remaining substantially undeformed.

A lip 42 is provided on the radially outer edge of the lid 28. The lip 42 overlies the flange 22 and provides a feature to assist with the removal of the lid 28 from the container. A screwdriver, for example, could be inserted between the lip 42 and the flange 22 in order to prise the lid 28 free from the ring 18 by a combination of inward and then upward force and thereby allow the lid 28 to be removed from the container 12.

The arrangement provides a number of distinct advantages over many prior art containers of this type. First, the bead 26 provides a wipe surface against which brushes may be wiped and used. Since the bead 26 is located within the container any paint which is scraped or wiped off the brush during the wiping operation will drip downwards into the container 12 and will thus not be wasted and will not clog or deposit within or on the sealing surfaces of the ring 18. The skirt 24 provides a deep sealing surface against which the sealing surface 38 will press to form the fluid tight seal. A fluid tight seal will also be provided between the bead 26 and the groove 40 thereby ensuring that a satisfactory seal is maintained, even where some distortion of the container 12 has taken place. The resilience of the lid 28 and the degree of flexibility provided by the channel 32, in combination with the hoop strength provided by the area of increased wall thickness 41 beneath the groove, assists a proper seal being maintained to a surprising extent. Since the lid 28 is 12700960 speci for response 09/02/06 -7flexible, the removal of the lid 28 from the container and the re-insertion of the lid 28 into the container 12, can be performed without requiring special tools or without requiring undue force to be applied to the lid 28.

It will be appreciated that the construction of the container 12 and lid 28 of the invention is no more complex than prior art containers of this type and the container 12 can be manufactured and filled in conventional manufacturing facilities without requiring any significant retooling or adaptation of the manufacturing process.

Clearly, as mentioned above, the ring 18 need not be exactly the same form as described herein. The flange 22 may, for example, slope downwardly in a radially inward direction rather than upwardly as depicted in the drawing. Also, the skirt 24 need not be vertical and a radially inwardly sloping skirt will clearly also provide a satisfactory seal arrangement.

If desired, the features of the ring 18 can be formed integrally with the open end of the container 12. If such integral forming is performed it may be necessary to ensure that sufficient strength is provided to substitute for the strength currently provided by the folded seam 20. Depending upon the application of the container 12, this strength may not be required.

Throughout this specification, references to "upwardly" and "outwardly" should be construed as being relative to the normal orientation of the container and lid in use. Throughout this specification, references to "inwardly" and "outwardly" and "outer" should be construed as being relative to the longitudinal axis of the container in normal use.

Throughout this specification and the claims which follow, unless the context requires otherwise, the word "comprise", and or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated 12700960 speci for response 09/02/06 -8integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps.

The reference to any prior art in this specification is not, and should not be taken as, an acknowledgment or any form of suggestion that that prior art forms part of the common general knowledge in Australia.

Claims (26)

1. A container and lid assembly, the container including a generally cylindrical body having an open mouth, a generally annular flange extending radially inwardly from an upper edge of the container, a downwardly extending skirt depending from a radially inner edge of the flange and a bead formed on a lowermost edge of the skirt, a radially inner face of the skirt and/or the bead forming a sealing surface, the lid including a generally disc-shaped body, the lid having a channel-shaped annular groove formed therein, a radially outer surface of the channel-shaped annular groove defining a sealing surface adapted to seal with the sealing surface of the container, a radially outer surface of an outer wall of the channel-shaped annular groove defining an outer wall groove adapted to receive the bead when the lid is operatively installed on the container and wherein the outer wall of the channel-shaped annular groove has a region of increased wall thickness at least at an inner wall portion of the outer wall positioned below the outer wall groove, to increase the hoop strength of the outer wall in the region.

2. A container and lid assembly as claimed in claim 1 wherein the outer wall of the channel-shaped annular groove has a region of relatively reduced wall thickness in the vicinity of the outer wall groove.

3. A container and lid assembly as claimed in claim 1 or claim 2 wherein a lower part of the outer wall groove includes an outer surface that slopes outwardly and downwardly into the region of increased wall thickness.

4. A container and lid assembly as claimed in any one of the preceding claims wherein the region of increased wall thickness includes a lower edge that slopes downwardly and inwardly towards a lower part of the channel-shaped annular groove.

A container and lid assembly as claimed in any preceding claim wherein the region of increased wall thickness includes an inner wall portion which 12700960 speci for response 09/02/06 extends outwardly and downwardly from the region of the outer wall groove.

6. A container and lid assembly as claimed in any one of the preceding claims wherein the outer wall groove has an overhanging upper outermost edge.

7. A fluid container and lid as claimed in any one of the preceding claims, wherein said outer wall groove is dimensioned to be wider than the thickness of the bead to allow some play in locating of the bead within the outer wall groove.

8. A container and lid assembly as claimed in any one of the preceding claims wherein the lid is made from a resilient plastics material.

9. A container and lid assembly as claimed in any one of the preceding claims wherein the annular flange, the downwardly extending skirt and the bead are formed on a ring attached to the container.

A container and lid assembly as claimed in any one of the preceding claims wherein the lid has an outwardly extending lip-which overlies the flange when the lid is operatively installed on the container.

11. A container and lid as claimed in any one of the preceding claims wherein said bead is located radially inwardly of the skirt.

12. A container and lid as claimed in any one of the preceding claims wherein said skirt is vertical, substantially vertical, or near vertical.

13. A container and lid as claimed in any one of the preceding claims wherein said flange is one of the following: horizontal; sloped upwardly in a radially inward direction or sloped downwardly in a radially inward direction.

14. A container and lid as claimed in any one of the preceding claims wherein said container, said annular flange, said downwardly extending skirt and said bead are formed from sheet metal material.

A container and lid as claimed in claim 9, wherein said container and 12700960 speci for response 09/02/06 -Il- said ring are joined with leak-tightness to the upper edge of the container in a rolled and folded seam arrangement.

16. A container and lid as claimed in any one of the preceding claims wherein said bead is formed by rolling the free end of said skirt.

17. A lid for use in a container and lid assembly as claimed in any one of the preceding claims, said lid including a generally disc-shaped body, the lid having a channel-shaped annular groove formed therein, a radially outer surface of the channel-shaped annular groove defining a sealing surface adapted to seal with the sealing surface of the container, a radially outer surface of the channel-shaped annular groove defining an outer wall groove adapted to receive the bead when the lid is operatively installed on the container and wherein an outer wall of the channel-shaped annular groove has a region of increased wall thickness at least at an inner wall portion of the outer wall positioned below the outer wall groove, to increase the hoop strength of the outer wall in the region.

18. A lid as claimed in claim 17, wherein the outer wall of the channel- shaped annular groove has a region of relatively reduced wall thickness in the vicinity of the outer wall groove.

19. A lid as claimed in claim 17 or claim 18 wherein a lower part of the outer wall groove includes an outer surface that slopes outwardly and inwardly towards the region of relatively increased wall thickness.

A lid as claimed in any one of claims 17 to 19, wherein the region of increased wall thickness includes a lower edge that slopes downwardly and inwardly towards a lower part of the channel-shaped annular groove.

21. A lid as claimed in any one of claims 17 to 20, wherein the region of increased wall thickness includes an inner wall portion which extends outwardly and downwardly from the region of the outer wall groove.

22. A lid as claimed in any one of claims 17 to 21 wherein the outer wall 12700960 speci for response 09/02/06 -12- groove has an overhanging upper edge.

23. A lid as claimed in any one of the claims 17 to 22, wherein said groove is dimensioned to be wider than the thickness of the bead to allow some play in locating of the bead within the groove.

24. A lid as claimed in any one of claims 17 to 23 wherein the lid is made from a resilient plastics material.

A lid being substantially as herein described with reference to the accompanying drawing.

26. A container and lid assembly being substantially as herein described with reference to the accompanying drawing. DATED this 9 th day of February 2006 VISY INDUSTRIAL PLASTICS PTY LTD by DAVIES COLLISON CAVE Patent Attorneys for the applicant