GB2294446A

GB2294446A - Easy-open beverage container

Info

Publication number: GB2294446A
Application number: GB9521774A
Authority: GB
Inventors: David Elliot
Original assignee: Individual
Current assignee: Individual
Priority date: 1994-10-24
Filing date: 1995-10-24
Publication date: 1996-05-01
Anticipated expiration: 2015-10-24
Also published as: GB2294446B; GB9421392D0; GB9521774D0

Abstract

A container 1, such as a drinks can, comprises a surface 2 with an integral discrete area 4 bounded by a line of weakness 5, the discrete area having a recessed portion C and a projecting portion A, B with a curved edge 7, surface B of the projecting portion being a rising slope which receives pressure and surface A being a falling slope which transmits pressure to the line of weakness 5 producing a break at point 8 which progressively spreads around the line of weakness. The point of initial opening 8 may be part of the line of weakness or may be an aperture sealed by a gasket or plastisol closure to provide a weak zone from which the break can propagate. The pressure receiving surface B may be planar and at 45 degrees to the plane of the surface 2. Preferably the discrete area is housed in the top plate surface which is press-fitted or spun over the rim of the container side-wall and the line of weakness bounding the discrete area is created by scoring or kiss-cutting. There may be a break 6 in the line of weakness which acts as a hinge preventing the discrete area from fully detaching from the top plate surface. The central area of the top surface 2 may be raised to enhance the opening action (figures 5 - 7). The recessed portion C may comprise separate concertina areas (1, 2, 3 figure 9) to allow the entire discrete area to move horizontally on opening. The container may have an inwardly conical tapering top plate with an annular retroverted portion to provide protection against the sharp edge (figures 13 - 17). <IMAGE>

Description

TITLE Beverage Containers This invention relates to an improved construction of beverage container comprising a can for containing a beverage and wherein a top surface thereof is provided with a discrete defined area which may be broken away to gain access to the contents.

Although, as described herein, this invention is primarily directed to a can for containing a beverage, it is to be understood that the can with the means for effecting opening thereof could be used in connection with other constructions requiring a surface to have a portion thereof which may be broken away to provide an aperture. Thus, and essentially, this invention is more concerned with the construction of the discrete area which may be broken away from a larger area forming the container.

In prior art constructions relating to cans for containing beverage, a circular top surface thereof is provided with a discrete portion which may be torn away from the surrounding area. Such constructions are exemplified by "ring pull" means wherein a ring is grasped by a finger to tear away a portion of the top or by constructions using a ring which operates in a lever manner to depress a portion of the top downwardly into the container. A feature of these constructions is that the top of the can is integral with the portion to be broken away which is defined by kiss-cutting or otherwise weakening the material of the top around the discrete area. In another known construction, a separate pressdown pip is provided with the flange internal to the can which sealingly engages the inner surface of the top.A disadvantage of this latter construction is that the press down portion is a separate component and is required to be sealed, for example, using a gasket or the like against the inner surface of the top of the can.

One of the objects of this invention is to provide a means for generating an aperture in a top surface of a can which means is integral with the top surface and which can be broken away by downward depression into the interior of the can but without requiring a ring-pull or other separate projecting means of leverage.

According to this invention there is provided a container wherein a surface thereof includes a discrete area adapted to be broken-away from a surrounding area of said surface, the said discrete area being integral with said surface and bounded by a line of weakness whereby pressure force applied to the discrete area causes same to be at least partially torn away to leave an opening in said surface, characterised by the discrete area having a first projecting portion (A,B) asymmetrically positioned within a second recessed portion (C), said first projecting portion having a curvilinear edge defining a pressure receiving surface (B) formed by a rising slope to said edge and a force transmitting surface (A) defined by a falling slope from said edge to the bounding line of weakness, pressure applied to said surface (B) producing a break in the line of weakness through surface (A) which progressively spreads around the line of weakness.

Preferred features of this invention and a more full and complete description thereof and the manner of operation will now be described in conjunction with the accompanying drawings showing an embodiment by way of example only.

In the drawings: Figure 1 shows a top plan view of a beverage container can, Figure 2 shows a cross section generally on line II-II with profiles at three different spaced positions, Figure 3 is a fragmentary side view looking in the direction of the arrow III of Figure 1, Figure 4 shows the profile of the second recessed portion in the region of the periphery thereof, Figure 5 shows a similar but slightly modified construction, Figure 6 shows a section generally on V-V of Figure 5 with three profiles as in Figure 2, Figure 7 is a fragmentary side view generally looking in the direction of arrow VI of Figure 5, Figures 8 to 12 show a modified construction, Figures 13 and 14 show respectively fragmentary top sectional view and top plan view of a further preferred embodiment of can with a tapered top, Figure 15 shows a detail view of the convex annulus defining the point of fracture, Figure 16 shows a fragmentary detail view at the initial opening or fracture point, Figure 17 shows a plan view showing the closure in the process of being opened, and Figure 18 is a schematic detail view in perspective of the top area of the can.

Referring to Figures 1 to 4 of the drawings, and in particular to Figure 1, a standard form of beverage container can 1 has a substantially flat metal top surface 2 joined to the cylindrical can wall (not shown) by a spun-over rim 3. The top surface 2 embodies an off-centre discrete area 4 bounded by a line of weakness 5. The line of weakness 5 may be formed by kiss-cutting the metal and a small portion 6 is left unweakened or less weakened to form a hinge area such that the discrete area 4 will not completely separate from the top surface 2.

The discrete area 4 is comprised of a first projecting portion AB which is asymmetrically positioned within a second recessed portion C. The first projecting portion has a curvilinear edge 7 with a pressure receiving surface B defined by a rising slope from the recessed area C up to the edge 7. The projecting portion is further defined by a force transmitting surface A which extends from the edge 7 to an initial breaking point 8 provided on the line of weakness bounding the discrete area.

The recessed portion C which is defined by a negative curve facilitates lateral movement of the surface B and it is this portion C which allows the movement against gas pressure. The portion C also has a positive curve portion which facilitates simultaneously a downward movement of A against gas pressure.

To open the can, thumb pressure is applied to the surface B and by virtue of the arrangement of the surfaces C and A the force is transmitted into A and initially causes breakaway at point 8 which thereafter spreads around the line of weakness 5 defining the boundary. The hinge point 6 prevents the discrete area from detaching completely from the top of the can and falling into the interior.

A particular advantage of the construction according to this invention is that of reduced cost as there are no parts in the nature of a ring or other separate lever components on the top of the can and furthermore the top is left free to aid cleansing and to enable a user to drink directly from the side of the can.

Reduced cost of the construction is also achieved by the fact that the top is stamped in one piece.

The opening action is further significantly enhanced by raising the central area of the top surface 2 of the can in the region of the point 8 and such a modified construction is shown in Figures 5, 6 and 7 of the drawings, wherein like reference numerals have been used to indicate parts of like function. This construction is to be preferred. As shown in Figures 5 and 6, a raised area 9 is provided projecting above the plane of the top 2.

More specifically, operation of the opening action can be explained as follows: Gas pressure is minimised at the opening area due to the restricted size and shape and further in specific areas C to allow "give" in projections A and B.

Thumb plate B is pushed against small raised areas C and against lowered resistance (due to shape) of D, transmitting force into part A, which tends to lever down against C because of set angle into break point 8. Part A is so shaped (somewhat like a finger nail) as to be stronger than the slightly concave area of the break 8.

After breaking at the break point 8 the entire area can then be easily pushed in to hinge at 6. The lower part of B protrudes below the bottom level of the top of the can in order to allow an adequate surface area for the thumb. Part B may be pushed by the end of the thumb laterally or squeezed by the thumb with the fingers braced on the side of the can or squeezed by a finger with the thumb braced on the side of the can, or the palm of the hand against the side of the can.

The most crucial part of the present invention is area C since this allows the part B to be pushed enough to transmit the force in a lever action downwards through A to the break point 8, the gas pressure being minimised at points C due to very small surface area.

Also, if necessary, the opening part could be widened slightly.

It is a particular feature of this invention to provide a push-in discrete area which will operate against even relatively high internal can gas pressures and this is achieved by the particular arrangement of the projecting portion A,B operating in conjunction with the negative/positive curved area C. This is designed specifically to provide initial movement by applying a force obliquely to the plane of the top 2 in order to start the initial breaking action at point 8, whereupon gas pressure is relieved, thus allowing the breaking action to continue.

The angle at which A meets the indent at 8 is important and can be steeper than is shown in the drawing. When B is pushed more or less horizontally, A will only tend to angle down if it is set at a fairly sharp angle. The idea of the indent at the juncture of A and break point 8 was to further limit the gas pressure at the discrete area, but it may be made shallower or omitted altogether if necessary to help obtain a good operative relationship between the break point 8 and A.

Figures 8 to 12 illustrate a further and more specific embodiment which is designed to operate with greater internal can pressures. In this construction as shown the area C is modified by adopting a concertina form with separate areas 1,2 and 3. This arrangement allows the entire button to move horizontally and slightly upwards during the initial opening action. Fig 10 shows, in the upper view, the button before force is applied and, in the lower view, the button after opening with the area A now separated from the top surface.

Reference numerals have been omitted from these Figures for clarity, however the equivalence of parts is substantially the same as in Figures 1 to 6.

Figures 13 to 17 illustrate a further and more advanced form of construction. As shown, a can 30 has an inwardly conical tapering top 31 which is closed by a top plate 32 by means of a spun over liquid and gas-tight joint 33. The top plate 32 is dished inwardly and has an annular convex formation 34 which is provided with a retroverted portion 35 at which the line of weakness 36 is provided. The purpose of the retroverted portion 35 is to provide protection from the sharp edge when the top is pressed inwardly and severed along the line of weakness.

The line of weakness 36 is defined at one side 37 by a partial cut or score on the underside only whereby the part 37 acts as a hinge when the remainder of the line of weakness breaks. The portion A has a nose 38 where the break in the line of weakness around the peripheral area 36 commences.

In the region marked C the area has a negative curvature whereas in the region marked C1 this surrounding area has a positive curvature. The area of positive curvature C1 is the portion which contributes to the initial opening forces when thumb pressure is applied to the region B, for example as illustrated in Figure 17.

Figure 16 is a detail fragmentary view of the annular convex portion 34 and Figure 16 is a detail fragmentary view of the section at the initial opening point 38.

Figure 18 shows a detailed view of the opening portion of the can with reference to the areas A, B, C and C1. As may be seen, the area C is steeply concave whereas the bounding areas C1 have a positive curvature.

One advantage of the construction disclosed in Figures 15 to 18 is that the top of the can may be made of a smaller diameter due to the fact that no ring pull or other leverage means is present. The side of the can at the other end may therefore be tapered with a smaller top closure provided which obviates the need for reinforcement to withstand pressure in this area. In addition, substantially the whole of the surface area of the top is openable, thereby allowing the contents to be more freely withdrawn, either by drinking directly from the can or by pouring out the contents. Advantages where viscous liquids are contained in the can are obvious.

In a further modification which is not specifically illustrated, the line of weakness 36 is graduated along its length from the hinge area 37 where the weakness is least, to the point 38 where breaking away initiates where the weakness is most.

Another modification provides for the point of initial opening 8,38 to include an aperture or severed line which is sealed by a gasket or plastisol closure.

This reduces the initial opening forces by providing a weak zone from which the break along the line of weakness may propagate.

Claims

1. A container wherein a surface thereof includes a discrete area adapted to be broken-away from a surrounding area of said surface, the said discrete area being integral with said surface and bounded by a line of weakness whereby pressure force applied to the discrete area causes same to be at least partially broken or torn away to leave an opening in said surface, characterised by the discrete area having a first projecting portion (A,B) asymmetrically positioned within a second recessed portion (C), said first projecting portion having a curvilinear edge defining a pressure receiving surface (B) formed by a rising slope to said edge and a force transmitting surface (A) defined by a falling slope from said edge to the bounding line of weakness, pressure applied to said surface (B) producing a break in the line of weakness through surface (A) which progressively spreads around the line of weakness.

2. A container in accordance with Claim 1, wherein the line of weakness is defined by scoring or kiss-cutting.

3. A container in accordance with Claim 1 or 2 wherein the pressure receiving surface (B) is substantially planar and extends at an angle, typically 450, to the notional plane of the surface of the container.

4. A container in accordance with any preceding claim comprising a can with a top plate surface being the surface including the discrete area.

5. A container in accordance with Claim 4, wherein the top plate surface is connected with the open top of the can to form a closure.

6. A container in accordance with Claim 5, wherein the connection between the top plate surface and the can is formed by mechanical interlocking engagement, such as a press-fit or spun over rim, forming a liquid and gas tight seal.

7. A container in accordance with any one of Claims 4 to 6, wherein a press-formed upstanding annul us is provided on the top plate surface bounding the discrete area.

8. A container in accordance with Claim 7, wherein the inner edge of said annulus is retroverted and defines the line of weakness, the retroverted inner edge thus defining a smooth rounded edge when the discrete area is broken or torn away.

9. A container in accordance with any preceding claim, wherein the recessed portion (C) has concave curvature adjacent the juncture with pressure receiving surface (B) and a convex curvature at the juncture with the force transmitting surface (A).

10. A container in accordance with any preceding claim, wherein the force transmitting surface (A), in plan, has a tapered profile defining a nose terminating at the bounding line of weakness.

11. A container in accordance with any preceding claim wherein the discrete area is generally positioned centrally within a top surface of the container with the pressure receiving surface (B) lying generally at the centre of said discrete area.

12. A container in accordance with any preceding claim wherein the pressure receiving surface (B) has a generally elliptical planform with the plane of said surface lying at an acute angle relative to the plane of the top surface of the container.

13. A container in accordance with any preceding claim wherein the point at which the force transmitting surface (A) meets the bounding line of weakness forms a local arcuate zone having a radius of curvature greater than the radius of curvature of the bounding line of weakness to each side of said zone.

14. A container in accordance with any preceding claim, wherein the portion of the bounding line of weakness adjacent the second recessed portion (C) is less weak than the remaining portion of the bounding line of weakness whereby the discrete area may be progressively forced into the container but wherein the discrete area remains attached to the top surface of the container by virtue of bending about said portion.

15. A container, particularly of metal and for beverages, including a surface thereof having a discrete area being substantially as described herein and with particular reference to Figures 1 to 12 of the accompanying drawings or Figures 13 to 18 of the accompanying drawings.

16. A closure plate for a container including a discrete area constructed and arranged to function substantially as herein described or claimed.