US 3441167 A
Description (OCR text may contain errors)
April 29, 1969 A. E. BALoccA v 3,441,167
` EASY OPENING CONTAINER Filed oct. 20, 1967 INVENTOR. AL FRE!) EDWARD BAL Uff/4 ATTORNEY United States Patent O U.S. Cl. 220--53 14 Claims ABSTRACT OF THE DISCLOSURE A container is formed with a dispensing aperture which is surrounded by a raised bead having a sharp, downwardly facing inner edge. A plug type reclosure member is seated on the raised bead and has its bottom wall bonded to an internal sealing membrane which is secured to the interior of the container around the aperture. When the reclosure member is pulled upwardly, it pulls the sealing membrane against the sharp edge of the bead, thus causing severance and removal from the aperture of a segment of the sealing membrane which is larger than the aperture and which, upon replacement of the plug in the aperture as a reclosure, snaps beneath the bead edge to hold the plug in place on the container.
ln recent years, a great deal of effort has been expended in developing hermetically sealed cans -which are capable of withstanding substantial internal pressures but are nevertheless capable of being easily opened without the use of can openers or other special opening tools.
One line of development in this area has resulted in containers wherein a metal pull tab is secured to a scored removable section which is formed in a metal can end. When the pull tab is lifted, the score is ruptured and the removable section is torn from the end. This type of construction, -which is exemplified by the container disclosed in United States Letters Patent 3,225,957, granted Dec. 28, 1965, is somewhat objectionable in that it does not make provision for reclosure of the opening which is thus formed and in that the section which is removed is sharp-edged and somewhat hazardous if not properly disposed of.
Another avenue of approach has been to provide a container end having a precut aperture which is sealed by an internal sealing patch which is adhered to the inner surface of the end around the aperture. In such containers, the opening means takes the form of an external member which covers the aperture and is adhered to that portion of the sealing patch which is coextensive with the aperture so that when the opening means is pulled, the portion of the sealing patch coextensive with the aperture is torn against the edge of the end surrounding the aperture and is severed from the balance of the patch, which remains in the container. This type of container is typied by United States Letters Patent 3,302,818. United States Letters Patent 3,241,708 discloses a construction wherein the peripheral edge of the aperture is extended downwardly to provide a shanp cutting edge against which the sealing patch can be torn.
The present invention comprises a development of this latter type of container in that the aperture is surrounded by a raised bead which provides a seat for a plug type plastic reclosure member which is formed with an annular wall which engages the innermost corner of the downwardly facing, inclined raw edge of the bead. The outermost corner of the raw edge of the bead comprises a 3,441,167 Patented Apr. 29, 1969 ice sharp, knife-like edge which is preferably disposed above the sealing patch so that it does not prematurely rupture the sealing patch during manufacture or in the event the patch is pressed upwardly by the internal pressure in the container, and yet functions eiiciently as a rigid cutting edge when the reclosure member, which is bonded t0 the internal sealing patch, is lifted to pull the patch uplwardly against it. Because of the placement of this cutting edge, the severed portion of the patch projects laterally beyond the periphery of the plug and snaps beneath the bead when the plug is replaced in the aperture to serve as a reclosure, thus holding the plug in place in a snap-fit engagement. By virtue of this construction, an attractive, easily openable, reclosable container is provided which is capable of withstanding the substantial internal lpressure which are generated by such products as beer and carbonated beverages.
The raised bead serves to reenforce the end closure, rigidiiies and positions the cutting edge, adds appreciably to the finished appearance of the container, particularly after it has been opened, and functions as a shield to space the sharp edge of the aperture from the lips of the consumer in the event he should drink directly from the container.
An object of the invention is to provide an easily openable, reclosable container which incorporates some or all of the foregoing features and advantages.
Numerous other objects and advantages of the invention will be apparent as it is better understood from the following description, which, taken in connection with the accompanying drawings, discloses a preferred embodiment thereof.
Referring to the drawings:
FIG. 1 is a perspective view of a container embodying the principles of the instant invention;
FIG. 2 is an enlarged fragmentary section of a portion of the top end closure of the container of FIG. 1, the section being taken substantially along the line 2-2 in FIG. 1 but showing the end as it appears prior to being seamed onto the container body;
FIG. 3 is a perspective view of the upper portion of the container of FIG. 1 as it appears while it is being opened; and
FIG. 4 is a greatly enlarged fragmentary sectional detail of a portion of FIG. 2.
As a preferred and exemplary embodiment of the instant invention, the drawings disclose a can end closure 10 which is adapted to be secured to the upper end of a tubular can body 12 in any suitable manner, as by a conventional hermetic double seam 14. The body 12 may be of any suitable type and has its bottom end closed by means of a suitable bottom end closure 16.
The top end closure 10 is formed with a generally planar central panel 18 which is surrounded by a peripheral reenforcing groove 20 which at its outer edge merges into an upwardly extending countersink wall 22. The upper end portion of Wall 22 in turn merges into an out-wardly extending flange 23 which, after assembly of the body 12 and closure 10, becomes a portion of the double seam 14, as shown in broken lines in FIG. 2. The conventionally curled outer portion of the flange 23 is broken away in FIG. 2 because of spatial limitations.
The end closure 10, as well as the body 12, may be formed of suitable materials such as tin plate, coated steel, aluminum, etc. Other types of materials such as plastics, metal-plastic laminations, or other suitable laminated structures may also be utilized.
The end closure 10 is preferably formed with a pouring aperture 24 which is located near the periphery of the panel 18 and which, while herein shown as circular in outline, can be formed in many other suitable shapes such a keyhole, oval, radially elongated, etc. While the size of the aperture 24 is not critical, it is dependent to some extent on the type of product (not shown) usually a liquid, which is packed in the can. Thus, when pressurepacked or pressure-generating products such as beer or carbonated beverages are to be packed, the aperture 24 should be as small as is consonant with proper pouring in order to enable the closure to withstand the high internal pressures which are encountered with such products. When the interior of the can is not under pressure, as when non-carbonated beverages such as fruit juices are packed therein, the aperture 24 may be made appreciably larger.
In order to facilitate the ow of the product through the pouring aperture 24 when the latter is relatively small in size, as illustrated, a vent aperture 26, somewhat smaller in size than pouring aperture 24, is provided. This vent aperture 26 should be spaced an appreciable distance from the pouring aperture 24 in order that it may admit air to the interior of the can when the product is poured through the aperture 24. When the pouring aperture 24 is sufficiently large in size, the vent aperture 26 may be omitted.
The apertures 24, 26 are both sealed by means of an internal imperforate sealing membrane or patch 30 which is secured to the interior of the container in such manner as to prevent the product from reaching either of the apertures 24, 26. The patch 30 is preferably fabricated from Hat sheet stock or tape comprising a suitable thin, readily tearable, pressure resistant, impervious material such as aluminum or other metallic foil, or laminations of such metallic foils and other materials.
The sealing patch 30 of the illustrated embodiment of the invention comprises a piece of aluminum foil 31 of suitable thickness (2 mils is suitable for many products) and which is generally rectangular in shape, its outer edge being arcuate to conform to the shape of the panel 18. The upper surface of the foil 31 is `fully coated with a preapplied layer or lamination 32 of an adhesive which bonds it to the inner surface of the closure y around the apertures 24, 26 and thus seals them off from the interior of the can. If desired, the patch 30` may extend onto the groove to increase its resistance to creepage when subjected to internal pressures. The bottom surface of the foil 31, as well as its edges, may if desired, be protected by a thin layer or lamination of an inert organic resin (not shown) to protect the foil from the corrosive action which is inherent in some products packed in this type of container. It will be understood that all other surfaces of the container body and ends which are exposed to such products would be similarly protected by similar organic coatings (not shown) which would be preapplied to the inner surfaces of the body 12 and closures 10, 16. In such event, the layer 32 would adhere to such inner coating of the closure 10. If desired, suitable adhesion promoting coatings (not shown) and/or surface treatment, such as corona discharge, flame impingement, etc. (also not shown) could be utilized to enhance adhesion between the various elements of the closure.
The adhesive layer 32 preferably is formed of a synthetic thermoplastic resin or polymeric plastic which is adherently compatible with the other materials from which the closure 10 is made. Some exemplary adhesives are polyurethanes, polyvinyl plastisols, vinyl films, polyamides, and random copolymers of ethylene and acrylic acid such as are disclosed in U.S. Patent 3,239,370. By way of example, satisfactory results have been obtained by using a 2 mil layer of a random copolymer of ethylene and acrylic acid. However, thinner or thicker adhesive films can be used. Also, other types of adhesives, such as pressure-sensitive or thermosetting adhesives, may be utilized.
Each of the apertures 24, 26 is surrounded by a raised bead 34 which is formed in the panel 18, each bead 34 being generally arcuate in cross-section and terminating in an inner raw edge 38 which is preferably positioned at least slightly above the plane of the inside surface of the closure 10 and is inclined relative to sealing patch 30 so that its bottom, or outermost, corner 40 (see FIG. 4) forms a sharp, knife-like circular cutting edge which faces the sealing patch 30 in close proximity thereto. As seen best in FIG. 4, the raw edge 38 `and the inner surface of the bead 34 intersect at the corner 40 at substantially right angles to each other.
In order to make is possible to easily unseal the apertures 24, 26 and to reclose them after a portion of the product has been dispensed, a pull member 42 is seated on the raised beads 34. The pull member 42 is preferably injection molded from a suitable flexible thermoplastic resin such as polyethylene, polypropylene, polyurethane, phenoxy, a vinyl modied polyurethane, a random copolymer of ethylene and acrylic acid such as hereinbefore described, etc., and comprises a ilat web portion 43 and a pair of recessed plug elements 44, 46, which are shaped to fit into and plug the apertures 24, 26 respectively,
Each of the plug elements 44, 46 is formed with a flat bottom Wall 48, the bottom surface of which is substantially coplanar with the bottom surface of the closure panel 18 and is bonded to the sealing patch 30 by the adhesive layer 32, and a substantially cylindrical side wall 50 which lat its bottom is rounded off and engages against the innermost corner 52 of the raw edge 38 of the raised bead 34. Each plug element 44, 46 also includes a horizontal ange 54 which extends horizontally from the top of the friction Wall 50 and engages against the top of the raised bead 34 and thus controls the depth of insertion of the plug into its respective aperture.
The iianges 54 comprise portions of the web 43, as does the intermediate portion 56 which connects the friction plug elements 44, 46. The web 43 is shaped at one end to provide an integral ring-like handle element 60 which is readily engageable by a nger of the consumer to expedite opening of the container.
The sealing patch 30 is bonded to the underside of the panel 18 and the plug Walls 48 by the thermoplastic adhesive layer 32 in a bonding operation which involves the application of heat and pressure. This results in a ternporary softening of the adhesive 32 and causes it to be extruded upwardly around the plug elements 24, 26. If the adhesive layer 32 is thick enough and sufficient heat and pressure are applied, the extruded adhesive may contact, and even cover, the raw edges 38 of the raised beads 34. Normally, it is desirable to have at least a portion of the adhesive layer 32 interposed between the sharp corners 40 and the foil 31 to prevent premature, inadvertant rupture of the foil 31.
To open the can, the consumer need only hinge the handle 60 upwardly, insert one of his fingers into it, and pull upwardly on it, thus pulling the sealing patch 30 against the sharp cutting corner 40 which surrounds the venting aperture 26 and severing from the patch 30 a small disc 62 which remains secured to the plug element 46 and is pulled through the venting aperture 26 (see FIG. 3). Continued pulling on the handle similarly pulls the sealing patch 30 against the cutting corner 40 surrounding the main, pouring aperture 24, thus progressively severing from it a second, larger disc 64 and completing the opening operation. FIG. 3 shows the position of the parts as they appear during the severing of the disc 64. As indicated in FIG. 4, the severing action creating the disc 64 extends downwardly from the cutting corner 40 along a generally vertical annular line of severance indicated by the broken line 66. As a result, the stili" but exible outer, marginal edge portion 68 of each of the severed discs 62, 64 projects laterally beyond the annular plug wall 50 of its corresponding plug element.
After some of the contents of the container have been poured through the aperture 24, the friction plug elements 44, 46 may be pressed into their respective apertures to reclose the container, the curved inner portions of the beads 34 serving to guide the plugs easily into place. As the plug elements 44, 46 are thus seated, the projecting portions 68 of the discs 62, 64 snap past the corners 52 and engage beneath the raw edges 38 thus holding the plug elements 44, 46 in their apertures in a snap-lit engagement.
While the closure is shown as being flat in the drawings, it will be understood that it will be bulged upwardly to some extent when the interior of the can is under pressure. However, this does not normally affect the relationship and function of its parts. In the event that the pressure is suiciently great to cause the sealing patch 30 to tend to bulge slightly upwardly through the apertures 24, 26, it may be necessary to elevate the corners 40 relative to the plane of the inside surface of the closure in order to minimize the danger of having them prematurely initiate rupture of the foil 31. It has been found desirable to have the corners 40 positioned about .001-.002 inch above the adjacent inside surfaces of the closure 10. This precludes inadvertant premature rupture of the patch 30, and still provides for easy opening of the container. If this elevation is too great, it may be necessary for the user to manually stretch the patch 30 during the opening operation in order to bring it into severing contact with the cutting corners 40. At best, this would make it inordinately difficult to open the container, and at worst would cause tearing of the ring 60 or other failure of the opening device.
In situations where substantial internal pressures will be encountered in the filled and sealed container, it is desirable to emboss one or more shallow annular reenforcing corrugations or profile beads 70 into the portions of the patch 30 which span the apertures. These profile beads 70 which may be formed by suitably embossing the tools which apply the heat and pressure necessary to bond the patch 30 to the plug walls 48, permit the patch 30 to bulge upwardly to some extent into the apertures 24, 26 without splitting of the foil layer 31 in the bulged areas. With such profile beads 70, the ability of the patch 30 to withstand internal pressures without splitting is markedly increased.
It will be understood that it would be possible to embody the principles of construction of this invention in a container body rather than in a container end closure. It will also be understood that the term raw edge is used to designate an unhemmed edge, regardless of whether or not such edge is coated with a protective coating material.
It is thought that the invention and many of its attendant advantages will be understood from the foregoing description and it will be apparent that various changes may be made in the form, construction and arrangement of the parts without departing from the spirit and scope of the invention or sacricing all of the material advantages, the form hereinbefore described being merely a preferred embodiment thereof.
1. An easy opening container component comprising a panel portion having an aperture formed therein, a raised bead surrounding said aperture terminating in a downwardly facing raw edge, an internal sealing membrane bonded to the underside of said panel and sealing said aperture, and a pull member bonded to a portion of said sealing membrane through said aperture and adapted to be pulled upwardly to cut said membrane at the outer corner of said edge so that the severed portion snaps beneath said raw edge when said pull member is pressed down on to said panel to permit said member to serve as a reclosure.
2. The container component of claim wherein said downwardly facing raw edge is disposed above the level of the adjacent inner surface of said panel portion.
3. The container component of claim 15 wherein said raw edge is inclined upwardly with respect to said opening so that its bottom corner is closest to said sealing membrane and functions as a knife-like cutting edge when the latter is pulled upwardly against it.
4. The container component of claim 3 wherein said raw edge inclines upwardly and inwardly from said bottom corner so that the said bottom corner is spaced outwardly of the innermost corner of said raw edge.
5. The container component of claim 3 wherein said pull member includes a plug element which fits into said aperture within said raised bead.
6. The container component of claim 5 wherein said plug element includes a side wall which is surrounded by said raised bead and a bottom wall which is substantially coplanar with the adjacent inner surface of said panel portion and is bonded to said sealing membrane.
7. The container component of claim 6 wherein said membrane comprises a gas impermeable layer.
8. The container component of claim 7 wherein said gas impermeable layer is formed of a tearable metallic foil.
9. The container component of claim 8 wherein the portion of said tearable metallic foil which is bonded to said plug element is embossed to prevent premature rupture when it is bulged upwardly by internal pressure.
10. The container component of claim 1 wherein said pull member comprises an injection molded plastic piece which is formed with an integral pull handle element.
11. An easy opening container component, comprising a panel portion having an aperture formed therein, a raised bead surrounding said aperture and terminating in a downwardly facing raw edge, said raw edge being disposed above the level of the adjacent inner surface of said panel, a metallic foil sealing membrane bonded to the inner surface of said panel portion around said aperture by a layer of a thermoplastic adhesive, the raw edge of said raised bead being disposed above the level of said metallic foil sealing membrane and being inclined upwardly and inwardly and having its bottom, outermost corner spaced closest to said metallic foil membrane to provide a knifelike cutting edge, a molded plastic pull member comprising a plug element having a ange and having a bottom wall which is bonded to said metallic foil sealing membrane by said thermoplastic adhesive, said plug element having a sidewall which is spaced inwardly of said bottom corne-r of said raised bead raw edge so that when said pull member is pulled upwardly to move said sealing membrane into contact with said bottom corner to cause said corner to sever a portion of said sealing member along a line of severance which is spaced outwardly of the adjacent periphery of said plug element, the severed portion of said sealing membrane projects outwardly beyond said plug lement and is engageable in snap-fit engagement beneath a portion of said raised bead when said plug element is inserted into said aperture so that said flange contacts the upper surface of said raised bead to permit said pull member to function as a reclosure.
12. An easy opening container end closure, comprising a panel portion having an aperture formed therein, a raised bead surrounding said aperture and terminating in a downwardly facing sharp raw edge which is inclined upwardly and inwardly relative to said aperture, a sealing membrane comprising an impervious metallic foil layer bonded tothe inner surface of said panel portion around said aperture by a layer of an organic resin, at least a portion of said organic resin layer being interposed between said raw edge and said metallic foil layer to prevent inadvertent severing of said layer, and a molded plastic pull member including a plug element disposed in said aperture and bonded to said organic resin layer through said apertures, said pull element also including handle means so that when said handle means is pulled, said plug element pulls said sealing membrane against the said downwardly facing raw edge around said aperture to sever from said membrane the portion thereof which is coextensive with said aperture.
A 7 8 13. The end closure of claim 12, wherein said raw References Cited edges inc lude a sharp, knife-like bottom corner which UNITED STATES PATENTS severs said sealing membrane outwardly of the adjacent portions of said plug elements to provide laterally project- 3281024 10/1966 Henchert et al' Q -53 XR ing means bonded to said plug elements which are engage- 3302818 2/1967 Balocca et al' 22o- 53 able beneath said raw edges when said plug elements are 5 3341057 9/1967 Frankenberg 22o-53 XR inserted into said apertures to function as reclosures.
14. The component dened in claim 12 wherein said GEORGE T HALL Prlmary Examiner foil layer is embossed to prevent premature rupture when U.S. Cl. X.R.
itis bulged upwardly by internal pressure. 10 222-641; 220-44