AU2001213601B2

AU2001213601B2 - Carton closure structure

Info

Publication number: AU2001213601B2
Application number: AU2001213601A
Authority: AU
Inventors: James R. Oliff
Original assignee: Meadwestvaco Packaging Systems LLC
Current assignee: WestRock Packaging Systems LLC
Priority date: 2000-10-10
Filing date: 2000-11-03
Publication date: 2006-08-03
Anticipated expiration: 2020-11-03
Also published as: WO2002030785A1; EP1326788B1; DK1326788T3; BR0017352A; ATE296239T1; JP4542310B2; EP1326788A1; ES2240196T3; AU1360101A; CA2464719A1; DE60020408D1; CA2464719C; JP2004510656A; BR0017352B1; MXPA03002942A; DE60020408T2; PT1326788E

Abstract

An end closure structure for a tubular structure has lines of joinder with closure flaps that are disposed to minimize the deformable area of an end wall by creating a tight structure that is less prone to blousing or bulging. The length of top (22) and bottom (26) panels is less than the length of side panels (24). The side panels terminate in weakened lines of joinder (55) that are arced toward adjoining side flaps (25). Almond-shaped transition panels (60) further facilitate a snug, secure end closure that is not easily deformed by bulging or blousing.

Description

CARTON CLOSURE STRUCTURE Field of the Invention The invention relates to cartons, and more particularly, to cartons having a closure structure that enhances carton integrity and appearance.

Background of the Invention It is important when forming enclosed packages of articles to have a package that is secure and not prone to unexpected opening and that does not present problems in handling. A problem with known end or side-loaded tubular type cartons is that the end structures become slack upon stacking and handling of the packages. This is particularly true when articles such as beverage cans are packaged in cartons. One solution is to provide beveled corners. EP 0 500 258 illustrates one example of a carton having beveled corners.

Modern beverage cans usually have top and bottom components that are smaller in diameter than the body of the can. This means that there is often substantial space between the corners of the end structure of a carton and the tops and bottoms of the cans.

In addition, the cans are typically designed to telescopically nest when they are stacked one upon another. Thus, when packages of cans are stacked upon one another the cans tend to nest as much as they are able. This action decreases the overall height of a carton thereby causing the end walls to bow outwardly. This outward bowing, or bulging, is also known as blousing.

Blousing creates problems because it can place undue stress upon the flaps forming the end walls of cartons thereby causing glued panels to fail. A blousing type of carton deformation also creates a protrusion, which can cause snags or otherwise interfere with handling.

(R:\LIBLL]18673speci doc KEH Object of the Invention It is an object of the present invention to overcome or ameliorate some of the disadvantages of the prior art, or at least to provide a useful alternative.

Summary of the Invention One aspect of the invention preferably provides a carton comprising opposing top and bottom panels and opposing side panels adjoining one another forming a tubular structure; a side flap foldably adjoining each end edge of each of said side panels along respective first weakened lines ofjoinder, major flaps foldably adjoining said top panel along respective second weakened lines ofjoinder and minor flaps adjoining said bottom io panel along respective third weakened lines ofjoinder, wherein the first weakened lines ofjoinder each extend entirely along the adjacent end edge of the respective side panel and arc towards said side flaps and wherein a length of at least one of said top and bottom panels is less than a distance between apexes of arcs of said side panels.

According to an optional feature of this aspect of the invention, the lengths of Is both the top panel and the bottom panel may be lengthwise less than the distance between apexes of arcs of the side panels.

According to another optional feature of this aspect of the invention, the top panel and the bottom panel may be of substantially equal length.

According to yet another optional feature of this aspect of the invention there may further comprise inwardly-inclined transition panels at respective ends of the side panels each formed by the first weakened line ofjoinder and a fourth weakened line of joinder positioned inwardly of the notional comer of the carton thereby to tighten the carton around the articles.

Preferably the fourth weakened line of joinder is arcuate to define a transition panel of an ellipsoidal shape.

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3 (Ni SIn one class of embodiments, there is provided a handle structure, wherein the fourth weakened line ofjoinder is placed across a panel forming the handle structure.

(Ni According to a still further optional feature of this aspect of the invention, the or each side panel may be separated from its adjacent side flap by the transition panel(s).

NsO A second aspect of the invention preferably provides a blank for forming a carton, the blank comprising a first panel for forming one of a top or bottom panel in the erected carton foldably adjoining a second panel for forming one side panel in the erected carton foldably adjoining a third panel forming the other of said top or bottom panel in the erected carton foldably adjoining a fourth panel for forming another side panel in the erected carton, a side flap foldably adjoining each end edge of each of said second and fourth panels along respective first weakened lines of joinder, major flaps foldably adjoining said first or third panel that serves as the top panel in the erected carton along respective second weakened lines ofjoinder, minor flaps adjoining said first of third panel that serves as the bottom panel in the erected carton along respective third weakened lines of joinder wherein the first weakened lines of joinder each extend entirely along the adjacent end edge of the respective side panel and arc towards said side flaps, and wherein a length of at least one of said first and third panels is lengthwise less than a distance between apexes of arcs of said second and fourth panels.

Preferably the lengths of both the top first panel and the third panel are lengthwise less than the distance between apexes of arcs of the second and fourth panels.

According to an optional feature of this aspect of the invention, the first panel and said third panel are of substantially equal length.

[R:\LIBLLI I 8673spcci.doc: KEH According to another optional feature of this aspect of the invention, there may further comprise inwardly-inclined transition panels at respective ends of the second and fourth panels each formed by the first weakened line of joinder and a fourth weakened line ofjoinder positioned inwardly of the notional corner of the carton thereby to tighten the carton around the articles in a set up carton.

Preferably, the fourth weakened line ofjoinder is arcuate to define a transition panel of an ellipsoidal shape. In one class of embodiments, there is provided a handle structure, wherein the fourth weakened line ofjoinder is placed across a panel forming the handle structure.

According to yet another optional feature of this aspect of the invention, the or each second and fourth panel is separated from its adjacent side flap by the transition panel.

Beneficially, almond-shaped transition panels further facilitate a snug, secure end closure that is not easily deformed by bulging or blousing.

Brief Description of the Drawings Exemplary embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings in which: FIGURE 1 is an isometric illustration of a carton having closure structure in accordance with the teachings of a preferred embodiment of the invention; FIGURE 2 is a plan view of a blank for forming the carton of Figure 1; and [R:\LIBLL]18673spci.docKEH FIGURE 3 is an elevational view of the carton of Figure 1 from an end thereof.

Throughout the drawings, same reference numerals are used to denote the same or like features of the invention.

Detailed Description of the Preferred Embodiments Reference may generally be made simultaneously to Figure 1 and Figure 2 throughout the explanation of the invention that follows. A carton 10 having closure structure in accordance with the teachings of the preferred embodiment of the invention is shown in Figure 1. A blank 12 suitable for forming the carton 10 is shown in Figure 2. A tubular structure, shown in Figure 1, is formed from panels, which for convenience of io reference, are referred to as top 22, a first side wall 24, bottom 26, and second side wall 20/28 panels hingedly connected together in series.

The designation of orientation of these panels relates to the orientation of articles such as cans C that are packaged in the articles which is non-limiting. As shown in Figure 1, the upright orientation of a can C corresponds to the designation of the panels is 22 and 26 as top and bottom panels, respectively, and the designation of panels 24 and bifurcated panel 20/28 as side panels. For convenience of explaining the blank 12, the panels that assume top and bottom panel disposition in the erected carton 10 are designated 22 and 26 and may be considered first and third panels in the blank. The endmost side panel [R:\LIBLLJ 18673speci.doc KEH WO 02/30785 PCT/USOO/30369 6 is shown in bifurcated form 20/28 but does not necessarily have to be formed in that fashion to practice the teaching of the invention. For convenience of reference, the first side panel 24 in the blank may be considered the second panel and the outermost side panel may be considered the fourth panel.

The orientation of each one of the pair of side panels with respect to one another and each one of the pair of top and bottom panels with respect to one another is inconsequential in the operation and teachings of the invention. For example, the top panel 22 may be used as the bottom panel 26 without departing from the teachings of the invention.

A plurality of flaps and gusset structures form end closure for the tubular structure. In this embodiment, side flaps 25, 21/29 are adjoined to respective ends of the side panels 24, 20/28 along scored, perforated or otherwise weakened lines of joinder 55. For convenience of reference, these are referred to as first weakened lines ofjoinder. All of the weakened lines of joinder described herein may be scored, perforated or otherwise weakened. Major flaps 23 are adjoined to the top (or first) panel along second weakened lines ofjoinder 45. Minor flaps 27 are adjoined to the bottom (or third) panel along third weakened lines Preferably, the first weakened lines of joinder 55 are arcuate, toward the side flaps 21/29. In the erected carton, the arcuate lines ofjoinder 55 have the effect of making the carton 10 widthwise more narrow at the ends (as shown in Figure 3).

In the preferred embodiment, the length L2 or L3 (that is, the distance between the second weakened lines ofjoinder 35 or third weakened lines ofjoinder 45) of at least one of the top and bottom panels 26, 22 is less than the length LI (that is, the distance between the apexes of the arcuate first weakened lines of joinder 55 so as to provide a tighter carton closure structure that is less prone to deformation by so-called blousing.

This is because the lengths L2, L3 of the top 22 and bottom 26 panels are less than the distance L between the apexes of the side walls 24, 20/28, so that the fold lines 45, WO 02/30785 PCT/U S0/30369 7 of the major 23 and minor 27 flaps, respectively, lie closer to or are even coincident with the chimes of cans C or similar articles that are packaged. This enables the package to be more tightly formed initially with less free or unencumbered major and minor flap area subject to the blousing effect. Accordingly, the side flaps 25, 21/29 are able to rest against the cans while the major and minor flaps 23, 27 fit snugly against the top and bottom portions of the cans.

In one class of embodiments, the carton end closure is made even more snug fitting with respect to the articles held within the carton through placement of a transition panel 50, 60 intermediate the side panels 24, 20/28 and the end walls of the carton.

Each transition panel 50, 60 is formed from a first weakened line ofjoinder 55 and a fourth weakened line ofjoinder 58. Preferably, the two lines are outwardly arcuate with respect to the transition panels 50, 60, whereby the fourth weakened line ofjoinder 58 is arced toward the opposite end of the respective side panel. This enables the end structures to adhere even more closely to the packaged articles (such as cans In the preferred embodiment, the arcuate weakened lines 55, 58 define an elipse, whereby transition panels/gussets have ends that intersect at the corners of the carton. Thus, transition panels provide a smooth transition from the side panels to a more narrow end wall and structure, shown in more detail in Figure 3.

The curvature of the lines ofjoinder 55, 58 forming the transition panel (or gusset) also adds to the vertical rigidity of the erected carton. This rigidity is useful in providing support for adhering the various flaps to one another upon carton end closure. In the preferred embodiment, the apex of each first weakened line ofjoinder 55 is disposed to coincide with the body of a comer article, at the end of a carton. Further, the apex of the fourth weakened line ofjoinder 58 may be disposed to coincide with the body of the comer article at its tangent with the side panel, so that at least part of the transition panel will abut a portion of the side of the article C.

In those embodiments with handle structure H, including a handle strap shown in Figure 2, the fourth weakened line ofjoinder 58 is adapted to be positioned across, or through, the strap.

WO 02/30785 PCT/USOO/30369 8 It will be recognised that as used herein, directional references such as "top", "base", "end", "side", "major" and "minor" do not limit the respective panels to such orientation, but merely serve to distinguish these panels from one another. Any reference to hinged connection or lines of joinder should not be construed as necessarily referring to a single fold line only: indeed, it is envisaged that hinged connection can be formed from one or more of one of the following, a score line, a frangible line or a fold line, without departing from the scope of invention.

It should be understood that various changes may be made within the scope of the present invention, for example, the size and shape of the transition panels and/or lines of joinder may be adjusted to acconmmodate articles of differing size or shape, or alternative top and base closure structures may be used. The carton may accommodate more than one article in different arrays.

Claims

1. A carton comprising opposing top and bottom panels and opposing side panels adjoining one another forming a tubular structure; a side flap foldably adjoining each end edge of each of said side panels along respective first weakened lines ofjoinder, major flaps foldably adjoining said top panel along respective second weakened lines of joinder and minor flaps adjoining said bottom panel along respective third weakened lines of joinder, wherein the first weakened lines of joinder each extend entirely along the adjacent end edge of the respective side panel and arc towards said side flaps and wherein a length of at least one of said top and bottom panels is less than a distance between apexes of arcs of said side panels.

2. The carton of claim 1, wherein the lengths of both said top panel and said bottom panel are lengthwise less than said distance between apexes of arcs of said side panels.

3. The carton of claim 1 or claim 2, wherein said top panel and said Is bottom panel are of substantially equal length.

4. The carton as claimed in any one of claims 1 to 3, further comprising inwardly-inclined transition panels at respective ends of said side panels each formed by said first weakened line of joinder and a fourth weakened line of joinder positioned inwardly of the notional corner of the carton thereby to tighten the carton around the articles.

The carton as claimed in claim 4, wherein the fourth weakened line of joinder is arcuate to define a transition panel of an ellipsoidal shape.

6. The carton as claimed in claim 4 or claim 5, having a handle structure, wherein the fourth weakened line ofjoinder is placed across a panel forming the handle structure.

7. The carton as claimed in any one of claims 4 to 6, wherein the or each side panel is separated from its adjacent side flap by said transition panel(s).

8. A blank for forming a carton, the blank comprising a first panel for forming one of a top or bottom panel in the erected carton foldably adjoining a second panel for forming one side panel in the erected carton foldably adjoining a third panel forming the other of said top or bottom panel in the erected carton foldably adjoining a fourth panel for forming another side panel in the erected carton, a side flap foldably adjoining each end edge of each of said second and fourth panels along respective first weakened lines of joinder, major flaps foldably adjoining said first or third panel that [R:\LIBLLI8673spcci.doc:KEH serves as the top panel in the erected carton along respective second weakened lines of joinder, minor flaps adjoining said first of third panel that serves as the bottom panel in the erected carton along respective third weakened lines of joinder wherein the first weakened lines of joinder each extend entirely along the adjacent end edge of the respective side panel and arc towards said side flaps, and wherein a length of at least one of said first and third panels is lengthwise less than a distance between apexes of arcs of said second and fourth panels.

9. The blank of claim 8, wherein the lengths of both said top first panel and said third panel arc lengthwise less than said distance between apexes of arcs of said second and fourth panels.

The blank of claim 8 or claim 9, wherein said first panel and said third panel are of substantially equal length.

11. The blank as claimed in any one of claims 8 to 10, further comprising inwardly-inclined transition panels at respective ends of said second and fourth panels each formed by said first weakened line ofjoinder and a fourth weakened line ofjoinder positioned inwardly of the notional corner of the carton thereby to tighten the carton around the articles in a set up carton.

12. The blank as claimed in claim 11, wherein the fourth weakened line of joinder is arcuate to define a transition panel of an ellipsoidal shape.

13. The blank as claimed in claim 11 or claim 12, having a handle structure, wherein the fourth fold line is placed across a panel forming the handle structure.

14. The blank as claimed in any one of claims 11 to 13, wherein the or each second and fourth panel is separated from its adjacent side flap by said transition panel.

A carton, substantially as herein described with reference to Figures 1 to 3.

16. A blank for forming a carton, substantially as herein described with reference to Figures 1 to 3. Dated 29 June, 2006 MeadWestvaco Packaging Systems, LLC Patent Attorneys for the Applicant/Nominated Person SPRUSON FERGUSON I R:\LIBLL I 8673speci.doc:KEH