Panel interlocking means for cartons

Information

  • Patent Grant
  • 6289651
  • Patent Number
    6,289,651
  • Date Filed
    Friday, October 8, 1999
    25 years ago
  • Date Issued
    Tuesday, September 18, 2001
    23 years ago
Abstract
Panel interlocking means secures together first and second panels in overlapping relationship. The first panel comprises a locking tab struck therefrom adjacent the free edge thereof The locking tab extends away from the free edge of the first panel and defines a first aperture in the first panel. The locking tab has a neck portion hinged at its base to the first panel and terminates in its shoulder portion. The second panel includes a second aperture struck therefrom adjacent the free edge thereof. The second aperture receives the locking tab such that when the panels are locked together, the free edge of the second panel is located along the locking tab between the base of the neck portion and the shoulder portion, and the locking tab is engaged with an edge of the first aperture.
Description




This invention relates to panel interlocking means for securing together a pair of panels, for example, adjacent overlapping panels of a paperboard carton. In some situations, these panels are provided by the opposite ends of a wrapper blank which are brought together in overlapping relationship and interlocked.




Locking tabs which are struck from one end of the carton wrapper and which are arranged to be driven through corresponding apertures defined by retaining tabs, struck from an opposite end of a wrapper are well known. However, in the present invention, the interlocking of panels is effected by causing a locking tab to be engaged through an aperture. In the present invention, locking tabs are directed away from the free end of their respective panel, such configurations are known, for example, U.S. Pat. No. 3,351,263 (Wood). This application shows a locking arrangement in which a first panel includes a locking tab which is directed away from free end of the first panel. A second panel includes a first aperture through which the tab is passed and then passed over a portion of the panel located beyond the aperture and is inserted through a second aperture in select combination.




A problem associated with known locking arrangements is that the forming of such locking arrangements is complicated and requires additional features, for example, additional retaining means or apertures. The more complicated arrangements also require precise registration of the two panels that are to be interlocked.




The present invention seeks to mitigate the problems outlined above by providing a simplified but secure locking arrangement.




One aspect of the present invention provides panel interlocking means for securing together a first and a second panel in overlapping relationship, the first panel comprising a locking tab struck from the first panel adjacent a free edge thereof and extending away from the free edge of the first panel. The locking tab has a neck portion hinged at a base thereof to the first panel and terminating in a shoulder portion and wherein the second panel includes an aperture struck from the second panel adjacent a free edge thereof and wherein the aperture is adapted to receive the locking tab such that when the panels are locked together the free edge of the second panel, outboard of the aperture, is located along the locking tab between the base of the neck portion and the shoulder portion.




According to an optional feature of this aspect of the invention the neck portion may include a transverse fold line so that the shoulder portion is hinged relative to the neck portion.




According to another optional feature of this aspect of the invention a locking edge may be formed between the underside of the shoulder portion and the neck portion. Preferably, the locking edge is adapted to interengage with a complementary edge of an aperture of the first panel which was created by the formation of the locking tab




Another aspect of the present invention provides panel interlocking means for securing together a first panel and a second panel in overlapping relationship, the first panel comprising a locking tab struck from the fit panel adjacent to the free edge thereof and extending away from the free edge of the first panel, the locking tab having a neck portion hinged at a base thereof to the first panel and terminating in a shoulder portion, and wherein the second panel includes an aperture struck from the second panel adjacent the free edge thereof, and wherein the aperture is adapted to receive the locking tab such that the locking tab overlaps part of the second panel between the aperture and the free edge, and wherein a locking edge of the locking tab is provided at each of the opposed side edges of the locking tab at the transition between the neck portion and the shoulder portion to interengage with complementary edges of an aperture created by formation of the locking tab to maintain the first panel and the second panel in a locked overlapped relationship.




According to an optional feature of this aspect of the invention, the neck portion may include a transverse fold line so that the shoulder portion is hinged relative to the neck portion adjacent the locking edges.




According to another optional feature of this aspect of the invention, the locking edges of and the complementary edges may be curvilinear.




Another aspect of the invention provides a method of securing together a first panel and a second panel in overlapping relationship, the first panel comprising a locking tab struck from the first panel adjacent a free edge thereof and extending away from the free edge of the first panel, the locking tab having a neck portion hinged at the base thereof to the first panel adjacent the free edge and terminating in a shoulder portion, and wherein the second panel includes an aperture struck from the second panel adjacent a free edge thereof, which method comprises the following steps: (i) folding the locking tab out of the plane of the first panel and towards the free edge thereof; (ii) bringing the first and second panels into overlapping relationship so that the aperture and locking tab are brought into registry; (iii) inserting the locking tab through the aperture; and (iv) folding the locking tab into overlapping relationship with the second panel between the aperture and free edge thereof towards its original position and inserting it through the aperture from which the locking tab was struck such that the locking tab is interengaged with an edge portion of the tab aperture such that the first and second panels are locked together in overlapping relationship. Preferably, the free edge of the second panel outboard of the aperture is located along the locking tab between the base of the neck portion and the shoulder portion.




Another aspect of the invention provides a carton blank incorporating panel interlocking means having a first panel and a second panel, the first panel comprising a locking tab struck therefrom including a neck portion and a shoulder portion, the neck portion being positioned adjacent to the free edge of the first panel and hinged to the first panel by a fold line at the base of the neck portion and wherein opposed side edges of the locking tab at the transition between the neck portion and shoulder portion are each shaped to define a locking edge extending from the tab to cooperate with an adjacent locking edge formed in the first panel and wherein a locking aperture is struck from the second panel spaced from its free edge to receive the locking tab.




According to an optional feature of this aspect of the invention, said neck portion may include a transverse fold line so that said shoulder portion is hinged relative to the neck portion.




According to another optional feature of this aspect of the invention, there may further comprise a locking edge formed between the underside of said shoulder portion and said neck portion, said locking edge being adapted to internegage with a complementary edge of an aperture of the first panel which was created by the formation of said locking tab. Preferably, said locking edges and said complementary edges are curvilinear.











An embodiment of the invention will now be described, by way of example only, in which:





FIG. 1

shows a pair of panels which are positioned opposite ends of a carton blank, in close proximity, one of which includes a locking tab and the other of which includes locking apertures; and





FIGS. 2

,


3


and


4


are perspective views of part of the panels illustrated in

FIG. 1

showing the various stages of interlocking the two panels.











Referring to the drawings, a pair of panels


10


,


12


respectively are adapted to be placed in an overlapping relationship and interlocked and are formed from paperboard or similar foldable sheet material. The panels


10


,


12


may, for example, be disposed at the opposite ends of one and the same carton blank which is to be formed into a carton sleeve in which panels


10


,


12


then provide bottom panels of die carton. The carton is used for packaging a plurality of articles, for example, cans. It is envisaged that the panel interlocking means for securing together a first and second panel can be incorporated into a variety of carton types, for example wraparound, basket or fully enclosed without departing from the scope of invention.




Locking tab


14


is struck from panel


10


and is hingeably coated thereto by fold line


16


with the locking tab extending away from the free edge. In this embodiment, the fold line


16


is substantially parallel to and spaced from the end edge


18


of panel


10


. The locking tab


14


comprises a neck portion


20


and a “shoulder” or main portion


22


. The neck portion


20


is hingeably connected to first panel


10


along fold line


16


. As shown in

FIG. 1

, a pair of oppositely disposed cut lines


24


,


26


define the side edges of the neck portion


20


and the main portion


22


is hingeably connected to neck portion


20


along a transverse fold line


28


which is substantially parallel to fold line


16


. Optionally, fold line


28


is separated by a cut line


30


to make folding the shoulder portion


22


easier.




The shoulder portion


22


is separated from panel


10


by a cut line


32


which in this embodiment is substantially “D shaped”: the cut line


32


can also define a pair of interlocking parts


34


,


36


positioned along the opposing side edges of shoulder portion


22


. Preferably, the cut lines


24


,


26


are curvilinear to define a pair of oppositely disposed an anchor tabs


38


,


40


connected to first panel


10


and positioned adjacent to side edges of neck portion


20


. Thus, at the intersection of cut lines


24


and


30


and cut lines


26


and


30


, a locking edge


42


,


44


which in this embodiment is substantially hook shaped is formed for interlocking parts


24


,


26


respectively.




As shown in

FIG. 1

, an aperture


46


which is preferably elongate in shape, is struck from panel


12


, being substantially parallel to the free edge


48


of second panel


12


and comprising a front edge


50


and a rear edge


52


, the front edge


50


being nearer to the free edge


48


of panel


12


. Preferably, the front edge


50


of aperture


46


is spaced from the free edge


48


of panel


12


by a distance d which corresponds approximately to the length of neck portion


20


(shown in FIG.


3


). In this embodiment, the free edge


48


is formed with an indentation


49


so that the distance is reduced to the correct dimensions outlined above. In this embodiment, there are two further locking tabs


60


and apertures


62


which are substantially identical to locking tabs


14


and aperture


46


and are not therefore described in any greater detail.




Turning to the construction of the panel interlocking means, illustrated in

FIGS. 2

to


4


, the blank requires a series of sequential folding operations. The folding process is not limited to that described below and can be altered according to the particular manufacturing requirements.




One method of locking together panels


10


and


12


is first fold the locking tab


14


about fold line


16


into a substantially face contacting overlapping relationship with portion of first panel


10


. The panels


10


and


12


are brought into an overlapping relationship with each other, and locking tab


14


can then be folded out of alignment with panel


10


and through aperture


46


, as illustrated in FIG.


2


. It will be appreciated by those skilled in the art that the locking tab may be an interference fit with the locking aperture. One advantage of the present invention is that the locking process does not require precise registration of the two panels


10


and


12


, because locking tab


14


is self locking in its own aperture.




The natural resilience of the paperboard material then allows the locking tab to automatically spring back in the direction F into its original position as shown in FIG.


3


. Optionally, guide means is used if manufacturing requirements or the carton design means that the locking tab


14


needs to be guided back to its original position. Optionally, the shoulder portion


22


of locking tab


14


is folded out of alignment with neck portion


20


along fold line


24


. In this embodiment, locking tab


14


is pushed in the direction G through the aperture


54


created by the formation of locking tab


14


such that the interlocking parts


34


,


36


and the anchor tab


38


,


40


may interengage, as shown in FIG.


4


.




Tension is applied to the panels in opposition to the locking direction, i.e. in a direction tending to move the panels apart. Thus, the butt engagement between the interlocking parts


34


,


36


and the anchoring tabs


38


,


40


maintain the locking tab


14


in its locked condition. Panels


10


,


12


remain interlocked because the front edge of aperture


46


is located along the locking tab


14


between the base of the neck portion and the shoulder portion


22


and, preferably, in butt engagement with fold line


16


of panel


10


.




Thus, the free edge of panel


12


, outboard of the aperture


48


is located along the locking tab between the base of the neck portion and the shoulder portion.




Further, or alternatively, the locking tab overlaps part of the second panel between said aperture and said free edge, and wherein a locking edge of the locking tab is provided at each of the opposed side edges of the locking tab at the transition between the neck portion and the shoulder portion to interengage with the free edge of the second panel outboard of said aperture located along the locking tab between the base of said neck portion and said shoulder portion.




The present invention and its preferred embodiment relates to a means of locking two adjacent panels in a wraparound carton and is shaped to provide satisfactory strength to maintain the panels in a locked position but with a degree of flexibility so that the load transferred to the panels is absorbed by the carrier. The shape of the blank minimises the amount of paperboard required. The carrier can be formed by hand or automatic machinery. It is anticipated that the invention can be applied to a variety of carriers not limited to those of the wraparound type.



Claims
  • 1. Panel interlocking means for securing together first and second panels in overlapping relationship, said first panel comprising a locking tab struck from said first panel adjacent a free edge thereof and extending away from the free edge of said first panel, the locking tab defining a first aperture in said first panel, the locking tab having a neck portion hinged at a base thereof to said first panel and terminating in a shoulder portion, wherein said second panel includes a second aperture struck from said second panel adjacent a free edge thereof, wherein said second aperture is adapted to receive the locking tab such that when the panels are locked together the free edge of said second panel, outboard of said second aperture, is located along the locking tab between the base of said neck portion and said shoulder portion, and wherein said locking tab comprises a locking edge adapted to engage with a complementary edge of said first aperture of the first panel.
  • 2. The panel interlocking means according to claim 1 wherein said neck portion includes a transverse fold line so that said shoulder portion is hinged relative to the neck portion.
  • 3. The panel interlocking means according to claim 1 wherein said locking edge is formed between the underside of said shoulder portion and said neck portion.
  • 4. Panel interlocking means for securing together a first panel and a second panel in overlapping relationship, said first panel comprising a locking tab struck from said first panel adjacent to a free edge thereof and extending away from the free edge of said first panel, said locking tab defining a first aperture in said first panel, said locking tab having a neck portion hinged at a base thereof to said first panel and terminating in a shoulder portion, wherein said second panel includes a second aperture struck from said second panel adjacent a free edge thereof, wherein said second aperture is adapted to receive the locking tab such that the free edge of said second panel is located along the locking tab between the base of said neck portion and said shoulder portion, and wherein said locking tab comprises a locking edge at each of opposed side edges of the locking tab at a transition between the neck portion and the shoulder portion to engage with complementary edges of said first aperture to maintain said first panel and said second panel in a locked overlapped relationship.
  • 5. The panel interlocking means according to claim 4 wherein said neck portion includes a transverse fold line so that said shoulder portion is hinged relative to the neck portion adjacent said locking edges.
  • 6. The panel interlocking means according to claim 4 wherein said locking edges and said complementary edges are curvilinear.
  • 7. A carton comprising first and second overlapping panels and panel interlocking means for securing said first and second panels together, said first panel comprising a locking tab struck from said first panel adjacent a free edge thereof and extending away from the free edge of said first panel, said locking tab defining a first aperture in said first panel, the locking tab having a neck portion hinged at a base thereof to said first panel and terminating in a shoulder portion, wherein said second panel includes a second aperture struck from said second panel adjacent a free edge thereof, wherein the locking tab is received in the second aperture and overlaps part of the second panel between said second aperture and said free edge of said second panel such that the free edge of said second panel is located along the locking tab between the base of said neck portion and said shoulder portion, and wherein said locking tab includes a locking edge disposed in engagement with a complementary edge of said first aperture.
  • 8. The carton according to claim 7 wherein said locking edge is formed at each of opposed side edges of said locking tab at a transition between said shoulder portion and said neck portion.
  • 9. A method of securing together a first panel and a second panel in overlapping relationship, said first panel comprising a locking tab struck from said first panel adjacent a free edge thereof and extending away from the free edge of said first panel, the locking tab defining a first aperture in said first panel, the locking tab having a neck portion hinged at a base thereof to said first panel and terminating in a shoulder portion, and wherein said second panel includes a second aperture struck from said second panel adjacent a free edge thereof, which method comprises the following steps:(i) folding the locking tab out of the plane of the first panel and towards said free edge of the first panel; (ii) bringing the first and second panels into overlapping relationship so that the second aperture and locking tab are brought into registry; (iii) inserting the locking tab through said second aperture; (iv) folding the locking tab towards said first aperture till the free edge of said second panel is located along the locking tab between the base of said neck portion and said shoulder portion; and (v) inserting the locking tab through said first aperture such that the locking tab is engaged at a locking edge thereof with a complementary edge of said first aperture whereby the first and second panels are locked together in overlapping relationship.
Priority Claims (2)
Number Date Country Kind
9702567 Feb 1997 GB
9704021 Feb 1997 GB
PCT Information
Filing Document Filing Date Country Kind 102e Date 371c Date
PCT/US98/02358 WO 00 10/8/1999 10/8/1999
Publishing Document Publishing Date Country Kind
WO98/34850 8/13/1998 WO A
US Referenced Citations (8)
Number Name Date Kind
3793928 Wooten Feb 1974
4004500 Wood Jan 1977
4062270 Culpepper Dec 1977
4429486 Bjornstad Feb 1984
5004147 Bienaime Apr 1991
5472138 Ingram Dec 1995
5595292 Bates Jan 1997
5611425 Holley, Jr. Mar 1997
Foreign Referenced Citations (1)
Number Date Country
321181 Nov 1997 TW