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Title:
LOCKING ARRANGEMENT, CARTON, BLANK AND METHOD
Document Type and Number:
WIPO Patent Application WO/2014/093185
Kind Code:
A1
Abstract:
A locking arrangement secures together first and second panels. The arrangement includes locking tabs (54, 56, 58) projecting from an end edge (64) of the first panel (12) and locking slits (50a, 50b, 50c) in the second panel (28). Each locking slit is provided for receiving a respective one of the locking tabs. The locking tabs and the locking slits are engageable by relative sliding movement with each other. At least one of the locking tabs and locking slits is configured to secure the first and second panels in a first overlapping position while at least another one of the locking tabs and locking slits is configured to secure the first and second panels in a second overlapping position.

Inventors:
BATES, Aaron, L (16820 Jaydee Court, Moseley, Virginia, 23120, US)
MILLER, Bobby, L, Jr (3442 Greystone Street, Smyrna, Georgia, 30068, US)
Application Number:
US2013/073768
Publication Date:
June 19, 2014
Filing Date:
December 08, 2013
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
MEADWESTVACO PACKAGING SYSTEMS, LLC (501 South 5th Street, Richmond, Virginia, 23219-0501, US)
International Classes:
B65D71/14; B65D5/00; B65D71/16
Domestic Patent References:
WO1995035241A11995-12-28
Foreign References:
GB1219350A1971-01-13
FR2418158A11979-09-21
EP0447124A21991-09-18
JPH057656U1993-02-02
Other References:
None
Attorney, Agent or Firm:
SUZUKI, Tsugihiko et al. (501 South 5th Street, Richmond, Virginia, 23219-0501, US)
Download PDF:
Claims:
CLAIMS

1 . A locking arrangement for securing together a pair of panels, the arrangement comprising locking tabs projecting from an end edge of a first panel of the pair of panels and locking slits provided adjacent an end edge of a second panel of the pair of panels, wherein the locking slits are provided for receiving the locking tabs respectively, the locking tabs and the locking slits being engageable by relative sliding movement therebetween, wherein at least a first one of the locking tabs and locking slits is configured to secure the first and second panels in a first position in which the first and second panels overlap at a first degree of overlap, and wherein at least a second one of the locking tabs and locking slits is configured to secure the first and second panels in a second position in which the first and second panels overlap at a second degree of overlap.

2. A locking arrangement according to claim 1 wherein the second degree of overlap is greater than the first degree of overlap.

3. A locking arrangement according to claim 1 wherein the at least a first one of the locking tabs and locking slits comprises at least one of the locking tabs, and wherein the at least one of the locking tabs comprises an engaging edge spaced from the end edge of the first panel by a first distance.

4. A locking arrangement according to claim 3 wherein the at least a second one of the locking tabs and locking slits comprises at least another one of the locking tabs, and wherein the at least another one of the locking tabs comprises an engaging edge spaced from the end edge of the first panel by a second distance, the second distance being greater than the first distance.

5. A locking arrangement according to either of claims 3 or 4 wherein the engaging edge is a trailing edge of the locking tab.

6. A locking arrangement according to claim 1 wherein the at least a first one of the locking tabs and locking slits comprises at least one of the locking slits, and the at least one of the locking slits is spaced apart from the end edge of the second panel by a first distance.

7. A locking arrangement according to claim 6 wherein the at least a second one of the locking tabs and locking slits comprises at least another one of the locking slits, and the at least another one of the locking slits is spaced apart from the end edge of the second panel by a second distance, the second distance being greater than the first distance.

8. A locking arrangement according to claim 1 wherein the at least a first one of the locking tabs and locking slits comprises at least one of the locking slits, the at least one of the locking slits defines an abutment edge spaced from the end edge of the second panel by a first distance.

9. A locking arrangement according to claim 8 wherein the at least a second one of the locking tabs and locking slits comprises at least another one of the locking slits, the at least another one of the locking slits defines an abutment edge spaced from the free end edge of the second panel by a second distance, the second distance being greater than the first distance.

10. A locking arrangement according to any one of claims 1 to 9 wherein the locking tabs are each coupled to the first panel by a fold line.

1 1 . A locking arrangement according to claim 1 wherein the at least a first one of the locking tabs and locking slits comprises at least one of the locking tabs, the at least one of the locking tabs is coupled to the end edge of the first panel by at least one first fold line, the at least a second one of the locking tabs and locking slits comprises at least another one of the locking tabs, and the at least another one of the locking tabs is coupled to the end edge of the first panel by at least one second fold line, the at least one first fold line being offset from the at least one second fold line.

12. A locking arrangement according to claim 1 wherein the at least a first one of the locking tabs and locking slits comprises at least one of the locking tabs, the at least one of the locking tabs projects from the end edge of the first panel by a first dimension.

13. A locking arrangement according to claim 12 wherein the at least a second one of the locking tabs and locking slits comprises at least another one of the locking tabs, the at least another one of the locking tabs projects from the end edge of the first panel by a second dimension, the second dimension being greater than the first dimension.

14. A locking arrangement according to claim 1 wherein at least one of the locking tabs shares a common outline with at least another one of the locking tab.

15. A locking arrangement according to claim 1 wherein the locking tabs are arranged in first and second groups, wherein each of the locking tabs in the first group sharing a common outline with at least one adjacent locking tab in the first group, wherein each of the locking tabs in the second group sharing a common outline with at least one adjacent locking tab in the second group, and wherein the locking tabs in the first group are spaced apart from the locking tabs in the second group.

16. A locking arrangement according to claim 15 wherein one of the locking tabs in the first group is spaced apart from one of the locking tabs in the second group.

17. A locking arrangement according to claim 15 or 16 wherein the spacing between a locking tab in the first group and an adjacent locking tab in the second group is greater than the spacing between a pair of adjacent locking tabs in either of the first and second groups.

18. A locking arrangement according to any one of claims 14 to 17 wherein an aperture is defined between the locking tabs which share the common outline, the aperture being struck in part from the first panel and defining in part a recess along the end edge of the first panel.

19. A blank for forming a carton, the blank comprising a first panel, a second panel and a

locking arrangement for securing together the first and second panels, the arrangement comprising locking tabs projecting from an end edge of the first panel and locking slits provided adjacent an end edge of the second panel, wherein the locking slits are provided for receiving the locking tabs respectively, the locking tabs and the locking slits being engageable by relative sliding movement therebetween, wherein at least a first one of the locking tabs and locking slits is configured to secure the first and second panels in a first position in which the first and second panels overlap at a first degree of overlap, and wherein at least a second one of the locking tabs and locking slits is configured to secure the first and second panels in a second position in which the first and second panels overlap at a second degree of overlap.

20. A locking arrangement for securing together a pair of panels, the arrangement comprising at least one first locking tab projecting from an end edge of a first panel of the pair of panels, at least one second locking tab projecting from the end edge of the first panel, at least one first locking slit in a second panel of the pair of panels for receiving the at least one first locking tab and at least one second locking slit in the second panel for receiving the at least one second locking tab, wherein the at least one first locking tab and the at least one first locking slit are configured to secure the first and second panels in a first overlapping position and at least one second locking tab and at least one second locking slit are configured to secure the first and second panels in a second overlapping position.

21 . A blank for forming a carton for packaging one or more articles, the blank comprising a plurality of panels, wherein a first one of the plurality of panels comprises locking tabs projecting from an end edge of the first panel, and a second one of the plurality of panels comprises locking slits in the second panel, wherein each locking slit is provided for receiving a respective one of the locking tabs, the locking tabs and the locking slits being engageable by relative sliding movement therebetween, wherein at least one of the locking tabs shares a common outline or weakened line of severance with at least an adjacent one of the locking tabs.

22. A blank according to claim 21 wherein a portion of the at least one of the locking tabs defined by the common outline or weakened line of severance is complementary in shape to a portion of the at least an adjacent one of the locking tabs.

Description:
LOCKING ARRANGEMENT, CARTON, BLANK AND METHOD

CROSS REFERENCE TO RELATED APPLICATIONS This application claims the benefit of US Provisional Patent Application No. 61 /735,176 filed December 10, 2012, which is incorporated herein by reference in its entirety.

FIELD OF THE INVENTION

The present invention relates to a locking arrangement for a locking two panels of a carton together to a carton and a blank and a method of securing a carton blank about a product, more specifically, but not exclusively to a locking arrangement having multiple locking positions.

BACKGROUND OF THE INVENTION

In the field of packaging it is often required to provide consumers with a package comprising multiple primary product containers, such multi-packs are desirable for shipping and distribution and for display of promotional information. For cost and environmental considerations, such cartons or carriers need to be formed from as little material as possible and cause as little wastage in the materials from which they are formed as possible. Another consideration is the strength of the packaging and its suitability for holding and transporting large weights of articles.

It is desirable to lock a pair of panels forming a package about the primary product containers; in particular it is desirable to ensure a tight fit of the carton, such as but not limited to a wraparound style carton, about the primary product container or containers. SUMMARY OF INVENTION

The present invention seeks to overcome or at least mitigate the problems of the prior art.

According to a first aspect of the present invention there is provided a locking arrangement for securing together a pair of panels, the arrangement comprising locking tabs projecting from an end edge of a first panel of the pair of panels and locking slits provided adjacent an end edge of the second panel of the pair of panels, wherein a locking slit is provided for receiving each of the respective locking tabs, the locking tabs and the locking slits being engageable by relative sliding movement therebetween, wherein at least one of the locking tabs or locking slits is configured to secure the pair of panels in a first overlapping position and at least one of the other the locking tabs or locking slits is configured to secure the pair of panels in a second overlapping position. Optionally, the locking arrangement comprises at least one further locking tab or locking slit configured to secure the pair of panels in at least one further position having another degree of overlap.

Optionally, the second degree of overlap when the first and second panels are disposed in the second position is greater than the first degree of overlap when the first and second panels are disposed in the first position.

Optionally, at least one of locking tabs shares a common outline with at least one adjacent locking tab.

Optionally, the locking arrangement comprises a first group of locking tabs.

Preferably, each of the locking tabs in the first group sharing a common outline with at least one adjacent locking tab in the first group.

Optionally, the locking arrangement comprises a second group of locking tabs.

Preferably, each of the locking tabs in the second group sharing a common outline with at least one adjacent locking tab in the second group.

Optionally, the locking tabs in the first group of locking tabs are spaced apart from the locking tabs in the second group of locking tabs.

Alternatively, one of the locking tabs in the first group of locking tabs is spaced apart from one of the locking tabs in the second group of locking tabs.

Optionally, the spacing between a locking tab in the first group of locking tabs and an adjacent locking tab in the second group of locking tabs is greater than the spacing between a pair of adjacent locking tabs forming part of either of the first or second groups. In some embodiments an aperture is disposed between a pair or adjacent locking tabs which share a common outline, the aperture being struck in part from the first panel and defining in part a recess in the edge of the first panel such that the edge of the first panel defined by the recess is inset from a leading edge of the first panel.

Preferably, the at least a first one of the locking tabs comprises an engaging edge spaced from the free end edge of the first panel by a first distance. Preferably, the at least a second one of the locking tabs comprises an engaging edge spaced from the free end edge of the first panel by a second distance, the second distance being greater than the first distance.

Optionally, the engaging edge is a trailing edge of the locking tab.

Optionally, the at least a first one of the locking slits is spaced apart from the end edge of the second panel by a first distance.

Optionally, the at least a second one of the locking slits is spaced apart from the end edge of the second panel by a second distance, the second distance being greater than the first distance.

Optionally, the at least a first one of the locking slits comprises an abutment edge spaced from the free end edge of the second panel by a first distance.

Optionally, the at least a second one of the locking slots comprises an abutment edge spaced from the free end edge of the second panel by a second distance, the second distance being greater than the first distance. Optionally, the abutment edge is a defined by the locking slit.

Optionally, the locking tabs are each coupled to the first panel by a fold line for allowing the locking tabs to fold with respect to the first panel. Optionally, at least one first fold line coupling at least one first locking tab is disposed at first distance with respect to an end edge of the first panel and at least one second fold line coupling at least one second locking tab is disposed at second distance with respect to an end edge of the first panel, the second distance being greater than the first distance.

Preferably, the at least a first one of the locking tabs projects from the end edge of the first panel by a first dimension.

Optionally, the at least a second one of the locking tabs projects from the end edge of the first panel by a second dimension, the second dimension being greater than the first dimension.

According to a second aspect of the present invention there is provided a blank for forming a carton comprising a plurality of panels for forming a top panel base panel and opposing side walls interconnecting the top and base panels, wherein one of the plurality of panels is a composite panel comprising a first panel and a second panel, the blank comprising a locking arrangement, the arrangement comprising locking tabs projecting from an end edge of the first panel and locking slits provided adjacent an end edge of the second panel, wherein a locking slit is provided for receiving each of the respective locking tabs, the locking tabs and the locking slits being engageable by relative sliding movement therebetween, wherein at least one of the locking tabs or locking slits is configured to secure the first and second panels in a first overlapping position and at least one of the other the locking tabs or locking slits is configured to secure the first and second panels in a second overlapping position.

According to a third aspect of the present invention there is provided a carton comprising a plurality of panels including a top panel, a base panel and opposing side walls interconnecting the top and base panels, wherein one of the plurality of panels is a composite panel comprising a first panel and a second panel, the carton comprising a locking arrangement, the arrangement comprising locking tabs projecting from an end edge of the first panel and locking slits provided adjacent an end edge of the second panel, wherein a locking slit is provided for receiving each of the respective locking tabs, the locking tabs and the locking slits being engageable by relative sliding movement therebetween, wherein at least one of the locking tabs or locking slits is configured to secure the first and second panels in a first overlapping position and at least one of the other the locking tabs or locking slits is configured to secure the first and second panels in a second overlapping position. Optionally, the degree of overlap when the first and second panels are disposed in the second position is greater than the degree of overlap when the first and second panels are disposed in the first position, such that the carton has a smaller internal volume in the second position.

According to a fourth aspect of the present invention there is provided a locking arrangement for securing together a pair of panels, the pair of panels comprising a first panel and a second panel, the arrangement comprising at least one first locking tab projecting from an end edge of the first panel, at least one second locking tab projecting from an end edge of the first panel and at least one first locking slit provided adjacent an end edge of the second panel for receiving the at least one first locking tab and at least one second locking slit provided adjacent an end edge of the second panel for receiving the at least one first locking tab, wherein the at least one first locking tab and the at least one first locking slit are configured to secure the first and second panels in a first overlapping position and at least one second locking tab and at least one second locking slit are configured to secure the first and second panels in a second overlapping position.

According to a fifth aspect of the present invention there is provided a method for securing together a pair of panels, the pair of panels comprising a first panel and a second panel and including locking arrangement comprising at least one first locking tab projecting from an end edge of the first panel, at least one second locking tab projecting from an end edge of the first panel and at least one first locking slit provided adjacent an end edge of the second panel for receiving the at least one first locking tab and at least one second locking slit provided adjacent an end edge of the second panel for receiving the at least one first locking tab, wherein the at least one first locking tab and the at least one first locking slit are configured to secure the first and second panels in a first overlapping position and at least one second locking tab and at least one second locking slit are configured to secure the first and second panels in a second overlapping position, the method comprising;

determining whether to secure the pair of panels in the first or second overlapping position,

sliding the pair of panels with respect to one another so as to engage the at least one first locking tab with the at least one first locking slit so as to engage the pair of panels in the first overlapping position, and when securing the pair of panels in the second overlapping position, further sliding the pair of panels with respect to one another so as to engage the at least one second locking tab with the at least one second locking slit so as to engage the pair of panels in the second overlapping position.

According to a sixth aspect of the present invention there is provided a carton for packaging one or more articles, the carton comprising a plurality of panels including a top panel, a base panel and opposing side walls interconnecting the top and base panels, wherein one of the plurality of panels is a composite panel comprising a first panel and a second panel, the carton comprising a locking arrangement, the arrangement comprising locking tabs projecting from an end edge of the first panel and locking slits provided adjacent an end edge of the second panel, wherein a locking slit is provided for receiving each of the respective locking tabs, the locking tabs and the locking slits being engageable by relative sliding movement therebetween, wherein a portion of at least one of the locking tabs shares a common outline or weakened line of severance with a portion of at least one adjacent locking tab when the carton is in a blank form.

Preferably, the portion of the at least one of the locking tabs is complementary in shape to the portion of the at least one adjacent locking tab. This gives the at least one of the locking tabs the appearance of being struck from, or interrupted by, a portion of the at least one adjacent locking tab.

Within the scope of this application it is envisaged that the various aspects, embodiments, examples, features and alternatives set out in the preceding paragraphs, in the claims and/or in the following description and drawings may be taken independently or in any combination thereof. For example, features described in connection with one embodiment are applicable to all embodiments unless there is incompatibility of features.

BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary embodiments of the invention will now be described with reference to the accompanying drawings, in which:

FIGURE 1 is a plan view from above of a blank for forming a carton according to a first embodiment of the invention; FIGURE 2 is a perspective view from above of a portion of a locking mechanism according to the first embodiment of the invention in a stage of assembly;

FIGURE 3 is a perspective view from above of a portion of a locking mechanism according to the first embodiment of the invention in a later stage of assembly;

FIGURE 4A is a perspective view of a carton formed from the blank of Figure 1 in which a pair of panels is locked in a first overlapping position;

FIGURE 4B is a perspective view of a carton formed from the blank of Figure 1 in which a pair of panels is locked in a second overlapping position;

FIGURE 5 is a plan view from above of a blank for forming a carton according to a second embodiment of the invention;

FIGURE 6 is a plan view from above of a blank for forming a carton according to a third embodiment of the invention;

FIGURE 7 is a perspective view from above of a portion of a locking mechanism according to the third embodiment of the invention in a stage of assembly;

FIGURE 8 is a perspective view from above of a portion of a locking mechanism according to the third embodiment of the invention in an assembled condition;

FIGURE 9 a view from below of a portion of a locking mechanism according to the third embodiment of the invention in an assembled condition;

FIGURE 10 is a plan view from above of a blank for forming a carton according to a fourth embodiment of the invention;

FIGURE 1 1 is a fragmentary plan view of a blank for forming a carton according to a fifth embodiment of the invention; and

FIGURE 12 is another fragmentary plan view of the blank of FIGURE 1 1 , showing a portion of the blank different from a portion shown by FIGURE 1 1 .

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS OF THE PRESENT INVENTION

Detailed descriptions of specific embodiments of the package, blanks and cartons are disclosed herein. It will be understood that the disclosed embodiments are merely examples of the way in which certain aspects of the invention can be implemented and do not represent an exhaustive list of all of the ways the invention may be embodied. As used herein, the word "exemplary" is used expansively to refer to embodiments that serve as illustrations, specimens, models, or patterns. Indeed, it will be understood that the packages, blanks and cartons described herein may be embodied in various and alternative forms. The figures are not necessarily to scale and some features may be exaggerated or minimised to show details of particular components. Well-known components, materials or methods are not necessarily described in great detail in order to avoid obscuring the present disclosure. Any specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the invention.

Referring to Figure 1 there is shown a plan view from above of a blank 10 capable of forming a carton for packaging one or more primary products, such as, but not limited to, bottles or cans, hereinafter referred to as articles. In the embodiments detailed herein, the terms carton and carrier refer, for the non-limiting purpose of illustrating the various features of the invention, to a container for engaging, carrying, and/or dispensing articles, such as bottles. However, it is contemplated that the teachings of the invention can be applied to various containers, which may or may not be tapered and/or cylindrical. Other exemplary articles include bottles (for example metallic, glass or plastics bottles), cans (for example aluminium cans), tins, pouches, packets and the like.

The blank is formed from a sheet of suitable substrate. It is to be understood that, as used herein, the term "suitable substrate" includes all manner of foldable sheet material such as paperboard, corrugated board, cardboard, plastic, combinations thereof, and the like. It should be recognized that one or other numbers of blanks may be employed, for example, to provide the carrier structure described in more detail below.

In the exemplary embodiment, the blank is configured to form a carton or carrier for packaging an exemplary arrangement of exemplary articles. For example, the arrangement is a matrix including rows and columns such as a 2X2 arrangement of articles. The blank can be alternatively configured to form a carrier for packaging other articles and/or different arrangements of articles.

Blank 10 comprises a linear series of panels 12, 14, 16, 18, 20, 22, 24, 26, 28, 28a hinged one to the next by a respective fold line 13, 15, 17, 19, 21 , 23, 25, 27. Blank 10 comprises a pair of end closure structures 30a, 30b which partially close ends of the carton assembled form the blank 10. In other embodiments it is envisaged that the end closure structures 30a, 30b may fully close the ends of the carton. The blank 10 comprises a first base panel 12 hinged to a first bevelled panel 14 by a fold line 13. First bevel panel 14 is hinged to a first lower side panel 16 by a fold line 15. First lower side panel 16 is hinged to a first upper side panel 18 by a fold line 17. First upper side panel 18 is hinged to a top panel 20 by a fold line 19. Top panel 21 is hinged to a second upper side panel 22 by a fold line 21. Second upper side panel 22 is hinged to a second lower side panel 24 by a fold line 23. Second lower side panel 24 is hinged to a second bevel panel 26 by a fold line 25. Second bevel panel 26 is hinged to a second base panel 28 by a fold line 27. Second base panel 28 is hinged to a hinge panel 28a by a fold line 52. First end closure structure 30a comprises a first top end closure panel 32a hinged to the top panel 20 by a fold line 31 a. A first web panel 34a is hinged to first top end closure panel 32a along a first side edge, by a fold line 33a. A second web panel 36a is hinged to first top end closure panel 32a along a second side edge, by a fold line 35a. A first gusset panel 38a interconnects first web panel 34a to a first anchor panel 42a, first gusset panel 38a is hinged to first web panel 34a by a fold line 39a and to first anchor panel 42a by a fold line 43a. A second gusset panel 40a interconnects second web panel 36a to a second anchor panel 44a, second gusset panel 40a is hinged to second web panel 36a by a fold line 37a and to second anchor panel 44a by a fold line 41 a. First anchor panel 42a is hinged to first upper side panel 18 by a fold line 7a. Second anchor panel 44a is hinged to second upper side panel 22 by a fold line 9a. An aperture A separates the first gusset panel 38a from the first upper side panel 18 and the top panel 20. An aperture A separates the second gusset panel 40a from the second upper side panel 22 and the top panel 20.

Second end closure structure 30b comprises a second top end closure panel 32b hinged to the top panel 20 by a fold line 31 b. A third web panel 34b is hinged to second top end closure panel 32b along a first side edge, by a fold line 33b. A fourth web panel 36b is hinged to second top end closure panel 32b along a second side edge, by a fold line 35b. A third gusset panel 38b interconnects third web panel 34b to a third anchor panel 42, third gusset panel 38b is hinged to third web panel 34b by a fold line 39b and to third anchor panel 42b by a fold line 43b. A fourth gusset panel 40b interconnects fourth web panel 36b to a fourth anchor panel 44b, fourth gusset panel 40b is hinged to fourth web panel 36b by a fold line 37b and to fourth anchor panel 44b by a fold line 41 b. Third anchor panel 42b is hinged to first upper side panel 18 by a fold line 7b. Fourth anchor panel 44a is hinged to second upper side panel 22 by a fold line 9b. An aperture A separates the third gusset panel 38b from the first upper side panel 18 and the top panel 20. An aperture A separates the fourth gusset panel 40b from the second upper side panel 22 and the top panel 20.

Blank 10 comprises a means for locking the first and second base panels 12, 28 together. The locking mechanism 70 comprises a male M portion and a female portion F forming a first part of a complimentary locking mechanism 70 and second part of a complimentary locking mechanism 70.

Referring now to Figure 1 to 3 the first part M of the complimentary locking mechanism 70 comprises a male locking tab 54/54a, 56/56a, 58/58a which is coupled to the first base panel 12 along fold lines 55, 57, 59 respectively. The male locking tabs 54/54a, 56/56a, 58/58a project outwardly, in the plane of the first base panel 12, from the end edge 16 thereof. The male locking tab 54/54a, 56/56a, 58/58a comprises a main portion 54, 56, 58 and an integral anchoring tab 54a, 56a, 58a which is hinged to one side edge of the main portion 54, 56, 58 along a fold line 61 , 63, 65 respectively. The fold lines 61 , 63, 65 are substantially perpendicular to the end edge 16 of first base panel 12. The trailing edge 66 of the anchoring tab is spaced from end edge 16 and, in use, provides a locking edge for cooperation with an abutment edge defined by a locking slit in second base panel 28. In alternative embodiments the main portion 54, 56, 58 may formed to include a nose which projects beyond the foldable anchoring tab 54a, 56a, 58a to lead insertion of the male locking tab 54/54a, 56/56a, 58/58a in a locking slit of second base panel 28.

Second base panel 28 includes a locking slit 50a, 50b, 50c in the form of a shallow "Y" which is struck from second base panel 28 along a fold line 52 extending parallel to the end edge 1 1 of second base panel 28. Thus, second base panel 28 has a foldable front edge strip or hinge panel 28a. The slit 50a, 50b, 50c is formed by a continuous cut line comprising a first part extending along hinge panel 28a towards the end edge of the second base panel 28 at an acute angle with respect to fold line 52; a return part extending back to meet fold line 52 at an acute angle with respect thereto; and an leg part extending substantially perpendicularly to fold line 52 from the vertex between the first part and the return part. When front edge strip 32 is folded out of the plane of the blank the slit 50a, 50b, 50c is opened and the first and return parts define a guide projection 49a extending outwardly from fold line 52. The upright leg portion of the "Y" shaped cut allows the material forming the hinged panel 28a above the aperture created by folding the hinge panel 28a to flex or bend when inserting the male locking tabs 54/54a, 56/56a, 58/58a. In order to lock together first and second base panels 12 and 28, first the anchoring tabs 54a, 56a, 58a are folded 180 degrees about fold lines 61 , 63, 65 respectively into face contacting relationship with the underside of the respective main portion 54, 56, 58. Also, the hinge panel 28a is folded about fold line 52 out of the plane of the blank (Figure 2) to open the slits 50a, 50b, 50c. Once the anchoring tabs 54a, 56a, 58a have been folded thus, the maximum transverse dimension (corresponding to the maximum width of the main portions 54, 56, 58) from fold line 61 , 63, 65 to the opposite edge of the respective male locking tab 54/54a, 56/56a, 58/58a is sized so that the male locking tab 54/54a, 56/56a, 58/58a can be slidingly engaged in a respective one of the locking slits 50a, 50b, 50c. The locking tabs 54/54a, 56/56a, 58/58a may be an interference fit in the locking slits 50a, 50b, 50c. Hence, locking tabs 54/54a, 56/56a, 58/58a can be inserted into the locking slits 50a, 50b, 50c until the trailing edge 66 of the anchoring tabs 54a, 56a, 58a has moved past, that is to say, cleared the abutment edge 68 of the locking slits 50a, 50b, 50c. The natural resilience of the paperboard material then allows the folded anchoring tabs 54a, 56a, 58a automatically to spring back into a more upright position unless otherwise constrained whereby the trailing edge 66 at or adjacent fold line 61 , 63, 65 is brought into a position in which it will abut against the abutment edge 68 when tension is applied to the first and second base panels 12, 28 in opposition to the locking direction i.e. in a direction tending to move the panels apart. Thus, the abutting engagement between edge 66 and edge 68 of the locking slits 50a, 50b, 50c maintains the first and second base panels 12, 28 locked together. The projection 49a aids in the alignment of the locking tabs 54/54a, 56/56a, 58/58a into the slits 50a, 50b, 50c during locking.

In some circumstances, such as when the panels 12, 28 are base panels of a carton and packed articles are disposed upon the interlocked panels 12, 28, both the hinge panel 28a of panel 28 and the anchoring tabs 54a, 56a, 58a may be flat, that is parallel to the plane of the panels 12, 28. Nevertheless, the abutment between trailing edge 66 at or adjacent fold lines 61 , 63, 65 and abutment edge 68 maintains the panels interlocked. Moreover, the double-ply thickness of material provided by both the main portions 54, 56, 58 and anchoring tabs 54a, 56a, 58a is sufficient to prevent withdrawal of the locking tab 54/54a, 56/56a, 58/58a from the locking slits 50a, 50b, 50c. It will be appreciated that in this locking configuration, the trailing edge 66 lies substantially parallel to the abutment edge 68 to enhance the engagement between the panels.

Central locking tab 56/56a which is disposed between locking tabs 54/54a, 58/58a is configured to provide a tighter locking position than the outer locking tabs 54/54a, 58/58a. In which the degree of overlap of the first base panel 12 with the second base panel 28 is greater than which is achieved by engaging the outer locking tabs 54/54a, 58/58a. This is achieved by offsetting the abutment edge 66 of the locking tab 56/56a from the abutment edges of the outer locking tabs 54/54a, 58/58a. The abutment edge 66 of the locking tab 56/56a is disposed in closer proximity to the edge 64 of first base panel 12 than the abutment edges 66 of the outer locking tabs 54/54a, 58/58a; the abutment edge 66 of the locking tab 56/56a is offset by a distance O from the abutment edges 66 of the outer locking tabs 54/54a, 58/58a. The outer locking tabs 54/54a, 58/58a extends from the edge 64 of first base panel 12 by a first dimension L1 . The central locking tab 56/56a extends from the edge 64 of first base panel 12 by a second dimension L2. The first dimension L1 is greater than the second dimension L2. The staggered or offset arrangement of the leading edges of the locking tabs 54/54a, 56/56a, 58/58a provides that only the outer locking tabs 54/54a, 58/58a need to be aligned simultaneously, thereby simplifying assembly of the carton 90. Alignment of the central locking tab 56/56a with its respective locking slit 50b is aided or facilitated by the offset arrangement of the leading edges of the locking tabs 54/54a, 56/56a, 58/58a, since the central locking tab 56/56a is constrained once the outer locking tabs 54/54a, 56/56a, 58/58a have been inserted into their respective locking slits 50a, 50c.

In the illustrated embodiment the male locking tabs 54/54a, 56/56a, 58/58a are coupled to the first base panel 12 by a respective fold line 55, 57, 59. In alternative embodiments the fold lines 55, 57, 59 may be omitted.

Optionally, the fold line 57 coupling the locking tab 56/56a to the first base panel 12 is offset from the fold lines 55, 59 coupling the outer locking tabs 54/54a, 58/58a to the first base panel 12. The fold line 57 is disposed in closer proximity to, preferably co-linear with, the edge 64 of first base panel 12 than the fold lines 55, 59 of the outer locking tabs 54/54a, 58/58a. The outer locking tabs 54/54a, 58/58a are coupled to a small projection extending from the first base panel 12 in this way the leading edge of the outer locking tabs 54/54a, 58/58a is disposed further from the free end edge of the first base panel 12 than the leading edge of the central locking tab 56/56a, the outer locking tabs 54/54a, 58/58a are thereby brought into contact with the second base panel 228 and hinge panel 228a before the central locking tab 56/56a.

In this way when bringing the first base panel 212 and second base panel 228 together the outer locking tabs 54/54a, 58/58a may contact the hinge panel 228a and slide over the hinge panel 228a until the outer locking tabs 54/54a, 58/58a contact the projection 49a to align the outer locking tabs54/54a, 58/58a with the outer locking slits 50a, 50c.

Turning to the construction of the carton 90 as illustrated in Figures 4A and 4B, it is envisaged that the carton 90 can be formed by a series of sequential folding operations in a straight line machine so that the carton 90 is not required to be rotated or inverted to complete its construction. The folding process is not limited to that described below and may be altered according to particular manufacturing requirements. The carton 90 is formed by wrapping the blank 1 10 about one or more articles (not shown). The top panel 20 is disposed over a group of articles, the top end closure panels 32a, 32b are folded about the ends of the article group by folding the anchor panel 42a, 42b, 44a, 44b abut fold line 43a, 43b, 41 a, 41 b respectively so as to be substantially in face contacting relationship with the first or second upper side panel to which each anchor panel 42a, 42b, 44a, 44b is hinged. This automatically folds the top end closure panels 32a, 32b and web panels 34a, 34b, 36a, 36b about the group of articles. The first and second upper side panels 18, 22 are folded (along with the first and second lower side panels 16, 24, first and second bevel panels 14, 26 and first and second base panel 12, 28) about fold lines 19, 21 respectively to place the anchor panels 42a, 42b, 44a, 44b between the group of article and the respective first or second upper side panel 18, 22; thus anchoring the top end closure panels 32a, 32b in position.

The first and second bevel panels 14, 26 when provided are folded about fold line 15, 25 respectively about the lower portion of the article group. The first and second base panels 12, 28 are folded about the fold lines 13, 28 respectively so as to be disposed below the group of articles. The complimentary locking mechanisms 70 are employed as described above to lock the first base panel 12 and second panel 28 together. The first and second base panels 12, 28 may be locked in either a first overlapping position, as shown in Figure 4A, in which the outer locking tabs 54/54a, 58/58a are fully engaged or fully inserted with the locking slits 50a, 50c or a second overlapping position, as shown in Figure 4B, in which all locking tabs 54/54a, 56/56a, 58/58a are fully engaged or fully inserted with the locking slits 50a, 50b, 50c depending upon the dimensions of the article group being packaged and/or the tightness of the carton about the group of articles required. In the first position as illustrated in Figure 4A the central locking tab 56/56a is maintained in a folded condition, such that the anchor tab 56a is substantially in face contacting relationship with main portion 56 of the central locking tab 56/56a. The anchor tabs 54a, 58a of each of the endmost or outer locking tabs 54/54a, 58/58a have passed through the respective locking slit 50a, 50c and have partially unfolded, due to the inherent resilience of the material of the blank 10, such the anchor tabs 54a, 58a are in locking engagement with the hinge panel 28a.

The carton 90 in the first position or assembly configuration, as shown in Figure 4A, comprises a composite base panel 12/28 formed from the first and second base panels 12, 28, the composite base panel 12/28 has width dimension W1 defined between the first bevel panel 14 and the second bevel panel 26. The carton 90 in the second position or assembly configuration, as shown in Figure 4B, comprises a composite base panel 12/28 formed from the first and second base panels 12, 28, the composite base panel 12/28 has width dimension W2 defined between the first bevel panel 14 and the second bevel panel 26. The width dimension W2 is less than the width dimension W1 such that the first second bevel panel 14 is disposed closer to the second bevel panel 26 in the second position than in the first position.

In the second position the degree of overlap of the first base panel 12 with the second base panel 28 is greater than the degree of overlap of the first base panel 12 with the second base panel 28 when disposed in the first position.

In the second position the anchor tab 56a of the central locking tab 56/56a in addition to the anchor tabs 54a, 58a of each of the endmost or outer locking tabs 54/54a, 58/58a have passed through the respective locking slit 50a, 50b, 50c and have partially unfolded, due to the inherent resilience of the material of the blank 10, such the anchor tabs 54a, 56a, 58a are in locking engagement with the hinge panel 28a.

In the first position trailing edge 66 of each of the outer locking tabs 54/54a, 58/58a is in abutment with abutment edge 68 of the hinge panel 28a. The hinge panel 28a prevents the anchor tab 56a from unfolding since the hinge panel 28a is disposed over the anchor tab 56a of the locking tab 56/56a.

In the second position trailing edge 66 of the central locking tab 56/56a is in abutment with abutment edge 68 of the hinge panel 28a. The anchor tabs 54a, 56a, 58a are all unfolded. The trailing edge 66 of each of the outer locking tabs 54/54a, 58/58a may be spaced apart from the abutment edge 68 of the hinge panel 28a. The outer locking tabs 54/54a, 58/58a each serve to stabilise the interlocking arrangement of the first and second base panels 12, 28. Referring now to Figures 5 to 1 1 , there is shown alternative embodiments of the present invention. In the second, third, fourth and fifth illustrated embodiments, like numerals have, where possible, been used to denote like parts, albeit with the addition of the prefix "100", "200", "300" or "400" to indicate that these features belong to the second, third, fourth or fifth embodiment. The alternative embodiments share many common features with the first embodiment and therefore only the differences from the embodiment illustrated in Figures 1 to 4 will be described in any greater detail.

Figure 5 illustrates a blank 1 10 for forming a carton according to a second embodiment, blank 1 10 comprises four apertures A1 struck at least in part from the top panel 120. Two of the apertures interrupt the fold line 121 between the top panel 120 and the second upper side panel 122. Apertures A1 may each receive a portion of a respective article such as a neck portion or upper portion.

The blank 1 10 comprises four complimentary locking mechanisms and include four male locking tabs 154, 156, 158, 160 and four locking slits 150a, 150b, 150c, 150d. The four male locking tabs 154, 156, 158, 160 are arranged in a linear series so as to be in close proximity with at least one adjacent male locking tabs 154, 156, 158, 160; The anchor tab of locking tab 154 is shaped to be complimentary to an edge portion of the main portion of the adjacent locking tab 156, anchor tab of locking tab 156 is shaped to be complimentary to an edge portion of the main portion of the adjacent locking tab 158, anchor tab of locking tab 158 is shaped to be complimentary to an edge portion of the main portion of the adjacent locking tab 160. It will be appreciated that each male locking tabs 154, 156, 158, 160 shares a common outline or weakened line of severance with at least one adjacent male locking tabs 154, 156, 158, 160. The locking slits 150a, 150b, 150c, 150d are arranged in a linear series and interrupt the fold line 152 coupling the hinge panel 128a to the second base panel 28. The central pair of locking slits 150b, 150c is disposed in closer proximity to the fold line 127 between the second base panel 128 and the second bevel panel 126 than the locking slits 150a, 150d at each end of the linear series. Each of the central pair of locking slits 150b, 150c is offset by a distance O with respect to the locking slits 150a, 150d at each end of the linear series. The central locking slits 150b, 150c are disposed at a first distance x from the free end edge of the second base panel 128 and the endmost locking slits 150a, 150d are disposed at a second distance y from the free end edge of the second base panel 128; the second distance y is less than the first distance x.

Blank 1 10 comprises three apertures 155, 157, 159; first aperture 155 is disposed between first locking tab 154 and second locking tab 156, second aperture 157 is disposed between second locking tab 156 and third locking tab 158, and third aperture 159 is disposed between third locking tab 158 and fourth locking tab 160. Each of the first, second and third apertures 155, 157, 159 is struck in part from the first base panel 1 12 such that a portion of the edge of the first base panel defined by each of the first, second and third apertures 155, 157, 159 is offset from a leading edge of the first base panel defined by fold lines hingedly connecting the male locking tabs 154, 156, 158, 160 to the first base panel 1 12. When the hinge panel 128a is folded about the fold line 152 the offset O between the central pair of locking slits and the endmost locking slits places the endmost locking slits 150a, 150d in closer proximity to the fold line 127 between the second base panel 128 and the second bevel panel 126 than the central pair of locking slits 150b, 150c. The blank 1 10 can be formed into a carton which comprises two locking positions:

A first locking position in which the first and second base panels 1 12, 128 are disposed in overlapping relationship, the region of overlap defining a first overlapping area. In the first locking or overlapping position the endmost locking tabs 154, 160 are each in locking engagement with respective endmost locking slit 150a, 150d in which they are received. The central locking tabs 156, 158 are not fully inserted into the respective locking slit 150b, 150c such that the anchor tab of each of the central locking tabs 156, 158 is maintained in a folded relationship, with respect to the respective main portion of the central locking tabs 156, 158 to which it is hinged, by the hinge panel 128a. A second locking position in which all the locking tabs 154, 156, 158, 160 are fully inserted or engaged with the respective locking slit 150a, 150b, 150c, 150d in which they are received, the central locking tabs 156, 158 are each in locking engagement (the trailing edge of the anchor tab is in abutment with the abutment edge of the locking slit 150b, 150c) with the central locking slits 150b, 150c and the trailing edge of the anchor tab of each of the endmost pair of locking tabs 154, 160 is spaced apart from the abutment edge of the respective locking slit 150a, 150d.

In an alternative embodiment the central pair of locking tabs 156, 158 are spaced apart from one another, a first endmost locking tab 154 being in contact with a first one of the central locking tabs 156, and a second endmost locking tab 160 being in contact with a second one of the central locking tabs 158. In this way the locking tabs 154, 156, 158, 160 are arranged in two distinct groups, wherein the groups are spaced apart from one another but the locking tabs 154, 156, 158, 160 in each group are substantially in contact with one another when formed in the blank 1 10. It is envisaged that the locking slits 150a, 150b, 150c, 150d will be arranged so as to receive a respective one of the locking tabs 154, 156, 158, 160. In such arrangements it is envisaged that each locking tab or locking slit in a group may lock the first and second base panels 1 12, 128 in the same locking position or in different locking positions. In this way a first group of locking tabs and locking slits may lock the first and second base panels 1 12, 128 in a first position and a second group of locking tabs and locking slits may lock the first and second base panels 1 12, 128 in a second position.

Turning now to Figures 6 to 10 there is shown a blank 210 for forming a carton according to a third embodiment. Blank 210 comprises an alternative locking mechanism, which includes a male locking member 280a, 280b, 280c

Blank 210 comprises three complementary locking devices. Blank 210 comprises a first part F of a complementary locking device and a second part M of a complementary locking device. First part F comprises a flap 228a hingedly connected to a first panel 228 by fold line 252, first panel 228 forms a second base panel of a carton.

Fold line 252 is interrupted by a cut lines or weakened lines of severance 250a, 250b, 250c. Cut lines 250a, 250b, 250c are at least partially offset from fold line 252. In the illustrated embodiment the cut lines 250a, 250b, 250c are disposed or located within flap 228a, such that each defines in part a first projection 289a, 289b, 289c, which first projections 289a, 289b, 289c are integrally formed with the first panel 228. Cut lines 250a, 250b, 250c are stepped or tiered in shape; a central linear portion defines a leading edge of first projections 289a, 289b, 289c. First linear section defines a first tier. A second tier is disposed on either side of the first tier. Second tier is defined by outer portions 287a, 288a of outline 250a and is disposed closer to fold line 252 than the first tier. The outer portions 287a, 288a defining the second tier are preferably disposed at an angle with respect to the fold line 252 and with respect to the first tier; the outer edges of the outer portions 287a, 288a of outline 250a defining the second tier being disposed closer to the fold line 252 than the inner edges of the outer portions 287a, 288a.

The portion of the cut lines 250a, 250b, 250c defining the first tier define a recess or aperture A2 in flap 228a in a folded condition, which recess or aperture A2 is arranged to receive a portion of the second part M of the complementary locking mechanism.

The second part M comprises a foldable tab 280a, 280b, 280c hingedly connected to a second projection along a fold lines 282a, 282b, 282c respectively. The second projections extend from a free edge of a second panel 212, which forms a first base panel of a carton. The fold line 282a, 282b, 282c are interrupted by a cut lines or weakened lines of severance; the cut lines are arcuate in shape and each forms a tab 284a, 284b, 284c which is struck from material forming a respective one of the second projections. The tabs 284a, 284b, 284c are integral with respective ones of the foldable tabs 280a, 280b, 280c. A free end edge of each foldable tab 280a, 280b, 280c opposing the respective fold lines 282a, 282b, 282c is stepped or tiered in shape; an endmost, first, tier defines in part a tongue 292a disposed centrally within the tab 280a. Tongue 292a is sized and arranged to be received in the recess or aperture A2.

Outer portions define in part the second tier of the foldable tab 280a, each outer portion having an engaging edge 299a, 299b respectively; the second tier is disposed in closer proximity to the fold line 282a than the first tier.

The second tier forms shoulders on either side of the central tongue 292a. Preferably, in the folded state, the tab 280a overlaps with the second panel 212 by a distance Z, as illustrated in Figure 7; the distance Z is sufficiently large that tab 280a cannot pass entirely through the aperture A2, even when the flap 228a is coplanar with the first panel 228. Turning to the assembly of the complementary locking devices as illustrated in Figures 7 to10, it is envisaged that the complementary locking devices can be formed by a series of sequential folding operations in a straight line machine so that the carton is not required to be rotated or inverted to complete its construction. The folding process is not limited to that described below and may be altered according to particular manufacturing requirements.

Figure 7 illustrates a stage of assembly of the complementary locking devices. The flap 228a has been folded about fold line 252. The flap 228a is illustrated folded to be perpendicular to first panel 228. In other embodiments the flap 228a may be folded through an angle less than 90 degrees, or may be allowed to at least partially unfold (see Figure 8), so as to define an obtuse angle between flap 228a and first panel 228. In folding the flap 228a, an aperture A2 has been created between the flap 228a and the first panel 228.

Foldable tabs 280a, 280b, 280c are folded about fold Iines282a, 282b, 282c, into substantially overlapping or overlying relationship with the respective second projection and at least a portion of second panel 212.

The first and second panels 228, 212 are moved with respect to one another as indicated by directional arrows D1 , D2 and D3 so as to insert the folded tabs 280a, 280b, 280c into aperture A2. As illustrated in Figure 9 the tab 280a, in a folded condition, at least partially passes through the aperture A2. The tab 280a engages with the aperture A2 created by folding the flap 228a. The tongue 292a engages with an upper edge 291 a of the aperture A; upper edge 291 a defines at least in part the recess in which the tongue 292a is received. In this way the upper edge 291 a restricts the tab 280a from unfolding. The engaging edges 299a, 299b of the outer portions of tab 280a engage with the flap 228a at locations disposed adjacent to the recess.

In the illustrated embodiment of Figure 8, the flap 228a has unfolded, at least partially, about fold line 252, so as to define an obtuse angle between the flap 228a and the first panel 228a. Similarly, the tab 280a has partially unfolded about fold line 282a. Tongue 292a of tab 280a is received in the recess.

Shoulder portions 286a, 285a engage with those portions of flap 228a disposed on either side of the recess and defined in part by cut lines 250a, 250b, 250c. Upward travel, unfolding, of the tabs 280a, 280b, 280c is limited by the flap 228a.

Tab 284a engages with first panel 228 limiting unfolding of foldable tab 280a.

It will also be appreciated that tab 280a in the folded condition is tapered so that it is narrower in width towards the leading edge. This assists in aligning the tab 280a with the aperture A2, since the leading edge is smaller in dimension than the aperture A2.

It will also be understood that if the tab 280a is inserted entirely through aperture A2 inadvertently, then the first and second panels 228,212 remain locked together since the tab 280a, 280b, 280b cannot unfold into a flat condition by virtue of the arcuate tab 284a, 284b, 284c, which engages first panel 228 preventing unfolding.

Figure 9 illustrates the first and second panels 228, 212 in a locked condition. The projection 289a at least partially overlaps with second panel 212; the projection 289a being disposed outermost. This overlapping relationship is optional, but when provided increases security by preventing or reducing folding of first panel 228 about fold line 252, thereby helping to maintain first and second panels 228, 212 in a substantially co-planar, or at least substantially parallel, relationship with one another. The blank 210 provides two locking positions:

a first locking position in which the endmost male locking tabs 280a, 280c are in locking engagement with the endmost (or outer) locking slits 250a, 250c or apertures A2 and the of the central foldable tab 280b of the central male locking tab 280b is maintained in a folded relationship with respect to the respective second projection to which the central foldable tab 280b is hinged, the tongues 291 b of the central male locking tabs 280b is prevented from being received in the respective recess of the flap 228a, the shoulder portions 286a, 285a of the central male locking tab 280b has not passed through its respective locking slit or aperture and as such the central male locking tab 280b is not in locking engagement with the flap 228a; a second locking position in which all the locking tabs 280a, 280b, 280c are fully inserted into the respective locking apertures A2 in which they are received, the central locking tab 280b is in locking engagement (the tongue of the foldable tabs 280b is received within the respective recess of the a first part F of the complementary locking device defined in flap 228a) and the shoulder portions 286a, 285a of the central male locking tab 280b has passed through its respective locking slit or aperture such that the central male locking tab 280b is in locking engagement with the flap 228a and wherein the endmost foldable tabs 280a, 280c are further inserted into the respective apertures A2 such that the engaging edges 299a, 299b of the outer portions of endmost foldable tabs 280a, 280c are spaced apart from the flap 228a, in some embodiments the endmost foldable tabs 280a, 280c may pass through the apertures A2 in their entirety, in this second position the endmost foldable tabs 280a, 280c are substantially prevented or restricted from unfolding or returning to the plane of the second panel 212 by engagement of the tab 284a, 284c with the first panel 228. Referring now to Figure 10 there is shown a blank 310 for forming a carton according to a fourth embodiment. Blank 310 comprises an alternative locking arrangement which includes comprises a first part M of a complementary locking device and a second part F of a complementary locking device. In the embodiment of Figure 10 the male locking tabs 354, 356, 358 have an alternative shape and configuration. There are provided three male locking tabs 354, 356, 358 arranged in a linear series disposed along and extending from a free end edge of the first base panel 212. The endmost male locking tabs 354, 358 comprise an arcuate leading edge which is optionally substantially hemispherical. The endmost male locking tabs 354, 358 comprise a recess which defines a trailing edge for abutment with the second part F of the complementary locking device. The recess in male locking tab 354 is on an opposing side of the male locking tab 354 to the recess in male locking tab 358, preferably the recesses are both on outermost side edges of each of the male locking tabs 354, 358, that is to say the recesses are disposed on the side edge of the male locking tabs 354, 358 in closest proximity to the open ends of the tubular structure defined by the carton walls 312, 314, 316, 318, 320, 322, 324, 326, 328. The central male locking tab 356 comprises an arcuate leading edge, which is optionally substantially hemispherical, and comprises a pair of recesses defined on opposing side edges thereof, the recesses each define a trailing edge for abutment with the second part F of the complementary locking device, in this way the central male locking tab 356 has substantially mushroom shaped appearance.

The recesses struck from the central male locking tab 356 are smaller in dimension than those struck from each of the endmost male locking tabs 354, 358 in this way the trailing edges of the central male locking tab 356 are in closer proximity to the free end edge of the first base panel 312 than the trailing edges of the endmost male locking tabs 354, 358, in this way a carton formed from the blank 310 comprises two distinct locking positions in which the degree of overlap between the first base panel 312 and second base panel 328 can be adjusted so as to increase or decrease the dimension of the tubular structure formed by the carton walls 312, 314, 316, 318, 320, 322, 324, 326, 328. In this way the carton can be adjusted to ensure a tight fit of the carton about its contents, whereby allowing for compensation in dimensional differences of the carton contents. Figures 1 1 and 12 illustrate a blank 450 for forming a carton according to a fifth embodiment. Figures 1 1 and 12 shows the area of a first base panel 412 and the area of a second base panel 428 only. The other area of the blank 40 is identical to that of the blank 1 10 of the second embodiment.

Referring to Figure 1 1 , locking tabs 454, 456, 458, 460 are arranged in first and second groups. The locking tabs 454, 456 in the first group share a common outline 462 whereas the locking tabs 458, 460 in the second group share a common outline 463. The locking tabs 454, 456 in the first group are spaced apart from the locking tabs 458, 460 in the second group. More particularly, the locking tab 456 in the first group is spaced apart from the locking tab 458 in the second group. The spacing between the locking tab 456 and the locking tab 458 is greater than the spacing between the adjacent locking tabs 454, 456 of the first group or that between the adjacent locking tabs 458, 460 of the second group. An aperture 455 is defined between the locking tabs 454, 456 which share the common outline 462 while an aperture 459 is defined between the locking tabs 458, 460 which share the common outline 463. Each aperture 455, 459 is struck in part from the first base panel 412 and defines in part a recess along the end edge of the first base panel. Referring to Figure 12, locking slits 450a, 450b, 450c, 450d are arranged in two groups and substantially in a linear series. They interrupt the fold line 452 which couples a hinge panel 428a to the second base panel 428. The locking slit 450b of the first group is spaced from the locking slit 450c of the second group. The locking slits 450a, 450b of the first group are spaced from one another. The locking slits 450c, 450d of the second group are spaced from one another similarly to the locking tabs 450a, 450b in terms of spacing. The spacing between the locking slits 450b, 450c is greater than the spacing between the locking slits in the first group or in the second group. Each of the locking slits 450b, 450c is offset by a distance O with respect to the locking slits 450a, 450d. The central locking slits 450b, 450c are disposed at a first distance x from the free end edge of the second base panel 428 and the endmost locking slits 450a, 450d are disposed at a second distance y from the free end edge of the second base panel 128. The second distance y is less than the first distance x.

It can be appreciated that various changes may be made within the scope of the present invention, for example, the size and shape of the panels and apertures may be adjusted to accommodate articles of differing size or shape. In other embodiments of the invention it is envisaged that the locking arrangement may comprise more than two locking positions; in which further locking tabs and further locking slits respectively are provided for providing further locking positions having greater or lesser degrees of overlap between the first and second base panels than the first and second position disclosed hereinabove, such embodiments may comprise three or more locking positions. In other embodiments it will be appreciated that the locking arrangement may comprise a plurality of male locking tabs offset with respect to each other so as to provide different position of engagement and a plurality of female locking slits or apertures offset with respect to each other so as to provide different position of engagement, in some embodiment the male tabs and female slits may be arranged to give progressively tighter positions of engagement (increasing the degree of overlap between the first and second panels) or they may be arranged such that the offset of the male tabs functions in opposition to the offset of the female tabs so as to cancel one another out, in such an arrangement the carton will only have one locking position but the respective locations at which the male and female portions engage with one another will be offset from one another. For example in one embodiment a locking arrangement is provided comprising two locking tabs projecting from an end edge of a first panel and two locking slits provided adjacent an end edge of the second panel. A locking slit is provided for receiving each of the respective locking tabs, the locking tabs and the locking slits being engageable by relative sliding movement of the locking tabs into the locking slits. A first one of the locking tabs and a first one of the locking slits are configured to secure the pair of panels in an at least partially overlapping relationship. A first point of engagement between the first and second panels is defined by the position that the first locking tabs and the first locking slit engage one another, the first point of engagement and is disposed at first location. A second one of the locking tabs and a second one of the locking slits are also configured to secure the pair of panels in an at least partially overlapping relationship. A second point of engagement between the first and second panels is defined by the position that the second locking tabs and the second locking slit engage one another; the second point of engagement is at second location. The first location is spaced at a first distance from a free end edge the first or second panel and the second location is spaced at a second distance from a free end edge the first or second panel the second distance being greater than the first distance. In this way the first and second points of engagement are offset from one another with respect to an edge of the composite panel formed by securing the first and second panels together; when the locking arrangement is employed in a wraparound style carton the first and second points of engagement are offset from one another with respect to a tubular axis of the carton.

It will be recognised that as used herein, directional references such as "top", "bottom", "front", "back", "end", "side", "inner", "outer", "upper" and "lower" do not limit the respective panels to such orientation, but merely serve to distinguish these panels from one another.

As used herein, the terms "hinged connection" and "fold line" refers to all manner of lines that define hinge features of the blank, facilitate folding portions of the blank with respect to one another, or otherwise indicate optimal panel folding locations for the blank. A fold line is typically a scored line, an embossed line, or a debossed line. Any reference to hinged connection or fold line should not be construed as necessarily referring to a single fold line only; indeed it is envisaged that hinged connection can be formed from any one or more of the following, a short slit, a frangible line or a fold line without departing from the scope of the invention.

As used herein, the term "severance line" refers to all manner of lines that facilitate separating portions of the substrate from one another or that indicate optimal separation locations. Severance lines may be frangible or otherwise weakened lines, tear lines, cut lines, or slits.

It should be understood that hinged connection, severance lines and fold lines can each include elements that are formed in the substrate of the blank including perforations, a line of perforations, a line of short slits, a line of half-cuts, a single half-cut, a cut line, an interrupted cut line, slits, scores, any combination thereof, and the like. The elements can be dimensioned and arranged to provide the desired functionality. For example, a line of perforations can be dimensioned or designed with degrees of weakness to define a fold line and/or a severance line. The line of perforations can be designed to facilitate folding and resist breaking, to facilitate folding and facilitate breaking with more effort, or to facilitate breaking with little effort.