Carton panel lock

Abstract
A mechanical lock assembly for a wrap-around carton. The mechanical lock assembly has a primary variable lock belt, which both prevents withdrawal of a locking tab after it has been inserted into a locking opening of an associated overlapping panel flap, and enables the lock to adjust according to the size carried items. A secondary locking system prevents the primary locking system from disengaging.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




This invention relates generally to mechanical locks for holding overlapping flaps of a wrap-around carton in place. More particularly, it relates to a belt lock that provides a variable lock size.




2. Prior Art




When fabricating a carton from a paperboard blank, opposite ends of the blank are conventionally attached to each other by glue or by a mechanical lock to form the bottom panel of the carton. In the case of a wrap-around carton, flaps located on the ends of the blank typically are overlapped and engaged with one another by mechanical locks formed in the flaps to form the bottom panel of the carton. Since the bottom panel must maintain its integrity throughout the use of the carton, it is essential that the locking system be capable of supporting the weight of the packaged articles, and remain engaged during shipping and handling of the constructed carton.




One approach to provide such a stable mechanical lock assembly utilizes primary and secondary locks. The primary locks connect the ends of the carton together via the flaps, while the secondary locks function to maintain the engaged flaps in place in order to provide a “backup” locking system to prevent the primary locks from separating.




A superior locking system that overcomes many of the deficiencies of prior art locks is disclosed in U.S. Pat. No. 5,443,203 to Sutherland, which describes a mechanical locking system that does not require secondary male locking tabs to extend beyond the end edges of the blank, but which system effectively locks the tabs in place and resists withdrawal of the tabs. Yet, neither this mechanical locking system, nor other prior art systems, incorporate the ability to adjust to the variation in size of the bottles contained by the carton. That is, prior art carton blanks are stamped for a particular sized bottle. Variations in bottle size or out of round bottles necessitate a new carton to accommodate the change.




It would be advantageous to provide a variable mechanical locking system that can adjust for bottle growth or out of round bottles. This type of assembly would allow a single carton to contain a range of different bottle sizes. The present invention and its preferred embodiments provide such variable locking, while they also provide a superior flap engagement assembly.




SUMMARY OF THE INVENTION




Briefly described, in a preferred form, the objects of this invention are achieved by providing both primary and secondary lock systems. The primary lock system allows for container growth or out of round containers in the carton. The primary lock system incorporates two primary locks of different sizes located in the carton's outer bottom panel flap so that at least one of these locks will engage with the female sloped lock ledge of the carton's inner bottom panel flap. Both of these primary locks will be engaged when the containers are of normal size. If the containers are oversized or out of round, then only the larger of the primary locks will be engaged.




The primary locks of this invention are secured in the engaged position by the provision of a secondary lock system that prevents the withdrawal of the primary male locks. A secondary male lock is located in the inner bottom panel flap and connected to the panel by a fold line spaced from the end edge of the flap. An intermediate fold line divides the secondary male lock into an outer portion that extends through a secondary female lock opening in the outer bottom panel flap when the carton is locked. The female lock opening has an edge of a retainer tab that assists in holding the secondary male lock in position. This retainer tab flap prevents the withdrawal of the secondary male lock, which maintains the primary lock system in locked condition.




Primary locking of the carton includes the engagement of at least one primary lock with the novel female sloped lock ledge that forms one end of the primary female lock tab aperture in the inner bottom panel flap. This configuration allows for product growth or out of round products contained in the carton. A carton for containing six (6) containers usually has three (3) sets of two (2) primary male locks, three (3) corresponding primary female lock tab apertures, three (3) secondary male locks and three (3) corresponding secondary female lock openings.




It is an object of the present invention to provide variable carton lock assemblies that are capable of a range of adjustment, yet throughout adjustment, the lock assemblies remain locked. These lock assemblies secure the inner and outer bottom panel flaps of the carton together without the use of glue and the like.




It is a further object of the present invention to provide at least one of the lock assemblies that is self adjusting to allow for container growth or out of round containers, and yet remain in the locked position at all times.




These and other objects, features, and advantages of the present invention will become more apparent upon reading the following specification in conjunction with the accompanying drawing figures.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a perspective view of a preferred carton in a set up condition and containing bottles, which carton incorporates the variable locking features of the present invention.





FIG. 2

is a plan view of a blank from which the carton of

FIG. 1

is formed;





FIG. 3

is a plan view of the side panel and inner bottom panel flap of the blank of

FIG. 2

;





FIG. 4

is a perspective view of a secondary male lock and a primary female lock tab aperture of the present locking assembly according to a preferred embodiment;





FIG. 5

is a plan view of the side panel and outer bottom panel flap of the blank of

FIG. 2

;





FIG. 6

is a pictorial view of the bottom of a preferred carton, with the bottles removed for the purpose of clarity, demonstrating the first phase of the formation of the bottom panel;





FIG. 7

is a pictorial view similar to that of

FIG. 6

but showing the bottom panel flaps at a next intermediate stage of bottom panel formation;





FIG. 8

is a schematic view of the overlapping relationship of the inner and outer bottom panel flaps when two primary locks engage the female sloped lock ledge of the present invention.





FIG. 9

is a schematic view of the overlapping relationship of the inner and outer bottom panel flaps when only one of two primary locks engages the female sloped lock ledge of the present invention.





FIG. 10

is a partial pictorial view illustrating a secondary male lock in position to be inserted into a secondary female lock opening;





FIG. 11

is an enlarged transverse sectional view of

FIG. 10

just prior to secondary male lock insertion into secondary female lock ledge opening;





FIG. 12

is a partial pictorial view similar to that of

FIG. 10

, but illustrating the secondary male lock at a later intermediate position during formation of the bottom panel;





FIG. 13

is an enlarged transverse sectional view of

FIG. 12

;





FIG. 14

is a partial pictorial view similar to that of

FIG. 10

, but illustrating the secondary male lock in its fully inserted position; and





FIG. 15

is an enlarged transverse sectional view of FIG.


14


.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS




The present invention is intended primarily for use with wrap-around cartons containing bottles of the types used to contain soft drinks, beer and the like. A typical example of such a bottle has a generally cylindrical body with an upper portion and a bottom, a tapering shoulder smoothly continuous with the upper portion of the body, and a neck formed on the shoulder having a smaller diameter than the body. This conventional bottle B also has a neck flange projecting outwardly from the neck, and a cap attached to the upper end of the neck flange.




A constructed wrap-around carton


10


is illustrated in

FIG. 1

containing six beverage bottles B arranged in two rows of three each. The bottles B are packaged in the wrap-around carton


10


that is illustrated in blank form in FIG.


2


. The blank is formed from a foldable sheet material, such as paperboard. The carton


10


preferably is comprised of upper side panels


12


, lower side panels


14


and top panel


16


. Finger gripping apertures


22


and


24


, preferably formed by folding finger grip tabs


26


and


28


, are formed in the top panel


16


for the purpose of holding the carton


10


. Alternatively, finger gripping apertures


22


and


24


may be formed upon original die stamping of the carton


10


, wherein tabs


26


and


28


are removed at that time.




The carton


10


further comprises bottle neck openings


32


to permit the extension of a portion of both the neck of the bottle B and the bottle cap outside the body of the carton


10


. The carton


10


also includes heel restraining assemblies


34


adjacent the bottom panel, and the bottom panel is comprised of overlapping flaps


42


and


44


.




It will be understood by those in the art that the preferable carton


10


is symmetrical about a horizontal line of bisection, as viewed when

FIG. 2

is rotated lengthwise. This symmetry aids in the efficient production of the present carton. The carton need not have such symmetry, although it is preferred. As shown, the blank is rectangular in shape and includes straight edges, which also makes for an efficient layout of the blanks in a web from which the blanks are cut.




Referring now to

FIG. 2

, the top panel


16


is foldably joined to upper side panels


12


by fold lines


52


. Fold lines


52


are interrupted by bottle neck openings


32


. Upper side panels


12


are in turn foldably joined to lower side panels


14


by fold lines


54


. Flaps


42


,


44


are foldably joined to lower side panels


14


by fold lines


56


. Fold lines


56


are interrupted by the heel restraining assemblies


34


.




Referring specifically to FIGS.


2


-


4


, the inner bottom panel flap


42


includes secondary male locks


92


, one located opposite each heel restraining assembly


34


, and connected to the inner bottom panel flap


42


by fold line


94


. First and second tab cutouts


96


,


98


are located to either side of the secondary male locks


92


. Upon lifting lock


92


about fold line


94


, cutouts


96


,


98


merge into an integral primary female lock tab aperture


100


, shown in FIG.


4


. The outermost end of aperture


100


is formed by an offset lock ledge, or female sloped lock ledge,


102


. The slope of offset lock ledge


102


provides the present locking systems with a range of varying locking positions when ledge


102


is in engagement with first or second primary male locks of outer bottom panel flap


44


, described below.




As shown in

FIG. 3

, the main body of each secondary male lock


92


is formed by slits


104


,


106


extending outwardly from the ends of the fold line


94


, and transverse slit


108


. Slit


108


forms the middle portion of offset lock ledge


102


. Slits


104


,


106


, fold line


94


and offset lock ledge


102


bound aperture


100


when tab


92


is lifted, as illustrated in FIG.


4


. Secondary male lock


92


is divided into two portions by fold line


112


. The lock portion


114


of the secondary male lock


92


extends outwardly of the fold line


112


ends at slit


108


of offset lock ledge


102


.




As shown in

FIGS. 2 and 5

, the outer bottom panel flap


44


includes a locking panel section


60


connected to the main body of the flap


44


by a fold line


46


. Locking panel section


60


can be divided into primary lock panel sections


61


by slits


63


. Preferably, the number of primary lock panel sections


61


equals the number of heel restraining assemblies


34


, and each primary lock panel section


61


is of an equal size and shape. The slits


63


between the primary lock panel sections


61


permit small adjustments in the carton size. The bottle size may vary between primary lock panel sections


61


which enables each lock panel section to adjust to the size of the bottles immediately above the primary lock panel section


61


. Interrupting the fold line


46


opposite each heel restraining assembly


34


are spaced slits


62


, each slit


62


forming first and second primary locks


64


,


66


.




Located in the locking panel section


60


opposite each set of first and second primary locks


64


,


66


are slits


68


, each of which includes an outwardly extending accurate portion


72


forming a small retainer tab


74


. The slits


68


form secondary female lock openings which function in conjunction with the secondary male locks


92


as explained in more detail below. Fold lines


76


are outwardly spaced from the slits


68


, and the ends of the fold lines


76


and the slits


68


are connected by transverse slits


78


, which extend slightly beyond the slits


68


. This arrangement forms retaining flaps


82


adjacent the slits


68


.




The locking systems of the present invention as described include both a primary locking system and a secondary locking system. The primary locking system is the locking arrangement between the first and second primary locks


64


,


66


of primary lock panel sections


61


, and the female sloped lock ledge


102


forming an end of primary female lock tab aperture


100


. The secondary locking system is the locking arrangement between the secondary female lock openings (slit


68


), and the secondary male locks


92


.




The wrap-around carton


10


of

FIG. 1

is formed by moving the top panel


16


of the blank so that a portion of the necks of a group of bottles B extend up through the bottle neck openings


32


. The blank is pulled tight about the bottles B and the bottom panel flaps


42


,


44


are overlapped. The primary lock panel sections


61


of locking panel section


60


and the secondary male locks


92


of inner bottom panel flap


42


are then folded back as shown in

FIG. 6

(which omits the bottles B for the purpose of clarity), after which the primary lock panel sections


61


are folded down into final position as shown in FIG.


7


. Either or both first and second primary locks


64


,


66


are placed into primary female lock tab aperture


100


in proximity to offset lock ledge


102


. As primary lock panel sections


61


are folded down, one or both of the first and second primary locks


64


,


66


engage the offset lock ledge


102


, and in their final position are located beneath the inner bottom panel flap


42


as viewed in

FIGS. 6 and 7

.





FIG. 8

illustrates both first and second primary locks


64


,


66


tucked under inner bottom flap


42


. This would be possible when, for example, bottles B are neither too large nor out of round. If bottles B necessitate that the bottom panel of the carton


10


be wider to contain bottles B, flaps


42


,


44


can move in opposite directions, as referenced by arrows A, thus widening the bottom panel. Yet, the primary locking system of the present invention will remain locked even if lock


66


disengages offset lock ledge


102


, as shown in

FIG. 9

, as lock


64


remains tucked under offset lock ledge


102


because lock


64


extends further than lock


66


.




It will be understood by those in the art that while slit


62


is shown in

FIG. 5

forming two locking tabs, slit


62


can form more than two locking tabs, each providing another range of locking positions.





FIGS. 8 and 9

also illustrate the novel aspect of providing the carton


10


with a offset lock ledge


102


, thus enabling the bottom panel to vary in a range of widths and still remain locked. Further, this variability does not require a new blank design each time the bottle size changes within the range of bottom panel widths provided by the offset lock ledge


102


. Additionally, the variability of bottom panel sizes does not interfere with the locking relationship of bottom flaps


42


,


44


.




Since offset lock ledge


102


is sloped, and since the size of the bottom panel is defined by the engagement between locks


64


,


66


and offset lock ledge


102


, it is apparent that the size of the bottom panel will vary according to the location of engagement of locks


64


,


66


along the length of offset lock ledge


102


.

FIGS. 3 and 8

illustrate a representative embodiment of offset lock ledge


102


as related to the end of inner bottom panel


42


opposite fold line


56


. The distance between offset lock ledge


102


and the end of panel


42


varies between the distances X and Y. Although offset lock ledge


102


is depicted with a constant slope, it will be understood that this need not be the case. Generally, the bottom panel of carton


10


can vary in size by the approximate distance of Y-X. Depending on where one or both of the first and second primary locks


64


,


66


engage offset, or sloped, lock ledge


102


along its length, the bottom panel can adjust between a range that is determined mainly by the difference in distances X and Y, being the ends of the offset lock ledge


102


.




Further, the carton


10


is self-adjusting, as locking tabs


64


,


66


will shift along the length of offset lock ledge


102


in the direction of arrows B or C when the carton


10


with bottles B is raised by top panel


16


.




Thus, the present invention can accommodate a range of sizes of bottles B, without the need to modify the blank of the carton


10


. The varying lengths of locks


64


,


66


, as well as the sloping offset lock ledge


102


, provide the range of bottom panel sizes.




The secondary locking system is shown in FIGS.


10


-


15


. As illustrated in

FIGS. 10 and 11

, the secondary male locks


92


are pivoted forward about the fold lines


94


and their outer portion


114


is folded about the fold line


112


to position the end of the outer portion


114


over the retaining flaps


82


of the secondary female lock openings adjacent the retainer tabs


74


. The secondary male locks


92


are then pushed toward the interior of the carton


10


, causing the flaps


82


to slightly pivot about their fold lines


76


to permit the angular entry of the outer portions


114


into the space created between the retaining flaps


82


and the edge formed by slits


68


. The transverse slits


78


allow adjacent portions of the locking panel section


60


to yield slightly to permit continued downward passage of the outer portion


114


of secondary male locks


92


. The relationship of the various locking elements to each other during this intermediate phase of the locking process is illustrated in

FIGS. 12 and 13

.




Continued movement of the secondary male locks


92


results in the outer portions


114


being fully inserted into the secondary lock openings as shown in

FIGS. 14 and 15

. During movement of the outer portions


114


of the secondary male locks


92


through the secondary lock openings, the angle between the outer portions


114


and the bottom panel flaps


42


,


44


progresses toward a right angle. This can be seen by comparing

FIGS. 11

,


13


and


15


. The contact between the retaining flaps


82


and the outer portions


114


continually biases the outer portions


114


during their movement through the secondary locking openings toward the edges formed by the slits


68


. As a result, the outer portions


114


contact and slide past the retaining tabs


74


. When relative movement between the secondary locking tab portions


114


and the retainer tabs


74


brings the fold line


112


in proximity to tabs


74


, the secondary locking of the locking system of the present invention is established. At the same time, the secondary male locks


92


can slide along the length of slit


68


, in step with any sliding of locks


64


,


66


along offset lock ledge


102


. The fold line


112


can incorporate a knife cut


113


, shown in

FIG. 3

, which would enable tab


74


to insert through cut


113


.




It will be understood that flap


42


need not incorporate apertures


100


, but only needs offset lock ledge


102


(being a slit cut in panel


42


), to lock the primary locking subsystem of the carton


10


.




While the locking system of the present invention has been described, below is the preferred embodiment of further elements of the carton


10


.




The heels of the contained bottles B are restrained from movement by the provision of heel restraining assemblies


34


of the carton


10


, or any other suitable means for restraining the heels of the bottles from falling out of the open ends of the carton


10


. It is particularly important to restrain the outside bottles from movement as they in turn will restrain the movement of the inner bottles in the carton


10


. A preferred type of heel restraining assembly


34


is illustrated in FIG.


3


. Heel doors


122


are provided in the bottom of each lower side panel


14


and extend into the corresponding inner and outer bottom panel flaps


42


,


44


through fold lines


56


. These doors open inwardly during the erection of the carton


10


from a cut line


124


between each set of heel doors. These doors are hinged to the panels and flaps by fold lines


126


. These fold lines


126


permit the heel doors


122


of the carton


10


to be swung inwardly during erection. This permits each bottle B to be nested between a set of adjacent heel doors


122


of each heel restraining assembly


34


. This facilitates holding each bottle B in proper position, as illustrated in FIG.


1


. More importantly, these doors tend to restrain tearing around the heel apertures that are formed by these doors. Without these doors


122


there would only be cuts that could easily be torn. Further, these doors provide a flexible buffer against which the heel of the bottle can abut without tearing the carton panel surrounding the heel restraining aperture.




Accurate cut lines


130


may be formed at the top of each set of doors to permit the carton to be stretched more tightly over the heels of the bottles. Perpendicular cut lines


132


may also be provided to reduce the stress on the paperboard around the heel of the bottle. The door opening effect allows a relatively large portion of the heel of the bottles to be inserted into the aperture formed by the doors' opening, thereby enabling a relatively strong pack to tighten while minimizing the risk of tearing. As it is important to tighten the carton


10


tightly around the bottles, tightening apertures


140


are provided as extensions into the bottom flaps of the apertures formed by heel doors


122


. The tightening apertures


140


allow mechanical tightening fingers to enter and tighten the carton during erection.




While the invention has been disclosed in its preferred forms, it will be apparent to those skilled in the art that many modifications, additions, and deletions can be made therein without departing from the spirit and scope of the invention and its equivalents as set forth in the following claims.



Claims
  • 1. A wrap-around article carton for carrying articles, comprising:a. a top panel, opposite side panels and a bottom panel; b. the bottom panel having inner and outer panel flaps, each panel flap having sides, a portion of the outer panel flap overlapping a portion of the inner panel flap; c. the inner panel flap having at least one offset lock ledge with a length that slopes towards one side, the lock ledge formed by an opening cut in the inner panel flap; d. the outer panel flap having at least one primary lock for each offset lock ledge, formed by a slit cut in the outer panel flap, the primary lock having a shorter length than the offset lock ledge; and e. at least one of the primary locks extending through the offset lock ledge along the length of the lock ledge into the carton so as to lock the carton.
  • 2. The carton of claim 1, wherein each offset lock ledge of the inner panel flap forms an end of a primary female lock tab aperture.
  • 3. The carton of claim 1, wherein the outer panel flap comprises at least one set of two primary locks of different sizes, with the combined lengths of the two primary locks being shorter than the length of the offset lock ledge so that at least one of the primary locks of each set secures the carton.
  • 4. The carton of claim 3, wherein the primary locks extend through the offset lock ledge along a distance of the length of the offset lock ledge, and into the carton.
  • 5. The carton of claim 1, wherein each article has a heel, the carton further comprising heel retaining assemblies to retain the heels of the articles.
  • 6. The carton of claim 5, wherein each heel retaining assembly comprises:a. a set of heel doors attached to the side panels of the carton by fold lines; and b. accurate cut lines formed at the top of the set of heel doors.
  • 7. The carton of claim 5 having three spaced apart offset lock ledges, three spaced apart corresponding primary locks, and three heel retaining assemblies in each respective panel flap.
  • 8. A wrap-around article carton for carrying articles, comprising:a. a top panel, opposite side panels and a bottom panel; b. the bottom panel having inner and outer panel flaps, each panel flap having end edges and sides, a portion of the outer panel flap overlapping a portion of the inner panel flap; c. the inner panel flap having at least one offset lock ledge with a length that slopes towards one side, the offset lock ledge forming an end of a primary female lock tab aperture, the inner panel flap also having at least one secondary male lock connected thereto by a fold line spaced from the end edge of the inner panel flap, the secondary male lock extending a length equal to the distance across the lock tab aperture; d. the outer panel flap having at least one primary lock for each offset lock edge formed by a slit cut in the outer panel flap, the combined length of the primary locks being shorter than the length for the corresponding lock ledge, the outer panel also having a secondary female lock opening spaced from the end edge of the outer panel flap, one edge of the lock opening being comprised of an edge of a retaining flap connected to the outer panel flap along a fold line located between the secondary female lock opening and the end edge of the outer panel flap; e. each primary lock extending through the offset lock ledge along the length of the lock ledge, and into the carton as to lock the carton; and f. a portion of each secondary male lock overlapping an end portion of the outer panel flap, and another portion of the secondary male lock extending through the secondary female lock opening in the outer panel flap so as to secure the carton.
  • 9. The carton of claim 8, wherein each secondary male lock includes an intermediate fold line dividing the male lock and delineating a base portion and an outer portion of the secondary male lock, and wherein the base portion of each secondary male lock overlaps an end portion of the outer panel flap, and the outer portion of the secondary male lock extends through the secondary female lock opening in the outer panel flap.
  • 10. The carton of claim 9, wherein the outer panel flap (d) has at least one set of two primary locks of different sizes, with the combined lengths of the two primary locks being shorter than the length of the corresponding offset lock ledge so that at least one of the primary locks of each set secures the carton.
  • 11. The carton of claim 8, wherein there are three (3) sets of primary locks with each set having two (2) primary locks of different sizes and a corresponding set of three (3) primary offset lock ledges, three (3) secondary male locks and three (3) corresponding secondary female lock openings.
  • 12. A panel in an article carton comprising:a. inner and outer panel flaps, each panel flap having end edges and sides, a portion of the outer panel flap overlapping a portion of the inner panel flap; b. the inner panel flap having at least one offset lock ledge with a length that slopes towards one side, the offset lock ledge forming an end of a primary female lock tab aperture, the inner panel flap also having at least one secondary male lock connected thereto by a fold line spaced from the end edge of the inner panel flap, the secondary male lock extending a length equal to the distance across the lock tab aperture; c. the outer panel flap having at least one primary lock for each offset lock edge formed by a slit cut in the outer panel flap, the combined length of the primary locks being shorter than the length for the corresponding lock ledge, the outer panel also having a secondary female lock opening spaced from the end edge of the outer panel flap, one edge of the lock opening being comprised of an edge of a retaining flap connected to the outer panel flap along a fold line located between the secondary female lock opening and the end edge of the outer panel flap; d. each primary lock extending through the offset lock ledge along the length of the lock ledge, and into the carton as to lock the carton; and e. a portion of each secondary male lock overlapping an end portion of the outer panel flap, and another portion of the secondary male lock extending through the secondary female lock opening in the outer panel flap so as to secure the carton.
  • 13. The panel of claim 12, wherein each secondary male lock includes an intermediate fold line dividing the male lock and delineating a base portion and an outer portion of the secondary male lock, and wherein the base portion of each secondary male lock overlaps an end portion of the outer panel flap, and the outer portion of the secondary male lock extends through the secondary female lock opening in the outer panel flap.
  • 14. The panel of claim 13, wherein the outer panel flap (c) has at least one set of two primary locks of different sizes, with the combined lengths of the two primary locks being shorter than the length of the corresponding offset lock ledge so that at least one of the primary locks of each set secures the carton.
  • 15. The panel of claim 12, wherein there is at least three (3) sets of primary locks with each set having two (2) primary locks of different sizes and a corresponding set of three (3) primary offset lock ledges, three (3) secondary male locks and three (3) corresponding secondary female lock openings.
  • 16. A blank for forming a wrap-around carton, comprising a generally rectangular sheet having ends and sides, said sheet comprising:a. at one end of the sheet an inner panel flap having at least one offset lock ledge with a length that slopes towards one side of the sheet, the offset lock ledge forming an end of a primary female lock tab aperture, the inner panel flap also having at least one secondary male lock connected thereto by a fold line spaced from the end edge of the inner panel flap, the secondary male lock extending across the lock tab aperture; b. a side panel, a top panel, and an opposite side panel foldably connected to the inner panel flap in that order; and c. a foldably interconnected outer panel flap on the other end of the sheet having at least one primary lock for each offset lock edge formed by an opening in the outer panel flap, the combined length of the primary locks being shorter than the length for the corresponding lock ledge, the outer panel also having a secondary female lock opening spaced from the end edge of the outer panel flap, one edge of the lock opening being comprised of an edge of a retaining flap connected to the outer panel flap along a fold line located between the secondary female lock opening and the end edge of the outer panel flap.
  • 17. The blank of claim 16, wherein the outer panel flap comprises at least one set of two primary locks of different sizes, with a combined lengths of the two primary locks being shorter than the length of the offset lock ledge.
  • 18. The carton of claim 16, wherein there are three (3) sets of primary locks with each set having two (2) primary locks of different sizes and a corresponding set of three (3) primary offset lock ledges, three (3) secondary male locks and three (3) corresponding secondary female lock openings.
  • 19. The blank of claim 18, wherein the blank has heel retaining assemblies to retain the heel of each article.
US Referenced Citations (8)
Number Name Date Kind
3655117 Weiss Apr 1972
4611754 Sutherland Sep 1986
4815599 Schuster Mar 1989
4844328 Cooper Jul 1989
5398870 Bienaime Mar 1995
5671845 Harris Sep 1997
5682995 Sutherland Nov 1997
5975286 Oliff Nov 1999