US3907194A

US3907194A - Polygonal container

Info

Publication number: US3907194A
Application number: US494756A
Authority: US
Inventors: Larry C Davenport; Harold W Layne; Jon M Schwaner
Original assignee: Inland Container Corp
Current assignee: Inland Container Corp
Priority date: 1974-08-05
Filing date: 1974-08-05
Publication date: 1975-09-23
Anticipated expiration: 1992-09-23
Also published as: CA1008421A

Abstract

A polygonal container is disclosed which, in its preferred embodiment, includes a unitary lower body portion and a separable cap portion. The unitary body is made from a flat sheet of foldable material having fold lines defining side panels and integrally connected end closure flaps and web portions which are foldable to effect interlacing of the web portions and end closure flaps and establish a self-locking closed end of the container. The flat body sheet may have generally identically shaped end closure flaps and web portions on each end to establish end closures on both ends of the assembled container.

Description

United States Patent Davenport et al.

[ Sept. 23, 1975 [54] POLYGONAL CONTAINER 3.526.352 9/1970 Swett 1 o 229/41 x 2 3 J 22 T [75] Inventors: Larry C. Davenport, Indianapolis; 46 11/197 Tyne 9/4] C X Harold W. Layne, Beech Grove; Jon 4 Przmarv Examiner-Davis T. Moorhcad M. I a I f C Schwaner ndmnapohb All 0 Attorney, Agent. or FirmF1tch, Evcn, Tabm & lnd.

Luedeka [73] Assignee: Inland Container Corporation,

Indianapolis. Ind. [57] ABSTRACT [22] Filed: 1974 A polygonal container is disclosed which, in its pre {211 A N 494,75 fcrred embodiment, includes a unitary lower body portion and a separable cap portion. The unitary body is made from a flat sheet of foldable material having [52] 229/23 BT; 229/41 C; 229/39 fold lines defining side panels and integrally connected [5 l] llt. Cl. B65D 13/00; B65D 5/36 end closure p and web portions which are folduble [58] held of Search 229/23 23 4] Q to effect interlacing of the web portions and end clo- 229/39 sure flaps and establish a selflocking closed end of the container. The flat body sheet may have generally [56] References C'ted identically shaped end closure flaps and web portions UNITED STATES PATENTS on each end to establish end closures on both ends of 2.044.103 6/1936 ROSSl 229/41 UX the mbl d container. 3,()l6.l8l 1/1962 Desmond 229/39 R 3.261.533 7/1966 Repking 229/41 c x 9 Clams 7 Drawmg Flgures I V 22 I22 /24 124' m 25 5 134 I8 34 A2438? /Z6 40 2 l I30 44 01 I34 24 l 1 I 1 1 l 1 l l f I \I/ \4! I! l 1-! I l I, :L :L |y. L |1 n l I 26 I22" l I 1 .30 l 6 4. 22 g 52 1 I 1 7 4/7 2 I23 Hz/Maya [5 56 POLYGONAL CONTAINER The present invention relates generally to containers, and more particularly to a polygonal shaped container made from a foldable sheet material having a novel configuration which effects self-forming into its final container configuration when end flaps and associated connecting webs are folded into interlacing relation.

The structural strength advantages of polygonal shaped containers versus conventional four-sided containers made of comparable material are well known. For example, tests have shown that a polygonal shaped container, such as one having an octagonal transverse configuration, may exhibit as much as a 50 percent increase in stacking strength over four-sided containers.

The conventional practice in the use of polygonal shaped containers has been to employ a three-piece construction consisting of a polygonal shaped tubular body and a pair of end caps. Such conventional threepiece polygonal containers frequently exhibit disadvantages which, in general, more than offset the strength advantages gained over a foursided container. Particularly. two end caps must be preassembled. The bottom cap is typically used as a set-up fixture to hold the polygonal shaped tube or body portion in its final folded configuration. The polygonal tube or body portion must be pro-opened on its eight vertical hinge or fold lines to substantially a perfect polygonal configuration in order to fit inside the bottom cap. Prior three-piece polygonal container constructions further frequently exhibit a tendency for the tubular body to bulge at the top and bottom perimeters when filled.

Attempts have been made to overcome the last mentioned disadvantage through the provision of top and bottom flanges independently foldable about fold or hinge lines disposed between the flanges and associated side panels. The use of such individual flanges adds considerably to set-up time. Additionally, the cut or slot lines disposed between the adjacent flanges makes the hinge lines susceptible to tearing when the container is subjected to heavy internal bulk loads. Additionally, unless such flanges are of substantial length, the filled tubular body has a tendency to lift out of the bottom cap during handling, thus requiring gluing, stapling or strap fastening of the end cap to the tubular body to prevent breakage or product spillage.

In accordance with one embodiment of the present invention, a polygonal container is provided which is made of corrugated fiberboard or other suitable material in sheet form which may be die-cut to form a unitary blank from which the body portion of the container can be erected. The unitary blank has fold lines thereon which define side panels, upper end flanges, and lower end closure flaps and web portions. Folding of the lower end closure flaps along their respective fold lines to lie substantially in a plane perpendicular to the longitudinal axis of the intended container effects self-forming of the side panels of the polygonal shaped body into their intended assembled configuration. Such folding of the lower flaps and web portions forms a bottom end closure which eliminates the need for a separable end cap, the lower end closure flaps and webs serving to effect self-locking due to interlacing of the integrally connected flap and web areas. The end of the container opposite the end having the integral end closure flaps and webs thereon may have flanges foldably connected to the side panels. These flanges are inte grally interconnected in a manner such that when folded to lie in a plane normal to the longitudinal axis of the container, they resist bulging of the upper perimeter of the container. If desired, the unitary blank may have both ends identically formed to provide integral end closures on each end of the container.

One of the primary objects of the present invention is to provide a polygonal shaped container made from a novel unitary foldable blank of sheet material having fold lines defining side panels and integral end closure flaps and webs, the end closure flaps and webs being foldable to a self-locking configuration by interlacing of the end closure flaps and webs.

Another object of the present invention is to provide a container having an octagonal shaped transverse configuration defined by side panels having end closure flaps and web portions integrally connected to at least the lower ends of the side panels by fold lines in a manner to effect self-forming of the side panels into their intended assembled octagonal configuration as the end closure flaps and webs are folded into interlacing relation to form an integral end closure for the container.

Another object of the present invention is to provide a container of the type described wherein the upper end of the container, when disposed in a generally upright position, has integral top flanges interconnected by angular hinge lines so that when the top flanges are folded to lie in a plane substantially normal to the longitudinal axis of the container, the flanges resist bulging of the upper end of the container.

A feature of the present invention lies in the provision of alternate generally rectangular and triangular shaped end closure flaps on at least one end of the unitary blank from which the container is formed, the alternate end flaps being interconnected by generally trapezoidal shaped webs which are foldable with the rectangular and triangular end flaps to effect selective interlocking, and wherein the outer ends of selected of the rectangular end flaps are formed in a manner to facilitate such interlocking during manipulation to form an end closure for the container.

Further objects and advantages of the present invention, together with the organization and manner of operation thereof, will become apparent from the following detailed description of the invention when taken in conjunction with the accompanying drawings wherein like reference numerals designate like elements throughout the several views, and wherein:

FIG. 1 is a perspective view of a container constructed in accordance with the present invention, the container being shown in an assembled condition and inverted to illustrate the bottom end closure in closed position;

FIG. 2 is a plan view of a unitary blank from which the container of FIG. 1 is formed;

FIG. 3 is a partial perspective view of the container of FIG. 1 but with the bottom end closure illustrated in a partially closed position;

FIG. 4 is a plan view of a unitary blank similar to the blank of FIG. 2 but having a glue pattern formed thereon and an inner reinforcing liner secured onto the outer blank prior to folding into an assembled container configuration;

FIG. 5 is a partial perspective view of the container illustrated in FIG. 1 in an upright position to show the upper reinforcing flanges;

FIG. 6 is a plan view of a blank foldable to form an end cap for the end of the container illustrated in FIG. and

FIG. 7 is a perspective view of an end cap formed from the blank of FIG. 6.

Referring now to the drawings, and in particular to FIGS. 13, a container constructed in accordance with one embodiment of the present invention is indicated generally at 10. The container 10 includes a generally upright body portion, indicated generally at 12, and a bottom end closure, indicated generally at 14. For purposes of illustration, FIGS. 1 and 3 show the container 10 in an inverted position to more clearly illustrate the bottom end closure construction.

With reference to FIG. 2, the container 10 is formed from a foldable blank 16 of sheet material, such as corrugated fiberboard or other suitable sheet material of the desired strength, which, in its unfolded sheet form has a generally rectangular configuration thereby making the container blank readily adapted for stacking, shipping and storage without protuberanees from the stack being subjected to snagging or tearing in a manner to damage the container blanks. The foldable blank 16 may be made of single-wall, double-wall or triplewall sheet stock dependent upon the physical characteristics of the product to be packaged and the strength requirements of the container 10 as dictated by the manner of distribution and storage thereof. As will become more apparent hereinbelow, it is contemplated that, if necessary, the container 10 include a liner to increase the strength of the container for packaging purposes.

The rectangular blank 16 of sheet material from which the container 10 is constructed has upper and lower parallel edges l8 and 20, respectively. and

parallel end edges

22 and 24 which form right angles with the upper and lower edges 18 and so as to define the substantially rectangular blank 16 of sheet material. A connecting strip 26 is preferably formed integral with the side edge 22 and is foldable about a fold line 28 which coincides with the left-hand edge 22 of the blank 16. A connecting strip 30 is preferably formed integral with the right-hand edge 24 ofthe blank 16 and is foldable about a fold line 32 which coincides with the edge 24 of the blank 16.

The blank 16 has a plurality of

fold lines

34, 36. 38, 40, 42, 44 and 46 which extend between and are generally normal to the upper and lower edges 18 and 20 of the blank 16 to divide the blank 16 into a plurality of side-by-

sidc panels

48, 50, 52, 54, 56, 58, 60 and 62. When the blank 16 is folded into the container 10. the

score lines

34, 36, 38, 40, 42, 44 and 46 are considered to be longitudinal fold lines disposed parallel to the longitudinal axis of the container 10.

In the illustrated embodiment, eight side panels are established between the

fold lines

28, 34, 36, 38, 40, 42, 44 and 46 such that the assembled container 10 has a generally octagonal configuration. The

side panels

54 and 62 are disposed in opposed parallel relation, when the blank 16 is assembled into the container 10, and are of greater transverse width than the

side panels

50 and 58 which lie in parallel planes disposed perpendicular to the planes of the

side panels

54 and 62. The interme diate

side panels

48, 52, 56 and 60 form the corner panels of the container 10.

The blank 16 of sheet material has a plurality of integral end closure flaps and web element portions foldably connected to the respective side panels along a fold line 64 disposed parallel to the bottom edge 20 of the blank 16 and spaced upwardly therefrom, as considered in FIG. 2. The integral end closure flaps and web element portions, to be described, provide the selfloc king bottom end closure 14 of the container 10.

To this end, the blank 16 has a first pair of rectangular generally equal size end closure flaps 66 and 68 which are foldably connected, respectively, to the

side panels

62 and 54. A second pair of generally rectangularly shaped equal size end closure flaps 70 and 72 are foldably connected, respectively, to the

side panels

58 and 50. The end closure flaps 70 and 72 are smaller in lateral width than the end flaps 66 and 68. When the blank 16 is folded to form the container 10, the end closure flaps 66 and 68 will be connected to opposite generally

parallel side panels

62 and 54 and foldable in a direction perpendicular to the direction of fold of the end flaps 70 and 72 which will be connected to oppositely disposed

parallel side panels

58 and 50 of the container.

Four isosceles triangle shaped end flaps 74, 76, 78 and of equal size are foldably connected along their base edges, which lie on the fold line 64, to the

intermediate side panels

60, 56, 52 and 58. Each of the triangular shaped end flaps 74, 76, 78 and 80 has an apex, indieated at 74, 76, 78 and 80, respectively, disposed opposite its base edge, with the apexes of the respective triangular end flaps lying on a common line disposed parallel to and spaced upwardly from the lower edge 20 of the blank 16, as considered in FIG. 2.

Each of the triangular end flaps 74, 76, 78 and 80 is connected to the next adjacent rectangular end flaps through a trapezoidal shaped web. For example, the triangular shaped end flap 74 is connected to the adjacent rectangular end flap 66 through a web portion 82 foldable about a first fold line 46 which forms an extension of the fold line 46, and foldable about a second fold line 46" which forms one of the legs of the triangular shaped end flap 74. A slot 84 is formed in the blank 16 to extend from the lower edge 20 of the blank to the apex 74' otthe triangular flap 74, the slot 84 being disposed parallel to the fold line 46. A similar trapezoidal shaped web 86 is integrally connected between the end closure flap 70 and the triangular shaped flap 74 along fold lines 44' and 44". In similar fashion, a web 88 is foldably interconnected between the triangular shaped end flap 76 and the rectangular end flap 70 along fold lines 42' and 42", the trapezoidal configuration of web 88 being completed by a slot 90 extending from the lower edge 20 to the apex 76 of the triangular end flap 76. A trapezoidal shaped web 92 foldably interconnects the triangular shaped end flap 76 and the rectangular shaped end flap 68 along

fold lines

40 and 40". A trapezoidal shaped web 94 interconnects the triangular end flap 78 and the rectangular end flap 68 along

fold lines

38 and 38", with a slot 96 completing the trapezoidal configuration of the web 94. A trapezoidal web 98 foldably interconnects the triangular shaped end flap 78 to the rectangular shaped end flap 72 along

fold lines

36 and 36". A trapezoidal shaped web 100 foldably interconnects the triangular shaped end flap 80 to the rectangular shaped end flap 72 along

fold lines

34 and 34", with a slot 102 being formed in the blank 16 to complete the trapezoidal configuration of web 100. And lastly, a trapezoidal web 104 is foldably connected to the triangular shaped end flap 80 along a fold line 48", the major leg of the trapezoidal web 104 being the left-hand edge 22 of the blank 16.

In the illustrated embodiment, portions of the blank 16, as represented by the areas 106 and 108, maybe cut away to form beveled edges 110 and 112 on the rectangularly shaped end flap 68. A fold line 114, disposed parallel to the fold line 64, is formed on the end flap 68 to define a tongue portion 116 on the flap 68 which may be selectively'folded about the fold line 114 to assist in manipulating the end flaps and webs to form the bottom end closure 14, as will be described hereinbelow.

The upper end of the blank 16 has a plurality of integral flange portions which are foldable to lie in a plane perpendicular to the longitudinal axis of the container during assembly. and which provide reinforcement for the upper perimeter of the container to prevent bulging when the container is loaded with a bulk material, such as a particulate material. To this end, a fold line 118 is formed on the blank 16 parallel to and spaced downwardly from the upper edge 18. The fold line 118 provides a fold axis for a plurality of rectangularly shaped

upper end flanges

120, 122, 124, 126, 128, I30, I32 and 134 which are connected, respectively, to the

side panels

48, 50, 52, 54, 56, 58, 60 and 62 about the fold line 118. The noted upper end flanges 120-134 are integrally connected by triangular web portions such as indicated by 122, 124, 126, 128', 130', 132' and 134. The triangular web portion 134 is representative of the triangular webs interconnecting the adjacent upper end flanges, and is foldable about a fold line 46" which forms an upper extension of the fold line 46, and about a fold line 134". The remaining upper triangular webs 122'132' are similarly foldably connected to their adjacent upper end flanges.

It will be appreciated that a number of the blanks 16 may be shipped and stored in flat stacked relation. Because of their generally rectangular configurations, handling a stack of blanks 16 presents little possibility of damage to the blanks as might result if the blanks had one or more outwardly directed projections formed thereon which could tear and result in damage to the blanks.

When it is desired to erect a container 10 from a blank 16, the blank is folded along the fold lines 28, 32, 34, 36, 38, 40, 42, 44 and 46. At this time, a suitable adhesive may be applied to the upward facing surface of the connecting strip 30, or alternatively, to the upward facing surface of the connecting strip 26, as considered in FIG. 2, in a manner to allow the connecting strips 26 and to be adhesively secured together such that the

edges

22 and 24 of the blank 16 are in substantial abutment. It will be understood that an adhesive may be applied to selected portions of the connecting

strips

26 and 30 during initial forming of the blank 16, with the adhesive being activated or prepared for sticking contact at the time of assembly.

With reference to FIG. 3, which shows the container 10 in an inverted position with the bottom end closure 14 being partially closed, the end flaps 66 and 68 are folded downwardly substantially into a plane containing the peripheral fold line 64 which defines the lower ends of the associated side panels. The end flaps 66 and 68 are folded downwardly such that the tongue portion 116 underlies the end of the end flap 66. As the end closure flaps 66 and 68 are folded inwardly, the

adjacent webs

82,92, 94 and 104 are folded about the associated

fold lines

46, 40', 38 and 48 such that the

webs

82, 92, 94 and 104 overlie the end flaps 66 and 68. Such movement of the webs connected to the end flaps 66 and 68 causes the triangular end flaps 74, 76, 78 and 80 to be drawn downwardly toward the plane containing the fold line 64, such movement of the triangular end flaps serving to also cause the associated

webs

86, 88, 98 and 100 to be drawn inwardly such that their outer surfaces overlie the triangular end flaps 74, 76, 78 and 80. At this point, the end flaps 70 and 72 may be manually grasped and folded inwardly to complete folding of the end closure flaps and associated webs into a plane substantially perpendicular to the longitudinal axis of the resulting container. lnterlacing of the rectangular end flaps 66, 68, 70 and 72 with the triangular end flaps 74, 76, 78 and 80 and the interposed

webs

82, 86, 88, 92, 94, 98, and 104 serves to maintain the end flaps and webs in their folded conditions as shown in FIG. 1.

An adhesive, such as a suitable glue or the like, may be added to selected areas of the

webs

82, 86, 88, 92, 94, 98, I00 and 104 to assist in maintaining the bottom end closure flaps and webs in their folded positions. For example, an adhesive may be applied to the areas indicated at 136 and 138 on the lower portions of the

webs

82 and 98 such that when the

webs

82 and 98 are folded to abut the opposing surfaces of the end closure flaps 66 and 68, respectively, the

adhesive areas

136 and 138 will maintain these webs and end flaps in surface-to-surface contact.

When folding the blank 16 as described to establish the bottom end closure 14, the upper end flanges 17.0l34 and interposed webs 122'l34' may be substantially simultaneously folded into a plane containing the peripheral fold line 118. Such folding of the end flanges 134 with the associated interconnected webs l22134' maintains the end flanges in their folded positions whereby to strengthen the upper perimeter of the container 10 to resist bulging and the like.

It will be noted that the lateral widths of the

side panels

50, 54, 58 and 62, and the lateral widths of the

corner panels

48, 52, 56 and 60, are selected such that the outer edges of the

end closure panels

70 and 72 are in relatively close but spaced relation when in their folded positions, while the outer end of the closure flap 66 overlies the tongue 116 of the closure flap 68. A typical size bulk container in accordance with the described container 10 has a height of 36 inches and a transverse cross section of approximately 33 X 4] inches, with the diagonal corners ranging from about 6 to 12 inches.

FIG. 4 illustrates a blank of sheet material, indicated generally at 140, which is provided with fold lines substantially as shown for the blank 16 of FIG. 2. The blank 140 is foldable into an octagonal shaped container having substantially the same configuration as the container 10 illustrated in FIG. 1. It will be noted that the blank of sheet material 140 has a greater width to height ratio than the blank 16 illustrated in FIG. 2.

The blank 140 illustrated in FIG. 4 has a plurality of adhesive strips or lines 142 applied thereon along the longitudinal length of the blank in parallel spaced relation between the fold lines 64 and 118. In the embodiment of FIG. 4, parallel adhesive strips 142 of a suitable pressure sensitive, hot melt or wettable adhesive are formed on the blank 140. The adhesive strips 142 serve to secure an inner liner sheet 144 onto the surface of the blank 140 with an coverage, which will constitute the inner peripheral surface of the container formed from the blank 140. The inner liner 144 has a rectangular configuration which substantially conforms to the area of the blank defined within the upper and

lower fold lines

64 and 118 and the lateral end edges 22 and 24. The rectangular inner liner 144 may be made from a suitable foldable paper or fiber sheet material or a plastic sheet material having strength characteristics sufficient to provide the desired increased structural strength for a container formed from the blank 140, as compared to a container not having such a liner. In other respects, the blank 140 is substantially identical to the aforedescribed blank 16 and may be folded to form an octagonal shaped container in similar fashion to folding the blank 16 to form the container 10.

The blank 16 for forming the container 10, as considered in FIG. 2, may be provided with upper rectangular and triangular end flaps and integral webs, such as described for the lower end closure 14, in place of the upper flanges 120-134 and webs 122'134. In this manner, after the bottom end closure 14 ofa container is formed, the container may be placed in an upright position and filled as desired. The upper rectangular and triangular end flaps and integrally connected webs could then be folded into a closed position to form an upper end closure which eliminates the need for a separate cap or cover.

If it is desired to make the container 10 with the upper flange structure described and use a separate top cap or cover, a cap such as shown in FIGS. 6 and 7 may be employed. With particular reference to FIG. 6, a cap suitable for use with the container 10 is indicated generally at and is formed from a blank 152 of sheet material such as corrugated fiberboard or other suitable sheet material having the desired strength characteristics. The blank 152 has a generally rectangular configuration dependent upon the cross-sectional configuration of the container with which the cap is to be employed. The illustrated blank 152 has beveled corners 154 and has

fold lines

155, 156, 158 and 160 formed thereon which correspond in length to widths ofthc corresponding major side panels of the octagonal shaped container with which the cap 150 is to be used. The fold lines 155. 156. 158 and 160 are connected by diagonal fold lines 162 which have lengths corresponding to the widths of the

diagonal side panels

48, 52, 56 and 60 of the above described container 10. The blank 150 is severed along lines 164 to establish corner flaps 166. A double fold line 168 is provided on each of the corner flaps 166 in parallel relation to the fold lines 162 to allow the outer portion of each corner flap 166 to be folded back underneath itself such that the outermost edge of each corner flap may be tucked upwardly througha slot 170 provided adjacent and intermediate each of the diagonal fold lines 162 as is known Fold lines 172 are formed adjacent each of the corner flaps 166 as shown to establish triangular shaped locking tabs 174. When forming the cap 150 from the blank 152, peripheral marginal areas 156, 158' and are folded about the

respective fold lines

155, 156, 158 and 160 to lie in planes normal to the remaining planar area of the blank 152. The corner flaps 166 and lock tabs 174 are then folded about their respective fold lines such that the outer portion of each corner flap is wrapped about the adjacent locking tabs 174 whereafter each outer beveled edge 154 is inserted upwardly through the associated slot to lock the depending sidcs and corners in fixed folded conditions. Thereafter, the cap 150 is ready to be placed onto the upper end of a container 10.

Thus, in accordance with the present invention, an octagonal shaped container is provided which may haveboth bottom and top end closures formed integral with the intermediate octagonal shaped body portion, or the body portion and bottom end closure may be formed integral with a separable closure cap being mountable on the upper end of the container. The end closure construction includes rectangular and triangular end flaps and trapezoidal shaped interconnecting web portions which provide an interlacing of the webs and end closure flaps to effect a self-locking action which maintains the bottom end closure in its folded condition.

A feature of the container in accordance with the present invention is that the polygonal shaped body portion is self-forming into its intended configuration as the bottom end closure flaps and webs are folded into a closed position, with additional forming assistance being provided in the upper area of the container by folding of the upper end flanges.

While a preferred embodiment of the present invention has been illustrated and described, it will be understood to those skilled in the art that changes and modifications may be made therein without departing from the invention in its broader aspects. Various features of the invention are defined in the following claims.

What is claimed is:

1. A container made from a foldable blank of sheet material, said container comprising a plurality of hingedly Connected side panels defining a body portion having an octagonal transverse cross-sectional configuration, a first pair of generally rectangular end closure flaps hingedly connected to the ends of a pair of opposed side panels through fold lines, a second pair of generally rectangular end closure flaps hingedly connected to the ends of a different pair of opposed side panels through fold lines disposed in a plane containing the fold lines of said first pair of end closure flaps, said fold lines of said second pair of end closure flaps being generally perpendicular to the fold lines of said first pair of end closure flaps, an isosceles triangle shaped end flap connected to each of the remaining side panels through a fold line lying in the plane of the said fold lines of said first and second pairs of end closure flaps, and a trapezoidal shaped web portion interconnecting said first and second pairs of generally rectangular end closure flaps to the adjacent triangular shaped end flaps through fold lines, said pairs of generally rectangular end closure flaps and said web portions each having an outer edge lying on a generally straight line defining an outer edge of said blank of sheet material prior to folding, the apex of each of said triangularly shaped flaps lying on a common line parallel to and spaced from said outer edge of the blank, said end closure flaps, triangular end flaps and web portions being foldable to form a closed end of the container lying in a plane substantially perpendicular to the longitudinal axis of the container with said web portions and triangular end flaps serving to interlace with said pairs of rectangular end flaps to self-lock said end flaps into their folded positions.

2. A container as defined in claim 1 wherein said pairs of generally rectangular end closure flaps have lengths, considered longitudinally of said blank prior to folding, such that the outer ends of selected ones of the opposed rectangular end closure flaps overlap when in their folded positions.

3. A container as defined in claim 1 wherein at least one of said web portions has an adhesive thereon to secure the adhesive surface of the web portion to the op-' posing surface of one of said rectangular end closure flaps when in their folded positions.

4. A container as defined in claim 1 wherein the side panels associated with one of said pairs of rectangular end closure flaps are greater in width than the width of the side panels associated with the other of said pairs of rectangular end closure flaps, said side panels intermediate the side panels associated with said first and second pairs of end closure flaps being of generally equal width less than the widths of the remaining side panels.

5. A container as defined in claim 1 including a liner made from a foldable sheet material and secured to the interior surfaces of said side panels.

6. A container as defined in claim 2 wherein selected ones of said trapezoidal web portions are cutaway adjacent one of said rectangular end closure flaps to facilitate manipulation of said one of said end closure flaps to a position underlying its opposed rectangular end closure flap when in folded positions.

7. An integral blank of foldable material for forming a polygonal shaped container, said blank comprising a plurality of side-by-side generally rectangular side .panels defined by longitudinally extending, spaced, parallel fold lines, a connecting strip foldably connected along the outer longitudinal edge of a side panel forming one of the outer edge side panels of said blank, generally rectangular end closure flaps hingedly connected to selected common ends of alternate ones of said side panels, each of said rectangular end closure flaps having a width substantially equal to the width of its associated side panel, an isosceles triangle shaped end closure flap hingedly connected to an end of each of said side panels intermediate said side panels having said rectangular end closure flaps foldably connected thereto, said triangular end flaps being on the same end of said blank as said rectangular end flaps and each having a base side connected to its associated side panel through a fold line extending the full width of the associated side panel, the apex of each of said triangular end flaps terminating at a point spaced from a straight line containing the outermost edges of said rectangular end flaps, a trapezoidal shaped web interconnecting each of said rectangular end closure flaps to the laterally adjacent triangular shaped end flaps along fold lines disposed along the lateral longitudinally extending edges of the rectangular end flaps and along the equal length legs of said isosceles triangle shaped end flaps, at least one of said rectangular end flaps having a foldable tongue portion for insertion into a slot defined by an opposing rectangular end flap and its adjacent connected trapezoidal web portions when folded in underlying relation to said opposing rectangular end flap whereby to retain said tongue portion in connected relation with said opposing rectangular end flap when in their folded positions.

8. A blank of foldable material as defined in claim 7 including a reinforcing liner secured to the surfaces of said side panels which will form the interior surface of a container made from the blank, said liner having a generally rectangular configuration and being of substantially equal area to the interior surface areas of said connected side panels.

9. A blank of foldable material as defined in claim 7 wherein said rectangular end closure flaps, said triangular shaped end flaps and said trapezoidal shaped webs are connected to said side panels adjacent common first end portions thereof, and including additional end flanges hingedly connected to the ends of said side panels opposite said first end portions, said end flanges being laterally interconnected by integral triangular shaped webs such that upon folding said blank into a container, said flanges and triangular webs may be folded into a plane substantially perpendicular to the longitudinal axis of the resulting container to increase the strength of the upper perimeter of the container.

l l= l l

Claims

3. A container as defined in claim 1 wherein at least one of said web portions has an adhesive thereon to secure the adhesive surface of the web portion to the opposing surface of one of said rectangular end closure flaps when in their folded positions.

7. An integral blank of foldable material for forming a polygonal shaped container, said blank comprising a plurality of side-by-side generally rectangular side panels defined by longitudinally extending, spaced, parallel fold lines, a connecting strip foldably connected along the outer longitudinal edge of a side panel forming one of the outer edge side panels of said blank, generally rectangular end closure flaps hingedly connected to selected common ends of alternate ones of said side panels, each of said rectangular end closure flaps having a width substantially equal to the width of its associated side panel, an isosceles triangle shaped end closure flap hingedly connected to an end of each of said side panels intermediate said side panels having said rectangular end closure flaps foldably connected thereto, said triangular end flaps being on the same end of said blank as said rectangular end flaps and each having a base side connected to its associated side panel through a fold line extending the full width of the associated side panel, the apex of each of said triangular end flaps termiNating at a point spaced from a straight line containing the outermost edges of said rectangular end flaps, a trapezoidal shaped web interconnecting each of said rectangular end closure flaps to the laterally adjacent triangular shaped end flaps along fold lines disposed along the lateral longitudinally extending edges of the rectangular end flaps and along the equal length legs of said isosceles triangle shaped end flaps, at least one of said rectangular end flaps having a foldable tongue portion for insertion into a slot defined by an opposing rectangular end flap and its adjacent connected trapezoidal web portions when folded in underlying relation to said opposing rectangular end flap whereby to retain said tongue portion in connected relation with said opposing rectangular end flap when in their folded positions.