US2936104A

US2936104A - Collapsible carton

Info

Publication number: US2936104A
Application number: US588679A
Authority: US
Inventors: Blaere William H De
Original assignee: BLOOMER BROS CO
Current assignee: BLOOMER BROS Co
Priority date: 1956-06-01
Filing date: 1956-06-01
Publication date: 1960-05-10
Anticipated expiration: 1977-05-10

Description

May 10, 1960 w. H. DE BLAERE COLLAPSIBLE CARTON 3 Sheets-Sheet 1 Filed June 1, 1956 INVENTOR, WILLIAM H. DE BLAERE HIS ATTORNEY May 10, 1960 w. H. DE BLAERE COLLAPSIBLE CARTON 3 Sheets-Sheet 2 Filed June 1, 1956 INVENTOR, WILLIAM H. DE BLAERE HIS ATTORNEY May 10, 1960 w. H. DE BLAERE 2,936,104

COLLAFSIBLE CARTON I5 Sheets-Sheet 3 Filed June 1, 1956 INVENTOR, DE BLAERE WILLIAM H.

HIS ATTORNEY United States Patent ce 2,936,104 Patented May 10, 1960 2,936,104 I COLLAPSIBLE CARTON William H. De Blaere, Newark, N.Y., assignor to Bloomer grog; Company, Newark, N.Y., a corporation of New Application June 1, 1956, Serial No. 588,679

Claims. (Cl. 229-51) This invention relates to collapsible cartons made of fibrous material, such as cardboard, for packaging ice cream and other frozen comestibles, and the like. As the result of a recent invention, such cartons have been provided with bottom flaps so constructed as to be automatically unfolded and extended by manipulation of the side walls. This automatic bottom construction has been combined with a side opening pull flap and has resulted in a practical and useful carton, which has been widely used in this field. However, these cartons were so constructed that when the side opening flap was pulled and the closure wall opened, the bottom flaps were moved out of engagement and the carton became partially unfolded and unfit for further use.

One object of the present invention is to provide an improved carton of the general character described, but so constructed as to remain substantially intact when opened for partial removal of the contents, and thus, kept in condition for being reclosed for further preservation of the remaining contents.

Another object is to provide a carton of the above nature which is provided with positive means for holding the opposite ends of the carton erect, particularly the bottom end, when the closure wall is opened.

Another object is to provide a carton having the above advantages in which the means for holding the bottom of the carton erect is integral with the remaining portions of the carton and does not require any additional stock.

Another object is to provide a carton of the above nature which is so constructed as to be readily manufactured, conveniently erected for filling and conveniently opened by the consumer, as described below.

A further object is to afford a carton having the above advantages in a form capable of being readily manufactured in quantity lots, by known machines and at relatively low cost.

To these and other ends the invention resides in certain improvements and combinations of parts, all as will be hereinafter more fully described, the novel features being pointed out in the claims at the end of the specification.

In the drawings:

Fig. 1 is a plan view of a one-piece blank cut and scored ready for folding to form a carton embodying the present invention;

Fig. 2 is a similar view with the bottom flap portions folded over and glue applied;

Fig. 3 is an edge view of the blank as seen'from the bottom in Fig. 2, but with the outer wall portions partially folded over toward glued position;

'Fig. 4 is similar to Fig. 3, butwith the parts glued together and the carton in collapsed condition;

Figs. 5 and 6 are top plan views from the inside of the carton in progressive positions of erecting for filling;

Figs. 7 and 8 are bottom plan views from the outside of the carton in progressive positions of erection for filling substantially corresponding to Figs. 5 and 6, respectively;

Fig. 9 is a perspective view of the carton in erected position with the top flaps open for filling;

Fig. 10 is a perspective view of the carton showing the same erected, filled and closed;

Fig. 11 is a perspective view of the carton as viewed from the opposite end in Fig. 10, showing the carton after being opened for'removal of a portion of the contents;.

Fig. 12 is an enlarged, fragmentary perspective view of the inside of the bottom end of the carton showing the locking arrangement between inner flaps, and

Fig. 13 is an enlarged, fragmentary, perspective view of the inside of the bottom end of the carton showing a slightly modified construction of the locking arrangement between the inner flaps.

The preferred embodiment of the present invention, herein disclosed by way of illustration, is preferably made of a onepiece blank such as shown in Fig. l of the drawings, cut and scored to form front, intermediate, rear and closure walls, 20, 22, 24 and 26, respectively, separated by parallel scored

fold lines

28, 30 and 32, as shown. A securing strip 34 is foldably connected with closure Wall 26 along a fold line 36 which is parallel to

fold lines

28, 30 and 32, as shown in Fig. 1. Securing strip 34 is adapted to be detachably glued to the free edge portion of the opposite or front wall 20- when the walls are folded over as hereafter described.

Closure wall 26 is preferably provided adjacent the bottom of the carton with a line of weakening which com--- prises a slit 38 extending partially through the materialf. forming the closure wall, for any known means whereby' the material forming the closure wall is weakened forcontrolling the direction and extent of the tearing actiom .of the closure wall. Slit 38 which is partially cut through:

the closure wallon the under surface thereof (upper sur-- face as viewed in Fig. 1), extends substantially trans-- versely across the closure wall from the front to the rear edge thereof, and is spaced slightly upwardly from the fold line between the closure wall and its attached bottonn flap, as shown in Fig. 1, for a purpose hereafter described.

Front wall 20 preferably has an undulating slit 40 extending thereacross adjacent the upper free edge there of, as shown in Figs. 1 and 11.. Slit 40 extends only partially through the structure forming the front wall andl provides a weakened outer surface area 42 to aid in the opening of the carton and to prevent peeling of front wall 20 when the carton is opened. Front wall 20 has a notch 44 formed in the upper edge thereof adjacent the bottom end of the carton, for a purpose hereafter described. Securing strip 34 is preferably provided with a slit 46 adjacent its line of fold with closure wall 26 to prevent an extension of surface peeling of securing strip 34 into the closure wall when the carton is opened.

Side walls

20, 22, 24 and 26 are provided with

top closure flaps

48, 50, 52 and 54, respectively, which are fold-ably connected therewith along a score line 56. Flap may be completely folded and glued by the manufacr will fold inwardly inside the carton when the carton side;

further use.

walls are collapsed, and will automatically move outwardly to their erected positions normal to the side walls of the carton, when the carton is erected. A carton of the above-general nature was disclosed in the prior patent to William H. Inman and Raynor M. Holmes, No. 2,655,304. However, in the above patented construction the bottom of the carton separated when the closure wall was opened and thereby made the carton unfit for However, I have devised a construction, as shown in the present application, whereby a carton may be constructed, having an automatic bottom with the above advantages, but which is also provided with positive means for holding the bottom of the carton in erected position, when the closure wall is opened.

More specifically, in the present construction I provide certain of the bottom flaps with positive interengaging means which, when the carton is moved to erected position by the user, interengage and securely lock the flaps in erected position thereby holding the bottom of the carton erect as the closure wall is subsequently opened. To this end, I preferably provide four bottom closure members or flaps which are foldably connected with the carton side walls along a score line 62. A pair of inwardly folding

outer bottom flaps

64 and 66 are located opposite one another and preferably are foldably connected to front and

rear walls

20 and 24, respectively.

Flaps

64 and 66 are provided with

score lines

68 and 70, respectively, extending diagonally across and separating each of them into two portions, as at 72 and 74 (Fig. 1) so that each may be folded over itself and over the side wall to which it is connected, as hereafter described.

. 4 area 94 on flap 64, and to a similar restricted area 96 on flap 66. Glue is likewise applied in a narrow band 98 on securing strip 34 adjacent its line of fold, leaving an unglued outer portion 100 to provide a free pull tab which is preferably extended and formed with an extension 102 which is foldably connected with securing strip 34 along a diagonally extending score line 104, as shown in Figs. 1 and 2.

In the further folding and gluing of the blank, front wall 20 and flap 64 are folded over intermediate wall 22 and its attached bottom flap 80. This brings glue portion 94 of flap 64 into contact with the outer surface of flap 80. Closure wall 26 and attached flap 82 are folded over rear wall 24 and fiap 66, thereby bringing flap 82 into engagement with glue area 96 of flap 66 and bringing glue portion 98 of securing strip 34 into engagement with weakened area 42 of front wall 20. Notch 44 in front wall 20 accommodates member 88 and prevents an overlapping of front wall 20 by flap 82. This completes the folding and gluing of the carton in compact, collapsed condition shown in Fig. 4, ready for storage and shipment to ice cream dispensers and the like.

Flaps

64 and 80, and

flaps

66 and 82, when secured together as above, form two interengaging bottom closure sections, each comprising an inner and outer bottom flap. When it is desired to erect the carton for filling, the bottom closure sections are quickly snapped to their erected positions by inward pressure against opposite edges 106 The outer free edges of

flaps

64 and 66 have the irregular shape shown in the drawings, including

notches

76 and 78, respectively, for engagement with each other in the erectedposition of the carton.

Intermediate wall 22 has a substantially rectangular bottom flap 80 foldably connected therewith along fold line 62. Closure wall 26 has a substantially trapezoidal flap 82 foldably connected therewith, as shown in Fig. l. Flap 80 has a portion cut away along the side edge adjacent flap 64 for forming an inwardly tapering notch 84 (Fig. 1) having an abutment 86 at thewide end thereof. Abutment 86 may slope inwardly or may be somewhat concave, as shown in Fig. 1. The abutment at the inner end of notch 84 may also extend in a direction parallel to fold

lines

56 and 62, as shown at 86' in Fig. 13.

Flap 82 has a part or member 88 projecting beyond its normal right hand edge (as viewed in Fig 1). Part 88 extends beyond the projection of the longitudinal axis of score line 36, and is formed at the base thereof with a line of bending 90 (Fig. 1) which preferably comprises a series of short slits cut into the under surface of the flap (as viewed in Fig. 1) for allowing member 88 to bend relative to the remaining portionof the flap. Member 88 is formed at the inner end with a locking shoulder 92. While I have shown locking shoulder 92 as extending in a direction substantially parallel with

fold lines

56 and 62, it will be understood that shoulder 92 might be concave or might be shallower at the inner end thereof adiacent line of fold 90. That is, since shoulder 92 cooperates with abutment 86 or 86' for holding the 'lower end of the carton erect when the closure wall is opened, as hereafter described, it will be understood that both the shoulder and abutment are preferably shaped so that the opening action holds them in, rather than moving them out of, interengagement.

In the folding and gluing of the blank, as shown in Fig. 2, bottom flap 64 is folded on itself and folded inwardly over front wall 20, as shown. Flap 80 is folded over intermediate wall 22. Flap 66 is folded on itself and folded inwardly over rear wall 24 and flap 82 is folded over closure wall 26. In this position of the parts, glue. or other suitable adhesive is applied to a restricted and 108 (Fig. 4) which serves to shape and distend the side walls in the progressive manner shown in Figs. 5 and 6, as viewed through the open top of the container, and in Figs. 7 and8, as viewed from the bottom of the container. The separation of closure wall 26 from rear wall 24 tends to pull inwardly folded flap 66 and inner bottom flap 82 to erected positions, while the separation of front wall 20 from intermediate wall 22 pulls inwardly folded flap 64 and inner bottom flap to erected positions. Flap 64 is provided with a small projecting part or tab which engages the outer surface of inner bottom flap 82 to initiate proper erection of the bottom flaps in the desired sequential order. Flap 64 is provided with a second and larger projecting part or tab 112 which is located along the free edge of the inner portion 72 of flap 64 adjacent score line 68, as shown in Fig. 1. Part 112 rides along the outer surface of inner bottom flap 82 of the opposite bottom section while outer bottom flap 66 rides along the outer surface of inner bottom flap 80. The inner portion of flap 64, including part 112 rides along flap 82 beneath the outer portion of opposite bottom flap 66, while the inner portion of flap 66 rides beneath the outer portion of flap 64, as can be seen in Fig. 8. As a result, the opposite edges of

flaps

64 and 66 slide along the outer surfaces of the opposite inner bottom flaps until

flaps

64 and 66 come into interengagement, as shown in Fig. 8, with

notches

76 and 78 interengaged. Such engagement of the notches tends to limit the erecting movement of

flaps

64 and 66 with these flaps in a position normal to the walls of the carton. The erecting movement of the bottom flaps is also preferably limited by their interengagement and by the engagement of the inner bottom'flap 80 with the inside of

flaps

64 and 66 along the bottom corners of the carton.

During the movement of the bottom flaps to their erected positions, member 88 on 'flap 82 strikes against the inside surface of front wall 20. Since member 88 projects beyond the body of flap 82, member 88 makes flap 82 wider than the bottom end of the carton, and is bent upwardly toward the open end of the carton by the action of the front wall 20 in holding back against it as flap 82'moves to fully erected position. Notch 84 infla'p 80 is positioned to overlie member 88, as shown in Fig. 12, and provides clearance for member 88 to be bent upwardly towards the open end of the carton. This positions member 88 so that shoulder 92 is in lockrelation with abutment 86 of notch 84.

When closure wall 26 is opened it tends to move flap 82 upwardly in a counterclockwise direction as viewed in Fig. 12. However, this upward movement of fiap 82 is resisted by the engagement of

abutment

86 or 86 and shoulder 92, which prevents flap 82 from moving out of its erected position shown in Fig. 8. As a result, closure wall 26 may be readily separated from flap 82 along slit 38, as hereafter more fully described.

Thus, my novel construction provides a positive connection between the front and rear walls of the carton through

flaps

80 and 64, and 82 and 66, so that the bottom of the carton will remain erect when the closure wall is opened. While in Fig. 12 I have shown locking member 88 and locking notch 84 so formed that abutment 86 and shoulder 92 are slightly spaced from one another in the erected position of the carton, this is not necessary and the above members may be formed was togbe in direct engagement when the carton is in the erected position, as shown in Fig. 13. It will be understood that when I refer to locking member 88 and notch 84 as being in locking relation 1 include forming the members so that they are in direct locking engagement,

as shown in Fig. 13, or are spaced slightly apart as shown in'Fig. 12. The contents of the carton aid in holding inner bottom flap 80 in fully erected position normal to the side walls of the carton, and thus, locking member-88 and notch 84 in their proper positions. It should be noted that flap 80 is preferably the same size as the bottom end of the carton and overlies

diagonal score lines

68 and 70 for the full length thereof, thereby providing a substantially leak-proof bottom closure, and also providing a smooth interior for the bottom end of the carton.

The carton is quickly snapped to its above erected position by merely pressing on

opposite corners

106 and 108, as stated, leaving the top closure flaps in open position, as shown in Fig. 9, to receive the contents. The carton resting on its bottom, is then filled and the top closed by folding

flaps

50 and 54 down across the filling opening, in order, after which fiap 48 is folded down followed by flap 52. Tongue 60 of flap 52 is engaged in slit 58 of flap 48 to secure the closure of the top or filling opening. It will be noted that tongue 60 is on the flap of the rear wall to which the closure wall is also attached and is pointed in the direction of the closure wall so that an opening pull on the latter serves to keep the tongue in engagement with the slit to main tain the top end of the carton closed. The carton is now in the condition shown in Fig. and is ready to be delivered to the consumer.

To open the carton, it is only necessary to grasp the unglued edge of securing strip 34. For this purpose, tab or extension 102 may be readily bent relative to securing strip 34 about fold line 104. The opening of closure wall 26 is made easier by the provision of weakened area 42 on the upper free edge of front wall 20. This .weakened area not only makes it easier to break thedetachable connection between securing strip 34 and front wall 20, but it also prevents undesired surface peeling of either the front wall or securing strip. Slit 46 also prevents undesired surface peeling of closure wall 26 by preventing any peeling of securing strip 34 from extending into closure wall 26.

After securing strip 34 is detached from front wall 20, it is necessary to separate closure wall 26 from bottom flap 82 which is foldably connected therewith. I have found it is desirable to separate the above wall and flapalong a line extending transversely across the closure wall adjacent the lower or bottom end of the carton. I have found that if the carton is made of cylinder board or paper and the blank is positioned so that the fibers extend substantially transversely across the closure wall, closure wall 26 may be moved to'open position, as shown in Fig. 11, and separated from botdirection, as by means of an'upward pull on securing strip 34.- However, I have found that closure wall 26 may be more readily separated from bottom flap 82 if the closure wall is provided with a suitable line of weakening along which the tearing action may readily take place in a predetermined manner and direction.

To this end, closure wall 26 is preferably provided with a. slit 38, extending substantially transversely thereacross adjacent the lower end of the carton. Slit 38 preferably extends into closure strip 34 for a sufficient distance to intersect with slit 46. When the closure wall is opened, the tearing action moves along slit 38. Not only does slit 38 provide a line of weakening along which the tearing action may readily occur, but slit 38 przlyl ents any undesired surface peeling of the closure w When the carton is opened in the manner described above, both ends remain erect, as shown in Fig. 11. The upper end of the canton remains erect because flap 54 which is foldably connected with closure wall 26 may be moved independently of top locking flaps 48 and 52, and therefore, the opening of the closure wall does not disturb the locking action of

flaps

48 and 52. That is, although top flap 54 is held in closed position by

flaps

48 and 52 when the canton is in closed position, as shown in Fig. 10, flap 54 at the same time is held out of contact with the contents of the carton by flap 50. Therefore, when closure wall 26 is raised, flap 54 readily moves upwardly with the closure wall to its position shown in Fig. 11, while the remaining top flaps are maintained in closed position, thereby holding the upper end of the carton in shape, as shown in Fig. 11.

The lower end of the carton remains erect because of the unique construction and arrangement of the bottom flaps. Specifically, there is a positive connection between the front and rear walls of the carton independent of closure wall 26, adjacent the lower end of the carton. This connection comprises inner bottom flaps and 82 which remain inlocking engagement when closure wall 26 is opened, as described above, and outer bottom flaps 66 and 64. That is, inner bottom flap 82 is held in its erected position by the locking engagement between member '88 and notch 84. Since flap 32 is fastened to outer flap '66 by means of adhesive 96, and flap 66 is foldably connected to rear wall 24, fiap 82 is thus connected to rear wall 24. Therefore, as flap 82 remains in its normal erected position when the closure wall is opened, as shown in Fig. 11, rear wall 24 is held in its normal erected position. The above positive connection between the front and rear walls of the carton also includes inner bottom flap 80 which is in engagement with flap 82 and outer bottom flap 64 which is foldably connected to front wall 20 and is secured to flap 80 by glue area 94. As a result, flap 8'0 is con nected to the front wall of the carton. Therefore, since flap 80 has a positive connection with the front wall 20 and flap 82 has a positive connection with rear wall 24, it will be seen that the interlocking engagement between. flaps 80 and 82 holds the front and rear walls and the bottom end of the carton erect when closure wall 26 is opened.

Thus, it will be seen from the above relationship of the parts that both the top and bottom ends of the carton remain erect when closure wall 26 is detached from front wall 20 and separated from associated bottom flap 82. With the carton in its position shown in Fig. 11, the contents may be removed to the desired extent and the carton reclosed for replacing under refrigeration to preserve the residue of the contents for further consumption. This may be readily accomplished by merely inserting top flap 54 outside of top flap 50, but inside of tom'flap. 82 byexerting sufiicient force in the opening '15 strip 34 inside of front wall 20.

The invention as herein disclosed, comprises related embodiments of the inventions disclosed in thecopending applications of William H. Inman, Serial Nos. 588,731 and 588,730 filed June 1, 1956, now patents numbered 2,684,180 and 2,878,986, respectively, and certain features disclosed but not claimed herein are claimed in said copending applications. v 7

Thus, it will be seen from the above description that my invention provides a carton which may be readily and economically manufactured with the usual materials and by known methods and standard machines in compact, collapsed condition for storage or shipment to foijd dispensers. The latter may erect the carton by merely pressing on its opposite corners toerect the automatic bottom construction. Thereafter, the carton maybe easily filled at the top and closed in the usual manner until ready for delivery to the consumer. The consumer can readily open the carton to remove a portion of the contents by pulling on tab 102 so as to swing the closure wall into open position in which the contents are exposed for dipping out to the extent desired. When the carton is opened, as above, both the top and bottom ends and the side walls remain erect sothat the carton may be readily reclosed to preserve the remaining contents. The front and rear walls of the carton are held erect at each end thereof by positive interlocking connection.

In addition, it will be seen that cartons having the above advantages may be readily andeconomically manufactured with a minimum of loss. That is, the blanks as shown in Figs. 1 and 2 are so designed that there is a minimum of wastage of cardboard stock material, and these cartons require no more material than doknown cartons having automatic bottom constructions of the type that separate when the closure wall is opened. 7

Thus, my invention provides improved cartons requiring no more material than cartons heretofore made but having the additional advantage of a positive connection between the front and rear walls for holding the carton erect when the closure wall is opened.

It will thus be seen that the invention accomplishes its objects and while it has been herein disclosed by reference to the details of a preferred embodiment, it is to be understood that such disclosure is intended in an illustrative, rather than a limiting sense, as it is contemplated that various modifications in the construction and arrangement of the parts will readily occur to those skilled in the art, within the spirit of the invention and the scope of the appended claims.

I claim:

l. A collapsible carton having a self-erecting bottom comprising a blank cut, scored and folded to form foldably connected side walls and a closure wall, a detachable connection between said closure wall and the opposite side wall for securing said closure wall in closed position, said walls having top and bottom closure flaps foldably connected thereto at the opposite ,ends thereof, said bottom fiaps being arranged in pairs of opposed inner and outer flaps, each of said outer flaps being fixedly secured to the adjacent inner flapfor forming the bottom of the carton in sections, the outer flap of each section having a folding score line extending thereacross diagonally inwardly from the corner of the carton included by said section, said outer flaps being foldable inwardly about said score lines together with saidinner flaps upon relative lateral shifting of said walls to collapsed position, said bottom sections being moved to erected closed position normal to said walls by erecting movement of said walls, one of said inner bottom flaps having a locking abutment formed along one edge thereof, a locking shoulder on the other of said inner bottom flaps positioned for engagement with said abutment, in the erected position of the carton, said abutmentrand shoulder being moved into interlocking position by the erecting movement of said bottom closure sections for holding the bottom of the carton erect when the closure wall is opened, one of said outer bottom flaps overlying said abutment and shoulder when in interlocked position for preventing leakage around said abutment an'd shoul der, and locking means on two of said top closure flaps for releasably locking said top closure flaps in closed positionin the erected position of the carton, said closure wall being detachable from said opposite side wall and separable from the bottom flap connected with said closure wall for movement to open position to expose the carton contents said locking abutment and said locking shoulder holding said inner bottom flaps in erected position, each of said inner bottom flaps remaining secured to the adjacent outer bottom flap whereby said bottom sections remain intact and in erected position, said bottom sections holding said front and rear walls of the carton in erected position.

2. A collapsible carton having a self-erecting bottom comprising a blank cut, scored and. folded to form foldably connected side walls and a closure wall, a detachable connection between said closure wall and the opposite side wall for securing said closure wall in closed position, said walls having top and bottom closure flaps foldably connected thereto at the opposite ends thereof, said bottom flaps being arranged in pairs of opposed inner and outer flaps, one of said inner bottom flaps being larger than the other inner bottom flap and being innermost when the carton is in erected position, each of said outer flaps being fixedly secured to the adjacent inner flap for forming the bottom of the carton in sections, the'outer' flap of each section having a folding score line extending thereacross diagonally inwardly from the corner of-the carton included by said section, said outer flaps being foldable inwardly about said score lines together with said inner flaps upon relative lateral shifting of said walls to collapsed position, said bottom sections being moved to erected closed position normal to said walls by erecting movement of said walls, the innermost of said inner bot-- inner bottom flaps, said shoulder extending beyond an edge of its associated flap in position for engagement with the inner surface of said opposite side wall as the bot torn closure flaps are swung to erected position for movement out of the plane of said associated flap and across the plane of said abutment into locking engagementtherewith, and locking means on two of said top closure ,flaps for releasably locking said top closure flaps in closed position in the erected position of, the cartomsaid closure wall being detachable from said opposite side wall'and separable from the bottom flap connected with saidf closure wall for movement to, open position to. expose the carton contents, said locking abutment and said locking shoulder holding said inner bottom flaps in erectedposition, each of said inner bottom flaps securedto the.

adjacent outer flap whereby said bottom sections remain intact and in erected position, said bottom sections main:

taining the front and rear walls of the carton in erected position.

3. A collapsible carton having a self-erecting bottom comprising a blank cut, scored and folded to form folde ably connected side walls and a closure Wall, a detachable connection between said closure wall and the opposite side wall for securing said closure wallin closed position,

said walls having top and bottom closure flaps foldably connected thereto at the opposite ends thereof, said bot tom flaps being arranged in pairs of opposed inner and outer flaps, each of said outer flaps being secured'to the shifting of said walls to collapsed position, said bottom sections being moved to erected closed position normal to said walls by erecting movement of said walls, one of said inner bottom flaps having substantially the size and shape of the inside bottom of the carton to cover the same and having a locking abutment formed along one edge thereof, a locking shoulder on the other of said inner bottom flaps positioned for engagement with said abutment in the erected position of the carton, said abutment and shoulder being moved into interlocking position by the erecting movement of said bottom closure sections for holding the bottom end of the carton erect when the closure wall is opened, and locking means on two of said top closure flaps for releasably locking said top closure flaps in closed position in the erected position of the carton, said closure wall being formed with a line of weakening extending thereacross adjacent the bottom of the carton, said closure wall being detachable from said opposite side wall and separable along said line of weakening from the bottom flap connected with said closure wall for movement to open position to expose the carton contents with the carton in erected position.

4. A collapsible carton having a self-erecting bottom comprising a blank cut, scored and folded to form foldably connected side walls and a closure wall, a detachable connection between said closure wall and the opposite side wall for securing said closure wall in closed position, said walls having top and bottom closure flaps fold-ably connected thereto at the opposite ends thereof, said bottom flaps being arranged in pairs of opposed inner and outer flaps, one of said inner bottom flaps being larger than the other inner bottom flap and being innermost when the carton is in erected position, each of said outer flaps being fixedly secured to the adjacent inner flap for forming the bottom of the carton in sections, the outer flap of each section having a folding score line extending thereacross diagonally inwardly from the corner of the carton included by said section, said outer flaps being foldable inwardly about said score lines together with said inner flaps upon relative lateral shifting of said walls to collapsed position, said bottom sections being moved to erected closed position norm-a1 to said walls by erecting movement of said walls, the innermost of said inner bottom flaps being formed with a locking abutment along one edge thereof positioned to underlie the upper free edge of said opposite side wall when the carton is in erected position, a locking shoulder on the other of said inner bottom flaps, said shoulder extending beyond an edge of its associated flap in position for engagement with the inner surface of said opposite side wall as the bottom closure flaps are swung to erected position for movement out of the plane of said associated flap and across the plane of said abutment into locking engagement therewith, one of said outer bottom flaps overlying said bottom locking members when in interlocked position for preventing leakage therearound, and locking means on two of said top closure flaps for releasably locking said top closure flaps in closed position in the erected position of the carton, said closure wall being formed with a line of weakening extending thereacross adjacent the bottom of the carton, said closure wall being detachable from said opposite side wall and separable along said line of weakening from the bottom flap connected with said closure wall for movement to open position to expose the carton contents, said locking 10 abutment and said locking shoulder holding said inner bottom flaps in erected position, each of said inner bottom flaps secured to the adjacent outer flap whereby said bottom sections remain intact and in erected position, said bottom sections maintaining the front and rear walls of the carton in erected position.

5. A collapsible carton having a self-erecting bottom comprising a blank cut, scored and folded to form foldably connected front, intermediate rear and closure walls, a securing strip on said closure wall detachably glued to the free edge of said front wall for securing said closure wall in closed position, said walls having top and bottom closure flaps foldably connected thereto at the opposite ends thereof, said bottom flaps being arranged in pairs of opposed inner and outer flaps, said inner flaps being foldably connected with said intermediate and closure walls, one of said inner bottom flaps being larger than the other inner bottom flap and being innermost when the carton is in erected position, each of said outer flaps being fixedly secured to the adjacent inner flap for forming the bottom of the carton in sections, the outer flap of each section having a folding score line extending thereacross diagonally inwardly from the corner of the carton included by said section, said outer flaps being foldable inwardly about said score lines together with said inner flaps upon relative lateral shifting of said walls to collapsed position, said bottom sections being moved to erected closed position normal to said walls by erecting movement of said walls, the innermost of said inner bottom flaps being connected with said intermediate wall and being formed with a locking abutment along one edge thereof positioned to underlie the upper free edge of said front wall when the carton is in erected position, a locking shoulder on the inner bottom flap connected with said closure wall, said shoulder extending beyond an edge of its associated flap in position for engagement with the inner surface of the front wall as the bottom closure flaps are swung to erected position for movement out of the plane of said associated flap and across the plane of said abutment into locking engagement therewith, one of said outer bottom fiaps overlying said bottom locking members when in interlocked position for preventing leakage therearound, and locking means on two of said top closure flaps for releasably locking said top closure flaps in closed position in the erected position of the carton, said closure Wall being formed with a line of weakening extending thereacross adjacent the bottom of the carton, said closure wall being detachable from said front wall and separable along said line of weakening from the bottom flap connected with said closure wall for movement to open position to expose the carton contents, said locking abutment and said locking shoulder holding said inner bottom [flaps in erected position, each of said inner bottom flaps secured to the adjacent outer flap whereby said bottom sections remain intact and in erected position, said bottom sec tions maintaining the front and rear walls of the carton in erected position.

References Cited in the file of this patent UNITED STATES PATENTS 1,662,698 Crarner Mar. 13, 1928 2,011,232 Parks et all. Aug. 13,1935 2,655,304 Inman et al Oct. 13, 1953 2,686,629 Inman Aug. 17, 1954