US2884180A

US2884180A - Collapsible carton

Info

Publication number: US2884180A
Application number: US588731A
Authority: US
Inventors: William H Inman
Original assignee: BLOOMER BROS CO
Current assignee: BLOOMER BROS Co
Priority date: 1956-06-01
Filing date: 1956-06-01
Publication date: 1959-04-28
Anticipated expiration: 1976-04-28

Description

W. H. lNMAN COLLAPSIBLE; CARTON April 28, 1959 4 Sheets-Sheet 1 Filed June 1. 1956 I I v I.

INVENTOR, WILLIAM H. INMAN HIS ATTORNEY April 28, 195 9 w. H. INMAN COLLAPSIBLE CARTON 4' SheetsSheet 2 Filed June 1. 1956 INVENTOR,

WILLIAM H. INMAN HIS ATTORNEYI April 28, 1959 w. H. [mm 2,884,180

' COLLAPSIBLE CARTON Filed June 1. 1956 4 Sheets-Sheet s mwszvroa, WILLIAM H. INMAN HIS .ATTORNEY April 28, 1959 w. H. lNMAN 2,884,180

COLLAPSIBLE CARTON Filed June 1. 1956 4 Sheets-Sheet 4 2 3'6 g 29o 284 3l8 Q 3 \g\( INVENTOR, f1 5-1 1 WILLIAM H. iNMAN HIS ATTORNEY United States Patent co LArsIBLE CARTON William H. Inman, Newark, N.Y., assignor to Bloomer Bros. Company, Newark, N.Y., a corporation of New York Application June 1, 1956, Serial No. 588,731 4 Claims. (Cl. 22941) 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 unfiit 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 beng 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, byknown 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, but with 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 erection 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 the carton;

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

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; i V l i Fig. 12 is a fragmentary, plan view similar to Fig. l of a blank cut and scored ready for folding to form a carton having a slightly modified construction;

Fig.' 13 is a top plan View of the inside of the carton made fromthe blank shown in Fig. 12, showng the carton in fully erected position with a portion of the inner flap broken away for purposes of illustration;

Fig. 14 is a fragmentary, plan view similar to Fig. 1 of a blank cut and scored ready for folding to form a carton having a further modified construction, and

Fig. 15 is a 'top plan view of the inside of the carton made from the blank shown in Fig. 14, showing the carton fully erected and with part of the inner bottom flap 'removed for purposes of illustration.

The preferred embodiment of the present invention, herein disclosed by way of illustration, is preferably made of a one-piece blank such as shown in Fig. 1 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 shownl "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. l. 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 may comprise, singly or in combination, a line of perforations 38, a'single slit 40 extending partially through the material forming the closure wall', or any known means whereby the material forming the closure wall is weakenedfor controlling the direction and extent of the tearing action of the closure 'wall. Line of perforations 38 preferably comprises a series of spaced short slits which may extend partially or completely through the material forming the'closure wall, as shown in Fig. 1, and this line of perforations 38 extends substantially transversely across the closure wall adjacent to the fold line between the closure wall and its attached bottom flap for allowing separation of the closure wall from said bottom flap, as hereafter described. Slit 40 which is partially cut through the closure wall on the under surface thereof (upper surface as viewed in Fig. 1) extends substantially transversely across the closure wall from the front to the rear edge thereof, and is spaced slightly upwardly from the line of perforations, as shown in Fig. l, and for a purpose'hereafter'described.

Front wall 20 preferably has an undulating slit .42 extending thereacross adjacent the upper free edge thereof, as shown in Figs. 1 and 11. Slit 42 extends only partially through the structure forming front wall 20 and provides a weakened surface area 44 to aid in the opening of the carton and to prevent "peeling of front wall 20 when the carton is opened. 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 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, 51), 52 and 54, respectively, which are foldably connected therewith along a score line 56. Flap 48 is formed with a slit 58 to receive altongue or hook 60 on 'flap' 52 for securing these top flaps 'in 'p'osit ion for 3 closing the top of the carton. The carton is erected and filled through the top, after which the top flaps are folded over and locked in position for closing the carton. When the carton is opened, as hereafter described, thetop flaps preferably remain in locked position for holding the top of the carton erect.

My carton is also preferably provided with bottom closure flaps which are so constructed that the carton may be completely folded and glued by the manufacturer and then shipped in collapsed, flat position to the user who may erect it by merely applying pressure to the opposite corners of the collapsed carton, as hereafter described. The bottom flaps are so constructed that they will fold inwardly inside the carton when the carton side 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 my prior joint patent with 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 made the carton unfit for further use. 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 when 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.

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 erected position of the carton. Flap 64 also has a T-shaped projecting part or tongue 80 formed along the free edge of the inner portion of the flap adjacent score line 68, as shown in Fig. 1, and for a purpose hereafter described.

Intermediate wall 22 has a substantially rectangular bottom flap 82 foldably connected therewith along line 62, as shown in Fig. 1. Closure wall 26 has a substantially trapezoidal flap 84 foldably connected therewith, as shown in Fig. 1. Flap 84 is preferably provided with an arcuate slit 86 which terminates at each end in one of a pair of substantially straight slits 88 which lie along intersecting lines, as shown in Fig. 1.

Slits

86 and 88 extend through the material forming flap 84 for forming a locking aperture or passageway shown generally at 90 which is adapted to cooperate with and lock tongue 80 as the tongue is moved through the aperture during the erecting movement of the carton, as hereafter more fully described. One of slits 88 extends substantially transversely of flap 84 towards fold line 62 while the other of slits 88 extends substantially longitudinally of the flap toward the tapered end of the flap, as shown in Fig. 1. Thus, slits 88 are so positioned that when the bottom of the canton is moved to erected position, the slits are closer together at their ends which are first engaged by tongue as it moves across flap 84.

Slits

88 and 86 form therebetween an unsevered flap or gate 91 (Fig. 1) which may be readily pressed inwardly when tongue 80 engages it, for allowing the tongue to move through aperture 90.

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 82 is folded over intermediate wall 22. Flap 66 is folded on itself and folded inwardly over rear wall 24, as shown, and flap 84 is folded over closure wall 26. In this position of the parts, glue or other suitable adhesive is applied to a restricted area 92 on flap 64, and to a similar restricted area 94 on flap 66. Glue is likewise applied in a narrow band 96 on securing strip 34 adjacent its line of fold, leaving an unglued outer portion 98 to provide a free pull tab which is preferably extended and formed with an extension 100, which is foldably connected with securing strip 34 along a diagonally extending score line 102, 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 82. This brings glue portion 92 of flap 64 into contact with the outer surface of flap 82. Closure wall 26 and attached flap 84 are folded over rear wall 24 and flap 66, thereby bringing flap 84 into engagement with glue area 94 of flap 66, and bringing glue portion 96 of securing strip 34 into engagement with weakened portion 44 of front wall 20. 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 82, and flaps 66 and 84, 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 104 and 106 (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 and 8, 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 84 to erected positions, while the separation of front wall 20 from intermediate wall 22 pulls inwardly folded flap 64 and inner bottom flap 82 to erected positions. Flap 64 rides along the outer surface of inner bottom flap 84 of the opposite bottom section while outer bottom flap 66 rides along the outer surface of inner bottom flap 82. The inner portion of flap 64, including tongue 80, rides along flap 84 beneath the outer portion of the opposite outer bottom flap 66, while the inner portion of flap 66 rides beneath the outer portion of flap 64 until

notches

76 and 78 move into inter-engagement. This engagement of the notches limits the erecting movement of flaps in a position normal to the side walls of the carton. The erecting movement of the flaps is also preferably limited by the engagement of inner bottom flap 82 with the inside of

flaps

64 and 66 along the bottom corners of the carton.

As the inner portion of flap 64 is moved along inner flap 84 beneath the outer portion of flap 66, tongue 80 asserts a force against inner flap 84 and tends to hold back on gate portion 91 and swings the same out of the plane of flap 84 inwardly towards the top of the carton. This action opens up aperture formed by

slits

86 and 88, so that tongue 80 may readily pass through the aperture as the bottom of the carton moves to fully erected position as shown in Figs. 6 and 8. Once tongue 80 has fully passed through aperture 90, it cannot be withdrawn from the aperture without tearing and mutilating either the tongue or flap 84. As a result, once the bottom of the carton has been erected, there is then a positive connection between the front wall of the carton and the rear wall through

flaps

64, 84 and 66 and the bottom of the carton will remain erected when the closure wall is subsequently opened as hereafter described. It should be noted that flap 82 is substantially the same size as the bottom end of the carton and overlies

slits

86 and 88 for the full length thereof, as well as

diagonal score lines

68 and 70, thereby providing a substantially leakproof 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

104 and 106, 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 flap 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 maintain the top end of the carton closed. The carton is now in the condition shown in Fig. 10, 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 100 may be readily bent relative to securing strip 34 about fold line 102. The opening of closure wall 26 is made easier by the provision of weakened area 44 on the upper free edge of front wall 20. This weakened area not only makes it easier to break the detachable con nection 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 84 which is foldably connected therewith. I have found it is desirable to separate the above wall and flap along 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 bottom flap 84 by exerting suflicient force in the opening direction, 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 84 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 line of perforations 38 or slit 40, or both, extending substantially transversely thereacross adjacent the lower end of the carton. I have also found that while the tearing action may be controlled by means of either line of perforations 38 or by slit 40, the tearing action is easier and more readily controlled if the closure wall is provided with both perforations 38 and slit 40. Starting at the front lower corner of closure wall 26, line of perforations 38 preferably extends rearwardly for a short distance substantially coincident with the fold line between the closure wall and bottom flap 84. Thereafter, line of perforations 38 extends upwardly for a short distance, and then extends rearwardly across the closure wall substantially parallel with the fold line separating the closure Wall and bottom flap 84. Slit 40 also extends substantially transversely across the closure wall, but is spaced upwardly from the bottom of the carton and upwardly from perforations 38, as shown in Fig. 1. Slit 40 not only limits any upward tearing of the closure wall at an angle to the line of perforations, but slit 40 also prevents any undesired peeling of the closure wall which might result from the opening action. In addition, slit 40 may serve as either a supplementary line of separation for the closure wall or as a substitute line of separation. That is, the closure wall may separate along slit 40 instead of perforations 38, or it may separate partially along the line of perforations and partially along slit 40.

Regardless of the exact line of separation of closure wall 26 from inner bottom flap 84, both ends of the carton remain erect when the carton is in open position, as shown in Fig. 11. The upper end of the carton remains erect because fiap 54 which is foldably connected with closure wall 26, may move 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 carton is in closed position, as shown in Fig. 10, fiap 54 is at the same time 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 inwardly folding flap 64 which is attached to the front wall of the carton, inner bottom flap 84 which is attached to closure wall 26 and glued to flap 66, and outer bottom flap 66 which is attached to rear wall 24-. This connection also includes tongue which, as described above and as can be seen in Fig. 6, has passed through aperture formed by

slits

86 and 88 in bottom flap 84. Tongue 80 is adapted to cooperate with and lock in the margins of aperture 90 and is preferably formed with a somewhat pointed end or head portion 108 (Fig. l) to facilitate the entry of the tongue in aperture 90. Tongue 80 comprises a narrow neck portion 110 which connects head 108 with inner portion 72 of bottom flap 64. The opposite sides of head 108 form locking shoulders 112 which when tongue 80 has passed through aperture 90, engage the margins of the aperture and prevent the tongue from moving outwardly through the aperture, thereby locking together

bottom flaps

64 and 84. As a result, flaps 64 and 84 and, through flap 84, flap 66, are securely locked together in such a manner that they will remain in locked engagement when closure wall 26 is opened. That is, as closure wall 26 is opened and separated from flap 84, it tends to lift flap 84 upwardly in a clockwise direction as viewed in Figs. 8 and 11, counterclockwise direction as viewed in Fig. 6. This lifting action on flap 84 causes a limited movement of flap 84 relative to flap 64, which serves to draw tongue 80 into tight locking engagement with the mangins of aperture 90. Specifically, one or both of shoulders 112 of tongue 80 will be drawn into engagement with the margins of slits 88 which converge towards one another in the direction of movement of tongue 80 during the above opening action, as shown in Figs. 1 and 2. As a result, tongue 108 is drawn downwardly against the margins of slits 88, but cannot pass out therethrongh because the tongue is greater in width than the distance between slits 88 adjacent their inner ends. Thus, the front, rear and intermediate Walls remain in their erected positions and the top and bottom ends of the carton remain erect when closure wall 26 is opened, as above.

The contents of the carton may now be readily removed by dipping 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 flap 59, but inside of locking flaps 4% and 52 and then swinging closure wall 26 downwardly to its closed position. If desired, the carton may be more tightly reclosed by inserting securing strip 34 inside of front wall 20.

In Fi s. 12 and 13 I have shown a slightly modified construction in which the locking means on the bottom flap is slightly different from that of the carton shown in Figs. 11l. The carton shown in Figs. 12 and 13 also differs in that the line of perforations which extends across the cover, preferably extends in a straight line which is inclined slightly upwardly towards the rear of the canon as shown in Fig. 12. In all other respects, the modified carton is identical to the construction shown in Figs. 111. The elements of the modified carton construction are indicated by reference characters which are 100 units higher than the reference characters indicating the same or similar parts of the carton construction shown in Figs. 1l1.

As can be seen in Figs. 12 and 13, tongue 180 which is integral with inwardly folding bottom flap 164 preferably has a hemispherically shaped head portion 2198. Flap 184 is similar in shape to flap 84, but the slits in flap 184- which form aperture 196 for the reception of tongue 1811 are different from those shown earlier in connection with flap 84.

Flap 184 is preferably provided with a T-shaped slit comprising a base 186 and a vertical portion 188, and an undulating slit 214 which is intersected at substantially its midpoint by slit 188.

Slits

186, 188 and 214 form an aperture or passageway 19% in flap 184 through which tongue 18% may pass when the carton is swung to erected position in the manner described earlier in connection with the carton shown in Figs. 1-11. As shown in Fig. 13, tongue 180 projects through flap 184 and serves to lock together flaps 164 and 184. Since flap 134- is glued to flap 166 which is attached to rear wall 124, this connection extends from the front wall of the carton to the rear wall and holds the bottom end of the carton erect when closure wall 126 is opened, in the same manner as described earlier in connection with the carton shown in Figs. 11 1.

The modified carton is folded and glued in the same manner as described earlier and may be shipped and packed in flat condition. The carton may be readily opened by merely exerting pressure on the opposite corners of the collapsed carton. During erection, the bottom flaps automatically move toward fully erected position substantially normal to the side walls of the carton. Tongue 180 moves through aperture 1% and firmly locks the bottom flaps in erected position, in the manner described earlier. Thereafter, the carton may be easily filled at the top, and closed in the usual manner, ready for delivery to the consumer. The consumer may readily open the carton for removing the contents by dipping. Securing strip 13 -1 may be detached from front wall 126, closure wall 126 separated from bottom flap 184 and the closure wall and attached top flap readily moved to their open positions corresponding to the positions of closure wall 26 and flap in Fig. 11.

In Figs. 14 and 15 I have shown a second modified construction in which the locking means between the bottom sections is slightly different from that shown in Figs. 111 or in Figs. 12 and 13. In addition, the line of weakening extending across the closure wall comprises only a slit cut partially through the closure wall along the under surface thereof. In all other respects, the modified carton is identical to the construction shown in Figs. 1-11. The elements of the modified carton construction shown in Figs. 14 and 15 are indicated by reference characters which are 200 units higher than the reference characters indicating the same or similar parts of the carton construction shown in Figs. 1-11.

As can be seen in Figs. 14 and 15 tongue 28%) which is integral with inwardly folding flap 264 is preferably hemispherical in shape, and comprises merely a head portion 3418. A short slit 316 extends from one side 318 of head portion 30% substantially midway through the head, as shown in Fig. 14. Slit 316 allows side 3118 of head 3% to be bent out of the plane of the remaining portion of the head and out of the plane of the inner portion 272 of flap 264 for a purpose hereafter described. Flap 283 is preferably provided with a series of irregularly shaped slits 286 (Fig. 14) which form, inter alia, a shoulder 3219 (Fig. 1.4) and an aperture or passageway 290 through which tongue 2% passes during the erection of the carton.

The modified carton may be completely folded and glued by the manufacturer, shipped and packed in flat condition to the user who may then readily erect the carton by merely applying pressure on the opposite corners of the collapsed carton, all in the same manner as that described earlier. During erection, the bottom closure flaps automatically move to their fully erected positions substantially normal to the side walls of the carton. Specifically, tongue 2% rides along the outer surface of inner flap 284 and holds back on the right end of flap 284 (as viewed in Fig. 14) thereby opening up aperture 2% for the reception of the tongue. The bottom flaps continue towards their erected positions until tongue 2819 has passed through aperture 296 and the flaps are in their positions shown in Fig. 15.

As shown in Fig. 15, tongue 280 extends through passageway 2% in the erected position of the carton. As a major portion of flap 264 lies outside of flap 284, the free side 318 of head 3118 is bent out of the plane of the remaining portion of the head and out of the plane of flap 264, and thus, is in position to be engaged by shoulder 321) formed by slit 286. In this position, bottom flaps 264 and 284 are securely locked together. The opening action imparted to closure wall 226 tends to lift flap 284 relative to flap 264. However, this lifting movement of flap 284 is prevented by the engagement between shoulder 320 and side portion 318 of tongue 3138. As a result, the lifting action applied to closure wall 226 through securing strip 234 serves to separate the closure wall from fiap 284, thereby allowing the carton to be opened with the bottom flaps remaining in fully erected position, in a manner similar to that described above. Thus, it will be seen that the second modified carton has the same advantages of construction and operation as the cartons described earlier and further description thereof is unnecessary.

Thus, it will be seen from the above descriptions that my invention provides cartons 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 food dispensf's. The latter may erect the cartons by merely pressing on their opposite corners to erect the automatic bottom constructions. Thereafter the cartons may be easily filled at the top, and closed in the usual manner until ready for delivery to the consumer. The consumer can readily open the cartons by swinging the closure wall to open position in which the contents are exposed and may be readily dipped out to the extent desired. However, in all of the cartons described above, the top and bottom ends of the carton remain erect thereby holding the front and rear walls of the carton erect when the closure wall is opened, thus maintaining the carton in condition for further use and replacement under refrigeration.

In addition, it will be seen that cartons having the above advantages may be readily and economically manufactured with a minimum of loss. That is, the blanks as shown in Figs. 1, 12 and 14 are so designed that there is a minimum of wastage of cardboard stock material and these cartons require no more material than do known cartons having automatic bottom constructions of the type which separate when the closure wall is opened.

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

The invention, as herein disclosed, comprises related embodiments of the invention disclosed in my copending patent application, Serial No. 588,730, filed June 1, 1956, and the copending patent application of Wiiliam H. De Blaere, Serial No. 588,679, filed June 1, 1956, and certain features disclosed but not claimed herein are claimed in said copending applications.

It will thus be seen that the invention accomplishes its objects and While it has been herein disclosed by reference to the details of preferred embodiments, 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 or" 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:

1. 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, each of said outer flaps being 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 sections, 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 located on opposite sides of a hinge connection between adjacent side walls and on opposite sides of said detachable connection, said bottom sections being moved to erected closed position normal to said walls by erecting movement of said walls, a locking tongue on one flap of one of said bottom sections, one of the flaps of the other of said sections being formed with a plurality of slits for forming a locking aperture, said tongue being moved into said aperture during the erecting movement of the bottom sections for locking engagement with the margin of said aperture for holding the bottom of the carton erect when said 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 detachable from said opposite side wall and separable from the bottom fiap connected with said closure wall for movement to open position to expose the carton contents with the carton in erected position.

2. A collapsible carton having a self-erecting bottom as specified in claim 1 in which said tongue is on the outer member of one of said bottom sections and said locking slits are formed in the inner member of the other of said bottom sections.

3. 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 foidably connected thereto at the opposite ends thereof, said bottom flaps being arranged in pairs of opposed inner and outer flaps, each of said outer flaps being secured to the adjacent inner fiap 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 sections being located on opposite sides of a hinge connection between adjacent side walls and on opposite sides of said detachable connection, said bottom sections being moved to erected closed position normal to said walls by erecting movement of said walls, a locking tongue on one flap of one of said bottom sections, one of the flaps of the other of said sections being formed with a plurality of slits for forming a locking aperture, said tongue being moved into said aperture during the erecting movement of the bottom sections for locking engagement with the margin of said aperture for holding the bottom of the carton in erect position when said closure wall is opened, the innermost of said inner flaps overlying said interengaged locking means for preventing leakage around said locking means, 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 said side walls in erected position.

4. A collapsible carton having a self-erecting bottom as specified in claim 3 in which said locking tongue is formed with a head portion having a shoulder along one edge thereof, said shoulder engaging the margin of said locking aperture when said carton is in erected position for locking said bottom sections together and holding the bottom end of said carton erect when said closure wall is opened.

References Cited in the file of this patent UNITED STATES PATENTS 2,326,417 Ullrich Aug. 10, 1943 2,686,629 Inman Aug. 17, 1954 FOREIGN PATENTS 731,708 Great Britain June 15, 1955