US2978162A

US2978162A - Molded pulp carton

Info

Publication number: US2978162A
Application number: US792017A
Authority: US
Inventors: Harry E Lambert
Original assignee: Packaging Corp of America
Current assignee: Packaging Corp of America
Priority date: 1959-02-09
Filing date: 1959-02-09
Publication date: 1961-04-04
Anticipated expiration: 1978-04-04
Also published as: GB889936A

Description

April 4, 1961 2,978,162

H. E. LAMBERT MOLDED PULP CARTON Filed Feb. 9, 1959 2 Sheets-Sheet 1 @mwmm 2mm: 7

April 4, 1961 H. E. LAMBERT MOLDED PULP CARTON Filed Feb. 9, 1959 United States Patent j:

MOLDED PULP CARTON Harry E. Lambert, Gary, Ind., assignor to Packaging Corporation of America, a corporation of Delaware FiletlFeb. 9, 1959, Ser. No. 792,017 13 Claims. (Cl. 229-25) The present invention relates to an improved type of molded pulp carton and has especial reference to molded pulp egg cartons of the elongated type used in the packaging of eggs, of which the two-by-six car-ton is one ex- 'ample.

Egg cartons of the type mentioned are extensively used in the packaging of eggs. Frequently the filled cartons are stacked one on top of the other, either .during the shipment thereof in the so-called standard egg cases, for display and storage purposes in stores, and for other purposes. One form of such carton comprises two sections, bottom and top, hinged along one margin. It is preferable that only the bottom section be provided with cells to receive the eggs and that the upper wall of the top section be formed primarily of a fiat panel or panels. Such construction facilitates the stacking of the cartons and also provides broad surfaces on which advertising indicia can conveniently be impressed.

Customers at times desire but one-half the number of eggs which the entire carton contains, and in certain prior cartons the construction is such that the carton can be divided transversely into two sections.

In prior constructions the cartons of this type, when comprised of but two sections, have been relatively weak, particularly in the cover section, and this has resulted in the breaking of eggs at times.

in some prior constructions more than two sections have been provided in an attempt to provide a more rigid construction. However, such constructions increase the cost, increase the size so that it is not possible to pack the required number in a standard egg case, and are other objectionable.

'One of the objects of the present invention is to provide an egg carton construction which can be produced at reasonable cost and which will rigidity the carton,

particularly the cover section, in such manner as to prevent the breakage of eggs when the filled cartons are stacked as in shipping or storage and handled in the channels of trade.

Another object of the invention is to provide an egg carton of this type wherein the structure is such that it is feasible to mold the same from the usual pulp stock, all portions being so disposed as to provide the requisite draft angles.

Still another object of the invention is to provide an egg carton construction which, while provided with a transverse depression at the middle, which will facilitate dividing the elongated carton into two sections each containing one-half the total number of eggs, when divided will assure a considerable portion at each end of each divided section as a wrap-around sufficient fully to protect the eggs at each end of each section from the likelihood of inadvertently being displaced from the carton.

Again it is an object of the invention to provide an elongated-type egg carton adapted to be divided transversely to form two or more cartons, each with a fractional part of the total number of eggs and which shall Patented Apr. 4, 1951 be so constructed that even though the filled carton be lifted by gripping entirely at one end, the longitudinal rigidity will be such as to prevent collapse of the carton with the consequent danger of egg loss. or damage.

Other objects of the invention will be clear from. the following specification and by reference to the accompanying drawings illustrating a preferred embodiment and inwhich:

Fig. 1 is a front elevational view of a carton embodying the invention;

Fig. 2 is a top plan view;

Fig. 3 is a view in end elevation;

Fig. 4 is a plan view depicting the carton of Fig. 1 in open position, being the form in which it leaves the molding machine;

Fig. 5 is a transverse vertical sectional view on the line 55 of Fig. 4 viewed in the direction of the arrows;

Fig. 6 is a view of the carton as divided along the line 66 of Fig. 1; and

Fig. 7 is a longitudinal sectional view of the cover section along the line 77 of Fig. 4.

As shown, the carton is designed to hold one dozen eggs in the form of two rows of six eggs each. Hence, the carton is of elongated shape. The carton which is formed of molded pulp stock comprises a body having a lower section or bottom 10 and an upper section or top 11, the sections being united along one margin by an integral hinge 12 which permits the top to be folded over the bottom.

The bottom section 10 is provided with a flap 13 along its front margin, which is hinged at 14 to the bottom and is thereby adapted to be folded from the plane shown in Fig. 5 to the locking position inside the front wall of the top section 11, when the carton is in closed position.

The front wall 15 of the top section is provided With a plurality of openings 16 adapted to receive projections 17 on the flap 13, when the carton is in closed position, then serving to hold the top and bottom sections against accidental separation.

By reference to Figs. 1 and 6, particularly, it will be observed that the upper marginal portion 18 of the locking flap 13 terminates well below the underside of the panels 2fl-20 of the top or cover 11 and also below the transverse cross wall portion 21 at the center of the carton where the carton is adapted to be divided. As will be explained later by this construction, there is no likelihood of the upper marginal portion of the locking flap preventing the full engagement of the marginal peripheral portions of cover and bottom sections, as well as other parts of cover and bottom sections which are designed for supporting engagement one with the other. The bottom section It) is provided with a plurality of egg cells formed by a central row of hollow upstanding posts 25. These posts may vary in construction, those shown being by way of illustration and not by way of specific limitation. However, the arangement is such that there is one post 25C which is disposed centrally' of the carton bottom, both longitudinally and transversely. As will be seen shortly, this post coacts to pro vide support for a hollow formation in the cover when the cover is folded to closed position.

The cover central construction The cover section 11 is provided with a central transverse recess 30 formed by the depending wall portions 3131 which portions terminate in a transverse wall of special shape. Thus, the transverse wall comprises portions 3232A which, at their outer ends, merge with front and rear central cover planar wall portions 33-34 respectively, the latter being extensions of the adjacent planar wall portions 35-36 of the front and rear walls of the top or cover section.

The planar portions 33-34 being in the plane of the front and rear walls of the cover impart great strength to the carton longitudinally so that there is no likelihood of the carton bending or flexing even though it be packed with eggs liftedby gripping entirely at one end, which, is sometimes done in handling the cartons. I The transverse recess in the center of the cover is bottomed by the outer portions 3232A which, at their outer ends, merge with the upper margins of the front and rear cover wall portions 33--34, thence extend inwardly and downwardly where they merge with portions 40-41, the latter extending more abruptly downwardly and inwardly to terminate in a portion 42, which, in the closed condition of the carton, engages the top portion 2ST of the central post C of the bottom section.

As is perhaps best shown in Figs. 1, 2, 3, and 6 the depending wall portions of the cover section, which form the upright wall portions of the central transverse recess, LI

comprise, in the closed condition of the carton, central downwardly and inwardly extending portions til-41 and outer

curved portions

52, 53, 54, and 55', the latter merging at their inner margins into the planar portions "40-41, and at their outer margins into the upper planar portions of the front and rear walls of the top or cover section.

The cover end construction As is perhaps best shown in Figs. 2, 4, and 7 the ends of the cover section are formed generally like the construction at the transverse center portion. Since each end is alike, a description of one will suffice for both. Centrally, there is, in the closed position, a downwardly and outwardly extending planar portion 60, bordered front and rear by curved portions 6162, the latter merging into the planar portions of the front and rear cover walls respectively.

As is best shown in Figs. 4 and 7, the end marginal portions of the flange portion of the cover are provided with offset portions 63-64, which engage the area 65- 66 respectively at the ends of the bottom section when the cover is folded into closed vposition.

Divisional feature In order to facilitate the division of the carton into two parts'both the cover and bottom sections and the locking flap are weakened along the broken line 70. It Will be seen that the line 70 extends transversely of the cover and bottom section midway of the transverse recess in the cover and also extends throughout the planar

central portions

33 and 34 of the front and rear walls respectively. While the carton can be broken into two parts along this weakened line, nevertheless, the carton is longitudinally of suflicient rigidity to prevent premature 01' accidental rupture along this line. It will be noted that the front and rear central

planar wall portions

33 and ,34, respectively, extend upwardly from the general plane on which the cover hinges more than halfway. This construction also permits a substantial central portion 18C of the locking flap to be provided without at the same time interfering with the seating of the cover flange and other portions on the adjacent bottom marginal portions.

This arrangement, together with the central construction in which the middle upstanding post 25C of the bottom section supportingly engages the depending central portion 42 of the cover when the carton is in closed con- ,dition, provides the optimum of support and strength with the very minimum of material.

Another advantage of the carton construction herein disclosed is that even though there is a transverse recess which facilitates the division of the carton into two parts and provides for supporting contact of the bottom section post and a part of the cover, the arrangement is such that 'the locking flap has suflicient strength to withstand the stresses encountered in folding it into locking position. This is so whether the flap be folded up by hand or by mechanical devices, in which operations the flap is sometimes forced into locking position by engagement with one end only.

Also, when the carton is divided, each section fully protects the eggs which remain therein.

Thus the several conflicting requirements have been resolved in a construction which avoids objections inherent in prior art constructions and which can be readily molded from pulp stock.

At the same time the structure is such that large eggs can be adequately accommodated, and yet the over-all size of the carton is such as to permit, if desired, the packing of thirty dozen eggs in a standard egg case.

I claim:

1. A molded pulp egg carton comprising a cover section and a bottom section integrally connected by a hinge along one side margin thereof, said bottom section being defined by an upwardly extending wall structure comprising side wall and end wall portions and provided with a plurality of contiguous egg-receiving cells successively arranged in row formation, said cell-forming structure including at least one row of hollow upstanding posts extending between opposite end wall portions, said cover section comprising a plurality of panel portions defined by downwardly extending side and end wall portions and a pair of spaced downwardly extending transverse wall portions intermediate the end wall portions, said cover side wall portions each including a bridge part intermediate its end, extending upwardly from the lower margins of the side wall portion and terminating in a plane substantially below the plane of the cover panel portions and also below the plane of the uppermost part of the adjacent side wall portions, the ends of said transverse wall portions merging into the side wall portions at each side of said intermediate bridge parts, the lower margins of said transverse wall portions being connected by structure at least a portion of which intermediate the cover side wall portions is disposed in a plane to engage the upper end of at least one of said upstanding posts in the bottom section when the cover is in closed position.

2. The carton set forth in claim 1 in which said pair of spaced downwardly extending transverse wall portions are of greatest depth intermediate the side wall portions and are of progressively less depth outwardly in the direction of the side wall portions, and being of least depth where they merge with the side wall portions.

3. The carton set forth in claim 1 in which the said pair of spaced downwardly extending transverse wall portions are of such varying depth that the structure connecting the lower margins thereof in transverse vertical section define a centrally located bearing portion and portions at each side thereof extending upwardly and outwardly, finally merging into the bridge parts of the respective side wall portions.

4. The carton set forth in claim 1 in which the said pair of spaced downwardly extending transverse wall portions are of such varying depth that the structure connecting the lower margins thereof includes a centrally located intermediate planar portion, portions at each side thereof extending abruptly upwardly and outwardly, merging with other portions extending upwardly and outwardly at a lesser angle to said central planar portion, finally merging into the bridge parts of the respective side wall portions.

5. The carton set forth in claim 1 in which the opposite ends of said pair of transversely extending wall portions are of arcuate construction as viewed in plan.

6. The carton set forth in claim 1 in which the portion connecting the lower margins of the said pair of transversely disposed wall portion is of planar form, the intermediate portions of said transverse wall portions including planar portions which converge downwardly from the plane of the cover panel portions to merge with margins of said first-mentioned planar portion.

7. The carton structure set forth in claim 1 in which each cover side wall portion is of planar formation and in which the bridge part thereof is coplanar therewith.

8. A molded pulp egg carton comprising a cover section and a bottom section integrally connected by a hinge along one side margin thereof, said bottom section being defined by an upwardly extending wall structure comprising side wall and end wall portions and provided with a plurality of contiguous egg-receiving cells arranged in two rows, said cell-forming structure including an intermediate row of hollow upstanding posts extending between opposite end wall portions and co-opcrating with the side and end wall portions to define said cells, said end Wall portions comprising a pair of arcuate segments curving from the respective side wall portions toward the center and terminating in an outwardly extending central flange portion, said cover section comprising a plurality of panel portions defined by downwardly extending side and end walls and a pair of spaced downwardly extending transverse wall portions intermediate the end wall portions, said cover side wall portions each including a bridge part intermediate its ends, extending upwardly from the lower margins of the side wall portion and terminating in a plane subtantially below the plane of the cover panel portions and also below the plane of the uppermost part of the adjacent side wall portions, the ends of said transverse wall portions merging into the side walls at each side of said intermediate bridge parts, the lower margins of said transverse wall portions being connected by structure at least a portion of which intermediate the cover side wall portions is disposed in a plane to engage the upper end of at least one of said upstanding posts in the bottom section when the cover is in closed position, the end wall portions of the cover comprising curved parts which follow substantially the curvature of the end wall parts of the bottom section when the cover is in closed position and which terminate in an outwardly extending central flange portion overlying the central flange portion of the bottom section.

9. The carton set forth in claim 8 in which the central flanges of said cover and bottom sections are relatively otfset to provide supporting abutment portions when the cover is in closed position.

10. The carton set forth in claim 8 in which one of aavsnsa flap integrally connected by a hinge along the other side margin thereof, said bottom section being defined by an upwardly extending wall structure comprising side Wall and end wall portions and provided with a plurality of contiguous egg-receiving cells successively arranged in row formation, said cell-forming structure including at least one row of hollow upstanding posts extending between opposite end wall portions, said cover section comprising a plurality of panel portions defined by downwardly extending side and end wall portions and a pair of spaced downwardly extending transverse wall portions intermediate the end wall portions, said cover side wall v portions each including a bridge part intermediate its said central flanges includes an offset portion adapted to contact with the confronting flange portion of the other section when the cover is in closed position.

11. The carton structure set forth in claim 8 in which each of said pairs of spaced downwardly extending transverse Wall portions comprises a pair of arcuate segments curving from the respective side wall portions toward the center and merging adjacent the center into a central wall portion spaced closer to the end wall of the panel, which it partly defines, than the major portion of said arcuate segments.

12. A molded pulp egg carton comprising a cover section and a bottom section integrally connected by a hinge along one side margin thereof and a one-piece locking end, extending upwardly from the lower margins and terminating in a plane substantially below the plane of the cover panel portions, the ends of said transverse wall portions merging into the side wall portions at each side of said intermediate bridge parts, the lower margins of said transverse walls being connected by structure at least a portion of which intermediate the cover side wall portions is disposed in a plane to engage the upper end of at least one of said upstanding posts in the bottom section when the cover is in closed position, said locking flap being disposed on the inner side of an adjacent cover side wall when the cover is in closed position and comprising an intermediate part extending across the bridge part of the cover section and adjoining end parts confronting the inner side of other parts of said cover wall portion, the latter being of greater height than the intermediate part and the entire top marginal portion of said flap terminating at a level substantially below the overlying portions of cover, thereby permitting the free seating of the lower marginal portion of one side wall portion of the cover section upon an upwardly facing part of the flap hinge when the cover is in closed position and also permitting engagement of at least one of the upstanding posts in the bottom section with an overlying depending portion of the cover intermediate the bridge portions of the cover side walls.

13. The carton set forth in claim 12, including structure in which the side wall portion of the cover section on the inner side of which the said flap is disposed when the cover is in closed position including a plurality of apertures, and said fiap including a plurality of projections formed and adapted to enter said apertures when the cover is folded to closed position, thereby serving to hold the sections against accidental swinging movement.

References Cited in the file of this patent UNITED STATES PATENTS 2,100,516 Read Nov. 30, 1937 2,160,893 Newsom June 6, 1939 2,529,140 Cox Nov. 7, 1950 2,560,847 Chaplin July 17, 1951 2,771,233 Cox Nov. 20, 1956 FOREIGN PATENTS 164,896 Australia July 2, 1953 '771,552 Great Britain Apr. 3, 1957