Egg carton

[57] ABSTRACT

A one-piece egg carton formed from molded material comprising a hollow tray member having a plurality of egg receiving pockets; a hollow cover member having a front wall; a lock flap hinged to and upstanding from the front edge of the tray member and adapted to be contained within the cover member behind the front wall thereof when the carton is in closed condition with the front surface of the lock flap disposed against the rear surface of the cover member front wall; the cover member front wall having a rearwardly extending abutment received within a forwardly facing pocket presented by the lock flap to maintain the carton in closed condition. The lock flap has a longitudinally extending latching bar integral therewith adapted to be received within a longitudinally latching opening situate along intermediate portions of the rearwardly extending abutment in the cover.

Claim, 8 Drawing Figures

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PATENTED: 9 is/2

3,661,320

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ATTORNEYS

3,661,320

EGG CARTON

This application is a continuation-in-part of application Ser. No. 705,194, filed Feb. 13,1968 now abandoned.

This invention relates to egg cartons and more particularly to a one-piece egg carton formed from molded material such 5 as foamed polystyrene.

It is an object of the invention to provide an improved locking arrangement between the tray and the cover portions of the carton.

A further object is to provide an arrangement wherein the 10 tray of the carton has a lock flap hinged thereto and adapted to cooperate with the front wall of the tray cover to provide interlocking engagement between the tray and cover.

A more specific object is the provision of a locking arrangement between a tray lock flap and cover front wall wherein the 15 cover front wall has a rearwardly extending projection which is received within a forwardly facing pocket of the lock flap to maintain the carton in closed condition.

A yet further object is to provide a bar in the front lock flap adapted to cooperate with a latching opening in the rear- ²⁰wardly facing abutment in the cover.

FIG. 1 is a perspective view of an egg carton embodying features of the invention;

FIG. 2 is a front elevation of the structure shown in FIG. 1, with portions of the carton cover broken away; transverse ver- ²³tical sections taken on lines 3—3 and 4—4, respectively of FIG. 2;

FIG. 5 is a fragmentary plan view of a portion of the carton as seen in an open condition with the lock flap and cover shown folded away from tray so as to lie in a generally ^{26 * * * 30 * * * *}horizontal plane with the tray;

FIG. 6 is an enlarged section of a portion of the structure shown in FIG. 4 taken also approximately along the line 6—6 of FIG. 1 looking in the direction of the arrows;

FIG. 7 is a fragmentary sectional view illustrating the nest- ³⁵ing of related portions of similar egg cartons; and

FIG. 8 is a view similar to FIG. 6 showing details of a latching opening in the cover and a latching bar in the lock ^flaP· ₄₀

Referring to FIGS. 1 and 5, the improved carton, which is preferably formed of molded plastic material such as polystyrene, includes a tray member indicated generally at 10, having an integral cover member indicated generally at 40, and a lock flap indicated generally at 70, which is hinged to ₄₅the tray member and adapted for interlocking engagement with the cover member 40.

As seen in FIGS. 3 and 5, tray member 10, includes a plurality of contoured pockets or cells, indicated generally at 12, adapted to receive eggs. Each of the cells includes a generally 5Q vertically extending, contoured side wall 14, and a preferably flat bottom wall 16. In order to afford additional cushioning for the bottom of the cells there may be provided a plurality of integral ribs 18, at the junctures of the side and bottom walls of the pockets.

Between each set of four pockets there is formed an integral vertically extending corner post 20. Adjacent cells and corner posts are interconnected by a plurality of longitudinally extending partitions 22, and transversely extending partitions 24. At its upper edge, tray member 10 includes an integral 60 generally rectangular horizontally disposed upper shelf or rim

26, having generally similar front and rear side portions 28, and end portions 30. As best seen in FIGS. 1 and 5, end portions 30 each have a central offset or recess 32 which provides an end opening 34 between the tray and cover members of the 65 carton to ventilate the same.

As seen in FIGS. 1 and 2, cover member 40 includes a preferably flat generally rectangular top wall 42, having opposed front and rear side walls 44 and 46, and end walls 48 formed integrally with the edges thereof and depending 70 therefrom to form a box-like enclosure. The side and end walls are merged together at the corners of the carton.

As seen in FIGS. 1, 4 and 6, the cover front side wall 44 is provided with a plurality of recessed areas 50, each of which includes an upper portion 52 and lower portion 54 spaced 75 from each other to provide a latching opening 56 therebetween. Upper portion 52 has its lower edge presenting a preferably flat downwardly facing surface 58 which is coextensive with latching opening 56 while the lower portion 54 has its upper edge provided with flat upwardly facing surface 60 also coextensive with latching opening 56. Lower portion 54, as best seen in FIG. 6, is rounded and curves upwardly and inwardly to present an inner camming surface 62, and the purpose of these surfaces together with the latching opening 56 will be described later in the specification.

As seen in FIGS. 3,4, and 5, tray and cover members 10 and 40 are hingedly attached at their rear edges by means of a relatively narrow rigid longitudinally extending hinge bar 64 which is hinged at its lower edge along hinge line 66 to tray member 10 rim rear side portion 28, and which is hinged at its upper edge along hinge line 68 to cover member 40.

As seen in FIGS. 5 and 6, lock flap 70 includes a relatively narrow flat elongated panel 72 hingedly attached along hinge line 73 to the upper forward edge of tray member rim front portion 28. Panel 70 is provided with a plurality of pockets 74 with forwardly facing openings 77 which are formed in the material from the front side thereof to provide rearwardly projecting bosses 75 on the inside or rear surface of lock flap 70. Flap 70 has a rear upwardly extending surface 76, and a rear downwardly facing surface 78, the purpose of which is hereinafter described.

As best seen in FIGS. 6, the novel configuration of the lock flap 70 and that of the cover member front side wall 44, provides not only a means for effecting an interlocking connection between the tray and cover member, but also transfers stress from cover member to the tray member to provide greater strength and rigidity for the carton, this being of importance when the carton is stacked in a pile with similar filled cartons.

As best seen in FIG. 6, when the carton is closed by bringing the cover member over the locking flap, the camming surfaces 62, on the cover member front side wall, ride over the upper edge 76, of lock flap panel 72, in a cam-like action to facilitate closure of the carton. After the lower portion 54 rides over the latch bar 80 on lock flap panel 72 immediately above pocket 74, lower portion 54 is then received within pocket 74 to prevent the accidental opening of the carton. If the cover were to be pulled up, without deflecting the carton slightly, the upwardly facing surface 60 on lower portion 54 would abut downwardly facing surface 82 on lip 80 to prevent further movement of the coyer member.

In addition to the locking action described the latch bar 80 moves into the latch opening 56, further facilitating the locking action. This is best seen with reference to FIG. 8.

Also, as best seen in FIG. 6, when the cartons are stacked, the weight on the cover member is transmitted from the downwardly facing surface 58, on the upper portion, to the upwardly facing surface 76, on lock flap panel 72, and the vertical force is thereafter transmitted from the downwardly facing surface 78 of lock flap boss 75 to the upper surface of tray member rim 26.

In a similar manner, at the rear of the carton, the cover member rear side wall 46 rests on the rear hinge bar 64 which in turn rests directly on the upper surface of tray member rim

Thus it will be seen, that there is provided a carton having positive locking means between the cover and the tray, a high degree of stacking strength because of the relationship of the cover member to the tray member, and structural arrangement which will permit efficient nesting of plurality of cartons when they are in the open position, as shown in FIG. 5.