US3712532A

US3712532A - Egg carton

Info

Publication number: US3712532A
Application number: US00095427A
Authority: US
Inventors: J Alroy
Original assignee: Borden Inc
Current assignee: Hexion Inc
Priority date: 1970-12-07
Filing date: 1970-12-07
Publication date: 1973-01-23
Anticipated expiration: 1990-01-23

Abstract

An egg carton having a latching arrangement which includes inwardly projecting lugs on a front panel of the carton top cover which extend into corresponding holes on a latching flap attached to the carton tray. Reinforcing ribs extend across the carton top joining its front and rear panels to prevent spreading of the front panel. Depressions also are formed in the front panel of the carton top into which corresponding stacking lugs of another panel can fit. Two types of cartons are provided with differently located lugs, holes on the latching flap and reinforcing ribs so that the cartons can be stacked to occupy a smaller volume.

Description

Waited ewes Alroy 154] EGG CARTON [75] Inventor: John D. Alroy, Union City, NJ. [73] Assignee: Borden Inc., New York, NY.

[22] Filed: Dec. 7, 1970 21 Appl. No; 95,427

[451 Jan. 23, 1973 Primary Examiner-Donald F. Norton AttorneyGeorge P. Maskas, Edward L. Mandel] and George A. Kap

[57] ABSTRACT An egg carton having a latching arrangement which includes inwardly projecting lugs on a front panel of the carton top cover which extend into corresponding holes on a latching flap attached to the carton tray. Reinforcing ribs extend across the carton top joining its front and rear panels to prevent spreading of the front panel. Depressions also are formed in the front panel of the carton top into which corresponding stacking lugs of another panel can fit. Two types of cartons are provided with differently located lugs, holes on the latching flap and reinforcing ribs so that the cartons can be stacked to occupy a smaller volume.

11 Claims, 6 Drawing Figures Pmmgnmea ms 3,712,532

sum 1 or 2 W mvwron. JOHN D. ALROY ATTORNEYS PAIENTEnmzs ms SHEEI 2 [IF 2 INVENTOR. JOHN D. ALROY 21 eMuL ATTORNEYS EGG CARTON This invention relates to egg carton constructions and more particularly to a novel egg carton which has an improved latching and sealing arrangement as compared with prior art egg cartons and which also can be stacked prior to filling in open condition occupying considerably less volume than would be occupied by prior art egg cartons.

Egg cartons of the molded pulp or foamed plastic material are well-known in the art. Typical of such egg cartons are those disclosed in Reifers U.S. Pat. No. 2,888,183. These cartons include a tray having a number of cells for holding a like number of eggs, a non-cellular cover hinged to the backside of the tray so that it may be swung to a closed position overlying the tray, and a latching flap attached to the front panel of the tray portion. A latching arrangement is formed by cooperating members on the latching flap and the front wall of the cover member which include one or more projections on the latching flap and corresponding openings in the cover front panel.

In a carton such as the type disclosed in the aforesaid Reifers U.S. Pat. No. 2,888,183 there is a substantial unsupported central area of the top wall of the noncellular cover member which has a tendency to warp during manufacturing. This unsupported central area also proved to be unsatisfactory when a number of loaded cartons were stacked one on top of another since when it is subjected to a load condition, the cover bows. This causes disengagement of the latching members on the cover front panel and the latching flap.

An effort to correct the aforesaid deficiencies is shown in U.S. Pat. No. 3,184,133 to J. W. Boyd et al. In that patent, a hollow partitioning rib is formed on the top surface of the cover which depends from and divides the top surface into two sections. The rib rigidly interconnects the front and back walls, or panels, of the cover to prevent some of the aforesaid disadvantageous effects from occurring. In addition, several transverse gussets are provided to connect the walls of the rib to prevent any tendency of the cover to bend or flex along the rib s longitudinal axis. The same type of latching arrangement used in the Reifers patent is also used by Boyd.

' The carton of the Boyd patent also suffers from several disadvantages. First of all, the latching arrangement utilizes members which protrude from the latching flap through holes in the cover front panel. Therefore, a possibility exists that the latching flap can be disengaged accidentally by pushing in on the protruding members extending through the front panel.

Further, the construction of this carton is such that it flap attached to the front thereof. A cover is hinged to the rear edge of the cellular tray. A plurality of reinforcing ribs extend across the top wall of the cover connecting the front and rear panels. In accordance with one aspect of the invention, the ribs are in the shape of a modified box beam which are simple to form and provide substantial rigidity. Further, the latching flap is formed with a number of holes and a corresponding number of inwardly extending lugs or posts are formed on the inner face of the cover front panel. To securely close the carton it is only necessary to move the cover down over the latching flap until the lugs on the cover extend into the holes on the latching flap. The latching flap has a natural tendency to move outwardly, toward the cover front panel. The reinforcing ribs aid in providing a firm latch since the cover front panel is prevented from spreading outwardly. Thus, a secure engagement is produced between the posts on the cover front panel and the apertures in the latching flap.

In addition to the aforesaid latching arrangement, the subject invention also incorporates a unique stacking feature which decreases the stacking density of the cartons, which would otherwise be relatively large due to the presence of the latching lugs. In accordance with the invention, two different types of cartons are provided to facilitate stacking when empty with the covers open. Both types of cartons utilize the latching arrangement previously described. However, as between the two carton types, each has a different number of lugs and holes and the location of these elements are different. For example, in a first type of carton there are two lugs and two holes while in the second type of carton there are three lugs and three holes. In the first carton type, having two lugs and two holes, the cover front panel is formed with three stacking depressions at positions corresponding to the three lugs on the cover of the second carton type so that the three lugs of the second type of carton can fit within the depressions. In a similar manner, the cover front panel of the second carton type is formed with two depressions into which the two lugs of the first carton type can be located. Thus, the cartons can be stacked with a relatively low density.

It is therefore an object of the present invention to provide a novel egg carton with a latching arrangement wherein inwardly extending lugs on the front panel, of the top cover protrude into holes of a latching flap.

Another object is to provide an egg carton which can be stacked, in which the latching lugs of one type of carton fit within mating depressions in a second type of carton.

A further object is to provide an egg carton utilizing a latching arrangement with inwardly extending lugs on the front panel of a cover projecting into holes in a latching flap, the cover also being provided with a strengthening rib extending between the front and rear panels to prevent the front panel from spreading.

An additional object is to provide an egg carton with reinforcing ribs in the cover having the shape of modified box beams connecting the front and rear panels of the cover to strengthen the cover top panel.

Other objects and advantages of the present invention will become more apparent upon reference to the following specification and annexed drawings, in which:

FIG. 1 is an isometric view of a first type of egg carton made in accordance with the subject invention in an open condition;

FIG. 2 is a view similar to FIG. 1, of a second type of egg carton;

FIG. 3 is a perspective view showing the egg carton of FIG. 2 closed;

FIG. 4 is a first end view in section along the plane shown by lines 4-4 of FIGS. 1 and 2 showing the stacking of the cartons;

FIG. 5 is a second, fragmentary, end view in section showing the stacking of the cartons along the cross-sectional plane of lines 5-5 of FIGS. 1 and 2; and

FIG. 6 is a front perspective fragmentary view of a portion of another form of latching flap.

Two types of egg cartons, respectively designated I and II, are shown in FIGS. 1 and 2. Except for the placement of the reinforcing ribs, latching lugs and corresponding holes on the latching flap, the construction of the two egg carton types are identical. Therefore, they are both described simultaneously with the suffix reference numeral -1 given to the differently located elements of carton type I and suffix reference numeral 2 given to the elements of carton type II. Each of the carton types is formed of the same material and by the same process. For example, they can be made of pulp, cardboard or plastic by any suitable process, such as molding.

Each carton has a lower tray 10 formed with a number of individual, generally concave cells 12, there being one cell 12 for each egg. The bottom of each cell is shown as being flat. In the most common configuration, which is shown in the drawings, there are two rows of six cells 12 to hold a dozen eggs. Of course, other cell arrays, such as three by four, can be used. A quad of adjacent cells are joined by a generally convex projection 13 which are the terminal points of cell divider walls 14. The projections 13 are hollow on the bottom side of the tray so that another projection 13 can fit within the hollow portion when the cartons are stacked. Walls 14 extend both parallel and transversely to the longitudinal axis of the tray 10. The projections 13 extend above the cell walls and also above a peripheral rim 16 which is formed around all four sides of the tray. Extending upwardly from the front of the peripheral rim 16 is a latching flap 20. The latching flap 20 is bent upwardly from rim 16 so that it has a natural tendency to move outwardly with respect to the central cell area of tray 10.

A cover 30 is hinged at 32 to the rear portion of the tray rim 16. The hinge can be of any suitable, conventional construction. The cover 30 has respective front, rear and

side panels

30a, 30b and 300 which surround and depend downwardly from a top wall 30d. The

panels

30a, 30b and 300 taper outwardly slightly from top panel 30d so that the covers of the carton also can be stacked. A partial peripheral lip 33 is formed around the front and the two side panels 300 and 30c.

A plurality of reinforcing ribs 35 are formed in the top wall 30d and extend between the cover front and

back panels

30a and 30b. The ribs 35 depend downwardly from the top panel 30d and are shown as being of generally rectangular shape with two parallel side walls and a joining bottom wall. This forms a threesided box-beam. As seen in FIG. 3, the ribs 35 are depressed areas of the cover top panel 30d which are formed during the molding operation. It has been found that the box-beam construction provides substantial rigidity between the front and

rear panels

30a and 30b. It is preferred that the ribs 35 each have a depth of from about one-quarter to about one-third the total height of the cover to provide the desired structural rigidity between the front and rear panels.

A plurality of inwardly projecting latching lugs 40 are formed on the front panel 30a. It is preferred that at least two such lugs 40 be provided to assure adequate latching. Two lugs 40-1 are shown for carton type I of FIG. 1, while carton type II of FIG. 2 has three lugs 40-2. It is preferred that the lugs 40 be angled upwardly slightly, with the inner end of each lug being pointed toward the cover top 30d. This provides a better latching action as is described below.

A plurality of lug-stacking depressions 45 are also formed on the front panel 30a of each carton. The size and shape of each lug-stacking depression 45 is such that a lug 40 can fit therein. The bottom of each lug 40 is closer to the tray peripheral edge 33 than the bottom of a depression. This permits stacking, as is described below. The depressions are shown as being generally rectangular in shape and having their walls extending inwardly toward the interior of the cover. Any suitable shape can be used.

As shown in FIGS. 1 and 2, each stacking lug depression 45 has its center on a plane which passes through the longitudinal axis of a rib 35 and lies parallel to the side walls forming the rib. If desired, the portion of the rib 35 which terminates at the front panel 30a can be extended downwardly toward the cover peripheral edge 33 so that the termination of a rib 35 at the front panel 30a will join with the walls defining the corresponding depression 45. Alternatively, the rib can be made deeper to obtain the latter structure.

Carton type I has three lug stacking depressions 45-1 on the front panel 30a located at points corresponding to the three latching lugs 40-2 on a carton type II. In a similar manner, carton type II has two stacking-lug depressions 45-2 on its front panel 30a, located at points corresponding to the two latching lugs 40-1 of a type I carton.

The latching flap 20 has a height above the tray rim 16 which is preferably slightly less than that of the cover front panel 30a. A plurality of circular openings 50 are formed in the latching flap at positions which are in line with the latching lugs 40 on the same cartons front panel 30a. Each opening 50 has a diameter sufficiently large to accept a lug 40. The latching flap is also formed with a number of cutouts 52 of a shape corresponding generally to the shape of the termination of the cartons reinforcing ribs 45 at the front panel 30. Each cutout 52 is in line with a respective rib 45.

The latching flap 20 is preferably formed in a generally serpentine shape, viewed from the top, with outwardly extending portions 20a and inwardly extending portions 20b. The apertures 50 and the cutouts 52 are formed in the inwardly extending portions 20b of the flap. The inwardly extending portions 20b are in line with the projections on the front panel formed by the projections 45 so that these projections will not be able to push the latching flap inwardly too far, if at all. It should be understood, of course, that a straight flap 20 can be employed instead of the serpentine shape shown.

As is seen by comparing FIGS. 1 and 2, the latching flaps of carton types I and II differ somewhat. A type I carton has cutouts 52-1 on the two end and center outwardly extending flap portions 20b and openings 50-1 on the two intermediate portions b. This pattern of openings and cutouts is reversed on the flap of a type II carton.

To seal the carton after it has been filled with eggs, the latching flap 20 is bent up to the position shown, if it is not already in that position. The cover is plowed down until the latching lugs lock into the corresponding openings 50 in the latching flap. The latching flap has an inherent tendency to move outwardly. However, this is resisted by the flap engaging cover front panel 300. The reinforcing ribs prevent an outward spreading of the front panel 30a so that the latch is kept secure. Due to the upward angle of lugs 40, a wedging action is produced between a lug and 15 the portion of the flap surrounding the corresponding opening 50, when there is an upward force on an already sealed cover. To open the cover both an upward and an outward force must be applied to cover front panel 30a.

It should be noted that the locking lugs 40 extend inwardly from panel 300 and are not exposed as in the carton of the aforesaid Reifers patent. Therefore, there is little or no likelihood of the cover being accidentally disengaged from the apertures 50 by someone pushing inwardly on the latching lugs, as could occur in the Reifers structure.

FIGS. 4 and 5 show the stacking of the types I and II cartons which are designated accordingly. A type II carton of FIG. 2 is the lowest carton in the stack, with a type Icarton of FIG. 1 nested on top of it, and a second type II carton nested on top of the type I carton. Crosssections are shown at two different positions of the two carton types in the stack. While only three cartons are shown, since this demonstrates the principles of the invention, it should be understood that a greater number of cartons can be stacked one within the other. Since the trays 10 of both types of cartons are identical, they stack with the projections 13 nesting inside of each other. The latching flap 20 of each carton fits within the flap of the next lower carton of the stack.

The bottom carton in the stack is a type II carton and the sections taken along lines 4-4 of FIGS. 1 and 2,

shows a stacking lug40-2 of this carton nesting within a depression -1 of the middle type I carton. Similarly, in FIG. 5, the latching lug 40-1 of the middle type I carton is shown nested in the stacking depression 45-2 of the top type II carton. As should be apparent, the three latching lugs 40-2 of the lowest type II carton fit within the three depressions 45-1 of the middle type I carton while the two lugs 40-1 of the middle type I carton fit within the two depressions 45-2 of the top type II carton. This nesting sequence of parts 40 and 45 is repeated for additional cartons added to the stack.

The use of the two different carton types and their respectively differently located latching lugs and lug depressions, which are complementary to each other, increases the stacking density of the cartons. It would take a considerably greater volume to stack the same number of cartons if the stacking arrangement of the subject invention was not utilized. This should be apparent when it is considered that the cover of each carton would be able to nest into the cover of the next lower carton only to a point where the front panel of the cover of the upper carton would be stopped by the inwardly projecting latching lugs on the cover of the next lower carton. By utilizing the subject invention the cover of the upper carton can move down further into the next lower carton on the stack since the latching lugs of the latter now fit into the depressions of the former thereby permitting further downward movement of the upper carton than could previously be obtained.

As shown in FIGS. l and 2, each rib 35 and its corresponding flap cutout 52 lies in line with the center of a respective projection 13 in both carton types. This particular location for these elements are not critical. They are desirable, however, from the point of view that the height of a projection 13 and/or the height of a rib 35 in line with it can be made so that they engage one another when the cover is closed. This increases the load bearing capacity of the cover since it is supported at the additional points of its top panel 30d where the ribs 35 engage the projections 13.

FIG. 6 shows a portion of a modified form of latching flap. Here, the

step portions

20a and 20b of the flap are reversed so that portions 20b lie closer to the front panel of the cover when it is closed. This provides better latching action since portions 20b will lie closer to the cover front panel when it is closed. Each cutout 72 on a flap portion 20b which lies in line with a rib 35 and a depression 45 is formed with two

parts

72a and 72b. The upper part 72a starts at the upper edge of the flap and is shaped to accept a portion of a corresponding reinforcing rib 35 as in FIGS. 1-5. The lower part 72b is shaped to accept an inward projection on the front panel 30a of a carton top which forms the depression 45. Thus, the outwardly extending portions'20b of the flap will all lie close to the cover front panel when it is closed since the projections of depressions 45 will fit into cutout part 72b and cannot push the flap 20 inwardly. While the two parts of the cutout are shown joined together, it should be understood that they can be separated.

What is claimed is:

1. In a carton comprising a cellular tray, a latching flap attached to and extending upwardly from the front of the tray, said latching flap formed with a plurality of openings, a cover hingedly attached to the rear of said tray, said cover having a front, rear and side panels which depend from the cover top, a plurality of inwardly projecting latching lugs of a number equal to the number of openings on the latching flap formed on the front panel of said cover at locations corresponding to said openings, said latching lugs extending into said openings when the cover is moved over the latching flap to engage the portions of the latching flap surrounding the openings to hold the cover to the flap;

the improvement wherein said front panel is also formed with at least one inwardly extending projection which defines a depression on the outside of the front panel projection at a position to accept an inwardly extending latching lug on the cover of the front panel of another carton stacked in an open condition below the carton whose front panel has said depression.

2. The improvement of claim 1 wherein a plurality of reinforcing ribs are formed in the top panel of said cover joining the front and rear. panels thereof.

3. The improvement of claim 2 wherein said latching flap is also formed with at least one cutout at the upper edge of the panel into which a portion of the rib fits when the cover is closed over said latching flap, and

another cutout into which said projection forming the depression fits when the cover is closed over said latching flap.

4. The improvement of claim 3 wherein one of said ribs and a said projection forming a depression lie along the same line, said cutouts being formed as one continuous cutout having one portion to accept the said portion of the rib and another portion to accept said projection when the cover is closed over said latching flap.

5. In a carton comprising a cellular tray, a latching flap attached to and extending upwardly from the front of the tray, said latching flap formed with a plurality of openings, a cover hingedly attached to the rear of said tray, said cover having a front, rear and side panels which depend from the cover top, a plurality of inwardly projecting latching lugs of a number equal to the number of openings on the latching flap formed on the front panel of said cover at locations corresponding to said openings, said latching lugs extending into said openings when the cover is moved over the latching flap to engage the portions of the latching flap surrounding the openings to hold the cover to the flap;

the improvement wherein said front panel is also formed with a plurality of extending inwardly projections each of which defines a depression on the outside of the front panel, each of said depressions being located at a position to accept an inwardly extending latching lug on the cover of the front panel of another carton stacked in an open condition beneath the carton whose front panel has said depressions.

6. The improvement of claim 5 wherein said projections forming said depressions on the front panel of the cover are offset from the inwardly extending latching lugs on said front panel.

7. The improvement of claim 6 wherein there are a different number of projections and latching lugs on the front panel of the cover.

8. The improvement of claim 5 and further comprising in combination therewith a second carton having the same tray construction as the first-named carton so that the trays of said two cartons can nest one within the other, said second carton also having a latching flap extending upwardly from the front of the tray, a cover hingedly attached to the rear of the tray, said cover having a front, rear and side panels which depend from the cover top, a plurality of inwardly extending latching lugs formed on the front panel of said cover equal in number to the depressions on the front panel of said first-named carton and located to fit therein when said second carton is stacked below said first carton, and a plurality of inwardly extending projections on the front panel of said second carton each of which forms a depression, said projections located on the front panel of said second carton so that the latching lugs on the front panel of the first-named carton can fit therein when the said first-named carton is stacked below said second carton.

9. The improvement of claim 8 wherein said firstnamed carton has an odd number of latching lugs and an even number of projections forming said depresionsand said second carton has an even number of atching lugs and an odd number of pro ections forming the depressions.

10. The improvement of claim 9 wherein each said carton has a respective reinforcing rib extending between the front and rear panels of the cover and lying in line with each said projection forming a depression.

11. The improvement of claim 10 wherein each said latching flap is formed with a cutout within which a portion of a reinforcing rib fits when the cover is closed.

Claims

1. In a carton comprising a cellular tray, a latching flap attached to and extending upwardly from the front of the tray, said latching flap formed with a plurality of openings, a cover hingedly attached to the rear of said tray, said cover having a front, rear and side panels which depend from the cover top, a plurality of inwardly projecting latching lugs of a number equal to the number of openings on the latching flap formed on the front panel of said cover at locations corresponding to said openings, said latching lugs extending into said openings when the cover is moved over the latching flap to engage the portions of the latching flap surrounding the openings to hold the cover to the flap; the improvement wherein said front panel is also formed with at least one inwardly extending projection which defines a depression on the outside of the front panel projection at a position to accept an inwardly extending latching lug on the cover of the front panel of another carton stacked in an open condition below the carton whose front panel has said depression.

2. The improvement of claim 1 wherein a plurality of reinforcing ribs are formed in the top panel of said cover joining the front and rear panels thereof.

3. The improvement of claim 2 wherein said latching flap is also formed with at least one cutout at the upper edge of the panel into which a portion of the rib fits when the cover is closed over said latching flap, and another cutout into which said projection forming the depression fits when the cover is closed over said latching flap.

5. In a carton comprising a cellular tray, a latching flap attached to and extending upwardly from the front of the tray, said latching flap formed with a plurality of openings, a cover hingedly attached to the rear of said tray, said cover having a front, rear and side panels which depend from the cover top, a plurality of inwardly projecting latching lugs of a number equal to the number of openings on the latching flap formed on the front panel of said cover at locations corresponding to said openings, said latching lugs extending into said openings when the cover is moved over the latching flap to engage the portions of the latching flap surrounding the openings to hold the cover to the flap; the improvement wherein said front panel is also formed with a plurality of extending inwardly projections each of which defines a depression on the outside of the front panel, each of said depressions being located at a position to accept an inwardly extending latching lug on the cover of the front panel of another carton stacked in an open condition beneath the carton whose front panel has said depressions.

9. The improvement of claim 8 wherein said first-named carton has an odd number of latching lugs and an even number of projections forming said depressions and said second carton has an even number of latching lugs and an odd number of projections forming the depressions.