US3120901A

US3120901A - Molded egg tray

Info

Publication number: US3120901A
Application number: US246506A
Authority: US
Inventors: Boyd James William
Original assignee: Packaging Corp of America
Current assignee: Packaging Corp of America
Priority date: 1962-12-21
Filing date: 1962-12-21
Publication date: 1964-02-11
Anticipated expiration: 1981-02-11
Also published as: GB1038230A

Description

Feb. 11, 1964 J. w. BOYD 3,120,901

MOLDED EGG TRAY Filed Dec. 21, 1962 3 Sheets-Sheet l 0 a' i i i r "2 Feb. 11, 1964 J. w. BOYD MOLDED EGG TRAY 3 Sheets-Sheet 2 Filed Dec. 21 1962 Feb. 11, 1964 J. w. BOYD MOLDED EGG TRAY 3 Sheets-Sheet 3 Filed Dec. 21, 1962 ly/ms???" I Qwp/Miagaga mawagm' United States Patent C) 3,120,901 MOLDED EGG TRAY James William Boyd, Griffith, Ind, assignor to Packaging Corporation of America, Evanston, 111., a corporation of Delaware Filed Dec. 21, 1962, Ser. No. 2 46,5636 7 Claims. ((11. 217-465) This invention relates to a molded egg tray and more particularly to an egg packaging filler flat having means thereon for facilitating the denesting of the filler flats from a stacked relationship.

In order to package eggs into standard egg cases, filler flats are employed. These filler flats are formed of an absorbent cushioning material such as molded pulp and have alternate rows of pockets and posts which combine to maintain each egg in protective isolated relationship with respect to the adjacent eggs in the case. As the filler flats are manufactured, they are stacked in nested relationship in order to provide for compact storage and shipment, and it is customary to actually compress these filler flats in their nested condition so that the most compact unit may be achieved. However, when the nested filler flats are received by the egg packaging plant, they must be separated or denested so that they may be placed individual-1y into the egg case as the eggs are packed. Since the tightly nested portions of the filler fiats tend to frictionally engage and resist separation, some means must be provided for preventing or overcoming this frictional jamming. Heretofore, it has been proposed that this tendency toward jamming be minimized by maintaining sufficient spacing between overlying filler fiats to reduce excessive frictional engagement of the nested portions thereof. United States Patent No. 2,997,196 dated August 22, 1961, suggests that the desired spacing may be maintained by means of lugs molded on the sides of the posts in the area between the pockets, i.e., on the ribs which connect the posts together. United States Patent No. 1,919,028 dated July 18, 1933, suggests that the top portions of the ribs of a molded pulp egg receptaole may be filled in or thickened, which of course not only will tend to maintain the desired spacing between nested structures but will also tend to increase the rigidity of the structures. While such devices do serve to main tain a minimum spacing between stacked filler flats, thus reducing excessive initial frictional engagement of the nested portions thereof, they have not been uniformly successful in eliminating the subsequent jamming tendencies of the stacked filler flats.

it is, therefore, one object of this invention to provide a filler fiat having improved means thereon for facilitating the separation therefrom of a second and similarly constructed filler flat which has been initially placed in overlying nested relationship with respect thereto.

It is another object of this invention to provide a filler fiat having means thereon which will not only maintain the desired spacing between that filler flat and a similarly constructed overlying filler flat, but which will facilitate the proper and unhindered removal of the overlying filler flat therefrom.

It is still a further object of this invention to provide a filler fiat having means thereon which will permit a similarly constructed filler flat to be withdrawn with unhindered ease from overlying nested relationship with respect thereto simply by raising one edge of the over lying filler flat.

Other objects will be seen, and a fuller understanding of the invention may be had by referring to the following description and claims taken in conjunction with the accompanying drawing.

The molded filler fiat constructed in accordance with 3,120,901 Patented Feb. 11, 1964 ice this invention comprises a sheet having a plurality of alternate rows of upwardly extending posts and downwardly extending pockets. Disposed outwardly of the terminal row of posts at each of two opposite sides of the filler fiat is a row of partial pockets, and a plurality of solid projections are provided, these projections extending upwardly from the plane of the sheet and at least portions of the projections being disposed outwardly adjacent the peripheral edge of the filler flat. It is preferred that these outwardly extending portions of the projections actually extend beyond the outermost extremities of the half pockets. Thus, the projections act as fulcrums to permit the nested filler flats to be pivoted apart quite easily, even if compressed, by merely lifting at one edge of each overlying filler fiat. The provision of these outwardly and upwardly extending solid projecions which extend as close to the very edge of the sheet as possible in order .to provide a fulcrum as high above the plane of the sheet and as far from the nested pockets and posts as is possible, is an important feature of this invention.

Means may be provided intermediate the terminal row of posts for maintaining the spacing of the nested portions of the filler flats in sufficiently spaced relationship to pre vent any possible jamming of these intermediate portions.

With reference to the drawings:

FIGURE 1 is a top plan view of onehalf of a filler flat embodying the invention, the other half of the filler flat being a duplicate thereof;

FIG. 2 is an enlarged fragmentary top plan view of the filler flat shown in FIG. 1;

FIG. 3 is an enlarged sectional elevation view of the filler fiat taken substantially along lines 33 of FIG. 1 and showing a plurality of filler flats in superposed nested relationship;

FIG. 4 is an enlarged sectional elevation view similar to FIG. 3 showing the manner in which the: previously nested filler flats may be denested or separated;

FIG. 5 is a sectional view taken along line -5-5 of FIG. 3 and showing the underside portion of one of the posts;

FIG. 6 is an enlarged sectional view taken substantially along line 66 of FIG. 2;

FIG. 7 is a fragmentary end elevation view taken in the direction indicated by the arrows 77 of FIG. 2;

FIG. 8 is a fragmentary top plan view on an enlarged scale of a filler fiat of slightly modified design;

FIG. 9 is a sectional elevation view of the modified filler fiat illustrated in FIG. 8 taken substantially along line 9-9 of that figure;

FIG. 10 is a fragmentary top plan view on an enlarged scale of still a further modification of the filler flat embodying the invention; and

FIG. 11 is a sectional elevation view of the filler fiat illustrated in FIG. 10 taken substantially along line 11-11 of that figure.

With more particular reference to the drawings, the filler flat v10 is generally of the type described in Patents No. 1,970,436 and No. 2,872,062. The filler flat consists of a continuous piece of sheet material preferably molded pulp having alternate rows of pockets 12 and posts 14. The pockets 12 are generally fnusto-oonical in shape extending downwardly from the plane of the sheet, and they are aligned in two transverse directions, generally parallel to the peripheral edges of the sheet. The posts 14, which are approximately as high as the pockets 12 are deep, are also of generally frustro-conical shape although somewhat narrower and steeper than the pockets, and these posts are also aligned in two transverse directions generally parallel to the peripheral edges of the sheet.

At each of two opposite sides of the filler fiat 10 is a terminal row 14a of posts 14, and disposed outwardly of and extending partially between the posts in the terminal rows 14a are half or partial pockets 16, which like pockets 12 extend downwardly from the general plane of the sheet. A pair of finger grip recesses 18 are provided in the half pocket area at the opposite sides of the sheet and these facilitate manipulation of the filler flat within the egg case. Extending transverse to the rows of partial pockets 16 along each of the two adjacent edges of the sheet is a row of half or partial posts 20 which are disposed outwardly of each of the two terminal rows 12a of full pockets 12. A of an inch radius is provided between the planar top and the conical sloping sides of each post 14 and each half post 20. Thus, sharp edges are avoided at the tops of the posts and half posts and the tendency toward jamming during subsequent removal of the filler flats from nested relationship.

With this construction, every other loaded filler flat in the egg case is rotated 90 degrees on its vertical axis relative to the underlying loaded filler flat, so that the bottoms of the pockets 12 of the overlying filler flat will rest upon and be supported by the tops of the post 14 of the underlying filler flat. The eggs, of course, rest in the pockets 12 of each underlying filler flat and extend upwardly partially into the hollow posts of the overlying filler flat. It will be noted that dividing portions 22 remain between the pockets 12 and lands 24 remain between the half posts 20 and half pockets 16; also, a continuous peripheral rim 26 is disposed outwardly of the half pockets and half posts. In the embodiments of the invention illustrated in FIGS. 1-7 and -11 the tops of the dividing portions 22 are all disposed in the plane of the sheet. In the embodiment of the invention illustrated in FIGS. 8 and 9, and as will be more fully described, the dividing portions are shown as being raised above the plane oi the sheet while the lands and peripheral 'rirn remain in the plane of the sheet. Insofar as this description is concerned, the plane of the sheet may be considered to be that plane defined by the lands 24 and the peripheral rim 26 or the highest of these.

The filler flats 10 are formed by the usual vacuum pulp process. That is, pulp floating in a slurry is drawn by vacuum against a screen form or mold which passes through the slurry, thus forming the entire sheet with the pockets 112, the posts 14 and all other portions in a single operation. The thus formed filler flats are then dried and they are stacked in nested relationship in order to provide a compact unit for storing and shipping. To assure this compactness, the stacked and nested filler flats are usually compressed mechanically in a direction normal to the planes of the sheets, and because of the relatively steep angles of the side portions of the pockets 12 and posts 14 and the consequent susceptibility of these portions to jam when nested, difficulty may be encountered by the egg packing plant in attempting to separate the filler flats unless some means is provided for properly facilitating the denesting of these stacked filler flats.

For this purpose a plurality of solid projections 23 are provided on each filler flat. These solid projections 28, which may be formed by crowding the fibers into a narrow fold of the screen form at that point, extend upwardly from the plane of the sheet, and at least portions of these projections are disposed outwardly of the terminal rows 14a of posts 14 a distance at least equal to half the distance between these posts and the peripheral edge of the filler fiat. Each projection 28 is preferably attached to a corresponding post in the terminal row, and in the illustrated embodiments of the invention these projections extend outwardly from these posts to at least approximately the outermostextremities of the half pockets 16, and preferably beyond. It is preferred that the height of the projections 23, that is, the elevation of these projections from the plane of the sheet of the filler flat, be on the order of one-fourth the height of the posts 14 above that plane. Since the height of the posts in the preferred embodiment is bet-ween about of an inch and 1 inch, the height of the projections 28 should be between about of an inch and to about A of an inch, although reasonably satisfa-ctory results can be obtained if the height of the projections is on the order of Me of an inch or better above the plane of the sheet. Actually, it is preferred that the projections extend upwardly as high as possible, but this is limited by the pulp forming process, for if the height of the projection is increased much over that of A1 of an inch a corresponding groove or channel tends to form on the opposite (under) side of the sheet.

The outward extension of each projection 28 is preferably as great as possible, although again this is limited by the manufacturing process and usually the end of the projection must be recessed from the edge of the sheet on the order of about of an inch to permit withdrawal of the wet filler flat from the vacuum mold in the manu- 'facturing process. For best efficiency the projections 28, however, should extend outwardly from the posts 14 in the terminal row 14a by a distance at least about one-half the height of the posts or between about of an inch and V2 of an inch for the illustrated embodiments.

With the projections 28 thus formed the stacked and nested filler flats 10 may be easily separated by raising one edge of the filler flat so that the projections 28 serve as an outwardly disposed fulcrum or pivot for the top filler flat, thus preventing the edge of the top filler flat at this pivot point from dropping or tilting into jamming engagement with the filler flat immediately therebelow, see FIG. 4. The projections 28 thus serve the dual function of spacing the stacked filler flats at the oppositely disposed edges and of facilitating the proper and unhindered denesting of the filler flats.

The projections, therefore, eliminate the problem of jamming of the stacked filler flat, although in some instances it may be desirable to distribute the compression load and spacing chore more uniformly over the tiller flat by providing additional means intermediate the oppositely disposed rows of projections 28 for maintaining the spacing between the nested intermediate portions of the filler fiat. This may be done by providing a shoulder 30, see FIGS. 3 and 5, in the underside of the posts adjacent the top thereof. This shoulder 30 may be formed by means of a finishing die which moves into engagement with the underside of the still wet filler flat on the screen form or mold just after the pulp has been drawn against the mold and before the wet filler flat has been ejected from the mold and sent to the drier. The formation of the shoulder 30 thus is not a matter of crowding fibers into a narrow fold in the screen form or mold as was the case in the formation of the projections 28, but this shoulder is formed by selectively compressing the top portion of each post in such a manner as will leave the shoulder portion of the posts uncompressed by the bottom forming or finishing die. Thus, when the filler flats it) have been dried and stacked in their nested relationship as illustrated in FIG. 3, the top of the posts of each underlying filler flat will engage and support the shoulder portion 24 of the corresponding post in the overlying filler flat.

Another means for achieving this spacing of the intermediate portions of the filler flat is illustrated in FIGS. 8 and 9. In this embodiment of the invention, the top parts 22a of at least some of the dividing portions 22 project above the upper edges of the pockets 12 and thus above the plane of the sheet in a manner such as suggested in Koppelman Patent No. 1,919,028. These upwardly extending parts are rendered solid as a result of drawing the pulp fibers into the narrow space between the folds of the screen form or mold at that point, and these solid parts extend between the adjacent posts 12 thereby adding a degree of rigidity to the entire filler flat structure. In addition, the solid parts 22a act as spacers for assuring that the desired spacing will be maintained between the nested intermediate portions of the stacked filler flats. This is best illustrated in FIG. 9.

In the embodiment illustrated in FIGS. 8 and 9 an interiorly disposed portion 31 of each post 14 in the terminal row 14a (except the center post which is usually a guide post) is angularly disposed with respect to both the top portion and the conical side portions of these posts. The angular disposition of this portion may be about 30 degrees with respect to the vertical or 60 degrees with respect to the plane of the sheet whereas the normal taper of the sides of the conical posts is 18 degrees with respect to the vertical or 72 degrees with respect to the plane of the sheet.

Still another modification of this intermediate spacing means is illustrated in FIGS. and 11. This modification consists in the formation of a narrow vertical solid web or lug 32 which diametrically spans the bottom of the pocket and extends upwardly from the bottom to a level which is below that occupied by an egg within the cup. These webs 32 engage the underside of the pockets in the overlying filler flat in the stack, as illustrated in FIG. 1'], and serve to assure that the intermediate nested portions of the stacked filler flats will be properly spaced to prevent any possible jamming of these portions.

Also in the embodiment illustrated in FIGS. 10 and 11, the projections 33 are of slightly diiferent configuration, and they are not connected to the sides of the posts in the terminal row as was the case with the projections 28 of the previously illustrated embodiments. However, the height, the outward positioning and the functions of these projections 33 are the same as for the projections 28.

From the foregoing it may be seen that filler flats constructed in accordance with this invention may be stacked and compressed for the most compact unit in shipment and storage and yet these filler flats may be easily separated and denested by the egg packaging plant. Denesting of each overlying filler flat may be accomplished by merely lifting one edge of that filler flat and permitting the outwardly extending edge projections 28 to act in unison as a single outwardly disposed fulcrum to assure that all nested portions of the overlying filler flat will be raised from the underlying filler flat even though only one edge of the overlying filler flat is being elevated. Thus, the denesting of the filler flats may become a onehand operation in the egg packaging plant.

Although the invention has been described with a certain degree of particularity, it is understood that the present disclosure has been made only by way of example and that many modifications and changes in various details may be resorted to without departing from the spirit and scope of the invention, as hereinafter claimed.

What is claimed is:

l. A molded pulp filler flat comprising a substantially flat sheet having a plurality of alternate rows of pockets and hollow posts extending from the plane of said sheet, a predetermined number of said hollow posts each having the interior thereof provided with a solid inwardly extending projection spaced from the upper end of said hollow interior, and a plurality of solid second projections extending upwardly from said sheet plane and disposed outwardly of a terminal row of posts; each of said second projections having at least a portion thereof disposed in closer proximity to the periphery of said sheet than to an adjacent post in said terminal row; said second projection portions being engageable with the underside of a filler flat arranged in superposed nested relation, and such nested filler flats being denestable when one of such flats is pivoted relative to the other about all of the engaging second projection portions acting as a fulcrum.

2. A molded pulp filler flat comprising a substantially flat sheet having a plurality of alternate rows of pockets and hollow posts extending from the plane of said sheet, a predetermined number of said pockets each having a solid projection extending upwardly from the bottom of said pocket, and a plurality of sol-id second projections extending upwardly from said sheet plane and disposed outwardly of a terminal row of posts; each of said second projections having at least a portion thereof disposed in closer proximity to the periphery of said sheet than to an adjacent post in said terminal row; said second projection portions being engageable with the underside of a filler flat arranged in superposed nested relation, and such nested filler flat being denestable when one of such flats is pivoted relative to the other about all of the engaging sec ond projection portions acting as a fulcrum.

3. The filler flat recited in claim 1 wherein at least said predetermined number of said hollow post-seach has an exterior configuration of a substantially truncated cone.

4. The filler flat recited in claim 1 wherein each second projection is elongated and extends fnom a post in said terminal row and is disposed tnansversely of said terminal row.

5. A molded pulp filler comprising a substantially flat sheet having a plurality of alternate rows of pockets and hollow posts extending from the plane of said sheet, adjacent pockets of each row being in spaced relation and adjacent posts of each row being in spaced relation, a plurality of solid first projections extending upwardly from said sheet plane and interconnecting corresponding sect-ions of certain of said adjacent posts, and a plurality of solid second projections extending upwardly from said sheet plane and disposed outwardly of a terminal row of posts; each of said semnd projections having at least a portion thereof disposed in closer proximity to the periphery of said sheet than to an adjacent post in said terminal row; said first and second projections being en- :gagcable with the underside of a like filler flat arranged in superposed nested relation; such nested filler flats being :denesta'ble when one of such flats is pivoted relative to the other about all of the engaging second projection portions acting as a fulcrum.

6. A molded pulp filler flat comprising a substantially flat sheet having a plurality of alternate rows of pockets and hollow posts extending from the plane of said sheet, and a plurality of solid projections extending upwardly from said sheet plane and disposed intermediate the pe ripheral edge of said sheet and a terminal row of posts adjacent thereto; each of said projections having at least a portion thereof disposed in substantially closer proximity to said sheet peripheral edge than to an adjacent post in said terminal row; said projection portions being engageable with the underside of a like fill-er flat arranged in superposed nested relation; such nested filler flats being denestable When one of such flats is pivoted relative to the other about all of the engaging projection portions acting as a fulcrumand said projection portions are in continuous engagement with the underside of such superposed flat during pivoting of one of such flats relative to the other to eifect denesting.

7. A molded pulp filler flat comprising a substantially fl-at sheet having a plurality of alternate rows of pockets and hollow posts extending from the plane of said sheet; a plurality of solid first projections disposed intermediate terminal rows of posts and adapted to engage surface portions of a like filler flat arranged in superposed nested relation; and a plurality of solid second projections extending upwardly from said sheet plane and disposed outwardly of a terminal row of posts, each of said second projections having at least a portion thereof disposed in substantially closer proximity to the periphery of said sheet than to an adjacent post in said terminal row and being engageable with the underside of such superposed filler fiat; such nested filler flats being denestable when one of such flats is pivoted relative to the other about all of the engaging second projection portions acting as a fulcrum, said second projection portions being in continuous engagement with the underside of such super- 2 8 posed filler fiat during such pivoting of one of such flats 2,347,658 Bourne May 2, 1944 relative to the other to effect denesting. 2,447,045 Amberg Aug. 17, 1948 2,997,196 Emery Aug. 22, 1961 References Cited in the file of this patent OTHER REFERENCES UNITED STATES PATENTS 5 Modern Packaging, Issue 1959, page 117, Article, 1,919,028 Hoppelman y 1933 Onicms in Thermoforms,

1,971,075 Lockwood Aug. 21, 1934 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent N0 3, 120,901 February 11; 1964 James William Boyd It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 6, line 12,, strike out "hollow"; column 6 line 18, after "filler" insert flat Signed and sealed this 30th day of June 19640 (SEAL) Attest:

ERNEST W; SWIDER EDWARD J. BRENNER AT testing Officer Commissioner of Patents

Claims

1. A MOLDED PULP FILLER FLAT COMPRISING A SUBSTANTIALLY FLAT SHEET HAVING A PLURALITY OF ALTERNATE ROWS OF POCKETS AND HOLLOW POSTS EXTENDING FROM THE PLANE OF SAID SHEET, A PREDETERMINED NUMBER OF SAID HOLLOW POSTS EACH HAVING THE INTERIOR THEREOF PROVIDED WITH A SOLID INWARDLY EXTENDING PROJECTION SPACED FROM THE UPPER END OF SAID HOLLOW INTERIOR, AND A PLURALITY OF SOLID SECOND PROJECTIONS EXTENDING UPWARDLY FROM SAID SHEET PLANE AND DISPOSED OUTWARDLY OF A TERMINAL ROW OF POSTS; EACH OF SAID SECOND PROJECTIONS HAVING AT LEAST A PORTION THEREOF DISPOSED IN CLOSER PROXIMITY TO THE PERIPHERY OF SAID SHEET THAN TO AN ADJACENT POST IN SAID TERMINAL ROW; SAID SECOND PROJECTION PORTIONS BEING ENGAGEABLE WITH THE UNDERSIDE OF A FILLER FLAT ARRANGED IN SUPERPOSED NESTED RELATION, AND SUCH NESTED FILLER FLATS DENESTABLE WHEN ONE OF SUCH FLATS IS PIVOTED RELATIVE TO THE OTHER ABOUT ALL THE ENGAGING SECOND PROJECTION PORTIONS ACTING AS A FULCRUM.