US3282458A

US3282458A - Nestable egg trays

Info

Publication number: US3282458A
Application number: US417651A
Authority: US
Inventors: Rudd Gerald Arthur
Original assignee: Diamond International Corp
Current assignee: Diamond International Corp
Priority date: 1963-12-24
Filing date: 1964-12-11
Publication date: 1966-11-01
Anticipated expiration: 1983-11-01
Also published as: GB1065848A

Description

NOV. 1, G A RUDD NESTABLE EGG TRAYS Filed Dec. ll, 1964 :3 Sheets-Sheet l INVENTOR G. A. RUDD Nov. 1, 1966 NESTABLE EGG TRAYS 5 Sheets-Shee 2 Filed Dec. ll, 1964 INVENTOR Km2. (L). `FLoc; rg

ATTORNEY G. A. RUDD Nov. 1, 1966 NESTABLE EGG TRAYS 5 Shees-Sheet 5 Filed Deo. ll, 1964 IDR/Of? ART INVENTOR ATTORNEY United States Patent O 3,282,458 NESTABLE EGG 'I'RAYS Gerald Arthur Rudd, Corton, near Lowestoft, Sulolk,

England, assigner to Diamond International Corporation, New York, N.Y., a corporation of Delaware Filed Dec. 11, 1964, Ser. No. 417,651 Claims priority, application Great Britain, Dec. 24, 1963, 50,934/ 63 4 Claims. (Cl. 217-265) This invention relates generally to packages used in storing, handling, and shipping eggs and like ovate articles, and is more particularly related to improvements in nestable trays which include means `for not only protecting the articles being packed lbut also include means whereby the trays may be readily nested and denested to facilitate all of the advantages of production-line handling and packing of packages.

It Ihas heretofore, and still is, the co-mrnon custom to pack eggs for shipment in corrugated cases or wooden crates in which paperboard fillers and flats 'are used, each flat having cells for receiving the individual eggs and the fillers separating the individual eggs.

Combination filler flats or trays of the character involved in the present invention are ygenerally produced from a fiber material, ie., are mass-'produced on machines carrying suction dies, which are passed during operation through a suspension or slurry of fibers, whereby the latter are deposited in the form of a felt on the surface of the die in a layer.

The deposited fibers, which are initially suspended in fluid, generally provide for a suitable softness andV resilience, however, the requisite strength, cell capacity, etc., is achieved through the use of specific structural components and design of the cells.

The trays or filler ats must be so strong that they can support the eggs when being lifted at opposite edges, i.e., most conventional trays including recesses to form hand grip portions on two opposite sides.

An object of the present invention is to provide a molded tray produced from a molded pulp or papiermache which includes means for preventing jamming of the trays when they are nested one within the other for storage, shipment or denesting from automatic equipment 'and yet permitting the nested trays to be readily separated without tearing or destroying portions of the trays.

Another object of the present invention is to provide in a tray of the character mentioned above, a plurality of equi-spaced .support posts arranged in longitudinal and transverse rows extending upwardly `from a bas'e p'llane wherein intermediate rows of posts depend from the base plane and define egg-containing cells or pockets with -the support posts, and in which adjacent support posts are interconnected by rect-angularly arranged ribs combining to form a partial side wall enclosure `for the cells or pockets and to define each cell in a :general-ly rectangular pattern with a support post at each corner.

A `further object of the present invention is to provide in a tray of the character -set forth .above support posts -which may geometrically lbe described as formed by revolving a curved line about `a vertical axis with the curve being concave on the side away from said axis, thus having an outer concave wall land which also generally terminates in a lateral land and in which the sides of Vthe cells or pockets may Ibe Igeometrically described as Patented Nov. .l l 966 ice being formed by revolving a compound curve of varying radii and having an outer concave wall terminating in said lateral land.

Another object is to provide a tray wherein the inner surface Iof each cell preferably has an upper portion extending upwardly :and outwardly so that la tangent to said upper portion is substantially at an angle of 20 to the vertical 'axis of said cell and a lower portion eX- tendin'g downwardly and inwardly so that la tan-gent to said lower portion is substantially at an angle of 30 to said axis.

Another object is to provide a tray wherein the surface of each cell therein is curved continuously over its whole height or it may have portions which are straight or substantially straig-ht in vertical section (e.g., at the top `and bottom of the surface), provided that said portions are merged smoothly in a curve, in vertical section, with the remainder of the surface. v

Another object is to provide a tray wherein support posts lare `so formed and spaced .as to present a relatively large opening facilitating smooth entry of eggs into depending cells and wherein the cells have la concave int'erior surface of compound curvature to accommodate different size elggs and provide a large support area and a convex underside to circumferentially contact the upper portions of eggs supported in cells of `a similar tray below the first-mentioned tray, said surface having a concave interior and a convex underside being generated by revolving a compound curve.

Another object is to provide a tray including depending cells having a substantially rectangular base configuration and including upwardly extending support posts having a circular top configuration so that when the trays are stacked ione upon another when loading a case or crate the `bottoms of depending cells will engage upper terminal portions of the support posts to provide proper transmittal of vertical load therethrough.

And yet a still further object of the present invention is to provide in a tray of the character mentioned, articlecontaining cells or pockets formed by means of =a plurality of spaced stiffening ribs projecting outwardly from the inner face of the pockets fand upwardly from the bottom of an :associated pocket to approximately midway of the height of said cells or pockets, said ribs being spaced about the circumference of an associated post and .generally comprising four stifiening ribs each of which having an outer configuration substantially distinct and difieren-t from a downwardly opening recessed or associated pocket therebeneath, whereby .the ribs not only strengthen the lassociated post lagainst collapse during `nesting of th'e trays, but also reinforce the post so asl to provide strength to the trays when they are lifted with the cells loaded with eggs, -and also provide for increased strength for the transmittal of vertical 'loads in or through a stack of loaded trays.

These together with other and more specific objects and Iadvantages of the invention will be understood from a consideration of the following description when taken in conjunction with the drawings forming a part thereof, whe-rein:

FIG. l is a plan view of an egg tray embodying the features of the invention;

FIG. 2 is an end elevation looking inwardly at the lower edge of FIG. l, as indicated by the direction arrow identified as A;

ansa/ree FIG. 3 is a vertical section taken substantially on the planes of line 3 3 of FIG. l;

FIG. 4 is a side elevation taken ysubstantially from right to left at FIG. l as indicated by th'e direction arr-ow Ilabeled B;

FIG. 5 is yan enlarged fragmentary section taken substantially `on the plane of line 5 5 of FIG. 1 and showing more specifically exact details and the configuration of one of the tray cells;

FIG. 6 is an enlarged fragmentary section tak'en substantially on the plane of line 6 6 of FIG. l, showing details of *the novel rib construction 'and configuration of the support post about which cells are formed;

FIG. 7 is :an essentially diagrammatic view showing a pair of trays in juxtaposed relation wherein the upper tray has been rotated 90 and juxtaposed on the lower tray for illustrating the egg-receiving areas formed between the egg-receiving cells of the bottom tray, and the corresponding egg-receiving portions afforded by the undersurface of the uppermost tray;

FIG. 8 is a diagrammatic view illustrating theoretically how a plurality of eggs are received in the cooperating egg-receiving portions of juxtaposed trays;

FIG. 9 is a fragmentary section showing the nesting of two tray portions and illustrating the manner in which portions of the egg tray ribs nest and facilitate ready denesting;

FIG. 10 is an enlarged fragmentary view of a portion of FIG. 8 more clearly illustrating the support surfaces afforded by an egg-receiving space between la pair of juxtaposed cooperating trays; and

FIG. 1l is a diagrammatic view, similar to FIG. l0, showing the theoretical supp-ort surfaces afforded by true conical egg-receiving cells and similar cooperating portions of the undersurface of such a tray juxtaposed thereon.

Referring to the drawings in detail, it will be understood that the egg tray of this exemplary embodiment is a substantially rectangular orsquare sheet 0f fiber mass which is generally mass-produced on machines carrying suction dies, which dies are passed during operation through a suspension of fibers, whereby the fibers are deposited on the surface of a die.

The tray to presently be `described in ldetail is that of the type conventionally 'described as a 5 x 6, i.e., will hold thirty eggs or two and one-half dozen eggs. Inasmuch as the novel cells and other cooperating portions of the tray are substantially duplicated throughout thev tray, only one of the cells and posts will be described in detail.

A tray is indicated generally at 10 and comprises a rectangular one-piece body member 12 produced as a single sheet lof fiber mass and having a peripheral marginal flange 14 substantially bordering all sides thereof with the exception of indented or

hand grip portions

16 and 18 at opposite sides thereof. The peripheral fiange 14 defines a base plane from which other cooperating portions of the tray will be related and identified.

The body member 12 includes a plurality of pockets or cells indicated generally at 20 produced in rows extending crossvvise and lengthwise of the sheet, equally spaced apart from one another and forming a regular pattern. Between these pockets there `are provided projections indicated generally at 22 which follow a similar pattern. The projections or posts 22 are interconnected by horizontally disposed and circumferentially spaced ribs 24 disposed at 90 intervals.

Details of the cells, posts and horizontally disposed ribs will be subsequently described, particularly with respect to FIGS. 3-6. In the 5 x 6 tray, six posts in a row extend in one direction, and five posts in a row ex` tend normal thereto. Halfposts are provided adjacent the direction in which the five posts in a row extend, and these half-posts are indicated at 26. Additionally, as indicated at 28, half-cells are formed at opposite ends of the tray in which a row of five cells appear. The halfposts and halfcells will not be described in detail.

Referring to FIGS. 2-6, and particularly considering the ribs 24, it will be noted that these ribs have generally what might be described as a Wishbone or inverted Y shape and have a substantially rectangular but bulbous top portion 30 which is produced from a build-up of the fibers from which the tray is produced. In this relatively confined and narrow 'area of the lsuction die, as pulp is initially sucked into this area, fibers will pile up or be of a built-up character, i.e., the fibers piling upon each other and bridging across. Though the recess in the die for forming the portion 30 i-s rectangular with parallel sides, owing to differential shrinkage on drying, the

sides

32, 34 become undercut in the final product as illustrated in FIG. 6. lThus, the portion 30, when viewed in section as in FIG. 6, has a bulbous top, inwardly tapered sides which continue into a pair of

diverging legs

36 and 38 which form a downwardly opening substantially inverted V-shaped nesting groove 40 extending the length of the horizontally disposed ribs for overlying the similar rib of a tray which is nested below that of the character shown in FIG. 6, for example (see FIG. 9). The tray horizontally disposed rib, which will be nested in the groove 40, will have an upper configuration of the character shown at 30in FIG. 6, and thus jamming or impaction of nested trays will be prevented. The upper edge of the ribs 24 will be disposed a distance S from the upper surface of the peripheral flange 14 to the upper edge of such ribs, 'and this provides a denesting spacing to prevent the similarly conformed posts and depending cells of juxtaposed trays from becoming impacted and difficult to separate. The ribs are solid in cross section, i.e., are undercut from the upper edge, and have a width or cross section substantially greater than the normal thickness ofthe blank.

The

legs

36 and 38 extend laterally in

foot portions

42 and 44 which are connected to downwardly diverging

wall portions

46 and 48 comprising portions of the cells 20.

The posts 22 project above the base plane defined by the peripheral flange 14 and comprise ya concave surface generated by an inwardly extending compound curve revolved about a vertical axis, i.e., the posts 22, when viewed in elevation as seen in FIGS. 5, 6 and l0, for example, have a concave outline when viewed in vertical section, as indicated at 50. The oute'rside of the posts 22 have been described as having a concave surface and thus it will be understood that the underside of the posts 22 is substantially in the form of a corresponding surface of revolution generated by a convex curve. The interior surface of each cell has a section which is smoothly curved and concave in vertical section, as illustrated, for example, in FIGS. 5, 8 and l0. The lower portions of the inner surface of each cellextends downwardly and inwardly so that a tangent thereto is at an angle of substantially 30 to the vertical axis of the cell while the upper portion of the inner surface of each cell extends upwardly and outwardly so that a tangent thereto is at an angle of 4substantially 20 to said axis. In this Way, the part of the inner surface of each cell which will be engaged 4by an egg is given the desired general inclination while the required height of the posts is obtained. The concave inner surface of each cell will engage a larger area of Contact with the convex surface of an egg, thus more firmly and safely supporting the egg. The steeper upper wall portion of the cell provides greater resistance to collapse under vertical load than if the Whole wall was, like the lower portion thereof, less steeply inclined. The tray in accordance with the invention can be used for eggs of different sizes and the configuration of the tray is such that the cubic capacity of the egg case or egg tray within which the loaded trays are stacked is efficiently utilized.

The ycells 20 have circumferentially spaced thereabout vertically extending flutes 54 which facilitate the production of the cel-ls 20 with a substanti-ally rectangular base 56. rIlhis rectangular base, it will -be observed, has extending from each of the corners thereof one of the flute-s 54 which merge into the side of the post 22 and, accordingly, reinforce the same.

The cells 20 are defined at their uppermost portion by a circumferential flange or land 5S comprising portions of the

feet

42 and 44 previously mentioned with respect to the ribs 24. It will be noted that the

legs

36 and 38 disposed on opposite sides ofthe downwardly opening -groove 40, converge upwardly from the flange or land 58. Further, the terminal ends of the ribs extend integrally with an intermediate portion of the side surfaces of the posts 22.

It will be observed in FIG. 5, for example, that the reverse or inner side of the portions 50 of the post 22 having a concave surface 60, this portion having a delinite function with respect to the upper portions of eggs stored in an egg-receiving space R as indicated in FIGS. 8 and 10.

Considering FIG. 7, a tray of the character disclosed lin FIG. l will receive in the cells thereof eggs, and a second t-ray indicated at 10 will be positioned thereon; however, it will be rotated 90, i.e., the hand-receiving

portions

16 and 18 will be disposed at 90 with respect to each other on the respective tray-s, as is conventional. When the trays are so oriented, the rectangular bottom surface of the cell bottom 56 will be received on the upper circular end portions of the underlying posts 22. Since the 'bottoms of the cells are rectan-gular, they have a slightly greater area than the upper end portions of the posts 22, and thus, though the trays may shrink nonuniformly, engagement between the posts will be substantially assured.

Referring to FIG. 8, the egg-receiving spaces R comprise the lower concave surface 52 and the undersurface or convex surface 60 of the posts, i.e., the lower surfaces oppo-site the surfaces 50.

A-s illustrated essentially diagram-matically in FIGS. 8 and 1l, eggs are conventionally packed small end down and the lower concave portion of the cells 20 will provide a support surface which is relatively broad, inasmuch as the concave portion will, in a sense, conform or be complementary to a corresponding portion of the side surface of the eggs. In a sense, a relatively broad support area C is provided for the lower portions of the eggs. However, the convex upper portion of the eggreceiving portions of a pair of cooperating trays will have substantially circumferential, linear or tangential engagement, as indicated at T, i.e., a line extending circumferentially about the upper larger portion of the eggs due to tangential contact with the convex portions 60 of the cells.

Referring to FIG. l1, there is disclosed a theoretically true frustum of a cone generated by rotating a right triangle about a spaced vertical axis, as indicated at F. In other words, when the sides of the cells are substantially straight in vertical section, -there will only be two lines of contact L, L with the respective upper and lower portions of the egg being contacted in the egg-receiving space R.

Referring to FIG. 9, a lower tray 10 has nested thereon a tray 10 and the cooperating relationship of the lower -rib 24 with respect to the upper lrib 24' is illustrated. It wil-l be noted that the space 40 formed above the legs 36', 38 will receive the llower -rib 24 therein, thus preventing the posts and cells of nested trays from becoming impacted to .prevent subsequent denesting.

Thus, there has been disclosed an egg packing tray or filler-flat which in itself has egge cells or pockets afforded by a side wall enclosure in a generally rectangula-r pattern and the side wall enclosure is integral with and extends from intermediate -surface portions of vertical support posts. This construction includes the ribs which are relatively solid and generally rectangular, though provided with a bulbous head and undercut sides, in cross section and also includes the depending legs or Iside wall portions terminating in lateral feet coinciding with an upper flange defining the upper edge of egg-receiving cells which are disposed substantially below a base plane defined by a peripheral ange of the tray. This construction facilitates `the lifting of a tray loaded with eggs by providing integral beams surrounding each of the cells filled with eggs.

When a shipping case is filled by a plurality of the disclosed egg trays to form egg-receiving spaces of the character described, the lower square por-tions of the `cells will have intimate contact with the upper ends of the posts of an underlying tray to accordingly provide transmittal of vertical load or forces through the trays to the bottom of the packing case or support surface without imposing -load on the eggs packed between juxtaposed trays. Additionally, due to the inner concave support surface of the cells and the reverse convex surface of the egg-receiving space formed by juxtaposed trays, the eggs are maintained in the cells in a relatively xed position to prevent rattling, etc.

When the trays per se are stored, lshipped or disposed in mechan-ical denesting apparatus, the rectangularly and horizontally disposed ribs surrounding each of these cells will not only reinforce the trays a-gainst damage, hut will facilitate ready denesting of one tray from another.

It will be obvious to those skilled in the art that various change-s may be made without departing from the scope of the invention and therefore the invention is not limited t-o what is shown in the drawings and described in the specification but only as indicated in the appended claims.

What is claimed is:

1. A molded pulp tray comprising a body member having a generally normal thickness and including a peripheral margin defining a base plane, said body member including a plurality of hollow posts extending vertically lfrom said lbase plane and a plurality of hollow cells depending from said l1base plane, said posts 'being alternately disposed in transverse rows, said body member including ribs spaced in intervals about said posts yand connecting certain of said posts to each other, said ribs including a linear upper edge disposed in a plane above said base plane and extending continuously lbetween said posts, the improvement characterized in that said ribs have an upper vbulbous solid portion of larger cross section than, and converging downw-ardly into, the portion of the ribs therebeneath and substantially thicker than the normal thickness of said body member and integrally formed with pairs of legs of normal thickness disposed below said Ibase plane and diverging in a downwardly opening groove disposed below said base plane and extending the length of said ribs and having a concave cross section distinct from said solid =bulbous rib portions and extending upwardly into the base of said ri-bs for preventing impaction of nested trays and permitting ready denesting therebetween, said legs terminating in lateral foot portions disposed in a plane below said base plane, said foot portions being connected to downwardly diverging side wall portions of said cells whereby when at least a pair of trays are nested only the juxtaposed upper edge portion of the ribs of the lowermost tray is engaged with side wall -portions of the grooves of the uppermost tray.

2. A tray according to claim 1 characterized in that the outer surface of said hollow posts and the inner surfaces of said pocket formations effectively provide the upstanding vertical posts and hollow cells and include a shape corresponding to a surface generated by revolving a compound curve about the vertical axis of said cells and are uniformly concave from the top of said posts to the Ibase of said cells wit-h respect to the vertical axis of these cells.

3. A tray according to claim 2 characterized in that a line tangent to the upper portion of said posts is substantially 20 with respect to the Vertical axis. of the posts and a line tangent to the walls of the cells Ais at substan- 11/1916 Eaid 217-265 r 5/1937- Dorf .217 26.5 L

8 ,Beck 217-265 Putnam 217-265 Millett 229-25 Grant 217-265 Emery 217-265 Martelli et al. 229-25 Boyd 217-265 Whiteford 229-25 Hartmann et al. 229-25 Reifers et al. 217-265 THERON E. CONDON, Primary Examiner. RAPHAEL H; SCHWARTZ, Examiner.

Claims

1. A MOLDED PULP TRAY COMPRISING A BODY MEMBER HAVING A GENERALLY NORMAL THICKNESS AND INCLUDING A PERIPHERAL MARGIN DEFINING A BASE PLANE, SAID BODY MEMBER INCLUDING A PLURALITY OF HOLLOW POSTS EXTENDING VERTICALLY FROM SAID BASE PLANE AND A PLURALITY OF HOLLOW CELLS DEPENDING FROM SAID BASE PLANE, SAID POSTS BEING ALTERNATELY DISPOSED IN TRANSVERSE ROWS, SAID BODY MEMBER INCLUDING RIBS SPACED IN 90* INTERVALS ABOUT SAID POSTS AND CONNECTING CERTAIN OF SAID POSTS TO EACH OTHER, SAID RIBS INCLUDING A LINEAR UPPER EDGE DISPODED IN A PLANE ABOVE SAID BASE PLANE AND EXTENDING CONTINOUSLY BETWEEN SAID POSTS, THE IMPROVEMENT CHARACTERIZED IN THAT SAID RIBS HAVING AN UPPER BULBOUS SOLID PORTION OF LARGER CROSS SECTION THAN, AND CONVERGING DOWNWARDLY INTO, THE PORTION OF THE RIBS THEREBENEATH AND SUBSTANTIALLY THICKER THAN THE NORMAL THICKNESS OF SAID BODY MEMBER AND INTEGRALLY FORMED WITH PAIRS OF LEGS OF NORMAL THICKNESS DISPOSED BELOW SAID BASE PLANE AND DIVERGING IN A DOWNWARDLY OPENING GROOVE DISPOSED BELOW SAID BASE PLANE AND EXTENDNG THE LENGTH OF SAID RIBS AND HAVING A CONCAVE CROSS SECTION DISTINCT FROM SAID SOLID BULBOUS RIB PORTIONS AND EXTENDING UPWARDLY INTO THE BASE OF SAID RIBS FOR PREVENTING IMPACTION OF NESTED TRAYS AND PERMITTING READY DENESTING THEREBETWEEN, SAID LEGS TERMINATING IN LATERAL FOOT PORTIONS DISPOSED IN A PLANE BELOW SAID BASE PLANE, SAID FOOT PORTION BEING CONNECTED TO DOWNWARDLY DIVERGING SIDE WALL PORTIONS OF SAID CELLS WHEREBY WHEN AT LEAST A PAIR OF TRAYS ARE NESTED ONLY THE JUXTAPOSED UPPER EDGE PORTION OF THE RIBS OF THE LOWERMOST TRAY IS ENGAGED WITH SIDE WALL PORTIONS OF THE GROOVES OF THE UPPERMOST TRAY.