US 3373921 A
Description (OCR text may contain errors)
March 19, 1968 w. B. CRANE 3,373,921
' SHIPPING CONTAINER Filed'Nov. 17, 1966 5 Sheets-Sheet 1 2 v INVENTOR WALTON B. CRANE March 19, 1968 Filed Nov. 17, 1966 W. B. CRANE SHIPPING CONTAINER 3 Sheets-$heet lib-L;
WALTON B. CRANE INVEN TOR ATT'YS.
March 19, 1968 w. B. CRANE 3,373,921
SHIPPING CONTAINER Filed Nov. 17, 1966 3 Sheets-Sheet 5 -31 has IN VENfOR Cg WALTO/V B. CRANE United States Patent tion of California Filed Nov. 17, 1966, Ser. No. 595,097 14 Claims. (Cl. 229-23) This invention relates to tray-type containers and is more particularly concerned with improvements in produce shipping containers which are fabricated in part from a relatively inexpensive material, preferably corrugated paperboard, yet which are so constructed that they have adequate strength and rigidity and aiford suflicient resistance to crushing when a multiplicity of the filled containers are stacked in vertically disposed relation for ship ment, storage or the like.
In the handling of certain products, for example fresh produce such as grapes or the like, shipping containers fabricated from corrugated paperboard stock have become increasingly popular. Numerous forms of such containers have been developed in an effort to meet the relatively high standards of rigidity and resistance to bowing and crushing of the walls which are necessary in view of the conditions under which the containers are used and to keep the cost of the containers low enough to compete with the wooden crates which they are intended to replace. Many paperboard containers previously developed have not proven satisfactory in use because of insufficient wall strength. When weakened by moisture absorption, as frequently occurs when the containers are stacked in the field prior to use in areas where there is considerable moisture, or when they are subjected to humidified cold storage conditions for a substantial period of time, the side and end walls of the container give way resulting in damage to the contents. The problem has been particularly severe when such containers are stacked in filled condition, as is essential for eflicient storage and shipment.
Efforts to increase the strength of the previous paperboard containers by providing multiple thicknesses of material in the walls have not been successful. Among other things, this is because of increased costs due to the extra blank material required for adequate reinforcing makes it difficult for the containers to compete with containers furnished for this purpose which are manufac tured of wood or other more rigid materials.
A general object of the present invention is to provide an improved, low-cost container fabricated largely from a relatively inexpensive material, such as corrugated paperboard, yet which has adequate strength and rigidity and is especially adapted for the efiicient handling and storage of produce such as grapes.
It is a more specific object of the invention to provide a tray-type shipping container or produce crate which has 'been especially devised for the efiicient shipment and storage of grapes and is also well suited to handle other equally and even more perishable commodities, which is fabricated in part from corrugated paperboard stock, with an improved and reinforcing structure employing a stronger and more rigid material, and which container may be produced at a cost sufficiently low to permit it to compete with the widely used wooden lug which it is intended to supplant.
It is a further object of the invention to provide a traytype produce shipping container which is adapted to be fabricated from a single blank of reinforced corrugated paperboard with end members of stronger and more rigid material, such as plastic, shaped in the form of a panel and adapted to co-operate with end panels and corner connecting flaps on the blank so as to form a rigid end 3,373,921 Patented Mar. 19, .1968
structure with a high degree of resistance to crushing under vertical load when the filled trays are stacked for shipment and/ or storage.
Another object is to provide a tray-type shipping container which is fabricated in part from a relatively lowcost sheet material with end frame members of a stronger and more rigid material, and which embodies centering and interlocking lugs and co-operating recesses at th top for holding adjacent containers, when disposed in stacked relation, against relative lateral shifting.-
It is another object of the invention to provide a traytype produce shipping container fabricated from a single blank of corrugated paperboard material and end frame members of plastic which are specially designed for securing to the edges thereof portions of the corrugated paperboard material and also recesses on the outer faces to accommodate end wall panels hinged to opposite ends of the bottom wall panel and corner connecting flaps hinged to opposite ends of double thickness side walls, with the panels, connecting flaps and end frame members bonded together so as to form a rigid end wall structure having adequate strength to prevent crushing when a substantial number of the containers are filled and assembled in stacked relation.
A still further object is to provide an improved con tainer of the type described which is especially well suited for having printing, such as advertising and identifying symbols, applied to it.
These and other objects and advantages of the invention will be apparent from a consideration of the produce container which is shown by way of illustration in the accompanying drawing wherein:
FIGURE 1 is a perspective view of a tray-type container especially designed for use as a grape lug which has incorporated therein the principal features of the invention;
FIGURE 2 is a perspective view showing one end of the container in partially assembled condition;
FIGURE 3 is a top plan view of a corrugated paperboard blank employed in fabricating the present container;
FIGURE 4 is an elevational view showing the outside face of a plastic end frame member employed in fabricating the present container;
FIGURE 5 is a partial section taken on the line 5-5 of FIGURE 1 on an enlarged scale;
FIGURE 6 is a perspective view of the container unit of FIGURE 1 with a lid member partially installed;
FIGURE 7 is a view in end elevation illustrating the manner in which the container may be stacked; and
FIGURE 8 is a fragmentary cross section taken on the line 88 of FIGURE 7 on an enlarged scale.
Referring to the drawings, there is illustrated, by way of example, a tray-type container which embodies the principal features of the invention and which is especially adapted to be employed in the harvesting, handling, storing and/ or shipping of grapes and similar produce.
The tray-type container 10 which is illustrated in the drawings and which is commonly referred to as a shipping lug or crate is fabricated from a blank 11 of corrugated paperboard or other similar, relatively inexpensive sheet material and a pair of frame-like end forming members 12 which are of identical construction and which are of a stronger and more rigid material, preferably a plastic, such as polystyrene or polypropylene. These members 12 afford the assembled container with the desired strength and rigidity, while, at the same time, enabling a relatively inexpensive material such as paperboard, to be used to form the greater part of it.
The board blank 11 which is of generally rectangular shape is cut and formed with a plurality of fold lines or zones of weakness, as by scoring or creasing, as illustrated in FIGURE 3. The blank 11 is symmetric about longitudinally and transversely extending medial lines indicated at a-a and bb, respectively. For simplicity, the same reference numerals will be employed to designate corresponding parts and/ or relationships on one side of the medial line b-b while the same numerals primed will be employed to designate like parts on the opposite side of the medial line b-b.
The blank 11 is divided by transversely extending, parallel, longitudinal fold lines 13 and 13 into a central bottom and side wall forming section 14 and end wall and corner connecting flap forming sections 15 and 15 at opposite ends of the blank.
The bottom and side wall forming section 14 (FIGURE 3) of the blank 11 is subdivided by parallel, longitudinally extending, transversely spaced fold lines 16 and 1 6' to provide a bottom wall forming center panel 17 and identical side wall forming panel portions are further divided by transversely spaced fold lines 18, 18' and 19, 19' which are parallel with the fold lines 16 and 16' and which divide these portions of the blank into bottom side wall panels 20, 20', top side wall panels 21 and 21' and top side wall reinforcing panels 22 and 22' which are separated from each other by the hinge forming fold lines 18, 18' and 19, 19'. In some instances, it may be desirable to provide the reinforcing panels 22 and 22 at their outermost edges with pairs of small glue tabs 23 and 23 adjacent the opposite ends thereof. For purpose of ventilation, the bottom side wall panels 20 and 20 are each provided with a series of apertures 24 and 24'.
The end wall and corner connecting sections 15 and 15 of the blank 11 are cut in an identical manner to provide end wall panels 26 and 26' and corner connecting panels or flaps 27 and 27 which extend from opposite ends of the top side wall panels 21, 21' and which are adapted to hinge on the lines 13 and 13'. When the container 10 is assembled, as in FIGURE 1, the panels 26 and 26 are disposed on the outer ends and are well suited for displaying advertising and identifying symbols. By virtue of the panels 26 and 26 being formed of paperboard, printing may be easily accomplished. The side wall reinforcing panels 22 and 22 are adapted to be folded over and adhesively secured in face-to-face engagement with the inner face of the adjoining side walls panels 21 and 21' prior to assembling the blank with the end forming members 12 in setting up the crate, as indicated in dot-dash lines in FIGURE 3. The glue tabs 23 and 23, in the event they are used, are brought into overlying relation with portions of the lower side wall panels 20 and 20' and are adhesively secured thereto.
The frame-like end members 12, as shown in FIGURES 1, 2 and 4, are of identical construction and are formed of a rigid plastic material configurated so as to provide a web-like body portion 30 and a peripheral flange 31. As noted above, the end frame members 12 serve the important purpose of affording the assembled container with the desired strength and rigidity. They are constructed and arranged so that when a number of like containers are vertically stacked, the weight of the above containers is supported totally by end members 12. To accomplish this end, each of the members has a compressive strength substantially greater than that of the blank 11. This strength is provided both by reason of the members being made of plastic and by reason of their shape. The particular member illustrated is also advantageous from the standpoint of making efiicient use of the plastic material. Moreover, it readily lends itself to forming by economical methods, as by injection molding.
To enhance the strength of the container and to provide a good support surface for adjacent containers, when stacked in the manner of FIGURE 7, the peripheral flange 31 is of substantial width. It extends along the top and bottom of each member 12 and, preferably, as illustrated} extends entirely around it.
The body portion 30 of each of the members 12 is divided into a central section 32 with vent apertures 39 and two identical end sections 33 and 33', the center section 30 being in a common plane with the inside edges of the peripheral flange 31 while the end sections 33 and 33 are offset relative to the center section 32 so that they are in a common plane with the outside edge of the bottom portion 34 of the flange 31 and inset relative to the top portion 35 of the flange 31 a distance corresponding approximately to the thickness of the material in the end panels 26 and 26' of the blank. Marginal portions 36 of the flange section 35 overhang and protect the top edge of the associated end panel 26 or 26', when the container is assembled.
The member 12 is formed with the corners along diagonal lines diverging from a longitudinal center line and the overhanging margin 36 of the flange portion 35 extends along the top corners of the member so as to protect the entire top edge of the panel 26 or 26. The end sections 33 and 33 of the body of member 12 are formed with shallow recesses 37 and 37 extending lengthwise of the member 12 and of a size and shape corresponding approximately to the size and shape of the corner connecting flaps Mind 27 at each end of the blank 11 so that the latter may be snugly seated therein (FIGURE 2). The body sections 33 and 33' are slotted horizontally as shown to reduce the amount of plastic material required, while the center section 32, as previously noted, is provided with the vent apertures 39 comprising two rows of vertically disposed slots which also have this advantage.
It is desirable when the containers are stacked that they be interlocked or held against relative lateral shifting. This interlocking is achieved by a pair of generally L-shaped protuberances or centering lugs 40 that extend upwardly of the top flange portion 35 and are adapted to be received in a pair of apertures 41 formed in the bottom portion 34 of the flange 31 and extending somewhat into the center section 32 of the body of the member 12. The blank 11 is provided with slots 25 (FIGURES 3 and 5) in the bottom wall forming panel 17 in order to enable the lugs 40 to pass through such panel. The apertures 41 are spaced to accommodate the lugs 40 and co-operate therewith in centering the units when they are stacked as illustrated in FIGURE 7. Referring to FIGURE 5, it may be seen that a small flange or rib portion 42 extends between the apertures 41 and projects downwardly of the flange portion 34 so as to be received in the aperture 25 in the bottom wall panel 17, serving to locate the member 12 in proper position for assembly with the blank 11 in setting up the container.
In some applications, it may be desirable to provide the container with a detachable lid 45 illustrated in FIG- URE 6. For mounting the lid 45, inwardly extending pairs of spaced protuberances 43 and 43' are formed in the upper portions of the end sections 33 and 33 of the end member 12 so that each provides a shelf 44 (FIGURE 8) spaced from the bottom face of the flange portion 35. This shelf 44 is adapted to accommodate a marginal end portion of the lid 45 which, as shown in FIGURE 6, comprises a rectangular sheet of corrugated board slotted at its opposite ends at 46 and 46', so as to accommodate the center section 32 of the end members 12.
In setting up the illustrative container, a suitable adhesive is applied to the inside faces of the side wall reinforcing panels 22 and 22' and they are folded inwardly onto the top side wall panels 21 and 21' and secured thereto as indicated in phantom lines in FIGURE 3. The end members 12 are positioned at each end of the blank 11 at substantially right angles to the bottom wall forming panel 17 with the locating flanges 42 seated against the inside edges defining the slots 25 and 25 and with the members extending along the hinge lines 13 and 13.
Following positioning of the end members 12, adhesive is applied to the corner connecting panels or flaps 27 and 27 and the latter are folded into the recesses 37 and 37' in the outside faces of the end members 12 to the positions shown in FIGURE 2 and secured therein. The side wall panels 20, 21 and 20', 21' are simultaneously folded or hinged about the score lines 16, 18 and 16, 18 into side wall forming position. Adhesive is next applied to the inside faces of the end well forming panels 26 and 26, as at 46 in FIGURE 2, and the latter panels are folded or hinged about the lines 13 and 13 into engagement with the outside faces of the end members 12. As is apparent, the end wall forming panels 26 and 26 may be secured either directly to the end members 12 or to the flaps 27 and 27' which, in turn, are secured to the members, or to both. In addition, to enhance the strength of the container 10, other confronting surfaces of the blank 11 and end members 12, such as the marginal ends of the side wall panels 22 and 22' and the adjacent portions of the peripheral flange 31 may be adhesively secured to one another.
The container formed in the manner described has rigid reinforced end walls which offer substantial resistance to crushing when the loaded containers are stacked for storage or shipment and double ply reinforced side walls of sufficient strength and rigidity to withstand the stresses resulting from normal usage encountered in the field and in shipping and storing. Venting of the interior of the container is achieved by the vent apertures 24 and 24 in the side walls and the apertures 39 in the central sections 32 of the end members 12. In the latter connection, it will be noted that air spaces (FIGURES 2 and 5) are provided between the end wall panels 26 and 26 and the central sections 32 of their associated end members 12, with passage between such spaces and its exterior being provided through the apertures 41.
While particular materials and specific details of construction have been referred to in describing the form of the crate illustrated, it will be understood that other suitable materials and equivalent structural details may be resorted to within the spirit of the invention.
1. A tray-like container which is fabricated from a blank formed of a relatively thin sheet material and a pair of rigid end frame members, each of which has a compressive strength substantially greater than that of said blank, said blank providing a bottom wall forming panel and side wall forming panels which form, when the container is set up, a bottom wall and side walls connected to the side edges of the bottom wall, said end frame members each having planar surfaces of substantial widths along at least portions of its top and bottom edges and said end frame members being positioned, one each, at opposite ends of said bottom wall forming panel at substantially right angles thereto with the bottom edge surfaces in engagement therewith and projecting upwardly therefrom at substantially right angles, connecting panel means connected to said side wall panels at the opposite ends of said blank and end panel means connected to said bottom wall forming panel at the opposite ends thereof, said connecting panel means and said end panel means at each end of said blank being disposed in overlying relationship with the associated one of said frame members, and means securing said connecting panel means and said end panel means in such relationship to the associated one of said end frame members, whereby the Weight of a plurality of like containers, when disposed in stacked relation, is supported by said end frame members.
2. A tray-like container as recited in claim 1, and said blank is an integral member formed of paperboard.
3. A tray-like container as recited in claim 1, and cooperating interlocking means provided at top and bottom edges of said end frame members for holding like containers against relative lateral shifting when disposed in stacked relation.
4. A tray-like container as recited in claim 1, and an integral protuberance projecting upwardly from said surface at said top edge of each said frame member and a correspondingly shaped recess in said bottom edge of each said frame member.
5. A tray-like container as recited in claim 1, and a lid, and means on said end frame members below said top edge surface for receiving the marginal edges of said lid for detachably mounting the same.
6. A tray-like container which is fabricated from a blank formed of a relatively thin sheet material and a pair of rigid end frame members, said blank providing a bottom wall forming panel and side wall forming panels which form, when the container is set up, a bottom wall and side walls hinged to the side edges of the bottom wall, said frame members each having a Web-like body forming panel within a peripheral flange of substantial width which is in a plane approximately normal to the plane of the body forming panel, said body forming panel having a center section and end sections with the end sections extending approximately in the plane in which the outermost edges of bottom portions of said peripheral flange lie and the center section extending in a plane which is inwardly offset relative to the plane of the end sections, corner connecting flaps hinged to opposite ends of the side wall forming panels and secured to outer face portions of the end sections of the body panels of the end frame members, and outer end wall forming panels hinged along the opposite ends of the bottom wall forming panel between said side wall forming panels and positioned against the outer faces of the body end sections of said end frame members so as to overlie said corner connecting flaps in covering relationship, and means securing said end wall forming panels in such relationship.
7. A tray-like container as recited in claim 6, and said blank being formed of paperboard and said end frame members being formed of molded plastic.
8. A tray-like container as recited in claim 6, and the end sections of the body panels of said end frame members having recesses within which said corner connecting flaps are seated.
9. A tray-like container as recited in claim 6, and the body panel of each said end frame members having pocket-forming shallow recesses at the ends thereof of a size and shape corresponding approximately to the size and shape of the corner connecting flaps and said corner connecting flaps being adhesively secured in said recesses.
10. A tray-like container as recited in claim 7, and the top portion of the peripheral flange of each said end frame member extending in overlapping relation to the topmost edge of the associated outer end wall forming panel.
11. A tray-like container as recited in claim 6, and each said end frame member having a protuberance projecting above the top portion of said peripheral flange and recesses in the bottom portion of said peripheral flange for receiving the protuberances in the end members of a like container when disposed in stack-forming relation beneath the same.
and creased to provide a series of integrally connected panels which form, when the container is set up, a bottom wall, double ply side walls connected to the side edges of the bottom wall by upwardly inclined wall sections,
and end walls extending between opposite ends of the side walls, said end Walls each including a substantially rigid plastic frame member having a body forming panel enclosed within a peripheral flange, said body forming panel being divided into sections with the sections extending in part approximately in the plane of the outermost edges of bottom portions of said peripheral flange and in part in a plane which is inwardly ofitset relative thereto, corner connecting flaps extending from opposite ends of the side walls and said body forming panel having recesses in which said corner connecting flaps are secured, and outer end wall forming panels hinged along the opposite ends of the bottom wall and secured against the outer faces of said end frame members and in overlying relation to said corner connecting flaps and being substantially co-extensive with the outer faces of said end frame members.
8 14. A tray-like container as recited in claim 13, and said peripheral flange on each said end frame member being of substantial width and having a portion extending along the top thereof which projects outwardly of said body forming panel and overlies the top edge of the associated outer end Wall forming panel.
References Cited UNITED STATES PATENTS 1,933,869 11/1933 Mosesian 21740 2,621,847 12/1952 Stefanich 21742 2,789,748 4/1957 Barbour 229-23 3,106,332 10/1963 Dieguez.
3,181,721 5/1965 Starkey et al. 2l742 DAVIS T. MOORHEAD, Primary Examiner.