US 4,457,432 AGrant
Interlocking Stackable Tray
Issue Date:1984-07-03
•8 Claims
•1 Drawing Sheets
Abstract
An interlocking stackable tray having an opposed pair of sidewalls which are especially configured to be inwardly deflected toward each other into interlocked supporting engagement with a similar tray upon stacked placement of the similar tray thereon.
Metadata
Inventor
- Allan D. Solheim
Application Information
Application Number:US 5541956
Filing Date:1983-11-22
Priority Date:1982-04-19
Art Unit:241
Classifications
IPC:
B65D 2102
Field of Search:
34206211220237;238503;505;509;510;511;512126;1284 E;345
Patent Drawings (1 sheets)
Description
Brief Description of the Drawings
FIG. 1 is a perspective view showing the interlocking stackable tray according to the present invention.
FIG. 2 is a fragmentary side elevational view showing the manner in which the sidewalls of a tray shown in FIG. 1 will deflect to achieve a locking action.
FIG. 3 is a fragmentary side elevational view showing the manner in which the trays according to the present invention, and as illustrated in FIGS. 1 and 2, interlockingly stack on one another, and can be supported by the bottom of a lower tray on a suitable rack structure, and the like.
FIG. 4 is a fragmentary side elevational view showing the manner in which a tray according to the present invention can be suspended from a suitable rack structure.
FIG. 5 is a fragmentary, elevational view showing one tray according to the present invention being used as a cover for another like tray.
Description of the Preferred Embodiment
Referring more particularly to the drawings, FIG. 1 shows an interlocking stackable tray 10 in accordance with the present invention as comprising a substantially planar bottom wall 12 of generally rectangular configuration in plan and bordered by perpendicularly disposed pairs of spaced edges 14 and 16. An especially configured pair of substantially parallel, coextensive sidewalls 18 extend from opposed edges 14 of the bottom wall 12 and form a latch arrangement 20 which is designed to grippingly engage a bottom wall of a like tray which is stacked on the sidewalls 18 of the tray 10 in a manner to hereinafter be fully described.
Extending from the opposed pair of edged 16 of the bottom wall 12 and arranged substantially perpendicular to sidewalls 18, are a pair of end walls 22 codirectional with sidewalls 18 a distance substantially less than a distance the sidewalls 18 extend from the bottom wall 12 for permitting visual, and even physical, access into the tray 10 when other trays are stacked thereon. Each of the end walls 22 terminates laterally in an end surface 24 which is slanted from the associated bottom wall 12 so as to converge toward one another and cooperate with a like slanted pair of end surfaces 26 of the sidewalls 18 to form open corners 28. When constructed from a sheet of aluminum, steel, or other suitable metal, it will be appreciated that the tray 10 can be constructed merely by bending upwardly the walls 18 and 22 by techniques well known in the particular art. Further, it is to be understood that the tray 10 can be molded from a suitable synthetic resin, and the like, if so desired. It will also be appreciated that end walls 22 can be reduced in height as desired, and even eliminated if so desired and the intended use of the tray 10 permits, without eliminating the interlocking capability of the latch arrangement 20.
Referring more particularly to FIG. 2 of the drawings, the bottom wall 12 defines an upper surface 30 and a lower surface 32, with each of the sidewalls 18 including a planar section 34 arranged to extend upwardly angularly and inwardly from their respective one of the opposed edges 14 of the bottom wall 12, with the planar section 34 defining an upper end or edge 36. Each of the sidewalls 18 further includes an integral ledge 38 which extends outwardly from the upper end 36 of the planar section 34, and is disposed so as to normally lie in a plane which slopes angularly and downwardly relative to the plane of the bottom wall 12, with a lip 40 being formed on the outwardly extending end of the ledge 38, so as to extend generally perpendicularly and upwardly therefrom. Planar sections 34, ledges 38, and lips 40 of the sidewalls 18, as well as the rest of the tray 10, are fabricated of a resiliently deflectable material, as mentioned above, so that when a force is exerted on the upper ends 36 of the planar sections 34, i.e., the junctions of the planar sections 34 and the ledges 38, in a downward direction which is substantially perpendicular to the bottom wall 12, the opposed sidewalls 18 will be deflected inwardly toward each other. FIG. 2 shows one of the sidewalls 18 in its normal, or undeflected position in solid lines and shows the inwardly deflected position thereof in broken lines.
FIG. 3 shows the manner in which the sidewalls 18 of one of the trays 10 will move into supporting interlocking engagement with a like tray 10 when the like tray is stackingly arranged thereon. When the like, or top tray 10 is downwardly lowered toward the tray upon which it is to be stackingly arranged, i.e., the bottom tray, the bottom wall 12 of the top tray will first come into engagement with the upper ends 36 of the planar sections 34 of the sidewalls of the bottom tray. Thus, the entire weight of the top tray will be concentratingly brought to bear on the relatively small surface areas at the upper ends 36 of the opposed sidewalls 18 of the bottom tray. In that the forces resulting from the weight of the top tray are concentrated in the relatively small areas at the upper ends 36 of the planar sections 34, the force per unit area, or pressure, at those upper ends 36 will be high and the sliding friction between the inwardly moving sidewalls of the bottom tray and the bottom wall of the top tray will be relatively low.
As a result of the above described factors, the sidewalls 18 of the bottom tray 10 will be easily moved inwardly toward each other which moves the ledges 38 of the sidewalls into contiguous supporting engagement with the bottom wall of the top tray 10, and will simultaneously move the lips 40 thereof into gripping engagement with the opposed edges 14 of the bottom wall at the junction of the sidewalls of the top tray.
While the angle between the planar sections 34 and associated ledges 38 of the sidewalls 18 are not considered critical, an angle of 68.degree. has been found satisfactory when used in conjunction with an angle of 15.degree. relative to the normal for the planar section 34 relative to an associated bottom wall 12. These angles are indicated by a and b in FIG. 2.
A rack 42, as seen in FIG. 3, of conventional construction including uprights, such as that designated at 44 from which cooperating pairs of shelves 46 (one of which is illustrated in FIG.3) can extend cantilever-wise, can be used to support a lowermost of a stack of trays 10 according to the present invention. Although not illustrated, it will be appreciated that such a stack of trays could be supported on a table, floor, or other suitable surface.
Alternatively, trays 10 can be supported as illustrated in FIG. 4 by resting the lower surfaces of the ledges 38 of a tray 10 on shelves 46 of the rack 42. As shown by broken lines in FIG. 4, a further tray 10 can be stacked atop the supported tray 10 due to the inward deflection of the sidewalls 18 caused by the upwardly directed force applied at the extending edges of the ledges 38 from the shelves 46 and the downwardly directed force of the upper tray 10. Thus, the upper tray 10 will be grippingly engaged by the lips 40 of the sidewalls 18 of the supported tray 10 in the manner hereinbefore fully described.
Further, the same action which causes the suspended tray 10, as illustrated in FIG. 4, to grippingly engage a like tray 10 stacked thereon will cause a stack of trays to remain interlocked even when manually manipulated by picking the trays up by the ledges 38 of the lowermost tray 10 in the stack in a manner not illustrated.
FIG. 5 shows the manner in which the tray 10 can be inverted into a like tray 10 to form a cover for it. This feature particularly is advantageous for conserving space during storage of the trays 10, as it permits nesting of a pair of the trays. As seen, a bottom 12 of an upper tray 10 will rest upon the lips 40 (one shown) of the lower tray 10.
As can be readily understood from the above description and from the drawings, an interlockable, stackable tray according to the present invention permits positive engagement between members of a stack of trays by the use of only a pair of sidewalls, thus permitting the other sidewall to be configured, and even eliminated, as circumstances permits in order to provide at least visual access of the contents of a tray disposed in a stack of such trays. Further, the manner in which the lowermost tray is supported and/or manipulated will not affect the interlocked relationship between the stacked trays.
While the principles of the invention have now been made clear in the illustrated embodiment, there will be immediately obvious to those skilled in the art, many modifications of structure, arrangements, proportions, the elements, materials and components used in the practice of the invention, and otherwise, which are particularly adapted for specific environments and operation requirements, without departing from those principles. The appended claims are therefore intended to cover and embrace any such modifications within the limits only of the true spirit and scope of the invention.
Claims
What I claim is:
1. An interlocking stackable tray comprising: (a) a bottom wall of planar configuration and having an opposed pair of substantially parallel side edges; and (b) a pair of sidewalls extending integrally and generally upwardly from different ones of the pair of side edges of said bottom wall, said pair of sidewalls being inwardly deflectable toward each other into interlocking supporting engagement with a like tray upon stacked placement of the like tray thereon, each sidewall of said pair of sidewalls including, I. a planar section extending angularly upwardly and inwardly from its respective one of the pair of side edges of said bottom wall and defining an upper end, II. a ledge extending outwardly from the upper end of said planar section and normally lying in a plane which slopes angularly and downwardly relative to the plane of said bottom wall so that when the like tray is stackingly placed on said sidewall, the force resulting from the weight of the like tray will be concentratingly exerted on the upper end of said planar section to inwardly deflect said sidewall which moves said ledge into supporting contiguous engagement with the bottom wall of the like tray adjacent one of its pair of side edges, said ledge having an outer end, III. a lip extending generally upwardly from the outer end of said ledge for movement with said sidewall into gripping engagement with the one of the pair of side edges of the bottom wall of the like tray upon stacked placement of the like tray on said sidewall.
2. An interlocking stackable tray as claimed in claim 1 wherein each of said pair of sidewalls is free standing.
3. An interlocking stackable tray as claimed in claim 1 wherein each of said pair of sidewalls is free standing and extends substantially the full length of its respective one of the pair of side edges of said bottom wall.
4. An interlocking stackable tray as claimed in claim 1 wherein said tray is formed of resiliently deflectable material.
5. An interlocking stackable tray as claimed in claim 1 and further comprising: (a) said bottom wall having an opposed pair of substantially parallel end edges which are substantially perpendicular with respect to the pair of side edges thereof; and (b) a free standing end wall extending upwardly from one of the pair of end edges of said bottom wall.
6. An interlocking stackable tray as claimed in claim 5 wherein said end wall extends upwardly from said bottom wall a distance which is less than the distance that said pair of sidewalls extend upwardly therefrom.
7. An interlocking stackable tray as claimed in claim 1 and further comprising: (a) said bottom wall having an opposed pair of substantially parallel end edges which are substantially perpendicular to the pair of side edges thereof; and (b) a pair of free standing end walls each extending upwardly from a different one of the pair of end edges of said bottom wall.
8. An interlocking stackable tray as claimed in claim 7 wherein each of said pair of end walls extends upwardly from said bottom wall a distance which is less than the distance that said pair of sidewalls extend upwardly from said bottom wall.