This invention concerns stacking and nesting containers, more particularly thin walled, unitary boxes which not only nest and stack but also do not tilt one into the other when in superposed stacking relationship.
In recent years plastic or metal containers have largely displaced wooden containers or "tote boxes" for many reasons including the flammability, bulk and weight of wooden containers. The wooden box has also presented difficulties in nesting designs because such boxes must be excessively tapered on the sides in order to maintain the thickness required for strength. Excessive tapering, while permitting nesting to the smallest possible storage space, reduces the cavity size of the containers and therefore their shipping capacity.
For these and other reasons the container industry has substituted compression- or injection-molded plastic, heat-formed plastic, or welded and/or formed sheet metal, one piece, generally rectangular containers which do not require the excessive tapering for nesting but provide sufficient strength and capacity to compete successfully with wooden containers. These plastic or metal boxes have been provided in a great variety of designs, generally permitting nesting when in a first relative position, "cross stacking" when turned 90° in a second relative position (oblong shapes), or superposed tacking after one container has been turned 90° (square shapes) or 180° (oblong shapes) relative to another. By "superposed" is meant that stacking relationship in which the bottom of one container fits on or within the top of another container with each container oriented in the same direction. With respect to oblong containers, the superposed position would be 90° from the "cross stacking" position and all containers would be oriented longitudinally.
The known designs, however, whether square or oblong, have the fault of tilting or tending to fall one into the other when the containers are placed in superposed stacking relationship. When many of such containers are so stacked, particularly when filled with goods in transport, there is serious danger of damage to the merchandise being transported within the container, and actual damage often does result, due to tilting of one container into the other.
Accordingly, an object of this invention is to provide thin walled, stacking and nesting containers having structural characteristics which prevent the containers from shifting, tilting or falling one into the other when the containers are in superposed stacking relationship. These and other objects, features and advantages will be detailed in the description which follows.
In summary, the nontilt feature of the containers of this invention results from providing: (a) different numbers of vertically positioned ribs in at least one pair of opposing sidewalls; or (b) the same numbers of a plurality of vertically positioned ribs in at least one pair of opposing walls, said ribs being of unequal width and having unequal space between them but the ribs on opposite walls forming mirror images; or, (c) combining the foregoing arrangements (a) and (b) in the same container. This third arrangement is the preferred embodiment, and more particularly preferred is the same embodiment in which the ribs of those opposing walls having the same number of ribs are of unequal width and have unequal spacing therebetween, although the ribs on such opposing walls form mirror images. The nonuniformity of the foregoing structures necessarily causes misalignment or overlapping of the bottom of the ribs of one container relative to the top of the ribs of a second container when said containers are in superposed stacking relationship, thus preventing tilting of one container into another stacked in superposition immediately below the first container.
The invention is more particularly described in conjunction with the attached drawings, in which:
FIGS. 1, 2 and 3 are schematic top plan views illustrating the three primary geometrical configurations of containers of the invention;
FIGS. 4, 5 and 6 are also schematic top plan views showing the rib relationship of two containers each of FIGS. 1, 2 and 3 in superposed stacking position;
FIG. 7 is a perspective view of a preferred embodiment of a container of the invention;
FIG. 8 is a top perspective view of the container of FIG. 7; and
FIGS. 9 and 10 are elevational side and end views, respectively, of containers generally of the configuration of FIG. 7, in nesting relationship;
FIGS. 11 and 12 are elevational side and end views, respectively, of containers generally of the configuration of FIG. 7, in superposed stacking relationship.
With reference to FIGS. 1-3, FIG. 1 shows a container 100 of the invention, generally of rectangular, here oblong, configuration, having sidewalls 101, 102, 103 and 104. Vertically and inwardly extending within these sidewalls are ribs, corrugations, convolutions or similar projections 105, 106, 107, 108 and 109. These ribs generally are tapered from top to bottom of the container and on the same wall may have equal or unequal widths and may be spaced equally or unequally. Similarly, FIG. 2 shows container 200 generally of rectangular, here oblong, configuration and comprising sidewalls 203, 204, 205 and 206. Also extending inwardly and vertically of said walls are ribs 205, 206, 207 and 208. As compared with the container of FIG. 1, however, opposing walls 201 and 202 are provided with the same number of ribs, but these ribs are of unequal dimensions and have unequal spacing between them. However, the ribs on wall 201 are mirror images of the ribs on wall 202. In FIG. 3, the basic rib configurations of FIGS. 1 and 2 are combined. FIG. 3 shows a container 300 of generally rectangular, oblong, configuration, comprising sidewalls 301, 302, 303 and 304. Extending inwardly and vertically of said walls are an unequal number of ribs in walls 303, 304, that is, ribs 309, 310, 311 and 312 on wall 304, and ribs 313 and 314 on wall 303. Opposing walls 301 and 302 are provided with the same number of ribs but these ribs (305 and 306 on wall 301, 307 and 308 on wall 302) are of unequal width and have unequal spacing between them.
FIGS. 4, 5 and 6 illustrate misalignment or overlapping of the ribs of two structures each of FIGS. 1, 2 and 3, when said structures are placed in superposed stacking relationship, that is, when one structure is turned 180° and placed over an identical structure. It will be seen in FIG. 4 that when so stacked, the ribs of lower container 100.1 are misaligned with the ribs of upper container 100.2 such that container 100.2 will not tilt or fall into container 100.1. Similarly, in FIG. 5, the ribs of containers 200.1 and 200.2 are misaligned, preventing tilting of upper container 200.2 into lower container 200.1. In the preferred embodiment of the invention, represented by the stacking of the two containers 300.1 and 300.2 in FIG. 6, the same nontilt feature is evident, that is, the ribs of upper container 300.2 are misaligned with the ribs of lower container 300.1 such that the former will not tilt or fall into the latter.
In another preferred embodiment of the invention, as represented by FIG. 7, a container 700 of generally oblong, rectangular, configuration, having bottom wall 701 and side walls 702, 703, 704 and 705, is provided on wall 702 with ribs 706 and 707, on wall 703 with ribs 708, 709 and 710, on wall 704 with ribs 712 and 713, and on wall 705 with ribs 714 and 715. All of said ribs extend inwardly and upwardly, from top to bottom of the container, and are tapered from top to bottom. It will be noted that all of said ribs are of unequal width and the space between all of said ribs is unequal. It will also be evident that walls 702 and 703 have unequal numbers of ribs whereas walls 704 and 705 are mirror images of one another.
Also in FIG. 7, rib 710 extends interiorly as well as exteriorly around corner 711. The same is true of rib 708, although not illustrated. Container 700 also is provided with partially shown rib 721 which projects upwardly from bottom wall 701 and cooperates with projecting edge or lug 717 as resting ledges to prevent jamming of containers in nesting position. Rib 721 to achieve this purpose may be positioned lengthwise, crosswise, or may be X- or Y-shaped as desired.
FIG. 7 also displays, in part, indentations, on the upper edges of the sidewall ribs, which form saddles or shelves, as shelf 720 on rib 715. These shelves form resting ledges for the bottom walls of identical containers when in superposed stacking position thereon, thereby assisting the stability of the containers when so stacked.
FIG. 8 is a top view of FIG. 7 and illustrates some features of the invention with greater particularity. These features are the aforementioned shelves, such as shelf 720 on rib 715, rib 721 projecting upwardly from bottom wall 701, and inwardly projecting lugs or edges 717, 718 and 719 which provide resting ledges to prevent jamming of containers of the invention when in nesting relationship.
FIGS. 9 and 10 illustrate partial nesting positions of containers 700.1 and 700.2 similar to those of FIGS. 7 and 8. In each of FIGS. 9 and 10 it will be noted that corresponding ribs, such as side wall ribs 712.1, 712.2, 713.1 and 713.2, and end wall ribs 706.1, 706.2, 707.1 and 707.2, and shelves 720.1 and 720.2, likewise fit one into the other so as to facilitate stable nesting of the containers. The ultimate nesting positions are governed by the position of projections 717, 718 and 719 of FIG. 8 (not shown in FIGS. 9-12) and horizontally extending flanges 716 (FIGS. 7 and 8), 716.1 and 716.2 (FIGS. 9-12).
FIG. 10 provides an end view of the same containers as in FIG. 9, again showing the nesting relationship of corresponding ribs 706.1, 706.2, 707.1 and 707.2, and corresponding flanges 716.1 and 716.2. The same relationship regarding ultimate nesting positions are observable here.
When containers of the invention are turned 90° or 180°, the latter as illustrated with reference to containers 700.1 and 700.2 of FIGS. 11 and 12, the containers stack neatly one over the other by virtue of the misalignment of ribs on opposing sides of the containers. This is evident in FIGS. 11 and 12, whether the view be longitudinal as in FIG. 11, or whether it be an end view, as in FIG. 12. With reference to FIGS. 11 and 12, it will be noted that at least ribs 713.1 and 715.2 are misaligned. Similarly, in FIG. 12, ribs 706.1 and 707.1 are misaligned with ribs 708.2, 709.2, 710.2 and 711.2. In conjunction with said misalignment, there is also misalignment of shelves 720.1 and 720.2, thus enabling top container 700.1 to rest securely and stably within the rim and flange 716.2 of container 700.2.
It thus becomes evident that, in consequence of the misalignment of ribs of opposing walls when containers of the invention are in superposed stacking position as in FIGS. 4-6, 11 and 12, a top container will not tilt or fall into a lower container. Moreover, bottom walls 701.1 and 702.2 remain separated and will not jam, partly by virtue of flanges 716.1 and 716.2, but also as a consequence of bottom rib 721 and resting edges 717, 718 and 719 (not shown).
The principles of the invention are applicable to any generally rectangular container configuration whether such be square or oblong. Likewise, the containers of the invention need not be manufactured from a single molded piece, but may be bolted or welded together and the material may be plastic, metal, or any desirable combinations of such materials. Furthermore, the extent of taper and thickness of the walls and ribs is not critical and will depend upon the material of construction.
While the invention has been illustrated and described in what are considered to be the most practical and preferred embodiments, it will be recognized that many variations are possible and come within the scope thereof, the appended claims therefore being entitled to a full range of equivalents.