Cross-stacking bottle case

1 3~55~3 CROSS-STACKING BOTTLE CASE TECHNICAL FIELD The present invention relates to low depth stackable bottle cases for use in retaining and transporting bottles.

More particularly, 5 the present invention relates to beverage bottle cases that comhinP low depth with high stability for stored bottles.

BACKGROUND OF THE INVENTION Plastic bottles are widely used as containers for retailing soft drinks and other beverages.

One type of plastic, polyethylene 10 terephthalate (PET), has become particularly popular because of its transparency, light weight, and low cost.

In addition to being fle~ihle, the walls of PET bottles are strong in tension and thus can safely contain the pressure of a carbonated beverage.

Moreover, conventional PET bottles can bear surprisingly high compressive loads, provided 15 that the load is directed substantially along an axially symmetric axis of the bottle. A single PET bottle can support the weight of many bottles of the same size filled with beverage if the bottle is standing upright on a flat, horizontal surface and the weight of the other bottles is applied to the closure of the single bottle and is directed sub2 0 stantially vertically along the symmetric axis.

However, if acompressive load is applied to a conventional PET beverage bottle along a direction other than the symmetry axis of the bottle, the bottle tends to buckle.

This tendency of conventional PET bottles to give way under off-axis compressive loads is particularly pronounced for 25 large capacity bottles, such as the two-liter bottle widely used for marketing sof t drinks.

Soft drink bottles are ordinarily packaged by bottlers in cases or other containers, several bottles to the case. for shipment to retailers or for storage.

Cases of bottles are customarily stacked on top of each other.

In warehouses, cases of bottles are frequently -2- l 335583 stacked on pallets which can be lifted and moved about by fork-lift trucks.

The stacks of cases on the pallets must therefore be particularly stable in order to remain standing in the face of the jostling inherent in being moved about. A technique for interconnecting col5 umns of cases, called ~cross stacking," is often used to improve thestability of cases of bottles loaded on a warehouse pallet.

Cross stacking generally involves stacking rectangular bottle cases to build up a layered structure, with each layer having cases oriented parallel to each other and with the cases in adjacent layers being oriented at 10 right angles to each other.

Since each case in the cross-stacked layer rests on at least two cases in the layer below, the cases of the crossstacked layer tend to keep the cases on which they rest from moving apart from each other.

The cross-stacked layer therefore st~hili7P-s the structure.

Because of the tendency of conventional P~T beverage bottles to buckle under off-axis loads, attempts to stack cases of these bottles give rise to serious problems.

Bottles can tilt away from vertical alignment upon stacking if conventional partitioned cases having low side walls are used to contain the bottles.

Tilted bottles in the lower 20 cases of a stack can buckle and give way, causing the stack to fall.

Even absent buckling, the tendency of bottles to tilt in conventional low-sided cases causes problem.c.

Tilting generally places an undesirably low limit on the nl]mber of tiers in a stack since the tilting of bottles in one case can cause the next higher case in the stack to tilt.

2 5 This leads to instability if too many tiers are included in the stack.

Previously, these problems were dealt with by packaging beverage bottles in corrugated-paper cartons having high sides, often equal in height to the height of the bottles.

Two-liter PET bottles filled with soft drinks were o~ten packaged in enclosed corrugated paper 30 cartons for storage and shipment.

Although the high sides of these paper cartons reduce the incidence of tilting and provide additional support when the cartons are stacked, the cartons are expensive.

The cost of the cartons cannot ordinarily be distributed over a nllmher of repeated uses since corrugated-paper cartons generally are not rugged 3 l 335~83 enough for reuse and therefore they are usually discarded by the retailer.

One solution to the problems of full depth corrugated-paper cartons is plastic full depth cases.

In plastic full depth cases, the 5 sides are load bearing.

Full depth plastic cases also have numerous disadvantages.

They are ~pencive to manufacture.

They are also e~rpencive to ship and to store empty in a user~s warehouse as they require lots of space.

Also, they totally surround the bottles, thereby preventing display of the bottles.

To overcome these problems plastic low depth cases have been used. A low depth case is one in which the side walls are lower than the height of the stored bottles, and in which the bottles support the weight of additional cases stacked on top.

Some examples of low depth cases follow.

However, these too have drawbacks.

Some cases, such as the cases disclosed in the deLarosiere, require additional structure to hold the bottles and insure complete bottle stability, even though the case depth is more than 25% of the height of the bottles.

Various plastic reusable bottle carriers are known in the art.

One reusable bottle carrier is disclosed in U.S.

Patent No. 3,055,542 to Russo.

The bottle carrier can be made of a plastic, and is assembled from two pieces: a handle and a carrier body having six cups for softdrink bottles.

In order to stack the bottle carriers when empty, the h~n~les must be removed.

This is very inconvenient and time consuming.

The '542 bottle carrier is also seriously limited regarding 2 5 stacking loaded carriers.

It cannot be stacked in a conventional cross-stacked structure because, as shown in figures 3 and 10, the spacing between the bottles in the carriers is different in the directions parallel and perpendicular to the handle of the carrier.

Kappel U.S. 2,970,715 is one of the earlier embodiments of molded plastic low depth bottle carrying cases.

Each bottle rests on a raised flat surface within an individual compartment.

The bottom of the case is formed with recesses for receiving bottle tops when loaded cases are vertically stacked.

However, Kappel does not indicate the size of the carrying case relative the bottles being carried.

~ 335~ In Bunnell, U.S. 3,812,996, a re~c~hle plastic bottle carrying case for beer bottles is dic~ ed The case is designed with a plurality of bottle compartments having flat bottom walls.

The cases are designed to be cross-stacked; the cases are dimensioned so that the center-to-center distance between adjacent bottles within a case is the same as the center-to-center distance between adjacent bottles in adjacent cases in abutting relationship.

The bottles are co-linear.

Although a plurality of loaded carrying cases is designed to be vertically stackable with the weight of upper cases supported by the bottles within lower cases, the outer surface of the bottom wall of the case is flat.

Garcia, U.S. 3,24~,996 discloses a low depth plastic bottle container for milk bottles.

The container is shorter than the bottles which extend above the top surface of the container walls.

In Garcia, the bottles, rather than the walls of the container, are load bearing.

Indented circular portions may be formed in the bottom wall to receive bottle tops when containers are vertically stacked.

Like many prior art bottle carriers, the Garcia container is a low depth case that can be used with a variety of bottles.

However, the case is 2 o not a very low depth case and is more expensive than very low depth cases.

It also does not have the display capabilities of very low depth cases.

A more recent attempt to solve the problem of providing reusable, cross-stackable PET bottle cases is disclosed in U.S.

Patent No.

4,344,530 to deLarosiere.

The '530 patent has many of the features and problems of Garcia and licclns~s a plastic PET bottle case that is cross stackable and has a very low depth as shown in the figures.

This low depth is disclosed as being approximately 1/6 the height of the PET bottles, or approximately 2 inches.

However, in practice, this depth i_ insufficient and does not prevent bottles from tipping over.

This creates a large degree of lateral instability.

In practice these cases are 3-3~ inches high.

Additionally, the bottle retaining pockets are required to have a raised annular bottle seat ring which fits within the inner indentation formed in the base of many bottles to insure bottle stability.

Also, this does not permit petaloid bottles to .

_ 5 1 335583 rotate within the bottle pockets for display purposes.

Additionally, it does not permit bottles without a base indentation to be adequately retained. deLarosiere also incorporates a bottle spacing feature that co-linearly aligns bottles to facilitate cross stacking.

SnMMARY OF ~ln~ lNv~.llON It is an object of an aspect of the present invention to provide a durable plastic reusable bottle case having a very low depth that is stable when full cases or empty cases are stacked on top of each other.

It is an object of an aspect of the present invention to provide a stackable bottle case in which bottles do not tip when a plurality of loaded cases are stacked on top of each other, in which additional bottle base support structure is unnecessary, in which bottles without base indentations may be retained, and in which petaloid bottles may be rotated.

It is an object of an aspect of the present invention to provide a bottle case having the above features that uses less material, is lighter in weight, and is cheaper to manufacture.

These and other objects are attained by the stackable low depth case of the present invention. The case includes four side walls and a bottom portion. A plurality of upwardly projecting hollow columns are disposed in the bottom portion. These columns preferably do not extend from the top surface of the bottom portion. The columns, walls, and bottom portion define a plurality of bottle retaining pockets. The bottle retaining pockets have flat bottom surfaces to permit retention of bottles without base indentations and to permit rotation of bottles. The columns extend upwardly from the base portion a distance approximately one third of the height of the bottles to be retained.

The columns are hollow to permit empty cases to stack top to bottom. The lower surface of the bottom portion 1 3~558~ has circular concave portions with central retaining openings to facilitate stacking of filled cases top to bottom. When a case is disposed on a loaded lower case, the bottle tops of the bottles in the lower case are guided toward the central retaining openings by the circular concave portions.

The case of this invention has a very low depth with upwardly exten~;ng columns. This provides numerous advantages. This case may be formed without special bottle base supports because the columns give the case a higher effective height. This also enhances bottle visibility and reduces manufacturing costs.

The case may be used for any size bottles such as 2-liter and 3-liter bottles. The case may be shaped to receive 6, 8, or any other number of bottles as well as 6-packs and 8-packs.

Additionally the effective height of the case, the total column height, need not be limited to 1/3 the height of the bottles.

Various aspects of the invention are as follows:

A cross-stacking case for retaining and transporting bottles comprising: outer side walls forming an outer shell; a case bottom attached to said side wall; a plurality of means for supporting outer surfaces of bottles, generally disposed within planes defined by said outer shell and each supporting means having at least one bottle supporting surface, said bottle supporting surfaces defining, in combination with said outer shell and said case bottom, a plurality of bottle retaining pockets with at least one bottle supporting means associated with each pocket; and receiving means, generally disposed within said outer shell, extending above the height of a top surface of a first of said side walls and having a recess for receiving a side wall of an upper identical case when said lower cross-stacking case is empty.

1 335583 6a A cross-stacking case for retaining and transporting bottles comprising: outer side walls forming an outer shell; a case bottom attached to said side wall; a plurality of means for supporting outer surfaces of bottles, generally disposed within planes defined by said outer shell and each supporting means having at least one bottle supporting surface, said bottle supporting surfaces defining, in combination with the outer shell and the case bottom, a plurality of bottle retaining pockets with at least one bottle supporting means associated with each pocket; and a plurality of receiving means, generally disposed within said outer shell, exten~ing above the height of a top surface of a first of said side walls and each of said means having a recess, for receiving a side wall of an upper identical case when said lower crossstacking case is empty.

A cross-stacking case for retaining and transporting bottles comprising: four outer side walls forming a rectangular outer shell having a ratio of the length to the width of the outer shell being substantially equal to the number of bottles said case holds in the lengthwise direction to the number of bottles said case holds in the widthwise direction; a case bottom attached to said side wall; and a plurality of means for supporting outer surfaces of bottles, generally disposed within planes defined by said outer shell and each supporting means having at least one bottle supporting surface, said bottle supporting surfaces defining, in combination with the outer shell and the case bottom, a plurality of bottle retaining pockets, with at least one bottle supporting means associated with each pocket; wherein a first of said plurality of bottle supporting means is disposed above the height of a top surface of a first of said side walls and 1 335583 6b has a recess for receiving a side wall of an upper identical case when said lower cross-stacking case is empty.

A cross-stacking low depth case for retA;ning and 5 transporting bottles comprising: four outer side walls forming a rectangular outer shell having the ratio of the length to the width of said outer shell being substantially equal to the number of bottles said case holds in the lengthwise direction to the number of bottles said case holds in the widthwise direction and having a center line of the length of the case extending through the center of the longer pair of side walls of the case; a case bottom attached to said side wall; and a plurality of supporting means for supporting outer surfaces of bottles, generally disposed within planes defined by said outer shell and each supporting means having at least one bottle supporting surface, said bottle supporting surfaces defining, in combination with said outer shell and said case bottom, bottle retaining pockets, with at least one bottle supporting means associated with each pocket; and wherein a first of said plurality of bottle supporting means is disposed about the center line of the length of the case and includes a portion extending above the height of a top surface of a first of said side walls, said 2s portion above the height of said first side walls includes a recess which extends along the center line of the length of the case.

A low depth case comprising: outer side walls forming an outer shell wherein top edges of said side walls define a top surface of the outer shell; a case bottom attached to said side wall; a plurality of means for supporting outer surfaces of bottles, generally disposed within planes defined by said outer shell and each supporting means 1 335583 6c having at least one bottle supporting surface, said bottle supporting surfaces defining, in combination with said outer shell and said case bottom, a plurality of bottle ret~i n ing pockets with at least one bottle supporting means associated with each pocket; and receiving means, disposed within said outer shell, about a center line of the length of the case and above the height of the top surface of the outer shell of the case, which, when said case is empty, is for receiving a side wall of an upper identical case.

A low depth case comprising: outer side walls forming an outer shell wherein top edges of said side walls define a top surface of the outer shell; a case bottom attached to said side walls; a plurality of means for supporting outer surfaces of bottles, generally disposed within planes defined by said outer shell and each supporting mean having at least one bottle supporting surface, said bottle supporting surfaces defining, in combination with the outer shell and the case bottom, a plurality of bottle retaining pockets with at least one bottle supporting means associated with each pocket; and projections extending above said bottle supporting means and above the top surface of said outer shell, said projections positioned to define slots which interlock with a side wall of an identical upper case for cross-stacking the identical upper case onto the lower low depth case when the lower low depth case is empty of bottles.

A low depth case for retaining and transporting 2-liter PET bottles comprising: four outer side walls forming a rectangular outer shell wherein top edges of said side walls define a top surface of the outer shell and having a ratio of the length to the width of the outer shell which is substantially equal to the ratio of the number of bottles said case holds in the lengthwise direction to the - 1 335583 -6dnumber of bottles said case holds in the widthwise direction so that a plurality of said cases may be cross-stacked, wherein at least some of said cases in one layer can be disposed at 90 angles from cases in adjacent layers, in which condition the center-to-center distance between adjacent bottle retaining pockets within said case and between two adjacent cases having abutting side walls are substantially equal; a case bottom attached to said side wall and including: an upper surface; and a lower surface having means for resting the case bottom on closures of 2-liter PET bottles in a subjacent case and for aligning each closure with said case bottom for stacking said case; and a plurality of means for supporting outer surfaces of bottles, generally disposed within planes defined by said outer shell and each supporting means having at least one bottle supporting surface, said bottle supporting surfaces defining, in combination with the outer shell and said case bottom upper surface, a plurality of bottle retaining pockets, with at least one bottle supporting means associated with each pocket and each of said bottle supporting means including: a horizontal platform disposed substantially coplanar with the height of the top surface of said outer shell; and a plurality of upwardly disposed projections extending from said platform of said bottle supporting means and below a top surface of the 2-liter PET bottles to be retained, said projections defining a slot and said slot is aligned to cooperate with a side wall of an upper identical case when said upper identical case is disposed at 90 to the lower low depth case and said lower low depth case is empty.

A cross-stacking low depth case for retaining the transporting as many as eight 2-liter PET bottles at a time comprising: four outer side walls forming a rectangular 1 335583 6e outer shell wherein top edges of said side walls define a top surface of the outer shell, the length of said outer shell is twice as long as the width of said outer shell and a center line of the length of the case extends through the center of the longer pair of said walls of the case;

a case bottom attached to said side wall and including: an upper surface; and a lower surface having means for resting the case bottom on closures of 2-liter PET bottles in a subjacent case and for aligning each closure with said case lo bottom for stacking said case; and a plurality of means for supporting outer surfaces of 2-liter PET bottles, generally disposed within planes defined by said outer shell and each supporting means having at least one bottle supporting surface, said bottle supporting surfaces defining, in combination with said outer shell and said case bottom upper surface, eight 2-liter PET bottle retaining pockets, with at least one bottle supporting means associated with each pocket; wherein a first of said plurality of bottle supporting means is disposed about the center line of the length of the case and includes: a horizontal platform substantially coplanar with the height of the top surface of said outer shell; and a projection exten~;ng above and from said horizontal platform, said projection including a slot which extends along the center line of the length of the case, said slot receiving a side wall of an identical upper case when said lower low depth case is empty; and wherein the height of said case from said lower surface of said case bottom to a top of said projections is no higher than one-half the height of the stored 2-liter PET bottles to be retained.

1 335583 6f Various additional advantages and features of novelty which characterize the invention are further pointed out in the claims that follow. However, for a better underst~n~ing of the invention and its advantages reference should be made to the accompanying drawings and descriptive matter which illustrate and describe preferred embodiments of the invention.

n~ lY~-oN 0~ TRR DRAWT~GS Figure 1 is a perspective view of a stackable low depth case according to the present invention.

Figure 2 is a side view, partially in section taken along line 2-2 of Figure 4, of the case of Figure 1.

Figure 3 is an end view, partially in section taken along line 3-3 of Figure 4, of the case of Figure 1.

Figure 4 is a top view of the case of Figure 1.

Figure 5 is a bottom view of the case of Figure 1.

Figure 6 is a sectional view taken along line 6-6 of Figure 4.

Figure 7 is a sectional view taken along line 7-7 of Figure 4.

Figure 8 is a sectional view taken along lines 8-8 of Figure 4.

Figure 9 shows partial sectional views illustrating an upper case stacked on top of a lower case with the lower case filled with bottles. Figure 9a is taken along line 9a-9a of Figure 4, and Figure 9b is taken along line 9b-9b of Figure 4.

Figure 10 is a sectional view similar to that of Figure 6, which is taken along line 6-6 of Figure 4, showing two empty stacked cases.

1 335583 Figure 11 is a sectional view similar to that of Figure 2, which is taken along line 2-2 of Figure 4, showing a side view of two empty stacked cases.

Figure 12 is a perspective view of a stackable low depth case according to another embodiment of the present invention.

Figure 13 is a side view of the case of Figure 12.

Figure 14 is an end view of the case of Figure 12 having a different handle portion.

Figure 15 is a top view of the case of Figure 12.

Figure 16 is a bottom view of the case of Figure 12.

DETATT~n DESCRIPTION OF THE ~:KK~ EMBOD~ Nl~ As shown in Figure l, the stackable low depth bottle case 10 has four side walls 12, 14, 16, 18. The top surfaces of these four side walls are identified as 12', 14', 16' and 18'. Side walls 12, 16 are relatively long and side walls 14, 18 (end walls) are relatively short. Case 10 is rectangular and is therefore symmetric about both center lines 17 and 19 which bisect the bottom surface. Center line 17 of the length of the case extends through the center of the longer pair of side walls 12 and 16 of the case. Center line 19 of the case extends through the center of the shorter pair of side (i.e., end) walls 14 and 18 of the case. The depth or height of side walls 12, 14, 16, 18 is relatively low compared to the height of the bottles retained therein.

Preferably, case 10 is rectangular and symmetric around both central axes.

The ratio of the length of long side walls 12, 16 to the length of short side walls 14, 18 is substantially equal to the ratio of the number of bottles the case holds in the lengthwise direction to the number of bottles the case holds in the widthwise direction.

For example, an 8-bottle case is twice as 1 335583 7a long as it is wide and holds bottles in a 4 x 2 relationship.

As best shown in Figures 4 and 5, case 10 also includes a bottom portion 20 attached to side walls 12, 14, 16, 18 to form the outer shell of case 20.

Preferably, case 10 is made from plastic and is molded integrally as a single component.

Bottom portion 20 has an upper surface 22 and a lower surface 24.

Upper surface 22 is substantially flat.

Lower surface 24 is formed as a plurality of circular concave portions 26 each having a central retaining opening 28 disposed therein. The number of circular concave portions corresponds to the number of bottles the case is designed to retain. The function of circular concave portions 26 and central retaining openings 28 will be described in detail below.

-8- 1 335583 Case 10 is formed having a plurality of vertical walls 29 and upwardly projecting hollow col~mn-c 30 ~icp~sed within side walls 12, 14, 16, 18.

In the embo~imPnt of Figures 1-11 col~mr~c 30 do not extend to and do not contact the top surface of bottom portion 20.

5 Vertical walLc 29 do extend to the top surface of bottom portion 20.

The side edgec of vertical walls 29 abut coll)mnc 30 and help tO secure coll~mn-c 30 to bottom portion 20.

Vertical wal~c 29 and columns 30, when comhin~l with upper surface 22 of bottom portion 20 and sidewalls 12, 14, 16, 18, define a plurality of bottle retaining pockets 32.

10 Column-c 30 are hollow to permit vertical stacking of empty cases 10.

Col~mn-c 30 extend above bott~m portion 20 a distance approximately one third of the height of the bottles to be retained in case 10.

This increases the effective height of the case while maintaining high bottle visibility and low manufacturing costs.

For example, where cases 10 are 5h~peld to retain 2-liter bottles, colllmnC 30 e~lend upwardly approximately four inches. colllmnc 30 are licp~ce~ either along the walls 12, 14, 16, 18 or away from the walls, centrally within bottom portion 20.

Coll~mnc 30 rlicp~ced in the corners belween two adjacent walL have one curved surface 34.

Colllmns 30 ~lisp~d on the side_ of 20 one of the walls have two curved surfaces 34 and one flat surface 36 dicpoced therebetween.

The two curved surfaces 34 help define two separate and adjacent bottle retaining pockets 32.

Flat surface 36 is ~icp~ed bel~een these two bottle ret~ining pockets.

Columns 30 that are ~licpr~ced centrally within bottle portion 20 are octagonally sh~l 25 These colllmr~c 30 have four alternating curved surfaces 34 and four alternating flat sur~aces 36.

The four curved surfaces 34 define portions of four bottle retaining pockets 32 and the four flat surfaces 36 separate these pockets.

Four curved surfaces 34 on four separate colllmr~c 30 form the four corners of a bottle retaining pocket 32.

30 Thus, colum~c 30 having two curved surfaces 34 form a corner of two adjacent bottle retaining pockets 32, and colllm~c 30 having four curved surfaces 34 form a corner of four adjacent bottle retaining - 8a 1 335583 pockets 32. As seen in Figures 1, 2, 4 and 11, the columns disposed about a centerline 17 of the length of the case include recesses 50 and 51 which extend downwardly to a height which substantially equals a side wall height. These recesses are for receiving a side wall of an identical upper case.

The upper surface 22 of bottom portion 20 within bottle retaining pockets 32 is substantially flat. This permits retention of bottles 9 1 3 3 5 5 8 3 regardless of the configuration of the bottom of the bottles.

Also, this allows petaloid bottles to be rotated within the bottle retaining pockets to facilitate display of the product.

The very low depth feature of case 10 further enhances product display.

The circular concave portions 26 of lower surface 24, shown clearly in Figure 2, allow cases 10 filled with bottles to be vertically stacked for transportation, storage, and display purposes.

Circular concave portions 26 are formed of ribs or projections which define the circular concave shape.

These ribs also form central retaining opening 28.

Central retaining opening 28 is sized to receive the bottle top ga of a bottle 9 which is ~isp~sed in a lower case 10 as shown in Figure 9.

Bottle top 9a fits adjacent central retaining opening 28 so that central retaining opening 28 retains bottle top 9a in pasition against lower surface 24.

The concave shape of circular concave portion 26 assists bottle top 9a to abut central retaining opening 28.

When an upper case 10 is being positioned on loaded lower case 10, often bottle tops 9a will not precisely line up with respective central retaining openings 28.

However, bottle tops 9a will contact circular concave portions 26 which, bec~ce of their concave shape, will guide bottle tops 9a into central retaining opening~ 28.

Additionally, the center-to-center distances between adjacent bottle retaining pockets within one case are substantially equal.

Similarly, the center-to-center distances between adjacent bottle retaining pockets in adjacent cases with abutting side walls is substantially equal.

2 5 A plurality of empty cases 10 may also be stably stacked on top of each other.

Because columns 30 are hollow, in one embodiment, at least a portion of column 30 in a lower case 10 may be disposed within a portion of a respective column 30 in an upper case 10.

This permits a stable male-female type interlocking.

This stacking arrangement can be performed with the embodiment of case 10 illustrated in Figures 12-16.

In the embodiment of Figures 1-11, a slightly different interlocking of empty stacked cases 10 occurs.

As best illustrated in Figures 2, 3, 6, ~, 8, and 11, columns 30 do not extend to bottom portion 3 5 20.

There is a gap between bottom portion 20 and the bottom of .. . . .

`- 1 335583 columns 30.

This configuration allows empty cases of the Figure 1 embodiment to stack vertically without having the lower portion of columns 30 taper outwardly to receive columns 30 of a lower case 10.

As shown in Figures 10 and 11, two empty cases 10 are stacked vertically.

The top portions of columns 30 of the lower case do not extend into columns 30 of the upper case.

Only projecting portion 3Oa of a lower column 30, shown in Figure 10, which is disposed only on some columns 30 as described below, enters an upper column 30. Lower columns 30 fit within ribs 21 located on bottom portion 20 of case 10 and corresponding to respective columns 30. The interlocking of columns 30 within ribs 21 securely and stably connects empty stacked cases 10.

Side walls 14, 18, are formed with handle portions 38 to facilitate carrying case 10. Preferably, handle portions 38 have finger recesses 40 to further aid carrying case 10. In one preferred embodiment, some columns 30 may have slightly different heights that the remaining columns 30. In Figure 1, the central columns 30 have projecting portions 3Oa which extend above the other columns 30. This causes cases 10 to wobble when placed upside down on a flat surface and prevents cases 10 from being used upside down merely as stacking boxes to stack other items. In Figure 2, one of projecting portions 3Oa is not shown to provide a better illustration for Figure 11.

Figures 12 - 16 illustrate an alternate embodiment of the stackable low depth case of the present invention. In this embodiment, the shape and construction of columns 30 differs from that of the first embodiment.

Also, vertical walls 29 are not used.

The remaining features of the case are otherwise the same.

In this embodiment, columns 30 are formed with horizontal platforms 31 located at a level substantially 1 335583 11 coplanar with the top surfaces 12', 14', 16' and 18' of side walls 12, 14, 16, 18. Projections 3la are disposed on platforms 31. Projections 31a include a substantially triangular or wedge-shaped support portion and have curved surfaces 34a extending from curved surfaces 34 of columns 30.

Curved surfaces 34a are narrower than curved surfaces 34 to decrease the weight and bulk of the case and curved surfaces 34a lie in the same curved plane as respective curved surfaces 34. The wedge-shaped portion of projections 31a are substantially perpendicular to curved surfaces 34a.

When empty cases of this embodiment are stacked top to bottom, projections 31a of a lower case may fit within the openings of respective columns 30 of an adjacent upper case if columns 30 extend to the top surface of bottom portion 20.

As seen in Figures 13 and 14, these projections 3la, which are above the side walls of the case, define recesses 151, 152, 153 and 154 for receiving side walls of an upper case. Recess 151 extends along the center line 17 of the length of the case and recess 154 extends along the center line 19 of the width of the case.

In addition, recesses 152 and 153 extend parallel to the center line 17 of the length of the case.

Further, these recesses 151, 152, 153 and 154 extend downwardly to a height which substantially equals the height of the side walls.

Numerous characteristics, advantages, and embodiments of the invention have been described in detail in the foregoing description with reference to the accompanying drawings. However, the disclosure is illustrative only and the invention is not limited to the precise illustrated embodiments. Various changes and modifications may be effected therein by one skilled in the art without departing from the scope or spirit of the invention.