US2901157A

US2901157A - Multicellular carriers

Info

Publication number: US2901157A
Application number: US673067A
Authority: US
Inventors: Marshall I Williamson
Original assignee: Federal Paper Board Co Inc
Current assignee: Federal Paper Board Co Inc
Priority date: 1957-07-19
Filing date: 1957-07-19
Publication date: 1959-08-25
Anticipated expiration: 1976-08-25

Description

MULTICELLULAR CARRIERS Aug. 25, 1959 lM. l. WILLIAMSON 'MULTICELLULAR CARRIERS 5 Sheets-Sheet 2 Filed July 19, 1957 [NV EN TOR. Mars/1a!! Williamson BY n #wi 5. HMM

ATTORNEY Aug. 25, 1959 M. l. WILLIAMSON MULTICELLULAR CARRIERS 5 Sheets-#Sheet 3 Filed July 19, 1957 IN V EN TOR. Mars/7a f. Williamson 14o-LM M Afro/MEV AU8- 25, 1959 M. l. WILLLAMSQNA 2,901,157

MULTICELLULAR CARRIERS Filed July 19, 1957 5 Sheets-Sheet 4 A( f f INVENTOR. I Fzlg- 7 Mars/:qll WL/Immson ATTORNEY Aug. 25, 1959 M. WILLIAMSON 2,901,157

MULTICELLULR CARRIERS Filed .my 19; 1957 5 sheets-sheet s Fig. 9 Fig. /0

IN VEN TOR. Marsha/ l. Wz'l/zklmson 'Hrw-M *5.

l M A 'from/EY United States Patent Marshall LHWilliamson, New Haven, Conn., assignor to Federal,PaperB oad Cop'any, Inc., Bogota, NJ., a corporation `of New York ApplicationY July '19,19*'5'7., Seriali No. 673,067 6 claims. (c1. zza-42's) This invention relates to 'improvements in multicellular carriers of the twin-row type for the packaging, as a sales unit, of a plurality of `bottles or other receptacles arranged in two parallel rows.

The invention more particularly relates to the type of carrier in which individual cells are lformed in the top structure by deflection of portions of the top panel into a` vertical position so as to form a receptacle-engaging cell wall or liner, other portions of the `top structure remaining in a generally horizontal position to provide spacers for separating the receptacles of each row from one another.

Carriers of the aforementioned type are usually equipped with a central handle arranged between the two rows of receptacles. vIf this handle is extended above the tops of the receptacles, it interferes with the stacking'of loaded carriers into'display pyramids, a common practice in grocery stores. The handle also requires a substantial amount of board. t

Short handles terminating below the tops of thereceptacles are inconvenient `for the customer because of the narrow space between the rows of receptacles and is particularly uncomfortable to use if the receptacles are bottles sealed by a crown type cap. These caps have a coarselyV knurledfor serrated periphery comprising sharp pointswhich uncomfortablyl dig into the hand of the person lifting the carrier. t

The invention provides, amfong other features, an improvement, as ar result of which the space between the bottle caps fof the tworows of bottles is lautomatically increased when `the carrier is lifted up. t This is accomplished by a tapered design, in end view, of the'two halves of the bottlecarrier which are widest near the base of the cell apertures and narrowest at the bottom. The two Vhalves-are articulated to each other at or near the widest Aportion so that, when the vcarrier rests on' a flat surface, the two halves are Vspaced at the bottom. When lifted lup the two halves tilt relatively to Vthe handle, closing the space which previously `existed at the bottom; and increasing the space between the two rows of the bottle tops, whereby an adequate and comfortable spacefor the rhand of the person carryingfthe device is gained.

2,901,157 Patented Aug. 25, 1959 ice 2 stantially reduced if the center. of the load is shifted towards the center.

These and' other objects, features and advantages of the invention will appear more fully from the detailed description showing, for the purpose of illustration, a preferred embodiment of the invention. The invention also resides in certain new andoriginal features of construction and a combination of elements hereinafter set forth and claimed.

Although the characteristic features of this invention which are believed to'be novel will be particularlypointed out in the claims appended hereto, the invention itself, its objects and advantages, and the manner in which it may be carried out, may be betterl understood by referring to the following description, taken in connection with the accompanying drawings forming a part of it, in which: t

Figure l is a plan View of a cut and scored flat blank from which a twin-row carrier embodying the present invention may be formed, the inside surface facing the observer;

Figure 2 is a plan view of the blank of Figure l after certain folding and gluing operations converting the blank into a flat collapsed tubular structure;

Figure 3 is a perspective view of the tubular structure of Figure 2 after expansion, preparatory to the formation of the cells; K

Figure 4 is a perspective view of the structure of Figure 3 after formation of the cells; Y

Figure 5 is a perspective view of the multicellular structure of Figure 4 inc'ombination with a handle, ready for loading with bottles or other receptacles or articles of merchandise,

Other improvements involve an'automatic vshift inthe Wheny the carrier i's lifted-up', agreater portion `of the "'4 load-is carried `by the bottom pancladjacen't the handle wall structure,-therebygrelieving the louter wall -structure of a `portion 'offtlzie load.` A'lfhis is anfjimportant advantage in a construction in which the cellular to'p structure isjjoined-t othe inner wallsgbyfaglue lap. 'The load sustainedfbytheouter walls is transferred to' the handle via the cellular top structureland the glue lap and there is a `tendency-of -the glue lap-to pull away from the inner Figure 6 is an end elevation of the multicellular structure of Figure 4 in a'v position in which the structure rests on a at surface;

Figure 7V is an end elevation ofthe structure of Figure 6 after lifting up from the supporting surface;

Figure f5- is a perspective View illustrating the bottle separation produced by the lifting up. of the multicellular structure; and g Figures 9` and l0 are end elevations of multicellular structures ofthe type shown in' Figure 4, having center walls of different height.

In the' following description and in the claims various details will be identiedb'y speciiic names for convenience. The names however are intended to be generic in their application. Corresponding reference characters refer to corresponding parts inthe several figures of the drawings.

The drawings accompanying, and forming part of, this specification disclose certain specific details of the invention for the purpose ofexplanation of its broader aspects, but it is understood that the details may be modified in various respects without departure from the principles of the invention and Athat the invention may be applied to otherstructues than-the enesshev'vn. y

The' blank A of Figure l consists of suitable foldable sheet material s'uclras paperfb'oad.V The blank is rectangular in outline and `may be Outland scored, inzm'ultiple, on automatic 'cutting and creasing machines. The several constituent -parts of the blank' are' Aset apart 'by fold lines and cuts. f

The blank A comprises ag'lu'e lap l1, an' upper inner wall'p'anel 12,5avtp wall panel 13, an o'uter'wall panel i4,

abottom panel 15, aninn'er wall panel 16, afu'riher inner v wall panel "19, fa4 furtber' top panel V2l), a yfurther upper` walls. The tendency of theglue lap pulling away is subinner wall panel Z, and afurtllergluelap 22. The vari; ous panels are articulated to one another alng'substlan- 'tially .parallelnfold lines-of which. 23 may be termedy a glue lap fold line, 24 and 25 top: `fold lines, 2'6tand-2'7 bottom fold 4linesgZS a'center partition ridgerfold line,

structure A' 3 29 and 30 bottom fold lines, 31 and 32 top fold lines and 33 a further glue lap fold line.

The width of the

top panels

13 and 20, measured between their respective

top fold lines

24, 25, and 31', 32, is equal to the width of the bottom panels I and 18, measured between their respective

bottom fold lines

26, 27 and 29, 30. These dimensions, as will later be seen, permit the blank to be collapsed at in glued condition.

The

inner wall panels

16 and 17 are subdivided into

upper portions

34, 35 and

lower portions

36, 37 by intermediate folding `

scores

38 and 39, the significance of which will appear later.

The

top panels

13 and 20 are traversed lby cuts and fold lines permitting the formation of individual merchandise receiving cells therein. These cuts and fold lines may be identical for all the cells, and it will be sufcient to describe the configurations within the top panel 13, it being understood that top panel 20 is'of the same layout.

Cell cuts 40, 41 and 42 extend across the top panel and continue beyond the

top fold lines

24 and 25 into the body of the outer wall panel 14 and of the upper inner wall panel 12, respectively. The cell cuts terminate at relatively short

transverse cuts

43, 44, 45, 46, 47, 48. The

transverse cuts

43, 45 and 47 are substantially in line with the glue lap fold line 23 and terminate at

apex points

49, 50, 51, 52, 53 and 54. Similar apex points 55, 56, 57, 58, 59 and 60 mark the ends of the opposite

transverse cuts

44, 46 and 48. An additional fold line 61 may be provided in line with the apex points 55, 56, 57, 58, 59 and 60, but this fold line 61 is optional.

rPhe area of board on either side of the cell cuts 40, 41 and 42 is circumscribed by fold lines of a generally polygonal, somewhat elongated outline. These fold lines comprise

diagonal lines

62, 63, 64, 65, 66 and 67 extending from the respective apex points 49, 50, 51, 52, 53 and 54. Similar

diagonal fold lines

68, 69, 70, 71, 72 and 73 extend from the apex points 55, 56, 57, 58, 59 and 60. The diagonal fold lines extend at an angle of substantially 45 degrees to the

top fold lines

24 and 25.

Further fold lines

74, 75, 76, 77, 78 and 79 extend from the ends of the diagonal fold lines and lead to

peak points

80, 81, 82 and 83. Corresponding fold lines within the other half of the top panel are numbered 84, 85, 86, 87, 88 and 89.

It is readily seen that the diagonal fold lines form the sides of

trapezoidal panel portions

90, 91, 92 Iand 93, above which substantially

triangular panel portions

94, 95, 96 and 97 arise. The peaks of the triangle meet at the peak points 81 and 82 in the preferred form of cell construction illustrated in the drawings. A central fold line 98 extends down the center of the top panel 13. Auxiliary fold lines 99, 100, 101, 102, 103 and 104 may be provided to facilitate the formation of the cell structure later to be described.

The construction of a multicellular box from the blank A of Figure 1 may proceed by treating both ends of the blank substantially alike, as follows:

Adhesive a is first applied to the underside of the

glue laps

11 and 12 and the blank is then folded along the

top fold lines

24 and 32 to bring the

glue laps

11 and 22 into a position over the

top wall panels

13 and 20, respectively. Next, the ends of the blank are folded about the fold lines 26 and 30 to bring the

glue laps

11 and 22 into adhesive engagement with the

lower portions

36 and 37 of the inner walls.

The folding operations produce a at collapsed tubular shown in Figure 2. The collapsed structure A may be stored and shipped in Hat condition, requiring a minimum of space, and may be set up into hollow multicellular box form by a few relatively simple folding operations which will now be described.

The collapsedstructure A is readily expanded and 17 lie back to back for their entire extent including the

lower portions

36 and 37. The

top panels

13 and 20 are parallel to the

bottom panels

15 and 18. The

side wall panels

14 and 19 are parallel to the

inner wall panels

16 and 17. As previously stated, the width of the top panel is equal to the width of the bottom panel. This construction permits the structure of Figure 3 to be prefabricated in dat collapsed condition and, also, to be recollapsed, if that should be desired.

In the structure shown in Figure 3 individual cells are formed by downfolding of the portions of the top panels which lie immediately adjacent the

respective cell outs

40, 41 and 42. The board is readily folded at the

diagonal fold lines

62, 63, 64, 65, 66 and 67 and at the corresponding fold lines on the

other side

68, 69, 70, 71, 72 and 73 and -thereafter assumes a substantially vertical position with respect to the bottom panel, as shown in Figure 4. The

auxiliary fold lines

99, 101 and 103, visible in Figure 4, and the

auxiliary fold lines

100, 102 and 104, which are not visible, aid in the folding of the board into vertical position.

The cell forming operation causes the

points

80, 81, 82 and 83 to rise as peaks above the remainder of the top panel. The

triangular portions

94, 95, 96 and 97 assume a slanted position by reason of which the

top fold lines

24 and 25 are drawn together to assume a distance T (Figure 6) less than the original width of the top panel which was equal to the width B of the bottom panel.

As a further consequence of the formation of the cells, the upper portion of the walls assume an inwardly slanted position. Thus the upper

inner wall panels

12 and 21, which previously lay liat against the

inner wall panels

16 and 17, are separated therefrom as clearly seen in Figfolded along the center partition ridge fold line 28. The

expanded structure s shown in Figure 3. Y u y In the expanded structure the inner wall panels 16 and ures 4 and 6. Similarly the corresponding upper portion of the

outer walls

14 and 19 is drawn inwardly to form a slanted position with regard to the lower portion of the

outer wall panels

14 and 19.

The cell structure which is mainly contained inthe top panels, but also extends into the uppery portions of the side walls, resembles a mansard roof in end view, as is clearly apparent from Figure 6. This shape causes the cells to open to a maximum dimension C measured at the widest point, substantially at the level of the 'intere mediate folding scores 23, Y33, opposite which the optional fold lines 61 lie. In the event the fold lines 61 are omitted, the outer walls are arched or bowed and the dimension C is measured between the respective

transverse cuts

44, 46, 48 and the glue lap fold line 23, coinciding with the

transverse ents

43, 45, 47.

Referring to Figure 6, the

wall panels

14 and 36 are upwardly and outwardly slanted with regard to the bottom panel 15. Likewise, the lower portions of the

Wall panels

37 and 19 are outwardly and upwardly slanted with respect to the bottom panel 18.

Since both cell structures are hingedly connected at the intermediate folding scores 38, 39, the

lower portions

36, 37 of the inner wall panels separate to form a space S between them.

Figure 6 shows the cellular structure to be loaded with

bottles

105, 106 whose

axes

107 and 108 are vertical as long as the structure rests on a at substantially horizontal supporting surface 109. The bottles are snugly held within the vertical wall portions of the cells and are readily inserted since the dimension C is larger than the diameter of the bottles. Similarly, the distance between the

peaks

80, 81, 82 and 83 is larger than the bottle diameter due to the fact that, as a geometrical necessity, these points are spaced farther than opposite surfaces of the vertical cell walls. v

In the position shown in Figure 6 the weight of the bottles is equally distributed over the surface of the

bottom panels

15 and 18 as indicated by the diagram 110 in which the load is plotted vertically and in which the horizontal axis represents the width of the bottom panel, or the bottle diameter. The resultant or total load is represented by the centrally disposed arrow L.

If the structure is lifted upby a force F, as indicated in Figure 7, the two halves of the carrier tilt relatively to each other about the intermediate folding scores 38, 39 until the

lower portion

36, 37 of the

inner walls

16 and 17 rest against each other. In this condition the bottorn panels and 18 are tilted.

Since each cellular structure essentially represents a parallelogram in end elevational View, its

outer walls

14 and 19 tend to sag slightly causing the

bottom panels

15 and 18 to separate somewhat from the bottoms of the bottles near the

outer walls

14 and 19, as is visible at 111 and 112 in Figure 7. As a result, a shift occurs in the load distribution which is represented by the diagram 113. The diagram shows that the load is ncarried predominantly near the

inner walls

16 and 17. The resultant load L, which was centrally disposed in the diagram 110 of Figure 6, was shifted an appreciable distance towards the

central partition

16, 17 Inthe position shown in Figure 7 the

outer walls

14 and 19 carry relatively little of the total load. As a result, less load is transmitted through the cellular top structure to the glue lap and the danger of separation of the

glue laps

11 and 22 from the inner wall structure is greatly reduced. Y p

The axes of the bottles are tilted outwardly in Figure 7, thus providing increased clearancer between the tops of the bottles. This is also seen in Figure 8 where the crown caps 114 and 115 of the center bottles are spaced a safe and comfortable distanceV from the hand 116j of the person lifting the carrier. The carrier may be lifted either by an attached handle, as shown in Figure 8, or by a suitable hand aperture in the

inner wall structure

16, 17.

When the loaded multicellular structure of Figure 7 is placed on a iiat surface, the multicellular units again separate and assume the position shown in Figure Figure 5 illustrates a preferred form of attachable and detachable handle for the multic'ellular structure A of Figure 4. The handle 117 forms the subject matter of a copending application Serial No. 672,991, iiled July l9, 1957, and consists, essentially, of a single blankof paperboard folded back on itself along a top fold line 118.

The handle is provided lwith flaps 1 19 articulated along flap fold lines 120. The'ilaps are foldedA back upon the handle, while the handle is in flat condition, whereafter the handle is creased along Vertical fild line-s 121. In this condition the flaps 1 19 cannot unfold, since they are tightly drawn against thebody of the handle, Vthe flap fold line 120 being bent at eachvertical fold line 121.

The handle 117 is inserted into the central cells and hooks under the walls of the central cells.

In order to facilitate the engagement of the handle with the walls of thejcentralcells, the blank maybe provided with a cutout 123 providing a recessed lower edge 122 (Figure 4) within the central cells. The cutout provides a substantially horizontal engaging edge 122 for the handle in the position in which, the halves of the carrier are tilted as shown V,in Figure 7. In this position the bottom edges 124 of the cell webs arel slanted, but the cutout 123 provides a horizontal engaging edge portion for the handle.

Figures 9 and 10 illustrate minor modifications of the blank of Figure l. In Figure 9 the

inner walls

16 and 17 extend only to the hinge axis between the two cellular structures. In this form the center partition ridge fold line 2S may be considered to coincide with the hinge line provided by the intermediate folding scores 38, 39. In the form shown in Figure l0 the

inner walls

16 and 17 are taller than in Figure 9, but lower than in Figure 4. In this modification the center partition ridge fold line 28 is approximately at the same level as the

top fold lines

24 and 32 and the two cellular units are articulated to each other along intermediate folding scores 38, 39.

What is claimed is:

1. A multicellular llat collapsible folding box of the twin-row style formed from a single blank of board and comprising two tubular structures arranged side by side, each structure comprising a bottom panel; an outer side wall and an inner side wall articulated to the .bottom panel along bottom fold lines, the inner side wall comprising an upper wall panel and a lower wall panel; a top panel articulated to the side walls along top yfold lines, the top panel being arched to rise above said top lfold lines and having cells inrit, the mouth of the cells extending beyond said topfold lines into the* body of -said sidewalls, said cells including depending cell walls integral with said top panel and `depending therefrom at the cell mouth towards the bottom panel, eachk of the inner side walls of the two structures including an intermediate folding score intermediate of, and substantially parallel to, said top and bottom fold lines to which intermediate folding score said cell apertures extend, each of said inner side walls further comprising a glue lap `articulated to said upper wall panel and adhered to the lower wall panel adjacent said intermediate folding score, the width of the bottom panel measured between the bottom fold lines being less than the width of the structure measured at the level of the intermediate folding score, said two structures being pivotally movable relatively to each other at said intermediate folding score for freedom of the structures to tilt towards each other when the box is centrally lifted up, in which event the bottom panels assume slanted positions and the cell axes tilt outwardly, and for freedom to tilt in the opposite direction when the bottom panels are placed on a flat support, in which event the bottom positions of the two units automatically separate.

2. A multicellular flat collapsible Vfolding box of the twin-row sty-le formed from a single blank of board and comprising two tubular structures arranged side by side, each structure comprising a bottom panel; an outer side wall and an inner side wall articulated to the bottom panel along bottom fold lines, the inner side wall comprising an upper wall panel and a lower wall panel; a top panel arf ticulated to the sidewalls along top fold lines, the width of the top panel in flat condition being equal to the width of the bottom panel, width being measured between the respective bordering fold lines, the top panel Ibeing arched to rise above said top `fold lines and having cells in it, the mouth of the cells extending beyond said top lfold lines into the body of said side walls, said cells including depending cell walls integral with said top panel and depending therefrom at the cell mouth towards the bottom panel, each of the inner side walls of the two structures including an intermediate folding score intermediate of, and substantiallyV parallel to, said top and bottom fold lines to which intermediate folding score said cell apertures extend, each of said inner side walls `further cornprising a glue lap articulated to said upper wall panel and adhered to the lower wall panel adjacent said intermediate folding score, the width of the bottom panel being'less than the width ofthe structure measured at the level of the intermediate folding score, and greater than the distance between the top fold lines when the top panel is in archedposition, said two structures being pivotally movable relatively to each other at said intermediate folding score yfor freedom of the structures to tilt towards each other when the box is centrally 'lifted up, in which event the bottom panels assume slanted positions and the cell axes tilt outwardly, and for freedom to tilt in the opposite direction when the bottom panels are placed on a flat support, in which event the bottom portions of the two units automatically separate.

3. A multicellular at collapsible folding box of the twin-row style formed from a single blank of board and comprising two tubular structures arranged side by side, each structure comprising a bottom panel; an outer side Wall, and an inner side wall articulated to the bottom panel along bottom fold lines; a top panel articulated to the outer side wall along a top fold line, an upper `inner wall panel articulated to said top panel along a further top fold line; and a glue lap articulated to said upper inner wall panel along a further glue lap fold line and adhered to the inner side wall, the top panel being arched to rise above said top fold lines' and having cells in it, the mouth of the cells extending beyond said top fold lines into the body of said side walls, said cells including depending cell walls integral with said top panel and depending therefrom at the cell mouth towards the bottom panel, the inner side Walls of the two structures being taller than the outer side walls and being articulated to each other along a center partition ridge fold line, each of the inner side walls including an intermediate folding score intermediate of, and substantially parallel to, said top and bottom fold lines, to which intermediate folding score said cell apertures extend, said glue laps being adhered to said inner walls adjacent said intermediate folding score, said further top fold line being in substantial coincidence with said intermediate folding score, the width of the bottom panel measured between the bottom fold lines being less than the width of the structure measured at the level of the intermediate folding score, said two structures being pivotally movable relatively to each other at said intermediate folding score for freedom of the structures to tilt towards each other when the box is centrally lifted up, in which event the bottom panels assume slanted positions and the cell axes tilt outwardly, and for freedom to tilt in the opposite direction when the bottom panels are placed on a flat support, in which event the bottom portions of the two units automatically separate.

4. A multicellular folding box as claimed in claim 3 in which the inner side walls are provided with a finger grip aperture below said center partition ridge fold line and above said intermediate folding score.

5. A multicellular dat collapsible folding box of the twin-row style formed from a single blank of board and comprising two tubular structures arranged side by side, each structure comprising a bottom panel, an outer side wall panel articulated to said bottom panel along an outer bottom fold line, a top panel articulated to said outer side wall panel along a top fold line, an upper inner side wall panel articulated to the top panel along a further top fold line, a glue lap articulated to said upper inner side wall panel along a glue lap fold line, and a lower inner lside wall panel articulated to said bottom panel along an inner bottom fold line, the lower inner wall panels of the two structures being articulated to each other along a center ridge fold line, the top panel of each structure being arched to rise above said top fold lines and having cells in it, the mouth of the cells extending beyond said top fold lines into the body of-the outer and of the upper inner side walls, said cells including depending cell walls integral with said top panel and depending therefrom at the cell mouth towards the blottom panel, said glue laps being adhered to the inner side walls adjacent said center ridge fold line to which intermediate folding score said cell apertures extend, the glue lap fold line being in substantial coincidence with said center ridge fold line, the width of the bottom panel measured between the bottom fold lines being less than the width of the structure measured at the level of the intermediate folding score, said twok structures being pivotally movable relatively to 'each other at said intermediate folding score for freedom of the structures to tilt towards each other when the box is centrally lifted up, in which event the bottom panels assume slanted positions and the cell axes tilt outwardly, and for freedom to tilt in the opposite direction when the bottom panels are placed on a at support, in which event the bottom portions of the two units automatically separate.

6. A multicellular iiat collapsible folding box of the twin-row style formed from a single blank of board and comprising two tubular structures arranged side by side, each structure comprising a bottom panel; an outer wall panel articulated to said bottom panel along a bottom fold line, said outer wall panel having a lower portion and an upper portion, said two portions being articulated to each other along an intermediate outer folding score parallel to said bottom fold line, lthe lower portion being outwardly slanted and the upper portion being inwardly slanted; a top panel articulated to said upper portion along a top fold line; an upper inner wall panel articulated to said top panel along a further top fold line; a glue lap articulated to said upper inner wall panel along a glue lap fold line; a lower'inner wall panel articulated to said bottom panel along a further bottom fold line, said lower inner wall panel also being outwardly slanted and having said glue lap adhered to it in a position in which the glue lap fold line has substantially the same distance from the bottom panel as the said intermediate folding score, the lower inner wall panels being articulated to each other along a center ridge fold line, said top panel being arched to rise above said top fold lines and having cells in it, the mouth of the cells extending beyond said top fold lines to said intermediate folding score and said glue lap fold line respectively, said cells including depending cell walls integral with said top panel and depending therefrom at the cell mouth towards said bottom panel, the width of the bottom panel measured between the bottom fold lines being less than the width of the structure measured at the level defined by said intermediate folding score and said glue lap fold line, said two structures being tiltablerelatively to each other about a tilt axis substantially coinciding with said glue lap fold lines for freedom of the structures to tilt towards each other when the box is centrally lifted up, in which event the bottom panels assume slanted positions and the cell axes tilt outwardly, and for freedom to tilt in the opposite direction when the bottom panels are placed on a iiat support, in which event the bottom portions of the two units automatically separate.

References Cited in the file of this patent UNITED STATES PATENTS