US20060124716A1

US20060124716A1 - Bulk bin with auto-closing bottom

Info

Publication number: US20060124716A1
Application number: US11/301,438
Authority: US
Inventors: Benjamin Quaintance; Mark Wisecarver
Original assignee: Individual
Current assignee: International Paper Co
Priority date: 2004-12-14
Filing date: 2005-12-13
Publication date: 2006-06-15
Also published as: MX2007007057A; EP1824745A1; AU2005317178A1; CA2590291A1; EP1824745A4; WO2006065874A1; BRPI0517185A

Abstract

A bin (10, 40, 50, 70, 80) has an auto-closing bottom and can be manufactured and shipped and stored in a flattened configuration and moved to an open expanded configuration at a point of use. The bin has opposed sidewalls (11, 12) and opposed end walls (13, 14 and 15, 16) and major bottom flaps (18, 19) on the sidewalls and minor bottom flaps (20, 21 and 22, 23) on the end walls. The flaps automatically move to their closed position when the bin is moved from its flattened configuration to its expanded configuration. A connecting web (25-28, 43) is foldably connected between each major bottom flap and an adjacent first side edge of an adjacent minor bottom flap, and adjacent side edges of the minor bottom flaps are foldably interconnected (29, 30 or 44), so that when the sidewalls and end walls are moved from their flattened configuration to their open expanded configuration, the major and minor bottom flaps automatically fold inwardly toward one another to close the bottom of the bin.

Description

This application claims the benefit of U.S. provisional application Ser. No. 60/636,073, filed Dec. 14, 2004.

TECHNICAL FIELD

This invention relates to containers, and more particularly to large bulk bins for shipping and storing product in bulk quantities.

BACKGROUND ART

Many products, such as, e.g., fresh meat and poultry, are commonly stored and shipped in bulk bins constructed of corrugated paperboard. These bins typically have either four, six or eight sides and since they are designed to hold 2,000 pounds or more of product they are constructed of heavy-duty materials. They are usually shipped and stored in a flattened condition and manually set up into an expanded position at the point of use.
The sidewalls in a four-sided bin are relatively wide and can experience substantial outward bulge, resulting in pallet overhang and interfering with storage and handling of the bins. To minimize this bulge, eight-sided bulk bins of the type disclosed in U.S. Pat. No. 6,588,651, for example, are commonly used. Because of the narrower sidewalls in an eight-sided bin, less outward bulge is experienced. However, manual set up of an eight-sided bulk bin can be relatively difficult because of the more complex bottom flap construction. Six-sided bins, on the other hand, offer some of the advantages of both four-sided bins and eight-sided bins, in that they experience less sidewall bulge than a four-sided bin and are easier to set up than an eight-sided bin.
Whether constructed of four, six or eight sides, due to their heavy construction these bulk bins can be difficult to set up. In practice, the flattened bins are turned upside down and supported on the floor while they are expanded into a tubular configuration and the bottom flaps folded into operative relationship, after which the bin is inverted into an upright position and placed on a pallet to receive product. However, when the bin is to be used for containing a food product, contact between the top of the bin and the floor is prohibited. This obviously presents a problem with regard to setting up the bin.
It would be advantageous to have a bulk bin that is easy to set up and whose bottom flaps can be moved to closed position automatically, without having to invert the bin and rest it on its top end to close the bottom flaps.

DISCLOSURE OF THE INVENTION

The present invention solves the aforementioned problems by providing a six-sided bin with a bottom flap construction that automatically moves into closed position when the bin is supported on its bottom end and moved from its flattened condition to its expanded condition. Thus, the flattened bin of the invention can be supported in an upright position with its bottom end resting on a pallet, and the sidewalls then moved into an expanded open position, with some downward pressure exerted against the bottom flaps, whereupon the bottom flaps automatically move into operative closed position, thereby preparing the bin for use without requiring any further steps. This eliminates the steps required in the prior art of first orienting the flattened bin in an upside down position, with its top resting on a floor, and then manually folding the bottom flaps to their operative position, followed by inverting the bin to an upright position and then placing it on a pallet.
The bin of the invention comprises opposed sidewalls each having a top edge, opposite side edges and a bottom edge, and end walls connected to respective opposite side edges of the sidewalls, said end walls each having a top edge, a bottom edge, and opposite side edges. A major bottom flap is foldably connected to the bottom edge of each of the sidewalls, and each major bottom flap has opposite side edges. A minor bottom flap is foldably connected to the bottom edge of each said end wall, and said minor bottom flaps each have opposite first and second side edges. Connecting webs interconnect said major and minor bottom flaps, including a connecting web foldably connected between each side edge of each major bottom flap and a respective first side edge of an adjacent minor bottom flap, so that when the sidewalls and end walls are moved from a flattened condition of said bin to an open expanded position, the major and minor bottom flaps automatically fold inwardly toward one another to close the bottom of the bin.
In a first preferred embodiment, the bin has six sides, comprising two opposed parallel sidewalls and two opposed pairs of diagonally oriented end walls. A major bottom flap is foldably connected to the bottom edge of each of said opposed sidewalls, and a minor bottom flap is foldably connected to the bottom edge of each of said end walls. Generally triangularly shaped connecting webs are foldably connected between the side edges of the major bottom flaps and the respective adjacent side edges of adjacent minor bottom flaps, and generally triangularly shaped glue flaps are connected between the adjacent side edges of adjacent minor bottom flaps. In its flattened condition, the major and minor bottom flaps and connecting webs extend outwardly of the bin. To erect the bin, it is placed upright on the flaps and the sidewalls are expanded or opened up to a tubular, generally hexagonal configuration. This movement of the side and end walls causes the major and bottom flaps to fold inwardly, closing the bottom of the bin.
In a second preferred embodiment, the bin also has six sides, comprising two opposed parallel sidewalls and two opposed pairs of diagonally oriented end walls. A major bottom flap is foldably connected to the bottom edge of each of the opposed sidewalls, and a minor bottom flap is foldably connected to the bottom edge of each of the end walls. Generally triangularly shaped connecting webs are foldably connected between the side edges of the major bottom flaps and the respective adjacent side edges of adjacent minor bottom flaps, and between the adjacent side edges of adjacent minor bottom flaps. In its flattened condition, the major and minor bottom flaps and connecting webs extend outwardly of the bin. To erect the bin, it is placed upright on the flaps and the sidewalls are expanded or opened up to a tubular, generally hexagonal configuration. This movement of the side and end walls causes the major and bottom flaps to fold inwardly, closing the bottom of the bin.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing, as well as other objects and advantages of the invention, will become apparent from the following detailed description when taken in conjunction with the accompanying drawings, wherein like reference characters designate like parts throughout the several views, and wherein:
FIG. 1 is a top perspective view of a six-sided bulk bin according to the invention supported on a pallet.
FIG. 2 is a top plan view of the bin and pallet of FIG. 1.
FIG. 3 is a plan view of a blank for making a first embodiment of the bin shown in FIGS. 1 and 2.
FIG. 4 is a perspective view of the die-cut blank as fed into the folding rails of a machine for folding and gluing up the blank during its manufacture.
FIG. 5 is a perspective view of the blank with the angled glue flaps folded up at approximately a 60° angle, and glue applied to adjacent minor bottom flap panels.
FIG. 5A is an enlarged perspective view of the circled portion in FIG. 5, showing the glue applied to the minor bottom flap panels.
FIG. 6 is a perspective view showing the main panels as they would appear while being folded over by the folding rails.
FIG. 7 shows the main panels folded further and depicting how they engage and push the angled glue flaps down.
FIG. 8 shows the main panels nearly folded into their operative relationship, with the glue flaps sandwiched between them.
FIG. 9 is a perspective view of the manufactured bin, in its flattened condition as stored and shipped, with the panels folded and glued in operative position.
FIG. 10 is an enlarged plan view of the flattened bin, as manufactured.
FIG. 11 is an enlarged top perspective view of the bin of FIG. 10, depicting the bin in an upright position with its bottom end oriented downwardly and the sidewalls being opened up into an expanded condition.
FIG. 12 is a top view showing the bin of FIG. 11 in a nearly fully erected condition, with the bottom flaps moved into their nearly fully folded operative positions.
FIG. 13 is a top view of the bin of FIG. 12, shown in its fully erected condition.
FIG. 14 is a plan view of a blank for making a second embodiment of the bin of the invention, wherein elliptical creases are formed in the sidewalls for producing controlled and predictable bulge, reinforcing tape is provided in the sidewalls, and the connecting webs between the major and minor bottom flaps are crushed to minimize their tendency to return to their unfolded positions.
FIG. 15 is a plan view of a blank for making a third embodiment of the bin, similar to the embodiment shown in FIG. 3, but the orientation of the cuts separating the glue flaps from the adjacent minor flaps is opposite that shown in FIG. 3.
FIG. 16 is a plan view of a blank for making a fourth embodiment of the bin, wherein the blank has some features of the embodiment in FIG. 14, i.e., elliptical creases in the sidewalls, reinforcing tape, and crushed connecting webs, and some features from the embodiment of FIG. 15, i.e., the orientation of cuts separating the minor flaps from each other.
FIG. 17 is a top plan view of a blank for making a fifth embodiment of the invention, wherein the major bottom flaps overlap in the erected bin, and all of the bottom flaps are interconnected by connecting webs, rather than some of them being separated by a cut or slit as in the previous embodiments.
FIG. 18 is a top plan view of a blank for making a sixth embodiment of the invention, essentially the same as the embodiment shown in FIG. 17, except that the bottom flaps do not overlap in a bin erected from the blank.
FIG. 19 is a greatly enlarged fragmentary plan view of a blank for making a bin according to the invention, showing a portion of the sidewalls and flaps and illustrating a detail of the cuts and crushed areas that resist initiation of tearing of the vertical scores between the sidewalls.
FIGS. 20A-20G depict steps that may be followed in setting up the bin of FIGS. 17-19.

BEST MODES FOR CARRYING OUT THE INVENTION

The bulk bin of the invention is indicated generally at 10, and comprises opposed parallel sidewalls 11 and 12, and two opposed pairs of angularly oriented end walls 13, 14 and 15, 16 connected between respective opposite side edges of the sidewalls, defining a six-sided container having a generally hexagonal shape in transverse cross-section and adapted to fit on a 48×40 inch pallet 17.
Major bottom flaps 18 and 19 are foldably connected to the bottom edges of respective opposite sidewalls, and minor bottom flaps 20, 21, 22 and 23 are foldably connected to the bottom edges of respective end walls.
Generally triangularly shaped connecting webs 25, 26, 27 and 28 are foldably connected between the side edges of the major bottom flaps 18 and 19 and the respective adjacent side edges of adjacent minor bottom flaps 20, 22 and 21, 23, respectively. Generally triangularly shaped glue flaps 29 and 30 are foldably connected to a side edge of respective minor flaps 22 and 20.
In the embodiment of FIG. 3, partial end wall panels 16A and 16B are at opposite ends of the blank, with partial minor bottoms flap 23A and 23B foldably joined to the respective bottom edges thereof. The glue flap 29 is separated at one of its edges from partial minor bottom flap 23B by a cut 31, and is integrally foldably connected at its opposite edge with minor bottom flap 22. Glue flap 30 is similarly separated from minor bottom flap 21 by cut 32 and is integrally foldably connected with minor bottom flap 20. Folding scores or creases 33 are made in the fold lines at opposite sides of the connecting webs and at the folded connection of the glue flaps to facilitate folding of the bottom flaps as the bin is being erected. Folding action can be enhanced by making cuts or perforations 33′ along a part of the length of the creases.
FIGS. 4-9 depict the steps followed in completing the manufacturer's glue joint in a bin made from the blank shown in FIG. 3. FIG. 4 shows the blank laid out flat before any folding operations are performed. In FIG. 5 the angled glue flaps 29 and 30 are shown folded upwardly approximately 60° from the plane of the blank. Glue 34 is then applied to the adjacent minor bottom flaps 21 and 23B, as depicted in FIGS. 5 and 5A, followed by upward folding of the blank about a fold line 35 located generally centrally of the length of the blank, between the end walls 13 and 14, defining two substantially identical panel sections or halves A and B, each including a sidewall 11 or 12, adjacent end walls 13, 15 or 14, 16, and associated bottom flaps. Partial minor bottom flap 23B is also folded upwardly, as depicted in FIG. 6. Continued inward folding of the panel section A and partial minor bottom flap 23B results in contact between the angled glue flaps 29, 30 and the respective glued sections of partial minor bottom flap 23B and minor bottom flap 21, resulting in sandwiching of the glue flaps between the respective adjacent minor bottom flaps. The manufacturer's glue joint is then made by adhesively attaching adjacent overlapping edges of the partial end wall panels 16A and 16B and corresponding overlapping edges of the partial minor bottom flaps 23A and 23B.
It will be noted that the adjacent corners of minor bottom flap 21 and glue flap 30, and of partial minor bottom flap 23B and minor glue flap 29, between which the respective cut lines 32 and 31 extend, are respectively cut away at 36.
The assembled blank may then be placed in stacked compression, and shipped to a point of use. At the point of use, the flattened bin is stood on its bottom edge on a pallet and pressure exerted on the sidewalls to expand the side and end walls away from one another into a generally hexagonally shaped tubular configuration, as depicted in FIGS. 11 and 12. During this process, the major and minor bottom flaps automatically move into inwardly folding closing relationship over the bottom of the bin. With particular reference to the embodiment shown in FIGS. 12 and 13, it will be noted that the major bottom flaps are dimensioned so that they overlap slightly at their adjacent inner edges when the bin is fully erected. It should be understood, however, that these edges do not need to overlap and can be abutting or even spaced from one another. Alternate embodiments discussed hereinafter do not have overlapping bottom flaps. In this embodiment, these overlapped edges in conjunction with the particular interconnected relationship of the bottom flaps results in an over-center-like snap action of the flaps, tending to retain them in their operative inwardly folded relationship.
A second embodiment of the bin is indicated generally at 40 in FIG. 14. This embodiment has essentially the same inventive features as the FIG. 3 embodiment, and like parts are indicated by like reference characters. In addition, elliptically shaped creases 41 are formed in the side and end walls, reinforcing tape 42 is placed at predetermined spaced locations in the side and end walls, and the connecting webs 25′, 26′, 27′ and 28′ are crushed as indicated by the shading 43. The elliptical creases are similar to the arrangement shown in applicant's prior U.S. Pat. No. 6,588,651, and help obtain predictable and controlled bulging of the side and end walls. Crushing of the webs removes the natural springiness or memory of the material, resulting in the panels remaining more securely in their folded positions and tending less to spring back out to their unfolded positions.
A third embodiment of the bin is indicated generally at 50 in FIG. 15. This embodiment is substantially the same as the embodiment shown in FIG. 3, and like parts are indicated by like reference characters. The only difference between this embodiment and the FIG. 3 embodiment is that the cuts 31′ and 32′ separating the glue flaps 29′ and 30′ from respective adjacent minor bottom flaps are oriented oppositely and are on the opposite sides of the glue flaps from the arrangement shown in FIG. 3, whereby the glue flaps are separated from minor bottom flaps 20′ and 22′ rather than from flaps 21 and 23B as shown in the FIG. 3 embodiment.
FIG. 16 depicts a fourth embodiment 60 that has some features of the embodiment in FIG. 14, i.e., elliptical creases 41 and reinforcing tape 42 in the sidewalls, and crushed connecting webs 43, and some features from the embodiment of FIG. 15, i.e., the orientation of cuts 31′ and 32′ separating minor flap 22 from adjacent partial bottom flap 23B, and minor flap 20 from adjacent minor bottom flap 21, respectively. This embodiment otherwise is constructed and functions the same as the previous embodiment.
FIG. 17 depicts a fifth embodiment 70 wherein those parts corresponding to like parts in the earlier embodiments are indicated by like reference characters. In this embodiment the cuts 31 and 32 and associated cut away corners 36, and the glue flaps 29 and 30, are all omitted, so that not only are the major bottom flaps and adjacent minor bottom flaps interconnected by the connecting webs 43 as in the previous embodiments, but the glue flaps are replaced by connecting webs 44 that respectively interconnect adjacent minor bottom flaps 20″ and 21, and adjacent minor bottom flap 22″ and partial minor bottom flap 23B′, whereby all the bottom flaps are continuously interconnected by webs. Further, elliptical creases 41 are formed in only the two opposed sidewalls 11 and 12. In the latter regard, the elliptical creases may be included in only the two sidewalls as shown, or in all the sidewalls and end walls, or in none of them. Similarly, reinforcing tape 42 may be provided, or excluded, as desired or necessary. It will also be noted in this embodiment that major bottom flap 18 is cut away at its opposite corners as indicated at 45, defining a tab or protruding edge 46 as in the previous embodiments, whereby when the bottom flaps are folded inwardly to close the bottom of the bin, the tab overlaps with the edge 47 of opposite major bottom flap 19′.
A sixth embodiment 80 is illustrated in FIG. 18. This embodiment differs from the embodiment of FIG. 17 in that the corners of the major bottom flap 18′ are not cut away as at 36 in the FIG. 17 embodiment, whereby both flaps 18′ and 19′ terminate at their free end in a straight edge 47, and the major bottom flaps 18′ and 19′ do not overlap when they are in their inwardly folded operative positions.
As seen best in FIG. 19, the various embodiments of the bin illustrated and described herein can have semi-circular crushed areas 90 at the juncture of the vertical fold line 91 between adjacent sidewalls and end walls, the fold line 92 between the major and minor bottom flaps and their associated sidewall or end wall, and the fold line 33 between adjacent flaps. Additionally, the end of the diagonal cut 33′ extending to this juncture can be given an inverted J shape as indicated at 93. The crushed areas and/or the J shaped termination of the cuts 33′ resist initiation of tearing of the vertical scores 92.
A procedure for setting up a bin made from the blanks of FIGS. 17-19 is illustrated in FIGS. 20A-20G. FIG. 20A shows the bin 70 in its flattened condition, as manufactured, lying flat on a supporting surface. A person setting up the bin lifts the top end of the flattened bin, pivoting it about the bottom edges of the flaps, which remain in contact with the supporting surface. Downward pressure is then exerted against the bin, breaking the crease or fold between the sidewalls and the bottom flaps, as shown in FIG. 20B, and preferably by then bending the flaps in the opposite direction, as shown in FIG. 20C. The sidewalls are then opened up into a tubular shape, as shown in FIG. 20D, and by rocking the bin back and forth as shown in FIG. 20E the major bottom flaps, which are longer than the minor flaps, begin to fold inwardly. The minor bottom flaps are then kicked inwardly, as shown in FIG. 20F, and the bin settles down on the flaps, which are all folded inwardly to their operative positions, as shown in FIG. 20G. This entire process can be accomplished with the bin resting on a pallet, whereby the bin is now ready for use without requiring any further steps.
Although particular embodiments of the invention are illustrated and described in detail herein, it is to be understood that various changes and modifications may be made to the invention without departing from the spirit and intent of the invention as defined by the scope of the appended claims.

Claims

1. A bin having an auto-closing bottom and that can be manufactured and shipped and stored in a flattened condition and moved to an open expanded position at a point of use, comprising:

opposed sidewalls each having opposite side edges and a bottom edge;

opposed end walls connected to respective opposite side edges of the sidewalls, said end walls each having a bottom edge;

a major bottom flap foldably connected to the bottom edge of each said sidewall, said major bottom flaps each having opposite side edges;

a minor bottom flap foldably connected to the bottom edge of each said end wall, said minor bottom flaps each having opposite first and second side edges; and

a connecting web foldably connected between each side edge of each major bottom flap and an adjacent first side edge of an adjacent minor bottom flap, wherein said connecting webs interconnect said major and minor bottom flaps so that when the sidewalls and end walls are moved from a flattened condition of said bin to an open expanded position, the major and minor bottom flaps automatically fold inwardly toward one another to close the bottom of the bin.

2. A bin as claimed in claim 1, wherein:

there are two said sidewalls disposed in opposed, spaced apart, parallel relationship to one another, and there are two opposed pairs of angularly disposed end walls connected between respective opposite side edges of said sidewalls, defining a six-sided container having a generally hexagonal shape in transverse cross-section.

3. A bin as claimed in claim 2, wherein:

adjacent side edges of the minor bottom flaps on the bottom edges of adjacent end walls in at least one pair of end walls are foldably interconnected.

4. A bin as claimed in claim 3, wherein:

adjacent side edges of the minor bottom flaps on the bottom edges of one pair of adjacent end walls are separated from one another by a cut; and

the foldable interconnection between adjacent side edges of the minor bottom flaps on said one pair of adjacent end walls comprises a glue flap on one minor bottom flap adhesively attached to an adjacent minor bottom flap.

5. A bin as claimed in claim 1, wherein:

the major and minor bottom flaps have free edges opposite their folded connection with the respective sidewalls and end walls; and

the width of the major bottom flaps between their free edge and their folded connection is greater than the width of the minor bottom flaps between their free edge and their folded connection.

6. A bin as claimed in claim 5, wherein:

the connecting webs are generally triangularly shaped, having two sides converging to substantially a point at the juncture of the folded connections between adjacent major and minor bottom flaps.

7. A bin as claimed in claim 6, wherein:

the minor bottom flaps have generally a trapezoidal shape; and

the major bottom flaps have generally a rectangular shape.

8. A bin as claimed in claim 7, wherein:

9. A bin as claimed in claim 8, wherein:

adjacent side edges of the minor bottom flaps on the bottom edges of adjacent end walls in each pair opposed end walls are foldably interconnected.

10. A bin as claimed in claim 9, wherein:

the foldable interconnections between adjacent side edges of the major and minor bottom flaps comprise triangularly shaped webs.

11. A bin as claimed in claim 10, wherein:

the webs have two sides converging to substantially a point at the juncture of the folded connections between adjacent minor bottom flaps; and

the webs are crushed.

12. A bin as claimed in claim 1, wherein:

the bin is made of corrugated paperboard.

13. A bin as claimed in claim 1, wherein:

an area of said bin at said juncture of the folded connections is crushed.

14. A bin as claimed in claim 11, wherein:

the webs are connected to adjacent major and minor bottom flaps along a fold line, a fold-promoting cut is made in the fold line, and said fold-promoting cut terminates in a J shaped end adjacent said juncture.

15. A blank for making a collapsible paperboard bin that may be changed from a flattened condition for shipment and storage to an expanded open position at the point of use, wherein the container has an auto-closing bottom, said blank comprising:

an elongate, rectangularly shaped piece of paperboard having a plurality of spaced apart, parallel, transverse fold scores defining a plurality of adjacent, foldably interconnected wall panels having top and bottom edges, and including sidewall panels and end wall panels interposed between the sidewall panels;

a major bottom flap foldably connected to a bottom edge of each sidewall panel;

a minor bottom flap foldably connected to a bottom edge of each end wall panel; and

a connecting web foldably connected between adjacent side edges of each major bottom flap and an adjacent minor bottom flap.

16. A blank as claimed in claim 15, wherein:

there are two spaced apart said sidewall panels and a said end wall panel on each side of each said sidewall panel.

17. A blank as claimed in claim 16, wherein:

an end wall panel is at one end of the blank, followed by one of said sidewall panels, followed by two adjacent said end wall panels, followed by a second said sidewall panel, followed by another said end wall panel, followed by another end wall panel at a second end of the blank.

18. A blank as claimed in claim 17, wherein:

adjacent edges of adjacent minor bottom flaps on adjacent end wall panels are separated by a cut.

19. A blank as claimed in claim 18, wherein:

a glue flap is on one of said minor bottom flaps of each pair of adjacent end wall panels, adjacent said cut.

20. A blank as claimed in claim 19, wherein:

said end wall panels at opposite ends of the blank comprise partial end wall panels.

21. A blank as claimed in claim 20, wherein:

said sidewall and end wall panels and said major bottom flaps are generally rectangularly shaped, said minor bottom flaps are generally trapezoidally shaped, and said connecting webs and glue flaps are generally triangularly shaped.

22. A blank as claimed in claim 21, wherein:

said major and minor bottom flaps each have a free edge opposite their folded connection with a respective sidewall or end wall panel, and the width of the major bottom flaps between their folded connection and free edge is greater than the width of the minor bottom flaps between their folded connection and free edge.

23. A blank as claimed in claim 22, wherein:

said connecting webs and glue flaps each have two sides converging to substantially a point at the folded connections between respective adjacent major and minor bottom flaps and their associated wall panels.

24. A blank as claimed in claim 15, wherein:

said major bottom flaps are foldably interconnected with adjacent minor bottom flaps by connecting webs; and

said minor bottom flaps are foldably interconnected with adjacent minor bottom flaps by connecting webs.

25. A process for setting up a bin from a flattened configuration to an erected configuration, comprising the steps of:

providing a bin in a flattened configuration lying on a surface, wherein said bin, when erected, has opposed sidewalls and opposed end walls, a top end, and a bottom end with major and minor bottom flaps connected to the sidewalls and end walls, respectively, along a crease forming a fold line;

elevating the top end of the flattened bin, with the flaps resting on the surface;

causing the flaps to bend about said crease;

moving the sidewalls and end walls to open up the bin to an expanded tubular configuration;

rocking the bin back and forth on the major flaps to cause the major flaps to begin folding inwardly;

pressing the minor flaps inwardly; and

pushing down on the bin to cause the major and minor bottom flaps to fold to their fully closed positions.