Octagon shaped stackable flexible intermediate bulk container and method of manufacture

Abstract
A bulk bag comprises eight substantially identical side wall portions each containing a stiffening panel. A bottom wall is connected to the bottom edges of the side wall portions and may be provided with a discharge port. Alternatively, a discharge port may be provided in one of the side wall portions. The bulk bag may be provided with a top wall which may be either openable or secured in place. A pallet and/or lift loops may be provided for transporting the bulk bag and the contents thereof.
Description




TECHNICAL FIELD




The present invention relates generally to flexible intermediate bulk containers, also known as bulk bags, and more particularly to octagon shaped bulk bags which are adapted for stacking one on top of another.




BACKGROUND AND SUMMARY OF THE INVENTION




Over the past thirty years flexible intermediate bulk containers, commonly known as bulk bags, have come into widespread use for receiving, storing, transporting, and discharging flowable materials of all types. Although circular bulk bags are known, bulk bags are typically constructed from rectangular panels which are sewn together along their adjacent edges to define a bulk bag which is initially square or rectangular in horizontal cross section. Nevertheless, all bulk bags, whether initially square, rectangular, or circular in cross section tend to assume a circular configuration when filled due to the uniform pressure imposed by the contents of the bulk bag against the flexible fabric side walls thereof.




U.S. Pat. No. 4,903,859 discloses a bulk bag comprising four double layer side walls. Stiffeners formed from cardboard are inserted between the layers of the side walls thereby imparting sufficient rigidity to the container to permit its use with liquids. Although the bulk bag of the '859 patent has been generally well received, its utilization has been somewhat limited by the fact that it cannot be stacked.




Co-pending application Ser. No. 09/390,403 assigned to the assignee hereof (doing business as Composite Container Corp.) discloses an improvement over the bulk bag of the '859 patent. In application Ser. No. 09/390,403 there is disclosed a bulk bag having double layer side walls and vertically extending corner the side walls and wooden posts are received in the corner pockets to provide a bulk bag suitable for use with liquids which is stackable.




U.S. Pat. No. 5,076,710 discloses a baffle-type bulk bag wherein bridge panels or baffles are sewn across the four corners of a nominally rectangular bulk bag. The baffles prevent the side walls of the bulk bags from bulging outwardly when the bulk bag is filled, thereby retaining the filled bulk bag in a more or less rectangular cross-sectional configuration. The baffles may be provided with apertures which allow material to flow into and out of the corners of the bulk bag during filling and discharging operations.




Co-pending application Ser. No. 09/458,362 also assigned to the assignee hereof discloses a baffle-type bulk bag which is stackable. In the bulk bag of application Ser. No. 09/458,362, triangular stiffeners are provided in the triangular corners of baffle-type bulk bags. The stiffeners may be formed from various materials including plastic panels, panels formed from corrugated paperboard and similar materials, etc. The stiffeners may be provided with apertures aligned with the apertures of the baffles thereby permitting the flow of material into and out of the bulk bag during filling and discharging operations.




The present invention comprises an improvement over the bulk bags disclosed in the '859 and '710 patents and in the '403 and '362 patent applications which provides an octagon shaped bulk bag which is stackable. The use of the octagon shape in the construction of the bulk bag is advantageous in that it provides maximum stackability while eliminating the need for baffles and triangular stiffeners contained within the baffles.




In accordance with the broader aspects of the invention, there is provided a bulk bag comprising eight double layer side wall portions. Each double layer side wall portion receives a stiffening panel which extends substantially the entire length and width of the side wall portion. The stiffening panels used in the side wall portions of the bulk bag of the present invention may comprise corrugated plastic panels or similar panels made from other materials which are sufficiently resistant to bending.




The octagon shaped bulk bags of the present invention are adapted for mounting on pallets. The bulk bag may also be provided with lift loops. The bulk bags of the present invention have bottom walls which may include a discharge port. Alternatively, one of the side wall panels may be provided with a discharge port located at the lower end thereof. The bulk bags of the present invention may have an open top, or a suitable top closure may be provided. Suitable top closures useful in the practice of the invention include openable flexible panels, openable rigid panels, and permanently mounted panels including fill spouts.




In accordance with another aspect of the invention, there is provided an eight piece bulk bag side wall construction. The eight pieces are arranged in four sets each comprising an inner layer and an outer layer. The inner and outer layers are joined together by vertically extending seams which are spaced apart by a distance equal to approximately ⅛ of the circumference of the bulk bag, thereby forming four of the side wall portions. The opposite edges of the inner and outer layers comprising the four side wall assemblies are joined edge to edge to form the remaining four side wall portions of the bulk bag. A stiffening panel is positioned between the inner and outer layers of each side wall portion and at least the bottom edges of the side wall sections are sewn together to secure the stiffening panels therein.











BRIEF DESCRIPTION OF THE DRAWINGS




A more complete understanding of the invention may be had by reference to the following Detailed Description, when taken in conjunction with the accompanying Drawings, wherein:





FIG. 1

is a perspective view of an octagon shaped bulk bag incorporated in the present invention;





FIG. 2

is a perspective view of a side wall assembly useful in the practice of the invention;





FIG. 3

is an enlarged partial top view of the octagon shaped bulk bag of

FIG. 1

illustrating the joinder of adjacent side wall assemblies;





FIG. 4

is a top view of the octagon shaped bulk bag of

FIG. 1

;





FIG. 5

is a perspective view illustrating a first variation of the octagon shaped bulk bag of

FIG. 1

;





FIG. 6

is a view similar to

FIG. 5

in which certain component parts are shown in section more clearly to illustrate certain features of the invention;





FIG. 7

is a top perspective view illustrating a second variation of the bulk bag of

FIG. 1

;





FIG. 8

is a bottom perspective view of the bulk bag of

FIG. 7

;





FIG. 9

is a sectional view of the bulk bag of

FIG. 7

illustrating the use of liners in conjunction with bulk bags incorporating the invention;





FIG. 10

is a perspective view illustrating the stacking of octagon shaped bulk bags comprising the present invention;





FIG. 11

is a perspective view illustrating the folding of octagon shaped bulk bags of the present invention for return shipment; and





FIG. 12

is perspective view illustrating the positioning of several small size versions of the octagon shaped bulk bag of the present invention on a single pallet, and the stacking of pallets having several small size bulk bags positioned thereon.











DETAILED DESCRIPTION




Referring now to the Drawings, and particularly to

FIG. 1

thereof, there is shown an octagon shaped bulk bag


20


comprised in the present invention. The octagon shaped bulk bag


20


is characterized by an octagonal side wall


22


having a top or upper edge


24


and a bottom or lower edge


26


. The octagonal side wall


22


comprises eight substantially identical side wall portions


28


,


30


,


32


,


34


,


36


,


38


,


40


, and


42


. The side wall portions


28


-


42


, inclusive, are connected edge to edge to form the octagonal side wall


22


.




As is best shown in

FIG. 2

, the octagonal side wall


22


of the bulk bag


20


comprises four substantially identical side wall assemblies


50


. Each side wall assembly


50


comprises an outer layer


52


having a top or upper edge


54


, a bottom or lower edge


56


, and opposed side edges


58


and


60


. The side wall assembly


50


further comprises an inner layer


62


having a top or upper edge


64


, a bottom or lower edge


66


, and opposed side edges


68


and


70


. Each side wall assembly


50


comprising the bulk bag


20


is further characterized by a predetermined length, which is the vertical dimension, and a predetermined width, which is the horizontal dimension. The layers


52


and


62


are preferably formed from woven polypropylene fabric; however, other materials may also be used in the practice of the invention.




The outer layer


52


and the inner layer


62


comprising the side wall assembly


50


are joined by spaced apart vertically disposed seams


72


and


74


. The seams


72


and


74


of the side wall assemblies


50


define the side wall portions comprising the side wall


22


of the bulk bag


20


. The seams


72


and


74


also define stiffening panel receiving pockets


76


. Each stiffening panel receiving pocket


76


eventually receives a stiffening panel


80


therein. In the construction of the bulk bag


20


, the stiffening panel receiving pockets


76


are closed at the bottom or lower ends thereof by a bottom seam


82


.




The stiffening panels


80


of the present invention may be manufactured from plastic panels of the type sold by Coroplast of Dallas, Tex., under the trademark COREX™. Other types of plastic panels may also be used, depending upon the requirements of particular applications of the invention. The stiffening panels


80


may also be formed from various types of paperboard; fiberboard, including medium density fiberboard (MDF); cardboard; plywood; and other materials depending upon the ability of stiffening panels formed from such materials to resist bending.




Referring simultaneously to

FIGS. 1 and 2

, the top or upper end of each stiffening panel receiving pocket


76


and the top or upper edges of the outer and inner layers


52


and


62


may be permanently joined by a seam


84


. Alternatively, the top or upper ends of the stiffening panel receiving pockets


76


may be releaseably closed by fastening mechanisms


86


which may comprise hook-and-loop fasteners of the type sold under the trademark VELCRO®, buttons, or snaps. The use of the releaseable fasteners


86


allows the stiffening panels


80


to be removed from the stiffening panel receiving pockets


76


to facilitate folding of the bulk bag


20


for transportation and storage.




In the construction of the bulk bag


20


the four side wall assemblies


50


are connected edge to edge to form the side wall


22


. As is best shown in

FIG. 3

, the side edges


58


and


60


of adjacent side wall assemblies


50


are joined by seams


90


. Likewise, the adjacent edges


68


and


70


of the inner layers


62


are joined by seams


92


. As will be appreciated by those skilled in the art, the circumference defined by the joinder of the four inner layers


62


comprising the four side wall assemblies


50


must be somewhat less than the circumference defined by the four outer layers


52


in order to provide sufficient space between the outer layers


52


and the inner layers


62


to receive the stiffening panels


80


. For this reason, the seams


92


which join the inner layers


62


consume somewhat more fabric when compared with the seams


90


which join the outer layers


52


.




When the seams


90


and


92


are completed, the outwardly extending portions of the outer and inner layers


52


and


62


comprising the side wall assemblies


50


form stiffening panel receiving pockets


76


. Thus, the completed side wall


22


includes eight stiffening panel receiving pockets


76


, including the stiffening panel receiving pockets defined by the seams


72


and


74


of each side wall assembly


50


and the stiffening panel receiving pockets


76


which are formed when the seams


90


and


92


are completed.




Referring simultaneously to

FIGS. 1 and 4

, the bulk bag


20


includes an octagon shaped bottom wall


96


which is secured to the outer and inner layers


52


and


62


of the side wall assemblies


50


by the bottom seam


82


. Like the other components of the bulk bag


20


, the bottom wall


96


is preferably formed from polypropylene fabric. Other materials may be utilized in the construction of the bottom wall


96


and the other components of the bulk bag


20


depending upon the requirements of particular applications of the invention.




A pallet


98


may be employed to facilitate transportation and positioning of the bulk bag


20


and the contents thereof. In such instances, the bulk bag


20


is preferably provided with retaining members


100


which are extended around component parts of the pallet


98


to retain the bulk bag


20


in engagement therewith. Other mechanisms for securing the bulk bag


20


to the pallet


98


may be utilized in lieu of the retaining members


100


depending upon the requirements of particular applications of the invention.




The bulk bag


20


may be provided with a top or cover


102


. If used, the top or cover


102


is preferably formed from woven polypropylene fabric, it being understood that other materials can be utilized in the construction of the top


102


, if desired. The top


102


may be completely removable from the side wall


22


of the bulk bag


20


. Alternatively, the top


102


may be hingedly secured to the side wall


22


by means of the top seam


84


situated at the top of the side wall


22


.




The top


102


may comprise a cover panel


104


and a skirt


106


extending downwardly from the panel


104


. The top


102


can be flexible or rigid, in which event a stiffening panel


108


is used. Conventional retaining apparatus may be utilized to secure the top


102


to the side wall


22


of the bulk bag


20


, if desired.




In

FIG. 5

, there is shown a bulk bag


120


comprising a first variation of the bulk bag


20


illustrated in

FIGS. 1-4

, inclusive, and described hereandabove in conjunction therewith. Many of the component parts of the bulk bag


120


are identical in construction and function to component parts of the bulk bag


20


. Such identical component parts are designated in

FIG. 5

with the same reference numerals utilized above in the description of the bulk bag


20


.




Bulk bags constructed in accordance with the present invention may be provided with conventional gland-type liners which facilitate the use of the bulk bag to receive, transport, discharge, and store liquids. The liner extends around the entire interior of the bulk bag


120


including the interior of the side wall


22


, the bottom wall


96


, and the top wall


102


.




Bulk bags constructed in accordance with the present invention are adapted for use with a variety of discharge apparatus. The bulk bag


120


includes a discharge port


130


formed in one of the side wall portions comprising the side wall


22


, it being understood that the discharge port


130


can also be positioned in the bottom wall of the bulk bag


120


. The discharge port


130


extends through the side wall


22


and through the liner, thereby connecting the interior of the bulk bag


120


to the exterior thereof. Discharge ports of the type shown in

FIG. 5

are particularly adapted for use in bulk bags designed to receive, transport, store, and discharge liquids.





FIG. 6

comprises a horizontal sectional view taken through the upper portion of the bulk bag


120


of

FIG. 5

, it being understood that a similar horizontal section view taken through the upper portion of the bulk bag


20


of

FIG. 1

would be, in all practical respects, identical. In

FIG. 6

the eight stiffener panel receiving pockets


76


and the eight stiffener panels


80


received therein are illustrated.





FIGS. 7

,


8


, and


9


illustrate a bulk bag


140


comprising a second alternative version of the bulk bag


20


of FIG.


1


. Many of the component parts of the bulk bag


140


are identical in construction and function to component parts of the bulk bag


20


illustrated in FIG.


1


and to component parts of the bulk bag


120


illustrated in FIG.


5


. Such identical component parts are designated in

FIGS. 7

,


8


, and


9


with the same reference numerals utilized in the foregoing description of the bulk bags


20


and


120


.




The bulk bag


140


differs from the bulk bags


20


and


120


in that the bulk bag


140


is not mounted on a pallet. Rather, the bulk bag


140


is provided with lift loops


142


which are utilized in the transportation and positioning of the bulk bag


140


. The lift loops


142


are preferably formed from nylon webbing and are conventional in design and function.




The bulk bag


120


differs from the bulk bag


20


in that it is provided with a permanently installed top


122


which is secured to the side wall


22


by a seam


124


. As is conventional in bulk bag construction, the top


122


is provided with a fill spout


126


.




The bulk bag


140


further differs from the bulk bags


20


and


120


in that the bulk bag


140


is provided with a discharge port


144


formed in the bottom wall


96


. The discharge port


144


comprises four closure flaps


146


formed from the material of the bottom wall


96


and interconnected by a drawstring


148


. A liner


128


extends through the discharge port


144


and may be provided with closure apparatus such as a tie-tie


150


. Those skilled in the art will realize that the discharge port


144


is conventional in design and construction.




Referring to

FIG. 10

, one of the primary advantages derived from the use of the present invention comprises the fact that octagon shaped bulk bags constructed in accordance with the invention are readily adapted for stacking.

FIG. 10

illustrates the bulk bag


120


of

FIG. 5

, however, it will be understood that the bulk bag


20


of

FIG. 1

, the bulk bag


140


of

FIG. 7

, and in fact all bulk bags incorporated in the present invention are readily adapted for stacking.

FIG. 10

illustrates three bulk bags comprising the present invention stacked one on top of another, but in actual fact up to six bulk bags comprising the present invention can be stacked one on top of another depending on the density of the material contained in the bulk bags.




As is best shown in

FIG. 11

, bulk bags comprising the present invention are readily foldable for return shipment.

FIG. 11

illustrates a bulk bag


20


of the type shown in

FIG. 1

folded and positioned on the pallet


98


for return shipment, it being understood that the bulk bag


120


of

FIG. 5

, the bulk bag


140


of

FIG. 7

, and in fact all bulk bags incorporating the invention are adapted for folding in the manner illustrated in FIG.


11


.




Bulk bags comprising the present invention can be manufactured in a variety of sizes.

FIG. 12

illustrates a plurality of small size bulk bags


160


incorporating the present invention. The bulk bags


160


are octagonal in shape and are otherwise substantially identical to the bulk bags of

FIGS. 1-9

, inclusive. As is clearly shown in

FIG. 12

, a plurality of small size bulk bags


160


may be received on a single pallet


162


and secured by a strap


164


. The bulk bags


160


thus positioned and secured are adapted for stacking one on top of another. Up to six layers of bulk bags


160


may be stacked one on top of another depending upon the density of the material contained in the bulk bags.




The present invention further comprises a method of manufacturing octagon shaped bulk bags. In accordance with the method, there is provided eight substantially identical fabric sheets. The fabric sheets are preferably formed from woven polypropylene fabric, however, other fabric materials can be utilized in the practice of the invention. Each of the sheets is characterized by an upper edge, a lower edge, and opposed side edges.




The fabric sheets are arranged in four pairs, each pair comprising an inner layer and an outer layer. The upper, lower, and side edges of each pair are respectively aligned. The inner and outer layers comprising each pair are joined by seams extending parallel to the side edges which are spaced apart to define a side wall portion comprising a stiffening panel receiving pocket. The inner and outer layers comprising the four pairs are joined edge to edge to form four additional side wall portions, each comprising a stiffening panel receiving pocket.




The method further comprises the step of providing an octagonal shaped bottom wall. The bottom wall is preferably formed from woven polypropylene fabric, however, other materials can be used in the practice of the invention. The bottom wall is secured to the lower edges of the inner and outer layers of the side wall portions by a bottom seam which also closes the lower ends of the stiffening panel receiving pockets.




A stiffening panel is received in each stiffening panel receiving pocket. The stiffening panels preferably comprise corrugated plastic panels, however, other materials can be used in the manufacture of the stiffening panels. After the stiffening panels are installed, the upper ends of the stiffening panel receiving pockets are closed, either permanently or releaseably.




Transportation and positioning of the bulk bag and the contents thereof is facilitated either by mounting the bulk bag on a pallet or by providing the bulk bag with lift loops. The bulk bag may be provided with a top closure which may be either flexible or rigid and which may be either permanently or releaseably secured. Discharge ports may be provided either in the bottom wall or in one of the side wall portions of the bulk bag.




Although preferred embodiments of the invention have been illustrated in the accompanying drawings and described in the foregoing Detailed Description, it will be understood that the invention is not limited to the embodiments disclosed, but is capable of numerous rearrangements, modifications, and substitutions of parts and elements without departing from the spirit of the invention.



Claims
  • 1. An octagon shaped bulk bag comprising:eight double layer side wall portions disposed in an octagonal array and each comprising a stiffening panel receiving pocket; alternating double layer side wall portions each comprising two half side wall portions joined by stitching; eight stiffening panels each received in the stiffening panel receiving pocket comprising one of the side wall portions; means for retaining the stiffening panels in the stiffening panel receiving pockets; a bottom wall extending between and connected to the bottom of each of the side wall portions; each of the side wall portions being charaterized by: spaced apart vertically extending seams defining the width of the side wall portion; a bottom seam connecting the bottom wall to the side wall portion; and a top seam; the four seams defining the length and width of the side wall portion and comprising the means for securing the stiffening panel in the stiffening panel receiving pocket of the side wall portion; the eight side wall portions comprising the bulk bag being substantially equal in length and width; and the eight stiffening panels which are received in the stiffening panel receiving pockets of the side portions being substantially equal in length and width.
CROSS-REFERENCE TO RELATED APPLICATIONS

This is a continuation application under 37 C.F.R. §1.63 of application Ser. No. 09/515,631 filed Feb. 29, 2000, now U.S. Pat. No. 6,244,443, which is a continuation-in-part of application Ser. No. 09/458,362 filed Dec. 9, 1999, now U.S. Pat. No. 6,220,755, which is a continuation-in-part of application Ser. No. 09/390,403 filed Sep. 3, 1999, now U.S. Pat. No. 6,203,198.

US Referenced Citations (4)
Number Name Date Kind
4903859 Derby et al. Feb 1990 A
5323922 Lapoint, Jr. et al. Jun 1994 A
5829595 Brown et al. Nov 1998 A
6000549 Perkins Dec 1999 A
Continuations (1)
Number Date Country
Parent 09/515631 Feb 2000 US
Child 09/771270 US
Continuation in Parts (2)
Number Date Country
Parent 09/458362 Dec 1999 US
Child 09/515631 US
Parent 09/390403 Sep 1999 US
Child 09/458362 US