CA2299708A1

CA2299708A1 - Method and apparatus for packaging bulk bags

Info

Publication number: CA2299708A1
Application number: CA002299708A
Authority: CA
Inventors: Guy Fournier
Original assignee: Control and Metering Ltd
Current assignee: Individual
Priority date: 2000-02-29
Filing date: 2000-02-29
Publication date: 2001-08-29

Abstract

A method and apparatus for packaging empty bulk bags into a rigid container without significant release of powdered residue of bag contents being released into the work environment. The apparatus comprises a packing enclosure which closely receives an open-topped rigid container and which is provided with an access opening for inserting the rigid container and a resealable opening located above the top of the container through which empty bulk bags can be deposited. The apparatus further comprises a bag compression plate which is shaped and sized to be closely received inside the enclosure and inside the rigid container, and which can be lowered into the container to compress the bags therein. The metal plate is provided with an opening through which a negative pressure is applied to the interior of the enclosure, so that dust released during compression is extracted from the enclosure without being released into the working environment.

Description

METHOD AND APPARATUS FOR PACKAGING BULK BAGS
FIELD OF THE INVENTION
The present invention relates to container bags known as bulk bags or flexible intermediate bulk containers (FIBC's), and more particularly to a method and apparatus for packaging empty, used bulk bags into a sealed container for re-use or disposal.
BACKGROUND OF THE INVENTION
Bulk bags are increasingly employed in cargo handling and transporting situations, particularly for the handling of fine, cohesive, powdery bulk materials. Bulk bags are preferred by customers whose requirements for such materials fall between the extremes of bulk delivery and low volume paper sack delivery. Bulk bags typically have a volume of about 20 to 75 cubic feet, and typically comprise a single layer of woven polypropylene. These bags may also have an inner liner of sheet material, typically a polyolefin such as polyethylene.
Bulk bags typically have a closable filling opening which can also be used for ventilation during emptying, and the bottom is typically provided with a bag outlet which is tightened and tied with one or more cords or held in position with a clip.
During emptying of bulk bags, precautions are typically taken to minimize the release of the powdered contents of the bags into the working environment.
After the bulk bags are emptied, they are typically collected for re-use or disposal by packing them into other bags or rigid containers such as boxes. Although the emptied bulk bags can contain significant residual amounts of powdered materials, few precautions are typically taken to prevent the release of powdered materials into the work environment during the collection and packaging of the emptied bulk bags. The release of such materials, even in relatively small quantities, may be undesirable both from a health and safety standpoint, and due to the risk of contamination of other products.

One system known to the applicant for packaging of empty bulk bags is to pack the bags into an open-topped cardboard container, known as a "gaylord box", and to compress the bags within the box with a metal plate fitted with a vacuum port through which dust given off by the bags is withdrawn. While this system somewhat reduces the amount of dust released during packing the empty bulk bags, it does not provide a complete solution to the problem of dust release during handling of the emptied bulk bags.
SUMMARY OF THE INVENTION
The present invention overcomes the above-discussed problems of the prior art by providing a method and apparatus for packaging empty bulk bags into a rigid bag container which eliminates or significantly reduces the amounts of powdered materials released into the working environment during collection and packaging of empty bulk bags.
The apparatus of the present invention provides a packing enclosure in which a rigid bag container such as a gaylord box is received through an access opening. The packing enclosure has a resealable opening through which empty bags can be inserted into the open top of the rigid container.
The apparatus of the present invention is also provided with a bag compressor, which is preferably in the form of a metal plate or a heavy hollow lid which is initially positioned above the resealable opening through which the bags are inserted, and which is movable downwardly into the box to compress the empty bags.
Thus, the present invention provides a compact, relatively inexpensive apparatus which takes up substantially the same amount of floor space as a gaylord box, and which is effective to prevent the release of dust into the atmosphere during collection and packaging of empty bulk bags.

BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be described, by way of example only, with reference to the accompanying drawings, in which:
Figure 1 is a front elevation view of a preferred apparatus according to the present invention, with the bag compressing plate suspended above the packing enclosure;
Figure 2 is a side elevation view of the apparatus of Figure 1, also with the bag compressing plate suspended above the packing enclosure;
Figure 3 is a perspective view of the packing enclosure of Figure 1 and a gaylord box which may be used with the apparatus of Figure 1;
Figure 4 is a perspective view of the bag compressing plate of the apparatus of Figure 1;
Figure 5 is a cross-sectional side elevation view of the bag compressing plate taken along the line 5 - 5' in Figure 4; and Figures 6 to 9 are front elevation views illustrating a preferred method of use of the apparatus of Figure 1.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
A preferred apparatus and method according to the present invention is now described below with reference to the drawings. The following description relates to the packaging of bulk bags into a gaylord box. However, it will be appreciated that the principles of the present invention are applicable to the packaging of bulk bags into any rigid container.
The term "bulk bags" as used throughout this application is intended to include within its scope flexible intermediate bulk containers (FIBC's) and other flexible containers for handling powdered bulk materials. Such containers may also be referred to as "big bags", "supersacks", etc. The bulk bags packaged according to the present invention preferably have the capacities disclosed above, and typically measure about 35 inches wide by about 50 inches tall.
The dimensions of the apparatus 10 given below are for use in association with a substantially cubic gaylord box 24 having a height of about 40 inches, sides 28 having lengths of 44 and 48 inches, with a closed bottom 26, an open top 30, and a removable cover 32. For ease of reference, the longer sides of box 24 are referred to by reference number 28a and the shorter sides of box 24 are referred to by reference number 28b.
The gaylord box 24 is preferably constructed from cardboard or other rigid material.
The structure of a preferred apparatus 10 according to the invention will now be discussed below with reference to Figures 1 to 5.
Preferred apparatus 10 comprises a packing enclosure 12 and a bag compressing plate or "tamper" 14 having a dust extraction port 16. The packing enclosure 12 comprises an upper end 18, a lower end 20, and a plurality of vertically extending sides 22. As best seen in Figure 3, the packing enclosure 12 has four sides 22a, 22b, 22c and 22d to accommodate gaylord box 24.
A plurality of the sides 22 of the enclosure 12 are defined by vertically extending side walls 34. In the preferred embodiment shown in the drawings, the apparatus 10 has three side walls 34a, 34b and 34c (corresponding to sides 22a, 22b and 22c, respectively) which form a three-sided enclosure around the box 24. Side 22d of the enclosure 12 is preferably left open for reasons which will be discussed below. Side wall 34b preferably has a length (measured horizontally along the plane of plate 14) of about 52 inches and opposed side walls 34a and 34c preferably each have a length of about 48 inches. It will be appreciated that the dimensions of the apparatus 10 can be modified to accommodate rigid containers and bulk bags of varying sizes.

-S-Preferably, the size of the plate 14 and enclosure 12 are such that the apparatus can be used with gaylord boxes 24 of various dimensions. Therefore, the preferred dimensions of apparatus 10 given below include provide certain tolerances, or clearance, between the sides of box 24, the enclosure 12, and plate 14. It will be appreciated that one reason for these tolerances is to allow the apparatus to accomodate gaylord boxes 24 which are either larger or smaller than that described below.
The side walls 34 of enclosure 12 closely receive the sides 28 of the box 24 and extend upwardly beyond the open top 30 of the box 24, such that the box 24 is received inside the lower end 20 of the packing enclosure 12. Preferably, the packing enclosure has inside dimensions of about 48 by 52 inches, leaving about 2 inches clearance between the sides 28 of the box 24 and the side walls 34 of the enclosure 12.
In the preferred embodiment shown in the drawings, the gaylord box 24 has a height of about 40 inches and is supported on a wooden pallet 36 having a height of about 6 inches. The vertically extending side walls 34 of the packing enclosure 12 preferably extend to a height of about seven feet to allow sufficient clearance for insertion of bulk bags into the open top 30 of box 24.
The side walls 34 of the packing enclosure 12 are preferably constructed from a tubular steel frame covered by steel panels. The tubular frame members preferably have a square cross section and are connected to one another by welding or fasteners.
As shown in the drawings, the enclosure 12 may preferably be provided with feet which extend below the bottoms of the steel panels, the feet preferably being provided with outwardly extending flanges having apertures through which the feet can be mounted to a floor. In the preferred embodiment shown in the drawings, the rigidity of the three-walled packing enclosure 12 is increased by extending a metal spacer bar 38 across the top of the open side 22d of the enclosure 12.

At least one of the sides 22 of the packing enclosure 12 is provided with an access opening 40 for insertion and removal of the box 24. Preferably, the box 24 is horizontally slidable in and out of the packing enclosure 12, for example by the use of a fork-lift vehicle which engages the pallet 36 on which the box 24 is supported. In order to allow for easy insertion and removal of the box 24, the access opening 40 preferably extends across the entire open side 22d of the packing enclosure 12. Further, the access opening 40 preferably has a height which is sufficient to allow the box 24 and its associated pallet 36 to be inserted into the packing enclosure 12. In a particularly preferred embodiment of the invention, the height of the access opening 40 is about 40 to 46 inches.
A resealable opening is also provided in at least one of the sides 22 of the packing enclosure 12 through which bulk bags can be inserted into the box 24.
In the preferred embodiment shown in the drawings, the resealable opening is in the form of a dust curtain 42 provided in the open side 22d of the packing enclosure 12, directly above the access opening 40. Preferably, dust curtain 42 comprises of a plurality of overlapping sheets 44 of flexible, plastic material hanging from the spacer bar 38 and extending downwardly to approximately the top 30 of the box 24, and preferably extending somewhat below the top 30 of box 24. To allow sufficient room for insertion of bulk bags, the dust curtain 42 preferably extends across substantially the entire width of the open side 22d of packing enclosure 12.
The metal plate 14 used to compress the bags is shaped to be closely received by both the side walls 34 of the packing enclosure 12 and the sides 28 of box 24, and is sufficiently heavy that its weight causes the required amount of compression of bulk bags inside the box 24. In the preferred embodiment shown in the drawings, the bag compression plate 14 comprises a rectangular steel plate having a thickness of about 3/8 inches, and with two sides having a lengths of about 44 and two sides having a length of about 41 inches. The metal plate 14 is preferably suspended inside the packing enclosure 12 from a hoist 46 which is connected by cables 48 to metal hooks or apertured lugs 56, 58, 60 and 62 located at the four corners of plate 14.
Preferably, a one quarter inch thick punched metal plate 64 is attached to the outer perimeter of the metal plate 14 to increase its rigidity.
The metal plate 14 is provided with dust extraction port 16 which comprises an aperture 66 from which protrudes an upwardly extending nozzle 68. The nozzle may be attached to a flexible hose 70 or the like through which it is connected to a remotely located dust extraction apparatus 72, schematically illustrated in Figure 1 only.
As discussed above, the metal plate 14 is shaped and sized to be closely received inside the vertically extending side walls 34 of the packing enclosure 12 and inside the box 24. With the dimensions given above, there is approximately 3.5 inches clearance between the longer sides of the plate 14 and the side walls 34a and 34c of the enclosure 12, and approximately 4 inches clearance between the shorter sides of the plate 14 and side wall 34b or dust curtain 42.
To avoid excessive scraping between the metal plate 14 and the side walls 34 of the enclosure 12, and to assist in guiding metal plate 14 into box 24, the side walls 34a and 34c are preferably provided with guide members 50, 52, 54 and 55 positioned above the open top 30 of box 24. The guide members are preferably wedge shaped and are mounted at substantially the same height on opposed side walls 34a and 34c such that they taper downwardly toward the lower end 20 of the enclosure and inwardly toward one another and toward the middle of the enclosure 12. The guide members can be constructed of any suitable material, with durable rubber, plastic or metal being preferred.
Each guide member preferably has a width of about 8 inches, a length of about 16 inches, and protrudes inwardly of side wall 34 by a distance of about 3 to 3'/2 inches, such that the clearance between the guide members and the sides of metal plate 14 is gradually reduced as plate 14 is lowered into the open top 30 of box 24.

_$_ Preferably, as shown in Figure 7, the guide members 50 and 52 extend inwardly from respective side walls 34a and 34c by a sufficient distance such that a minimum distance D (shown in Figure 7) between guide members 50 and 52 is less than the length of sides 28b of box 24 which extend perpendicular to side walls 34a and 34c, and slightly greater than the length of the sides of plate 14 which extend perpendicular to side walls 34a and 34c. Therefore, the guide members act to guide the edges of plate 14 inwardly of the sides 28 of box 24.
In order not to interfere with insertion or removal of the box 24 from enclosure 12, the lower ends of the guide members are located about 6 inches above the top 30 of box 24. Preferably, as shown in the drawings, each side wall 34a and 34c is provided with two guide members spaced from one another by a distance of about inches.
During use of apparatus 10, the plate 14 is movable vertically between a first position A (Figure 6) in the upper end 18 of the enclosure 12 above the dust curtain 42 and a second position B (Figure 8) inside the box 24. Preferably, the second position B
is at or near the bottom 26 of box 24.
A method for packing empty bulk bags 74 into box 24 using apparatus 10 is now described below.
Firstly, the box 24 having its lid 32 removed is inserted into the packing enclosure 12, and is preferably supported on pallet 36. As shown in Figure 6, the steel plate 14 is suspended in the upper end 18 of the packing enclosure 12 at its initial position A, and the dust extraction apparatus 72 (shown in Figure 1 only) is activated to create a negative pressure inside the packing enclosure 12.
As shown in Figure 6, the plastic sheets 44 making up dust curtain 42 are pushed aside to allow empty bulk bags 74 to be dropped into the open top 30 of box 24. Preferably, dust generated by insertion of the bags 74 into box 24 is removed from the enclosure 12 by the dust extraction apparatus 72. Once the box becomes filled or nearly filled with empty bags 74, the steel plate 14 is lowered, guided by the guide members 50, 52, 54 and 55, toward the open top 30 of the box 24. As illustrated in Figure 7, there is little or no clearance between the edges of the plate 14 and the lower portions of the guide members 50, 52, 54 and 55. The plate 14 is therefore guided into the open top 30 of box 24. With the dimensions of the metal plate 14 and the box 24 given above, there is approximately 1 '/Z inches clearance between the long sides of the metal plate 14 and the long sides 28 of box 24, and approximately 2 inches of clearance between the shorter sides of the metal plate and the shorter sides 28 of box 24.
The metal plate 14 continues to be lowered until it reaches position B shown in Figure 8, thereby compressing the empty bags 74 inside the box 24. The air displaced by the compression of the bags 74 is removed from the enclosure 12 by the dust extraction apparatus 72 (shown in Figure 1 ). If, for example, the steel plate 14 is lowered by hoist 46 at a rate of about 16 feet per minute, the amount of air displaced by the plate 14 is approximately 256 cubic feet per minute. Therefore, the capacity of the dust extraction apparatus 72 is preferably matched to the size and rate of lowering of the plate 14.
After the bags 74 are compressed inside box 24, the dust extraction apparatus 72 is optionally deactivated and the steel plate 14 is lifted out of the box 24 to a position above the top 30 of the box 24, and preferably to its initial position A as shown in Figure 9.
Since the compressed bags 74 occupy less space than the uncompressed bags 74 which are dropped into the box 24, it may be preferred to place more bags 74 into the box 24 after the compressing operation described above. Therefore, the steps of lowering the plate 14 to compress the bags 74 and subsequently lifting the plate 14 to -1~-allow more bags 74 to be inserted are preferably repeated until such time as the box 24 is substantially filled with compressed bags 74. When the box 24 is full, the top 30 of box 24 is sealed with lid 32, and the box 24 is removed from the enclosure 12, preferably with the assistance of a fork-lift or the like.
While the invention has been described with reference to a specific preferred embodiment, it will be appreciated that numerous modifications can be made to the apparatus without departing from the spirit and scope of the invention. For example, although the metal plate 14 has been described as being lowered by a hoist to compress the bags with its weight, it will be appreciated that the plate 14 may be configured to exert a force on the bags which is greater than its own weight, for example where it is attached to a press which pushes the plate downwardly into the box 24.
Furthermore, it will be appreciated that the metal plate 14 does not necessarily form the top of the enclosure 12, but may rather be provided completely inside the enclosure12, to further prevent release of dust into the work environment.
Furthermore, it may be preferred in some embodiments of the invention to provide the edges of the plate with sealing means, for example strips of rubber, plastic or similar materials, which would form a seal against the walls of the enclosure and/or the sides of the box.
It will also be appreciated that the enclosure 12 is not necessarily provided with an open side as illustrated at 22d to provide access for the box 24. Rather, it may be preferred in some embodiments of the invention to provide the enclosure with one wall which can be removed or opened in the manner of a door or the like, and which could be closed after insertion of the box 24 to thereby provide an enclosure which is closed around all sides of the box.
Further, it will be appreciated that it is not necessary to provide the resealable opening and the access opening on the same side of the enclosure 12, nor is it necessary that the resealable opening be in the form of a dust curtain 42.
Rather, it may be preferred to provide resealable openings of various shapes and sizes through which empty bulk bags can be inserted, and to provide the resealable opening on any portion of the enclosure which is higher than the top of the box.
Lastly, it will be appreciated that the invention is not restricted to use with square or rectangular gaylord boxes, but may be adapted to rigid containers of any shape, including cylindrical containers.
Although the invention has been described in connection with certain preferred embodiments, it is not limited thereto. Rather, the invention includes within its scope all embodiments which may fall within the scope of the following claims.

Claims

1. An apparatus for packaging empty bulk bags into a rigid bag container having a closed bottom, closed sides and an open top, the apparatus comprising:
a packing enclosure to receive the bag container with its open top facing upwardly, the packing enclosure comprising an upper end, a lower end and a plurality of vertically extending sides, at least one of the sides of the enclosure being provided with an access opening for inserting and removing the bag container, at least one of the sides of the enclosure being provided with a resealable opening above the open top of the bag container through which the bags can be loaded into the bag container while it is received in the enclosure, and a plurality of the sides of the enclosure being defined by vertically extending side walls which closely receive the sides of the bag container and which extend upwardly beyond the open top of the bag container, such that the bag container is received inside the lower end of the packing enclosure;
bag compression means comprising a movable plate shaped and sized to be closely received inside the side walls of the packing enclosure and inside the bag container, the plate being being movable vertically between a first position in the upper end of the enclosure above the resealable opening to a second position inside the rigid bag container; and dust extraction means through which particulate matter is discharged from inside the packing enclosure, the dust extraction means comprising a dust extraction port in the movable plate.

2. The apparatus of claim 1, wherein the packing enclosure and the rigid bag container each have four sides.

3. The apparatus of claim 2, wherein three of the sides of the packing enclosure are defined by the vertically extending side walls.

4. The apparatus of claim 3, wherein a fourth side of the packing enclosure is provided with the access opening for insertion and removal of the bag container.

5. The apparatus of claim 4, wherein the access opening has a width sufficient to allow the bag container to be slid horizontally into and out of the packing enclosure.

6. The apparatus of claim 4, wherein the fourth side of the packing enclosure is provided with the resealable opening.

7. The apparatus of claim 5, wherein the resealable opening comprises a plastic curtain which extends horizontally across the fourth side of the box and extends vertically downwardly from below the first position of the movable plate at least to the top of the bag container.

8. The apparatus of claim 4, wherein two of said vertically extending side walls are in opposed facing relationship to one another, and wherein said two opposed side walls are provided with wedge shaped guide members located above the access opening, said guide members tapering inwardly toward one another and downwardly toward the lower end of the packing enclosure, such that a minimum distance between any two of said guide members positioned on respective ones of said two opposed side walls, measured in a plane of the movable plate, is slightly greater than a length of the movable plate and less than a length of the bag container, wherein said length of the movable plate and said length of the bag container are measured in a direction perpendicular to said two opposed side walls when said bag container and said movable plate are inside said packing enclosure.

9. The apparatus of claim 1, wherein the movable plate is comprised of metal and is sufficiently heavy such that its weight causes sufficient compression of the bulk bags inside the bag container.

10. A method for packing empty bulk bags, comprising:
(a) providing an apparatus comprising a packing enclosure having an upper end, a lower end and a plurality of vertically extending sides, a plurality of the sides of the enclosure being defined by vertically extending side walls; a bag compression means comprising a vertically movable plate shaped and sized to be closely received inside the side walls of the packing enclosure; and a dust extraction means to discharge particulate matter from inside the packing enclosure, the dust extraction means including a dust extraction port in the movable plate;
(b) providing a rigid bag container having a closed bottom, closed sides and an open top, the bag container being sized and shaped to be closely received by the vertically extending side walls in the lower end of the packing enclosure, such that its open top is positioned below the resealable opening in the packing enclosure;
(c) horizontally sliding the bag container into the packing enclosure through the access opening until the bag container is completely received in the lower end of the packing enclosure;
(d) activating the dust extraction means to create a negative pressure inside the packing enclosure;
(e) with the movable plate at an initial position above the resealable opening, inserting one or more of the empty bulk bags through the resealable opening into the open top of the bag container;

(f) lowering the movable plate, along the vertically extending side walls of the packing enclosure, into the open top of the bag container a sufficient distance to compress the empty bulk bags inside the container, and removing particulate matter during compression of the bags through the dust extraction port in the movable plate;
(g) lifting the movable plate out of the bag container and to the initial position above the resealable opening;
(h) sealing the top of the bag container; and (i) horizontally sliding the bag container out of the packing enclosure.

11. The method of claim 10, wherein steps (e), (f) and (g) are repeated until the bag container is substantially filled with the bulk bags in a compressed state.