Pallet formed from molded fibrous panel material
A pallet is constructed of a molded fibrous panel material comprising a sheet portion defining opposite planar surfaces, and a grid of intersecting ribs projecting from one of the planar surfaces of the sheet portion, the sheet portion and ribs being integrally molded from fibrous material. The pallet comprises a horizontal portion of the molded fibrous panel material forming an upper support surface of the pallet, and at least two spaced runners joined to the horizontal portion for engaging the ground to space the horizontal portion above the ground. Each runner comprises at least two vertical portions of the molded fibrous panel material arranged in parallel relation and bonded to one another. In one embodiment, a single panel member is folded along a series of parallel fold lines extending across a width of the member, so as to form the runners and the horizontal portion from the single member.
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The invention relates to pallets for supporting items during shipment and storage. In particular, the invention relates to a pallet formed predominately from fibrous material.
BACKGROUND OF THE INVENTIONPallets traditionally have been manufactured of wood. The drawbacks associated with wooden pallets are well known, as noted for example in U.S. Pat. No. 5,184,558, incorporated herein by reference. Briefly, such drawbacks include heaviness, which makes the pallets cumbersome to handle and costly to ship, relatively great expense because of the costliness of wood, and difficulty and expense of disposing of the pallets when their useful life has been expended.
Because of such problems, various types of non-wooden pallets have been proposed. Some of these pallets are based on corrugated paperboard materials; others are based on honeycomb sandwich types of sheet materials. Still others are one-piece structures molded from fibrous material.
Pallets based on corrugated paperboard materials suffer from relatively poor rigidity because corrugated paperboard material by its nature is weak in bending parallel to the running direction of the flutes. Attempts have been made to improve rigidity in all directions by forming laminations of multiple layers of corrugated paperboard with the flutes in successive layers being oriented orthogonally. There is thus a need for a substantial number of separate pieces of corrugated sheet material, each die cut to appropriate size and shape, the pieces then being glued together. Thus, production and assembly of a pallet from such materials is relatively complex and expensive.
Pallets formed from honeycomb sandwich materials likewise tend to consist of a substantial number of separate pieces, and hence are relatively complex and expensive to produce and assemble. Additionally, the bond between the honeycomb cells and the face sheets represents a weak link in honeycomb sandwich structures; if this bond should break, the structure loses a great deal of its bending stiffness. In honeycomb sandwich panels based on paper, furthermore, exposure of the panels to water or other liquids can substantially weaken the panels.
With regard to one-piece molded fibrous pallets, a significant drawback is the need for a differently configured mold for each different pallet size or configuration to be produced.
SUMMARY OF THE INVENTIONThe invention addresses the above needs and achieves other advantages, by providing a pallet formed of molded fibrous panel material of a special type having substantial strength and relatively light weight. The pallet can be constructed from a small number of separate pieces of the panel material, or even from a single piece of the panel material.
More particularly, in accordance with the invention, a pallet is constructed of a molded fibrous panel material comprising a sheet portion defining opposite planar surfaces, and a grid of intersecting ribs projecting from one of the planar surfaces of the sheet portion, the sheet portion and ribs being integrally molded in one piece from fibrous material. The fibrous material can be, for example, recycled paper fibers. If water-resistance is required, the molded fibrous panel material can be impregnated with a suitable resin. The panel has substantial rigidity and integrity by virtue of its one-piece construction and the grid of intersecting ribs.
A pallet in accordance with the invention comprises a horizontal portion of the molded fibrous panel material forming an upper support surface of the pallet, and at least two spaced runners joined to and extending downward from the horizontal portion for engaging the ground to space the horizontal portion above the ground. Each runner comprises at least two vertical portions of the molded fibrous panel material arranged in parallel relation and bonded to one another.
In one embodiment, a single panel member is folded along a series of parallel fold lines extending across a width of the member, so as to form the runners and the horizontal portion from the single member. Because of the substantial rigidity of the panel, the grooves are formed in the panel to create the fold lines. The grooves represent regions in which fibrous material that would otherwise be there is missing or removed. The grooves preferably are generally V-shaped with a 90-degree included angle between opposite side walls of the grooves so that the panel can be folded 90 degrees about the fold line. The grooves either can be molded into the panel when it is molded, or alternatively can be formed by mechanically removing material (e.g., by routing) from the panel after it is formed.
In another embodiment, a top panel is affixed atop the horizontal portion of the pallet, such as by gluing. The top panel gives added strength to the pallet and also presents a smooth top surface. The top panel in one embodiment comprises a laminated multi-layer sheet, for example formed from paperboard sheets. Alternatively, the top panel can be another piece of the molded fibrous panel material, with the ribs facing downward toward the horizontal portion of the pallet. The ribs of the top panel can be bonded to the ribs of the horizontal portion, optionally with an intervening piece of sheet material (e.g., paperboard or the like) disposed therebetween.
The molded fibrous panel material forming the horizontal and vertical portions of the pallet can comprise a single layer of the molded fibrous panel material, such that one side of the panel is planar and the other side has exposed ribs. Alternatively, the panel material can comprise a double layer wherein the two layers are joined rib-to-rib, for added rigidity.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)Having thus described the invention in general terms, reference will now be made to the accompanying drawings, which are not necessarily drawn to scale, and wherein:
The present inventions now will be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all embodiments of the invention are shown. Indeed, these inventions may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Like numbers refer to like elements throughout.
The panel 20 advantageously can have a thickness ranging from about ¼-inch to about ¾-inch or more. The panel can be formed from recycled paper fibers. The panel can be impregnated with a resin to render it water-resistant, if desired. An advantage of the panel over the prior art is its relatively large strength-to-weight ratio, which makes possible the construction of pallets of relatively light weight but substantial strength.
The formation of the runner 32 is depicted in
Because the panel 20 has substantial bending stiffness as a result of the ribs 28, it is not possible to fold the panel without substantial breakage of fibers and buckling of the panel along the fold, and accordingly it is necessary to provide a groove or channel along each of the desired lines about which the panel is to be folded, as shown in
The V-shaped grooves can be formed in various ways. In one embodiment, the grooves are formed during the molding process, by suitably configuring the mold. Alternatively, the panel can be molded without grooves, and then the panel can be routed, machined, or otherwise mechanically operated upon to remove material to form the grooves.
To form the runner 32, the panel sections 20a and 20b are folded as a unit 90 degrees clockwise about the fold line B as shown in
A third embodiment of the invention is depicted in
A fifth embodiment of the invention is illustrated in
Finally, a sixth embodiment of the invention is shown in
Many modifications and other embodiments of the inventions set forth herein will come to mind to one skilled in the art to which these inventions pertain having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that the inventions are not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.
Claims
1. A pallet formed predominately of molded fibrous material, comprising:
- a molded fibrous panel material comprising a sheet portion defining opposite planar surfaces, and a grid of intersecting ribs projecting from one of the planar surfaces of the sheet portion, the sheet portion and ribs being integrally molded in one piece from fibrous material;
- a horizontal portion of said molded fibrous panel material forming an upper support surface of the pallet;
- the pallet further comprising at least two spaced runners joined to and extending downward from the horizontal portion for engaging the ground to space the horizontal portion above the ground, each runner comprising at least two vertical portions of the molded fibrous panel material arranged in parallel relation and bonded to one another.
2. The pallet of claim 1, wherein each runner includes a separate stiffening member disposed between and bonded to two of the vertical portions.
3. The pallet of claim 1, wherein the horizontal portion and the vertical portions are all integrally and serially joined together along a series of spaced parallel fold lines in the molded fibrous panel material.
4. The pallet of claim 3, wherein each fold line comprises a groove in the molded fibrous panel material.
5. The pallet of claim 4, wherein the grooves are molded into the molded fibrous panel material.
6. The pallet of claim 4, wherein the grooves are formed by mechanically removing fibrous material from the molded fibrous panel material.
7. The pallet of claim 4, wherein at least some of the grooves are generally V-shaped with an included angle of about 90 degrees between opposite side walls of the groove.
8. The pallet of claim 1, further comprising a top panel affixed atop the horizontal portion.
9. The pallet of claim 8, wherein the top panel comprises a multi-ply laminated material.
10. The pallet of claim 9, wherein the laminated material comprises paperboard.
11. The pallet of claim 8, wherein the top panel comprises another piece of the molded fibrous panel material.
12. The pallet of claim 11, wherein the ribs of the top panel face downward and the ribs of the horizontal portion face upward to oppose the ribs of the top panel.
13. The pallet of claim 12, wherein the ribs of the top panel are bonded directly to the ribs of the horizontal portion.
14. The pallet of claim 12, wherein the ribs of the top panel are joined to the ribs of the horizontal portion via an intervening piece of sheet material disposed therebetween, said sheet material being bonded to the ribs of the top panel and horizontal portion.
15. The pallet of claim 3, wherein the molded fibrous panel material forming the horizontal and vertical portions comprises a single layer of the molded fibrous panel material.
16. The pallet of claim 3, molded fibrous panel material forming the horizontal and vertical portions comprises two layers of the molded fibrous panel material joined rib-to-rib.
17. The pallet of claim 3, further comprising a reinforcing web bonded to one side of the molded fibrous panel material along at least one of the fold lines.
18. The pallet of claim 17, wherein the reinforcing web comprises a pressure-sensitive adhesive tape.
19. The pallet of claim 3, wherein the molded fibrous panel material has, in order, from one end to an opposite end of the molded fibrous panel material:
- first, second, and third fold lines for forming a first runner;
- fourth, fifth, sixth, and seventh fold lines for forming a second runner; and
- eighth, ninth, and tenth fold lines for forming a third runner.
20. The pallet of claim 1, wherein the molded fibrous panel material is formed from recycled paper fibers.
21. The pallet of claim 20, wherein the molded fibrous panel material is impregnated with a resin for rendering the molded fibrous panel material substantially water-resistant.
22. The pallet of claim 1, wherein each runner comprises a first pair of layers of the molded fibrous panel material joined rib-to-rib.
23. The pallet of claim 22, wherein each runner comprises a second pair of layers of the molded fibrous panel material joined rib-to-rib and joined to the first pair such that the runner comprises four layers.
24. The pallet of claim 22, wherein the horizontal portion comprises a separate piece of the molded fibrous panel material joined to the runners.
Type: Application
Filed: Mar 3, 2004
Publication Date: Sep 8, 2005
Applicant:
Inventors: Jimmy Cassidy (Hartsville, SC), Don Jenkins (Columbia, SC), Lawrence Renck (Hartsville, SC)
Application Number: 10/792,629