Corrugated pallet

Abstract

A corrugated pallet produced from two flat blanks is provided. The pallet may include a pallet top, a pallet bottom, and a plurality of corner straps locking the pallet top to the pallet bottom. Each of the pallet top and the pallet bottom may include folded portions, the folded portions of the pallet top interlocking with the folded portions of the pallet bottom when the pallet top and the pallet bottom are assembled to each other in nested relation. The pallet top may define a top surface of the pallet. The pallet bottom may define a bottom surface of the pallet. The corner straps may lock into one or both of the pallet top and the pallet bottom from the top or bottom surfaces of the pallet.

Claims

1. A corrugated pallet produced from two flat blanks, the pallet comprising: a pallet top and a pallet bottom, each of the pallet top and the pallet bottom comprising folded portions, the folded portions of the pallet top assembled to the folded portions of the pallet bottom in nested relation when the pallet top and the pallet bottom are assembled to each other, the pallet top defining a top surface of the pallet, the pallet bottom defining a bottom surface of the pallet; and a plurality of corner straps locking the pallet top to the pallet bottom, the corner straps folded into contact with an exterior surface of the pallet to lock into one or both of the pallet top and the pallet bottom.

2. The corrugated pallet of claim 1, wherein each corner strap extends from a blank surface opposing the outer surface to which the corner strap attaches.

3. The corrugated pallet of claim 1, wherein each corner strap is folded into contact with the bottom surface of the pallet.

4. The corrugated pallet of claim 1, wherein each corner strap is folded into contact with the top surface of the pallet.

5. The corrugated pallet of claim 1, wherein: at least one of the corner straps is folded into contact with the bottom surface of the pallet; and at least another of the corner straps is folded into contact with the top surface of the pallet.

6. The corrugated pallet of claim 1, wherein a portion of each corner strap is received within a corresponding slot defined within the top surface of the pallet top or the bottom surface of the pallet bottom.

7. The corrugated pallet of claim 1, wherein each corner strap is formed integrally with the pallet top or pallet bottom.

8. The corrugated pallet of claim 1, wherein: each blank is folded to produce only two vertically extending ribs, three horizontal panels, two vertical sidewalls, and two horizontal flaps; the ribs of the pallet top and the ribs of the pallet bottom lock each other from opening in the center of the pallet via a nested relationship; and the horizontal flaps lock the ribs from opening at the edges of the pallet via a nested relationship.

9. The corrugated pallet of claim 8, wherein the vertical sidewalls of at least one of the pallet top or the pallet bottom comprise vertical flaps that open inward to define fork passages.

10. The corrugated pallet of claim 9, wherein the vertical flaps lock the horizontal flaps from opening.

11. The corrugated pallet of claim 9, wherein each of the vertical sidewalls comprises vertical flaps that open inward to define fork passages.

12. The corrugated pallet of claim 8, wherein the ribs are discontinuous along their respective lengths.

13. The corrugated pallet of claim 8, wherein: the ribs of the pallet top and the pallet bottom lock each other from opening by intersecting perpendicularly with notches; and the horizontal flaps lock the ribs from opening by intersecting perpendicularly with notches.

14. The corrugated pallet of claim 8, wherein each of the vertical sidewalls transitions at an edge of a horizontal panel to extend between the top surface and the bottom surface to define a portion of an exterior perimeter of the pallet.

15. The corrugated pallet of claim 14, wherein the horizontal flaps extend inwards towards a center of the pallet directly from a terminal edge of the vertical sidewalls.

16. The corrugated pallet of claim 8, wherein: adjacent panels of the three horizontal panels of the pallet top and the pallet bottom abut each other without overlapping; and the ribs are locked without the use of adhesive.

17. A corrugated pallet produced from two flat blanks, the pallet comprising: a pallet top and a pallet bottom, each of the pallet top and the pallet bottom comprising folded portions, the folded portions of the pallet top assembled to the folded portions of the pallet bottom in nested relation, the pallet top and the pallet bottom each folded to define a horizontal panel; and a plurality of corner straps locking the pallet top and pallet bottom together, each corner strap at least partially overlapping portions of the horizontal panels to lock into outer surfaces of the pallet.

18. The corrugated pallet of claim 17, wherein at least one of the corner straps locks into a bottom surface of the pallet.

19. The corrugated pallet of claim 17, wherein at least one of the corner straps locks into a top surface of the pallet.

20. The corrugated pallet of claim 17, wherein each corner strap extends from a blank surface opposing the outer surface to which the corner strap attaches.

21. A corrugated pallet produced from two flat blanks, the pallet comprising: a pallet top and a pallet bottom, each of the pallet top and the pallet bottom comprising folded portions, the folded portions of the pallet top interlocking with the folded portions of the pallet bottom when the pallet top and the pallet bottom are assembled to each other in nested relation, the pallet top defining a top surface of the pallet, the pallet bottom defining a bottom surface of the pallet; and a plurality of corner straps locking the pallet top to the pallet bottom, the corner straps locking into one or both of the pallet top and the pallet bottom from the top or bottom surfaces of the pallet; wherein: each blank is folded to produce only two vertically extending ribs, three horizontal panels, two vertical sidewalls, and two horizontal flaps; the ribs of the pallet top and the ribs of the pallet bottom lock each other from opening in the center of the pallet via a nested relationship; and the horizontal flaps lock the ribs from opening at the edges of the pallet via a nested relationship.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The present disclosure and its many advantages and features will become better understood upon reading the following detailed description of the preferred embodiments in conjunction with the following drawings, wherein:

(2) FIG. 1 is a schematic drawing of a corrugated paperboard pallet in accordance with the present disclosure.

(3) FIG. 2 is a schematic drawing of the pallet of FIG. 1 in partially folded but unassembled state, in accordance with the present disclosure.

(4) FIG. 3 is a schematic drawing of the pallet of FIG. 1 prior to assembly in flat blanks state in accordance with the present disclosure.

(5) FIG. 4 is a schematic drawing of the pallet bottom of the pallet of FIG. 1 in the assembly process with ribs folded up in accordance with the present disclosure.

(6) FIG. 5 is a schematic drawing of the pallet top of the pallet of FIG. 1 in the assembly process with ribs folded down in accordance with the present disclosure.

(7) FIG. 6 is a schematic drawing of the pallet bottom and pallet top of the pallet of FIG. 1 in the assembly process aligned prior to compression together in accordance with the present disclosure.

(8) FIG. 6A is a cut-away perspective view of one end of the pallet of FIG. 1, showing how the horizontal flap is tucked under the top sheet, with slots engaging the ribs to hold them closed and to hold the top and bottom panels together.

(9) FIG. 7 is a schematic drawing of the pallet bottom and pallet top of the pallet of FIG. 1 in the assembly process after being compressed together in accordance with the present disclosure.

(10) FIG. 7A is a cut-away perspective view of the pallet of FIG. 1, showing the interengagement of the intersecting ribs in the central area of the pallet.

(11) FIG. 8 is a schematic drawing of the pallet of FIG. 1 in the assembly process after the horizontal flaps have been inserted in accordance with the present disclosure.

(12) FIG. 9 is a schematic drawing of the pallet of FIG. 1 in the assembly process after the fork passages are folded open in accordance with the present disclosure.

(13) FIG. 10 is a schematic drawing of the pallet of FIG. 1 in the assembly process after the top and bottom locking straps are folded over in accordance with the present disclosure.

(14) FIG. 11 is a schematic drawing of the pallet bottom of the pallet of FIG. 1 marked showing the corrugation directions with respect to rib direction, in accordance with the present disclosure.

(15) FIG. 12 is a comparison of the corrugated paperboard use per pallet between the prior art and the present disclosure.

(16) FIG. 13 is a comparison of the pallet shipping per truckload between the prior art and the present disclosure.

(17) FIG. 14 is a comparison of the relative pallet torsional stiffness between the prior art and the present disclosure.

DETAILED DESCRIPTION

(18) Turning to the drawings, wherein like reference characters designate identical or corresponding parts, FIG. 1 shows a corrugated paperboard pallet 30 in accordance with the present disclosure. The pallet 30 has fork passages 31, 32 for lifting and moving the pallet 30 when loaded with shipping goods. The pallet 30 is comprised of a pallet bottom 50 and a pallet top 70 that are comprised of sheets of corrugated paperboard.

(19) A schematic drawing of the pallet 30 of FIG. 1 in partially folded but unassembled state, in accordance with the present disclosure is shown in FIG. 2. The corrugated paperboard pallet 30 is produced from two flat blanks which comprise a pallet top 70 and a pallet bottom 50. The blanks 70, 50 are each folded to produce only two parallel vertically extending double thickness discontinuous ribs 71 and 51, three horizontal panels 40 and 45, two vertical sidewalls 41, 42, 46, 47 and two horizontal flaps 43, 44, 48, 49. The ribs 71 of the pallet top 70 and the ribs 51 of the pallet bottom 50 each have a central portion and two rib ends. The central portions of the ribs 51 and 71 lock each other from opening in the center of the pallet 30 by intersecting perpendicularly with notches 53, as shown in FIG. 7A. As shown in FIG. 6A, when completely assembled, the horizontal flaps 43, 44, 48, 49 lock the end portions of the ribs 71, 51 from opening at the edges of the pallet 30 by intersecting perpendicularly with notches 57, 58, 75, 55, 77. The vertical sidewalls 41, 42, 46, 47, once assembled, have vertical flaps 59, 79 that open inward defining fork passages whereby the vertical flaps lock horizontal flaps 43, 44, 48, 49 from opening.

(20) A schematic drawing of the pallet 30 of FIG. 1 prior to assembly in flat blanks state in accordance with the present disclosure is shown in FIG. 3. The pallet 30 is produced from two flat, die cut corrugated paperboard blanks that produce the pallet top 70 and pallet bottom 50. To facilitate shipping, it is preferable that the blanks 50, 70 be shipped flat to the shipper site such that more blanks can fill a truckload.

(21) The pallet bottom 50 of the pallet 30 of FIG. 1 is shown in the assembly process with ribs folded up in FIG. 4. The pallet bottom 50 is folded to produce only two vertically extending double thickness discontinuous ribs 51 near the longitudinal center, three horizontal panels 45, two sidewalls 46, 47 that will be vertical in the assembled pallet and two horizontal flaps 48, 49.

(22) The pallet top 70 of the pallet 30 of FIG. 1 is shown in the assembly process in FIG. 5 with ribs 71 folded down. The pallet top 70 is folded to produce only two vertically extending double thickness discontinuous ribs 71 near the longitudinal center, three horizontal panels 40, two sidewalls 41, 42 that will be vertical in the assembled pallet and two horizontal flaps 43, 44.

(23) A schematic drawing of the pallet bottom 50 and pallet top 70 of the pallet 30 of FIG. 1 in the assembly process aligned prior to compression together in accordance with the present disclosure is shown in FIG. 6. The pallet 30 is assembled by rotating the pallet top 70 and pallet bottom 50 to be perpendicular with each other and aligned such that ribs 71, 51 cross and nest in notches 53, as illustrated in FIG. 7A. The pallet bottom 50 has openings 54 for pallet jack wheels, should a pallet jack be used to lift and move the finished pallet 30. The ribs 51, 71 are preferably locked without the use of adhesive. The ribs 51, 71 may be mechanically locked during the intermediate step before assembly of the pallet top 70 with the pallet bottom 50, through the use of rib punch locks 52. However, for simplicity and strength, preferably no rib punch locks are utilized and ribs 51, 71 are locked closed by each other in the center when assembled together using notches 53. The end portions of the ribs 51, 71 are later locked by notches 57, 58 with 75, 76 and with 77, 78 with 56, 56.

(24) One end of the pallet 30 of FIG. 1, shown in FIG. 6A, illustrates how the horizontal flap 48 of the pallet bottom 50 is tucked under the pallet top 70, with notches 57 engaging the top of the ribs 71 to hold them closed and to lock the top and bottom panels against separating. We have found it to be desirable that the pallet 30 be designed so that it maintains integrity throughout shipping and handling vibration and loading conditions. We have found that one way to accomplish this goal is to design the pallet 30 using multiple series locks. For example, the top blank ribs 71 are locked from opening by the bottom blank ribs 51. The top blank horizontal flaps 43, 44 lock the bottom blank ribs 51 from opening. The top blank vertical flaps 79 lock the top blank horizontal flaps 43, 44 from opening. In one embodiment, corner straps 91, 92 lock (e.g., clamp) the pallet top 70 and pallet bottom 50 together, thereby locking the top blank vertical 79 flaps from opening. For example, as described more fully below, the corner straps 91, 92 may be folded into contact with the outer surfaces of the pallet 30. In one embodiment, the corner straps 91 may be folded into contact with the top surface of the pallet 30. Additionally or alternatively, the corner straps 92 may be folded into contact with the bottom surface of the pallet 30. The corner straps 91, 92 may be formed integrally with the pallet bottom 50 and pallet top 70, respectively, as shown in FIG. 8, for instance.

(25) Once aligned, the pallet top 70 and pallet bottom 50 are compressed together. A schematic drawing of the pallet bottom 50 and pallet top 70 of the pallet 30 of FIG. 1 in the assembly process after being compressed together in accordance with the present disclosure is shown in FIG. 7. The pallet 30, in compressed stated, is shown in FIG. 7. Horizontal flaps 48, 49, are ready to be folded to engage the notches 57, 58 with the notches 75 on the rib ends of the ribs 71 to lock the edges of ribs 71 closed, and the horizontal flaps 43, 44 are ready to be folded to engage the notches 77, 78 with the notches 55, 56 on the rib ends of the ribs 51 to lock the edges of ribs 51 closed.

(26) A schematic drawing of the pallet 30 of FIG. 1 in the assembly process after the horizontal flaps have been inserted in accordance with the present disclosure is shown in FIG. 8. The pallet 30 has the pallet top 70 and pallet bottom 50 locked together by the sidewalls 41 and 46 being folded vertical and horizontal flaps 43, 48 locking the edges of the end portions of the ribs 71, 51. The corner straps 91, 92 of the horizontal flaps 43, 48 are not assembled yet and will later be locked to the pallet top 70 and pallet bottom 50 through slots 93. Vertical flaps 59, 79 on the sidewalls 41, 46 are ready to be assembled.

(27) A schematic drawing of the pallet 30 of FIG. 1 in the assembly process after the fork passages are folded open in accordance with the present disclosure is shown in FIG. 9. The pallet 30 has pallet top 70 locked together with pallet bottom 50. The sidewalls 42, 46 are vertical as the horizontal flaps 43, 48 are locking the edges of the ribs 51, 71. Vertical flaps 59, 79 are folded inward defining fork passages 31, 32. The vertical flaps 59, 79 also thereby lock the horizontal flaps 43, 49 from opening.

(28) The final assembly step is locking the corners of the pallet 30. A schematic drawing of the pallet 30 of FIG. 1 in the assembly process after the top and bottom locking straps are folded over in accordance with the present disclosure is shown in FIG. 10. The pallet 30 is completed with pallet top 70 assembled together with pallet bottom 50. The corner straps 91, 92 of the horizontal flaps 42, 46 overlap the pallet top 70 and/or the pallet bottom 50 and lock into the pallet top 70 and/or the pallet bottom 50 from the top and/or bottom surfaces of the pallet 30, respectively. In one embodiment, the corner straps 91, 92 lock into slots 93, 94. As shown, each corner strap 91, 92 extends from a blank surface opposing the outer surface to which the corner strap 91, 92 attaches. For example, the corner straps 91 may extend from the pallet bottom 50, such as from the bottom surface of the pallet bottom 50, to then lock into or attach to the top surface of the pallet top 70. Additionally or alternatively, the corner straps 92 may extend from the pallet top 70, such as from the top surface of the pallet top 70, to then lock into or attach to the bottom surface of the pallet bottom 50.

(29) Corrugated paperboard is constructed with two directions: machine direction which is the direction it is pulled during fabrication and cross machine direction which is perpendicular to it, and is the axial direction of the flutes inside the corrugated paperboard. A schematic drawing of the pallet bottom 50 of the pallet 30 of FIG. 1 marked showing the corrugation material directions with respect to rib direction, in accordance with the present disclosure is shown in FIG. 11. In order to provide maximum load capacity for the pallet 30 and transfer of load between the pallet top 70 and pallet bottom 50, the cross machine direction 102 is preferably perpendicular to the rib direction 100.

(30) Although many corrugated pallets are designed using a high amount of corrugated paperboard, the present disclosure even provides substantial savings compared to lighter two-piece type corrugated pallets. A comparison of the corrugated paperboard use per pallet between the prior art two piece pallet and the present disclosure is shown in FIG. 12. The corrugated paperboard use per pallet is shown with a prior art four-rib per blank pallet 121 using 56 sq-ft compared to a 20% reduction for the present disclosure 122 at 45 sq-ft. This directly translates to a 20% reduction in raw material costs.

(31) One of the most significant benefits of the present disclosure is that the blanks can be shipped flat and be easily assembled on site at a shipper, compared to prior art corrugated pallets that must be preassembled at an outside plant due to complexity. This greatly increases the number of pallets that can be shipped per truckload. The blanks may also be shipped directly from a corrugator or sheet plant to a product shipper without secondary transportation and logistics. A bar chart shown in FIG. 13 shows a comparison of the pallet shipping per truckload between the prior art and the present disclosure. The pallet shipping per truckload for prior art preassembled pallets 131 is roughly 600 pallets. The pallet shipping per truckload with the present disclosure 132 is 2160. This ability directly translates to lower shipping and handling costs from both more pallets per truckload and from preferably only shipping blanks directly to the product shipper.

(32) Besides the cost savings, the present disclosure also provides a stronger and stiffer pallet with increased reliability. A bar chart shown in FIG. 14 shows a comparison of the relative pallet torsional stiffness between the prior art and the present disclosure. The relative pallet torsional stiffness is increased by about 85% according to the present disclosure in comparison with a prior art two-piece pallet without corner straps 141. During vibration as well as lifting of highly unbalanced loads, the pallet 30 according to the present disclosure is much more likely to perform without failure or separation of the pallet top 70 and pallet bottom 50.

(33) All relative and directional references (including: upper, lower, upward, downward, left, right, leftward, rightward, top, bottom, side, above, below, front, middle, back, vertical, horizontal, and so forth) are given by way of example to aid the reader's understanding of the particular embodiments described herein. They should not be read to be requirements or limitations, particularly as to the position, orientation, or use unless specifically set forth in the claims. Connection references (e.g., attached, coupled, connected, joined, and the like) are to be construed broadly and may include intermediate members between a connection of elements and relative movement between elements. As such, connection references do not necessarily infer that two elements are directly connected and in fixed relation to each other, unless specifically set forth in the claims.

(34) It will be further understood by those skilled in the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases at least one and one or more to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles a or an limits any particular claim containing such introduced claim recitation to examples containing only one such recitation, even when the same claim includes the introductory phrases one or more or at least one and indefinite articles such as a or an (e.g., a and/or an should be interpreted to mean at least one or one or more); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should be interpreted to mean at least the recited number (e.g., the bare recitation of two recitations, without other modifiers, means at least two recitations, or two or more recitations).

(35) While various aspects and examples have been disclosed herein, numerous modifications and variations of the described preferred embodiment will be apparent to those skilled in the art. Accordingly, the various aspects and examples disclosed herein are for illustration purposes and are not intended to be limiting, with the true scope and spirit being indicated by the following claims.