WO2004069671A1

WO2004069671A1 - Recyclable plastic pallet

Info

Publication number: WO2004069671A1
Application number: PCT/AU2004/000131
Authority: WO
Inventors: Adrian Vom Berg; Frantisek Tkac
Original assignee: Clancorp Capital Pty Ltd
Priority date: 2003-02-06
Filing date: 2004-02-05
Publication date: 2004-08-19
Also published as: US20060230988A1

Abstract

A pallet (10) comprises a plurality of members (12) made from plastics material. The members (12) are divided into a set of planks (12A) and a set of beams (12B). The planks (12A) are arranged into two groups, the first group (12A1) which lie on one side of the pallet (10) and the second group (12A2) which lie on an opposite side of the pallet (10) with the beams (12B) lying therebetween. The planks (12A1) and (12A2) are arranged in parallel planes and extend in the same direction to each other, and transversely of the beams (12B). Pins (16) are driven through holes (14A) and (14B) formed in the planks (12A) and the beams (12B) respectively for coupling the planks (12A) to the beams (12B) to form pallet (10).

Description

"Recyclable Plastic Pallet"

Field of the Invention

The present invention relates to a pallet of a type typically used for the storage, stacking and transport of materials such as bricks, bags of particulate or powder materials such as manure, peat, cement; sheet products such as roofing or fencing sheets; and the like.

Background of the Invention

For ease of handling and convenience, many materials are stored, stacked or transported on pallets. A typical pallet has a plurality of spaced apart beams extending in one direction with a plurality of transversely extending slats attached to upper and lower surfaces of the beams. The slats form a load-bearing surface for the material supported by the pallets.

Pallets are most commonly made of wood. However over the last few years there has been an influx of pallets made of plastics material, some being manufactured from recycled materials, others from virgin material. These pallets are manufactured by injection moulding in order to obtain minimum load bearing requirements of the relevant standard, and to maintain production reproducibility.

Nevertheless „ such plastics pallets have two fundamental deficiencies. The first is the inability to handle loads in excess of 1000 kg. The second is that the pallets are non-repairable. With all pallets, be they wood or plastics, an uncontrolled impact can cause damage rendering the pallet unsuitable until repaired. Wooden pallets can be, and are, repaired on a regular basis. The injection moulded plastics pallets are not and are typically destroyed or recycled thus incurring significant replacement cost to the user.

Summary of the Invention

The present invention was developed with a view to providing an alternate form of pallet made from plastics material.

According to the present invention there is provided a pallet including: a plurality of plastics material members, a first set of said members extending in a first direction and across a second set of said members; and, a plurality of mechanical fasteners coupling said first set of members to said second set of members.

Preferably said first set of members comprises a first group of members and a second group of members and wherein said second set of members is disposed between said first and second group of members.

Preferably said first and second group of members extend perpendicular to said second set of members.

Preferably said first and second group of members lie in respective first and second parallel planes, said first and second group of members are spaced by said second set of members .

Preferably each member of said first set of members is of a first common first shape and configuration, and each member of said second set of members is of a common second shape and configuration different to said first shape and configuration.

Preferably each member of said first set of members has a first planar surface. Preferably each member of said first set of members has a second opposite surface formed with a plurality of parallel grooves extending in a direction of the length of said members .

Preferably each member of said second members has a generally I-shaped transverse cross-section, including first and second parallel spaced apart flanges and a web extending centrally between said first and second flanges.

Preferably each of said members is provided with a plurality of transversely extending holes.

Preferably said mechanical fasteners are made of plastics material.

Preferably each fastener comprises a single component which extends through respective registering holes in said first set of members and said second set of members to couple said members together.

Preferably each fastener includes a head, a shank extending from said head and, a tail at an opposite end of said shank, said holes, head and tail relatively configured so that said head is unable to pass through said holes, and said tail passes through said holes in a first direction but not in a second opposite direction.

Preferably said holes are formed adjacent each longitudinal edge of each member of said set of members, with the holes along a first longitudinal edge staggered relative to the holes along a second longitudinal edge.

Throughout this specification the term ^ΛX comprising" is used inclusively, in the sense that there may be other features and/or steps included in the invention not expressly defined or comprehended in the features or steps subsequently defined or described. What such other features and/or steps may include will be apparent from the specification read as a whole.

Brief Description of the Drawings

An embodiment of the present invention will now be described by way of example only with reference to the accompanying drawings in which:

Figure 1 is a plan view of an embodiment of a pallet made in accordance with the present invention;

Figure 2 is a side view of the pallet depicted in Figure 1;

Figure 3 is an end view of the pallet depicted in Figure 1;

Figure 4 is a view of Section A-A of the pallet depicted in Figure 1;

Figure 5 is an enlarged end view of one type of member incorporated in the pallet;

Figure 6 is an end view of a second type of member incorporated in the pallet; and,

Figure 7 is a plan view of a fastener incorporated in the pallet.

Detailed Description of Preferred Embodiment

With reference to the accompanying drawings and in particular Figures 1-4 and 7, an embodiment of a pallet 10 in accordance with this invention comprises a plurality of plastics material members 12 which are divided into two sets, a first set 12A each of which extend in one and the same direction and a second set of members 12B that extend across the first set 12A. A plurality of mechanical fasteners in the form of pins 16 couple the first set 12A of members to the second set 12B.

The first set 12A of members is arranged into two groups, the first group 12A1 lie on one side of the pallet 10 and a second group 12A2 lie on an opposite side of the pallet, the groups 12A1 and 12A2 being separated by the second set 12B of members. More particularly, the first set 12A of members extend perpendicular to the second set 12B, with the first group 12A1 lying in a first plane and forming an upper load bearing surface, and the second group of members 12A2 lying in a second plane parallel to the first plane, and forming a lower load bearing surface.

Referring in particular to Figure 5, each of the members of the first set 12A has a common shape and configuration, being in the general form of a plank with a first planar surface 18 and an opposite surface 20 formed with a plurality of parallel grooves 22 which extend in the direction of the length of that member. For convenience each member of the first set of members will hereinafter be referred to as "plank 12A". The grooves 22 are of equal width and evenly spaced by parallel ridges 24. However, as shown in Figure 5, the ridges 24 adjacent opposite longitudinal edges 26 of the planks 12A are formed of half the width of the remaining ridges 24.

A plurality of holes 14A is formed in the planks 12A. The holes 14A are located to pass from surface 18 to surface 20 through the grooves 22 adjacent the edges 26. As is further apparent from Figure 1, the holes 14A along one longitudinal edge 26 of each plank 12A are staggered relative to the holes 14A along that plank' s opposite longitudinal edge 26. Each hole 14A has a first portion 15 of a constant diameter and a second contiguous portion 17 of constant but smaller diameter.

Each of the members of the set of members 12B has a generally I-shaped transverse cross-section, comprising first and second parallel flanges 28 which are spaced by a centrally located web 30. For convenience the members of the set 12B will be hereinafter referred to as "beams 12B". Holes 14B are formed in the beams 12B on both of the flanges 28 and, for each flange 28 on opposite sides of the web 30. The holes 14B which extend transversely through the beams 12B are of a constant diameter for their entire length. A longitudinally extending semi-circular groove 32 is formed centrally along each flange 28 opposite the web 30 to effectively manage the material flow and cooling consistency during manufacture of the beams 12B particularly when made by an extrusion process.

Referring to Figure 7, each pin 16 is formed as a single unitary element having one end 34 in the shape of a disc, a shank 36 extending from end 34 and an opposite snap lock end 38. The shank 36 is formed with a first portion 40 of a first constant diameter and a co-axial portion 42 of a constant but smaller diameter. A transition portion 44 of short axial length is provided between the portions 40 and 42. The transition portion 44 initially tapers in width toward the portion 42 but at a point 46 approximately halfway between the diameter of portion 40 and the diameter of portion 42 , there is a stepped reduction in the diameter of portion 44. The end 38 is formed with a shoulder 48 adjacent the portion 42 and progressively reduces in outer diameter away from the end 34 finally terminating in a chamfered tip 50. The shoulder 48 has a larger diameter than hole portion 17 and hole 14B but is able to pass through by virtue of inherent resilience of the hole portion 17, hole 14B and/or the pin 16. When the shoulder 48 passes through hole 14B it snap locks on a side of the flange 28 opposite end 34.

The embodiment of the pallet 10 depicted in the accompanying drawings may be constructed as follows. Each of the planks 12A and beams 12B can be extruded from virgin or recycled plastics material. The pin 16 may also be formed from plastics material as extruded cylindrical rods which are then machined to the appropriate shape and configuration. Three beams 12B are placed on a surface evenly spaced apart and parallel to each other. Next, three planks 12A2 making up the lower load bearing surface are placed transversely across the beams 12B with two of the planks 12A2 extending along opposite edges of the pallet 10 while the remaining plank 12A extends centrally therebetween. With the holes 14A and 14B in the planks 12A2 and beams 12B in registration, respective pins 16 are driven through the planks 12A2 into the beams 12B with end 38 first. The pins 16 and holes 14A and 14B are relatively configured to provide a snug interference fit with the end 34 located in the counter-sunk portion 15, and the shoulder 48 and end 38 located on the side of each flange 28 opposite the planks 12A2. The end 38 is unable to pass back through hole 14B due to shoulder 48. With the three planks 12A2 fastened to the beams 12B, the ensemble is turned over and the planks 12A1 forming the upper load bearing surface placed at appropriate locations along the bearers 12B and fastened by the pins 16, to form a finished or complete pallet 10.

The pallet 10 is used in an identical manner to traditional wooden pallets. In the event of the breakage of a plank 12A, the plank 12A can be completely removed from the pallet by "drilling out" the pins 16 attaching that plank 12A to the beams 12B replacing the broken plank with a fresh plank and then attaching that plank with the use of further pins 16. In an alternate method for removing a broken plank 12A, it may be possible to shear the pins 16 by applying a transverse impact onto the ends 38 for example by use of a hammer or with a chisel and hammer.

Now that an embodiment of the pallet 10 has been described in detail it will be apparent to those skilled in the relevant arts that numerous modifications and variations may be made without departing from the basic inventive concepts. For example, in the illustrated pallet 10, the planks 12A and beams 12B are of different shape and configuration. However this need not necessarily be the case. For example, the planks and beams may have an identical shape and configuration, such as in the form of a rectangular tube having parallel wide sides and parallel narrow sides, with the planks lying on their wide sides and the beams lying on their narrow sides. The number of planks forming each of the upper and lower surfaces of the pallet 10 may be varied as can be the number of beams, although it is envisaged that for a pallet 10 of a size the same as the commonly available wooden pallets, three beams would be a desired minimum. For smaller pallets, two beams may be sufficient. For larger pallets more than three beams may be desirable. In addition, for larger pallets diagonally extending beams may also be included. The shape and configuration of the pins 16 may also be varied. The only requirement of the pins 16 is that they fasten the planks to the beams. Fasteners of a different shape and construction to the pins 16 may be used including multi- component fasteners to achieve the same effect as the pins 16. It is envisaged that the planks 12A, beams 12B and pins 16 will all be made via an extrusion process from common grades of HDPE. However it should be recognised that the components may be made from any number of available plastic resins, either individually or in combination and from virgin or recycled materials. The pins 16 may be made from different materials from the planks 12A and beams 12B. Talc filled, or glass fibre reinforced resin are considered particularly suitable to ensure sheer strength of the pin 16 is in excess of that anticipated during service.

All such modifications and variations together with others that would be obvious to persons skilled in the relevant art are deemed to be within the scope of the present invention the nature of which is to be determined from the above description and appended claims.

Claims

The claims defining the invention are as follows:

1. A pallet including:

a plurality of plastics material members, a first set of said members extending in a first direction and across a second set of said members; and,

a plurality of mechanical fasteners coupling said first set of members to said second set of members.

2. A pallet according to claim 1 wherein said first set of members comprises a first group of members and a second group of members and wherein said second set of members is disposed between said first and second group of members.

3. A pallet according to claim 2 wherein said first and second group of members extend perpendicular to said second set of members.

4. A pallet according to claim 2 or 3 wherein said first and second group of members lie in respective first and second parallel planes, said first and second group of members are spaced by said second set of members.

5. A pallet according to any one of claims 1-4 wherein each member of said first set of members is of a first common first shape and configuration, and each member of said second set of members is of a common second shape and configuration different to said first shape and configuration.

6. A pallet according to any one of claims 1-5 wherein each member of said first set of members has a first planar surface.

7. A pallet according to any one of claims 1-6 wherein each member of said first et of members has a second opposite surface formed with a plurality of parallel grooves extending in a direction of the length of said members .

8. A pallet according to any one of claims 1-7 wherein each member of said second members has a generally I- shaped transverse cross-section, comprising first and second parallel spaced apart flanges and a web extending centrally between said first and second flanges.

9. A pallet according to any one of claims 1-8 wherein each of said members is provided with a plurality of transversely extending holes.

10. A pallet according to claim 1 wherein each fastener comprises a single component which extends through respective registering holes in said first set of members and said second set of members to couple said members together.

11. A pallet according to claim 10 wherein each fastener includes a head, a shank extending from said head and, a tail at an opposite end of said shank, said holes, head and tail relatively configured so that said head is unable to pass through said holes, and said tail passes through said holes in a first direction but not in a second opposite direction.

12. A pallet according to any one of claims 9-11 wherein said holes are formed adjacent each longitudinal edge of each member of said set of members, with the holes along a first longitudinal edge staggered relative to the holes along a second longitudinal edge.

13. A pallet according to any one of claims 1-12 wherein said mechanical fasteners are made of plastics material.