WO2007066097A1

WO2007066097A1 - Pallet

Info

Publication number: WO2007066097A1
Application number: PCT/GB2006/004544
Authority: WO
Inventors: Henry Stevens; Peter Morris; Paul Nugent
Original assignee: Pvaxx Research And Development Limited
Priority date: 2005-12-05
Filing date: 2006-12-05
Publication date: 2007-06-14
Also published as: GB2432826A; GB2432826B; GB0524807D0

Abstract

A pallet is described having upper and lower pallet portions, each of which has a respective engagement element for engagement with the other element through a relative rotational or lateral movement of the upper and lower pallet portions. In one embodiment, the upper and/or the lower pallet portion is arranged to flex during the engagement process to allow the engagement of secondary engagement elements.

Description

PALLET TECHNICAL FIELD The present invention relates to pallets such as load bearing pallets and in particular to load bearing pallets formed from two or more connectable parts.

BACKGROUND ART Apparatus for storing and transportation of goods, particularly bulk goods, has to be robust enough to withstand the high impact stresses and adverse environmental conditions that it may encounter during normal operation.

Wooden pallets for storing and transporting goods are well known in the art and are defined by standards such as ISO Standard No. 6780. Such pallets are strictly defined in the standard, and other standards define the tests to which they must be subjected before being judged to be fit for use.

However, wooden pallets suffer from a number of disadvantages. They are susceptible to rotting, and woodworm, which means that their working life is relatively short, and they may endanger the goods carried on them. They are relatively easy to pierce with sharp objects, relatively heavy, and difficult to recycle. The Applicant's WO-A-2005/090175 discloses a pallet moulded from a plastics material having top and bottom pallet elements which are joined to provide the pallet. This pallet is configured to be used in the same way as a wooden pallet, being adapted for transport by a fork lift device where the device's fork is placed between the top and bottom pallet elements of the pallet. When transported in this way, and the pallet is raised from a ground surface, the bottom pallet element is held above the ground surface by the join joining the pallet elements together. While this pallet is a useful alternative to the wooden pallets described above, the Applicant has found that there is a potential for the top and bottom pallet elements to separate in use when being transported by a fork lift device.

It is an object of at least one of the preferred embodiments of the present invention to overcome or ameliorate at least one of the deficiencies of the prior art, or at least to provide a suitable alternative thereto. SUMMARY OF THE INVENTION

According to a first aspect of the invention there is provided a pallet comprising:

a first pallet portion extending in a first plane;

a second pallet portion extending in a second plane; and

a first engagement portion on the first pallet portion for interlocking engagement with a second engagement portion on the second pallet portion to form the pallet, wherein the first and second engagement portions are configured to move from an unengaged to an engaged condition on movement of the pallet portions relative to each other substantially in a plane parallel to the first and second planes.

The various forces that pallets are subjected to tend to be directed in a substantially normal direction with respect to a plane on which the pallet extends. Advantageously, the engagement configuration of the pallet of the present invention may be more robust than prior art pallets formed from two portions, since the first and second pallet portions are engageable in a parallel rather than normal direction with respect to the pallet plane. Preferably, said relative movement is rotational movement or lateral movement. Advantageously, lateral movement and particularly rotational movement for interlocking the first and second pallet portions is rarely replicated in standard use of the pallet. Therefore, the first and second pallet portions are less likely to be unintentionally disconnected during normal use. Preferably, at least one of the first and second pallet portions comprises a plurality of feet, the first engagement portion being on at least one of said feet. Preferably, the first pallet portion has a plurality of feet arranged to oppose a plurality of feet on the second pallet portion when the first and second pallet portions are interlockingly engaged to form the pallet, and the first and second engagement portions are on at least one pair of opposed feet.

Preferably, the first engagement portion is a female portion on one foot of said opposed feet pair and the second engagement portion is a male portion on the other foot of said opposed feet pair. Preferably, the male portion is relatively rotatable in the female portion between an unlocked position and a locked position.

Preferably, one foot of at least one other pair of opposed feet comprises a second male portion and another foot of said at least one other pair of opposed feet comprises a second female portion for receiving the second male portion therein. Preferably, the first mentioned male and female portions are configured such that the at least one other feet pairs are opposed when the first male and female portions are in the locked position and not opposed when the first male and female portions are in the unlocked position.

Preferably, at least part of the pallet is flexible in directions substantially perpendicular to the first or second planes. Preferably, flexion of at least part the pallet is required to engage a pair of opposed second male and female portions. Advantageously, when opposed second male and female portions - A - are engaged, the resistance to flexion of the pallet acts to maintain the engagement of opposed second male and female portions.

Preferably, the first pallet portion is a top pallet portion and the second pallet portion is a bottom pallet portion, and each of the top and bottom pallet portions comprise nine said feet forming nine opposed feet pairs when the engagement portions are engaged to form the pallet. Preferably, the nine feet on each of the top and bottom pallet portions are arranged in a respective 3x3 grid and the first engagement portion is on a central foot of the one of the first and second pallet portions and the second engagement portion is on a central foot of another of the first and second pallet portions.

The first and second pallet portions may be moulded from a filled plastics material. The first and second engagement portions may be releasable.

According to another aspect of the present invention there is provided a pallet comprising:

a first pallet portion extending in a first plane;

a second pallet portion extending in a second plane; and

at least first and second mutually distinct engagement formations, each formation having portions on each of the first and second pallet portions.

Preferably, the portions of the first engagement formation comprise first and second engagement portions for interlocking engagement to form the pallet, wherein the first and second engagement portions are configured to move from an unengaged to an engaged condition on movement of the pallet portions relative to each other substantially in a plane parallel to the first and second planes. The portions of the first formation may be configured for mutual rotational interlocking engagement. Also, the portions of the second formation may be configured for mutual frictional engagement or for snap-locking engagement.

Preferably, the first pallet portion has a plurality of feet arranged to oppose a plurality of feet on the second pallet portion when the first and second pallet portions are interlockingly engaged to form the pallet, and the first and second engagement formations are on respective pairs of opposed feet.

Preferably, the first engagement formation comprises a female portion on one foot of an opposed feet pair and a male portion on the other foot of said opposed feet pair. Also preferably, the second engagement formation comprises a second female portion on one foot of a second said opposed feet pair and a second male portion on the other foot of said second opposed feet pair. The first mentioned male portion may be relatively rotatable in the first mentioned female portion between an unlocked position and a locked position.

Preferably, the first male and female portions are configured such that feet pairs not including the first mentioned foot pair are opposed when the first male and female portions are in the locked position and not opposed when the first male and female portions are in the unlocked position.

Preferably, at least part of the pallet is flexible in directions substantially perpendicular to the first or second planes. Preferably, flexion of at least part the pallet is required to engage a pair of opposed second male and female portions. Advantageously, when opposed second male and female portions are engaged, the resistance to flexion of the pallet acts to maintain the engagement of opposed second male and female portions.

Preferably, the first pallet portion is a top pallet portion and the second pallet portion is a bottom pallet portion, and wherein each of the top and bottom pallet portions comprise nine said feet forming nine said opposed feet pairs when the engagement formations are engaged to form the pallet. Further preferably, the respective nine feet on each of the top and bottom pallet portions are arranged in a 3x3 grid and the first male and female portions are on a respective foot of a central said foot pair.

The pallet may comprise two or more said second engagement formations. Also, the first and second pallet portions may be moulded from a filled plastics material. Preferably, the engagement portion pairs are releasable. The spatial terms "upper", "lower", "top" and "bottom" as used in the description and claims are meant in a general, relative and convenient sense, and are not to be interpreted in a strict, literal sense.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings in which:

Figure 1 is a perspective view of a pallet according to an embodiment of the present invention;

Figures 2 to 4 are plan, side elevation and bottom views of the pallet illustrated in Figure 1 ; Figures 5, 6 and 7a are plan, side elevation and bottom perspective views, respectively, of an upper portion of the pallet illustrated in Figure 1 ;

Figures 7b and 7c show side elevation partial cross sections of upper and lower portions of the pallet in respectively joined and semi-joined configurations; Figures 8 to 11 are plan, side elevation, bottom and perspective views of a lower portion of the pallet illustrated in Figure 1 ; and

Figure 12 is a side elevation of a stack of alternating upper and lower pallet portions of the pallet illustrated in Figure 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION Referring to Figures 1 to 4, a preferred embodiment of the present invention is a pallet 10 comprising a first pallet portion in the form of an upper portion 12 and a second pallet portion in the form of a lower pallet portion 14. The upper pallet portion 12 is illustrated in Figures 5, 6 and 7a while the lower pallet portion 14 is illustrated in Figures 8 to 11. As illustrated in Figure 7a the upper pallet portion has nine feet 20, arranged in a 3x3 grid on an underside surface 22 thereof. Also, as illustrated in Figures 8 and 11 the lower pallet portion 14 has nine feet 24 arranged in a 3x3 grid on an upper side surface 26 thereof. The feet 20, 20a on the upper pallet portion 12 and the feet 24, 24a on the lower pallet portion 14 are arranged such that when the upper and lower pallet portions 12 and 14 are joined together to form a pallet 10, the feet 20 on the upper pallet portion oppose respective feet 24 on the lower pallet portion 14.

Releasable interlocking engagement means in the form of a tongue 28 on a central foot 20a of the upper pallet portion 12 and a tongue receiving portion

30 on a central foot 24a of the lower pallet portion 14 is provided for releasable interlocking engagement of the upper and lower pallet portions 12 and 14 to form a pallet 10. The feet 20 on the periphery of the upper pallet portion 12 have respective secondary male portions 32 extending therefrom, and the feet 24 on the periphery of the lower pallet portion 14 have secondary female portions 34 thereon. The secondary female portions 34 are configured to receive the secondary male portions 32 when the other pallet portion 12 is joined to the lower pallet portion 14 to form the pallet 10. In an alternative arrangement, each or at least some of the secondary male portions 32 are configured for releasable snap-locking engagement with a respective one of the secondary female portion 34.

As illustrated in Figure 7a, the tongue 28 lies on a plane parallel with a plane upon which the upper pallet portion generally lies. The tongue 28 also extends in a direction towards foot 20a. An aperture of the tongue receiving portion 30 is complementary to the shape of the tongue 28. However, the orientation of the aperture 36 with respect to the lower pallet portion 14 is such that when the tongue 28 is initially inserted in the female portion 30 the peripheral feet 20 of the upper pallet portion 12 do not oppose corresponding respective feet 24 of the lower pallet portion 14. To interlock the upper and lower pallet portions 12 and 14 together, the male portion 28 is inserted through the aperture of the female portion 30 and the upper pallet portion 12 is rotated relative to the lower pallet portion 14 until each peripheral foot 20 of the upper pallet portion 12 oppose respective corresponding feet 24 of the lower pallet portion 14. The secondary male portions 32 are then inserted in their respective secondary female portions 34. Some torsional flexing of either or both of the upper and lower pallets portions 12, 14 is required to be able to insert the secondary male portions 32 into the secondary female portions 34. Torsional flexing will generally need to be applied in directions substantially perpendicular to the planes upon which the pallet portions lie; arrows 11, as illustrated in Figure 1 , show example directions for the application of torsional flexion. The inserting of the secondary male portions 32 into their respective secondary female portions 34 aids in preventing rotation of the upper pallet portion 12 with respect to the lower pallet portion 14 when the tongue 28 is received in the tongue receiving portion 30 and therefore prevents accidental separation of the upper and lower pallet portions 12, 14. Furthermore, once upper and lower pallet portions 12, 14 are joined, their resistance to flexion in conjunction with the holding effect of the interlocking of tongue 28 with tongue receiving portion 30, helps to retain the secondary male portions 32 in their respective secondary female portions 34; this further helps to keep upper and lower pallet portions 12, 14 joined. As will be understood, the upper and lower pallet portions 12, 14, when joined together, can be separated by torsionally flexing either or both of the upper and lower pallet portions 12, 14 to remove the secondary male portions 32 from their respective secondary female portions 34 and rotating the upper pallet portion 12 with respect to the lower pallet portion 14 to remove the tongue 28 from the tongue receiving portion 30.

Figure 7b shows a side elevation partial cross section of pallet 10 along a line 13 as illustrated in Figure 4. The upper and lower pallet portions 12 and 14 are joined both by the mating of tongue 28 of foot 20a with tongue receiving aperture 30 of foot 24a and also by the mating of secondary male portions 32 of feet 20 with corresponding secondary female portions 34 of feet 24. As shown, the separation between the upper and lower pallet portions 12 and 14 is S; the height of foot 20 and its associated secondary male portion 32 is S₁; and the height of foot 24 is S₂. As can be seen from Figure 7b, the sum of the distances Si and S₂ is greater than the distance S; it is this relationship that necessitates the above torsional flexing of either or both of the upper and lower pallets portions 12, 14 when the pallet 10 is assembled.

Figure 7c shows the pallet 10 of Figure 7b in a semi-joined configuration and illustrates the torsional flexion required for the secondary feet 20, 24 to mate.

In particular, Figure 7c illustrates the pallet 10 when the tongue 28 of foot

20a and the tongue receiving aperture 30 of foot 24a have been engaged, and in which the upper pallet portion 12 has been flexed substantially in a direction indicated by arrow 11 to allow mating of the feet 20, 24. As illustrated, the deflection of upper pallet portion 12 is a distance δS. As those skillied in the art will appreciate, for secondary male portion 32 to pass foot 24 and hence be able to mate with secondary female portion 34, the sum of distances S and δS should be greater than or equal to the sum of the distances Si and S2. The upper and lower pallet portions 12 and 14 of the preferred embodiment are manufactured from a filled plastics material. Preferably, the plastics material comprises PVA or PVOH and the filler is preferably a mineral-based filler such as sand, or a carbonate material. The pallet may be manufactured to perform with internationally recognised standards such as ISO Standard No. 6780. In another embodiment the pallet 10 has a length of between about 1207 and 1211mm and a width of between about 1006 and 1010mm. Each of the upper and lower pallet portions 12 and 14 of the preferred embodiment are manufactured by rotational moulding techniques as described in International Patent Application No. PCT/GB2005/001125. Each of the upper and lower pallet portions 12 and 14 may be hollow or foam-filled using any suitable foam filling material, such as HDPE, for example.

As illustrated in Figure 10, the lower pallet portion further comprises recesses 38 on a lower side 39 thereof which aid in improving the torsional integrity of the lower pallet portion 14 and also decrease the volume of the lower pallet portion 14 and therefore reduce the amount of material required to make the lower pallet portion and reduce its resultant weight. Similarly with the upper pallet portion 12, as illustrated in Figures 5 to 7, there are included holes 40 which also increase the torsional and structural integrity of the upper pallet portion 12 and reduce its volume and weight. The upper pallet portion 12 also includes ridges 42 on its upper and underside surfaces 44, 22 also for increasing the structural integrity thereof.

The upper and lower portions 12, 14 are configured to be stacked when not in use and not joined to form a pallet 10, alternatively, as illustrated in Figure 12.

When stacked, the feet 24, 24a of the lower pallet portions 14 nest in corresponding feet receiving portions 46 on the upper surface 44 of the upper pallet portion 12. This is achieved by the lower pallet portion 14 being upside- down compared to the orientation of the upper pallet portions 12. Also, the feet 20, 20a partially nest in feet receiving portions 48 on the upper side surface 26 of the lower pallet portion 14. When stacked, the upper and lower pallet portions 12, 14 rest on one another and are not locked together, such as when joined to form a pallet.

While the invention has been described in reference to its preferred embodiments, it is to be understood that the words which have been used are words of description rather than limitation and that changes may be made to the invention without departing from its scope as defined by the appended claims.

Claims

CLAIMS:

1. A pallet comprising:

a first pallet portion extending in a first plane;

a second pallet portion extending in a second plane; and

2. The pallet of claim 1 wherein said relative movement is rotational movement or lateral movement.

3. The pallet of claim 1 or 2 wherein at least one of the first and second pallet portions comprises a plurality of feet, the first engagement portion being on at least one of said feet.

4. The pallet of claim 1 or 2 wherein the first pallet portion has a plurality of feet arranged to oppose a plurality of feet on the second pallet portion when the first and second pallet portions are interlockingly engaged to form the pallet, and the first and second engagement portions are on at least one pair of opposed feet.

5. The pallet of claim 4 wherein the first engagement portion is a female portion on one foot of said opposed feet pair and the second engagement portion is a male portion on the other foot of said opposed feet pair.

6. The pallet of claim 5 wherein the male portion is relatively rotatable in the female portion between an unlocked position and a locked position.

7. The pallet of any of claims 4 to 6 wherein one foot of at least one other pair of opposed feet comprises a second male portion and another foot of said at least one other pair of opposed feet comprises a second female portion for receiving the second male portion therein.

8. The pallet of claim 7 wherein at least part of at least one of said first or second pallet portions is flexible in directions substantially perpendicular to said first or second planes to allow mating of said second male portion with the corresponding female portion.

9. The pallet of claim 7 or 8 wherein the first mentioned male and female portions are configured such that the at least one other feet pairs are opposed when the first male and female portions are in the locked position and not opposed when the first male and female portions are in the unlocked position.

10. The pallet of any of claims 3 to 9 wherein the first pallet portion is a top pallet portion and the second pallet portion is a bottom pallet portion, and wherein each of the top and bottom pallet portions comprise nine said feet forming nine opposed feet pairs when the engagement portions are engaged to form the pallet.

11. The pallet of claim 10 wherein the nine feet on each of the top and bottom pallet portions are arranged in a respective 3x3 grid and the first engagement portion is on a central foot of the one of the first and second pallet portions and the second engagement portion is on a central foot of another of the first and second pallet portions.

12. The pallet of claim 3, wherein at least another one of said feet comprises a second male portion operable to engage with a second female portion on the other pallet portion.

13. The pallet of claim 12, wherein a least part of at least one of said first and second pallet portions is flexible in directions substantially perpendicular to said first or second planes to allow mating of said second male portion with the corresponding female portion.

14. The pallet of any preceding claim wherein the first and second pallet portions are moulded from a filled plastics material.

15. The pallet of any preceding claim wherein the first and second engagement portions are releasable.

16. A pallet comprising:

a first pallet portion extending in a first plane;

a second pallet portion extending in a second plane; and

17. The pallet of claim 16 wherein the portions of the first engagement formation comprise first and second engagement portions for interlocking engagement to form the pallet, wherein the first and second engagement portions are configured to move from an unengaged to an engaged condition on movement of the pallet portions relative to each other substantially in a plane parallel to the first and second planes.

18. The pallet of claim 16 or 17 wherein the portions of the first formation are configured for mutual rotational interlocking engagement.

19. The pallet of claim 16, 17 or 18 wherein at least part of at least one of said first or second pallet portions is flexible in directions substantially perpendicular to said first or second planes.

20. The pallet of any of claims 16 to 19 wherein the portions of the second formation are configured for mutual frictional engagement or for snap-locking engagement.

21. The pallet of any of claims 16 to 20 wherein the first pallet portion has a plurality of feet arranged to oppose a plurality of feet on the second pallet portion when the first and second pallet portions are interlockingly engaged to form the pallet, and the first and second engagement formations are on respective pairs of opposed feet.

22. The pallet of claim 21 wherein the first engagement formation comprises a female portion on one foot of an opposed feet pair and a male portion on the other foot of said opposed feet pair.

23. The pallet of claim 22 wherein the second engagement formation comprises a second female portion on one foot of a second said opposed feet pair and a second male portion on the other foot of said second opposed feet pair.

24. The pallet of claim 22 or 23 wherein the first mentioned male portion is relatively rotatable in the first mentioned female portion between an unlocked position and a locked position.

25. The pallet of any of claims 21 to 24 wherein the first male and female portions are configured such that feet pairs not including the first mentioned foot pair are opposed when the first male and female portions are in the locked position and not opposed when the first male and female portions are in the unlocked position.

26. The pallet of any of claims 21 to 25 wherein the first pallet portion is a top pallet portion and the second pallet portion is a bottom pallet portion, and wherein each of the top and bottom pallet portions comprise nine said feet forming nine said opposed feet pairs when the engagement formations are engaged to form the pallet.

27. The pallet of claim 26 wherein the respective nine feet on each of the top and bottom pallet portions are arranged in a 3x3 grid and the first male and female portions are on a respective foot of a central said foot pair.

28. The pallet of any of claims 16 to 27 comprising two or more said second engagement formations.

29. The pallet of any of claims 16 to 28 wherein the first and second pallet portions are moulded from a filled plastics material.

30. The pallet of any of claims 16 to 29 wherein the engagement portion pairs are releasable.

31. A method for joining two or more pallet portions comprising:

engaging a first female engagement portion on a first pallet portion with a first male engagement portion on a second pallet portion;

relatively rotating and/or laterally moving the first and second second pallet portions to move them from an unlocked to a locked position; and

torsionally flexing at least part of at least one of said first or second pallet portions to allow engagement of at least one second male engagement portion on either said first or second pallet portion with at least one second female engagement portion on the other of said first or second pallet portions.