WO2013022400A1

WO2013022400A1 - Pallet

Info

Publication number: WO2013022400A1
Application number: PCT/SE2012/050841
Authority: WO
Inventors: Jörgen HAGLUND
Original assignee: Individual
Current assignee: Individual
Priority date: 2011-08-08
Filing date: 2012-07-18
Publication date: 2013-02-14
Anticipated expiration: 2014-02-08
Also published as: EP2741967A1; EP2741967A4; SE1150734A1

Abstract

A plastic pallet comprising an upper load-bearing plate (1) supported above three parallel rails (2) that extend in the longitudinal direction of the pallet, whereby each 'one of the rails (2) is located with the aid of three spacer elements (3) at a determined distance below the load-bearing plate (1) of the pallet, whereby a locking means is arranged from the lower surface of the rail (2) and extending through a central hole in each one of the spacer elements (3), and the locking means is provided at its upper end with a pair of elastic arms that extend upwards and that are provided with locking pegs that protrude to the sides arranged to grip onto an upwardly facing surface of the load-bearing plate (1), and that a locking element (4) that can be removed is arranged to be inserted in from the upper surface of the load-bearing plate (1) and protruding into the locking means (5), whereby the locking element (4) is provided with at least one radially protruding locking peg arranged to, after rotation of the locking element (4), lock this element fixed in the load-bearing plate (1) through this being provided with a corresponding indentation for the locking peg and in this way preventing it being possible that the locking means can be freed from the load-bearing plate (1) when the locking element (4) is fixed into the load-bearing plate (1).

Description

PALLET

The present invention concerns a pallet manufactured from a plastic material .

Pallets have long been used to transport goods, and normally have a standard dimension of 800 X 1200 mm, such as, for example, what is known as a EUR pallet. Pallets normally comprise a load-bearing surface, supporting rails intended to rest on a surface and blocks that unite the rails with the load-bearing surface. It is usual that three rails are arranged under the load-bearing surface, one along each long side of the load-bearing surface and one centrally located under the load-bearing surface, which rail also extends in the longitudinal direction of the pallet. The blocks are arranged between each rail and the load-bearing surface, one block at each end of each rail, and one centrally placed between them. There is in this way formed under the load- bearing surface two longitudinal channels, into which the forks of a fork-lift truck, or other pallet lifter, can be introduced in order to lift the pallet. With the design of the pallet described above it is possible to introduce the forks of a fork-lift truck into the transverse direction of the pallet, in which case the forks are introduced into the space between the rails and the load-bearing surface.

Pallets have most often been manufactured from wood, but in recent times also other materials such as sheet metal, paperboard and plastic have started to be used.

A pallet manufactured from a plastic material is previously known from WO00/68100, where a load-bearing plate is united with underlying rails through a screw joint in each one of the spacer blocks that locate the load-bearing plate at an elevated distance above the rails.

Further, through the Swedish patent 521 852 C2 also a pallet that is manufactured from a plastic material is known, where the pallet is built up from a number of modules that can be exchanged in the event that any one of the modules becomes damaged. The pallet comprises a load-bearing plate and three parallel rails under the load-bearing plate, each one of which rails is united with the plate through three spacer blocks. The spacer blocks comprise a central cavity through which a locking pin can be introduced from below and with the aid of locking means introduced into the locking pin from below can be locked such that the rails are fixed united to the load-bearing plate through the spacer blocks.

The Swedish patent mentioned above specifies a solution in which it is to be possible to exchange damaged parts of a pallet, through the pallet being built up from modules that can be exchanged. This solution, however, is such that it requires that all load is removed from the pallet in order to be able to exchange a damaged part, and furthermore, tools are required to be able to free the locking pin and the locking means in order to make possible the release of at least one of a spacer block and a rail from the load-bearing plate .

One general purpose of the invention is to achieve a pallet of plastic with low weight and high strength, and that furthermore is designed to reduce the risk that the components of the pallet are damaged by, for example, fork- lift trucks, and which pallet furthermore is designed such that it is possible to exchange in a simple manner individual parts of the pallet that have been damaged. A first specific purpose of the present invention is to achieve a pallet that provides the possibility to release in a simple manner a damaged part from the load-bearing plate of the pallet, and to carry this out also when a load remains in place on the pallet.

A further specific purpose of the invention is to achieve a pallet that minimises the risk that it is damaged by the forks of a fork-lift truck if these are applied in an erroneous manner relative to what has been intended.

A further specific purpose of the invention is to achieve a pallet that has low weight and even so increased load-bearing capacity compared with prior art plastic pallets.

The first specific purpose of the invention is achieved with a plastic pallet that comprises an upper load-bearing plate supported above three parallel rails each one of which is located with the aid of three spacer elements at a determined distance below the load-bearing plate of the pallet, and where a locking means is, according to the invention, arranged from the lower surface of the rail and extending through a central hole in each one of the spacer elements, and the locking means is provided at its upper end with a pair of elastic arms that extend upwards and that are provided with pegs that protrude to the sides arranged to grip onto an upwardly facing surface of the load-bearing plate, and that a locking element that can be removed is arranged to be inserted in from the upper surface of the load-bearing plate and protruding into the locking means, and whereby the locking element is provided with at least one protruding locking peg arranged to, after rotation of the locking element, lock this element fixed in the load-bearing plate through this being provided with a corresponding indentation for the locking peg and in this way preventing it being possible that the locking means can be released from the load-bearing plate when the locking element is fixed into the load-bearing plate.

The further specific purpose of the invention, that of achieving a pallet that minimises the risk that it becomes damaged, is achieved through the load-bearing plate being provided on its lower surface by the side of the spacer elements at their outermost edges with bevels that extend inwards from the edge of the load-bearing plate, and through, where relevant, also the rails at their upper surfaces, at least at the side of the spacer elements, being provided with bevelled side edges, or preferably an arched upper surface.

The further specific purpose, that of achieving a pallet that has low weight and even so a higher load-bearing capacity than plastic pallets according to the prior art, is achieved through the load-bearing plate demonstrating a number of penetrating principally circular holes evenly distributed across the surface of the plate, and where preferably reinforcement webs are arranged diametrically through the circular holes in a region perpendicular to the longitudinal direction of the pallet at spacer elements and also diametrically through the circular holes along the diagonals of the pallet.

The invention will be described below in the form of a non- limiting embodiment, illustrated in the attached_, drawings, where Figure 1 shows a pallet according to the invention in a perspective view, Figure 2 shows a detail of the pallet in Figure 1, to be more precise an external corner of the load- bearing plate of the pallet seen from above, Figure 3 shows the same corner as that shown in Figure 2 but in a view from below, Figure 4 shows an end part of a rail of the pallet in a view obliquely from above, Figure 5 shows an end view of a spacer element of the pallet, Figure 6 shows a perspective view of a locking means of the pallet, Figure 7 shows a side view of a locking means with a locking element laid on top of the locking means, and Figure 8 shows a perspective view of a corner of the pallet with the component parts assembled. Thus, Figure 1 shows a perspective view of a pallet according to the invention, comprising a load-bearing plate 1, three parallel rails 2 that extend under the load-bearing surface, each one of which rails is united with the load-bearing plate 1 by three spacer elements 3, such that the rails are located at a determined distance under the load-bearing plate. All parts of the pallet are manufactured from a plastic material, and they have been designed such that the separate parts may be exchanged for corresponding other parts; to allow this, the complete pallet has been designed such that it can be assembled and disassembled. The drawing reveals also a locking element 4 located above each one of the spacer elements 3, thus a total of nine locking elements 4 visible in the drawing. The function of the locking elements 4 and the locking means 5 that interact with these will be described in more detail below.

The load-bearing plate 1 is, as has been mentioned above, of plastic material, and in order to reduce its weight a number of holes 6 have been located perpendicularly through the plate in a pre-determined pattern. In order to further reinforce the load-bearing plate 1, there are arranged in a number of these holes 6 diametrically located reinforcement webs 7, extending through the complete thickness of the load- bearing plate. It is appropriate that these reinforcement webs be arranged through the holes 6 in regions 8 perpendicular to the longitudinal direction of the load- bearing plate 1 at the spacer elements 3, thus located in three regions 8 as is shown in Figure 1. It is appropriate also, or alternatively, that the reinforcement webs 7 be arranged through holes 6 in the diagonal directions 9 of the load-bearing plate 1.

As is also made clear by Figure 1, bevels 10 are arranged at the lower surface of the load-bearing plate 1, in the regions between the spacer elements 3, at the edges of the plate. This is made clear also by Figure 3 and Figure 8. The bevels 10 extend a distance in from the edge of the load-bearing plate 1 and function as ramp surfaces for the forks of a fork-lift truck, such that if these are inserted somewhat erroneously against the edge of the pallet, the ramp surfaces can guide the forks correctly. The risk that the edge of the load-bearing plate 1 of the pallet becomes damaged is in this way reduced.

One corner of the load-bearing plate 1 of the pallet according to the invention is shown in Figure 2 and Figure 3. The view from above shown in Figure 2 makes it clear that the outer corner of the load-bearing plate is rounded. Further, also the region 8 with reinforcement webs 7 arranged in the transverse direction of the plate and the diagonally arranged reinforcement webs 9 are made clear. A penetrating hole 11 is arranged at the corner of the load-bearing plate 1 for the connection of a locking means, not shown in the drawing, for the attachment of a spacer element 3 under it. Around the penetrating hole 11 there is arranged also a circular indentation 12 from above for the reception of a locking element 4 as has been mentioned above. At two diametrical locations of the circular indentation 12, there are arranged vertical grooves 13 that extend from the upper surface of the load-bearing plate down to the bottom of the circular indentation 12, and the vertical grooves 13 are connected at the bottom of the circular indentation 12 to an undercut indentation that extends peripherally a small distance to the side from the vertical grooves. The vertical grooves 13 are intended to receive a pair of protruding pegs on the locking element 4, as will be described in more detail below. The penetrating hole 11 for the locking means 5 is, as is made clear by the drawing, not circular, in order to achieve guiding of the locking means 5 in a predetermined direction. It is possible also that a pair of diametrically arranged indentations 14 are arranged at the edge of the penetrating hole 11 in the bottom of the circular indentation in order to receive a pair of locking pegs on the locking means 5, as also will be described in more detail below.

The view according to Figure 3, which shows a corner of the load-bearing plate 1 seen from below, makes it clear that the lower surface around the penetrating hole 11 for the locking means is provided with a number of protruding guides 15 in order to guide and support a spacer element 3. As is made clear, the bevels 10 are arranged at the outermost edges of the load-bearing plate 1 at the lower surface of the load- bearing plate in the region outside of the location at which it is intended that the spacer element 3 is to be placed.

Corresponding penetrating holes 11 for locking means 5 and corresponding circular indentations 12, with corresponding guides 15 at the lower surface of the load-bearing plate 1, are arranged not only at the four corners of the pallet, but also at the centre of each one of the sides and at the centre of the pallet. There are thus nine such arrangements on the oad-bearing plate, i.e. one for each of the spacer elements

Figure 4 shows an end part of a rail 2 for the pallet according to the invention. The drawing makes it clear that the rail 2 has an arched upper surface 16 and that it is provided with a large number of vertical penetrating holes 17. It makes also clear that the rail has a rounded end. A penetrating, non-circular hole 18 is located before the rounded end, through which hole the locking means 5 mentioned above can pass, and furthermore a circular indentation 19 is arranged with a plane bottom surface for the reception of the lower end of a spacer element 3. Upwardly pointing guides 20 are also located in the circular indentation 19 to guide the spacer element 3.

A circular indentation is present also on the lower surface of the rail 2, not shown in the drawings, which circular indentation is concentric with the circular indentation 19 on the upper surface of the rail. The circular indentation on the lower surface of the rail is arranged such that it is possible for the circular foot of the previously mentioned locking means to be accommodated in this circular indentation, and the rail 2 obtains in this way an essentially plane lower surface.

Through the arched upper surface 16 of the rail 2 there is created a ramp surface to guide forks of a fork-lift truck if the forks have been inserted too low in the transverse direction against the rail 2. The rounded end of the rail 2 provides also a corresponding guidance in the sideways direction for a fork that has been inserted too close to the rail, or alternatively it ensures that the pallet is displaced somewhat in a sideways direction, when the fork is to be inserted parallel with the rail 2. The arching of the rail increases also its rigidity, and provides in this way increased stability to the pallet according to the invention. Corresponding non-circular penetrating holes 18, circular indentations 19 and upwardly directed guides 20 are arranged also at the centre of each rail, such that a rail demonstrates three reception locations for spacer elements 3. The spacer element 3 that is shown in an end view in Figure 5 has a cylindrical external jacket 21 and a similar internal cylindrical jacket 22, with six equidistantly located flange members 23 that unite the external jacket 21 and the internal jacket 22 with each other. Longitudinal channels are limited by the flange members 23 between the external and the internal jackets, and the dimensions of these channels are adapted such that they fit exactly over the upwardly protruding guides 20 on the rails 2 and similarly over the protruding guides 15 on the lower surface of the load-bearing plate 1. The internal jacket 22 creates a space through which a locking means 5, as has been mentioned above, can be passed up through the non-circular penetrating hole 18 in the rail 2, through the internal jacket 22 and onwards through the penetrating hole 11 in the load-bearing plate.

The locking means 5, which is shown in Figure 6 and Figure 7, comprises a circular footplate 24 and a non-circular shaft 25 that stands on the footplate. Two diametrically located standing arms 26 are located at the uppermost end of the standing shaft 25, designed as an extension of a part of the walls of the non-circular part of the shaft 25. Since the standing arms 26 are relatively thin, they are also slightly flexible, which means that the outer parts of the arms 26 can be bent inwards somewhat towards each other relatively easily. Locking pegs 27 are arranged at the ends of the standing arms 26, which locking pegs protrude a small distance in the outwards direction, seen from the centre of the standing non-circular shaft 25. The locking means 5 can grip with the protruding locking pegs 27 over the edge of the penetrating hole 11 in the load-bearing plate 1, possibly interacting also with the indentations 14 if these have been created in the bottom of the circular indentation 12 in the load-bearing plate 1.

Figure 7 shows the locking means 5 standing on its footplate 24, and the drawing shows it together with a locking element 4 arranged at the uppermost part of the standing arms 26. The locking means in its operative position is introduced through the rail 2 and is surrounded by the spacer element 3, and it has the locking pegs 27 gripping the bottom of the circular indentation 12 of the load-bearing plate 1, but it is shown here for reasons of clarity separated from the parts 1, 2 and 3.

The locking element 4 is an essentially circular disk 29, designed to fit into the circular indentation 12 in the upper surface of the load-bearing plate 1. The locking element 4 has on its lower surface a downwardly facing cylindrical protrusion 28 with an external diameter that corresponds to the distance between the two standing arms 26 of the locking means 5. Thus, when the locking element 4 and the locking means 5 are mounted in a pallet, the downwardly facing cylindrical protrusion 28 protrudes in between the standing arms 26 such that these arms cannot be bent inwards: they lock not only the locking means 5 but also the rail 2 into position and in this way lock also the spacer . element 3 relative to the load-bearing plate 1. The circular disk 29 is provided at its periphery also with a pair of radially extending protrusions 30, intended to be able to fit into the vertical grooves 13 in the load-bearing plate, and that can be turned - by rotation of the circular disk when in its inserted position in the circular indentation 12 in the load- bearing plate 1 - into the undercut indentation in order to lock the locking element 4 and thus also the locking means 5 relative to other components of the pallet through the circular disk 29 demonstrating centrally on its lower surface the downwardly facing protrusion 28 that fits exactly in between the standing arms 26 of the locking means 4, such that the standing arms cannot be bent inwards towards each other, but remain locked to the load-bearing plate 1.

Indentations 31 are arranged on the upper surface of the circular disk 29 of the locking element 4, such that the disk can be gripped in order to rotate it between the locked and the unlocked positions, and in order to lift the disk from the circular indentation 12 in the load-bearing plate 1. These indentations are made clear by the perspective view in Figure 8.

The perspective view in Figure 8 thus corresponds to one of the corners of the pallet shown in its entirety in Figure 1, and the locking element 4 that with the aid of its grip indentations 31 can be rotated somewhat relative to the load- bearing plate 1 such that the radial protrusions 30 become positioned in the vertical grooves 13 and the locking element

4 can in this way be lifted up out of the circular indentation 12 in the load-bearing plate 1 is here made clear. When the locking element 4 has been removed from the load-bearing plate, the standing arms 26 of the locking means

5 can be pressed towards each other such that their locking pegs 27 can be released from the edge of the penetrating hole 11 in the circular indentation 12, and the locking means 5 can in this way be withdrawn as a unit from the lower surface of the pallet, or it can be pressed out downwards from above. In this way, either the rail 2 or the spacer element 3, or both the rail 2 and the spacer element 3, can be released from the load-bearing plate 1 in order to exchange a damaged part .

It was stated in the introduction that it is appropriate that the pallet have the same format as a EUR pallet, i.e. 800 x 1200 mm, but it is obvious that the pallet may have also other dimensions, also square dimensions.

The material as it is defined in claim 1 is plastic, and a suitable plastic is polypropene. Also other plastic materials that can provide the corresponding strength and durability can be used. Such a pallet can, of course, be given any colour that is desired, and it may be provided also with company logos if desired. The pallet according to the invention can also be provided simply with identification information, in the form, for example, of RFID tags attached onto or embedded into the pallet.

The material gives lower weight, approximately half, of the weight of a corresponding wooden pallet. The material is fully recyclable, and thus sensitive to the environment, and the pallet is hygienic since it can be cleaned, also in an autoclave .

A pallet according to the invention can, through its design, achieve a considerably longer lifetime than a wooden pallet, and will thus be economical, even though the manufacturing cost of the pallet will be higher than that of a corresponding wooden pallet.

Claims

1. A plastic pallet that comprises an upper load-bearing plate (1) supported above three parallel rails (2) that extend in a longitudinal direction of the pallet, whereby the rails (2) are located each with the aid of three spacer elements (3) at a determined distance below the load-bearing plate (1) of the pallet, characterised in that a locking means (5) is arranged from the lower surface of the rail (2) extending through a central hole in each one of the spacer elements (3) , and the locking means (5) is provided at its upper end with a pair of elastic arms (26) that extend upwards and that are provided with locking pegs (27) that protrude to the sides arranged to grip onto an upwardly facing surface of the load-bearing plate (1) , and that a locking element (4) that can be removed is arranged to be inserted in from the upper surface of the load-bearing plate (1) and protruding into the locking means (5) , whereby the locking element (4) is provided with at least one radially protruding locking peg (30) arranged to, after rotation of the locking element (4), lock this element fixed in the load- bearing plate (1) through this being provided with a corresponding indentation (13) for the locking peg (30) and in this way preventing it being possible that the locking means (5) can be released from the load-bearing plate (1) when the locking element (4) is fixed into the load-bearing plate (1) .

2 . The pallet according to claim 1, characterised in that the locking element (4) is provided with a downwards facing protrusion (28) that fits exactly between the elastic arms (26) that demonstrate a distance from each other when these and their protruding locking pegs (27) have gripped the upwards facing surface of the load-bearing plate (1) such that the locking pegs (27) cannot be released from the surface when the downwards facing protrusion (28) is located between the arms (26) at the locking means (5) that extend upwards .

3. The pallet according to claim 1 or claim 2, characterised in that the locking element (4) is designed as an essentially circular disk (29) that is seated in the locked condition in a corresponding circular indentation (12) in the upper surface of the load-bearing plate (1) such that the upper surface of the locking element (4) lies essentially plane with the upper surface of the load-bearing plate (1) .

4. The pallet according to any one of claims 1-3, characterised in that the locking element (4) is provided at its upper surface with indentations (31) that can be gripped in order to turn the locking element (4) into and out of a locked condition.

5. The pallet according to any one of the preceding claims, characterised in that the load-bearing plate (1) is provided with bevels (10) at its lower surface by the side of the spacer elements (3) at its outermost edges, which bevels extend inwards from the edge of the load-bearing plate (1) .

6. The pallet according to any one of the preceding claims, characterised in that the rails (2) are provided at their upper surfaces, at least at the side of the spacer elements (3), with bevelled edges.

7. The pallet according to claim 6, characterised in that the rails (2) demonstrate an arched upper surface (16).

8. The pallet according to any one of the preceding claims, characterised in that the load-bearing plate (1) demonstrates a number of penetrating essentially circular holes . (6) evenly distributed across the surface of the plate.

9. The pallet according to claim 8, characterised in that reinforcement webs (7) are arranged diametrically through the circular holes (6) in a region (8) perpendicular to the longitudinal direction of the pallet (1) at the spacer elements (3) .

10. The pallet according to claim 8 or 9, characterised in that reinforcement webs (7) are arranged diametrically through the circular holes (6) along the diagonals (9) of the pallet (1) .

11. The pallet according to any one of the preceding claims, characterised in that indentations (19) are arranged in the upper surface of the rails (2) , into which indentations the spacer elements (3) fit.

12. The pallet according to any one of the preceding claims, characterised in that guides (15, 20) are arranged on the lower surface of the load-bearing plate (1) and on the upper surface of the rails (2) , which guides are arranged to be inserted into longitudinal channels formed in the spacer elements (3) .