GB2410238A

GB2410238A - Pallet with retractable wheels

Info

Publication number: GB2410238A
Application number: GB0401208A
Authority: GB
Inventors: Richard Hodson Bebb
Original assignee: Linpac Mouldings Ltd
Current assignee: Linpac Mouldings Ltd
Priority date: 2004-01-20
Filing date: 2004-01-20
Publication date: 2005-07-27
Also published as: GB0401208D0

Abstract

A pallet 2 includes a platform 6 and a support structure 8, 10 for supporting the platform 6 above ground. The support structure 8, 10 includes a plurality of retractable wheels 14 and a lifting mechanism 16, 20, 22 linked to the wheels 14, the lifting mechanism 16, 20, 22 being able to extend or retract the wheels 14. The pallet 2 may include an actuating element 28 which is engageable by a handling device 4 and is mechanically linked to the wheels 14. A pallet system is also disclosed which consists of one or more pallets 2 and a handling device 4 for moving the pallets 2, the handling device 4 including an actuator 48 for actuating the lifting mechanism 16, 20, 22. The pallet 2 and/or the handling device 4 may include a clamping element 32, 50 which clamps the pallet 2 to the handling device 4 or vice versa.

Description

PALLET AI\D PALLET SYSTEM The present invention relates to a pallet and to

a pallet system that includes one or more pallets and a handling device for moving the pallets.

Pallets are commonly used for example in warehouses to assist in the transportation of goods. A typical pallet consists of a low platform on which goods may be stacked. The platform is normally open on one or more sides so that the forks of a lifting truck can be inserted, allowing the palletised load to be lifted and moved.

The tines of a forklift truck are normally quite long (e.g. 18-1 OOcm) and this can sometimes make it difficult or impossible to insert or remove the fork underneath a palletised load in a confined space. Normal pallets may not therefore be suitable for use in such a situation.

it is an object of the present invention to provide a pallet and a pallet system that mitigates one or more of the aforesaid problems.

According to the present invention there is provided a pallet including a platform and a support structure for supporting the platform above the ground, the support structure including a plurality of retractable wheels and a lifting mechanism linked to the retractable wheels, the lifting mechanism being operable to extend or retract the wheels.

The provision of wheels makes it possible to move the pallet without lifting it off the floor.

It is not therefore necessary to insert the forks of a lifting truck beneath the pallet in order to move it, which makes it easier to use in confined spaces. Because the wheels are retractable when the pallet is not being moved, they do not affect the stability of a load stacked on the pallet. The lifting mechanism also ensures that when the pallet is moved, it is lifted vertically, so that the load is not tipped.

Where lack of space does not preclude the use of a forklift truck, the pallet can also be lifted and moved in a conventional manner using a forklift truck.

The lifting mechanism may include an actuating element that is engageable by a handling device, for example a trolley or cart, so that the lifting mechanism is actuated automatically whenever the handling device is engaged with the pallet. The actuating element may be S-PCS()()5 ()401 i 9 wp] 19 January 2()()4 mechanically linked to the retractable wheels. Advantageously, the actuating element is mounted adjacent a first side of the pallet and the retractable wheels are mounted adjacent an opposite second side of the pallet.

The lifting mechanism is preferably constructed and arranged such that actuation of the actuating element raises or lowers the first and second sides of the pallet substantially simultaneously, to ensure that any load stacked on the pallet is not tipped.

The pallet may include a clamping element, for example one or more openings in the first side of the pallet, for clamping the pallet to a handling device.

According to a further aspect of the invention there is provided a pallet system including one or more pallets as defined by any one of the preceding statements of invention and a handling device for moving the pallets. The handling device may for example be a trolley or hand cart.

Thehandling device may include an actuator for actuating the lifting mechanism. This may for example consist of one or more lifting arms.

The handling device preferably includes a clamping element for clamping the handling device to a pallet. For example, the handling device may include one or more clamping arms.

Certain embodiments of the present invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a side elevation of a pallet system, including a pallet (shown in side section) and a pallet trolley; Figure 2 is a rear elevation of the pallet shown in Figure 1; Figure 3 is a sectional side elevation of the pallet in a raised configuration; and Figure 4 is a sectional side elevation of a modified pallet.

A pallet system according to a first embodiment of the invention is shown in Figures 1-3.

The pallet system includes a pallet 2 and a trolley (or hand cart) 4 that can be used to move the pallet 2.

S-P55()X()5_(:\4() 1 19 wpJ 19 January 2004 The pallet 2 includes a generally square or rectangular platform 6, which is supported at its corners by four legs, comprising two front legs 8 and two rear legs 10. The platform 6 and the legs 8, 10 are hollow and house a lifting mechanism 12 for raising the pallet 2, so that it can be moved. The lifting mechanism 12 actually comprises two identical mechanisms mounted on the left and right sides of the pallet 2, only one of these mechanisms being shown in Figure I. The two lifting mechanisms may be linked to operate in unison, or they can be entirely separate.

Each lifting mechanism 12 includes a wheel 14 that is mounted on a pivoting and 16 within the rear leg 10. The pivoting and 16 comprises a pair of metal plates between which the wheel 14 is mounted. The and 16 is mounted approximately at its centre point on a pivot pin 18, the wheel 14 being located towards the lower end of the arm and the upper end of the arson extending upwards into the body of the platform 12.

The and 16 is pivotally connected at its upper end to one end of a connecting rod 20, the opposite end ofthe connecting rod being pivotally connected to a substantially vertical first arm of a bell crank 22, which is mounted on a pivot pin 24 within the *ont leg 8. A second and of the bell crank 22 extends substantially horizontally forwards towards the front wall 26 of the front leg 8. The bell crank 22 also comprises two metal plates, these plates being connected to one another at the free end of the second arm by means of a short connecting pin 28. This pin 28 lies adjacent a window 30 in the front wall 26 of the front leg 8. The pallet also includes a pair of rectangular openings 32 in the front wall 34 of the platform.

The trolley 4 is mounted on wheels 40 and castors 42 and includes an operating handle 44 that is linked to a hydraulic pump 46, a pair of lifting arms 48 and a pair of short clamping anns 50. The lifting arms 48 have a hook-shaped formation and are designed to engage the connecting pin 28 through the window 30 in the front legs 8 of the pallet.

The hydraulic pump 46 is conventional and will not be described in detail. The pump 46 may be operated by pumping the handle 44, which causes the lifting arms 48 to rise vertically upwards, or to descend back towards the floor level. The short clamping arms do not move and always remain at a fixed height above the floor, so that they are aligned with the openings 32 in the front wall of the platform. The arms 50 are slightly smaller than the openings 32, so that they can easily be inserted into the openings.

S-P55()805_04()11') wild 1') January 20()4 When the pallet 2 is standing on the floor as shown in Figure I (either with or without a stacked load), the lifting mechanism 12 is in a retracted position, the wheels 14 being accommodated entirely within the rear legs 10. The pallet is therefore supported entirely by the front and rear legs 8, 10, which provides a finm foundation for any stacked goods.

When it is necessary to move a pallet, the trolley 4 is presented to the front of the pallet as shown in Figure I and is then pushed towards the pallet so that the lifting anus 48 enter the windows 30 in the front legs 8, and the clamping anms 50 are inserted into the openings 32 in the front wall 34 of the platform 6. The hydraulic pump 46 is then operated by pumping the handle 44, which causes the lifting anms 48 to rise upwards from the ground. As they are lifted, the lifting arms 48 engage the connecting pins 28 in the bell cranks 22, thereby actuating the lifting mechanism. As shown in Figure 3, this causes the bell cranks 22 and the arms 16 to rotate clockwise, and causes the wheels 14 to rotate from the retracted position shown in Figure I to the extended position shown in Figure 3, in which the lowest parts of the wheels 14 extend beyond the lower ends of the rear legs 10. This lifts the rear edge of the pallet and, simultaneously, the front edge is lifted by the lifting anms 48, ensuring that the upper surface of the platform 6 remains horizontal.

The pallet is lifted until the clamping arms 50 engage the lower edges of the opening 32, thereby clamping the pallet to the trolley 4. The pallet can then be moved easily to a new location, the weight of the pallet and any stacked goods being supported on the pallet wheels 14 and the wheels 40 of the trolley 4. Once in the new position, the lifting mechanism can be lowered and the trolley 4 can then be disengaged from the pallet 2.

The pallet can also be lifted and moved in a conventional manner using a forklift truck, where this is not precluded by a lack of space. The tines of the fork can be inserted underneath platfonn 6 from any side of the pallet, between the legs 8, 10.

In an alternative embodiment shown in Figure 4, each bell crank 22 is provided with an additional link 54, which is connected to the end of the second arm. This additional link 54 includes a connecting pin 56, which is engaged by the lifting anm 48. This arrangement allows the pallet to be lifted exactly vertically, by compensating for the horizontal component oi movement caused by rotation of the bell crank 22.

S-PSS080S 040119 wp:l 19 January 2()04 Various modifications of the pallet system described ahovc are of course possible. For example, instead of using cranks and connecting rods, any other suitable mechanism may be employed for retracting and extending the wheels, including hydraulic systems, cables, gears and so on. Also, instead of providing retractable wheels only in the two rear legs, wheels and/or castors may be provided within all four legs, so that the weight of the pallet and any stacked load is supported entirely by the wheels of the pallet, instead of partially by the handling trolley. The pallet may also have more or fewer than four legs, and wheels and/or castors may be provided in any number of these.

The lifting mechanism may be actuated mechanically by the trolley orby an on-board drive mechanism, for example a motor. The trolley may also include other drive mechanisms: for example it may include a batterydriven motor. Instead of a hand trolley, any other king of handling device may be used, for example a motorised vehicle or truck.

S-P55()X()5 ()401 19 we'd 19 Janua'> 2()()4

Claims

1. A pallet including a platform and a support structure for supporting the platform above the ground, the support structure including a plurality of retractable wheels and a lifting mechanism linked to the retractable wheels, the lifting mechanism being operable to extend or retract the wheels.

2. A pallet according to claim 1, wherein the lifting mechanism includes an actuating element that is engageable by a handling device.

3. A pallet according to claim 2, wherein the actuating element is mechanically linked to the retractable wheels.

4. A pallet according to claim 2 or claim 3, wherein the actuating element is mounted adjacent a first side of the pallet and the retractable wheels are mounted adjacent an opposite second side of the pallet.

5. A pallet according to claim 4, wherein the lifting mechanism is constructed and arranged such that actuation of the actuating element raises or lowers the first and second sides of the pallet substantially simultaneously.

6. A pallet according to claim 4 or claim 5, wherein the pallet includes a clamping element, for clamping the pallet to a handling device.

7. A pallet system including one or more pallets as defined by any one of the preceding claims and a handling device for moving the pallets.

8. A pallet system according to claim 7, wherein the handling device includes an actuator for actuating the lifting mechanism.

9. A pallet system according to claim 7 or claim 8, wherein the handling device includes a clamping element for clamping the handling device to a pallet.

S-PS;()8()_()4()119 wp] 19 January 2004