The invention relates to a pallet having high dimensional stability and load-bearing capacity for storing and transporting all types of goods. The pallet is essentially made of plastic and thus has a low unladen weight. Nevertheless, the pallet has a high stability and is characterized by a high load-bearing force.
It is therefore particularly suitable for the transport and storage of very heavy or large loads.
The pallet is suitable for transporting packaged goods, but loose parts and bulk goods could also be stored and transported. In particular, the pallet is suitable within warehousing for the depositing of heavy items in high-rack warehouses.
In transport management and stock management, pallets of diverse types are currently in use. At issue here are, on the one hand, the size of the pallets and, on the other hand, the material from which the pallets are made.
In transport, for example to the retailer, wooden pallets are often used. In this context, pallets of standardized sizes have already been in use for some years.
A basic drawback of wooden pallets is, however, their high weight.
Plastics pallets have also been known for some years. Thus, in German utility model 7214376 of 17.04.1972, a rigid foam fibre pallet is described. Fundamental thereto is that this pallet consists of polyurethane or polystyrene or of another plastic. For stability and elasticity, synthetic fibres are foamed in place. A specific design is not provided.
In German utility model G 92 16 019.0 of 24.11.1992, a plastics pallet is disclosed, which essentially consists of a top plate, a base part, and with spacers therebetween. This pallet is suitable for storing and transporting goods, but calls for a certain amount of care in handling.
A drawback with the known plastics pallets is that they are expensive due to the manufacturing method. Known plastics pallets are also only to some extent suitable during the rough transport process. Due to the material characteristics of the plastic, pallets made of this are not very dimensionally stable.
There are a number of solutions to how, on the one hand, the advantages, such as low weight, of the plastics pallet can be utilized and, on the other hand, a higher dimensional stability and load-bearing capacity can be ensured.
In utility model DE 20017086, a plastics transport pallet with reinforcing cross-beam is described. Here, the pallet has been provided on its top side with at least one reinforcing cross-beam running transversely to the feet. With this solution, a pallet has been proposed for a specific application, which pallet, however, is not universally usable.
In German laid-open specification DE 19753213, a plastics pallet is disclosed which essentially consists of a pallet deck and runners. The pallet deck has chambers, into which stiffening profiles can be slid. The stiffening profiles are here subsequently inserted into specific chambers following manufacture of the pallet deck. If need be, the stiffening profiles can also be removed again from the plastics pallet. The stiffening profiles here lie parallel to the outer sides of the pallet within the pallet deck. However, the manner in which the stiffening profiles are inserted into the pallet deck allows the flexural rigidity to be increased only within narrow limits. Furthermore, covers are necessary for the chambers in which the stiffening profiles are located. This plastics pallet has been specially developed for specific hygiene requirements and is thus not intended for universal use.
In German laid-open specification DE 199 39 286, a supporting structure for a pallet is described. This relates to a structure with which plastics pallets specifically for use in high-rack warehouses can be reinforced. By virtue of the supporting structure, the pallet is intended to acquire a high load-bearing capacity and a high flexural rigidity in the longitudinal and transverse directions. For this, a rib arrangement, consisting of stiffening ribs, is used. The stiffening ribs here run both parallel and obliquely to the outer sides of the pallet. By choosing the thickness and number of the reinforcing ribs, it is possible to adapt the pallet to different requirements. A drawback with a pallet construction of this type is that the supporting structure has to be made more and more solid in order to increase the load-bearing capacity and the dimensional stability. For a very high load-bearing capacity and rigidity, the weight of the pallet is thereby increased, which in turn means that the weight advantages of the plastics pallet are lost.
The object of the invention is therefore to design a plastics pallet such that both a high load-bearing capacity and a high dimensional stability are obtained. The pallet is intended to be light in relation to its load-bearing capacity. The shape and size of the pallet is intended to correspond to the pallets normally found, so that use of the customary transport and storage aids, such as elevating-platform trucks and fork-lift trucks, is possible. Substantially higher load-bearing capacities are intended to be achievable, with the known reinforced pallets.
The pallet is intended to be universally usable and have low manufacturing costs.
The object is achieved by a pallet having the features of claim 1.
The invention is based on the following notions. To increase the load-bearing capacity and dimensional stability of plastics pallets, reinforcing elements were previously inserted into the base plate of the pallet. The reinforcing elements were inserted into the base plate both singly and as a combination of different elements. As a result of the use of the reinforcing elements within the base plate of the pallet, the structural height of the reinforcing elements was limited. In the final analysis, the whole of the force absorption and load bearing took place within the plane of the base plate.
With the invention, a solution is offered, in which reinforcing elements extend beneath the base plate of the pallet in the region of the feet and/or within the base plate of the pallet.
The pallet possesses a base plate of approximately rectangular format, a top side of the base plate for the reception of the goods to be stored or transported, and feet of a rectangular cross section which tapers from the base plate in the direction of the foot bottom side. The height of the feet is here dimensioned such that a transport means or a lifting means can be guided under the pallet.
Fundamental to reinforcing elements beneath the base plate in the region of the feet is
that the feet are arranged in rows extending parallel to the longitudinal side or end face of the base plate,
that, in the bottom side of the feet, grooves are formed, which extend in the longitudinal direction of the feet and thus also parallel to one side of the base plate,
that the grooves in the bottom sides of the feet arranged contiguously in a row are mutually aligned, and
that into the grooves foot rails can be inserted, which connect at least two adjoining feet on their bottom sides.
Further features consist in the fact that, in the bottom side of the feet, 2 grooves are respectively formed, which run parallel. Into these grooves foot rails can be inserted, which have a U-shaped cross section. The U-shaped foot rails have on their side arms spring elements, with which the stringers can be fixedly, yet detachably fastened in the feet of the pallet. It is additionally provided that the U-shaped foot rails have a reduced cross section in the region between the feet.
The top side of the base plate contains recesses, which, in their size and position, correspond to the bottom sides of the feet of the pallet. In the top side of the base plate, channels are additionally present, which run between these recesses and which correspond in their size and position to the foot rails inserted in the bottom side of the feet.
Within the base plate of the pallet, the reinforcing elements consist of longitudinal struts and transverse struts, which are connected to form a network structure. If the feet of the pallet are mutually connected by foot rails and these foot rails are connected by webs to the junction points of longitudinal struts and transverse struts, then the network structure of the reinforcing elements in the base plate of the pallet produces a three-dimensional lattice structure for the reinforcing elements. The spatial arrangement of the reinforcing elements within the pallet creates new conditions for the dimensioning of these reinforcing elements. For the production of a high load-bearing capacity and dimensional stability, it is now possible to use reinforcing elements with lower material usage. The three-dimensional structure allows the use of reinforcing elements of lower material thickness, a high dimensional stability being assured by the embedment of the reinforcing elements in the plastic of the pallet. That is to say, the three-dimensional lattice structure of the reinforcing elements takes up the loads acting upon the pallet and thus ensures a high load-bearing capacity and dimensional stability, whilst the plastic surrounding the reinforcing elements ensures the rigidity of the reinforcing elements themselves. The shaping of the reinforcing elements, particularly the design of the surfaces, ensures an intimate connection between the reinforcing elements and the surrounding plastic.
As the plastic for the base plate and the feet of the pallet, Styropor is preferably used.
The advantages of the invention consist in the fact that, as a result of the material, Styropor, which is used, it is possible to produce a light pallet which is variably usable and which, by virtue of the reinforcing elements, exhibits the necessary strength. Further details can be derived from the illustrative embodiment.
The invention is explained in greater detail below in the illustrative embodiment.
FIGS. 1 to 8 show embodiments of the pallet according to the invention, with details concerning the reinforcing elements located beneath the base plate of the pallet in the region of the feet.
FIGS. 9 to 11 show details concerning the reinforcing elements within the base plate of the pallet and formation of the three-dimensional lattice structure.
FIG. 1 shows a pallet in perspective view from above. The base plate 1 has a rectangular format, in which the corners are slightly rounded. On the bottom side 3 of the base plate are found the feet 4, with which the pallet can be deposited on a rack or else on another pallet. The feet 4 have a rectangular cross section. On top of the bottom side 3 of the base plate 1, the cross section of the feet is larger than on the standing surface below. The height of the feet and thus the free space beneath the base plate 1 is chosen to be sized such that usual transport or lifting means, for example a fork-lift truck, can be moved under it.
In the top side 2 of the base plate 1, recesses 11 are formed. The position and the extent of these recesses 11 are made such that the feet of an identical pallet can be deposited therein with their standing surfaces. Also present on the top side 2 of the base plate 1 are channels 12, which run between the recesses 11, to be precise parallel to the longitudinal side of the pallet.
FIG. 2 shows a pallet according to FIG. 1 laterally from below. As is already apparent in FIG. 1, the feet 4 are arranged in rows extending parallel to the longitudinal side or end face of the base plate 1. In the example, 3 rows of feet 4 are here present, respectively parallel to the longitudinal side of the base plate 1. In this case, 2 rows are located on the outer sides of the base plate 1, whilst the third row is located in the middle of the base plate 1. It should further be noted that the feet, which have a rectangular cross section, run with their longitudinal sides parallel to the longitudinal side of the base plate 1. Each row of feet consists of 3 feet, 1 foot on each of the end faces and one foot midway along the longitudinal side of the base plate 1.
Formed in the bottom side of the feet 5, i.e. on their standing surfaces, are grooves 7. These grooves extend in the longitudinal direction of the feet and hence parallel to the longitudinal side of the base plate 1. The position of the grooves 7 is identical on each foot, so that the grooves on the bottom side of a row of feet are mutually aligned.
Into these grooves 7, foot rails 8 can be inserted, which connect at least two adjoining feet 4 in a row of feet one to another. In FIG. 2, for each row of feet 4, a foot rail 8 is respectively provided, which extends over the entire length of a foot row. The foot rails 8 are here represented in the position before being fastened to the feet 2.
FIG. 3 shows an enlarged representation of the bottom side of a foot 4 and of a foot rail 8. As can be seen, two grooves 7 are formed in the bottom side of each foot, which grooves run parallel. Consequently, the foot rails 8 have a U-shaped cross section so as to penetrate into the grooves 7 with their side arms, for fastening purposes. On their top side, the side arms of the U-shaped foot rails 8 have spring elements 9. With the aid of these spring elements 9, the foot rails 8 can engage in the grooves 7 on the bottom sides of the feet 5. As a result of the spring action, a connection is formed between the foot rails 8 and the feet 4, which connection is sufficiently stable for the intended transport and storage processes. If so required, the stringers can also, however, be removed again.
FIG. 4 shows a pallet according to the invention with inserted stringers.
FIG. 5 represents a pallet as previously described. In contrast to FIG. 4, however, a modified foot rail 8 is used in this case. Whilst the foot rails 8, as previously described in FIGS. 2 to 4, have a cross section which is constant over their entire length, the foot rails 8 which are used here have regions of reduced cross section 10. When the foot rails 8 are inserted, the regions of reduced cross section are located in the interspace 6 between the feet 4. The advantage consists in the fact that the region of reduced cross section can be more comfortably passed over with a transport means, for example an elevating-platform truck.
As has already been mentioned, in transport and storage processes it is important that the pallets are, on the one hand, robust and, on the other hand, as light as possible. The base plate 1 and the feet 4 of the pallet according to the invention form a unit in production engineering terms and are made of the plastic, Styropor.
For the transport and storage processes, it is therefore advantageous if a mechanical protection can be attached to heavily stressed parts of the pallet. FIG. 6 shows a pallet according to the invention, having a side protection on the longitudinal side of the pallet. In the lower part of FIG. 6, the side protection is represented separately. The side protection is here a modification of a foot rail 8. Whilst, according to FIGS. 2 to 4, the foot rail 8 has a constant U-shaped cross section, according to FIG. 6 the outer side arm of the stringer extends as an extension 13 up to the top side 2 of the base plate 1. In this case, within the extension 13, in the interspace between the feet 4, openings 6 remain for passing over with transport means, analogously to the foot rail 8 according to FIG. 5.
For the protection of the feet 4 and of the base plate 1 during the rough transport process, protective caps 14 are additionally provided, which, as shown in FIG. 7, are fitted on the end faces of the pallet.
In a further embodiment of the invention, FIG. 8 shows a pallet for the transport of loose items or of bulk goods, having a side edge 15. This edge 15 on the top side of the pallet 2 encloses an area which is sized such that the feet of an identical pallet are accommodated therein.
FIG. 9 shows a pallet according to the invention having reinforcing elements within the base plate of the pallet. For the representation of the reinforcing elements, a section through the sectional plane I-I is shown in FIG. 11.
Between two feet 4 of a row, an interspace 6 is respectively present, which is suitably dimensioned to allow an elevating-platform truck or the forks of a fork-lift truck to be driven in. Alternatively, fork-lift trucks and elevating-platform trucks can also, however, reach under the pallet from the short transverse side.
FIG. 10 shows the reinforcing elements according to the invention in perspective representation, in accordance with the position in the pallet according to FIG. 9. Extending parallel to the longitudinal side of the pallet are longitudinal struts 16. Transverse struts 17 run parallel to the transverse side of the pallet. Longitudinal struts 16 and transverse struts 17 are dimensioned in their height such that they are located within the base plate 1. Here in the illustrative embodiment, three longitudinal struts 16, two in the region of each of the longitudinal sides of the pallet and the third midway between these, and three transverse struts 17, two in the region of each of the transverse sides of the pallet and the third midway between these, are present. The longitudinal struts 16 and the transverse struts 17 are connected to one another, so that a network structure is formed.
As shown by a comparison of FIG. 10 with FIG. 9, the junction points of longitudinal struts 16 and transverse struts 17 within the base plate 1 are respectively located above the feet 4. From the junction points of longitudinal struts 16 and transverse struts 17, webs 18 run perpendicular to the bottom side 5 of the feet 4. As already stated, three feet 4 are arranged in each row. The webs 18 of one row of feet 4 are connected to one another by foot rails 8. The reinforcing elements thus form a three-dimensional lattice structure consisting of longitudinal struts 16, transverse struts 17, webs 18 and foot rails 8.
FIG. 11 shows a section through a pallet according to the invention. The sectional region is indicated in FIG. 9 as a sectional plane I-I. The section through the pallet with its base plate 1 runs in the region of the feet 4. The longitudinal struts 16 and the transverse struts 17 are disposed between the top side 2 and the bottom side 3 within the base plate 1. From the junction points of longitudinal struts 16 and transverse struts 17, webs 18 run to the lower region of the feet 4. There, the webs 18 are connected to the foot rails 8, which, for their part, respectively connect the three feet 4 of a foot row to one another on their bottom side.
As the material for the longitudinal struts 16, transverse struts 17 and webs 18, steel plate, for example 0.5 mm thick, galvanized or else non-galvanized, may be used. The plate contains cutouts, here circular, the size of which can amount to 80% of the material height. Longitudinal struts 7 and transverse struts 8 have a U-shaped cross section 11.
This construction of the reinforcing elements ensures that they can be fully penetrated by the plastic of the pallet.
As can be seen in the figures, the top side 2 of the base plate is structured. The structures consist of rectangular recesses 11, which are connected to one another by channels 12. As already stated, the feet 4 have a conical cross section. That is to say, they taper from the bottom side of the base plate 3, beginning in the direction of the bottom side of the feet 5. Feet 4, respectively arranged in a row, are connected by foot rails 8. The recesses 11 and channels 12 on the top side 2 of the base plate correspond in their position and shape to the feet 4 and the foot rails 8 of a pallet. Structurally identical pallets can thus engage in one another for stacking purposes, whereby the stackability of the pallets is improved.
As shown particularly by FIGS. 5, 9 and 10, the foot rails 8 have regions of reduced cross section 10 in the interspaces 6 between the feet 4. It is thus possible to drive an elevating-platform truck easily into the interspace 6. The transition from the U-shaped profile to the region of reduced cross section 10 here has the shape of a triangle. The elevating-platform truck can hence be prevented from rubbing against the feet 4 when it is driven into the interspace 6.
- REFERENCE SYMBOL LIST
In a further embodiment of the invention, the foot rails 8 extend to the outer side of the feet 4. A stop protection for the pallet thus exists. In the event of impact load upon the pallet against the end face in the region of the feet, the force is absorbed by the foot rail. The plastics material in the region of the foot is thereby relieved of load.
- 1. base plate
- 2. top side of the base plate
- 3. bottom side of the base plate
- 4. foot
- 5. bottom side of a foot
- 6. interspace—openings for transport means
- 7. grooves
- 8. foot rail
- 9. spring elements
- 10. reduced cross section
- 11. recesses
- 12. channels
- 13. extension
- 14. protective caps
- 15. edge
- 16. longitudinal strut
- 17. transverse strut
- 18. web
- 19. U-profile
- 20. cutout
- 21. transition from the U-profile to the cross-sectional reduction