DE202005015405U1 - Palletized construction for transporting lengthy goods, has side units connected with carrier and base units, where end regions of side and base units are built in such a way that positive connection of side unit is realized with base unit - Google Patents

Abstract

The construction has two longitudinally running carrier units (3) connected with two crosswisely running base units (2). Side units (5) are connected with the carrier unit and with the base unit. An end region (5a) of the side units and the base unit are built in such a manner so that a positive connection (8) of the side units is realized with the base unit. The base unit is made up of a metal.

Description

The The invention relates to a pallet construction for the transport of goods, in particular of long goods, wherein at least two longitudinally running support elements are provided, wherein the carrier elements with at least two substantially transverse base elements are connected, wherein at least one side element is provided, vzw. a plurality of side members are provided, and wherein the side member with a carrier element and / or is connected to a socket element.

in the State of the art are very different pallet designs for the Transport of goods good known. In addition to the general "flat pallets" is the constructive Construction for Pallets or pallet constructions of long goods basically similar. Under several support elements, vzw. formed by individual boards, two are located substantially in the longitudinal direction of the pallet construction extending support elements, the vzw. as longitudinal running boards or squared timbers are formed. Vzw. at a 90 ° angle to the support elements are to the vehicle elements therefore arranged transversely extending further base elements. To one lateral limitation of the pallet construction can be achieved vzw. several side elements provided. The page elements are with along the length running support element the respective side by screws, nails and / or glue vzw. over one realized traction connected, possibly also additionally with the base element or even only the base element. This kind The construction is extremely simple to shape, because vzw. always only "smooth board surfaces" to connect are. As a connection measure become nails, Screws and / or glue used. The upper end of the pallet construction can form one or more cover elements from the top to the top placed on top side elements and attached there can.

These Type of pallet construction, preferably long pallets often for heavy goods such as. Tubes, rods, profiles of steel, wood, plastic or Aluminum used. During transport and storage of the pallets on the one hand, on the other hand, but also when loading the pallet construction with Good goods, weighs particularly heavy goods and a strong weight on the pallet construction and pushes, especially from the inside laterally outwards on the page elements. Often dissolve Here then the side elements at the junctions to the support elements and / or to the base elements, since the weight of the heavy goods, especially at the top of the page elements a corresponding strong leverage realized and on the lower end where the side elements are connected to the base or carrier elements, therefore a big one Torque acts, resulting in the tearing / breaking of the side element to lead can. Depending on the weight of the goods are of course the support elements and the carrier elements heavily loaded, which in particular by the extreme length at Long pallets (about 6 m) in relation to the width (only about 0.7 m) when lifting makes noticeable. There is therefore also the risk that the support elements and / or support elements break or damaged become. As a result, the pallet constructions known in the art are known therefore not yet optimally trained.

Of the Invention is therefore the object of the aforementioned Design and develop the pallet construction in such a way that the effective practical benefit is improved, namely that the pallet construction more stable and less prone to repairs is optimized, especially the pallet construction for heavy goods is.

The previously indicated task is now - initially - solved by that the end region of the side element and / or the base element are formed in this way is, so a form-fitting Realized connection of the side element with the base element is.

Further the above-mentioned object is achieved in that for reinforcement and / or to stabilize the pallet construction at least one reinforcing element is provided and that the reinforcing element at least with a certain portion with one of the support elements in direct contact stands.

It will be vzw. each side element with a specific shape of its end portion in the base element that vzw. a corresponding recess to the specifically formed end portion of the side member, one pushed or inserted. Due to the realized features, a pallet construction is thus created which avoids the above-mentioned disadvantages and fulfills a number of advantages. The pallet construction is very inexpensive to produce. Due to the positive connection of the side element with the base element, vzw. In addition, with a particular non-positive attachment to the support member, the stability of the side elements increases enormously, so that now also with heavy goods and large loads and a correspondingly large leverage (torque load on the lower end of the side elements), a release of the connection does not occur. This conditionally eliminates the previously necessary repairs or previously incurred thereby transport damage, which has a positive effect on the cost and on the overall life of the entire Palettenkonstruk tion. Basically, this works by the positive connection, such as a "wedge shape" at the lower end of the side element, which has a corresponding "Pedant" in the base element, the lateral load (due to the heavy goods goods laterally from the inside against the side element) so the emerging leverage or the resulting torque is counteracted by the specific design of the positive connection. Thus, for example, in a wedge-shaped connection, the respective surfaces of the side member and the base member then pressed against each other due to the leverage / torque effect. The at the vzw. additionally provided non-positive connection points, such as. On the longitudinal running support member realized fasteners such as nails, screws and / or glue are thus no longer the total leverage / moment or the lateral lateral force / shear force exposed. Furthermore, in particular at least one reinforcing element, vzw. two reinforcing elements are provided, which are arranged between the support elements and the base elements such that at least a portion of the reinforcing elements is directly in contact with one of the support elements. This has the consequence that appropriate forces on the support elements, vzw. over the entire length of the pallet construction, even from the central region of the support elements can be transferred to the support elements, which greatly increases the stability of the entire pallet construction. Such reinforcing elements can be arranged in the central region of the pallet construction as "shortened" reinforcing elements, but also extend over both sides along the entire length of the pallet construction, parallel to a carrier element Other embodiments, such as arcuately executed reinforcing elements are possible avoided by the inventive design of the pallet construction, the disadvantages described above and achieved decisive advantages.

It There are a lot of possibilities now Pallet construction according to the invention to design and develop in an advantageous manner. Therefor may first on the protection claim 1 and the protection claim 20 downstream protection claims to get expelled. The following are preferred embodiments the invention with reference to the following drawings and associated description explained in more detail. In the drawing shows:

1 a first embodiment of the pallet construction according to the invention from the front in a schematic representation,

2a and 2 B a pallet construction according to the invention in a schematic representation from the side and from above,

3a to 3d partially in a schematic enlarged representation of a pallet construction according to the invention, namely the positive connection between side member and base element in a schematic representation or several different embodiments for the positive connection in a schematic single part representation,

4a and 4b a further embodiment of the pallet construction according to the invention in a schematic representation from the side and from above,

5a and 5b a further embodiment of the pallet construction according to the invention in a schematic representation from the side and from above,

6a and 6b a further embodiment of the inventive pallet construction in a schematic representation of the side and from above,

7 a pallet construction according to the invention similar to that in 1 illustrated pallet construction with additionally provided sheet metal angles for attachment of the side parts of the base elements, and

8a and 8b the in the 7 illustrated pallet construction from the side and from above in a schematic representation.

The 1 to 8th show at least partially a pallet construction 1 for the transport of goods, in particular long goods. Consequently, the show 1 to 8th vzw. a pallet construction designed as a "long goods pallet" 1 ,

There are at least two substantially longitudinally extending support elements 3 provided, wherein the support elements 3 with at least two base elements 2 and at least two substantially transverse to the support elements 3 - extending base elements 2 are connected, but in particular also several base elements 2 are provided. Vzw. are several page elements 5 provided a lateral boundary of the pallet construction 1 realize. The page elements 5 are with the carrier element 3 and / or the base element 2 connected accordingly, which will be explained in detail below.

Based on 1 to 8th are the advantages of the pallet constructions realized here 1 clearly recognizable, in particular the pallet cons truktionen 1 stack well into each other, so store well, vzw. if the cover elements 6 not yet mounted, ie the pallet constructions shown here 1 can also be stacked nested.

Due to the trained base elements 2 is also a simple way created the pallet construction 1 For example, to lift with a forklift. The 2a and 2 B show that essentially the longitudinal support elements 3 with several transverse base elements 2 connected to each other. Laterally on the outside of the carrier element 3 or from the base element 2 extend up the side elements 5 ,

1 shows that the page elements 5 vzw. each with a cover element 6 are interconnected, leaving an interior space 1a the pallet construction 1 is trained.

The disadvantages described above are now avoided by the end region 5a of the page element 5 and / or the base element 2 is formed such that a positive connection 8th of the page element 5 with the base element 2 is realized. This is especially true in the 1 and the 3a to 3d clearly shown.

In the prior art, the side elements have so far been 5 always with the help of a mechanical connection frictionally directly with the support elements 3 connected, so that here the surfaces lie smoothly together. An alternative in the prior art has hitherto been the mechanically powerful connection of the side elements 5 with the base element 2 , so that here the surfaces are smooth on each other or together.

However, in the embodiment according to the invention, the side element is now 5 positively with the base element 2 connected, which was previously - in the state of the art - just not the case. This positive connection 8th is now vzw. designed so that forces caused by heavy goods in the interior area 1a the pallet construction 1 be created and the side from the inside then on the side panels 5 press, so that these forces can be counteracted. In other words, the effect caused by these forces may be due in part to the specific design of the positive connection 8th be compensated, so that the way of attaching the side panels 5 on the support part 3 and / or the base element 2 is improved and the side panels 5 no longer - as in the prior art - can tear off or break off to the outside. This may be described in more detail below:
First, the support elements 3 vzw. designed as a carrier squares. It is also conceivable that the support elements 3 made of metal or plastic. The same applies to the base element 2 or the base elements 2 the vzw. are also designed as squared timbers, but can also be made of metal or plastic. Well recognizable is, for example, in 2 B in that here several support elements 4 , which also vzw. are designed as floorboards, to form a floor of the pallet construction 1 be used and here on the support elements 3 corresponding along the length of the pallet construction 1 are attached. As a result, the pallet construction can 1 vzw. are made of wood, but also conceivable is the production of the pallet construction 1 made of metal and / or plastic parts, as already mentioned above.

The 1 and the 3a now shows a first embodiment of the positive connection 8th between a page element 5 and the base element 2 , The in the 3a illustrated positive connection 8th is first vzw. wedge-shaped. The base element 2 has vzw. a wedge-shaped recess and the side member 5 an engaging in the recess wedge-shaped extension. As an alternative (vice versa), the side element can also be used 5 a wedge-shaped recess and the base element 2 have a wedge-shaped extension engaging in the recess.

The 3b to 3d show alternative embodiments for the positive connection 8th for fastening the side element 5 with the base element 2 , For example. shows as another alternative the 3b a staircase and / or step-shaped positive connection 8th , The positive connections 8th are in the 3b to 3d - For the sake of simplicity - only schematically between the side member 5 and the base element 2 indicated. The base element 2 is shown partially cut off here. In the staircase and / or step-shaped positive connection 8th has the base element 2 vzw. a stepped or stepped recess and the side member 5 an engaging into the recess step-shaped and / or stepped extension (or vice versa).

The 3c shows a positive connection 8th , which is trapezoidal. Again, similar, as mentioned above, namely that the base element 2 vzw. a trapezoidal recess and the side member 5 has a trapezoidal extension engaging in the recess (or vice versa).

Finally, the shows 3d a positive connection 8th which is S-shaped. Vzw. here again has the base element 2 then an S-shaped recess and the side member 5 an engaging in the recess S-shaped Extension to (or vice versa).

Here in the 1 to 8th illustrated embodiments, the side member 5 have a separate extension, as described above, but it is also conceivable that the extension as an "integral part" of the respective end 5a of the page element 5 is formed, in other words, so the respective end of the side element 5 So the end area 5a itself is designed accordingly so that this "as a whole" can be plugged into a corresponding recess, as here in the 1 to 8th shown accordingly. This depends on the particular application.

As additional attachment of the side elements 5 with the base element 2 can the corresponding surfaces, which are now engaged vzw. be glued according to, in particular so the surfaces of the side element 5 , here on the one hand with the base element 2 on the other hand also with the carrier element 3 be in operative connection, are glued together, what in 3a is indicated schematically by "dashes".

As a further additional fastening means may in addition to the realization of a mechanical frictional connection between the side member 5 and the base element 2 and / or the carrier element 3 corresponding further fastening means, such as nails, screws or the like. Be provided here in the 3a partly also only schematically again by the "lines" to be indicated.

Due to the representation in the 1 , Especially in the enlarged view - at least partially - in the 3a may be the advantage of the embodiments of the pallet construction according to the invention 1 be particularly well explained: It is here now - in contrast to the prior art - a positive connection 8th between page element 5 and socket element 2 realized. So far in the prior art only frictional connections between the side member 5 and the carrier element 3 or the base element 2 realized. This is now through the positive connection 8th advantageously modified. It is also conceivable or recognizable that, for example, when loading the pallet construction 1 For example, with heavy steel tubes on the support elements 4 , the page elements 5 , vzw. when transported by a truck and when cornering, so when the truck passes a curve, these side elements 5 heavily loaded and here a force from the inside on the side elements 5 acts. The power is in 3a schematically indicated by the arrow A. This creates a leverage, namely in particular a torque at the lower end, ie at the end 5a the page elements 5 , The positive connection 8th is now designed so that this torque, so these forces counteracted. It is easy to recognize in the 3a to 3d shown respective positive connections 8th , Vzw. is the respective page element 5 although in addition with appropriate fasteners still with the support element 3 and / or the base element 2 attached. The formation of the positive connection 8th but has the consequence that these vzw. additional frictional connection via the fastening means, such as nails or screws is also no longer heavily stressed when the pallet construction 1 is loaded accordingly. As a result, a tearing of the fastening means, in particular the nails, screws or the like. Prevented. Vzw. are the cover elements 6 , each between two page elements 5 in the upper area of the pallet construction 1 extend, in some cases, when the pallet construction 1 is not yet loaded or can be removed. Therefore, they can not have an additional stabilizing effect, if they are not arranged, so that in a pallet construction 1 without cover elements 6 the positive connections 8th Here are crucial to tearing or "side cracking" of the side elements 5 to prevent. That's how it shows 3a a positive connection 8th between page element 5 and socket element 2 , which is wedge-shaped, wherein the "wedge" is formed so that in the base element 2 at least partially a small side wall 2 B is formed on the side element 5 From the inside acting forces can at least partially accommodate or compensate for them. Especially when stacking several pallet constructions 1 successive, so at vertical pressure, the wedge shape has an advantageous effect. In other words, the positive connection 8th must be designed in such a way that they are in the area of the positive connection 8th emerging forces here well from the base element 2 can be included. This is vzw. realized with a side surface or side wall 2 B as part of a corresponding recess in the base element 2 , This is also from the 3b to 3d only visible, because also here is the corresponding recess in the base element 2 designed so that here a corresponding side wall or side surface 2 B arises, which can compensate well for the forces described above, so that tearing off or kinking of the side member 5 (respectively in the 3a to 3b "To the left") is prevented or at least made more difficult.

As the 3b to 3c show, the positive connection 8th to further increase stability in other embodiments are formed, for example. As a step-shaped positive connection 8th with stair-shaped connector surfaces or side wall 2 B or a trapezoidal connection surface or as an S-shaped connection surface or side wall corresponding thereto 2 B , For example. can also be a stepped or step-shaped positive connection 8th , namely by the achieved here "larger connection area" also for the application of appropriate glue well be used.

The 1 to 8th additionally show a reinforcing element arranged here 7 ,

The reinforcing element 7 is to stabilize the entire pallet construction 1 arranged accordingly. Further, the disadvantages mentioned above are avoided by the fact that in particular for reinforcing the support element 4 or the support elements 4 as well as to stabilize the entire pallet construction 1 at least one reinforcing element 7 between the support element 4 or the support elements 4 and the socket elements 2 is arranged and that the reinforcing element 7 at least with a certain portion with one of the support elements 3 is in direct contact. As a result, corresponding forces, in particular on the support elements 4 be transferred directly to the support elements 3 derived what the stability of the entire pallet construction 1 increased accordingly.

The 4a and 4b show a part inside the pallet construction 1 arranged reinforcing element 7 , or two reinforcing elements 7 which are essentially in the middle of the pallet construction 1 as "shortened" reinforcing elements 7 are provided. It is now conceivable - as in the 1 and in the 3a shown - that the reinforcing elements 7 here to next - as a first alternative - parallel partially to the respective support elements 3 are arranged. It is also conceivable that - as in the 5a and 5b shown - the reinforcing elements 7 over the entire length of the pallet construction 1 extend and then in turn parallel to the support elements 3 are arranged, that is substantially the same length as the carrier elements 3 exhibit. As a further alternative, it is also possible that the reinforcing elements 7 arcuate to the support elements 3 are arranged, such as in the 6a and 6b shown, wherein the reinforcing elements 7 vzw. also over the entire length of the pallet construction 1 extend. An arcuate design of the reinforcing elements 7 is particularly useful if two mutually supporting arcuate reinforcing elements 7 are arranged, as in the 6a respectively. 6b shown, each at their ends with the support elements 3 are connected, so here only at the respective ends in direct contact with the support elements 3 stand. Of particular advantage is, if not only the side element 5 partially in a recess or in a groove of the base element 2 engages, but also the support elements 3 or the reinforcing element 7 , as in the 3a clearly shown. In the 3a is both the carrier element 3 as well as the reinforcing element 7 in a recess of the base element 2 admitted, however, is at the 1 only the carrier element 3 embedded in a recess and the reinforcing element 7 sits smoothly on the base element 2 on. This too depends on the particular application.

Vzw. are the reinforcing elements 7 also made of wood. It is also conceivable, however, a production of metal or plastic. Vzw. are the reinforcing elements 7 between the base element 2 and the support elements 4 , So arranged the support boards. Vzw. are several support elements 4 provided, but it is also conceivable that only a single support element 4 is provided, extending over the entire length of the pallet construction 1 extends. This is advantageous if "smaller goods" must be safely absorbed, so that there are no gaps between multiple support elements 4 can arise.

The 7 and 8th additionally show that the page elements 5 with the help of sheet metal angles 9 in addition to the base elements 2 are attached. Good to know he is that the sheet metal angle 9 are formed substantially L-shaped, so that here partially the underside of the base elements 2 vzw. through a leg of the sheet metal angle 9 can be engaged and the other leg of the sheet metal angle 9 here then the page element 5 vzw. again attached well. This screws and / or nails are used and it is vzw. in the base elements 2 a groove for the corresponding leg of the sheet metal angle 9 intended.

The dimensions of the pallet construction 1 may vary depending on the application and the embodiment. The dimensions of the preferred estate pallet construction 1 will be briefly explained in the following: The pallet construction 1 has essentially vzw. a total length of 6 m, a total width of about 0.7 m and a total height of about also 0.7 m. A page element 5 is preferably 710 mm long and 100 to 200 mm wide and 28 to 40 mm thick. The distance between the respective side elements 5 to the next adjacent page element 5 is - measured in the middle - essentially 1464 mm, here two opposite side elements 5 vzw. with a base element 2 are connected.

As a result, the inventive pallet construction 1 decisive improvements for the stability of the side elements 5 and the entire pallet construction 1 achieved, so that a safe transport without transport damage risk is possible.

1

pallet construction

1a

The indoor section

2

base element

2a

end

2 B

sidewall

3

support element

4

support element

5

page element

5a

end

6

cover element

7

reinforcing element

8th

positive-locking connection

9

Blechwinkel

Claims (26)

Pallet construction ( 1 ) for transporting goods, in particular long goods, wherein at least two longitudinally running carrier elements ( 3 ) are provided, wherein the support elements ( 3 ) with at least two substantially transverse base elements ( 2 ), wherein at least one page element ( 5 ) is provided, vzw. several page elements ( 5 ) are provided, and wherein the side element ( 5 ) with a carrier element ( 3 ) and / or with a base element ( 2 ), characterized in that the end region ( 5a ) of the page element ( 5 ) and / or the base element ( 2 ) is formed such that a positive connection ( 8th ) of the page element ( 5 ) with the base element ( 2 ) is realized. Pallet construction according to the preceding claim, characterized in that the carrier element ( 3 ) is made as a support edge timber or metal or plastic. Pallet construction according to one of the preceding claims, characterized in that the base element ( 2 ) is made of squared timber or of metal or plastic. Pallet construction according to one of the preceding claims, characterized in that at least one support element ( 4 ), vzw. several support elements ( 4 ) is provided for forming a floor or are. Pallet construction according to one of the preceding claims, characterized in that the pallet construction ( 1 ) made of wood, metal and / or plastic. Pallet construction according to one of the preceding claims, characterized in that the positive connection ( 8th ) for fastening the side element ( 5 ) with the base element ( 2 ) is designed as a wedge-shaped connection. Pallet construction according to one of the preceding claims, characterized in that the base element ( 2 ) a wedge-shaped recess and the side element ( 5 ) has a wedge-shaped extension engaging in the recess, or - conversely - the side element ( 5 ) a wedge-shaped recess and the base element ( 2 ) has a wedge-shaped extension engaging in the recess. Pallet construction according to one of the preceding claims, characterized in that the positive connection ( 8th ) for fastening the side element ( 5 ) with the base element ( 2 ) is designed as a staircase and / or stepped connection. Pallet construction according to one of the preceding claims, characterized in that the base element ( 2 ) a stepped or stepped recess and the side element ( 5 ) has an engaging in the recess step-shaped or stepped extension, or - conversely - the side element ( 5 ) a stepped or stepped recess and the base element ( 2 ) has an engaging in the recess step-shaped or stepped extension. Pallet construction according to one of the preceding claims, characterized in that the positive connection ( 8th ) for fastening the side element ( 5 ) with the base element ( 2 ) is designed as a trapezoidal connection. Pallet construction according to one of the preceding claims, characterized in that the base element ( 2 ) a trapezoidal recess and the side member ( 5 ) has a trapezoidal extension engaging in the recess, or - conversely - the side member 5 a trapezoidal recess and the base element ( 2 ) has an engaging in the recess trapezoidal extension. Pallet construction according to one of the preceding claims, characterized in that the positive connection ( 8th ) for fastening the side element ( 5 ) with the base element ( 2 ) is designed as an S-shaped connection. Pallet construction according to one of the preceding claims, characterized in that the base element ( 2 ) an S-shaped recess and the side element ( 5 ) one in the off having engaging S-shaped extension, or - conversely - the side element ( 5 ) an S-shaped recess and the base element ( 2 ) has an engaging in the recess S-shaped extension. Pallet construction according to one of the preceding claims, characterized in that the end region ( 5a ) of the page element ( 5 ) has a corresponding extension or the end region ( 5a ) itself is designed accordingly, namely wedge-shaped, stepped, trapezoidal or S-shaped. Pallet construction according to one of the preceding claims, characterized in that as additional fastening of the side element ( 5 ) with the base element ( 2 ) the base element ( 2 ) with the page element ( 5 ) is glued. Pallet construction according to one of the preceding claims, characterized in that for fastening the side element ( 5 ) additionally at least one mechanical frictional connection of the side element ( 5 ) with the base element ( 2 ) or with the carrier element ( 3 ) is realized. Pallet construction according to one of the preceding claims, characterized in that for fastening the side element ( 5 ) on the carrier element ( 3 ) and / or on the base element ( 2 ) Glue and / or nails and / or screws are provided. Pallet construction according to one of the preceding claims, characterized in that a plurality of side elements ( 5 ) are provided. Pallet construction according to one of the preceding claims, characterized in that the positive connection ( 8th ) is formed such that one on the side element ( 5 ) - from the inside acting force - due to the formation of the positive connection ( 8th ) is at least partially compensated, in particular a force absorbing at least partially sidewall ( 2 B ) in the base element ( 2 ) is trained. Pallet construction ( 1 ) for the transport of goods, in particular long goods, in particular according to one of claims 1 to 19, wherein at least two longitudinally running carrier elements ( 3 ) are provided, wherein the support elements ( 3 ) with at least two substantially transverse base elements ( 2 ), wherein at least one page element ( 5 ) is provided, vzw. several page elements ( 5 ) are provided, and wherein the side element ( 5 ) with a carrier element ( 3 ) and / or with a base element ( 2 ), characterized in that for reinforcement and / or stabilization of the pallet construction ( 1 ) at least one reinforcing element ( 7 ) is provided and that the reinforcing element ( 7 ) at least with a certain portion with one of the support elements ( 3 ) is in direct contact. Pallet construction according to claim 20, characterized in that two reinforcing elements ( 7 ) are provided and that the reinforcing elements ( 7 ) between the support elements ( 4 ) and the base elements ( 2 ) are arranged. Pallet construction according to one of claims 20 or 21, characterized in that the reinforcing element ( 7 ) or the reinforcing elements ( 7 ) parallel to the carrier element ( 3 ) is arranged or are. Pallet construction according to one of claims 20 to 22, characterized in that the reinforcing element ( 7 ) or the reinforcing elements ( 7 ) only in a middle area of the pallet construction ( 1 ) are arranged. Pallet construction according to one of claims 20 to 22, characterized in that the reinforcing element ( 7 ) or the reinforcing elements ( 7 ) substantially over the entire length of the pallet construction ( 1 ). Pallet construction according to one of claims 20 to 24, characterized in that for reinforcing or stabilizing the entire pallet construction ( 1 ) the reinforcing element ( 7 ) and / or the carrier element ( 3 ) in a partial region of the base element ( 2 ) are admitted. Pallet construction according to one of claims 20 or 21, characterized in that for reinforcing the support element ( 4 ) or the support elements ( 4 ) at least one reinforcing element ( 7 ) continuously arcuate to the support element ( 3 ) is arranged, vzw. two arcuate reinforcing elements ( 7 ) are provided.