The invention relates to an arrangement comprising a fuel container with a container body made from thermoplastic in a passenger vehicle and means for underpinning the container body on the vehicle body of the passenger vehicle in the direction of its weight.

Arrangements of this type are known in principle from the prior art, for example from EP 0 373 143 Al . EP 0 373 143 Al relates to a fuel container which is fastened with the aid of two clamping belts to the underside of a motor vehicle. In order to prevent sagging or bulging of the container bottom without a substantial loss of volume and with only a small outlay on material and assembly, said container bottom has at least one groove which is open at the bottom and extends from clamping belt to clamping belt. The profiled support which is supported with its ends on the clamping belts is inserted in a fitting manner into the groove.

EP 0 373 143 Al addresses only one of the critical properties of fuel containers made from thermoplastic, namely what is known as "sagging" when the container is completely full.

Moreover, thermoplastics have the property of plastic flow in the case of a relatively long action of pressure, in particular at elevated temperatures. Fuel containers made from thermoplastic are therefore designed as far as possible as systems which are operated in a pressureless manner. In the fuel containers which are used in hybrid vehicles, the completely pressureless operation of the fuel container is not always possible, with the result that the containers have to be pressure-resistant within certain limits. This requires complicated reinforcing measures both in the interior of the fuel container and on the container body. To this end, it is known, for example, to support the walls of the fuel container with respect to one another by way of tie rods or to stiffen the container wall.

In principle, however, one advantage of fuel containers made from thermoplastic is to be seen in the fact that said containers have a low empty weight and can be adapted easily to the spatial conditions in passenger vehicles, with the result that optimum utilization of installation space is possible with maximum volume yield . However, the abovementioned reinforcing measures qualify some of the properties which are inherent to the fuel container made from thermoplastic.

In principle, it would be technically possible, appropriate and desirable to configure fuel containers for passenger vehicles to be even lighter and at the same time more stable. In particular, weight saving is at the forefront of the construction of modern passenger vehicles.

The invention is therefore based on the object of providing an arrangement comprising a fuel container in a passenger vehicle, which arrangement makes a weight- optimized configuration of the fuel container, in particular of the container body, possible.

The object is achieved by way of an arrangement comprising a fuel container with a container body made from thermoplastic having the features of claim 1. Advantageous refinements of the invention result from the subclaims. According to one aspect of the invention, an arrangement is provided comprising a fuel container with a container body made from thermoplastic in a passenger vehicle, with means for underpinning the container body on the vehicle body of the passenger vehicle in the direction of its weight, the arrangement comprising, furthermore, means for supporting the container body counter to the direction of its weight on the vehicle body of the passenger vehicle. The invention is based on the concept of utilizing the vehicle body of the passenger vehicle to support and stabilize the container body, with the result that the container body itself can be of comparatively thin- walled and light configuration. This is completely opposed to the previous philosophy to underpin and arrange the container body on the vehicle body of the passenger vehicle in such a way that said container body can execute temperature-induced dimensional changes. That is to say, in the prior art the container body was inserted substantially loosely into the clamping belts which underpin it, bracing of the clamping belts took place exclusively against the vehicle body of the motor vehicle, and the container body was able to expand or contract depending on the ambient temperature.

It is provided according to the invention to support at least the tank crown of the container body against the vehicle body of the motor vehicle, with the result that, in particular, an expansion of the container body as a result of a rise in the internal pressure and/or temperature changes during the operation of the passenger vehicle are restricted by the vehicle body of the passenger vehicle on the side of the tank crown and by means for underpinning the container body, for example by clamping belts, on the bottom of the container body. The container body of the fuel container according to the invention which is part of the claimed holder arrangement therefore does not require any additional reinforcing elements or container wall reinforcements in the most favorable case when it is operated at least briefly under positive pressure. The container body can be configured, for example, from thermoplastic on the basis of HDPE . The container body can comprise, for example, a multiple-layer container wall with a carbon black-filled HDPE outer layer, a pure HDPE inner layer and an EVOH barrier layer. The container wall can additionally comprise at least one recycled layer or what are known as "regrind" layers. The container body can bear directly against an underbody of the vehicle body of the passenger vehicle and can be held or prestressed against the underbody of the vehicle body of the passenger vehicle, for example, by means of one or more clamping belts.

In order to prevent or to reduce solid-borne sound transmission from the fuel container to the vehicle body of the motor vehicle, a tank crown of the container body can bear against an underbody of the vehicle body of the passenger vehicle with at least one insulating material layer being positioned in between.

As has already been mentioned at the outset, the container body can be supported against the vehicle body of the passenger vehicle in a manner which is prestressed counter to the direction of its weight.

The support, in particular, of the tank crown of the container body can, but does not have to do, take place over the full area against the vehicle body of the passenger vehicle; rather, the support of the container body counter to the direction of its weight can comprise a plurality of dome-shaped or cushion-shaped supports on an underbody of the passenger vehicle. Said support serve primarily to decouple the container body acoustically from the vehicle body of the passenger vehicle. Decoupling of this type is already achieved to a certain extent by virtue of the fact that the support area is reduced in comparison with a full area support of the container body against the vehicle body of the passenger vehicle. Moreover, the dome-shaped or cushion-shaped supports can have damping properties, for example can be composed of an elastomeric material. Finally, it is thus possible to introduce solid-borne sound in a targeted manner into relatively stiff regions of the vehicle body. It is provided in one advantageous arrangement according to the invention that it comprises a cartridge or a compartment for receiving the container body. A compartment of this type can, for example, enclose the container body on three sides, the container body being underpinned in the compartment by means of clamping belts. As an alternative, it is possible to configure a cartridge in the vehicle body of the motor vehicle in such a way that it also underpins the container body. In this case, additional measures for underpinning the container body, for examples clamping belts, are unnecessary.

It is to be mentioned at this point that, in the prior art, means for underpinning container bodies are likewise called clamping belts, even if said clamping belts do not actually clamp the container body, but rather the container body is only laid into the clamping belts in arrangements according to the prior art .

The cartridge or the compartment can have at least one enclosure wall with at least one groove profile or at least one rib profile which interacts in a positively locking manner with at least one groove profile or rib profile of the container body. To this end, for example, one or more dovetail profiles of the container body and the vehicle body of the passenger vehicle which are complementary with respect to one another can be provided.

As a result, the container body can also be held against collapsing, for example in the case of a vacuum which occurs in the container interior, with the result that additional supports of the container walls in the interior of the fuel container are not required.

Since the container body is configured from thermoplastic, it is comparatively simple to shape corresponding profiles into the container wall or to mold them to the latter. If, as has already been mentioned at the outset, the arrangement comprises a compartment which encloses the container body laterally and on the top side, the container body can be underpinned with clamping belts. If the holding device comprises a cartridge, an enclosure wall of the cartridge can be provided as means for underpinning the container body. In the context of the present invention, a cartridge is a compartment which encloses the container body on at least four sides, on a maximum of five sides, and underpins the container body, whereas a compartment in the sense of the present invention does not underpin the container body, but can likewise enclose said container body on a maximum of five sides. In the latter case, the container body is inserted into the compartment from below, and in the first case the container body is pushed into the cartridge laterally.

In the following text, the invention will be explained using an exemplary embodiment which is shown in the drawings, in which: figure 1 shows a side view of a first variant of the arrangement in a passenger vehicle according to the invention, figure 2 shows a second variant of an arrangement of this type, said arrangement comprising a cartridge in the vehicle body of the passenger vehicle, figure 3 shows a third variant of the arrangement according to the invention, the container body being held in a positively locking manner in the cartridge, figure 4 shows a variant which corresponds substantially to the variant which is shown in figure 3, the container body having a groove profile and the vehicle body of the passenger vehicles having a rib profile which is complementary with respect to said groove profile, and figure 5 shows the enlarged detail V in figure 2.

The figures show the fuel container according to the invention in a greatly simplified manner. Merely the container body 1 is shown in outline; any installation parts, such as a filler pipe, are not shown. Moreover, the container body 1 is shown in a geometrically greatly simplified contour; the container body 1 can actually have a geometrically asymmetrical complex contour with a plurality of part volumes which are enclosed by it.

Figure 1 shows a simple first variant of an arrangement 2 according to the invention. The arrangement 2 comprises the container body 1, an underbody 3 of the vehicle body of a passenger vehicle and at least one clamping belt 4. The clamping belt 4 underpins the container body 1 in a known way. At the same time, the container body 1 is supported by means of the clamping belts 4 against the underbody 3 of the vehicle body of the passenger vehicle and, in the case of the exemplary embodiment according to figure 1, bears indirectly against the underbody 3 of the vehicle body of the passenger vehicle, an insulating material layer 6 being arranged between the underbody 3 and a tank crown 5 of the container body 1.

In the variant of the arrangement 2 according to figure 2, the underbody 3 of the vehicle body of the passenger vehicle comprises a cartridge 7 which encloses the container body 1 on a total of five sides. In this case, the container body 1 also bears against the end side/narrow side of the cartridge 7, which end side/narrow side is covered by the container body 1 and is not shown in the drawing. The cartridge 7 underpins the container body 1 with the lower enclosure wall 7b. An upper enclosure wall 7a of the cartridge 7 prevents any expansion upward by the container body 1.

According to the invention, the underbody 3 of the vehicle body undertakes the stabilizing of the container body 1 in the case of a dimensional change induced by a temperature increase and/or increase in the internal pressure.

In that variant of the arrangement 2 which is shown in figure 3, grooves 8 with a dovetail profile are provided in the upper enclosure wall 7a and in the lower enclosure wall 7b of the cartridge 7, into which grooves 8 ribs 9 of the container body 1 engage with a corresponding/complementary profile . This refinement has the advantage over the embodiment which is shown in figure 3 that the dimensional change of the container body in the sense of collapsing of the container walls, for example as a result of a vacuum within the fuel container, is counteracted.

That variant of the arrangement 2 which is shown in figure 4 corresponds approximately to the variant which is shown in figure 3, grooves 8 with a dovetail profile being provided in the container body 1 and ribs 9 with a dovetail profile being provided in the enclosure walls 7a, 7b of the cartridge 7.

Figure 5 shows an enlarged detail V of the arrangement according to figure 4, in which a plurality of dome- shaped supports 10 made from an elastomeric material are provided on the underbody 3 of the passenger motor vehicle, against which dome-shaped supports 10 the container body 1 is supported.

List of Designations

1 Container body

2 Arrangement

3 Underbody of the vehicle body

4 Clamping belt

5 Tank crown of the container body

6 Insulating material layer

7 Cartridge

7a Upper enclosure wall

7b Lower enclosure wall

8 Grooves

9 Ribs

10 Dome-shaped supports