MOTOR VEHICLE

Description

[0001] The present invention relates to a motor vehicle with a fuel tank assembly for it. In particular, tanks for pressurized fuel are difficult to accommodate in a vehicle, since, on the one hand, high requirements must be met for protection against damage in an accident, and on the other hand, the high internal pressure necessitates a compact tank design, and the shape of the tank can only be adapted to existing, unused cavities in the vehicle to a very limited extent.

[0002] DE 10 2007 046 059 A1 discloses a fuel tank assembly for a motor vehicle in which the tank, in order to achieve high pressure resistance at low weight, is formed as a layered structure of composite material. To prevent damage to the layered structure by fasteners, the struts required for securing the assembly in the vehicle are embedded between layers of the composite material. However, if the struts are subjected to a compressive force in an accident, this force is transmitted to the tank essentially undamped. The fuel tank assembly is therefore only able to resist accident-induced deformation to a limited extent, and there is a high risk that deformation will lead to damage to the tank.

[0003] Further prior art includes JP 2019-001231 and EP 3 539811 A1.

[0004] One object of the present invention is to provide a motor vehicle with a tank assembly in which the risk of damage to the tank in an accident is reduced.

[0005] According to one embodiment of the invention, the problem is solved by providing a fuel tank assembly for a motor vehicle comprising a number of transverse struts and a number of longitudinal struts for attaching at least one tank to the motor vehicle, the struts being connected to one another to form a frame shaped to hold the tank securely. This frame allows deformation forces in the event of an accident to be directed around the tank, thus protecting it from excessive stress; simultaneously, the frame stabilizes a compartment within the vehicle in which the vehicle and the tank are housed, thereby reducing the risk of damage to the tank from external foreign objects.

[0006] According to the invention, at least one tank is a component of the assembly.

[0007] According to the invention, the tank is a pressure vessel that is elongated and cylindrical in shape.

[0008] Such a tank assembly can be mounted on the underside of the vehicle body in a manner known per se; in particular, the installation space can be a recess between longitudinal members of the body.

[0009] The cross braces extend above the tank and encompass two end faces oriented perpendicular to their longitudinal direction. In the event of a collision, the cross braces can brace the longitudinal member facing the point of impact against the other longitudinal member from a lateral direction, thus counteracting a narrowing of the recess.

[0010] A cross brace can be an extruded profile or one formed by bending flat material, particularly sheet steel. To stabilize the edges of such a profile facing the longitudinal beams in the event of a collision and to enable large-area support of the longitudinal beams, the end faces are preferably formed by end plates attached to the profile, particularly welded on.

[0011] A gap may be left between the ends of the cross brace and the longitudinal beams, firstly to ensure trouble-free insertion of the tank assembly between the longitudinal beams, and secondly to prevent the ends of the brace from rubbing against the longitudinal beams when they move relative to each other during operation.

[0012] The first cross brace also features a mounting tab projecting beyond the lower edge of each end face, which serves to fix it to the underside of a longitudinal beam. The tab can be formed from flat material in one piece together with the end plate.

[0013] The end plate can also be formed in one piece with lateral tabs that are folded back to lie against the flanks of the profile and allow welding there.

[0014] According to the invention, the longitudinal struts mentioned above form a trough as part of the framework, which accommodates the at least one tank.

[0015] The cross braces can extend across the tank from one side of the hull to the other.

[0016] According to the invention, when the fuel tank assembly is installed in a motor vehicle, the cross members lie between its longitudinal members and can counteract a coming closer together of the longitudinal members and a resulting compression of the passenger compartment and the space available for the tank in the event of a side impact.

[0017] The cross braces can be anchored to two of the longitudinal braces that form the lateral flanks of the tub.

[0018] The lateral flanks or the longitudinal struts forming them can each have a profile section that is located a short distance from the undersides of the longitudinal beams, thus forming a gap that accommodates the fastening tab.

[0019] To keep the mounting bracket immobile along the length of the gap, the longitudinal strut can be connected to the longitudinal beam by pins that cross the gap. Such a pin can be a screw or a rivet. It can extend through a hole in the mounting bracket.

[0020] Further features and advantages of the invention will become apparent from the following description of exemplary embodiments with reference to the accompanying figures. These show: Fig. 1 a perspective view of a fuel tank assembly; Fig. 2 a top view of the fuel tank assembly without tanks; and Fig. 3 a section through a longitudinal beam and parts of the fuel tank assembly attached to it.

[0021] Fig. 1 and 2Figure 1 shows a fuel tank assembly according to the invention in a perspective view from an oblique angle above and a top view. The fuel tank assembly comprises at least one, here several, elongated cylindrical tanks 1 arranged parallel to one another with domed ends, each of which has an inlet / outlet connection 2. The tanks 1 are received in a basin 3. Lateral flanks 4 of the basin 3 can be formed in one piece from sheet steel, e.g. as rolled profiles. Here, however, they each comprise an upper profile 5, a lower profile 6 and a wall plate 7 connecting the profiles 5, 6. The profiles 5, 6 are each designed as hollow profiles, in particular square hollow profiles, to which edges of the wall plate 7 are welded. Due to the multi-part construction, it is possible to form stiffening ribs 8 in the wall plate 7, which extend from one profile 5, 6 to the other.

[0022] The lower hollow profiles 6 are connected to form a framework by cross braces 9, two of which are visible at the front and rear ends of the hull 3. Further cross braces could be concealed beneath the tanks 1; however, this is not the case here, as the tanks 1 extend downwards to the level of the lower hollow profiles 6. Longitudinal braces 10 run between the tanks 1 at the same level as the lower hollow profiles 6 and connect the cross braces 9 to each other.

[0023] The lateral flanks 4 bear weld pins 11 distributed along their upper surface, which, as will be explained in more detail later, are intended for fastening the fuel tank assembly to longitudinal members of a vehicle body. At least some of these weld pins 11 extend through holes 12 in fastening lugs 13 of cross members 14.

[0024] The cross members 14 each comprise an elongated, roll-formed or extruded profile element 15, preferably a square hollow profile, and two end elements attached, in particular welded, to the ends of each profile element 15. The end elements are bent from originally T-shaped flat material, with a core area of ​​the T positioned in front of the end of the profile element 15 to form an end plate 16, arms 17 of the T projecting from the core area bent back to be attached to side walls of the profile element 15, and a leg of the T provided with the hole 12 pre-bent to form the fastening tab 13.

[0025] Those cross braces 14 whose fastening tabs 13 are penetrated by a welding pin 11 are fixed in the longitudinal and transverse directions relative to the tub 3. In the embodiment shown, this is not the case for all cross braces 14; these are fixed by being connected to the penetrated cross braces via longitudinal braces 18.

[0026] The density at which the cross braces 14 are distributed along the tub 3 can vary; in the case shown here, their density is highest in a central section 19 of the fuel tank assembly, which is intended to be arranged under the seats of the motor vehicle body in order to stiffen it, in particular at the level of the torso of the driver and passenger.

[0027] Fig. 3Figure 1 shows a cross-section through one of two longitudinal members 20 of the vehicle body and an edge area of ​​the fuel tank assembly at the level of one of the welding pins 11. The fastening tab 13 pierced by the welding pin 11 is also shown in section, while other parts of the associated end element and the associated profile element 15 are shown in a front or rear view with respect to the longitudinal direction of the vehicle body.

[0028] The longitudinal member 20 is formed by a hat profile closed on the upper side by a body floor plate 21. The underside 22 of the hat profile is doubled to ensure that the load-bearing capacity of the longitudinal member 20 is not impaired by welding on the welding pin 11.

[0029] The welding pin 11 is tubular and crosses the upper hollow profile 5, allowing a welding tool to be inserted into the interior of the welding pin 11 through its open lower end. This ensures accessibility to the welding point along the entire circumference of the welding pin 11.

[0030] The mounting bracket 13 is welded to the top surface of the upper hollow profile 5. The end plate 16, which is integrally connected to the mounting bracket 13 via a bending zone 23, lies opposite a side wall 24 of the longitudinal beam 20 at a small but not negligible distance. Taking manufacturing tolerances into account, this distance is dimensioned such that the cross braces 14 can be inserted between the opposing side walls 24 of the longitudinal beams 20 without clamping. The width of the gap 25 between the cross brace 14 and the longitudinal beam 20 is preferably between 2 and 10 mm, typically approximately 5 mm.

[0031] A bevel 26 can be angled at an upper edge of the end plate to facilitate the insertion of the cross braces 14 between the longitudinal beams 20.

[0032] In the event of a lateral collision, the longitudinal member 20 adjacent to the collision zone is deflected towards the center of the body. This initially closes the gap 25 between it and the transverse members 14; subsequently, the opposite gap also closes, and the longitudinal member 20 facing away from the collision zone also contributes to the deformation resistance of the body.

[0033] A connection 27 between the upper hollow profile 5 and the wall plate 7 can be designed to be weaker than the one between the upper hollow profile 5 and the longitudinal beam 20, so that it may fail in the event of a collision and allow the framework of lower hollow profiles 6 and struts 9, 10 and the tanks 1 resting on it to move downwards. Reference sign

[0034] 1 Tank 2 Inlet / Outlet Connection 3 Tub 4 Side Flank 5 Upper Hollow Profile 6 Lower Hollow Profile 7 Wall Plate 8 Stiffening Rib 9 Cross Strut 10 Longitudinal Strut 11 Weld Pin 12 Hole 13 Mounting Bracket 14 Cross Strut 15 Profile Element 16 End Plate 17 Arm 18 Longitudinal Strut 19 Middle Section 20 Longitudinal Beam 21 Body Floor Plate 22 Underside 23 Bending Zone 24 Side Wall 25 Gap 26 Slope 27 Connection

Claims

1. Motor vehicle with two longitudinal members (20) and a fuel tank assembly engaging in a space between the longitudinal members (20), wherein the fuel tank assembly has a number of transverse members (14) and a number of longitudinal members (10) for attaching at least one tank (1) to the motor vehicle, and the transverse members (14) are located between its longitudinal members (20), wherein the tank (1) is designed as a pressure vessel, and wherein the transverse members (14) and longitudinal members (10) are connected to one another to form a frame for capturing the at least one tank (1), and wherein the fuel tank assembly further comprises the tank (1) captured by the frame, characterized in that the transverse members (14) extend above the tank (1) and have two end faces oriented perpendicular to their longitudinal direction, and wherein the transverse members (14) have a mounting tab (13) projecting beyond the end face on a lower edge of each end face, and wherein the mounting tabs (13) are attached to undersides (22) the longitudinal members (20) are fixed.

2. Motor vehicle according to claim 1, in which the cross members (14) comprise an extruded profile (15) or a profile formed by bending flat material, and the end faces are formed by an end plate (16) attached to the profile (15).

3. Motor vehicle according to any one of the preceding claims, in which the frame of the fuel tank assembly comprises a trough (3) formed by the longitudinal members (10) and accommodating the at least one tank (1), and at least one cross member (14) extends across the tank (1) from one side of the trough (3) to the other.

4. Motor vehicle according to any one of the preceding claims, in which the cross members (14) extend at the level of the longitudinal members (20).

5. Motor vehicle according to any one of the preceding claims, in which a gap (25) is maintained between the ends of the cross member (14) and the longitudinal members (20).

6. Motor vehicle according to claim 2, wherein the end plates (16) are opposite side walls (24) of the longitudinal members (20).

7. Motor vehicle according to claim 3, wherein lateral flanks (4) of the tub (3) are fixed to the longitudinal members (20).

8. Motor vehicle according to claim 7, wherein the fastening tabs (13) are arranged between the undersides (22) of the longitudinal members (20) and the lateral flanks (4) of the tub (3) and are fixed by pins (11) that connect the longitudinal members (20) to the flanks (4).

9. Motor vehicle according to claim 8, wherein the pins (11) are hollow and welded to the undersides (22) of the longitudinal members (20).