WO2006021246A1

WO2006021246A1 - Motor vehicle with a water tank arranged below a windscreen

Info

Publication number: WO2006021246A1
Application number: PCT/EP2005/005958
Authority: WO
Inventors: Anne-Pascale Betz; Andreas Dehn; Axel Fedeler
Original assignee: Daimlerchrysler Ag
Priority date: 2004-08-26
Filing date: 2005-06-03
Publication date: 2006-03-02
Also published as: DE102004041269A1

Abstract

The invention relates to a motor vehicle (1), comprising a bonnet (3), to cover an engine bay (5), with a wall (27), arranged below the bonnet (3) in a closed position, running in the vehicle transverse or longitudinal direction and perpendicular to the bonnet surface, whereby the wall (27) comprises at least one defined exit point for a flexing during deformation of the bonnet (3) as a result of a force induced by an impact of a person. The motor vehicle (1) is characterised in that the flexibility of the wall (27) is produced by means of at least one pre-determined folding and/or breaking point formed by at least one partial wall thickness reduction.

Description

DaimlerChrysler AG

Motor vehicle with a arranged below a windscreen water tank

The invention relates to a motor vehicle according to the preamble of claim 1, a motor vehicle according to the preamble of claim 3 and a water tank for a motor vehicle according to claim 9.

In the automotive industry in the course of increasingly stringent safety regulations, there is a general need for vehicle occupants and other road users, in particular pedestrians, to be subjected to the lowest possible acceleration forces in the event of a vehicle crash, so that the corresponding risk of injury is minimized as far as possible. For the protection of pedestrians must be taken in particular to ensure that, for example in a crash-induced head impact on a hood of motor vehicles sufficient deformation in the area of the crash-induced, locally depressed hood and the underlying arranged units, for example, arranged below a windshield water tank or an air intake housing, is ensured. The forces occurring in the event of a crash may need to be absorbed by correspondingly shaped and deformable units or under the hood provided body parts or the like. From DE 699 10 529 T2 discloses a motor vehicle of the type discussed here, which has a front cover for covering a unit space, below which a water tank is arranged. This has a serving as a support / support for the front hood wall, which is provided at its free end with a seal against which the bonnet sealingly engages in the closed state. The extending in the vehicle transverse direction and in the vertical direction to the front roof flat side wall has a defined starting point for a compliance in a caused by deformation of the front hood as a result of an impact of a person force, wherein the starting point is formed by a crank (Figure 5). The crank ensures that, in the event of a frontal pressure load on the wall, for example in the event of a head impact of a pedestrian on the front hood with deformation of the same in the direction of the underlying unit space, the wall can deflect by bending in order to reduce the risk of injury. The bending of the wall, which takes place by design directly when pressurizing the wall, to facilitate a subsequent compression of the wall. The compression leads to a shortening of the wall with simultaneous Querschnittsvergrδßerung same.

From DE 101 09 663 Al a motor vehicle with an impact-damping hood is known, which is provided on its an aggregate space facing bottom with a stiffening structure, which is designed so that the hood is partially different stiff. In a child's head impact area, the stiffening structure of predetermined buckling lines is formed with the object of the so weakened bows is that Bonnet to soften in itself. Due to this configuration, however, the risk of accidental damage to the hood, for example, when supporting a fitter during maintenance work, significantly increased.

It is an object of the invention to provide a motor vehicle of the type mentioned, in which the resilient wall has increased stability.

To solve the problem, a motor vehicle with the features of claim 1 is proposed. This is characterized in that the flexibility of the wall provided below the front hood arranged in the closed position, which is oriented perpendicular or in the vertical direction to the front hood flat side, is realized by means of at least one predetermined bending point and / or predetermined breaking point formed by at least one partial wall thickness reduction is. Unlike the known motor vehicle so there is no progressive, continuous bending of the wall, which bends immediately after initiation of the compressive force. According to the invention the wall is kinked, wherein the buckling in its continuation may possibly lead to a fracture of the wall. A "buckling" is then present or is given when the over the vehicle front hood pressure force applied wall suddenly deflects laterally, which can occur before reaching the squeeze limit. In order for the wall to be able to buckle under load and not simply be compressed, it must in particular have a certain length. The decisive for the buckling ability or buckling properties of a component parameters are well known in the art, for example, from "Engineering Mechanics, Part 3 Strength of" Holzmann / Meyer / Schumpich, BG Teubner Stuttgart 1990,

7th edition, so that is not discussed here in detail.

The buckling of the wall takes place only when the force acting on the end face of the wall, caused for example by a head impact of a person on the front hood with deformation thereof in the direction of the wall, exceeds a certain adjustable by appropriate design of the wall thickness reduction limit. This means physically that initially acting on the end face of the wall or introduced force at low deformation of the front hood to a maximum, that is, a limit rises without causing the wall is bent or kinks, then at increasing deformation / deflection of the Wall, which is accompanied by the buckling of the pressure force applied wall to fall off again.

The embodiment of the invention is distinguished from known constructions by increased stability, which moreover ensures that during assembly of the motor vehicle and maintenance work in the unit room, the wall not already at a low force, for example, by supporting a person or dropping a component inadvertently is damaged. In addition, by the inventive design of the defined bendable wall, which forms a kind of abruptly resilient abutment for the bonnet, a particularly rigid or a stiffer front hood with a high stability can be used, without this - if any- to an undesirably high significant reduction of Pedestrian protection at head impact leads. The arranged below the front cover wall which is perpendicular or perpendicular to the front hood flat side, can run within the unit space in virtually any direction, so for example in the vehicle transverse direction or vehicle longitudinal direction, with each intermediate position can be readily realized without the function of the invention to affect the wall when Druckkraftbeaufschlagung.

To solve the problem, a motor vehicle with the features of claim 3 is proposed, which is characterized in that the crank, which ensures a desired compliance of the wall at a caused by deformation of the front hood as a result of an impact of a person force, not on the Wall itself is formed, as in the known motor vehicle, but on a running in the direction perpendicular to the wall wall portion.

In a preferred embodiment, it is provided that the wall is connected to a running in the direction perpendicular to this wall portion, which is supported only in a lying outside the direction of action of the force exerted on the wall area by means of an abutment. The resilience of the wall is thus achieved by the possibility of evading / deflecting the same in the direction of the roadway, so that the wall itself can be made rigid.

Advantageous embodiments of the motor vehicles described above will become apparent from combinations of the features resulting from the drawings, the description of the figures and the subclaims. The subject of the invention also relates to a water tank for motor vehicles according to claim 9.

The invention will be explained in more detail below with reference to the drawings. These show:

Fig. 1 in a schematic representation of a

Longitudinal section through a motor vehicle front area;

2A to 2C each show a view of a first

Embodiment of a arranged below a front cover wall;

Fig. 3 is a view of a second

Embodiment of the wall;

4A to 4C are each a view of a third

Embodiment of the wall and

Fig. 5 is a view of a fourth

Embodiment of the wall.

Figure 1 shows a schematic diagram of an embodiment of a motor vehicle 1 in the front region in a longitudinal section. Evident is a arranged in the closed position front hood 3, which serves to cover an underlying unit space 5. Below the vehicle front / windshield 7 near the edge region 9 of the front hood 3, a multi-part water tank 11 is provided, which extends in a known manner, at least over part of the vehicle width. The arranged below the windscreen 7 water tank 11 is used for collection and discharge of the windshield 7 running off or wiped liquid.

The water tank 11 has a in this embodiment made of sheet metal first part 13, in particular housing part, of which in the illustration of Figure 1, only one perpendicular to an imaginary horizontal wall 15 with formed on the front hood free end flange 17 can be seen. At the first water box part 13, a second water box part 19, in particular cover part, placed, which consists in this embodiment of plastic and is integrally formed. The second water box part 19 forms a cover for the water tank 11 and the first water box part 13 and has a first, substantially parallel to the bonnet flat side extending bottom wall 21, at its one edge region on the windscreen 7 and at its opposite edge region with the first water box part 13th concludes. Near the free edge region of the front hood 3 is from the bottom wall 21 from a water-repellent wall 23, between the free end and the front hood 7, there is a gap through which an integrated in this embodiment in the water tank 11 suction system (not shown) sucks air, as with an arrow 25 indicated.

At the end remote from the windshield 7, the second water box part 19 has a wall 27 extending in the vehicle transverse direction and substantially perpendicular to the front hood flat side, at the end of which a seal 29 is provided, which sealingly abuts against its inner surface 31 when the bonnet 3 is closed. The seal 29 may be formed as a separate part and attached to the wall 27 or in otherwise attached to it. Alternatively, it is possible to inject the seal 29 against the wall 27.

The second water box part 19 has in the transition region between the bottom wall 21 and the wall 27 still a wall portion 33 which rests in the assembled state on the flange 17 of the first water box part 13 and is preferably attached thereto. As can be seen from Figure 1, the wall portion 33 only a partial overlap with the underlying flange 17, that is so in the vertical direction is not supported in sections, which will be discussed in more detail below.

FIG. 2A shows a section of the second water box part 19 in the region of the wall 27 in a mirrored view. The seal 29 is not shown. It can be seen that the wall 27 has no constant thickness, but here in its center has a region 35 with reduced thickness. By this wall thickness reduction, a desired kink is formed, the starting point of a buckling of the wall 27 at Druckkraftbeaufschlagung due to a local denting of the front hood 3, for example in a head impact is. The pressure / compression force F, which is introduced in the region of the end face 37 of the wall 27 in this, is indicated by an arrow.

The wall portion 33 has in this embodiment, only a partial overlap with serving as abutment flange 17, that is, the wall portion 33 is about the dimension x over the edge of the flange 17, whereby a certain flexibility of the wall 27 is achieved by Bending of the wall portion 33 is achieved over the edge of the flange 17. As can be seen from FIG. 2A, the wall 27 is slightly inclined, but substantially still in the direction perpendicular to the wall portion 33rd

FIG. 2B shows a perspective view of the exemplary embodiment according to FIG. 2A in the unloaded state, while FIG. 2C shows the embodiment according to FIGS. 2A and 2B with deformed wall 27 which, after a pressure force application in the region of its end face 37, is due to a crash-induced indentation of the front hood 3 in the direction of the aggregate space 5 is bent in the wall thickness-reduced region 35, is shown. It can also be seen that in addition to the buckling of the wall 27, which in itself already leads to a reduction of the loads on the front hood 3 open person, in addition the wall portion 33 with the quasi-springing from this wall 27 due to the supernatant x of the wall portion 33rd Dodge over the flange 17 in the direction of the unit space 5 by the over the edge 39 of the flange 17 projecting portion of the wall portion 33 is bent downwards away. This compliance by bending alone may be sufficient to reduce the stresses on the person to a desired level.

In another embodiment, not shown in the figures, it is therefore provided that the resilience of the wall 27 is realized exclusively by the partial projection x of the wall portion 33 via the serving as abutment flange 17. In other words, the wall 27 then has no wall thickness-reduced portion 35, as described above, but rather is so stiff that a buckling of the same, at least in the initial stage of the loads, so at the beginning of the impact of the person on the front hood 3, excluded can be. In a further embodiment, not shown, the wall portion 33 has no partial projection x with the flange 17, but is in complete coverage with this. The resilience of the wall 27 is realized here exclusively on the provided on the wall 27, wall thickness-reduced portion 35 which ensures a targeted buckling of the wall 27 when exceeding a certain maximum load.

FIG. 3 shows a further exemplary embodiment, which differs from the exemplary embodiment described with reference to the preceding figures in that the wall 27 does not have a wall thickness-reduced region 35, but rather has a constant thickness substantially over its entire length. Furthermore, the wall section 33 has a crank 41, by means of which, even with a complete covering of the wall section 33 with the underlying flange 17, as indicated in FIG. 3, a bending of the wall section 33 and thus a compliance of the wall 27 in the direction of the unit space 5 is realized.

The exemplary embodiment illustrated in FIGS. 4A to 4C differs from the exemplary embodiment according to FIG. 3 only in that, for additional flexibility, the wall 27 has the wall thickness-reduced region 35 for forming the predetermined bending point and / or predetermined breaking point. In Figures 4A and 4B, the wall 27 is shown in the unloaded state and in Figure 4C in the buckled state. It can also be seen in FIG. 4C that the wall section 33 arranged in complete coverage with the flange 17, viewed in the direction of action of the force F, is bent down to a certain extent in spite of the complete overlap in the area of the crank 41 is, whereby an extended compliance of the wall 27 is realized. The degree of bending of the wall portion 33 is limited by acting as a stop for the wall portion 33 flange 17.

FIG. 5 shows a fourth exemplary embodiment, which differs from the exemplary embodiment described with reference to FIGS. 4A to 4C in that the wall thickness-reduced region 35 of the wall 27 is arranged eccentrically, namely near the transition region between wall 27 and wall section 33. Other arrangement variants are possible.

It should be noted that the shape and size and positioning of the wall thickness reduced portion 35 of the wall 27, if provided, can be adapted to the desired compliance of the wall 27.

In a preferred embodiment, it is provided that the resilience of the wall 27 is selected so that at least after the buckling thereof and / or the deflection in the region of the crank 41 or of the edge region 39 about 10 millimeters distance can be achieved.

Particularly preferred is an embodiment in which the wall has a predetermined bending point forming wall thickness-reduced portion 35 and the wall portion 33 is disposed either in partial overlap with the flange 17 and / or has a crank 41, and is designed so that during head impact on the front hood 3 in the initial phase of deformation, the buckling of the wall 27 in the region of its desired kink, if any, and the bending of the wall portion 33 over the Edge region 33 and / or take place simultaneously in the region of the crank 41.

In the embodiments described with reference to FIGS. 2A to 5, a toggle flange is realized on account of the structural design of the wall 27 or the wall section 33, optionally in combination with the described partial covering of the wall section 33 with the flange 17 / the abutment and / or optionally in combination ,

Claims

DaimlerChrysler AGPatent claims

1. Motor vehicle (1) having a front hood (3) for covering a unit space (5) and with a wall (27), which is below the front hood arranged in the closed position

(3) is arranged and which extends in a direction perpendicular to the bonnet flat side, wherein the wall has at least one defined starting point for a compliance in a caused by deformation of the front hood (3) as a result of an impact of a person force, characterized in that the flexibility of the Wall (27) by means of at least one, by at least a partial

Wall thickness reduction formed desired kink and / or breakpoint is realized.

2. Motor vehicle claim 1, characterized in that the wall thickness reduction is arranged substantially in the middle between the force application point of the front hood (3) on the wall (27) and an abutment of the wall (27).

3. Motor vehicle (1), in particular according to claim 1 or 2, with a front hood (3) for covering a Aggregate space (5) and with a wall (27) which is arranged below the closed cover in the front hood (3) and which extends in the direction perpendicular to the front hood flat side, wherein at least one defined starting point for a compliance of the wall (27) at a deformation the front hood (3) is provided as a result of an impact of a person caused force, this starting point is formed by a crank (41), characterized in that the crank (41) on a in a direction perpendicular to the wall (27) extending wall portion ( 33) is provided.

4. Motor vehicle (1) according to one of claims 1 to 3, characterized in that the wall (27) is connected to a running in the direction perpendicular to this wall portion (33), which only in an outside of the effective direction of the wall ( 27) applied force lying area is supported by means of an abutment.

5. Motor vehicle according to claim 3 or 4, characterized in that the wall (27) of the - preferably serving as a mounting flange wall portion (33) springs.

6. Motor vehicle according to one of claims 1 to 5, characterized in that at the free end of the wall (27) cooperating with a closed front hood (3) with the inner Bonnet flat side seal (29) is provided, which molded to the wall (27) or is formed thereon.

7. Motor vehicle according to one of claims 1 to 6, characterized in that the wall (27) consists of plastic material.

8. Motor vehicle according to one of claims 1 to 7, characterized in that the wall (27) is part of a below the vehicle windshield (7) arranged water tank (11).

9. water tank (11) for a motor vehicle with a wall

(27) according to one of claims 1 to 8 and / or a crank (41) according to claim 3.