Motor vehicle with pedestrian protection structure

Abstract

In a motor vehicle with a windscreen (17), a lower edge (24) of the windscreen (17) is supported at least locally by a windscreen cross member (2), and a lateral edge (25) of the windscreen (17) is supported at least locally by an A-pillar (3). The edges (24, 25) of the windscreen (17) meet at a corner, with end regions of the edges (24, 25) at the corner extending without contact with the windscreen cross member (2) and the A-pillar (3).

Description

The present invention relates to a motor vehicle having improved provisions for pedestrian protection, in particular for protecting the head of a pedestrian when the pedestrian impacts the vehicle in a boundary region between the front windshield and the front hood in the event of an accident.EP 3 421 332 B1 discloses a motor vehicle in which a cross-member for a window pane comprises a horizontally elongate profile with a closed cross section and a sheet metal which fills a space between the profile and a front window by being fastened to the profile and bearing against the lower edge of the front window. If the structure of this sheet is designed to ensure effective protection of the pedestrian's head in the event of an impact in the middle of the lower edge of the front window, then it is to be expected that the lower edge away from the middle is not sufficiently flexible in regions which are also supported by flanking A-pillars. If, on the other hand, it is designed to provide adequate protection in the lateral regions, there is the risk that, in the event of a central impact in which the flanking support by the A-columns is absent, the head will only break down with insufficient deceleration down to the substantially less flexible horizontal profile.An object of the invention is therefore to provide a motor vehicle in which compliance appropriate for protecting the head of a pedestrian can be provided over the entire width of the front windshield.According to one aspect of the invention, the object is achieved in that, in a motor vehicle having a cross-member for the windshield which supports at least locally a lower edge of the front windshield and an A-pillar which supports at least locally a lateral edge of the front windshield, wherein the edges of the front windshield meet at one corner, end regions of the edges run at the corner without contact with the cross-member for the windshield and with the A-pillar. Thus, the cross member and the A-pillar can each be constructed in such a way that they provide the necessary strength in the event of an impact in a region of the pane which is remote from the corner and is directly supported by them, and at the same time it is possible to prevent the rigidity from becoming too high in the event of an impact close to the corner, because both support one another.In order to be able to adapt the rigidity at the corners of the windshield, a space between the end regions of the edges, the cross windshield member and the A-pillar may be filled with an element which is more easily deformable than the cross windshield member and the A-pillar.In order to avoid effects on the climate in a passenger compartment, the element should fill the intermediate space in a wind-tight manner.The element can be formed from a metal sheet, the wall thickness of which is less than that of the cross member and the A-pillar, or from a plastic.In order to achieve a uniform delay over the available deformation range, the element can have a bellows structure.The bellows structure may include a lower leg between the lower edge and the cross-member and a side leg between the side edge and the A-pillar. Edges of the bellows structure can each extend in both legs substantially parallel to the adjacent edge, wherein edges located along an imaginary cross section towards the center of the front pane alternate with edges facing away from the center. In order to achieve a uniform delay also along a bending zone between the legs, the edges can be arranged such that in the bending zone an edge of one of the legs, which edge is situated towards the center of the front pane, crosses an edge of the other leg facing away from the center.Alternatively, the flexibility of the element can also be adjusted with the aid of local perforations.According to an alternative embodiment, the element is a molded body made of foam, such as PU foam,In order that the element can efficiently absorb energy due to its deformation in the event of an impact, an edge of the element abutting the front window and an edge of the element abutting the cross-member of the front window or the A-pillar should be spaced apart in a direction perpendicular to the surface of the front window.The cross member and the A-pillar can be connected to one another in a connecting region below the corner and typically also to a strut wheel installation, which is usually oriented approximately to approach the corner of the front window. The lack of contact of the windshield with the cross-member and the A-pillar in the vicinity of the corner according to the invention also prevents the strut wheel assembly from contributing to the rigidity of the corner.The dimension of the member perpendicular to the surface of the windshield should be no less than 50 mm to provide a sufficient head impact deceleration path above a structural node where the cross-member and the A-pillar meet each other and typically the door hinge pillar and the strut meet wheel installation. Towards the free ends of the legs, the dimension perpendicular to the surface of the front pane can decrease continuously. The length of the legs should be at least 200 mm.In order to provide the clearance at the corner of the windshield, material of the cross member and the A pillar near the corner must be omitted as compared with a conventional structure. In order that the load capacity of the vehicle body is not reduced as a whole as a result, the connecting region can be designed to be locally double-walled.Further features and advantages of the invention will become apparent from the following description of exemplary embodiments with reference to the appended figures. They show FIG. 1 shows a structural node of a motor vehicle body; FIG. 2 shows a deformable element of the structural node from FIG. 1 ; FIGS. 3 a, b show sections through a lower edge region of a front window and a front window cross member of the motor vehicle body; FIGS. 4 a, b show sections through a lateral edge region of the front pane and an A-pillar; and FIG. 5 shows a variant of the deformable element.FIG. 1 shows a structural node 1 of a motor vehicle body in a perspective view from the front. At the structural node 1, a cross member 2 provided to support the lower edge of a front window, not shown in the figure, an A-pillar 3 laterally flanking the front window, a strut wheel insert 4 extending over a wheel arch, and a door hinge pillar 5 extending between the wheel arch and a door opening meet. The strut wheel insert 4 and the door hinge pillar 5 overlap at the structural node 1 as viewed from the lateral direction and form a box-like structure in that a wall section 12 of the door hinge pillar 5 parallel to the strut wheel insert 4 and overlapping it is connected via edge regions 22 and flanges 23 angled from the wall section 12.The cross member 2 and the A-pillar 3 each have, remote from the structural node 1, an elongate flange 6 and 7 respectively, which is provided as a bearing surface for the edges of the front window. In the immediate vicinity of the structural node 1, both flanges 6, 7 pass into a support surface 8 spaced apart from the front pane, and an intermediate space between the support surface 8 and the front pane is filled by an angular element 9 which is fastened to the support surface 8.The element 9 is more easily deformable than the regions of the cross member 2 and the A-pillar 3 below it. In order to achieve this deformability, a steel sheet used for the production of the element 9 can be thinner or of a more flexible quality than that of the cross member 2 and the A-pillar 3; it is also conceivable to produce the element 9 from plastic, for example as an injection-molded part or as an optionally fiber-reinforced composite laminate.The element 9 has two legs 10, 11 which extend along the cross member 2 or the A-pillar 3 and whose dimension decreases perpendicularly to the surface of the front window in each case towards the ends of the legs 10, 11. Whereas along the flanges 6, 7, far from the structural node 1, which is at most slightly resilient, the resilience of the cross member 2 and the A-pillar 3 is sufficient to meet the prescribed acceleration limit values in the event of an impact of the head of a pedestrian, this is not the case above the structural node 1; in order here to achieve the required resilience and deceleration distance, the element 9 is inserted between the front window and the structural node 1.FIG. 2 shows the element 9 in an enlarged view. The two legs 10, 11 each have a length I1, I2of at least 200 mm and a height h which continuously decreases from a maximum of approximately 70 mm in the connecting region between the legs 10, 11 toward their free ends. The legs 10, 11 have an n U-shaped cross section with an upper strap 13 resting against the front pane, a lower strap 14 resting against the support surface 8 (see FIG. 3 a ) and a wall section 15 connecting the two straps 13, 14, which are formed in one piece from sheet metal or plastic. In order to exactly adjust the flexibility of the element 9, the wall section 15 can be provided with apertures 16 in places. Alternatively, the element 9 may be formed of foam material such as PU foam material; in this case, the legs 10, 11 typically have a substantially rectangular or parallelogram-shaped cross section with sides 13, 14 abutting the support surface 8 and the front window.FIG. 3 ashows a section through a part of the front pane denoted here by 17, the flexible element 9 and the cross member 2 along a plane extending vertically and in the longitudinal direction of the vehicle body. A lower edge 24 of the front window 17 and the bearing surface 8 of the cross member 2 are spaced apart by a space which is filled by the lower limb 10 of the element 9. The lower belt 14 is directly fixed to the bearing surface 8 of the cross member 2; the lower belt 13 supports, via an intermediate glue 18, the front window 17 in the vicinity of its lower edge 24. the wall portion 15 is oriented substantially vertically in order to collapse under an impact from above.The cross section of the cross member in FIG. 3 ais substantially the same as in a sectional plane closer to the vehicle center, shown in FIG. 3 b. The flexible element 9 does not extend as far as into the sectional plane of FIG. 3 b; here, the front pane 17 is spaced apart from the cross member 2 in a conventional manner only by the adhesive bond 18.The cross member 2 yields essentially not by changing its cross section, but by bending over its length, upon an impact. Therefore, it is substantially more compliant in the vehicle center, in the plane of FIG. 3 b, than at its ends fixed to the structural nodes 1 on both sides of the vehicle body. Since in the vicinity of the structural nodes 1 in each case one element 9 instead of the cross member 2 provides the flexibility required for a head impact, the structure of the cross member 2 can be designed such that it has a flexibility adequate for effective pedestrian protection in the middle of the pane lower edge without too high a rigidity at the corners of the front pane 17 making compliance with the legal requirements impossible there.The same applies to the A-pillar 3, as shown in FIG. 4 on the basis of two sections in planes orthogonal to the longitudinal direction thereof. The sectional plane of FIG. 4 a extends near the lower edge 24 of the front pane 17 through the leg 11 of the resilient element 9, which fills a space between the inner side of the pane 17 near its lateral edge 25 and the support surface 8 of the A-pillar 3. The structure of the leg 11 with the belt 13 facing the front pane 17 and the belt 14 supported on the bearing surface 8 of the A-pillar 3 and the compressible wall section 15 connecting the belts 13, 14 ensures sufficient flexibility of the front pane 17 in the vicinity of its lower corner facing the structural node 1. Further up, beyond the end of the leg 11, the lateral edge 25 of the disc 17 is separated from the flange 7 of the A-pillar 3 only by the glue 18 as shown in Fig. 4b. However, the flexibility thereof increases as the distance from the structural node 1 increases like that of the cross member 2, so that sufficient flexibility along the lateral edge of the front window 17 can be ensured in the middle of the A-pillar 3 even without an intermediate element 9.FIG. 5 shows a variant of the resilient element 9 in a view analogous to FIG. 2, If the compressible wall section 15 of a resilient element 9 extends in the direction of the load acting in the event of a head impact, then the initial resistance of the element 9 to deformation is so high until the wall section 15 begins to escape transversely with respect to the load; as soon as this has taken place, the resistance collapses to a large extent and only increases again if the front pane 15 is situated shortly in front of the supporting surface 8. The variant of FIG. 5 achieves a more uniform resistance to deformation in that the wall sections 15 in both legs 10, 11 each have a bellows structure with wall segments 19 oriented obliquely to the loading direction. The wall segments 19 are connected to one another via edges 20, 21 which are alternately directed toward the center of the front pane 17 or away from it. In order to ensure uniform deformability even at a corner of the element 9 at which the legs 10, 11 meet one another, the wall segments 19 of the two legs can be offset with respect to one another in such a way that an edge 20 of one leg facing the center of the front pane 17 crosses an edge 21 of the other leg facing away from the center.Reference numerals denote reference numerals1 Structural node 2 Cross member 3 A-pillar 4 Strut Wheel Mounting 5 Door hinge pillar 6 Flange 7 Flange 8 Bearing surface 9 Element 10 (lower) leg 11 (lateral) leg 12 Wall section 13 Upper belt 14 Lower belt 15 Wall section 16 Aperture 17 Front pane 18 Adhesive 19 Wall segment 20 Edge 21 Edge 22 Edge region 23 Flange 24 Lower edge 25 Lateral edgeReferences included in the specificationThis list of documents cited by the applicant has been produced in an automated manner and is only included for the better information of the reader. The list is not part of the German patent application or utility model application. The DPMA does not take any adhesion for any faults or omissions.Patent Literature citedEP 3 421 332 B1

[0002]

Claims

Motor vehicle having a front window (17), a cross-member (2) supporting a lower edge (24) of the front window (17) at least locally, and an A-pillar (3) supporting a lateral edge (25) of the front window (17) at least locally, the edges (24, 25) of the front window (17) meeting at one corner, characterized in that end regions of the edges run at the corner without contact with the cross-member (2) and the A-pillar (3).Motor vehicle according to Claim 1, in which a space between the end regions of the edges (24, 25), the cross-member (2) and the A-pillar (3) is filled with an element (9) which is more easily deformable than the cross-member (2) and the A-pillar (3).Motor vehicle according to Claim 2, in which the element (9) fills the interspace in a wind-tight manner.Motor vehicle according to Claim 2 or 3, in which the element (9) is formed from a sheet metal, the wall thickness of which is less than that of the cross-member (2) and of the A-pillar (3), or from a plastics material.Motor vehicle according to one of Claims 2 to 4, in which the element (9) has a bellows structure and / or is locally broken through.Motor vehicle according to Claim 2 or 3, in which the element (9) is a foam body.Motor vehicle according to one of Claims 2 to 6, in which an edge of the element (9) which bears against the front window (17) and an edge of the element (9) which bears against the cross-member (2) or the A-pillar (3) are spaced apart in a direction which is perpendicular to the surface of the front window (17).Motor vehicle according to any one of claims 2 to 7, wherein the element (9) has a dimension in a direction perpendicular to the surface of the front window (17) of at least 50 mm and / or a dimension in the direction of the lower edge (24) of at least 200 mm and / or a dimension in the direction of the lateral edge (25) of at least 200 mm.Motor vehicle according to one of the preceding claims, in which, in a connecting region (1) below the corner, the cross-member (2) and the A-pillar (3) are connected to one another and optionally to a strut wheel installation (4) and / or a door hinge pillar (5).Motor vehicle according to claim 9, in which the connecting region (1) is locally double-walled.

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