GB2343419A

GB2343419A - Bonnet assembly for a motor vehicle

Info

Publication number: GB2343419A
Application number: GB9923506A
Authority: GB
Inventors: David Henry Heaton
Original assignee: MG Rover Group Ltd
Current assignee: MG Rover Group Ltd
Priority date: 1998-11-06
Filing date: 1999-10-06
Publication date: 2000-05-10
Anticipated expiration: 2019-10-06
Also published as: GB9923506D0; GB9824299D0; GB2343419B

Abstract

A bonnet assembly for absorbing the impact of, and reducing injuries to, a pedestrian comprises an outer panel (12) and a profile member (14) extending along at least part of one edge of the outer panel, the profile member comprising a first flange (18) at one end of the member (14) and a second flange (20) at another end of the member (14). At least one step portion (22) of the profile member (14) is located between the first flange (18) and the second flange (20), the first flange (18) being connected to at least one edge of the outer panel. The step portion (22) is adapted to be collapsible in a controlled manner in the event of a collision with a pedestrian.

Description

Bonnet Assemblv for a Motor Vehicle The present invention relates to a bonnet assembly for a motor vehicle and in particular for a profile member for use in the construction of a bonnet for a motor vehicle.

Collisions between pedestrians and moving automotive vehicles are often fatal. Even at low speeds serious injury may be caused to a pedestrian involved in such a collision. The use of the term"pedestrian"will be understood also to include cyclists and the like who will impact directly onto a vehicle exterior in the event of a collision. In order to reduce such injuries, or at least the seriousness of these injuries, there has been a move in recent years to improve the manner in n which vehicles are constructed to absorb such impacts.

In particular the construction of bonnets for motor vehicles has been subject to development. It will be appreciated that the bonnet while absorbing the impact has only a limited opportunity to absorb the impact in the event of a collision with a pedestrian because of the presence of the engine block beneath the bonnet. If the impact is not absorbed sufficiently quickly, the pedestrian will become injured upon the engine block.

It is an advantage of the present invention that it reduces the likelihood of injury to a pedestrian in the event of a collision by providing a bonnet assembly for a motor vehicle having improved pedestrian impact properties.

According to a first aspect of the present invention a bonnet assembly for a motor vehicle comprises an outer panel and a profile member extending along at least part of at least one edge of the outer panel, the profile member comprising first and second flanges at either end of the profile member between which is located at least one step portion, the first flange being connected to the at least one edge of the outer panel.

Preferably, the first flange is retained within a lapped edge forming part of the at least one edge. Alternatively, the first flange may be connected to the outer panel by any suitable means.

Preferably, the second flange runs substantially parallel to a region of the outer panel to which it is adjacent.

According to a second aspect of the present invention a profile member for location at at least one edge of a motor vehicle bonnet comprises first and second flanges at either end of the profile member between which is located at least one step portion.

Preferably, the profile member has two stepped portions.

The invention will now be described by way of example only with reference to the accompanying drawings, in which: Figure 1 shows in side section a portion of a bonnet assembly according to the present invention.

Referring to the drawing there may be seen a bonnet assembly 10 for a motor vehicle. The bonnet assembly 10 comprises an outer panel 12 and a profile member 14. The outer panel may be formed from steel, aluminium or any other suitable material. The profile member 14 may conveniently be formed from steel, aluminium or any other suitable material.

In the illustrated embodiment, the profile member 14 extends along a front edge 16 of the outer panel. The profile member 14 comprises first and second flanges 18,20 at either end of the profile member. First and second step portions 22,24 are located between the first and second flanges. The first flange 18 is connected to the front edge 16 of the outer panel by being retained within a lapped region 26 of the front edge. The second flange 20 runs substantially parallel to a region of the outer panel 12 to which the second flange is adjacent. The presence of a gap between the second flange 20 and the outer panel 12 allows for slight deflections of the outer panel without affecting the profile member 14.

A cross beam 30 forming part of the motor vehicle body is shown in the Figure. The motor vehicle body surrounds a periphery of the bonnet assembly and provides support for the edges of the bonnet assembly. A seal 32 (shown in ghost in an unstressed condition) is provided along the cross beam to provide sealing means to prevent dirt and other debris from passing between the front edge of the bonnet assembly and the vehicle body.

The first step portion 22 comprises a generally horizontal part 34 and a generally vertical part 36. The generally horizontal part rests on the seal provided on the vehicle body. The generally vertical part 36 connects the generally horizontal part 34 to the second flange 20.

The second step portion 24 also comprises a generally horizontal part 38 and a generally vertical part 40. The generally horizontal part 40 connects the first flange 18 to the generally horizontal part 34 of the second step portion. The generally vertical part 38 of the second step portion connects the generally horizontal part 34 of the first step portion to the generally horizontal part 40 of the second step portion.

The first and second step portions 22,24 and the outer panel 12 define a lower region 42 and an upper region 44. The lower region 42 is defined by the second step portion 24 and the outer panel 12. The lower region is suitable for accommodating a locking catch, other latch mechanisms and/or a manufacturer's badge (not shown). The upper region 44 is defined by the first step portion 22 and the outer panel 12. The upper region provides a space into which the generally vertical part 36 of the first step portion may deflect or collapse.

A pedestrian impact, in general, comes from above and to the front of the bonnet assembly. Since the second flange 20 is not connected to the outer panel 12, it does not form a closed section which would be likely to form a brace and so not absorb the pedestrian impact. Instead, on impact in the disclosed structure the outer panel 12 will first deflect into the second flange 20. The generally vertical part 36 of the first step portion will tend to act as a brace to support the outer panel. However, because the second flange 36 is not connected to the outer panel the generally vertical part of the first step portion is free to bend about a point 46 at which it joins the generally horizontal part 34 of the first step portion. This bending absorbs some of the energy associated with pedestrian impact.

If the profile member becomes trapped between the cross beam 30 of the motor vehicle body and the outer panel 12 the section of the generally vertical part may itself be such that it provides for a controlled collapse of the generally vertical part 36.

This may be achieved by forming the upper generally vertical part 34 of varying height along a length of the profile member 14. For example, the upper generally vertical part may be formed as a series of pyramidal portions (not shown). In such a case, the profile presents the second flange 20 to the outer panel 12 only intermittently along the length of the profile at regions corresponding to the peaks of the pyramidal portions.

In the event of an impact such that the vertical part is caused to deflect or collapse, the upper regions of the pyramidal portions will collapse before any base regions of the pyramidal portions. In a low impact collision only the upper parts of the pyramidal portions will be collapsed. In a high impact collision all of the layers of the pyramidal portions will be collapsed. The provision of such pyramidal portions will result in a controlled collapse of the bonnet assembly in the event of a pedestrian impact.

Where the construction of the bonnet assembly allows, the profile member 14 may be provided on more than one edge of the bonnet assembly.

It will be understood that references to a bonnet assembly include references to the bonnet assembly for both a vehicle compartment of a motor vehicle and a luggage space of a motor vehicle.

Claims

CLAIMS 1. A bonnet assembly for a motor vehicle comprises an outer panel and a profile member extending along at least part of at least one edge of the outer panel, the profile member comprising first and second flanges at either end of the profile member between which is located at least one step portion, the first flange being connected to the at least one edge of the outer panel, the at least one step portion being of a section such that it provides for controlled collapse of the step portion.
2. A bonnet assembly according to claim 1, characterised in that the step portion comprises an upper generally vertical part, the upper generally vertical part being of varying height along a length thereof.
3. A bonnet assembly according to claim 1 or claim 2, characterised in that the first flange is retained within a lapped edge forming part of the at least one edge.
4. A bonnet assembly according to any previous claim, characterised in that the second flange runs substantially parallel to a region of the outer panel to which it is adjacent.
5. A bonnet assembly according to any preceding claim, characterised in that the profile member has two stepped portions.
6. A profile member for location at at least one edge of a motor vehicle bonnet assembly comprises first and second flanges at either end of the profile member between which is located at least one step portion, the at least one step portion being of a section such that it provides for controlled collapse of the step portion.
7. A profile member according to claim 6, characterised in that the step portion comprises an upper generally vertical part, the upper generally vertical part being of varying height along a length thereof.
8. A profile member according to claim 5 or claim 6, characterised in that the profile member has two stepped portions.
9. A bonnet assembly substantially as described herein with reference to and as illustrated in the accompanying drawing.
10. A profile member for location at at least one edge of a motor vehicle bonnet assembly substantially as described herein with reference to and as illustrated in the accompanying drawing.