GB2444247A

GB2444247A - A vehicle component for supporting a sunroof mechanism and deflecting an expanding airbag

Info

Publication number: GB2444247A
Application number: GB0623793A
Authority: GB
Inventors: Murray Johnson
Original assignee: Nissan Motor Manufacturing UK Ltd
Current assignee: Nissan Motor Manufacturing UK Ltd
Priority date: 2006-11-29
Filing date: 2006-11-29
Publication date: 2008-06-04
Anticipated expiration: 2026-11-29
Also published as: GB0623793D0; GB2444247B

Abstract

A vehicle structure or a component 10 is provided for attachment to a vehicle structure such as a cant rail 40 along the side of the vehicle. The structure or component comprises a sunroof/sunblind mechanism mounting platform 12 that defines a deployment control surface 28 for a curtain airbag. The deployment control surface may be a reaction surface which directs the expanding airbag in a generally downwards direction. Further deflection surfaces, such as ramps 34, 36, may also be provided for deflecting the airbag. The component may comprise a bracket attached to the vehicle, or it may be formed in the surface of an inner panel of the cant rail.

Description

VEHICLE STRUCTU1ES OR COMPONENTS DEFINING A DEPLOYMENT

CONTROL SURFACE FOR AN AIRBAG

This invention relates to vehicle airbag systems and in particular to a vehicle structure or component defining a deployment control surface for an airbag, especially a curtain airbag.

Increasingly stringent safety standards have resulted in the widespread adoption of curtain airbag systems in vehicles such as cars. Curtain airbag systems typically comprise an elongate airbag stowed behind the headlining or other interior trim panels to each side of a vehicle roof. The airbag is typically stowed under, within or inboard of longitudinal roof members (otherwise known as cant-rails') above the vehicle side windows.

The purpose of a curtain airbag is to improve protection against side impacts and roll-over impacts by inflating between the side windows of a vehicle and its occupants.

This helps to protect the occupants against impact with the vehicle interior and intruding vehicle structure during a collision. It also helps to keep the occupants contained within the vehicle.

In order to work, a curtain airbag must inflate outboard of the occupants and inboard of the side windows. This requires careful control of deployment during the rapid inflation of the airbag, to ensure that the inflated airbag reaches its intended location quickly and reliably. In doing so, the airbag must avoid damage from nearby vehicle components such as pieces of vehicle trim, seat belt mountings and sunroof mountings. Also, where possible, interior trim panels and other components not become detached and interact undesirably with the curtain airbag or the occupants during airbag deployment. Trim panels that conceal an airbag are usually designed to deflect aside as the airbag inflates but to remain anchored to the vehicle structure throughout.

Control of curtain airbag deployment may be effected to an extent by deployment control surfaces which are attached to or formed in the vehicle structure, typically along the cant-rails above the vehicle side windows. Deployment control surfaces typically take the form of reaction surfaces and/or deflection surfaces, also known as ramps. Reaction surfaces are inclined to impart a desired generally downward movement to the curtain airbag in reaction to the inflation of the airbag, whereas deflection surfaces are inclined to deflect the airbag during deployment, so that it is deployed clear of, and hence is prevented from hanging' on items of vehicle trim.

Thereafter the airbag may be restrained by tethers or other attachments to the vehicle structure. Curtain airbags are typically stowed below reaction surfaces, and above deflection surfaces.

It is desirable to minimise the number of operations and components required to manufacture a vehicle. However, the provision of airbag deployment control surfaces may require components to be attached to the vehicle or curtain airbag assembly. For example, airbag mounting brackets may be adapted to provide deployment control surfaces.

As another issue, many modem vehicles include a sunroof having a retractable sunblind that, when retracted, is stored in a region generally above and behind the heads of passengers travelling in the back seats of the vehicle. The sunblind may be of a roller-blind or lamella type. The sunroof may itself be retractable. There is therefore a need for a sunroof mechanism in this region for driving and storing the sunblind and/or sunroof. Such a mechanism, which will be referred to herein as sunroof mechanism for brevity, typically forms a cross member on a sunroof mechanism mounting bracket attached, via suitable bracketry, to a cant-rail. Stowed curtain airbags are usually located close to the sunroof mechanism, and it is important that the mechanism does not interfere with the deployment of the airbag and that the airbag fits around the mechanism and the supporting bracket.

It is against this background that the invention has been devised.

The invention resides in a vehicle structure or in a component for attachment to a vehicle structure, the structure or component comprising a mounting for a sunroof mechanism, wherein the mounting defmes a deployment control surface for a curtain airbag.

The invention employs a sunroof mechanism mounting to perform the additional role of defining a deployment control surface for a curtain airbag. In doing so, the invention minimises the number of operations and components necessary to make a vehicle. Additionally, the invention ensures that the sunroof mechanism mounting will not hinder correct deployment of the airbag or be caused to detach as the airbag inflates.

The deployment control surface may be a reaction surface for directing a curtain airbag in a generally downward direction, or a deflection surface for deflecting the curtain airbag during deployment. In a preferred embodiment of the invention, the deployment control surface is a reaction surface which is suitably below the mounting when the structure or component is oriented in use.

The mounting may be defmed by a projecting part of the component or structure, and the projecting part may comprise a platform for supporting a sunroof mechanism.

The reaction surface may be defmed at least partially by a surface of the platform.

The mounting may comprise an additional deployment control surface. For example, in addition to a reaction surface, the mounting may comprise a deflection surface for deflecting the curtain airbag, upon deployment, past various protruding components in the vehicle, such as seat belt mounts, or portions of vehicle trim. This prevents the airbag being damaged by such components or causing such components to detach and cause injury. Preferably such a deflection surface is a ramp. The ramp may extend in an inboard direction. Where the invention is embodied in a component for attaching to a vehicle structure, the ramp may be a lowermost portion of the component. When the structure or component is installed in a vehicle, the ramp is preferably located directly above the protruding component.

The mounting may comprise first and second additional deployment control surfaces in the form of ramps which are respectively located directly above first and second protruding components when the structure or component is installed in a vehicle. The first ramp extends by a first distance and is oriented to direct a curtain airbag clear of the first projecting component when the airbag is deployed. The second ramp extends by a second distance and is oriented to direct a curtain airbag clear of the second protruding component when the airbag is deployed. The first and second protruding components may, for example, be portions of vehicle trim which protrude to different extents. The first and second distances may be different to allow the airbag to be deployed clear of the two portions of differently projecting trim. Other embodiments of the invention may comprise any number of additional deployment control surfaces such as ramps so that a curtain airbag can be deployed clear of any number of differently projecting portions of trim.

Where the invention is embodied in a vehicle structure, the mounting and its reaction surface may be formed as a feature in the inner panel of a cant-rail. Conversely, where the invention is embodied in a component, that component may be a bracket further including means for attachment to a vehicle structure. The bracket may be formed by a metallic pressing, casting or extrusion or, alternatively, from a suitable polymeric material. The bracket may be a single moulding. Moreover, where the device is a component, it may be held in place by clips, adhesive, welding or other suitable securing means instead of being bolted to the vehicle body.

The inventive concept encompasses a cant-rail assembly having the structure or component of the invention as defmed above mounted thereto or integral therewith.

The inventive concept also encompasses a vehicle having the structure or component of the invention as defined above.

In order that the invention may be more readily understood, reference will now be made by way of example to the accompanying drawings in which: Figure 1 is a perspective view of a bracket according to the invention, comprising a mounting for a sunroof or sunblind, the mounting having a reaction surface for a curtain airbag; Figure 2 is an internal side view of a vehicle body structure with the bracket of Figure 1 and a curtain airbag attached; Figure 3 is a perspective view of the bracket shown in Figures 1 and 2, showing a curtain airbag located below the mounting and inboard of the reaction surface of the bracket; Figure 4 is a first schematic section through a cant-rail, bracket and curtain airbag, taken along the line A-A in Figure 3; and Figure 5 is a second schematic section through a cant-rail, bracket and curtain airbag, taken along the line B-B in Figure 3.

A sunroof mechanism mounting bracket 10 according to the invention is shown in Figure 1. The bracket 10 comprises a base plate 11 with a substantially central platform 12 projecting from an upper edge 13 of the base plate 11. In this example, the base plate 11 is substantially flat, however in general the base plate 11 is shaped to interface with the corresponding supporting structure to which it is mounted. First and second arms 14,16 extend upwards from the base plate 11 respectively to each side of the platform 12. Threaded fasteners 18 are shown in Figure 1 which extend through an end portion 20 of each arm 14,16 and are provided for securing the bracket to a vehicle body structure (not shown). The bracket 10 is also secured to the vehicle body structure by further threaded fasteners (not shown) which pass through apertures (not shown) in the base plate 11.

When the bracket 10 is secured to a vehicle body structure, the platform 12 is substantially horizontal and projects inboard, and is used to support a sunroof mechanism (not shown). The platform 12 includes swages 24 to increase the rigidity of the platform 12.

Referring to Figures 1 and 2, the bracket 10 includes a reaction surface 28 for directing the motion of a curtain airbag 26 when the airbag is deployed, as described in more detail later with reference to Figure 4 and 5. The reaction surface 28 is defined at least partially by an overhanging surface 30 of the platform 12, which can be seen more clearly in Figure 5. When the bracket 10 is attached to the body structure of a vehicle, and a sunroof mechanism is supported by the platform 12, the reaction surface 28 is below the sunroof mechanism.

Depending from a lower portion 32 of the base plate 11 is a first ramp 34 which extends generally below, and longitudinally beyond the first arm 14. Additionally a second ramp 36 depends from the base plate 11, the second ramp 36 generally extending below the platform 12 and the second arm 16. Each ramp 34, 36 extends in an inboard and downward direction when the bracket 10 is attached to a vehicle body structure. This direction is illustrated by Arrow D in Figures 4 and 5. The respective functions of the first and second ramps 34, 36 are described in more detail later with reference to Figures 4 and 5 respectively.

Figure 2 shows the sunroof mechanism mounting bracket 10 attached to a vehicle body structure 38. The part of the vehicle body structure 38 shown in Figure 2 comprises a cant-rail 40 with an A-pillar 42, a B-pillar 44 and a C-pillar 46 supporting the cant-rail 40. The A and B pillars 42, 44 defme a front side-door aperture 48, and the B and C pillars 44, 46 defme a rear side-door aperture 50. A rear quarter window region 52 is disposed behind the C-pillar 46. The bracket 10 is attached to the cant-rail 40 in a region generally above the C-pillar 46 such that a sunroof mechanism mounted on the bracket 10 will allow a sunroof andlor a sunblind to retract above and behind the heads of rear seat occupants Two similar brackets 10 (one a mirror image of the other) would typically be installed opposite one another on respective cant-rails of the vehicle, one to each side of a vehicle roof to support a sunroof mechanism. The platforms 12 of each bracket 10 cooperate to support the sunroof mechanism as a cross member.

A curtain airbag 26, in its stowed state, is attached to an inner panel 56 of the cant-rail 40. The curtain airbag 26 extends along the cant-rail 40 above the front side-door aperture, rear side-door aperture and rear quarter window regions 48, 50, 52. The curtain airbag 26 is located below the platform 12 as best seen in Figure 3. The curtain airbag 26 is therefore also located below reaction surface 28 as shown in Figure 1.

A piece of interior trim 58 surrounds the rear quarter window region 52 as shown in Figure 3. This piece of interior trim 58 has a first, upright portion 60 forward of the rear quarter window region 52 and extending along the C-pillar 46, and a second, generally horizontal portion 62 located along the top of said region 52. The bracket is attached to the cant-rail 40 above the rear quarter window region 52, such that the first ramp 34 is located directly above the first portion of trim 60, and the second ramp 36 is located directly above the second portion of trim 62. The second portion 62 projects inboard to a greater extend than the first portion 60. The function of the ramps 34, 36 will now be described in more detail with reference to Figures 4 and 5.

Figure 4 is a schematic section through the cant-rail 40, bracket 10 and curtain airbag 26, taken along the line A-A in Figure 3. The section in Figure 4 is taken through the first arm 14 and the first ramp 34 of the bracket 10, and features an upper edge 64 of the first portion of interior trim 60 shown in Figure 3. The first ramp 34 is oriented such that an extension of the first ramp 34 would clear the first portion of Irim 60.

Figure 5 is a schematic section through the cant-rail 40, bracket 10 and curtain airbag 26, taken along the line B-B in Figure 3. The section in Figure 5 is taken through the platform 12 and second ramp 36, and features an upper edge 66 of the second portion of interior trim 62 shown in Figure 3. The second ramp 36 is oriented such that an extension of the second ramp 36 would clear the second portion of trim 62.

In use, when the curtain airbag 26 is deployed, the reaction surface 28 of the bracket exerts a reaction force on the curtain airbag 26 which causes it to be deployed in a generally downward direction. The ramps 34, 36 ensure that the airbag 26 is deflected clear of the various items of vehicle trim 60, 62. Additionally, because the curtain airbag 26 is stowed below the sunroof and sunroof mounting, and the reaction surface 28 ensures a downward deployment of the curtain airbag 26, the sunroof and sunroof mounting will not interfere with deployment of the curtain airbag 26.

Although the embodiment described is a separate component for attaching to the vehicle body structure, the invention can also be embodied in a part of the vehicle body structure. For example, a part of the cant-rail inner panel can be shaped to provide both the mounting for a sunroof, and one or more deployment control surfaces for a curtain airbag, Many other variations are also possible within the ambit of the invention. Reference should therefore be made to the appended claims rather than the foregoing specific description as indicating the scope of the invention.

Claims

Claims I. A vehicle structure or a component for attachment to a

vehicle structure, the structure or component comprising a mounting for a sunroof mechanism, wherein the mounting defines a deployment control surface for a curtain airbag.
2. The vehicle structure or component of Claim 1, wherein the deployment control surface is a reaction surface arranged to direct the curtain airbag in a generally downward direction on deployment.
3. The vehicle structure or component of Claim 2, wherein the mounting is defined by a projecting part of the component or structure.
4. The vehicle structure or component of Claim 3, wherein the projecting part provides a means for supporting a sunroof mechanism.
5. The vehicle structure or component of Claim 3 or Claim 4, wherein the reaction surface is defined at least partially by a surface of the projecting part.
6. The vehicle structure or component of any of Claims 2 to 5, wherein the reaction surface is above the curtain airbag, in use.
7. The vehicle structure or component of any preceding claim further comprising a deflection surface arranged to guide the curtain airbag during deployment, said deflection surface serving as an additional deployment control surface.
8. The vehicle structure or component of Claim 7, wherein the deflection surface is defined by a first ramp which extends inboard from the structure or component when the structure or component is oriented in use.
9. The vehicle structure or component of Claim 8, further comprising a second ramp which extends inboard from the structure or component when the structure or component is oriented in use, said second ramp serving as an additional deflection surface, wherein the first and second ramps extend from the structure or component to different extents.
10. The vehicle structure or component of Claim 1, wherein the deployment control surface is a deflection surface arranged to deflect the curtain airbag during deployment.
11. The vehicle structure of any preceding claim, wherein the mounting and the or each deployment control surface is formed in the surface of the inner panel of a cant-rail.
12. The vehicle component of any of Claims 1 to 10, wherein the component is a bracket and the bracket includes means for attachment to a vehicle structure.
13. A cant-rail assembly comprising the bracket of Claim 12 mounted thereto or integral thereth.
14. A vehicle having the structure or component of any preceding claim.
15. The vehicle of Claim 14, further comprising a stowed curtain airbag disposed adjacent to the or each deployment control surface.
16. A vehicle structure or a component for attachment to a vehicle structure, substantially as herein described, with reference to or as shown in the accompanying drawings.