GB2324508A

GB2324508A - Motor vehicle dashboard structure

Info

Publication number: GB2324508A
Application number: GB9708106A
Authority: GB
Inventors: Michael Mellor
Original assignee: MG Rover Group Ltd
Current assignee: MG Rover Group Ltd
Priority date: 1997-04-22
Filing date: 1997-04-22
Publication date: 1998-10-28
Also published as: GB9708106D0

Abstract

A vehicle structure comprises a dashboard 14 attached to a bulkhead 13 with at least two vertically arranged crushable members 15 between the dashboard and the bulkhead. The crushable members may connect the dashboard to the bulkhead and may be in the form of thin walled tubes (19 figure 5) filled with impact absorbing material such as closed cell plastic foam (20 figure 5). Four crushable members may be provided spaced apart along the length of the dashboard (figure 3) behind a deformable plastic panel of the dashboard in positions generally corresponding to the normal locations of vehicle occupants legs. The crushable members may serve to protect the legs of an occupant P of the vehicle and act as a knee bolster (figure 2).

Description

A motor vehicle and a Knee bolster arranaement therefor This invention relates to motor vehicles and in particular to a knee bolster to cushion the impact of an occupants legs during a collision of the motor vehicle with another vehicle or structure.

It is known from US-A-4,065,157 to provide a knee bolster for a motor vehicle having a crushable structure extending across the vehicle that can be crushed or deformed by contact with the knees or leg parts of the occupants during a severe collision.

It is a problem with such a knee bolster that it occupies a considerable amount of space behind the dashboard.

It is an object of this invention to provide a more compact knee bolster for a motor vehicle.

According to the invention there is provided a motor vehicle having a body structure defining a passenger compartment and an engine compartment separated from the passenger compartment by a bulkhead and a dashboard assembly attached to said bulkhead by means of two or more crushable members wherein each of said crushable members extends in an upward direction.

Preferably the dashboard is connected to the bulkhead by means of said crushable members.

Each of said crushable members may be a thin walled tube.

Each of the thin walled tubes may be filled an impact absorbing material.

The impact absorbing material may be a closed cell plastic foam.

There may be four crushable members spaced apart along the length of the dashboard assembly.

Each of the crushable members may be positioned behind a deformable panel forming part of the dashboard assembly.

The deformable panel may be made from a plastics material.

The invention will now be described by way of example with reference to the accompanying drawing of which: Fig. 1 is a cross-section through part of a motor vehicle according to the invention; Fig.2 is a view similar to that shown in Fig. 1 but showing the motor vehicle in a collision configuration; Fig. 3 is a view in the direction of the arrow A of Fig. 1; Fig.4'is a side view of a knee bolster forming part of the motor vehicle; and Fig.5 is a cross-section on the line V-V on Fig.4.

With reference to the figures there is shown a motor vehicle 10 having a body structure defining a passenger compartment 11 separated from an engine compartment 18 by a structural bulkhead 13. A seat 12 is fixed to a floor member of the body structure to provide a support for a passenger P to be transported by the motor vehicle.

A dashboard assembly 14 extends across the passenger compartment at the front end thereof and includes an instrument panel 17. The dashboard assembly is made primarily from a plastics material and provides not only a decorative finish for the interior of the vehicle but also supports various ancillary components such as the instrument panel 17 and the controls for various functions on the vehicle (not shown).

Four spaced apart crushable members in the form of knee bolsters 15 are interposed between the dashboard 14 and the bulkhead and are used to attach the dashboard 14 to the bulkhead. Knee bolsters 15 are spaced apart along the length of the dashboard assembly 14 such that they are generally located two on either side of the motor vehicle adjacent to the position of the passenger's legs during normal use. The portion of the dashboard assembly which overlies the knee bolsters 15 is made from a plastics material and is designed to deform if it is impacted upon by the legs of a passenger P of the motor vehicle.

As is best seen with reference to Figs.4 and 5 each of the knee bolsters 15 is formed as a thin walled tube 19 which is filled with a closed cell plastic foam 20 designed to absorb energy as the knee bolster 15 is crushed.

This structure has the advantage that when crushed the thin walled tube 19 prevents any rebound energy from being transferred back to the occupants knees, in effect once crushed the tube 19 stays crushed.

A pair of threaded fixings 21 are fastened to one side of the knee bolster 15 to provide a means of connecting the knee bolster 15 to the dashboard assembly 14 and a pair of threaded inserts 22 are affixed to the opposite wall of the knee bolster 15 to provide a means of attaching the knee bolster 15 to the bulkhead 13 of the motor vehicle.

In normal use the knee bolsters 15 are arranged to extend upwardly between the dashboard assembly 14 and the bulkhead 13 and are used to attach the dashboard assembly 14 to the bulkhead 13.

In the event of a serious collision as shown in Fig.2 the legs of a passenger carried by the motor vehicle will come into contact with the panel 16. The panel 16 will then be urged forwardly towards the bulkhead 13 against the resistance offered by the knee bolsters 15. If the collision is sufficiently severe the knee bolsters 15 will be crushed by the forward movement of the panel 16 thereby absorbing energy.

It will be appreciated that the positioning of the knee bolsters 15 does not have to coincide with the impact position of the passenger's legs upon the panel 16 and in fact it is normally the case that the position of impact of the passenger's knees against the deformable panel 16 will be slightly offset from the positions of attachment of the dashboard 14 to the knee bolsters 15.

Although the knee bolsters 15 have been described herein as extending upwardly by this it is meant any arrangement in which the knee bolsters 15 extend in a general vertical direction from a lower position on the dashboard assembly 14 to a higher position on the dashboard assembly 14.

It will be appreciated that the knee bolster tubes can be made from any suitable material which when crushed is plastically deformed.

Claims

1. A motor vehicle having a body structure defining a passenger compartment and an engine compartment separated from the passenger compartment by a bulkhead, a dashboard assembly attached to said bulkhead and two or more crushable members interposed between the dashboard and the bulkhead wherein each of said crushable members extends in a generally upwardly direction.

2. A motor vehicle as claimed in Claim 1 in which the dashboard is connected to the bulkhead by means of said crushable members.

3. A motor vehicle as claimed in Claim 1 or in Claim 2 in which each of said crushable members is a thin walled tube.

4. A motor vehicle as claimed in Claim 3 in which the thin walled tube is filled with an impact absorbing material.

5. A motor vehicle as claimed in Claim 4 in which the impact absorbing material is a closed cell plastic foam.

6. A motor vehicle as claimed in any of Claims 1 to 5 in which there are four crushable members spaced apart along the length of the dashboard assembly.

7. A motor vehicle as claimed in Claim 6 in which each of the crushable members is positioned behind a panel forming part of the dashboard assembly.

8. A motor vehicle as claimed in Claim 7 in which the panel is made from a plastics material.

9. A motor vehicle substantially as described herein with reference to the accompanying drawing.