GB2350333A

GB2350333A - Collapsible steering column incorporating a fluid-controlled shock absorber

Info

Publication number: GB2350333A
Application number: GB0012610A
Authority: GB
Inventors: Laurence George Herbert Barton; James Peter Bentley; Yasuhisa Yamada; Burt Weiner
Original assignee: Nastech Europe Ltd
Current assignee: Nastech Europe Ltd
Priority date: 1999-05-26
Filing date: 2000-05-25
Publication date: 2000-11-29
Also published as: GB0012610D0

Abstract

A collapsible steering column assembly for a vehicle incorporates an adjustable fluid-controlled shock absorber 3 which creates a greater or lesser resistance to relative movement between the shock absorber and the column 2 by varying fluid flow, during collapse of the column in the event of a vehicle crash, in response to an electric signal supplied by sensors sensing various sensed conditions of a driver in the vehicle. The shock absorber may be telescopic and controlled by means of a solenoid. The shock absorber may form part of the steering column and may be located between a steering wheel and a yoke 1 of the assembly. The shock absorber may be formed from a static external cylinder 4 and an internal member 15 that rotates with the wheel. Means may be provided to update the sensed data so that the fluid flow may be continually adjusted.

Description

2350333 COLLAPSIBLE STEERING COLUMN ASSEMBLY FOR A VEHICLE This invention

relates to a collapsible steering column assembly for a vehicle.

Developments are now progressing towards "smart" steering columns, and this invention has for its purpose to provide a steering column which can be collapsed in the event of a vehicle crash in a way that takes into account various physical characteristics of the driver, such as weight, posture, position and dimensions.

According to the present invention, there is provided a collapsible steering column assembly for a vehicle, the assembly incorporating a fluid-controlled shock absorber, there being means to adjust fluid flow in is the shock absorber, thereby to create a greater or lesser resistance to relative movement between the shock absorber and the steering column during collapse of the steering column in the event of vehicle crash; characterised by means to supply an electric signal to the shock absorber to control fluid flow, the electric signal being itself supplied by sensors sensing various sensed conditions of a driver of the vehicle.

The shock absorber can comprise a pneumatically or hydraulically actuated piston and cylinder arrangement.

The means to adjust fluid flow within the shock absorber can thereby create a greater or lesser resistance to relative movement between the piston and cylinder arrangement and another part of the steering column assembly during the collapse.

The steering column can be rake and/or reach adjustable and the fluid means can be arranged normally to allow such adjustment. After such adjustment, a system can be activated, preferably by electronic means, to set the desired flow of fluid within the piston and cylinder arrangement, dependent upon predetermined sensed conditions.

The shock absorber can be a telescopic shock absorber and can be incorporated as part of the steering column, being located between a steering wheel and a yoke of the steering column assembly.

An outer cylinder of the shock absorber can be fixed relatively to an internal member, forming part of the steering column that rotates with rotation of the steering wheel.

is The invention also extends to a vehicle incorporating such a steering column assembly.

For a better understanding of the invention and to show how the same may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which:

Fig. 1 is a diagrammatic exploded perspective view of a collapsible steering column assembly incorporating a telescopic shock absorber, and Fig. 2 is a diagrammatic view of another embodiment of collapsible steering column assembly.

Fig. 1 shows a steering column assembly incorporating a lower yoke 1, an upper steering column tube or shaft 2, to which a steering wheel (not shown) is to be attached, and an intermediate, telescopic absorber 3.

The shock absorber 3 includes an external cylinder 4 which is held static, i.e. non-revolving, by being provided with keys 5 fitting in keyways 6 of a U-shaped bracket 7. The bracket 7 itself is mounted near one end by means of opposed pins 8 within curved slots 9 of an outer bracket 10. At the other end of the bracket 7, a pivot block 11 is fitted inside the bracket, the pivot block 11 being provided with pivot pins 12 fitting in pivot apertures 13 in the outer bracket 10. The pivot block 11 has a central aperture housing a bearing 14 rotatably to receive and support a rotating inner member of the shock absorber 3.

It will be appreciated that reach adjustment of the steering column can be achieved by sliding of the keys 5 in the keyways 6, whilst rake adjustment of the steering column can be achieved by up and down movement of the bracket 7 pivoting about the pins 12 with the pins 8 riding in the slots 9 of the bracket 10. As illustrated, the rake adjustment can also be controlled by fluid operated piston and cylinder arrangements 16, of which only one is illustrated.

The shock absorber 3 can be solenoid controlled or controlled electrically in another fashion in order to be able to adjust the energy absorption qualities of the shock absorber in the event of steering column collapse during a vehicle crash.

The shock absorber 3 is constructed such that flow of fluid, preferably hydraulic fluid, within it can be increased or restricted, thereby creating a greater or lesser resistance to movement.

This is achieved electrically by means of an electric signal supplied by sensors sensing various sensed conditions. For example, upon entry to the 4 vehicle, the occupant assumes a driving position and the various sensors can calculate weight, posture, position, etc. and thereby predetermine the settings required for energy absorption with a view to protecting the driver from serious injury as a result of steering column collapse in the event of vehicle crash.

The fluid means of the shock absorber 3 allows for normal rake and/or reach adjustment of the steering column 2. Once the driver has adjusted the steering column in its rake and/or reach modes, or in any case when the column is in its set adjusted position, a means (not shown) activates the system to set the desired flow of fluid within the shock absorber 3 so as to be dependent on the various sensed conditions.

When the system is active, the data can be updated every few seconds, e.g. by movement of the driver, which will result in a different posture, position, etc. so that the updated data is taken into account on an almost continual basis.

Figure 2 shows another embodiment, with a steering wheel 17 mounted on the steering column 2 forming part of a steering column assembly which is restrained to another part of the vehicle at mounting points 18. The steering column 2 is slidable in the form illustrated in a reach dimension, illustrated by the arrows A, being slidable within a mounting bracket 19.

In the event of vehicle crash, the steering wheel 17 with its column 2 and a column component 20 are required to collapse under controlled conditions. In the form illustrated, a hydraulic cylinder 21 of a piston and cylinder arrangement is rigidly mounted to the steering column bracket 19 and is linked via a push rod 22 attached by the piston to the column component 20. The piston and cylinder arrangement can include a spool valve.

The cylinder 21 is constructed such that flow of hydraulic fluid within it from one side of the piston to the other can be increased or restricted, thereby creating a greater or lesser resistance to movement of the push rod 22.

As with the Figure 1 embodiment, this is achieved electrically by means of an electronic signal supplied via sensors sensing various sensed conditions as described.

is Again, when the system is active, the data can be updated every few seconds, e.g. by movement of the driver, as described.

Claims

A collapsible steering column assembly for a vehicle,.the assembly incorporating a fluid-controlled shock absorber, there being means to adjust fluid flow in the shock absorber, thereby to create a greater or lesser resistance to relative movement between the shock absorber and the steering column during collapse of the steering column in the event of vehicle crash; characterised by means to supply an electric signal to the shock absorber to control fluid flow, the electric signal being itself supplied by sensors sensing various sensed conditions of a driver of the vehicle.
2. An assembly according to claim 1, wherein the shock absorber is a telescopic shock absorber.
3. An assembly according to claim 1 or 2, and comprising a solenoid to control the shock absorber, the solenoid being controlled by said means to supply an electric signal to the shock absorber.
4. An assembly according to any one of the preceding claims, wherein the shock absorber is incorporated as part of the steering column, being located between a steering wheel and a yoke of the steering column assembly.
5. An assembly according to any one of the preceding claims, wherein an external cylinder of the shock absorber is fixed relatively to an internal member that forms part of the steering column that rotates with rotation of the steering wheel.
6. An assembly according to claim 5, wherein said external cylinder is held in its static, non-revolving position by keys and key ways to allow for reach adjustment of the steering column. 5
7. An assembly according to any one of the preceding claims, wherein the steering column is rake and/or reach adjustable and wherein the fluid means is arranged normally to allow for such adjustment.
8. An assembly according to claim 7, wherein means is provided to activate a system, after said adjustment, to set the desired flow of fluid within the shock absorber, dependent upon predetermined sensed conditions.
9. An assembly according to any one of the preceding claims, wherein means is provided to update data in order to adjust fluid flow on a substantially continual basis.
10. A collapsible steering column assembly for a vehicle, substantially as hereinbefore described with reference to Figure 1 or Figure 2 of the accompanying drawings.
11. A vehicle incorporating a collapsible steering column assembly, according to any one of'the preceding claims.