GB2366773A

GB2366773A - Vehicle steering column ride down apparatus

Info

Publication number: GB2366773A
Application number: GB0121384A
Authority: GB
Inventors: Michael Thomas Hancock; Seiichi Moriyama; Yuichiro Fukunaga; Yasuhisa Yamada
Original assignee: NSK Steering Systems Europe Ltd
Current assignee: NSK Steering Systems Europe Ltd
Priority date: 2000-09-19
Filing date: 2001-09-04
Publication date: 2002-03-20
Anticipated expiration: 2021-09-04
Also published as: GB2366773B; GB0121384D0; GB2366772A; GB0022963D0

Abstract

Vehicle steering column ride down apparatus to guide the direction of steering column collapse in the event of vehicle crash includes a first part (1) for fixedly mounting to a support such as a cross car beam and a second part (2) for coupling to a steering column assembly (3). At least one of the parts is tracked to act as a guidance and the other part has first means (8 or 9) to run in the or each track and there being second means (8 or 9) to tighten the two parts, one upon the other, to provide a predetermined frictional resistance at least to initial relative break-away movement of the two parts (1,2) in the event of vehicle crash. The or each track may be constituted by at least one slot (7). Coated plates (10A, 10B) (fig 5) can be clamped between flanges (5, 6) of the parts (1, 2), which are each in the form of brackets to provide further initial frictional resistance to the initial relative break-away movement of the two parts (1, 2).

Description

VEHICLE STEERING COLUMN RIDE DOWN APPARATUS This invention relates to a

vehicle steering column ride down apparatus that aims to simplify known forms of 5 such apparatus. Such ride down apparatus is incorporated in vehicle steering column assemblies in order to guide the direction of steering column collapse in the event of vehicle crash.

10 According to the present invention, there is provided a vehicle steering column ride down apparatus, comprising a first part for fixedly mounting to a support in the vehicle and a second part for coupling to a steering column assembly; characterised in that at least is one of the parts is tracked to act as a guidance and the other part has first means to run in the or each track and there being second means to tighten the two parts to provide a predetermined resistance at least to initial relative movement of the two parts in the event of 20 vehicle crash.

The first part may be a fixed mounting bracket and may be provided with two parallel flanges, each with a longitudinal slot forming tracks in which said first 25 means can run.

The second part may form a steering column support bracket and may be sized to fit within the two parallel flanges of the first part.

The second part may also be provided with two parallel flanges, each with longitudinal slots therein to form tracks in which the first means can run.

The first means can be formed by at least one screw fitting between the two parts. There may be at least one screw fitted in a screw aperture in the first part and tracking in one of the slots of the second part and there 5 may be at least one screw in a screw aperture of the second part tracking in one of the slots of the first part.

The first means and the second means can be one and 10 the same means.

Nuts may be tightened on the or each screw to provide the required torque for said predetermined resistance to relative movement of the two parts in the is event of vehicle crash.

When the two parts are fitted one within the other, slots of adjacent flanges align with one another.

20 The invention also extends to a vehicle steering column assembly incorporating a steering column ride down apparatus essentially as defined above.

For a better understanding of the invention and to 25 show how the same may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which:

Figure 1 is a diagrammatic exploded perspective view 30 of part of a vehicle steering column ride down apparatus; Figure 2 is a diagrammatic side view of the apparatus shown in Figure 1, shown in an installed condition on a vehicle steering column assembly; Figure 3 is a diagrammatic side view of the apparatus and assembly shown in Figure 2 showing the condition of the apparatus after a vehicle crash; 5 Figure 4 is a view similar to Figure 2 but illustrating a form of mounting where movement of the steering column assembly during vehicle crash takes place axially of the main steering column i.e. at an acute angle to the column axis, rather than horizontally, as is 10 the case with Figure 2, and Figure 5 is a view similar to Figure 1 and shows a modification.

15 The Figures show a first part in the form of a fixed mounting bracket 1 for fixedly mounting to a support bracket such as a car cross beam (not shown) and a second part in the form of a steering column bracket 2 for coupling to a steering column assembly 3. A steering 20 wheel 4 is also diagrammatically illustrated in Figures 2 and 4.

The mounting bracket 1 has two depending parallel flanges 5 and the steering column bracket 2 is of basic 25 channel section with two resulting parallel side flanges 6, that are designed to fit within the two flanges 5 of the bracket 1 (see arrow A in Figure 1).

Both the bracket 1 and the bracket 2 are provided 30 with closed guide slots 7 in their side flanges 5, 6 respectively. Bolt or screw connections 8, 9 are provided that are screwed into screw apertures in the brackets 1, 2 respectively and are fitted so that they pass into the slots 7 of the adjacent brackets, fitting in the locations 8A, 9A respectively as shown in Figure 1. Each screw is tightened to a predetermined torque to hold the brackets relatively fixed during normal vehicle us e.

5 The mounting bracket 1, being fixed to a support in the vehicle such as a vehicle cross car beam, will allow the steering column bracket 2 to break away in the event of vehicle crash from the mounting points formed by the screws 8 and 9 which have been tightened to their preset 10 torque.

It will be noted that in the event of crash, the pairs of screws 8,9, once they break away from their normally fixed positions by initially each overcoming its 15 predetermined torque, run down their respective slots 7, the screws 8 being held captive in their mountings in the inner steering column bracket 2 and running in the two slots 7 in the outer, fixed bracket 1, whilst the screws 9 are held captive in their mountings in the outer, fixed 20 bracket 1 running in the two slots 7 in the inner bracket 2, at most until both sets of screws reach the end of their respective slots (assuming that both sets of slots are of equal length).

25 The crash path of the collapsing steering column will therefore be guided by the slots 7 in a controlled horizontal path as indicated by the arrows B in Figure 2 or parallel to the column axis as shown by the arrow C in Figure 4. Once the original torque has been overcome, 30 there is comparatively low friction resistance between the parts 1 and 2.

The modification shown in Figure S is a secondary device to provide further initial increased friction or resistance to break-away. This device includes two coated plates 10A fitted to the end of the mounting 5 bracket 1 that lies upstream of the direction of break away movement of the steering column bracket 2. The coated plates 10A are fitted one to each side flange 5 of the mounting bracket 1.

10 Two further coated plates 10B are fitted to the end of the steering column bracket 2 that lies downstream of the direction of break-away movement of the steering column bracket 2. The coated plates 10B are fitted one to each side flange 6 of the steering column bracket 2.

Each coated plate 10A, 10B is given the form of a narrow U-shaped element of substantially rectangular configuration when viewed in side elevation. Two wings 11 of the element are spaced-apart sufficiently to be 20 fitted about the thickness of its side flange 5, 6.

Each wing 11 of each coated plate 10A, 10B is given an open groove 12 to accommodate one of the screws or screw bolts 9 passing through the flanges 5, 6.

To provide the increased friction or resistance initially upon break-away in the event of vehicle crash, the coated plates 10A, 10B are clamped between the brackets 5 and 6. On break-away, the brackets 5, 6, 30 which are non-coated for these purposes, move freely relatively to one another once the coated plates 10A, 10B have been disengaged. Accordingly, friction is reduced during full ride-down of the steering column in the event of vehicle crash.

It will be appreciated that the arrangement and number of coated plates 10A, 10B could be variedand altered. For example, the plates 10A could be fitted on the side flanges 6 and the plates IOB could be fitted on 5 the side flanges 5 or all could be fitted on one or the other.

It will be appreciated that the present construction provides a low cost steering column crash path control 10 device and a low friction mechanism with horizontal path control.

In use, there will also be resistance to steering column deflection in a vertical plane in the event of 15 vehicle crash, whilst the screw connections will provide a variable break-away force.

Furthermore, the low friction referred to comes as a result of vertical bending forces during crash 20 conditions.

The device is also independent of other vehicle installations and can be supplied as a compact package utilising minimal space in the vehicle.

Claims

1 A vehicle steering column ride down apparatus, comprising a first part for fixedly mounting to a support 5 in the vehicle and a second part for coupling to a steering column assembly; wherein at least one of the parts is tracked to act as a guidance and the other part has f irst means to run in the or each track and there being second means to tighten the two parts to provide a 10 predetermined resistance at least to initial relative movement of the two parts in the event of vehicle crash.

2. An apparatus according to claim 1, wherein a secondary device is provided to provide further initial is increased resistance to initial relative movement of the two parts in the event of vehicle crash.

3. An apparatus according to claim 1 or 2, wherein said first part is a fixed mounting bracket provided with 20 two parallel flanges, each with a longitudinal slot forming tracks in which said first means can run.

4. An apparatus according to claim 1, 2 or 3, wherein said second part forms a steering column support 25 bracket.

5. An apparatus according to claim 3 or claims 3 and 4, wherein said second part is sized to fit within the two parallel flanges of said first part.

6. An apparatus according to any one of the preceding claims, wherein said second part is provided with two parallel flanges, each with longitudinal slots therein to form tracks in which said first means can run.

7. An apparatus according to any one of the preceding claims, wherein said first means is formed by at least one screw or screw bolt fitting between the two 5 parts.

8. An apparatus according to claims 3, 6 and 7, wherein at least one said screw or screw bolt is fitted in a screw aperture in said first part and tracks in one 10 of the slots of said second part and wherein there is at least one said screw or screw bolt in a screw aperture of said second part tracking in one of the slots of said first part.

15 9. An apparatus according to claim 7 or 8, wherein nuts are tightened on the or each screw or screw bolt, to provide the required torque to said predetermined resistance to relative movement of the two parts in the event of vehicle crash.

10. An apparatus according to any one of the preceding claims, wherein said first and second means are one and the same means.

25 11. An apparatus according to claims 5 and 6 or any one of claims 7 to 10 as appendant to claims 5 and 6, wherein, when said two parts are fitted one in the other, the slots of adjacent flanges align with one another.

30 12. An apparatus according to claims 2 and 3 or any one of claims 4 to 11 as appendant to claims 2 and 3, wherein said secondary device includes two coated plates fitted to one end of the fixed mounting bracket.

13. An apparatus according to claim 12, wherein said two coated plates are fitted one to each of said parallel flanges.

5 14. An apparatus according to claims 2 and 4 or any one of claims 5 to 13 as appendant to claims 2 and 4, wherein said secondary device includes two coated plates fitted to one end of the steering column bracket.

10 15. An apparatus according to claim 14 as appendant to claim 6, wherein the two coated plates that are fitted to the end of the steering column bracket are fitted one to each of said parallel flanges of the steering column bracket.

16. An apparatus according to claim 12, 13, 14 or 15, wherein each said coated plate is given the form of a U-shaped element of substantially rectangular configuration when viewed in side elevation.

17. An apparatus according to claim 16 as appendant to claim 13 or 15, wherein each said element has two wings that are spaced-apart sufficiently to be fitted about the thickness of the respective side flange.

18. An apparatus according to claim 17 as appendant to claim 7, wherein each said wing of each said coated plate is given an open groove to accommodate said at least one screw or screw bolt fitting between the two 30 parts.

19. An apparatus according to any one of claims 12 to 18, wherein each said coated plate is clamped between its associated bracket to provide the increased resistance at least to initial relative movement of the two parts in the event of vehicle crash.

20. A vehicle steering column ride down apparatus, 5 substantially as hereinbefore described, with reference to Figures 1 to 4, with or without the modification of Figure 5, of the accompanying drawings.

21. A vehicle steering column assembly 10 incorporating a steering column ride down apparatus according to any one of the preceding claims.