STEERING COLUMN FOR A MOTOR VEHICLE

Abstract

A steering column may include a casing unit that can be connected to a body of a motor vehicle. A steering spindle may be rotatably mounted in the casing unit about a longitudinal axis. The casing unit may have an inner casing that is received in an outer casing so as to be telescopically adjustable in a direction of the longitudinal axis. A clamping device may be switchable between a fixing position in which it fixes the inner casing relative to the outer casing and a release position in which it allows telescopic adjustment of the inner casing relative to the outer casing. An energy absorption device may include a deformation element arranged between the inner casing and the outer casing. The casing unit may comprise a cable mounting that includes a fastening element for holding a cable and that is at least partly formed as a deformation element.

Claims

1.-9. (canceled)

10. A steering column for a motor vehicle comprising: a casing unit that is directly or indirectly connectable to a body of the motor vehicle, wherein a steering spindle is mounted in the casing unit so as to be rotatable about a longitudinal axis, the casing unit including an inner casing that is received in an outer casing so as to be telescopically adjustable in a direction of the longitudinal axis, and a cable mounting that has a fastening element for holding a cable, the cable mounting being at least partially formed as a deformation element; a clamping device configured to be switched between a fixing position where the clamping device fixes the inner casing relative to the outer casing and a release position where the clamping device allows telescopic adjustment of the inner casing relative to the outer casing; and an energy absorption device that includes a deformation element disposed between the inner casing and the outer casing.

11. The steering column of claim 10 wherein the cable mounting is attached to at least one of the inner casing or the outer casing.

12. The steering column of claim 10 wherein the cable mounting cooperates with at least one of the deformation elements, which upon relative movement of the inner casing and the outer casing is moved relative to the cable mounting and continuously deforms the cable mounting plastically in the direction of the longitudinal axis.

13. The steering column of claim 10 wherein the clamping device includes a clamping bolt that is rotatable about a clamping axis that is transverse to the longitudinal axis and that is connected to a clamping mechanism, wherein in the fixing position the clamping bolt cooperates with the cable mounting to deform the cable mounting plastically during relative movement of the inner casing and the outer casing.

14. The steering column of claim 13 wherein the clamping bolt passes through a longitudinal slot formed in the cable mounting and includes a deformation portion.

15. The steering column of claim 10 wherein the casing unit is mounted on a carrier unit that is connectable to the body of the motor vehicle.

16. The steering column of claim 15 wherein the carrier unit comprises at least one of a bracket or a pivot bearing.

17. The steering column of claim 15 wherein the clamping device is disposed on the carrier unit, which in the fixing position establishes the casing unit relative to the carrier unit and which in the release position allows adjustment of the casing unit relative to the carrier unit, at least in a height direction and/or in the direction of the longitudinal axis.

18. The steering column of claim 15 wherein the carrier unit comprises a secondary energy absorption device configured to absorb kinetic energy in a crash upon movement of the carrier unit relative to the body of the motor vehicle.

Description

DESCRIPTION OF THE DRAWINGS

[0029] Advantageous embodiments of the invention are explained in more detail below with reference to the drawings. The drawings show:

[0030] FIG. 1 a diagrammatic, perspective view of a steering column according to the invention,

[0031] FIG. 2 a further, partially cutaway, perspective view of the steering column from FIG. 1,

[0032] FIG. 3 a longitudinal section through the steering column from FIG. 1, in the normal operating state before a crash,

[0033] FIG. 4 a longitudinal section through the steering column from FIG. 3, in the state after a crash,

[0034] FIG. 5 the cable mounting of the steering column in a view similar to FIG. 3, in an enlarged detail view and in a first embodiment,

[0035] FIG. 6 the cable mounting of the steering column in a view similar to FIG. 3, in a second embodiment,

[0036] FIG. 7 the cable mounting of the steering column in a view similar to FIG. 3, in a third embodiment,

[0037] FIG. 8 a second embodiment of a steering column according to the invention, in a diagrammatic view from below,

[0038] FIG. 9 an enlarged detail view of FIG. 8 in the normal operating state before a crash,

[0039] FIG. 10 an enlarged detail view similar to FIG. 8, in the state after a crash.

EMBODIMENTS OF THE INVENTION

[0040] In the various figures, the same parts always carry the same reference signs and therefore are usually only cited or mentioned once.

[0041] FIG. 1 shows, in an oblique view from the top left, a steering column 1 according to the invention in a perspective view from the rear (relative to the direction of travel of a motor vehicle (not shown)), while FIG. 2 shows an oblique view from below.

[0042] The steering column 1 comprises a casing unit 2 in which a steering spindle 3 is mounted so as to be rotatable about its longitudinal axis L extending in the longitudinal direction, and which at its rear end has a fastening portion 31 for fastening a steering wheel (not shown). The casing unit 2 comprises an inner casing 21 which is mounted coaxially in an outer casing 22 so as to be telescopically displaceable in the longitudinal direction, as indicated by the double arrow.

[0043] A carrier unit 4 comprises a bracket 41 which has a fastening means 42 for connection to a body (not shown), and two side cheeks 43 and 44 which lie opposite each other transversely to the longitudinal axis L and between which the casing unit 2 is held.

[0044] As part of the carrier unit 4, a pivot bearing 45 is arranged spaced towards the front in the front end region of the outer casing 22, and has a bearing opening 46 through which a bearing bolt 48 extends in the direction of a pivot axis S, which lies horizontally and transversely to the longitudinal axis L. Pivoting about this pivot axis S allows a height adjustment of the casing unit 2 upward or downward in height direction H relative to the bracket 41, as indicated by the correspondingly marked double arrow, wherein accordingly the casing unit 2 is moved up or down between the side cheeks 43 and 44.

[0045] In FIG. 2, the side cheek 44 and a part segment of the outer casing 22 facing the observer have been omitted for greater clarity.

[0046] A clamping device 5, which is arranged on the carrier unit 4 (formed as a bracket), has a clamping bolt 51 which extends transversely to the longitudinal axis L through longitudinal holes 47 running substantially in the height direction H, in the two side cheeks 43, 44. At an end facing the observer in FIG. 1, a clamping lever 52 is arranged on the clamping bolt 51, with an abutment 53 at the other end which is supported from the outside against the side cheek 44.

[0047] The clamping bolt 51 cooperates with a clamping mechanism 54, for example a mechanism with a cam, wedge plate or tilt lever, which is supported from the outside on the side cheek 43 and, by means of the clamping lever 52, converts a rotation of the clamping bolt 51 into a transversely oriented tensile force with which the clamping bolt 51 clamps the two side cheeks 43 and 44 against each other and hence against the outside of the outer casing 22, whereby the casing unit 2 is fixed to the carrier unit 4 by force fit in the fixing position. At the same time, the applied clamping force clamps the inner casing 21 coaxially by force fit in the outer casing 22, so the longitudinal position is also fixed. For this, the outer casing 22 has a slot 220 in the direction of the longitudinal axis L, wherein the width of the slot 220 narrows as the clamping mechanism 54 is applied, and hence the outer casing acts as a clamp and holds the inner casing 21 in the fixing position.

[0048] A cable mounting 6 according to the invention is attached to the bottom of the inner casing 21, and in the example shown has the basic shape of a longitudinally elongate, U-shaped profile which is open towards the outside. The cable mounting 6 has at least one fastening element 61, by means of which a cable 62 can be fixed to the cable mounting 6, for example by force fit, form fit or substance bonding, or combinations thereof.

[0049] The cable mounting 6 has a longitudinal slot 63 extending in the longitudinal direction, through which passes the clamping bolt 51. The longitudinal slot 63 has an adjustment portion 631 and a deformation portion 632. The adjustment portion 631 has a length in the longitudinal direction which corresponds to the maximum length adjustment range of the inner casing 21 relative to the outer casing 22. In the adjustment portion 631, the longitudinal slot 63 has a greater width than the diameter of the clamping bolt 51 which is situated in the longitudinal slot 63, so that the clamping bolt 51 can be moved therein in the longitudinal direction unhindered, so that in normal operation, the inner casing 21 is freely positionable within the length adjustment range for length adjustment, as indicated in FIG. 3 by the double arrow. In the deformation portion 632 which adjoins the adjustment portion 631 at the rear, the longitudinal slot 63 has a smaller width than the diameter of the portion of the clamping bolt 51 which is situated in the longitudinal slot 63.

[0050] In a crash, the crash force acting forward in the direction of the longitudinal axis L on the steering spindle 3 and hence on the inner casing 21 is so great that the clamping force is overcome and the inner casing 21 is moved forward relative to the carrier unit 4 by a crash travel C beyond the proposed length adjustment range, as depicted in FIG. 4.

[0051] Thus the clamping bolt 51 is moved into the deformation portion 632 adjoining the adjustment portion 631, wherein the clamping bolt 61 widens the deformation portion 632 plastically, i.e. bends or crushes the side edges. The deformation work performed effects energy absorption.

[0052] The energy absorption characteristic may be predefined by the shape of the deformation portion 632, namely the curve of the width over the crash travel C. Thus the deformation portion 632 shown in FIG. 5 has a constant, smaller width B than the diameter of the portion of the clamping bolt 51 situated in the longitudinal slot 63, so that a constant energy absorption is achieved over the crash travel C, i.e. the length of the deformation portion 632.

[0053] In FIG. 6, the deformation portion 632 has a ramp-like or wedge-shaped contour, whereby the width diminishes continuously towards the front, and accordingly the energy absorption rises progressively when, in a crash, the clamping bolt moves along the crash path C into the deformation portion 632 which tapers in a wedge shape, and hence progressively displaces plastically ever more material.

[0054] FIG. 7 shows a further variant in which the width of the deformation portion 632 initially diminishes along the crash path C and then increases again, whereby the energy absorption initially rises and diminishes again towards the end of the crash process, so that a gentler deceleration occurs.

[0055] The exemplary embodiments depicted present the technical teaching that the change in width of the longitudinal slot 63 over the crash path determines the crash characteristic, and hence gives the person skilled in the art an effective means for adapting the crash characteristic (force-travel curve) according to the requirements.

[0056] FIGS. 8, 9 and 10 show a steering column 1 according to the invention in a second embodiment. The cable mounting 6 may be configured similarly, namely with a basic form of a U-shaped profile which is fixed in its back region to the inner casing 21, so that the profile opening at the bottom faces the observer in FIGS. 8, 9 and 10. In the depictions of FIGS. 8, 9 and 10, the slot 220 of the outer casing 22, which narrows on application of the clamping device 5, is clearly evident. The cable mounting 6 protrudes at least partially into the slot 220, depending on the position which the inner casing 21 takes relative to the outer casing 22. Additionally or alternatively to the energy absorption mechanisms explained with reference to FIGS. 1 to 7, the outer casing 21 here has a deformation element with deflection jaws 7, which protrude transversely from the side into the movement cross-section of the cable mounting 6 and form a constriction of the slot 220. In normal operation, the inner casing 21 can be telescopically adjusted in the longitudinal direction relative to the outer casing 22, as shown in FIG. 9. If however a high force acts in a crash, the cable mounting 6 is forced between the deflection jaws 7 with plastic deformation, as indicated in FIG. 10 by the arrow pointing to the left there, creating a deformed portion 64 to the left of the deflection jaws 7 in FIG. 10. The amount and curve of the energy absorption may be defined by the cross-sectional profile of the cable mounting 6 and the ratio of deformation between the deflection jaws or jaw 7. It is also possible and conceivable to split, cut away or otherwise plastically deform the cable mounting 6 on passage of the deformation element.

[0057] It is furthermore possible to implement a secondary energy absorption device by means of the carrier unit 4. For this, the fastening means 42 may be configured as a sliding shoe or capsule with longitudinal holes or similar extending in the longitudinal direction, which in a crash allow the carrier unit 4 to move forward relative to the body fastening points, i.e. move the entire steering column 1 moves forward relative to the body. For energy absorption, the bearing opening 46 formed in the pivot bearing 45 may also be configured as a longitudinal slot and have a deformation portion 49, as known for example from DE 10 2012 111 890 B3.

[0058] The cable mounting 6 may preferably be formed as a sheet metal part which may be connected to the inner casing 21, preferably by substance bonding and/or form fit, for example by a weld connection or by riveting, tox clinching, flanging or similar.

[0059] It is also conceivable and possible, as an alternative or in addition to the embodiment shown, to provide a cable mounting 6 with energy absorption according to the invention on the outer casing 22 and/or on the carrier unit 4.

LIST OF REFERENCE SIGNS

[0060] 1 Steering column [0061] 2 Casing unit [0062] 21 Inner casing [0063] 22 Outer casing [0064] 220 Slot [0065] 3 Steering spindle [0066] 31 Fastening portion [0067] 4 Carrier unit [0068] 41 Bracket [0069] 42 Fastening means [0070] 43, 44 Side cheeks [0071] 45 Pivot bearing [0072] 46 Bearing opening [0073] 47 Longitudinal holes [0074] 48 Bearing bolt [0075] 49 Deformation portion [0076] 5 Clamping device [0077] 51 Clamping bolt [0078] 52 Clamping lever [0079] 53 Abutment [0080] 54 Clamping mechanism [0081] 6 Cable mounting [0082] 61 Fastening element [0083] 62 Cable [0084] 63 Longitudinal slot [0085] 631 Adjustment portion [0086] 632 Deformation portion [0087] L Longitudinal axis [0088] S Pivot axis [0089] H Height direction [0090] C Crash travel