STEERING COLUMN FOR A MOTOR VEHICLE, AND ENERGY ABSORPTION DEVICE

Abstract

A steering column may include a sleeve unit in which a steering spindle rotatably mounted about a longitudinal axis, which sleeve unit is accommodated in a supporting unit so as to be displaceable in a longitudinal direction. An energy absorption device may be fitted between the supporting unit and the sleeve unit. The energy absorption device may include first and second bending elements that each comprise an elongate input limb positioned parallel to the longitudinal direction and connected at a free end to the supporting unit or the sleeve unit, and merges at another end into a bend to which a fixed limb is connected. The fixed limb may be connected to the other of the supporting unit or the sleeve unit. The second bending element may be formed in a mirror-inverted manner relative to the first bending element and may be positioned mirror-symmetrically adjacent to the first bending element.

Claims

1.-12. (canceled)

13. A steering column for a motor vehicle comprising: a supporting unit configured to be connected to a body of the motor vehicle; a sleeve unit in which a steering spindle is rotatably mounted about a longitudinal axis of the steering spindle, the sleeve unit being accommodated in the supporting unit so as to be displaceable in a longitudinal direction parallel to the longitudinal axis of the steering spindle; and an energy absorption device disposed between the supporting unit and the sleeve unit, the energy absorption device comprising first and second bending elements that each comprise an elongate input limb that is parallel to the longitudinal direction and a free end and another end that merges into a bend to which a fixed limb is connected, wherein either the free end is connected to the supporting unit and the fixed limb is connected to the sleeve unit, or the free end is connected to the sleeve unit and the fixed limb is connected to the supporting unit, wherein the second bending element mirrors the first bending element and is disposed adjacent to the first bending element.

14. The steering column of claim 13 wherein the second bending element is formed in a mirror-inverted manner with respect to the first bending element and is positioned mirror-symmetrically adjacent to the first bending element.

15. The steering column of claim 13 wherein outer sides of the elongate input limbs of the first and second bending elements face away from the bends and lie parallel against one another.

16. The steering column of claim 13 wherein the elongate input limbs of the first and second bending elements are connected to one another by way of tearing-off elements.

17. The steering column of claim 13 wherein the fixed limbs comprise fastening elements for connecting the fixed limbs to the supporting unit or the sleeve unit.

18. The steering column of claim 17 wherein the fastening elements of the first and second bending elements are connected to each other perpendicularly to a mirror plane extending between the first and second bending elements.

19. The steering column of claim 17 wherein the fastening elements are connected to a bridge element.

20. The steering column of claim 13 wherein the fixed limbs extend to the free ends of the elongate input limbs and are connected to the elongate input limbs via breakaway elements.

21. The steering column of claim 13 wherein the energy absorption device is disposed between boundary elements that extend parallel to the longitudinal axis adjacent to the fixed limbs.

22. The steering column of claim 13 wherein each of the first and second bending elements is configured from a bending wire or a bending strip.

23. The steering column of claim 13 wherein each of the first and second bending elements is configured from a punched part or a bent part.

24. The steering column of claim 13 wherein the first and second bending elements are coated with a coating.

25. An energy absorption device for a steering column of a motor vehicle, the energy absorption device configured to be coupled between a supporting unit and a sleeve unit that is displaceable in a longitudinal direction relative thereto, the energy absorption device comprising first and second bending elements that each include an elongate input limb that is disposed parallel to the longitudinal direction and is connected at a free end to the supporting unit or the sleeve unit, wherein the elongate input limbs of the first and second bending elements are parallel to each other.

26. The energy absorption device of claim 25 wherein the second bending element is formed in a mirror-inverted manner with respect to the first bending element and is positioned mirror-symmetrically adjacent to the first bending element.

Description

DESCRIPTION OF THE DRAWINGS

[0029] Advantageous embodiments of the invention are explained in more detail below with reference to the drawings, in which, in detail:

[0030] FIG. 1 shows a first embodiment of a steering column according to the invention in a schematic perspective view,

[0031] FIG. 2 shows the adjustment unit of the steering column according to FIG. 1,

[0032] FIG. 3 shows the adjustment unit of the steering column according to FIG. 1,

[0033] FIG. 4 shows the adjustment unit of the steering column according to FIG. 1 in a further embodiment,

[0034] FIG. 5 shows the adjustment unit of the steering column according to FIG. 3 in a partially pulled-apart state,

[0035] FIG. 6 shows the energy absorption device of the steering column according to FIGS. 1-3 and 5 in a schematic perspective view with pulled-apart bending elements,

[0036] FIG. 7 shows the energy absorption device according to FIG. 6 in a further perspective view,

[0037] FIG. 8 shows the energy absorption device according to FIG. 6 in a top view in the radial direction with respect to the longitudinal axis,

[0038] FIG. 9 shows a second embodiment of a steering column according to the invention in a schematic perspective view,

[0039] FIG. 10 shows the adjustment unit of the steering column according to FIG. 9,

[0040] FIG. 11 shows the adjustment unit according to FIG. 9 in a partially pulled-apart state,

[0041] FIG. 12 shows the energy absorption device according to FIGS. 9 to 11 in a top view in the radial direction with respect to the longitudinal axis,

[0042] FIG. 13 shows a perspective view of the energy absorption device according to FIG. 12,

[0043] FIG. 14 shows the energy absorption device of the steering column according to FIGS. 9 to 11 in a schematic perspective view with pulled-apart bending elements,

[0044] FIG. 15 shows a further perspective view of the energy absorption device according to FIG. 12,

[0045] FIG. 16 shows a third embodiment of a steering column according to the invention in a schematic perspective view,

[0046] FIG. 17 shows the adjustment unit of the steering column according to FIG. 16.

EMBODIMENTS OF THE INVENTION

[0047] In the various figures, identical parts are always provided with the same reference signs and are therefore generally also only named or mentioned once in each case.

[0048] FIG. 1 shows a steering column 1 according to the invention schematically in a perspective view obliquely from the rear (with respect to the direction of travel of a motor vehicle which is not illustrated).

[0049] The steering column 1 has an adjustment unit 2, with a sleeve unit 21 which is designed as a steering column tube 21 and in which a steering spindle 22 is mounted so as to be rotatable about the longitudinal axis 23. (The designations steering column tube 21 and sleeve unit 21 are used synonymously below). At its rear end with respect to the direction of travel, the steering spindle has a fastening portion 24 for the fitting of a steering wheel (not illustrated).

[0050] For the designation of directional details, it is established by definition below that the steering spindle 22 and therefore the steering column tube 21 or the adjustment unit 2 extend from the steering-wheel-side end, where the fastening portion 24 is located, forwards in the longitudinal direction L parallel to the longitudinal axis 23 to the steering-wheel-remote or steering-gear-side end 25, which is indicated by the forwardly pointing arrow L.

[0051] The sleeve unit 21 is accommodated in a supporting unit 3which, depending on the design of the steering column, is also referred to as a guide box or box-section swing armso as to be displaceable parallel to the longitudinal axis 23 in and counter to the longitudinal direction L, as a result of which, firstly, an adjustment of the length of the steering column 1 can be undertaken in order to adapt the steering wheel position and, secondly, energy absorption in the event of a crash can take place. By means of a clamping device 31 which is not explained in detail and is known per se in the prior art, the adjustment unit 2 can be fixed relative to the supporting unit 3 during normal operation.

[0052] The steering column 1 can be fastened to a body (not illustrated) of a motor vehicle with a bracket 4. At the bracket 4, the supporting unit 3 is mounted so as to be pivotable about an axis 41 lying perpendicularly to the longitudinal axis 23, as a result of which the steering wheel can be adjusted vertically in both vertical directions H.

[0053] Fitted between the sleeve unit 21 and the supporting unit 3 is an energy absorption device 5 which forms a connection in the longitudinal direction L.

[0054] In the event of a crash, a large force is exerted in the longitudinal direction L on the sleeve unit 21 via the steering spindle 22 due to the fact that the driver impacts with his body forwardly against the steering wheel. The acting force is transmitted from the sleeve unit 21 in the longitudinal direction L via the energy absorption device 5 to the supporting unit 3 which is fixedly connected to the body in this direction. The operating principle of the energy absorption device 5 is based on the fact that the introduced kinetic energy is converted into plastic deformation, as a result of which energy absorption and therefore controlled braking of the driver take place. A defined breakaway force can be set here.

[0055] FIGS. 2, 3 and 4 show the adjustment unit 2 in the same perspective as FIG. 1, wherein the supporting unit 3 has been omitted for better clarity.

[0056] The energy absorption device 5 has two bending elements 51 and 52 which, according to the invention, are designed in a mirror-inverted manner, specifically with respect to a mirror plane S, which is defined as the radial plane with respect to the longitudinal axis 23, i.e. the mirror plane S extends parallel to the longitudinal axis 23, wherein the longitudinal axis 23 lies in the mirror plane S. For clarification, the position of the mirror plane S is shown by dashed lines in FIG. 3.

[0057] The bending elements 51 and 52 comprise the identical functional elements in a mirror-inverted arrangement in each case, as can be seen with reference to the enlarged illustrations in FIGS. 6, 7 and 8, wherein FIG. 8 shows a view of the fully fitted energy absorption element 5 in the radial direction with respect to the longitudinal axis, and FIGS. 6 and 7 show perspective views in which the two bending elements 51 and 52 are pulled apart perpendicularly from the mirror plane S.

[0058] The bending elements 51 and 52 each have an elongate input limb 511, 512 which extends forwards in the longitudinal direction L from its free input-side end 512, 522. The input limb 511, 522 enters into a bend 513, 523 which is bent laterally in a manner directed away from the mirror plane S in the bending plane which is a plane parallel to the longitudinal axis 23 and perpendicular to the mirror plane S (the paper plane B in FIG. 7). The bend 513, 523, which preferably describes an arc of 180, is adjoined by the fixed limb 514, 524 which extends counter to the longitudinal direction L and on which a fastening element 515, 525 is arranged. The fastening element 515, 525 can be designed as a tab which extends from the fixed limb 514, 524 in the transverse direction towards the mirror plane S until over the input limb 511, 521, wherein the fastening element 515, 525 is not connected to the input limb 511, 512 and can comprise a fastening opening 516, 526. Over the further course, the fixed limb 514, 524 extends with a connecting region 517, 527 as far as the free end 512, 522 of the input limb 511, 521. The fixed limb 514, 524 can be connected there to the input limb 511, 521 by a breakaway element 518, 528, for example by a rivet 518, 528, as illustrated in FIG. 7.

[0059] In the case of the energy absorption device 5 which is illustrated, the two bending elements 51 and 52 lie against the mirror plane S and therefore against each other with the outer sides 519 and 529 directed against each other. The mutual positional fixing of the bending elements 51 and 52 can take place by said outer sides 519 and 529 being welded or adhesively bonded to each other or being connected to each other by means of interlocking elements, or alternatively by a connection of the fastening elements 515 and 525 to each other, for example, as in the embodiment illustrated in FIG. 2, by means of a bridge element 6 which can be fixed, for example, in an interlocking manner in the fastening openings 516 and 526, for example with studs, rivets, bolts or the like. In a further alternative which is shown in FIG. 4, the fastening elements 515 and 525 themselves can be fixedly connected to each other, for example welded.

[0060] The input limbs 511, 521 are fixedly connected at their free end 512, 522 to the sleeve unit 21, for example by means of welding or an interlocking connection.

[0061] The fixed limbs 514, 524 are connected via the bridge element 6, on which further fastening elements 61 can be formed, to the supporting unit 3 which is stationary relative to the sleeve unit 21, i.e. the fixed limbs 514, 524 are forwardly supported on the supporting unit 3 counter to the force introduced in the longitudinal direction in the event of a crash.

[0062] FIGS. 9, 10 and 11 illustrate a second embodiment of a steering column, wherein the views correspond to those from FIGS. 1, 2 and 5. The substantial difference over the first embodiment consists in the configuration of the energy absorption device 7. The same reference signs as in the first embodiment are used here for identically acting functional elements of the steering column 1 and of the energy absorption device 7.

[0063] FIGS. 9, 10 and 11 differ from FIGS. 1, 2, and 5 merely in the energy absorption device 7, and therefore the description given above can be read identically on said steering column 1 and the adjustment unit 2.

[0064] The energy absorption device 7 comprises two mirror-symmetrically arranged bending elements 71 and 72 which are constructed in a mirror-inverted manner with respect to the mirror plane S, as can be clearly seen in FIG. 12. Said bending elements basically have the same functional regions as the bending elements 51 and 52 according to FIG. 8, which is clarified by the use of the same reference signs as in FIG. 8. However, in contrast to the first variant, there is no connecting region (reference signs 517, 527 in FIG. 8) between the fixed limbs 514, 524 and the free end 512, 522 of the input limb 511, 521. Consequently, a free end 711, 721 of the fixed limb 514, 524 is located behind the fastening element 515, 525, as seen from the bend 513, 523.

[0065] The operating principle of the invention that the input limbs 511, 521 are mutually supported in the mirror plane S in the event of a force introduced in the longitudinal direction L into the free end 512, 522 in the event of a crash, is likewise realized. During deformation, the bend 513, 523 moves forwards in the longitudinal direction L with the displacement of the input limbs 511, 512 with respect to the stationary supporting unit 3, i.e. each portion of the input limb 511, 521 is gradually bent as it passes the bend 513, 523, with deformation work being performed and kinetic energy being converted or absorbed. Different characteristic curves can be represented by changing cross sections. The deformation ends when the free end 511, 521 reaches the same height as the fastening element 515, 525 and/or the bend 513, 523. The length of the deceleration path in the event of a crash and therefore the energy absorption characteristics can be predetermined in this manner by means of the length of the input limb 511, 521.

[0066] FIGS. 13 and 14 shows perspective views of the bending elements 71 and 72 which are presented in a manner pulled apart in the transverse direction with respect to the mirror plane S.

[0067] The fastening elements 515 and 525 can be designed as has been described above for the first embodiment.

[0068] A development is shown in FIG. 15 in which, in the region of the free end 512, 522 of the input limb 511, 521 and on the fixed limb 514, 524 in the region of the free end 711, 721 or of the fastening element 515, 525, connecting elements 730 are fitted on the bending elements 71, 72. At said connecting elements 730, the input limb 511, 512 can be fastened to the steering column tube 21, for example by welding.

[0069] FIGS. 16 and 17 illustrate a third variant of an energy absorption device 73 according to the invention. Said energy absorption device 73 is constructed similarly in respect of its function as explained above, wherein aspects of the first variant, namely the energy absorption device 5, and the second variant, namely the energy absorption device 7, are realized Like the first variant, the bending elements 721, 722 of the energy absorption device 73 comprise a connecting region 517, 527 which connects the fixed limb 514, 524 to the input limb 511, 521. However, the connection is not located in the end region but rather at a distance A from the free end 512, 522. This realizes an embodiment like the embodiment shown in FIGS. 6 to 8, which is adjoined within the distance A by a configuration as in the embodiment according to FIGS. 12 to 14. The specific advantages of the two embodiments can thereby be combined with one another.

[0070] It is furthermore conceivable and possible to arrange an energy absorption device 5, 7 or 73 between boundary elements 32, as illustrated by way of example in FIG. 12. The boundary elements 32 are arranged on the supporting unit 3 parallel to the longitudinal axis 23 and comprise boundary surfaces 33 which are directed counter to the mirror plane S and are parallel thereto. In the event of a crash, the fixed limb 514, 524 or the input limb 511, 512 which then runs through the bend 513, 523 can be supported against the boundary surface 33 transversely with respect to the longitudinal direction L, i.e. directed away from the mirror plane S. This avoids a deflection and an expansion of the bend 513, 523, as a result of which the energy absorption characteristics can be better controlled.

[0071] To the extent usable, all of the individual features of the invention can be combined with one another without departing from the scope of the invention.

LIST OF REFERENCE SIGNS

[0072] 1 Steering column

[0073] 2 Adjustment unit

[0074] 21 Sleeve unit (steering column tube)

[0075] 22 Steering spindle

[0076] 23 Longitudinal axis

[0077] 24 Fastening portion

[0078] 25 End

[0079] 3 Supporting unit (guide box)

[0080] 31 Clamping device

[0081] 32 Boundary element

[0082] 33 Boundary surface

[0083] 4 Bracket

[0084] 41 Axis

[0085] 5 Energy absorption device

[0086] 51, 52 Bending element

[0087] 511, 521 Input limb

[0088] 512, 522 Free end

[0089] 513, 523 Bend

[0090] 514, 524 Fixed limb

[0091] 515, 525 Fastening element

[0092] 516, 526 Fastening opening

[0093] 517, 527 Connecting region

[0094] 518, 528 Breakaway element

[0095] 519, 529 Outer side

[0096] 6 Bridge element

[0097] 61 Fastening element

[0098] 7, 73 Energy absorption device

[0099] 71, 72 Bending element

[0100] 711, 721 Free end

[0101] 721, 722 Bending element

[0102] 730 Connecting element

[0103] L Longitudinal direction

[0104] H Vertical direction

[0105] S Mirror plane

[0106] A Distance