ADJUSTMENT DRIVE FOR A STEERING COLUMN, AND STEERING COLUMN FOR A MOTOR VEHICLE

Abstract

An adjustment drive for a steering column for a motor vehicle may include a housing that is able to be connected to the steering column, in which a gear wheel that is able to be rotatingly driven by a motor is mounted in a bearing assembly so as to be rotatable about a spindle axis, and on which a threaded spindle that engages in a spindle nut is axially supported in a direction of the spindle axis. To enable less complexity in manufacturing and assembling, an energy absorbing installation is disposed between the threaded spindle and the housing. When repositioning the threaded spindle relative to the housing in the direction of the spindle axis, the energy absorbing installation is configured to absorb kinetic energy.

Claims

1.-19. (canceled)

20. An adjustment drive for a steering column for a motor vehicle, comprising: a housing that is connectable to the steering column; a gear wheel that is configured to be rotatably driven by a motor about a spindle axis, the gear wheel being mounted in a bearing assembly in the housing; a threaded spindle that engages in a spindle nut and is axially supported by or in the housing in a direction of the spindle axis; and an energy-absorbing installation disposed between the threaded spindle and the housing, wherein the energy-absorbing installation is configured to absorb kinetic energy when the threaded spindle is repositioned relative to the housing in the direction of the spindle axis

21. The adjustment drive of claim 20 wherein the energy-absorbing installation includes an energy-absorbing element.

22. The adjustment drive of claim 20 wherein the energy-absorbing installation is configured to interact with the bearing assembly and the housing.

23. The adjustment drive of claim 20 wherein the housing is configured to be tubular in the direction of the spindle axis, wherein the bearing assembly is received coaxially in the housing.

24. The adjustment drive of claim 20 comprising a retaining element disposed between a thrust bearing element of the bearing assembly and the housing.

25. The adjustment drive of claim 24 wherein the retaining element includes an energy-absorbing element.

26. The adjustment drive of claim 24 wherein the retaining element has a contact portion that is braced relative to the housing.

27. The adjustment drive of claim 24 wherein the thrust bearing element includes a forming die that interacts with the retaining element and includes a forming portion.

28. The adjustment drive of claim 27 wherein the forming portion is a first forming portion, the thrust bearing element including a second forming portion that is spaced apart from the first forming portion, wherein the first and second forming portions are configured such that the retaining element, upon a first forming about the first forming portion, is configured to be formed in a second forming about the second forming portion.

29. The adjustment drive of claim 28 wherein the retaining element includes a retaining portion that is inclined relative to the thrust bearing element and extends from the first forming portion up to a contact portion of the retaining element that is braced relative to the housing, wherein the retaining portion includes a sub-portion that is configured to be formed about the second forming portion relative to the thrust bearing element so as to extend in a more inclined manner from the second forming portion up to the contact portion.

30. The adjustment drive of claim 28 wherein the retaining element is configured as a retaining ring, wherein the thrust bearing element is configured as a thrust bearing ring, wherein the first forming portion and the second forming portion include bending edges that are encircling in a circumferential direction and are directed toward the retaining ring.

31. The adjustment drive of claim 20 wherein the housing includes at least one of: an internal cross section that converges so as to taper in the direction of the spindle axis; a slot that extends in the direction of the spindle axis; or a partial variation in terms of wall thickness.

32. The adjustment drive of claim 20 wherein the energy-absorbing installation includes a bending lug or a tear-away lug.

33. The adjustment drive of claim 20 wherein the energy-absorbing installation includes a hollow member that is coaxial with the spindle axis and is plastically compressible axially in the direction of the spindle axis.

34. The adjustment drive of claim 20 wherein the housing includes a hollow member that is coaxial with the spindle axis and is plastically compressible axially in the direction of the spindle axis.

35. The adjustment drive of claim 20 wherein the gear wheel is connected in a rotationally fixed manner to the spindle nut or in a rotationally fixed manner to the threaded spindle.

36. The adjustment drive of claim 20 comprising a predetermined breaking element disposed between the threaded spindle and the housing.

37. A steering column comprising: a first steering column component and a second steering column component that are adjustable relative to one another in a direction of a spindle axis; and the adjustment drive of claim 20, wherein the adjustment drive includes the housing that by way of a connection means is attachable to the first steering column component and is supportable in the direction of the spindle axis, wherein the threaded spindle of the adjustment drive is supported on the housing in the direction of the spindle axis, the threaded spindle being attachable to the second steering column component and supportable in the direction of the spindle axis.

38. The steering column of claim 37 wherein the first and second steering column components comprise at least three casing tubes that are adjustable relative to one another in a direction of a steering column axis.

Description

DESCRIPTION OF THE DRAWINGS

[0046] Advantageous embodiments of the invention will be explained in more detail hereunder by means of the drawings in which:

[0047] FIG. 1 shows a steering column according to the invention in a schematic perspective view;

[0048] FIG. 2 shows an adjustment drive according to the invention of a steering column according to FIG. 1 in a stand-alone perspective view;

[0049] FIG. 3 shows a longitudinal section through the adjustment drive according to FIG. 2 in the normal operating state;

[0050] FIG. 4 shows the adjustment drive according to FIG. 3 after the event of a crash;

[0051] FIG. 5 shows a longitudinal section through an adjustment drive in a second embodiment in a view as in FIG. 2 and in the normal operating state;

[0052] FIG. 6 shows a longitudinal section through an adjustment drive in a third embodiment in a view as in FIG. 2 and in the normal operating state;

[0053] FIG. 7 shows a detailed view of a longitudinal section through an energy-absorbing installation of an adjustment drive in the normal operating state;

[0054] FIG. 8 shows a view as in FIG. 7 during the event of a crash;

[0055] FIG. 9 shows a view as in FIG. 8 after the event of a crash;

[0056] FIG. 10 shows a longitudinal section through an adjustment drive in a fourth embodiment in a view as in FIG. 2 and in the normal operating state;

[0057] FIG. 11 shows an adjustment drive according to FIG. 3 after the event of a crash;

[0058] FIG. 12 shows a schematic perspective view of an adjustment drive in a fifth embodiment;

[0059] FIG. 13 shows a longitudinal section through the adjustment drive according to FIG. 12 in the normal operating state;

[0060] FIG. 14 shows a schematic perspective view of an adjustment drive in a sixth embodiment;

[0061] FIG. 15 shows a longitudinal section through the adjustment drive according to FIG. 14 in the normal operating state;

[0062] FIG. 16 shows the adjustment drive according to FIG. 15 after the event of a crash; and

[0063] FIG. 17 shows a longitudinal section through an adjustment drive in a seventh embodiment in a view as in FIG. 2 and in the normal operating state.

EMBODIMENTS OF THE INVENTION

[0064] In the various figures, identical parts are always provided with the same reference signs and therefore are in each case typically only identified or mentioned once.

[0065] FIG. 1 shows a steering column 1 according to the invention which has an actuator unit 2 in a view which in terms of the travel direction is from obliquely behind. The actuator unit 2 comprises a casing unit 3 which has an external casing tube 31, an intermediate casing tube 32, and an internal casing tube 33. The casing tubes 31, 32 and 33 are disposed coaxially so as to be telescopically displaceable inside one another in the longitudinal direction, this corresponding to the axial direction of the longitudinal axis L, as is indicated by a double arrow.

[0066] A steering spindle 4 which at the rear end thereof has a connector portion 41 for attaching a steering wheel, not illustrated, is mounted so as to be rotatable about the longitudinal axis L in the casing unit 3.

[0067] The casing unit 3 is held in a two-part support unit 2 which has fastening means 51 for attaching to a vehicle body not illustrated.

[0068] An adjustment drive 6 for the longitudinal adjustment, also referred to as a longitudinal adjustment drive, has a spindle drive having a spindle nut 66 and a threaded spindle 62 which is screwed into the latter, the spindle nut 66 and the threaded spindle 62 being able to be rotatingly driven relative to one another by an electric motor 63. The threaded spindle 62 by way of the spindle axis S thereof extends parallel to the longitudinal axis L and by way of a connection element configured as a clevis 621 is connected to the internal casing tube 33, and axially supported, that is to say supported in the direction of the spindle axis S. The spindle nut 66 by way of the adjustment drive 6 is likewise axially supported in the longitudinal direction, the latter corresponding to the axial direction of the longitudinal axis L, on the external casing tube 31, wherein the external casing tube 31 has a fork portion, and wherein the adjustment drive 6 can be coupled to the fork portion by way of an intervening, damping rubber element configured as a silent bush. Depending on the rotating direction, the threaded spindle 62 and the spindle nut 66 are converged or diverged by a relative rotation by means of the motor 63, as a result of which the internal casing tube 33 in the axial direction is driven into the external casing tube 31 or driven out of the latter, as is indicated by the double arrow. As a result, a longitudinal adjustment by way of which a steering wheel attached to the connector portion 41 can be moved toward the front, to the left in the illustration in FIG. 1, to a stowage position in which the internal casing tube 33 and the intermediate casing tube 32 are retracted in the external casing tube 31, that is to say inserted thereinto toward the front, or to an operating position in the operating region in which the casing tubes 31, 32 and 33 are diverged, is realized.

[0069] Alternatively, the spindle nut 66 can be supported on the internal casing tube 33, and the threaded spindle 62 can be supported on the external casing tube 31.

[0070] FIG. 2 shows the adjustment drive 6 in a stand-alone separate view. The drive unit of the adjustment drive 6 has a tubular housing 64 having a circular cross section, said housing 64 by way of the interior space thereof extending coaxially with the spindle axis S. The motor 63 is flange-fitted to the housing 64. The housing 64 has stud-shaped connection elements 65 which in the example shown project radially outward and are preferably integrally molded in the housing 64 such that said connection elements 65 project radially outward. Said connection element 65 are able to be connected with corresponding connection means on the external casing tube 31, and in axial terms preferably supported in the direction of the spindle axis S on said connection means in a form-fitting manner.

[0071] FIG. 3 shows a longitudinal section along the spindle axis S through the adjustment drive 6 in the normal operating state. The threaded spindle 62 engages in a spindle nut 66 which is connected in a rotationally fixed manner to a gear wheel 7 so as to be coaxial with the latter. The gear wheel 7 in the example shown is a worm gear with an externally encircling toothing 71 configured as a worm splining, a worm 67 meshing with the latter, said worm 67 by the motor 63 being able to be rotatably driven about a worm axis which is transverse to the spindle axis S and in the present view perpendicular to the section plane.

[0072] The gear wheel 7 in the housing 64 is mounted in bearing assemblies 72 and 73 so as to be rotatable about the spindle axis S, said bearing assemblies 72 and 73 being in each case disposed at axial and sides and in the example shown are both configured as roller bearings, specifically as angular ball bearings, having balls 74 which on both sides on the gear wheel 6 roll on encircling rolling member raceways 75 which are mutually oblique. The housing-proximal first bearing assembly 72, on the left in the drawing, has a bearing ring 76 which has a rolling member raceway 75 which lies obliquely opposite the rolling member raceway and corresponds to the latter. The bearing ring 76, so as to be axially directed away from the gear wheel 7, in the drawing to the left, by way of a thrust bearing ring 77 is supported in relation to a retaining ring 8 which forms a retaining element and is braced in the housing 64.

[0073] The spindle-proximal second bearing assembly 73, on the right in the drawing, can in principle be constructed so as to be mirror-symmetrical to the first bearing assembly 72 in terms of a mirror plane running through the gear wheel 7 so as to be perpendicular to the spindle axis S. This second bearing assembly 73 likewise has a bearing ring 76 which has a rolling member raceway 75 which is obliquely opposite the rolling member raceway and corresponds to the latter. The second bearing ring 76, in a manner directed axially away from the gear wheel 7, in the drawing to the right, by way of a second thrust bearing ring 77 is supported in relation to a second retaining ring 8 which is likewise braced in the housing 64. The gear wheel is thus mounted in the housing 64 by means of a so-called X-bearing assembly.

[0074] The gear wheel 7 in the normal operating state is rotatably mounted in a defined axial position in the bearing assemblies 72 and 73, said bearing assemblies 72 and 73 being held and supported in the axial direction of the spindle axis S by the retaining rings 8 that are braced in the interior space of the housing 64.

[0075] In the event of a crash, a high crash force F, which as is plotted in FIG. 4 is directed from the spindle site to the housing side, to the left in the drawing, acts on the spindle 62 by way of the clevis 621. A high crash force F is understood to mean forces with a value of 1000 N or more. This crash force F is transmitted from the threaded spindle 62 to the gear wheel 7 by way of the spindle nut 66, and from the gear wheel 7 transmitted to the retaining ring 8 by way of the bearing assembly 72. Correspondingly, the crash force F in the axial direction acts counter to the retaining force which as a result of the bracing is generated between the retaining ring 6 and the housing 64. When the crash force F in the event of a crash exceeds this retaining force, the connection is released and the gear wheel 7 conjointly with the threaded spindle 62 including the bearing assembly 72 is moved along the axial direction out of the meshing into the interior space of the housing 64. By virtue of the bracing between the moving retaining ring 8 and the housing 64, a friction force acts here, as a result of which kinetic energy is absorbed and converted into heat such that the threaded spindle 62 is decelerated relative to the housing 64. In this embodiment, an energy-absorbing installation 9 which according to the invention is integrated in the housing 64 of the adjustment drive 6 is formed conjointly by the retaining ring 8 and the housing 54.

[0076] The second bearing assembly 73 remains in the original position thereof in the housing, as can be seen in FIG. 4. The worm 67 is no longer operatively connected to the gear wheel 7 such that said worm 67 and said gear wheel 7 are decoupled. The thread between the spindle nut 66 and the threaded spindle 62 is conceived in such a manner that a self-locking action is present between the spindle nut 66 and the threaded spindle 62 such that it is effectively prevented that the threaded spindle 62 is forced through the spindle nut 66 and the energy-absorbing installation 9 can thus become effective according to the intended use in the event of a crash.

[0077] The second embodiment shown in FIG. 5 in a view as in FIG. 3, is additionally distinguished in that the internal cross section of the housing 64, through which the bearing assembly 72 passes in the axial direction in the event of a crash, as is shown in FIG. 4, conically tapers from the spindle side toward the housing side, thus in the direction of the crash force F, in the drawings from right to left. The diameter D in the normal operation here, in the region of the fixing of the bearing assembly 72 is constricted to a smaller final diameter d, in the example shown so as to continuously converge in a conical manner. It is achieved as a result that in the axial displacement to the position shown in FIG. 4 in the event of a crash, the friction between the retaining ring 8 and the housing increases by way of the axial displacement path in the event of a crash, the so-called crash path, as a result of which a progressive energy-absorbing characteristic can be implemented. The reduction of the diameter here can also take place in a discontinuous or irregular manner, respectively, and is not limited to a predetermined shape.

[0078] The third embodiment shown in FIG. 6 is in principle constructed like the aforementioned second embodiment, wherein the tubular housing 64 additionally has a slot 91 which continues across an axial sub-region. The radial stiffness of the housing 64 can be reduced in a defined manner by way of the size, shape and disposal of one or a plurality of slots 91 of this type, so that the effective friction in relation to the retaining ring 8, and as a result thereof the energy-absorbing characteristic, can be predefined. The slot 91 can also be used in housings 64 without a constriction of the diameter; for example, the housing 64 of the first embodiment can also be provided with one or a plurality of slots. Likewise, the shape of the slot 91 is not limited to that shape as illustrated in the third embodiment. The slot 91 can also run in an undulating or a helical manner in the circumferential direction. Furthermore alternatively or additionally to a slot, further cutouts can also be provided in the housing 64.

[0079] A refinement of the invention is illustrated in an enlarged sectional view of the bearing assembly 72 in FIGS. 7, 8 and 9, said refinement being in principle implementable in each of the previously explained embodiments, preferably having a conically converging housing 64, as in FIGS. 5 and 6.

[0080] The bearing ring 76 on that side thereof that faces the retaining ring 8 is axially supported in relation to the thrust bearing ring 77. The thrust bearing 77 on the end side thereof that faces the retaining ring 8, on the left in the drawings, has a forming die having a first forming element configured as an encircling bending edge 771, and a second forming element likewise configured as an encircling bending edge 772. The bending edge 772 is spaced apart from the bending edge 771 in a radially outward manner, and in an axial manner in the direction toward the gear wheel 7. The retaining ring 8 has a central support ring 81 which bears axially on the thrust bearing ring 77, a retaining portion 82 from said central support ring 81 extending radially outward from the first bending edge 771 so as to be inclined in relation to the spindle axis S. The retaining portion 82 on the outer end thereof has a contact portion 83 which can have a bead which encircles the latter at least in portions, or a retaining edge, for example, said contact portion 83 from the inside bearing on the internal wall 641 of the housing 64 by way of said bead or retaining edge. As a result of the retaining portion 82 potentially being configured as a flexurally elastic flexible tongue, preferably integral to the retaining ring 8 as a stamped-and-bent formed part of spring steel sheet, the contact portion 83 is resiliently preloaded, as a result of which the retaining ring 8 is elastically braced in the housing 64.

[0081] In the normal operating state according to FIG. 7, the retaining portion 82, so as to be inclined in relation to the thrust bearing ring 77, extends from the first bending edge 771 up to the housing 64, specifically in a region having the larger diameter D. The second bending edge 772 is not in contact with the retaining ring 8.

[0082] FIG. 8 shows the situation in the event of a crash, in which the bearing assembly 72, including the retaining ring 8, in the preferably conically converging housing 64 is axially repositioned in the operative direction of the crash force F into an interior region having a smaller diameter d, as is indicated by the arrow. As a result thereof, the contact portion 83 is pushed radially inward, and the retaining portion 82 is more heavily inclined in relation to the spindle axis S. As a result of the deformation by bending about the first bending edge 771 generated here, the contact portion 83 is elastically tensioned and pushed more firmly against the housing 64, and the friction force increases as a result of which the absorption of energy is increased. The inclination increases until the retaining portion 82 contacts the second bending edge 772. As a result thereof, the effective length of the retaining portion 82 is reduced, and the effective stiffness of the retaining portion 82, the latter still being able to flex, is thus increased, because the shorter the effective length of the retaining portion the stiffer the effective length of the retaining portion.

[0083] When the retaining ring 8 is repositioned even further into the conical region during the crash, in the illustration of FIGS. 5 and 6 to the left, the contact portion 83 is pushed even farther radially inward. As a result of the retaining portion 82 already bearing on the second bending edge 772 and as an entity not being able to be inclined farther inward relative to the first bending edge 771, the outer sub-portion 84 of the retaining portion 82, the former extending from the second bending edge 772 up to the contact portion 83, is bent radially inward about the second bending edge 772, as is indicated by the curved arrow. In other words, the retaining portion 62 is bent once again about the second bending edge 772 such that the outer sub-portion 62 is even more inclined in relation to the spindle axis. As a result thereof, the effective elastic length of the flexible tongue forming the retaining portion is reduced, and a result thereof the elastic force of the contact portion 83 in relation to the housing 64 is yet again increased. Accordingly, the absorption of energy is further increased.

[0084] A progressively increasing energy-absorbing characteristic can be implemented in this way by the forming die having the bending edges 771 and 772 in interaction with the deformable retaining ring 8, and preferably with the conically converging housing 64.

[0085] A further refinement is shown in FIGS. 10 and 11 in the same view as in FIGS. 3 and 4, specifically likewise in the normal operating state and after a crash. In the normal operating state according to FIG. 10, the retaining ring 8 of the bearing assembly 72, at least in the outer peripheral region thereof where said retaining ring 8 by way of the contact portion 83 is braced in relation to the housing 64, has a shape which is inclined away from the thrust bearing ring 77. In other words, the retaining element 8 can comprise a conical annular disk in the shape of a tapered sleeve which, directed away from the trust bearing element 77, conically widens and by way of contact elements 83 of said conical annular disk on the external circumference thereof bears on the internal wall of the tubular housing 64. When viewed from the thrust bearing element 77, the retaining element 8, in the region of a contact portion 83 on the external circumference of said retaining element 8, bears on the housing 64 at an acute angle α, thus α<90°. For improved clarity, α is plotted against the spindle axis S.

[0086] When the crash force F exceeds a predefined limit value, the inner region of the retaining ring 8 is pushed in in the axial direction, the direction of the crash force F, through the outer peripheral region supported on the housing 64, such that the conical annular disk of the retaining ring 8 is elastically inverted and the tapered sleeve shape now widens in the axially opposite direction, toward the thrust bearing ring 77, the retaining ring 8 in other words being folded over toward the thrust bearing ring 77. When viewed from the thrust bearing element 77, the retaining ring 8 after folding over, in the region of a contact portion 83 on the external circumference thereof bears on the housing 64 at an obtuse angle β, thus β>90°. As a result thereof, the subsequent relative movement can take place while absorbing energy.

[0087] The folding retaining ring 8 forms a threshold switch which releases a relative movement only when a limit value of the force acting thereon is exceeded. Alternatively or additionally, predetermined breaking elements such as shear rivets or the like which break when a force limit value is exceeded and release a relative movement for activating an energy-absorbing installation can.

[0088] FIG. 12 in a perspective view shows a further embodiment of an adjustment drive 6, and FIG. 13 shows a longitudinal section in the normal operating state as in FIG. 3.

[0089] The energy-absorbing installation 9 as energy-absorbing elements has two bending strips 92 which by way of incorporated longitudinal slots 93 are configured so as to be integral to the wall of the housing 64. Alternatively, an embossing can be provided instead of the longitudinal slots 93, so as to provide a tear-away lug. As can be seen in FIG. 12, the one end 921 of the bending strip 92 transitions integrally to the housing 64, and the bending strip 92 by way of a bend 923 of approximately 180° runs radially into the interior of the housing up to the free second end 922, the latter consequently having substantially the same direction as the first end 921. The free end 922 is connected to a transmission piece 94 which from the outside, on the end side that faces away from the gear wheel, is axially supported in relation to the bearing assembly 72, for example in relation to the retaining ring 8. When a crash force F acts on the threaded spindle 62, the bearing assembly 72 is repositioned in the axial direction in the housing 64, as has been described above. The free end 922 here is entrained by the transmission piece 94 in the direction toward the fixed end 921, and the bending strip 92 is continuously bent about the bend 923. As a result of the deformation work performed here, kinetic energy is absorbed and the threaded spindle 62 is decelerated relative to the housing 64. The coupling between the transmission piece 94 and the free end 922 in a further embodiment can take place by means of a coupling installation which is configured as a pyrotechnic switch, for example, so as to couple or decouple the bending strips such that either one of the bending strips 92, both bending strips 92 or none of the bending strips 92 is deformed in the event of a crash.

[0090] A further embodiment is illustrated in a perspective view in FIG. 14, and in the normal operating state and after a crash illustrated in sectional views in FIGS. 15 and 16 as in FIGS. 3 and 4.

[0091] The tubular housing 64 here, in a portion between the connection elements 65 and the gear wheel 7, has a corrugated tube 95 which has a plurality of axially successive, radially molded corrugations 951 which preferably encircle the circumference, said corrugated tube 95 forming an energy-absorbing element. The corrugated tube 95 is disposed so as to be coaxial with the spindle axis S and can be connected to the housing 64, or be configured so as to be integral to the latter. The threaded spindle 62 in axial terms can be at least partially disposed in the corrugated tube 95, as is illustrated.

[0092] In the event of a crash, the corrugated tube 95, in the direction of the crash force F acting in this instance, is axially plastically compressed in the direction of the spindle axis S, as is illustrated in FIG. 6, as a result of which kinetic energy is absorbed.

[0093] FIG. 17 in a sectional view as in FIG. 3 shows a further embodiment. Like the embodiment shown in FIGS. 3 and 4, this further embodiment has a tubular housing 64. A corrugated tube 96 which has a multiplicity of encircling corrugations and is supported between the bearing assembly 72 and an axial thrust bearing 68 on that end of the housing 64 that faces away from the bearing assembly 72 is disposed as an energy-absorbing element in the housing 64. In the event of a crash, the bearing assembly 72 is moved in the direction toward that end of the housing 64 that faces away from the bearing assembly 72, as is shown in FIG. 4, as a result of which the corrugated tube 96 is axially compressed and absorbs kinetic energy. A progressive crash characteristic can be implemented in that the compressed corrugated tube 96 radially bears on the internal wall of the housing 64, this during further compression thus leading to an increase in terms of the crash force.

[0094] The energy-absorbing installations 9 shown in FIGS. 12 to 17 can be combined with one another and also combined with the energy-absorbing installations 9 according to FIGS. 3 to 11, the latter being implemented by the retaining ring 8. A folding retaining ring 8 according to FIGS. 10 and 11 as a trigger installation for activating an energy-absorbing installation 9 can be combined with all of the other embodiments.

LIST OF REFERENCE SIGNS

[0095] 1 Steering column [0096] 2 Actuator unit [0097] 3 Casing unit [0098] 31 External casing tube [0099] 32 Intermediate casing tube [0100] 33 Internal casing tube [0101] 34, 35 Detent [0102] 4 Steering spindle [0103] 41 Connector portion [0104] 5 Support unit [0105] 51 Fastening means [0106] 6 Adjustment drive [0107] 62 Threaded spindle [0108] 621 Clevis [0109] 63 Motor [0110] 64 Housing [0111] 65 Connection element [0112] 66 Spindle nut [0113] 67 Worm [0114] 68 Thrust bearing [0115] 7 Gear wheel [0116] 71 Toothing [0117] 72, 73 Bearing assembly [0118] 74 Balls [0119] 75 Rolling member raceway [0120] 76 Bearing ring [0121] 77 Thrust bearing ring [0122] 771 Bending edge [0123] 772 Bending edge [0124] 8 Retaining ring [0125] 81 Support ring [0126] 82 Retaining portion [0127] 83 Contact portion [0128] 84 Sub-portion [0129] 9 Energy-absorbing installation [0130] 91 Slot [0131] 92 Bending strip [0132] 921 First end [0133] 922 Second end [0134] 923 Bend [0135] 93 Longitudinal slots [0136] 94 Transmission piece [0137] 95 Corrugated tube [0138] 96 Corrugated tube [0139] L Longitudinal axis [0140] S Spindle axis [0141] F Crash force