Steering column adjustment unit

Abstract

The present invention relates to an adjustment unit (2) for a vehicle steering system (1), wherein the adjustment unit (2) is an adjustment unit (6) having an adjustment motor (8), a spindle (9), and a spindle nut (10), wherein the adjustment motor (8) is coupled to the spindle to transmit torque, and the spindle nut (10) is positioned on the spindle (9) such that the rotation of the spindle (9) causes the spindle nut (10) to move axially along the spindle (9), and the adjustment unit (6) and a pull-out device (7) fixed axially. The device (7) includes a pull-out support (11) configured to be positioned on the vehicle body in a predetermined manner, and at least one inner pull-out element (12) positioned within the pull-out support (11) in a manner that is movable in the axial direction, wherein the inner pull-out element (12) is configured to be coupled to the steering shaft (4) in a manner that is fixed in the axial direction, and an impact element (13) configured as a sleeve (13) extending coaxially with the spindle (9) between the spindle nut (10) and the inner pull-out element (11). The axial end of the sleeve (13) is positioned on the spindle nut (10) and coupled to the spindle nut (10) in a manner that is fixed in the axial direction via at least one fixing element (14), the fixing element (14) is released in the event of a predetermined impact force (F), and the sleeve (13) moves axially relative to the spindle nut (10). The outer contour (15) of the spindle nut (10) and the inner contour (16) of the sleeve (13) are configured such that, in at least some portions, the sleeve (13) becomes plasticized as a result of axial movement relative to the spindle nut (10). The present invention also relates to a steer-by-wire steering system (1) comprising such an adjustment unit (2).

Description

[Technical Field]

[0001] The present invention relates to an adjustment unit for a vehicle steering column or steering shaft, and to a steer-by-wire steering system for a vehicle having such an adjustment unit. [Background Art]

[0002] In modern steering systems or steering devices, the steering wheel can be adjusted in height and length, that is, in axial position. In such adjustment systems, the steering column elements or steering shaft elements can be moved relative to each other, for example as a telescopic arrangement. This makes it possible to move the steering wheel to a position suitable for the driver.

[0003] Furthermore, steer-by-wire steering systems are also known, in which the mechanical connection between the steering wheel and the axle steered via the steering column is omitted, and the steering of the wheels is controlled via corresponding signals. There are two main types of steer-by-wire steering systems: steer-by-wire steering systems in which the force feedback actuator is located away from the steering wheel, and steer-by-wire steering systems in which the force feedback actuator is located adjacent to the steering wheel.

[0004] Steer-by-wire steering systems in which the force feedback actuator is located away from the steering wheel use known crash elements such as metal strips that plastically deform when a defined force is exceeded. Furthermore, plastic sleeves on telescopic steering shafts that break when a predetermined force is applied are also known. In steer-by-wire steering systems in which the force feedback actuator is arranged adjacent to the steering wheel, the telescopic steering shaft can be omitted.

[0005] It is now clear that there is a further need to improve known vehicle adjustment units and / or known steer-by-wire steering systems. In particular, there is a further need to provide adjustment units and / or steer-by-wire steering systems in which force feedback actuators are located close to the steering wheel, which would allow for positioning of collision elements in a way that can reduce or even avoid lateral forces acting on them. [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] Against this backdrop, an object of the present invention is to provide improvements to the adjustment unit and / or the steer-by-wire steering system, which in particular enables the positioning of the collision element in such a way that the lateral force acting on the collision element can be reduced or even avoided. [Means for solving the problem]

[0007] These and other objectives, as described later in the following description or as recognizable to those skilled in the art, are achieved by the subject matter of the independent claims. Advantageous embodiments and further developments can be found in the dependent claims and the following description.

[0008] An adjustment unit according to the present invention for a steering system, particularly a steer-by-wire steering system, and more particularly a steer-by-wire steering system in which a force feedback actuator is in close proximity to the steering element, comprises an adjustment unit, a pull-out device, and a collision element. The adjustment unit comprises an adjustment motor, a spindle, and a spindle nut, wherein the adjustment motor is coupled to the spindle to transmit torque, and the spindle nut is positioned on the spindle such that rotation of the spindle causes axial movement of the spindle nut along the spindle. The pull-out device comprises a pull-out support configured to be positioned or fastened on the vehicle body in an axially fixed manner, particularly pivotably about a pivot axis, and at least one inner pull-out element positioned within the pull-out support in a manner axially movable relative to the pull-out support. The inner pull-out element is configured to be coupled in an axially fixed manner, particularly to an inner steering shaft. The collision element is configured as a sleeve extending coaxially with the spindle and particularly surrounding the spindle, between the spindle nut of the adjustment unit and the inner pull-out element of the pull-out device. The axial end of the sleeve is positioned on the spindle nut and coupled to the spindle nut in a manner that it is fixed axially via at least one fixing element. The fixing element is released when a predetermined impact force is applied, particularly in the case of a collision, and the sleeve moves axially relative to the spindle nut as a result of the impact force applied during the collision. The outer contour of the spindle nut and the inner contour of the sleeve are configured in a coordinated manner such that, in at least some portions, the sleeve becomes plasticized, i.e., deformed, as a result of the axial movement relative to the spindle nut.

[0009] The fixing element, which may also be called a release element, is configured to position the sleeve on the spindle nut in an axially fixed manner. Furthermore, the fixing element is configured to release the axially fixed connection between the sleeve and the spindle nut when a predetermined impact force is reached or exceeded, in order to allow the movement of the sleeve relative to the spindle nut and the associated plasticization of the sleeve. The movement path of the sleeve can be, for example, about 80 to 100 mm. The fixing element can be configured, for example, as at least one shear pin that breaks when a predetermined impact force is reached or exceeded. Furthermore, the fixing element may be implemented as a circumferential or at least partially circumferential groove or recess within the sleeve that is deformed by the impact force.

[0010] A force feedback actuator comprises a motor, or a motor and a gearbox, particularly one with a high gear ratio. The combination of motor and gearbox allows for the construction of smaller and more compact motors, because the motor needs to produce lower torque than a motor without a gearbox to achieve the same torque on the steering shaft.

[0011] An advantage of the solution according to the present invention is that the impact element can be incorporated into the pull-out device, particularly into the force flow therein. Thus, arranging the impact element substantially coaxially with the spindle makes it possible to achieve a force flow in which, during impact, lateral forces or bending moments act minimally or not at all on the impact element. Lateral forces or bending moments acting on the impact element can cause it to become immobile and / or tilt, in addition to increasing friction and / or causing lateral bending in the impact sleeve. According to the present invention, since lateral forces or bending moments act minimally or not at all on the impact element, the design of the impact element can be simplified and the drawbacks caused by lateral forces or bending moments are eliminated. This means that little or no additional components are required, and the cost of the adjustment unit can be reduced. In addition, these components can be used as forming tool elements during manufacturing.

[0012] In addition, the arrangement of the impact elements according to the present invention allows for the conversion of impact energy in the form of absorption and self-centering of the impact elements relative to the spindle nut, particularly in the case of immobilizing forces and / or tilting forces and / or offsetting forces. At the same time, when the length of the steering element is adjusted, the spindle torque can be supported by the impact elements. In addition, the spindle can be guided and / or mounted through the impact elements (and spindle nut). This may be particularly advantageous for long spindles having a length of approximately 100 mm or more, for example.

[0013] In other words, the adjustment unit according to the present invention can reduce or even eliminate the bending moment acting on the collision element, which typically arises from an undesirable lever arm. This makes it possible to omit additional components such as collision element guides, connectors, and / or deflection components.

[0014] According to one embodiment, the inner contour of the unplasticized sleeve has at least partially a deformable region and a buffer region, and the outer contour of the spindle nut is configured such that the outer contour of the spindle nut overlaps with the inner contour of the sleeve in the deformable region and is positioned particularly at a distance from the buffer region. In the event of impact, the impact force presses the impact element, i.e., the sleeve which may also be called the impact sleeve, substantially symmetrically onto the substantially fixed self-locking spindle nut. For this purpose, the spindle nut has a material that is harder than the impact sleeve, at least in the overlapping region on the outer contour.

[0015] Due to the overlap between the outer contour of the spindle nut and the inner contour of the sleeve in the deformation region, the impact sleeve is plasticized, or deformed, by the spindle nut in these regions. To prevent the impact sleeve from tearing during plasticization, the spindle nut and the impact sleeve are separated in the buffer zone so that the buffer zone can compensate for the "lost" material during plasticization of the impact sleeve in the deformation region. In other words, the plasticization of the impact sleeve in the deformation region can be said to substantially change the entire inner contour of the sleeve.

[0016] According to one embodiment, the spindle nut has a conical and / or spherical outer contour. This allows the impact sleeve to center itself when the impact force is not introduced symmetrically into the impact sleeve and at least a small lateral force may act on the impact sleeve. This prevents the impact sleeve from becoming immobile on the spindle nut and thus ensures the function of the impact element, i.e., absorption of impact energy by plasticization, even in the case of lateral and / or offset forces.

[0017] According to one embodiment, the sleeve is coupled flat to the inner drawer element at its other axial end. This ensures symmetrical force introduction across the entire front surface of the impact sleeve resting on the drawer element. The large support surface allows for the achievement of a high level of chipping rigidity.

[0018] According to one embodiment, the sleeve has a rectangular inner contour with rounded corners, and the spindle nut has a rectangular outer contour with rounded corners, and the rounded corners of the inner contour of the sleeve have a larger radius than the rounded corners of the outer contour of the spindle nut. Due to the overlapping radii, the larger radius of the impact sleeve is plasticized, i.e., deformed, by the smaller radius of the spindle nut, so that the radius of the impact sleeve after plasticization substantially corresponds to the radius of the spindle nut. However, other contour and contour pairings for the impact sleeve and spindle nut are also conceivable. In particular, it is possible to select the contour and / or contour overlap (small or large overlap) in the deformation region depending on the desired pressing force and / or impact force.

[0019] According to one embodiment, the adjustment unit, and therefore the impact element in particular, is located within the drawer device, and more specifically, within the drawer support. This arrangement is made possible, in particular, by eliminating the telescopic steering shaft in a steer-by-wire steering system where the force feedback actuator is in close proximity to the steering element, which "frees up" the equipment space within the drawer device. This means that no additional equipment space is required for the adjustment unit, and the impact element can be incorporated into the force flow generated during impact.

[0020] According to one embodiment, the adjustment unit, and therefore in particular the impact element, is located outside the drawer device, and the impact element and the spindle (and spindle nut) are arranged coaxially. The impact element is also located outside the drawer device, between the adjustment unit and the drawer device.

[0021] According to one embodiment, the sleeve is made of metal, particularly sheet metal. Sleeves formed from sheet metal material can be manufactured cost-effectively, for example, by stamping sheet metal. In addition, thin sheet metal materials have good plasticity properties. Furthermore, sleeves made from fiber composite materials can also be considered, but these are more expensive than metal.

[0022] According to one embodiment, the spindle nut is made of a metal harder than the sleeve material, at least partially, particularly on the outer circumference, i.e., on the outer contour, and more particularly on the region of the outer contour that overlaps with the inner contour of the sleeve. This ensures that, upon impact, the sleeve is plasticized by the spindle nut, but the spindle nut is not affected by the plasticization by the sleeve.

[0023] According to one embodiment, the spindle nut has a body made of plastic and a sheath made of a particularly hardened metal. The sheath can be made from a sheet metal material that is particularly deep-drawn and hardened. This means that the sheath can be manufactured cost-effectively. The plastic body of the spindle nut allows for improved noise characteristics of the adjustment unit.

[0024] A further aspect of the present invention relates to a steer-by-wire steering system, particularly a steer-by-wire steering system for a vehicle, in which a force feedback actuator is arranged adjacent to a steering element. The steering system comprises an (inner) steering shaft, a steering element, and the adjustment unit described above and below, particularly the adjustment unit according to the present invention. The steering element is coupled to the (inner) steering shaft in an axially fixed manner and so as to transmit torque. The (inner) steering shaft is also arranged within the telescopic support of the adjustment unit and coupled to the inner telescopic element in an axially fixed manner, whereby the steering shaft is arranged so as to be movable axially relative to the telescopic support via or together with the inner telescopic element. In addition, the steering shaft can rotate relative to the inner telescopic element.

[0025] According to one embodiment, the steer-by-wire steering system also comprises at least one force feedback actuator coupled to the (inner) steering shaft adjacent to the steering element so as to transmit torque. The term "adjacent to the steering element" is understood herein to mean in particular the arrangement between the adjustment unit and the steering element.

[0026] According to one embodiment, the steer-by-wire steering system further comprises a height adjustment unit for adjusting the height of the steering element. This means that the steering element can be individually adjusted for the driver in both the axial direction and the height direction.

[0027] Further measures for improving the present invention will be shown in more detail below based on the drawings, together with the description of preferred exemplary embodiments of the present invention. Brief Description of the Drawings

[0028] [Figure 1] A schematic view of a steer-by-wire steering system according to an embodiment of the present invention is shown in a perspective longitudinal sectional view. [Figure 2] A schematic diagram of an adjustment unit according to an embodiment of the present invention is shown in a perspective partial cross-sectional view. [Figure 3] A schematic diagram of an adjustment unit according to an embodiment of the present invention is shown in a cross-sectional view. [Figure 4] A schematic diagram of an adjustment unit according to an embodiment of the present invention is shown in a longitudinal cross-sectional view. [Figure 5] A schematic diagram of an impact member and a spindle nut according to an embodiment of the present invention is shown in a perspective cross-sectional view. [Figure 6] A schematic diagram of an impact member and a spindle nut according to an embodiment of the present invention is shown in an exploded view. [Figure 7] A schematic diagram of an impact member and a spindle nut according to a second embodiment of the present invention is shown in a longitudinal cross-sectional view. [Figure 8] A schematic diagram of an impact member and a spindle nut according to an embodiment of the present invention is shown in a front view. [Figure 9] Enlarged schematic diagrams of details IXa and IXb in Fig. 8 are shown. [Figure 10] A schematic diagram of an adjustment unit according to an embodiment of the present invention is shown in a cross-sectional view. [Figure 11] A schematic diagram of the self-centering function of an impact member relative to a spindle nut is shown. [Figure 12] A schematic diagram of a fixing element for positioning an impact member on a spindle nut according to an embodiment of the present invention is shown. [Figure 13] A schematic diagram of a fixing element for positioning an impact member on a spindle nut according to an embodiment of the present invention is shown. [Figure 14] A schematic diagram of a fixing element for positioning an impact member on a spindle nut according to an embodiment of the present invention is shown. [Figure 15] A schematic diagram for explaining a change in the inner contour of an impact member caused by plasticization according to an embodiment of the present invention is shown. [Figure 16] A schematic diagram for explaining a change in the inner contour of an impact member caused by plasticization according to an embodiment of the present invention is shown. [Figure 17]A schematic diagram of a spindle nut according to an embodiment of the present invention is shown. [Modes for carrying out the invention]

[0029] These figures are essentially schematic diagrams and serve only to help understand the present invention. Identical elements are assigned the same reference numerals.

[0030] Figure 1 shows a schematic example of a steer-by-wire steering system 1 for a vehicle in a perspective cross-sectional view. The steer-by-wire steering system 1 includes an adjustment unit 2 (see also Figure 2) for adjusting or setting the axial length of a steering element, such as a steering wheel (not shown), and a height adjustment unit 3 for adjusting the height of the steering element. The longitudinal adjustment of the steering element is achieved, in particular, by the axial movement of a steering shaft 4 which can be coupled to the steering element to transmit torque. Furthermore, the steering system 1 has a force feedback actuator 5, which is coupled to the steering shaft 4 to transmit torque and is positioned in close proximity to the steering element on the steering shaft 4. The force feedback actuator 5 may include a motor or a motor combined with a gearbox (shown here as an example).

[0031] Adjustment unit 2 (see also Figures 2-4) comprises an adjustment unit 6 and a pull-out device 7. Adjustment unit 6 includes an adjustment motor 8, a spindle 9, and a spindle nut 10, the adjustment motor 8 being coupled to the spindle 9 to transmit torque. The spindle nut 10 is positioned on the spindle 9 such that the rotation of the spindle 9 (by the adjustment motor 8) causes axial movement of the spindle nut 10 along the spindle 9. The adjustment unit 6, in particular the adjustment motor 8, is positioned in a fixed position within the pull-out device 7.

[0032] The pull-out device 7 includes a pull-out support 11 and an inner pull-out element 12. The pull-out support 11 can be mounted to the vehicle body in a manner that is fixed in the axial direction and can pivot around a pivot axis, and the inner pull-out element 12 is positioned within the pull-out support 11 in a manner that is movable in the axial direction relative to the pull-out support 11. Furthermore, the inner pull-out element 12 is coupled to the steering shaft 4 in a manner that is fixed in the axial direction, thereby allowing the steering shaft 4 to be moved in the axial direction by the adjustment unit 6 via the inner pull-out element 12.

[0033] Furthermore, the adjustment unit 2 has an impact element 13 configured as an impact sleeve 13, which is coaxially positioned with the spindle 9 and surrounds the spindle 9 between the adjustment motor 8 and the inner draw element 12. One axial end of the sleeve 13 is positioned on the spindle nut 10 and is coupled to the spindle nut 10 in a manner that is axially fixed via at least one, in this case two, fixing elements 14 (see also Figures 5 and 6). The other axial end of the sleeve 13 is coupled to the inner draw element 12. Thus, the rotation of the spindle 9 causes axial movement of the spindle nut 10, and therefore also causes axial movement of the sleeve 13 along the spindle 10, which is coupled to the spindle nut 10 in a manner that is axially fixed, thereby causing axial movement of the inner draw element 12. In addition, the coaxial positioning of the sleeve 13 with respect to the spindle 9 allows the impact element 13 to be incorporated into the force flow of the adjustment unit 6, and therefore allows for the reduction or elimination of lateral and / or offset forces acting on the sleeve 13, especially during impact.

[0034] The fixing element 14 is configured to release the axial connection between the spindle nut 10 and the sleeve 13 when a predetermined force, particularly a predetermined impact force during a collision, is reached or exceeded, thereby allowing relative axial movement between the sleeve 13 and the spindle nut 10. Since the spindle nut 10 has a self-locking action, it can be considered stationary during a collision, thereby allowing the sleeve 13 to move axially relative to the spindle nut 10. In addition, the flat connection of the sleeve 13 to the inner drawer element 12 via both the front side of the sleeve 13 and the fastening tab allows for the symmetrical introduction of the impact force across the entire front surface of the sleeve 13 resting on the inner drawer element 12. The large support surface allows for the achievement of a high level of chipping rigidity.

[0035] As shown in Figures 8 and 9, the outer contour 15 of the spindle nut 10 and the inner contour 16 of the sleeve 13 are configured such that, in at least some parts, the outer contour 15 and the inner contour 16 overlap at least partially. More precisely, the inner contour 16 of the sleeve 13 has, here for example, a deformation region 17 located at the corner of the sleeve, which has a radius, and a buffer region 18 formed between the deformation region 17, here for example, as a straight portion of the inner contour 16 of the sleeve 13. The outer contour 15 of the spindle nut 10 and the inner contour 16 of the sleeve 13 overlap in the deformation region 17 (see the detailed view in Figure 9), where the spindle nut 10 is, for example, substantially square and has rounded corners, and the radius of the outer contour 15 of the spindle nut 10 is smaller than the radius of the inner contour 16 of the sleeve 13. In the buffer region 18, the outer contour 15 of the spindle nut 10 is positioned at a distance from the inner contour 16 of the sleeve 13.

[0036] Due to the overlap of contours 15 and 16 in the deformation region 17, the sleeve 13 is plasticized or deformed upon impact as a result of axial movement relative to the spindle nut 10 in the deformation region 17. This means that the inner contour 16 in the deformation region 17 is, so to speak, adapted to the outer contour 15 of the spindle nut 10. Any material required for this purpose comes from the buffer region 18. Thus, it can also be said that the buffer region 18 is configured to prevent tearing of the sleeve 13 due to plasticization in the deformation region 17.

[0037] As shown in Figures 7(a) and 7(b), the spindle nut 10 is particularly conical (see Figure 7(a)) and / or spherical (see Figure 7(b)) in order to prevent the sleeve 13 from tilting at the forward axial end 19 of the spindle nut 10 and / or to simplify the axial movement of the sleeve 13 relative to the spindle nut 10. This is particularly advantageous when, for any reason, the impact force (indicated here as force arrow F) is not introduced symmetrically to the impact element 13 (see Figure 10). The conical and / or spherical design of the spindle nut 10 allows for self-centering of the sleeve 13 relative to the spindle nut 10.

[0038] As shown in Figure 11, the spindle 9 "pulls" the spindle nut 10 through the sleeve 13 due to the fact that the center of gravity SP of the thread pair between the spindle 9 and the spindle nut 10 is in front of the restoring forces F1 and F2. Due to the greater restoring torque of F2 (larger lever arm z2), the spindle nut 10 aligns with the spindle 9 in the direction of the force F, thereby causing self-centering.

[0039] Figures 12 to 14 show different embodiments of the fixing element 14. In Figure 12, the fixing element 14 is configured as a shear pin 20, specifically with two pins 20 positioned on opposing surfaces. The shear pins 20 can be made of metal or plastic, and the release torque of the shear pins resulting from the impact force can be determined by both the material and diameter of the pins 20.

[0040] In Figure 13, the fixing element 14 is configured as a circumferential groove 21. The desired or required release torque can be defined by the shape and depth of the groove 21. Furthermore, it is conceivable to provide several grooves that partially extend along the circumference of the sleeve 13. The groove 21 allows the formation (formation of the groove 21), joining, and assembly of the spindle nut 10 and the sleeve 13 to be performed in a single manufacturing step, for example, by using the spindle nut 10 as a counter tool when pushing the groove 21 into the sleeve 13 for insertion. Alternatively, instead of partial grooves, it is conceivable to provide one or more "simple" recesses arranged along the circumference.

[0041] In Figure 14, the fixing element 14 is divided into two regions: on the one hand, the sleeve 13 has a tab 22 that protrudes inward at one axial end, and the tab 22 prevents independent axial movement in one axial direction. On the other hand, the spindle nut 10 is conical in at least one portion 23, which prevents independent axial displacement in the other axial direction. Additionally or alternatively, the conical portion 23 of the spindle nut 10 can function as the fixing element 14 by positive locking.

[0042] Generally, the fixing element 14 is positioned in areas of the sleeve 13 where plasticization is not performed. For example, if plasticization is performed in the corner areas of a rectangular sleeve 13 having rounded corners, the fixing element 14 is positioned in particular in the straight or flat portions between the corner areas.

[0043] Figures 15 and 16 show exemplary combinations of the inner contour 16 of the sleeve 13, the outer contour 15 of the spindle nut 10, and the inner contour 16' resulting from the plasticization of the sleeve 13 by the spindle nut 10.

[0044] In Figure 15, both the outer contour 15 of the spindle nut 10 and the inner contour 16 of the sleeve 13 are configured as rounded rectangles, and the contours overlap in the regions of the rounded corners, thereby forming a deformation region 17 (see Figure 15(a)). Figure 15(b) shows the inner contour 16' of the sleeve 13 after plasticization, where the radius of the deformation region 17 of the inner contour 16' is smaller than the radius of the inner contour 16, and the buffer region 18, i.e., the straight or flat region between the deformation regions 17 within the inner contour 16', is slightly longer than that of the inner contour 16.

[0045] In Figure 16, the sleeve 13 has, for example, a triangular inner contour 16, and the spindle nut 10 has a substantially circular outer contour 15. The outer contour 15 and the inner contour 16 do not overlap at the corners of the triangular inner contour 16, but overlap in the straight or flat portions between the corners (see Figure 16(a)). As a result, the inner contour 16' exhibits a slight "bulge" in the previously flat areas after plasticization (see Figure 16(b)).

[0046] Figure 17 shows an example embodiment of a spindle nut 10, which has a body 24 made of plastic and a sheath 25 made of sheet metal. The sheet metal of the sheath 15 is specially deep-drawn and hardened so that it can result in plasticization of the sleeve 13. The body 24 made of plastic allows for improvement of the noise behavior of the adjustment unit 6. [Explanation of symbols]

[0047] 1. Steer-by-wire steering system 2 Adjustment Unit 3. Height adjustment unit 4 (Inner) Steering Shaft 5. Force Feedback Actuator 6. Adjustment Unit 7. Drawer device 8 Adjustment Motor 9 spindles 10 Spindle nuts 11. Drawer support 12 Interior drawer elements 13 Collision Elements / Sleeves 14 fixed elements 15 Outer contour 16 Inner contour 16' Inner contour 17 Deformation Region 18 Buffer area 19 Axial end 20 shear pins 21 Groove 22 tabs 23 parts 24 Main unit 25 sheath F Impact force F1, F2 restorative force Z1, Z2 lever arm u distance SP center of gravity

Claims

1. An adjustment unit (2) for the vehicle's steering system (1), An adjustment unit (6) having an adjustment motor (8), a spindle (9), and a spindle nut (10), wherein the adjustment motor (8) is coupled to the spindle (9) to transmit torque, and the spindle nut (10) is positioned on the spindle (9) such that the rotation of the spindle (9) causes axial movement of the spindle nut (10) along the spindle (9), A drawer device (7) comprising: a drawer support (11) configured to be fixed in the axial direction and positioned on the vehicle body; and at least one inner drawer element (12) positioned within the drawer support (11) and movable in the axial direction; The inner pull-out element (12) is configured to be coupled to the steering shaft (4) in a manner that is fixed in the axial direction, and the pull-out device (7) The device has a collision element (13) which is configured as a sleeve (13) extending coaxially with the spindle (9) between the spindle nut (10) and the inner pull-out element (12), The axial end of the sleeve (13) is positioned on the spindle nut (10) and is coupled to the spindle nut (10) in such a manner that it is fixed in the axial direction via at least one fixing element (14). Adjustment unit (2), wherein the fixing element (14) is released in the event of a predetermined impact force (F), the sleeve (13) moves axially relative to the spindle nut (10), and the outer contour (15) of the spindle nut (10) and the inner contour (16) of the sleeve (13) are configured such that, in at least some portions, the sleeve (13) becomes plasticized as a result of the axial movement relative to the spindle nut (10).

2. The adjustment unit (2) according to claim 1, wherein the inner contour (16) of the non-plasticized sleeve (13) has at least partially a deformable region (17) and a buffer region (18), and the outer contour (15) of the spindle nut (10) is configured such that the outer contour (15) of the spindle nut (10) overlaps with the inner contour (16) of the sleeve (13) in the deformable region (17).

3. The adjustment unit (2) according to claim 1 or 2, wherein the spindle nut (10) has a conical or spherical outer contour (15).

4. The adjustment unit (2) according to claim 1, wherein the sleeve (13) is flatly coupled to the inner pull-out element (12) at the other axial end.

5. The adjustment unit (2) according to claim 1, wherein the sleeve (13) has a rectangular inner contour (16) with rounded corners, and the spindle nut (10) has a rectangular outer contour (15) with rounded corners, and the rounded corners of the inner contour (16) of the sleeve (13) have a larger radius than the rounded corners of the outer contour (15) of the spindle nut (10).

6. The adjustment unit (2) according to claim 1, wherein the adjustment unit (6) is located inside the drawer device (7).

7. The adjustment unit (2) according to claim 1, wherein the sleeve (13) is made of metal, particularly sheet metal.

8. The adjustment unit (2) according to claim 1, wherein the spindle nut (10) is made of a metal that is at least partially harder than the material of the sleeve (13).

9. The adjustment unit (2) according to claim 1, wherein the spindle nut (10) has a body (24) made of plastic and a sheath (25) made of metal.

10. A vehicle steering system (1), Steering shaft (4) and A steering element is coupled to the steering shaft (4) in a manner fixed in the axial direction to transmit torque, The adjustment unit (2) described in claim 1 comprises, A steering system (1) in which the steering shaft (4) is located within the drawer support (11) and is coupled to the inner drawer element (12) in a manner that is fixed in the axial direction.

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