Device for limiting steering wheel rotation

Abstract

The invention relates to a device (1) for limiting steering wheel rotation, comprising: an immovable end stop (4); a stop sleeve (5) on a steering shaft (2), the stop sleeve being immovable relative to the steering shaft; a sleeve stop (6) on the stop sleeve (5); a guide ring unit (7) on the steering shaft (2), the guide ring unit having a guide ring (8); and a guide ring stop (9) on the guide ring (8). According to the invention, the guide ring unit (7) comprises an axial bearing ring (10), which is rotationally rigidly arranged on the guide ring (8) and has a soft component (12) forming an axial bearing ring stop (13) which covers and projects beyond the guide ring stop (9) in the direction of rotation, the guide ring unit (7) is rotationally rigidly connected to the steering shaft (2) by means of a wave spring (18), the end stop (4) and the sleeve stop (6) are spaced apart in the axial direction, the guide ring stop (9) and the sleeve stop (6) are arranged such that they overlap in the axial direction and in the radial direction and follow one another in the direction of rotation, the guide ring stop (9) and the end stop (4) are arranged such that they overlap in the axial direction and in the radial direction and follow one another in the direction of rotation, the axial bearing ring stop (13) and the end stop (4) are arranged such that they overlap in the axial direction and in the radial direction and follow one another in the direction of rotation, and, in the normal operation position, the guide ring stop (9) and the sleeve stop (6) are spaced apart from one another in the direction of rotation.

Description

[0001] 2024P00087WQ

[0002] 1

[0003] Mercedes-Benz Group AG Daniel Schönhagen

[0004] 11.07.2025

[0005] Device for limiting steering wheel rotation

[0006] The invention relates to a device for limiting a steering wheel rotation according to the features of the preamble of claim 1.

[0007] As described in DE 102021 002 436 A1, a device for limiting steering wheel rotation in a steer-by-wire steering system with a steering wheel fixed to a steering shaft rotatable about a shaft axis is known from the prior art. An actuator comprises a locking bolt movable from an open position to a closed position and vice versa. A locking ring is arranged on an outer surface of the steering shaft, which is immovable relative to the steering shaft. A circumferential toothing with several teeth and a locking ring stop are formed on an outer surface of the locking ring. The locking bolt moves into a space arranged between two adjacent teeth to lock the steering shaft and out of the space to unlock the steering shaft. A pull ring is arranged on the outer surface of the steering shaft, which is rotatable relative to the steering shaft and about the shaft axis.An end stop is immobile relative to the actuator. A driver is arranged on an outer surface of the drag ring, which, when the steering shaft is rotated, can be brought into at least indirect mechanical contact with the locking ring stop and can be rotated by means of this until the end stop is reached and abuts against the end stop.

[0008] The problem is solved according to the invention by a device for limiting a steering wheel rotation with the features of claim 1.

[0009] Advantageous embodiments of the invention are the subject of the dependent claims. 2024P00087WQ

[0010] 2

[0011] A device for limiting steering wheel rotation in a steer-by-wire steering system of a vehicle, or for a vehicle, has a steering shaft, also referred to as a steering spindle, on which a steering wheel is fixedly mounted. The steering shaft is rotatably mounted about a shaft axis in a sleeve tube.

[0012] An end stop that is fixed relative to the outer tube is provided. For example, the end stop is designed as a cam plate attached to the outer tube.

[0013] A stop sleeve is arranged on an outer surface of the steering shaft, which is immovable relative to the steering shaft. A sleeve stop is formed on an outer surface of the stop sleeve.

[0014] A guide ring unit with a guide ring is arranged on the outer surface of the steering shaft. A guide ring stop is formed on an outer surface of the guide ring.

[0015] According to the invention, the guide ring unit has an axial bearing ring which is arranged on an end face of the guide ring, is rotationally fixed to the guide ring and has an annular hard component and a soft component which forms an axial bearing ring stop, wherein the axial bearing ring stop covers the guide ring stop in the direction of rotation and a respective stop end of the axial bearing ring stop projects beyond a respective stop end of the guide ring stop in the direction of rotation.

[0016] The hard component and the soft component are each made of a different plastic, for example, with the plastic of the hard component being harder than the plastic of the soft component. For example, the soft component is made of an elastomer.

[0017] For example, the guide ring has an annular centering projection on the end face where the axial bearing ring is arranged, for receiving the axial bearing ring on which the axial bearing ring is mounted. An inner diameter of the axial bearing ring advantageously corresponds, at least substantially, to an outer diameter of the centering projection. It is further advantageous if the 2024P00087WQ

[0018] 3

[0019] The guide ring, the centering element, and the axial bearing ring are manufactured as a single piece using a suitable manufacturing process, such as injection molding. Such a single-piece design is easier and faster to assemble than a multi-part design.

[0020] The guide ring assembly is rotationally fixed to the steering shaft by means of a spring force of a spring element, in particular designed as a wave spring, wherein the steering shaft can be rotated about the shaft axis relative to the guide ring assembly by overcoming the spring force of the spring element, in particular designed as a wave spring. For example, the steering shaft is rotatably mounted about the shaft axis in the outer tube by means of a rolling bearing, in particular a ball bearing, wherein the spring element, in particular designed as a wave spring, is arranged in the axial direction between an inner bearing ring of the rolling bearing, which is fixedly connected to the steering shaft, on the one hand, and the axial bearing ring and / or the guide ring of the guide ring assembly on the other hand, and is in particular pre-tensioned.The guide ring unit, in particular the guide ring, in particular an end face of the guide ring unit, in particular of the guide ring, facing away from the spring element, in particular designed as a wave spring, rests against the stop sleeve, in particular in the axial direction, so that no axial displacement of the guide ring unit is possible.

[0021] The end stop and the sleeve stop of the stop sleeve are arranged axially spaced apart from each other. This allows the sleeve stop to pivot past the end stop during a rotational movement of the steering wheel and thus the steering shaft in the direction of rotation, without touching the end stop.

[0022] The guide ring stop of the guide ring and the sleeve stop of the stop sleeve are arranged to overlap axially in sections, to overlap at least partially or completely radially, and to follow one another in the direction of rotation. Depending on the relative position of the guide ring and the stop sleeve in the direction of rotation, the sleeve stop of the stop sleeve is either spaced apart from the guide ring stop of the guide ring or abuts it in the direction of rotation.

[0023] The guide ring stop of the guide ring is arranged to overlap the end stop in the axial and radial directions, with the end stop and the guide ring stop of the guide ring being successive in the direction of rotation. 2024P00087WQ

[0024] 4 are arranged. Depending on the rotational position of the steering wheel and thus of the steering shaft, and depending on the relative position of the guide ring unit in the direction of rotation to the steering shaft, the guide ring stop of the guide ring is spaced away from the end stop or is in contact with it in the direction of rotation.

[0025] The axial bearing ring stop of the axial bearing ring is arranged to overlap the end stop at least partially in both the axial and radial directions, with the end stop and the axial bearing ring stop of the axial bearing ring being arranged consecutively in the direction of rotation. Depending on the rotational position of the steering wheel and thus the steering shaft, and depending on the relative position of the guide ring unit in the direction of rotation to the steering shaft, the axial bearing ring stop of the axial bearing ring is either spaced from the end stop or abuts it in the direction of rotation.

[0026] The guide ring stop of the guide ring and the sleeve stop of the stop sleeve are spaced apart from each other in the direction of rotation in a normal operating position.

[0027] The directional specifications, in particular axial direction, radial direction and direction of rotation, refer specifically to the steering shaft and / or to the shaft axis about which the steering shaft can rotate.

[0028] It is specifically provided that, in the axial direction, the stop sleeve, the guide ring, the axial bearing ring, the spring element (in particular designed as a wave spring), the rolling bearing, and the steering wheel are arranged in the aforementioned order, wherein at least the stop sleeve, the guide ring, the axial bearing ring, the spring element (in particular designed as a wave spring), and the rolling bearing are arranged directly one after the other. Further components may, for example, be arranged between the rolling bearing and the steering wheel. In particular, the guide ring unit, and especially its guide ring, rests axially against the stop sleeve, so that the spring element (in particular designed as a wave spring) is preloaded between the inner bearing ring of the rolling bearing on the one hand and the axial bearing ring and / or the guide ring of the guide ring unit on the other.

[0029] The described solution enables quiet limitation of the steering wheel rotation during normal operation of the steer-by-wire steering system and simultaneously high load capacity in a misuse case, i.e., outside of normal operation, 2024P00087WQ

[0030] 5. This is especially true when the steering wheel is turned too sharply, i.e., when the steering wheel angle is too large. The described solution is robust, cost-effective, and compact.

[0031] Limiting the steering wheel rotation is necessary in steer-by-wire systems because there is no mechanical fallback mechanism, which can lead to the steering wheel turning freely in certain situations. A mechanical steering stop, which is often implemented in the steering gear of conventional steering systems, is also either absent or ineffective in steer-by-wire systems.

[0032] In the described solution, the steering wheel rotation is limited to a maximum of + / - 200°, for example.Upon reaching this limit, in the direction of rotation, one side of the guide ring stop of the guide ring rests against one side of the end stop, and one side of the sleeve stop of the stop sleeve rests against the other side of the guide ring stop of the guide ring. This occurs because, due to steering forces acting on the steering wheel, the spring force of the spring element, which is designed in particular as a wave spring, has been overcome, and the steering shaft, and thus also the stop sleeve, has been rotated relative to the guide ring unit until the sleeve stop of the stop sleeve abuts the guide ring stop of the guide ring. A stop end of the axial bearing ring stop also rests against the end stop, whereby this stop end of the axial bearing ring stop, designed as a soft component, has already deformed, in particular elastically deformed, due to the steering forces acting on the steering wheel to rotate the steering wheel to this steering wheel angle.has given way, so that the guide ring stop of the guide ring has come into contact with the end stop.

[0033] The contact ends of the axial bearing ring stop are designed in such a way that they are pressed over without damage in such a case of misuse, and torque transmission then takes place directly between the guide ring, in particular its guide ring stop, and the end stop, which is designed in particular as a cam plate.

[0034] Under normal operating conditions, the steering wheel rotation is limited to + / - 180° by an actuator. However, if this soft stop is overridden, the steering wheel angle must be mechanically limited. The noise generated at the end stop by the contact of the guide ring and stop sleeve is acceptable, as it only occurs in a misuse case (2024P00087WQ).

[0035] 6 occurs, i.e., only in the described case of an excessively large steering wheel angle. The contact between the guide ring and the stop sleeve therefore does not need to be damped, because in normal operation the guide ring is rotationally fixed to the steering shaft by means of the spring force of the spring element, which is designed in particular as a wave spring, so that both the guide ring and the stop sleeve rotate together with the steering shaft and therefore do not strike each other.

[0036] In normal operation, only the end of the axial bearing ring stop, which projects beyond the guide ring stop in the direction of rotation, strikes the end stop at a sufficiently large steering wheel angle. This impact and any associated noise are dampened due to the design of the axial bearing ring stop as a soft component. The projection of the axial bearing ring stop's ends beyond the guide ring stop in the direction of rotation is specifically designed to prevent direct contact between the guide ring, particularly its guide ring stop, and the end stop, which is designed as a cam plate, even during rapid steering movements.

[0037] Exemplary embodiments of the invention are explained in more detail below with reference to drawings.

[0038] This shows:

[0039] Fig. 1 schematically shows a longitudinal section of a device for limiting steering wheel rotation in a steer-by-wire steering system, Fig. 2 schematically shows a side view of the device without the outer tube, Fig. 3 schematically shows a longitudinal section of the device without the outer tube, Fig. 4 schematically shows a top view of a front face of an axial bearing ring of the device facing a steering wheel.

[0040] Fig. 5 schematically shows a side view of the axial bearing ring,

[0041] Fig. 6 schematically shows a top view of the back side of an axial bearing ring,

[0042] Fig. 7 schematically shows a top view of a rear side facing away from the steering wheel of a guide ring unit having the axial bearing ring,

[0043] Fig. 8 schematically shows a side view of the guide ring unit, Fig. 9 schematically shows another side view of the guide ring unit,

[0044] Fig. 10 schematically shows another side view of the axial bearing ring, 2024P00087WQ

[0045] 7

[0046] Fig. 11 schematically shows a side view of a guide ring of the guide ring unit,

[0047] Fig. 12 schematically shows a perspective view of the device without the outer tube in a starting position with respect to a steering wheel angle; Fig. 13 schematically shows the device without the outer tube in the starting position with respect to the steering wheel angle in a top view from the front, i.e. from the direction of a steering wheel (not shown).

[0048] Fig. 14 schematically shows the device without a casing tube with a steering wheel rotated 95° in one direction of rotation from the initial position, in a top view from the front.

[0049] Fig. 15 schematically shows the device without the outer tube with the steering wheel rotated a further 85° in this direction of rotation in a top view from the front, and Fig. 16 schematically shows the device without the outer tube with the steering wheel rotated a further 20° in this direction of rotation in a top view from the front.

[0050] Corresponding parts are marked with the same reference symbols in all figures.

[0051] With reference to Figures 1 to 16, an exemplary embodiment of a device 1 for limiting a steering wheel rotation in a steer-by-wire steering system is described below.

[0052] The device 1 has a steering shaft 2 on which a steering wheel (not shown) is fixedly arranged. The steering shaft 2 is rotatably mounted about a shaft axis A in a casing tube 3.

[0053] An end stop 4, which is fixed relative to the outer tube 3, is provided. In the illustrated example, the end stop 4 is designed as a cam plate that is attached to the outer tube s, in particular screwed to it, as shown in Figure 1. For the sake of clarity, Figures 2 and 3, as well as 12 to 16, show the device 1 and thus also the end stop 4 designed as a cam plate without the outer tube 3. 2024P00087WQ

[0054] 8

[0055] A stop sleeve 5 is arranged on an outer surface of the steering shaft 2, which is immovable relative to the steering shaft 2. A sleeve stop 6 is formed on an outer surface of the stop sleeve 5.

[0056] A guide ring unit 7 with a guide ring 8 is arranged on the outer surface of the steering shaft 2. A guide ring stop 9 is formed on an outer surface of the guide ring 8.

[0057] The guide ring unit 7 has a thrust bearing ring 10, which is arranged on an end face of the guide ring 8, is rotationally fixed to the guide ring 8, and has an annular hard component 11 and a soft component 12, which form a thrust bearing ring stop 13. The thrust bearing ring stop 13 overlaps the guide ring stop 9 in the direction of rotation, with each stop end 14 of the thrust bearing ring stop 13 projecting beyond each stop end of the guide ring stop 9 in the direction of rotation.

[0058] Figures 4 to 6 and 10 show the axial bearing ring 10 of the guide ring assembly 7 in different views. Figure 11 shows the guide ring 8 in a side view, and Figures 7 to 9 show the guide ring assembly 7 with the guide ring 8 and the axial bearing ring 10 arranged thereon. In Figures 5 and 10, a torque support feature 15 can be seen, which is formed on the axial bearing ring 10, in particular on its hard component 11. With this torque support feature 15, the axial bearing ring 10 engages in a corresponding recess 16 formed in the guide ring 8, as shown in Figure 8. In this way, the axial bearing ring 10 is connected to the guide ring 8 in a rotationally fixed manner.

[0059] In the illustrated example, the guide ring 8 has an annular centering projection 17 on its end face, where the axial bearing ring 10 is arranged, for receiving the axial bearing ring 10, on which the axial bearing ring 10 is arranged. This centering projection 17 on the guide ring 8 is shown in Figure 11.

[0060] The guide ring unit 7 is rotationally fixed to the steering shaft 2 by means of a spring force of a spring element designed as a wave spring 18, wherein the steering shaft 2 is 2024P00087WQ

[0061] 9. Overcoming the spring force of the wave spring 18 relative to the guide ring unit 7 allows the steering shaft 2 to rotate about the shaft axis A. In the illustrated example, the steering shaft 2 is rotatably mounted about the shaft axis A in the outer tube 3 by means of a rolling bearing 19, in particular a ball bearing, as shown in Figures 1 to 3. In the illustrated example, the wave spring 18 is arranged axially between an inner bearing ring 20 of the rolling bearing 19, which is fixedly connected to the steering shaft 2, on the one hand, and the axial bearing ring 10 and / or the guide ring 8 of the guide ring unit 7 on the other hand, in particular pre-tensioned, as shown in Figures 2 and 3. The guide ring unit 7, in particular the guide ring 8, in particular an end face of the guide ring unit 7 facing away from the wave spring 18, bears against the stop sleeve 5, in particular in the axial direction, so that no axial displacement of the guide ring unit 7 is possible.

[0062] The end stop 4, designed as a cam plate, and the sleeve stop 6 of the stop sleeve 5 are arranged axially spaced apart from each other, as can be seen particularly in Figures 1 to 3. This allows the sleeve stop 6 to pivot past the end stop 4 during a rotational movement of the steering wheel and thus of the steering shaft 2 in the direction of rotation, without touching the end stop 4.

[0063] The guide ring stop 9 of the guide ring 8 and the sleeve stop 6 of the stop sleeve 5 are arranged to overlap axially in sections, to overlap at least in sections or completely radially, and to follow one another in the direction of rotation. Depending on the relative position of the guide ring 8 and the stop sleeve 5 in the direction of rotation, the sleeve stop 6 of the stop sleeve 5 is either spaced apart from the guide ring stop 9 of the guide ring 8 or is in contact with it in the direction of rotation.

[0064] The guide ring stop 9 of the guide ring 8 is arranged to overlap the end stop 4, which is designed as a cam plate, in both the axial and radial directions, with the end stop 4 and the guide ring stop 9 of the guide ring 8 being arranged successively in the direction of rotation. Depending on the rotational position of the steering wheel and thus of the steering shaft 2, and depending on the relative position of the guide ring unit 7 in the direction of rotation to the steering shaft 2, the guide ring stop 9 2024P00087WQ

[0065] 10 of the guide ring 8 is spaced away from the end stop 4 or lies against it in the direction of rotation.

[0066] The axial bearing ring stop 13 of the axial bearing ring 10 is arranged to overlap the end stop 4, which is designed as a cam plate, at least partially in both the axial and radial directions, with the end stop 4 and the axial bearing ring stop 13 of the axial bearing ring 10 being arranged consecutively in the direction of rotation. Depending on the rotational position of the steering wheel and thus of the steering shaft 2, and depending on the relative position of the guide ring unit 7 in the direction of rotation to the steering shaft 2, the axial bearing ring stop 13 of the axial bearing ring 10 is either spaced apart from the end stop 4 or abuts it in the direction of rotation.

[0067] The guide ring stop 9 of the guide ring 8 and the sleeve stop 6 of the stop sleeve 5 are spaced apart from each other in the direction of rotation in a normal operating position.

[0068] The directional specifications, in particular axial direction, radial direction and direction of rotation, refer in particular to the steering shaft 2 and / or to the shaft axis A about which the steering shaft 2 is rotatable.

[0069] In the illustrated example, the stop sleeve 5, the guide ring 8, the axial bearing ring 10, the wave spring 18, the rolling bearing 19 (designed as a ball bearing), and the steering wheel are arranged in the specified order in the axial direction, with at least the stop sleeve 5, the guide ring 8, the axial bearing ring 10, the wave spring 18, and the rolling bearing 19 being arranged directly one after the other. Further components may, for example, be arranged between the rolling bearing 19 and the steering wheel. In particular, the guide ring unit 7, and especially its guide ring 8, rests axially against the stop sleeve 5, so that the wave spring 18 is preloaded between the inner bearing ring 20 of the rolling bearing 19 on the one hand and the axial bearing ring 10 and / or the guide ring 8 of the guide ring unit 7 on the other.

[0070] The described solution enables quiet limitation of the steering wheel rotation during normal operation of the steer-by-wire steering system and simultaneously high load capacity in a misuse case, i.e. outside of normal operation, in particular 2024P00087WQ

[0071] 11. This occurs when the steering wheel is turned too sharply, i.e., when the steering wheel angle is too large. The described solution is robust, cost-effective, and compact.

[0072] In the described solution, the steering wheel rotation is limited to a maximum of + / - 200°, as shown in the exemplary sequence of a steering wheel rotation according to Figures 12 to 16. There, the steering wheel, and thus the steering shaft 2, is rotated in one direction. The same sequence occurs when the steering wheel, and thus the steering shaft 2, is rotated in the other direction.

[0073] Upon reaching this limit, in the direction of rotation, one side of the guide ring stop 9 of the guide ring 8 rests against one side of the end stop 4, which is designed as a cam plate; one side of the sleeve stop 6 of the stop sleeve 5 rests against the other side of the guide ring stop 9 of the guide ring 8, since the spring force of the wave spring 18 has been overcome due to steering forces acting on the steering wheel, and the steering shaft 2, and thus also the stop sleeve 5, has been rotated relative to the guide ring unit 7 until the sleeve stop 6 of the stop sleeve 5 is abutted against the guide ring stop 9 of the guide ring 8; and a stop end 14 of the axial bearing ring stop 13 also rests against the end stop 4, which is designed as a cam plate, whereby this stop end 14 of the axial bearing ring stop 13, which is designed as a soft component 12, has already been deformed due to the steering forces acting on the steering wheel in order to turn the steering wheel to this steering wheel angle.in particular, it has deformed elastically, i.e., it has yielded, so that the guide ring stop 9 of the guide ring 8 has come into contact with the end stop 4. This is shown in Figure 16.

[0074] The stop ends 14 of the axial bearing ring stop 13 are designed in such a way that they are pressed over without damage in such a case of misuse and a torque transmission then takes place directly between the guide ring 8, in particular its guide ring stop 9, and the end stop 4, which is designed in particular as a cam plate.

[0075] Under normal operating conditions, the steering wheel rotation is limited to + / - 180° by an actuator. However, if this soft stop is overridden, the steering wheel angle must be mechanically limited. The noise caused by the contact between guide ring 8 and stop sleeve 5 is acceptable, as it only occurs with a 2024P00087WQ

[0076] The misuse case 12 occurs, i.e., only in the described case of an excessively large steering wheel angle, as shown in Figure 16. The contact between the guide ring 8 and the stop sleeve 5 therefore does not need to be damped, because in normal operation the guide ring 8 is rotationally fixed to the steering shaft 2 by means of the spring force of the wave spring 18, so that both the guide ring 8 and the stop sleeve 5 rotate together with the steering shaft 2 and therefore do not strike each other, as can be seen in Figures 12 to 14.

[0077] In normal operation, only one end 14 of the axial bearing ring stop 13, which projects beyond the guide ring stop 9 of the guide ring 8 in the direction of rotation, strikes the end stop 4, designed as a cam plate, at a sufficiently large steering wheel angle, as shown in Figure 14. This impact and the corresponding impact noise are dampened due to the design of the axial bearing ring stop 13 as a soft component 12. The projection of the ends 14 of the axial bearing ring stop 13 in the direction of rotation beyond the guide ring stop 9 is specifically designed such that even during rapid steering movements, no direct contact occurs between the guide ring 8, particularly its guide ring stop 9, and the end stop 4, which is designed as a cam plate.

[0078] Figures 12 and 13 show an assumed initial position of the device 1 with respect to a steering wheel angle, in particular with a steering wheel angle of 0°, corresponding to straight-ahead driving of a vehicle which has the steer-by-wire steering system with the device 1.

[0079] Figure 14 shows the device 1 with the steering wheel rotated from its initial position by a steering wheel angle value X1 of 95° in one direction of rotation. Until contact is made between the stop end 14 of the axial bearing ring stop 13 of the axial bearing ring 10 of the guide ring unit 7 and the end stop 4, which is designed as a cam plate, all components connected to the steering shaft 2 in this state, i.e., in particular the stop sleeve 5, the guide ring unit 7, the wave spring 18 and the inner bearing ring 20 of the rolling bearing 19, move together, i.e., they rotate together with the steering shaft 2, because the

[0080] The assembly consists of the inner bearing ring 20 of the rolling bearing 19, wave spring 18, and guide ring unit 7, which is axially preloaded by means of the wave spring 18. 2024P00087WQ

[0081] 13

[0082] Figure 15 shows the device 1 with the steering wheel rotated by a steering angle X2 of a further 85° in this direction of rotation. If the rotational movement of the steering shaft 2 is continued in this way, the further rotational movement of the guide ring unit 7 is stopped, since the stop end 14 of the axial bearing ring stop 13 of the axial bearing ring 10 of the guide ring unit 7 is already in contact with the end stop 4, which is designed as a cam plate. The axial bearing ring 10, in particular its axial bearing ring stop 13, designed as a soft component 12, and especially its stop end 14, serves to stop the rotational movement of the guide ring unit 7 without noise. The steering shaft 2 is now rotated further by overcoming the spring force of the wave spring 18, whereby the stop sleeve 5, which remains rotationally fixed to the steering shaft 2, continues to rotate together with the steering shaft 2 and thus rotates relative to the no longer rotating guide ring unit 7.This causes the sleeve stop 6 of the stop sleeve 5 to approach the guide ring stop 9 of the guide ring 8 in the direction of rotation.

[0083] Figure 16 shows the device 1 with the steering wheel rotated by a steering angle value X3 of a further 20° in this direction of rotation. The steering shaft 2 was rotated further, overcoming the spring force of the wave spring 18, until the stop sleeve 5, which remains rotationally fixed to the steering shaft 2, rotated together with the steering shaft 2 to such an extent—that is, it rotated relative to the no longer rotating guide ring unit 7—that the sleeve stop 6 of the stop sleeve 5 abutted the guide ring stop 9 of the guide ring 8 in the direction of rotation. After this mechanical end stop was reached and a higher torque was applied to the steering wheel, the stop end 14 of the axial bearing ring stop 13, designed as a soft component 12, was pressed over.Force is now transmitted via the steering shaft 2, the stop sleeve 5 with its sleeve stop 6, the guide ring 8 with its guide ring stop 9, and the end stop 4, which is designed as a cam plate. In this way, a high torque can be supported, particularly on the outer tube s, to which the end stop 4, designed as a cam plate, is attached. In this case, noise is permissible, as this situation only occurs in a misuse scenario.

Claims

2024P00087WQ 14 Mercedes-Benz Group AG Daniel Schönhagen 11.07.2025 Patent claims 1. Device (1) for limiting a steering wheel rotation in a steer-by-wire steering system with a steering wheel arranged rotatably on a steering shaft (2), wherein - the steering shaft (2) is rotatably mounted in a casing tube (3) about a shaft axis (A), - an end stop (4) that is immovable relative to the outer tube (3) is provided, - a stop sleeve (5) is arranged on an outer steering shaft surface of the steering shaft (2), which is immovable relative to the steering shaft (2), - a sleeve stop (6) is formed on an outer stop sleeve surface of the stop sleeve (5), - a guide ring unit (7) with a guide ring (8) is arranged on the outer steering shaft surface of the steering shaft (2), and - a guide ring stop (9) is formed on an outer guide ring surface of the guide ring (8), characterized in that - the guide ring unit (7) has an axial bearing ring (10) which is arranged on an end face of the guide ring (8), is rotationally fixed to the guide ring (8) and has an annular hard component (11) and a soft component (12) which forms an axial bearing ring stop (13), wherein the axial bearing ring stop (13) covers the guide ring stop (9) in the direction of rotation and a respective stop end (14) of the axial bearing ring stop (13) projects beyond a respective stop end of the guide ring stop (9) in the direction of rotation, - the guide ring unit (7) is rotationally fixed by means of a spring force of a wave spring (18) 2024P00087WQ 15 is connected to the steering shaft (2) and is rotatable about the shaft axis (A) relative to the guide ring unit (7) by overcoming the spring force of the wave spring (18), - the end stop (4) and the sleeve stop (6) of the stop sleeve (5) are arranged axially spaced apart from each other, - the guide ring stop (9) of the guide ring (8) and the sleeve stop (6) of the stop sleeve (5) are arranged overlapping section by section in the axial direction, overlapping at least section by section in the radial direction and following each other in the direction of rotation, - the guide ring stop (9) of the guide ring (8) is arranged to overlap the end stop (4) in the axial and radial directions, wherein the end stop (4) and the guide ring stop (9) of the guide ring (8) are arranged successively in the direction of rotation, - the axial bearing ring stop (13) of the axial bearing ring (10) is arranged to overlap the end stop (4) at least partially in the axial direction and in the radial direction, wherein the end stop (4) and the axial bearing ring stop (13) of the axial bearing ring (10) are arranged successively in the direction of rotation, and - the guide ring stop (9) of the guide ring (8) and the sleeve stop (6) of the stop sleeve (5) are spaced apart from each other in a normal operating position in the direction of rotation.

2. Device (1) according to claim 1 , characterized in that the steering shaft (2) is rotatably mounted in the casing tube (3) by means of a rolling bearing (19) about the shaft axis (A), wherein the wave spring (18) is arranged in the axial direction between an inner bearing ring (20) of the rolling bearing (19) which is fixedly connected to the steering shaft (2) on the one hand and the axial bearing ring (10) and / or the guide ring (8) of the guide ring unit (7) on the other hand.

3. Device (1) according to claim 2, characterized in that the rolling bearing (19) is designed as a ball bearing.

4. Device (1) according to one of the preceding claims, characterized in that the end stop (4) is designed as a cam plate attached to the casing tube (3).

5. Device (1) according to one of the preceding claims, characterized in that the hard component (11) and the soft component (12) of the axial bearing ring (10) are each made of a plastic, wherein the plastic of the hard component (11) is harder than the plastic of the soft component (12).

6. Device (1) according to one of the preceding claims, characterized in that the soft component (12) of the axial bearing ring (10) is made of an elastomer.

7. Device (1) according to one of the preceding claims, characterized in that the guide ring (8) has an annular centering feature (17) on the end face on which the axial bearing ring (10) is arranged for receiving the axial bearing ring (10).

8. Device (1) according to claim 7, characterized in that an inner diameter of the axial bearing ring (10) corresponds to an outer diameter of the centering feature (17).

9. Device (1) according to claim 8, characterized in that the guide ring (8), the centering form (17) and the axial bearing ring (10) are designed as a single-piece workpiece.

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