Steering device for a motor vehicle and motor vehicle

Abstract

The invention relates to a steering device (4) for a motor vehicle (1), comprising a steering shaft (8) mechanically decoupled from the steerable wheels (7) of the motor vehicle (1), which is designed to be connected in a rotationally fixed manner to a steering wheel (3) of the motor vehicle (1), and a force feedback actuator (9) comprising an electric drive motor (13), a drive shaft (14) rotatable about a first axis of rotation (27) and driven by the drive motor (13), and a toothed belt drive (15), wherein the drive motor (13) is arranged to at least partially overlap the steering shaft (8) in a radial direction perpendicular to the longitudinal direction of the second axis of rotation (28).

Description

[0001] The invention relates to a steering device for a motor vehicle and to a motor vehicle with a steering device.

[0002] From DE 10 2020 206 359 A1, a handwheel actuator arrangement for a steer-by-wire steering system is known, wherein the handwheel actuator arrangement comprises a handwheel shaft configured to receive a handwheel, a feedback device, and a handwheel shaft position sensor. The feedback device is operable to provide a variable degree of resistance to rotation of the handwheel shaft. The handwheel shaft position sensor is operable to detect an angular position of the handwheel shaft. The handwheel shaft position sensor is mounted on a printed circuit board, the printed circuit board comprising a controller configured to receive signals from the handwheel shaft position sensor.An electric motor can be used as a feedback device, which not only allows resistance to be applied to the handwheel shaft when used to generate electric braking, but can also be used to apply force feedback.

[0003] Furthermore, DE 10 2019 101 376 A1 discloses a belt drive with a main extension axis for a feedback actuator of a steering device, comprising a torsionally rigid housing element with a torsionally rigid support wheel, a first drive belt, a drive unit rotatable about the main extension axis, a driven unit rotatable about the main extension axis, and a second drive belt. The drive unit comprises at least a first intermediate shaft having a drive intermediate shaft wheel and a driven intermediate shaft wheel. The first drive belt encloses at least the drive intermediate shaft rim and the support wheel along a first belt plane. The second drive belt encloses at least the driven intermediate shaft wheel and a driven wheel of the driven unit along a second belt plane.

[0004] Furthermore, EP 3 521 136 B1 discloses an electromechanical actuator with belt drive mechanism for a steer-by-wire handwheel actuator.

[0005] The object of the present invention is to provide a solution which enables a particularly compact arrangement of a steering device of a motor vehicle with a force feedback actuator with particularly low friction for the transmission of force from the force feedback actuator to a steering shaft of the motor vehicle in a steer-by-wire steering device.

[0006] This problem is solved according to the invention by the subject matter of the independent claims. Further possible embodiments of the invention are disclosed in the dependent claims, the description, and the figures. Features, advantages, and possible embodiments set forth in the description for one of the subject matter of the independent claims are to be regarded, at least analogously, as features, advantages, and possible embodiments of the respective subject matter of the other independent claims, as well as of any possible combination of the subject matter of the independent claims, optionally in conjunction with one or more of the dependent claims.

[0007] The invention relates to a steering device for a motor vehicle, in particular a car, especially a passenger car, comprising a steering shaft mechanically decoupled from the steerable wheels of the motor vehicle, which is configured to be rotationally fixed to a steering wheel of the motor vehicle, and a force feedback actuator. The steering shaft is configured to be rotated by a rotary movement of the steering wheel performed by the driver of the motor vehicle. The steering device is part of a steer-by-wire steering system. A steer-by-wire steering system is understood to be a system in automotive engineering in which a steering command from the steering wheel is transmitted exclusively electrically via one or more control units to an electromechanical actuator that executes the steering command. Thus, in a steer-by-wire steering system, there is no mechanical connection between the steering wheel and the steered wheels.

[0008] The force feedback actuator is designed to apply torque to the steering shaft, thereby providing the driver with a familiar steering feel in the form of hand torque, even though the steering wheel is decoupled from the electromechanical actuator executing the steering command (also known as the road wheel actuator). The controlled target value, "hand torque," should realistically reflect the current driving situation at any given time, along with providing the most accurate feedback possible regarding the road surface conditions.

[0009] The force feedback actuator comprises an electric drive unit, which can also be called an electric motor, a drive shaft that can be rotated about a first axis of rotation and is driven by the drive unit, and a toothed belt drive. The drive shaft can be formed integrally with a rotor shaft of the drive unit. In this case, the drive shaft can, for example, be designed as an axial extension of the rotor shaft.

[0010] The toothed belt drive enables a particularly low-friction and low-backlash transmission of drive torque from the drive shaft to the steering shaft. This allows for a very precise application and adjustment of the steering torque by the force-feedback actuator. The lower the friction losses and backlash of the toothed belt drive, the more precisely the steering torque can be applied to the steering shaft by the electric drive motor.If significant friction losses, particularly torque-dependent ones, occur within the force feedback actuator during the transmission of the drive torque provided by the electric motor to the steering shaft, then complex calculations may be necessary to determine the drive torque to be provided by the motor based on a predetermined manual torque setting at the steering shaft. These complex calculations are unnecessary due to the exceptionally low friction losses of the toothed belt.

[0011] The force feedback actuator comprises a toothed belt drive with at least two stages. The toothed belt drive has a first toothed belt pulley that is fixed to the steering shaft but rotatable about a second axis of rotation. A torque supplied by the electric drive motor can be transmitted to the steering shaft via at least one toothed belt. The toothed belt drive is designed to transmit and amplify torque from the drive shaft to the steering shaft. The toothed belt drive has at least one intermediate shaft to provide the at least two transmission stages. Furthermore, the toothed belt drive has a separate toothed belt for each of these transmission stages.Of these two timing belts for the two transmission stages, the first timing belt meshes with the drive shaft and the intermediate shaft, and the second timing belt meshes with the intermediate shaft and the first timing belt pulley, which is fixedly connected to the steering shaft. Thus, the drive torque provided by the drive shaft can be transmitted via the first timing belt to the intermediate shaft and from the intermediate shaft to the steering shaft via the second timing belt. The respective torque transmission ratio for the transmission of torque from the drive shaft to the intermediate shaft and from the intermediate shaft to the steering shaft can be set by the diameter ratio of the respective timing belt pulleys meshing with each other via the timing belts of the drive shaft and the intermediate shaft, and of the intermediate shaft and the steering shaft, respectively.The use of the toothed belt drive enables a particularly low-friction transmission of the drive torque provided by the drive motor to the steering shaft. The use of the at least two-stage toothed belt drive allows for a particularly simple and precise transmission of the drive torque provided by the drive motor to the steering shaft. Due to the two-stage transmission, the gears of the force feedback actuator, which mesh with the toothed belt, can have particularly small radial diameters, thus enabling a particularly compact force feedback actuator. Each toothed belt pulley can include at least one flange, and in particular two flanges, each located on one end face of the toothed belt pulley.The respective flange prevents the timing belt from wandering off the timing belt pulley over the respective end face on which the flange is located.

[0012] To enable a particularly compact design of the steering device, especially with regard to the axial direction parallel to the longitudinal direction of the steering shaft, the drive motor is arranged to overlap the steering shaft, at least partially, in a radial direction perpendicular to the longitudinal direction of the second axis of rotation. Specifically, the first and second axes of rotation, with their respective longitudinal directions, are arranged parallel to each other and spaced apart radially. This means that the second axis of rotation is radially spaced from the first axis of rotation. The drive motor is thus arranged to overlap the steering shaft laterally, resulting in a particularly short axial length for the steering device and thus a particularly compact design.

[0013] In a possible further development of the invention, the force feedback actuator comprises a housing in which the drive motor, the drive shaft, and the toothed belt drive are arranged together. To facilitate particularly simple transmission of torque from the first toothed belt pulley to the steering shaft, the steering shaft can be designed to project into the housing with at least one axial section. The housing allows the drive motor, the drive shaft, and the toothed belt drive to be enclosed, thus providing excellent protection for these components against contamination and damage. Furthermore, the arrangement of the drive motor, the drive shaft, and the toothed belt drive in the common housing enables a particularly compact design of the force feedback actuator, as separate housings for the drive motor, the drive shaft, and the toothed belt drive are not required.

[0014] In this context, it can be provided, in particular, that the at least one intermediate shaft, the drive shaft, and the steering shaft are mounted in the housing with their respective axes of rotation parallel to each other. In other words, the intermediate shaft, the drive shaft, and the steering shaft are aligned parallel to each other, with each of the shafts being rotatably mounted on the housing by means of at least one bearing. Mounting the respective shafts on the housing allows for particularly precise positioning of the respective shafts relative to each other.

[0015] In a further possible embodiment of the invention, the radial distance between the first axis of rotation and the second axis of rotation is smaller than the sum of the radial distances between the first axis of rotation and a third axis of rotation of the intermediate shaft, and between the second axis of rotation and the third axis of rotation. In other words, the first axis of rotation of the drive motor, the second axis of rotation of the steering shaft, and the third axis of rotation of the intermediate shaft are not all arranged side by side on a straight line extending in the radial direction. Thus, the first axis of rotation, the second axis of rotation, and the third axis of rotation do not all lie in a common plane.Instead, due to the axially parallel design, the first and second axes of rotation lie in a common first plane, the second and third axes of rotation lie in a common second plane, and the first and third axes of rotation lie together in a third plane, whereby the first, second, and third planes do not coincide but intersect each other. This allows the respective axes of rotation to be positioned very close to one another, resulting in a particularly compact force feedback actuator.

[0016] In a further possible embodiment of the invention, the first toothed belt is meshed with a toothed belt pulley on the drive shaft via helical teeth, and the second toothed belt is meshed with the first toothed belt pulley via helical teeth. In particular, the first toothed belt is meshed with the toothed belt pulley of the drive shaft and the intermediate shaft, and the second toothed belt is meshed with the intermediate shaft and the first toothed belt pulley, and via the first toothed belt pulley, with the steering shaft. Helical teeth are an arrangement of teeth on a toothed belt pulley that is not parallel to the axis of rotation. Right-hand helical teeth can be combined with left-hand helical teeth. Helical teeth enable particularly smooth running. The helical teeth thus allow for a particularly uniform transmission of torque from the drive shaft via the intermediate shaft to the steering shaft.

[0017] In a further possible embodiment of the invention, the force feedback actuator additionally comprises a steering angle sensor and / or a torque sensor. In particular, the steering angle sensor and / or the torque sensor are arranged within the housing of the force feedback actuator. The steering angle sensor and the torque sensor can form a single sensor unit. This allows the force feedback actuator comprising the steering angle sensor and / or the torque sensor to be designed in a particularly compact manner. The steering angle sensor can determine the steering angle based on the angular position of the steering shaft. A torque sensor, which can also be referred to as a torque transducer, is a sensor for detecting the physical quantity of torque. Torque indicates the force exerted on a rotatably mounted body, in this case, the steering shaft.The torque sensor measures the torque applied by the driver to the steering wheel. Based on the torque of the steering shaft and / or the steering angle, the steering command can be determined, which then determines the activation of the electromechanical actuator that executes the steering command.

[0018] In a further possible embodiment of the invention, a belt tension adjustment device is provided, which in particular comprises a wedge or an eccentric and is configured to tension at least one of the toothed belts. In a belt drive, a belt is the free, non-contacting section of the toothed belt. The belt tension force can also be referred to as belt tension or belt force and is synonymous with belt tension, belt tensile force, belt pretension force, and belt tensioning force. The belt tension force is the force that tensions the belt. The belt tension adjustment device thus makes it possible to set a predetermined tension of the respective toothed belt by adjusting the belt tension force. Tolerances of components of the force feedback actuator can therefore be particularly well compensated for by adjusting the belt tension force using the belt tension adjustment device.This ensures a reliable and particularly low-friction transmission of the drive torque provided by the drive motor to the steering shaft via the toothed belts.

[0019] The wedge or eccentric is specifically designed to set a radial distance between the drive shaft and the intermediate shaft and / or a radial distance between the intermediate shaft and the steering shaft for tensioning the respective timing belts.

[0020] In a further possible embodiment of the invention, the steering device has a mechanical end stop designed to mechanically limit the maximum rotation angle of the steering shaft. The mechanical end stop can be located, in particular, in the housing of the force feedback actuator. In an alternative embodiment, the mechanical end stop can be integrated into the steering column. This mechanical end stop can be designed as a rotation limiting device, which is configured to limit one rotation of the steering shaft. By means of the mechanical end stop, the maximum number of steering wheel rotations of the vehicle can be mechanically limited via the steering shaft.The risk of damage to vehicle components, for example components of the steering device as a result of over-rotation of the steering shaft, can be avoided particularly easily and reliably by means of the mechanical end stop.

[0021] The invention further relates to a motor vehicle with a steering device as already described in connection with the steering device according to the invention. The motor vehicle can additionally include a steering wheel which is rotationally fixed to the steering shaft. Furthermore, the motor vehicle can include a road wheel actuator as an electromechanical actuator which executes the steering command. The motor vehicle thus comprises a steer-by-wire system including the steering device.

[0022] Further features of the invention may become apparent from the following description of the figures and from the drawings. The features and combinations of features mentioned above in the description, as well as the features and combinations of features shown below in the description of the figures and / or in the figures themselves, can be used not only in the combinations specified, but also in other combinations or individually, without departing from the scope of the invention.

[0023] The drawing shows in: Fig. 1 a schematic perspective view of a section of a motor vehicle with a steer-by-wire system comprising a steering device connected to a steering wheel of the motor vehicle in a rotationally fixed manner; Fig. 2 a schematic perspective view of the steering device; Fig. 3 a schematic perspective view of a drive motor, a toothed belt drive and a drive shaft of a force feedback actuator of the steering device in a first embodiment; and Fig. 4 a schematic perspective view of a drive machine as well as a toothed belt drive and a drive shaft of a force feedback actuator of the steering device in a second embodiment different from the first embodiment.

[0024] Identical or functionally equivalent elements are marked with the same reference symbols in the figures.

[0025] In Fig. Figure 1 shows a partial schematic perspective view of a motor vehicle 1 equipped with a steer-by-wire system 2. The steer-by-wire system 2 includes a steering wheel 3, which is configured to be rotated about a pivot axis by the driver of the motor vehicle 1. The steer-by-wire system 2 also includes a steering device 4, which is connected to the steering wheel 3 to transmit torque. Furthermore, the steer-by-wire system 2 includes a road wheel actuator 5, which is configured to be controlled by an electrical signal 6 and, depending on the received electrical signal 6, to adjust the orientation of the wheels 7 of the motor vehicle 1 in order to steer the motor vehicle 1. The steering device 4 is configured to adjust the electrical signal 6 for the road wheel actuator 5 depending on a steering angle and a torque applied by the steering wheel 3.

[0026] In Fig. Figure 2 shows an enlarged perspective view of the steering device 4 and the steering wheel 3, which is non-rotatably connected to the steering device 4. The steering device 4 comprises a steering shaft 8, which can also be referred to as a profile shaft, and a force feedback actuator 9. The steering shaft 8 is connected to the steering wheel 3 via a steering column 10, transmitting torque. The force feedback actuator 9 comprises a housing 11 in which a control unit 12, an electric drive motor 13, a drive shaft 14, and a toothed belt drive 15 are arranged. Fig. Figure 2 shows the force feedback actuator 9 with a toothed belt drive 15, which is designed as a single-stage unit. However, the toothed belt drive 15 is designed as a two-stage unit in this case. The two-stage toothed belt drive 15, the drive shaft 14, and the electric drive motor 13 are shown in Figure 2. Fig. 3 and Fig. Figure 4 is shown enlarged in perspective. The housing 11 of the force feedback actuator 9 also contains a steering angle sensor 16, a torque sensor 17, and a mechanical end stop 18 for the steering shaft 8. Furthermore, in Fig. 2. A first toothed belt pulley 19, which is non-rotatably connected to the steering shaft 8, and a toothed belt 20 of the toothed belt drive 15 can be identified. Furthermore, in Fig. 2. A belt tension adjustment device 21 is identified, which is configured to set at least a radial distance between the electric drive motor 13 or the drive shaft 14 and the steering shaft 8. This belt tension adjustment device 21 may include a key and / or an eccentric. In mechanics and mechanical engineering, an eccentric is understood to be a control disc mounted on a shaft whose center point lies outside the shaft axis. The mechanical end stop 18 is configured to mechanically limit a maximum rotation angle of the steering shaft 8.

[0027] In Fig. 3 and Fig. Figure 4 shows the electric drive motor 13, the drive shaft 14, and the toothed belt drive 15 of the force feedback actuator 9 separately and enlarged. The drive torque provided by the drive motor 13 can be transmitted via the drive shaft 14 to the intermediate shaft 22 by means of toothed belts 23 and 24, and from the intermediate shaft 22 to the steering shaft 8 by means of the toothed belt drive 15. The toothed belt drive 15 comprises an intermediate shaft 22, a first toothed belt 23, and a second toothed belt 24. The drive shaft 14 and the intermediate shaft 22 are connected to each other via the first toothed belt 23 for torque transmission. The intermediate shaft 22 and the steering shaft 8 are connected to each other via the second toothed belt 24 for torque transmission. The first toothed belt 23 has helical teeth on both the drive shaft 14 and the intermediate shaft 22.The second timing belt 24 is helically toothed with both the intermediate shaft 22 and the first timing belt pulley 19. For each tooth configuration, the intermediate shaft 22 has a second timing belt pulley 25 and a third timing belt pulley 26, wherein the second timing belt pulley 25 is helically toothed with the first timing belt 23 and the third timing belt pulley 26 is helically toothed with the second timing belt 24. The second timing belt pulley 25 and the third timing belt pulley 26 have different radii. In particular, the timing belt drive 15 exhibits exceptionally low system friction. The steering shaft 8, the drive shaft 14, and the intermediate shaft 22 are each rotatably mounted on the housing 11 of the force feedback actuator 9, in particular by means of radial bearings. In this case, a fourth toothed belt wheel 30 is held non-rotatably on the drive shaft 14, which is toothed with the first toothed belt 23, in particular helical toothed.This allows the torque provided by the drive shaft 14 to be transmitted to the intermediate shaft 22 via the first toothed belt 23.

[0028] In operation, the drive shaft 14 is rotatable about a first axis of rotation 27, the steering shaft 8 is rotatable about a second axis of rotation 28, and the intermediate shaft 22 is rotatable about a third axis of rotation 29. The first axis of rotation 27, the second axis of rotation 28, and the third axis of rotation 29 are aligned parallel to each other. As shown in Fig. To ensure that the force feedback actuator 9 can be recognized particularly well, in a first embodiment it is provided that the first axis of rotation 27, the second axis of rotation 28 and the third axis of rotation 29 do not all lie in a common plane, but rather the radial distance of the first axis of rotation 27 to the second axis of rotation 28 is smaller than the sum of the radial distances of the first axis of rotation 27 to the third axis of rotation 29 and of the second axis of rotation 28 to the third axis of rotation 29. This allows the force feedback actuator 9 to be designed in a particularly compact form.

[0029] Alternatively to the one in Fig. In the embodiment shown in Figure 3, it is possible that the first axis of rotation 27, the second axis of rotation 28 and the third axis of rotation 29, as in Fig. As shown in section 4, they are arranged in a common plane.

[0030] As in the Fig. 2 and Fig.To ensure that the steering mechanism 4 can be particularly well identified, the drive motor 13 is arranged radially next to the steering shaft 8, perpendicular to the longitudinal direction of the axes of rotation and the longitudinal direction of the steering shaft 8. Thus, the drive motor 13 overlaps the steering shaft 8 radially to the side, at least in part. The steering device 4 can therefore be provided with a particularly small extent in the longitudinal direction of the steering shaft 8. Consequently, there is a particularly large degree of design freedom with regard to the arrangement of the steering device 4 within the motor vehicle 1.

[0031] When using a worm drive instead of the toothed belt drive 15, a highly variable dependence of the friction level on temperature and load conditions can occur. A noticeable improvement through purely design-related measures is not to be expected, and operation without the aid of a torque sensor to compensate for the friction is practically impossible.

[0032] Controlling the steering torque to achieve an acceptable steering feel requires a significant challenge in both steady-state and transient control of friction due to its high dynamic and non-linear nature. Friction causes a loss of information, negatively impacting and reducing the feedback generated by the steering torque, or road feedback. Therefore, to provide the driver with authentic, high-frequency road feedback via the steering wheel 3, it is crucial to minimize mechanical system friction. This prevents the reduction of frictional influences, which are not compensated for by the control system and thus inherently result in information loss. Due to the lack of tolerance for disturbances perceptible at the steering wheel 3 and the proximity of the force feedback actuator 9 to the driver, the haptic and acoustic qualities of the steering mechanism are of paramount importance.When the toothed belt drive 15 is used in the force feedback actuator 9, the friction level is significantly lower for comparable performance compared to a force feedback actuator with a worm drive. Furthermore, the toothed belt drive 15 offers considerably more systemic degrees of freedom than a worm drive.

[0033] The shafts of the toothed belt drive 15 can be mounted parallel to the axis by means of a flange or a bracket of the housing 11, and the center distances and swivel ranges of the respective shafts can be defined. The force feedback actuator 9 can be modularly coupled to the steering shaft 8. This means that the force feedback actuator 9 is designed to be coupled to different steering shafts 8, or the steering shaft 8 is designed to be coupled to force feedback actuators 9 with different configurations. Furthermore, the force feedback actuator 9 can be modularly coupled to the steering column 10, in particular by means of the housing 11. The force feedback actuator 9 is also designed to be coupled to the steering shaft 8 by force-fit and / or positive-fit. It can be provided that the drive motor 13 is modularly decoupled from the toothed belt drive 15.This means that the electric drive motor 13 is designed to be connected to different toothed belt drives 15. As an alternative to helical teeth, the first toothed belt 23 can have spur teeth with the drive shaft 14 and / or the intermediate shaft 22, and / or the second toothed belt 24 can have spur teeth with the intermediate shaft 22 and / or the steering shaft 8. The housing 11 is specifically designed to ensure a degree of protection for the force feedback actuator 9 according to the IP code. Furthermore, the belt tension adjustment device 21 may include a structural element for adjusting the belt tension of at least one of the toothed belts 23, 24.In comparison to the use of a force feedback actuator 9 with a worm drive, the design of the force feedback actuator 9 with the toothed belt drive 15 enables lower system friction and, if necessary, the elimination of the torque sensor 17, an increase in the systemic degrees of freedom, which are relevant to installation space, a reduction in costs through the reduction of components, complexity and process steps, as well as a simple implementation of alternative transmission ratios by decoupling the drive machine 13 from the toothed belt drive 15.

[0034] Overall, the invention shows how the force feedback actuator 9 can be implemented with a toothed belt drive - and thus with the toothed belt drive 15. Reference symbol list 1 motor vehicle 2 Steer-by-Wire system 3 Steering wheel 4 Steering device 5 Road-Wheel Actuator 6 electrical signal 7 wheel 8 Steering shaft 9 Force feedback actuator 10 Steering column 11 cases 12 Control unit 13 electric drive motor 14 Drive shaft 15 Timing belt transmission 16 Steering angle sensor 17 Torque sensor 18 mechanical end stop 19 first toothed belt pulley 20 timing belts 21 Belt pulley force adjustment device 22 Intermediate shaft 23 first timing belt 24 second timing belt 25 second timing belt pulley* 26 third toothed belt pulley* 27 first axis of rotation 28 second axis of rotation 29 third axis of rotation 30 fourth toothed belt pulley QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] DE 10 2020 206 359 A1

[0002] DE 10 2019 101 376 A1

[0003] EP 3 521 136 B1

[0004]

Claims

[1] Steering device (4) for a motor vehicle (1), comprising a steering shaft (8) mechanically decoupled from the steerable wheels (7) of the motor vehicle (1), which is designed to be connected in a rotationally fixed manner to a steering wheel (3) of the motor vehicle (1), and comprising a force feedback actuator (9), which - an electric drive motor (13), - a drive shaft (14) that can be driven by the drive machine (13) and is rotatable about a first axis of rotation (27), and - a toothed belt drive (15) comprising a first toothed belt pulley (19) rotatably connected to the steering shaft (8) about a second axis of rotation (28), wherein the toothed belt drive (15) is configured to transmit and thereby multiply a torque from the drive shaft (14) via the first toothed belt pulley (19) to the steering shaft (8), wherein, for the provision of at least two transmission stages, the toothed belt drive (15) has at least one intermediate shaft (22) and, for each transmission stage, a respective toothed belt (20, 23, 24), of which a first toothed belt (23) is toothed with the drive shaft (14) and the second toothed belt (24) is toothed with the first toothed belt pulley (19), wherein, in a radial direction perpendicular to the longitudinal direction of the second axis of rotation (28), the drive machine (13) is arranged to cover the steering shaft (8) at least partially. [2] Steering device (4) according to claim 1, wherein the force feedback actuator (9) has a housing (11) in which the drive motor (13), the drive shaft (14) and the toothed belt drive (15) are arranged together. [3] Steering device (4) according to claim 2, wherein the at least one intermediate shaft (22), the drive shaft (14) and the steering shaft (8) are mounted on the housing (11) with their respective axes of rotation (27, 28, 29) parallel to each other. [4] Steering device (4) according to one of the preceding claims, wherein the radial distance of the first axis of rotation (27) to the second axis of rotation (28) is smaller than the sum of the radial distances of the first axis of rotation (27) to a third axis of rotation (29) of the intermediate shaft (22) and of the second axis of rotation (28) to the third axis of rotation (29). [5] Steering device (4) according to one of the preceding claims, wherein the first toothed belt (23) is toothed via helical teeth with a toothed belt wheel (30) of the drive shaft (14) and the second toothed belt (24) is toothed via helical teeth with the first toothed belt wheel (19). [6] Steering device (4) according to one of the preceding claims, wherein the force feedback actuator (9) additionally comprises a steering angle sensor (16) and / or a torque sensor (17). [7] Steering device (4) according to one of the preceding claims, wherein a belt tension adjustment device (21) is provided, which in particular comprises a wedge or an eccentric and is configured to tension at least one of the toothed belts (20, 23, 24). [8] Steering device (4) according to one of the preceding claims, wherein the steering device (4) has a mechanical end stop (18) which is configured to mechanically limit a maximum rotation angle of the steering shaft (8). [9] Motor vehicle (1) with a steering device (4) according to one of the preceding claims.

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