Sensor apparatus for determining a steering angle of a steering device for a motor vehicle, and steering gear and motor vehicle

Abstract

The invention relates to a sensor apparatus (1) for reliably and accurately determining a steering angle of a steering gear (2) for a motor vehicle (3), characterized by a sensor device (4) having a rotor (9) for determining an angle of rotation, and an Oldham coupling (5) having a first interface (6) for play-free connection to a predefined first shaft (7) of the steering gear, which first shaft is coupled in terms of movement to a predefined steering shaft of the steering gear (2), and a second interface (8) which is fixedly connected to the rotor (9) of the sensor device (4). The invention further relates to an associated steering gear (21) and to an associated motor vehicle (3).

Description

[0001] Sensor device for determining a steering angle of a steering device for a motor vehicle, as well as steering gear and motor vehicle

[0002] The invention relates to a sensor device for determining a steering angle of a steering device for a motor vehicle, as well as an associated steering gear with a steering shaft, and an associated motor vehicle.

[0003] Steering gears for motor vehicles are known. The steering gear can be part of the steering system of a motor vehicle and convert the rotary movement of the steering wheel or an electromechanical actuator into a sliding movement of the steering gear's tie rods, allowing the vehicle's tires to be steered. The steering gear can have a steering shaft, which, in a mechanical steering system, can be connected to a steering axle, which in turn is mechanically connected to the steering wheel. By rotating the steering shaft, which can be mechanically connected to the tie rods, a steering angle of the steering gear or the tires can be adjusted, in particular in a directly proportional manner.

[0004] Particularly in so-called steer-by-wire steering gears, the steering angle can be adjusted by an electromechanical actuator based on control signals. A mechanical coupling of the steering shaft to the steering axle or steering wheel may therefore no longer be necessary. However, it may be necessary to determine the set steering angle of the steering gear in order to steer the vehicle. For example, the steering angle can be determined via the position of the electromechanical actuator. However, the force or torque transmission of the electromechanical actuator to components of the steering gear may be subject to slippage, making this type of determination of the steering angle prone to errors.

[0005] The invention is based on the object of providing a sensor device, a steering gear and a motor vehicle by means of which the steering angle of the steering device can be determined reliably and accurately.

[0006] The object is achieved by the subject matter of the independent patent claims. Advantageous developments of the invention are described by the dependent patent claims, the following description, and the figures. The sensor device according to the invention is particularly suitable for steer-by-wire systems. Steer-by-wire systems do not have a mechanical connection via a steering column from the steering gear to the steering wheel, but rather, for example, only a steering column stub or stub, which is motion-coupled to the steering gear and / or the steering wheel, so that the steering column stub is rotated according to the respective steering angle of the vehicle. The sensor device according to the invention is designed to be placed on the steering column stub, so that the rotation or steering angle of the steering column can be detected at the steering wheel and / or the steering gear.From the detected steering angle, the steer-by-wire system can then, for example, drive an actuator to adjust a steering angle on the steering gear or check the actual steering angle on the steering gear.

[0007] Accordingly, a steering device according to this invention is a steering gear or a steering wheel device, each of which may have a steering shaft stub which is rotated proportionally to the desired or actual steering angle.

[0008] A first aspect of the invention provides a sensor device for determining a steering angle of a steering device for a motor vehicle, wherein the sensor device can be coupled to the steering device via a steering shaft stub. The sensor device has, in particular, a sensor device with a rotor which can be coupled to the steering shaft stub, wherein the sensor device is configured to determine a rotation angle, and in particular an Oldham coupling. The Oldham coupling has, in particular, a first interface for play-free connection to the first steering shaft stub of the steering device, which is motion-coupled, for example, to a predetermined push rod of a steering gear, and a second interface which is play-free connected to a rotor of the sensor device.

[0009] The steering angle of the steering gear can be determined reliably and precisely using the sensor device. The steering angle can advantageously be determined indirectly by determining the rotation angle of the first shaft. The steering angle can in particular be directly proportional to the rotation angle of the first shaft or the first steering shaft stub, so that the steering angle to be determined can be calculated directly from the determined rotation angle or directly assigned to it. For the sake of simplicity, only the first shaft, which corresponds to the first steering shaft stub, will be referred to below. The first shaft can in particular be connected to the steering shaft in a slip-free and backlash-free manner. The first shaft can in particular be mechanically connected to the steering shaft, for example via a rigid, articulated or flexible shaft coupling.The first shaft may in particular have an axial end piece, which may also be referred to as a stub, wherein the first interface may be designed for connection to the axial end piece.

[0010] The first shaft can, in particular, also be integrally connected to the steering shaft. The first shaft can, in particular, be a section of the steering shaft. Preferably, the first shaft can correspond to an axial end piece of the steering shaft, which can also be referred to as a stub of the steering shaft. The first interface can be configured accordingly for connection to the axial end piece of the steering shaft.

[0011] Since the steering shaft can be connected to the tie rods of the steering gear in a particularly slip-free manner, the steering angle of the steering gear can be determined particularly reliably by determining the angle of rotation of the first shaft, since these are directly related.

[0012] One advantage of using the Oldham coupling is that manufacturing or component tolerances can be compensated for when assembling the sensor device with the specified steering system. In particular, concentricity errors or a radial offset of the rotor to the first shaft can be compensated for. A further advantage is that the first shaft and the rotor can be coupled using the Oldham coupling, even if they are not exactly concentric with one another in an assembled state, for example due to manufacturing or component reasons. Since any concentration error is compensated for by the Oldham coupling, this has the advantage that the concentration error does not have to be compensated for by a rotor bearing with play. This means that both the rotor and the first shaft can be mounted without play.The backlash-free bearing of the rotor advantageously means that its rotation angle can be determined with particular precision. The backlash-free bearing of the rotor also advantageously means that the rotation of the rotor is not subject to any hysteresis compared to the rotation of the first shaft. The rotation of the first shaft is thus advantageously transmitted to the rotor extremely directly and simultaneously. The use of the Oldham coupling in the sensor device therefore advantageously means that component tolerances, in particular a manufacturing- or component-related radial offset of the first shaft to the rotor in an assembled state, can be compensated for, and at the same time the bearing of the rotor or the first shaft can be designed to be backlash-free in order to make the determination of the steering angle as precise as possible.A further advantage is that component tolerances can be correspondingly wide and thus production costs can be reduced, since these tolerances are compensated by the Oldham coupling.

[0013] The sensor device can be designed, in particular, to determine the steering angle of the steering device, in particular indirectly via the rotation angle of the first shaft. For example, the sensor device can be designed to determine the steering angle redundantly to a primary sensor device for determining the steering angle, which, for example, determines the steering angle directly, but may be subject to errors. Furthermore, the sensor device can also be designed, for example, solely to determine the rotation angle of the rotor or a shaft connected to the rotor.

[0014] The sensor device can be configured, in particular, to provide sensor data by means of which the rotation angle or the steering angle can be determined by a computing unit. The computing unit can also be a component of the sensor device, so that the sensor device can be configured to output data about the steering angle.

[0015] The steering gear can be part of a steering system for a motor vehicle and convert the rotary movement of the steering wheel or an electromechanical actuator into a sliding movement of the tie rods of the steering gear, so that the tires of the motor vehicle can be steered. The steering gear can have the first shaft and the steering shaft, wherein the first shaft and / or the steering shaft, in a mechanical steering system, can be connected in an assembled state in the motor vehicle to a steering axle, which in turn is mechanically connected to the steering wheel. By rotating the steering shaft, which can be mechanically connected to the tie rods, a steering angle of the steering gear or the tires can be adjusted, in particular in a directly proportional manner.

[0016] In a steer-by-wire steering system, in which steering commands are not transmitted mechanically via the steering axle, which is coupled to the steering shaft and the first shaft, but rather via electrical signals to an electromechanical actuator coupled to the steering gear, the first shaft, in particular the end piece of the first shaft, can be exposed, so that the arrangement of the sensor device on the axial end piece is advantageous. This advantage arises in particular from the fact that the first shaft continues to be used in steer-by-wire steering systems.

[0017] The steering angle can be understood in particular as the angle by which the steering device is deflected from a straight-ahead driving position. In particular, the wheel suspension of the motor vehicle or the steering gear can be deflected by the steering angle, for example by means of tie rods. In the straight-ahead driving position, the steering angle can essentially correspond to 0°; in a left-hand or right-hand driving position, the steering angle can be greater or less than 0°, for example + / - 5°, + / - 30° or + / - 60°. In particular, the steering angle can lie within a range of -90° to +90°, although larger angles are also conceivable. By means of the sensor device, the steering angle can be determined in particular to one degree, preferably to one tenth of a degree, particularly preferably to one hundredth of a degree.

[0018] The sensor device is particularly designed and configured to determine the rotation angle of the rotor. In particular, the sensor device can comprise a stator, so that a rotation angle of the rotor relative to the stator can be determined.

[0019] The sensor device is particularly designed to determine a rotation angle, preferably the rotation angle of the first shaft or the steering shaft in an assembled state of the sensor device with the steering gear, in which the rotor is rotationally connected to the first shaft. The rotation angle can, in particular, correspond to the angle about a longitudinal axis of the steering shaft and / or the first shaft.

[0020] The Oldham coupling, also known as a Phillips-head or cross-slide coupling, is a non-switchable, torsionally rigid coupling that can compensate for a radial offset between two parallel shafts. In an assembled state, in which the sensor device is connected to the steering gear, the Oldham coupling can compensate for the radial offset of the rotor from the first shaft, so that they can be connected to each other in a torsionally rigid manner. The Oldham coupling can essentially consist of three components: two outer components and an intermediate component. One outer component, referred to as the first interface of the Oldham coupling, can be connected to the first shaft in a backlash-free or (torsionally) rigid manner, preferably axially to the axial end piece of the first shaft. The other, outer component, referred to as the second interface of the Oldham coupling, is connected to the rotor in a (torsionally) rigid or backlash-free manner.The intermediate component, for example, an intermediate disk, can form a sliding joint with the first and second interfaces. The intermediate disk can, for example, have a central strip on each of its circular surfaces, which engages in a groove of the interfaces in the manner of an axially movable tongue and groove connection. The strips of the intermediate disk intersect, in particular, at right angles (cross-slide).

[0021] If a radial misalignment occurs between the first shaft and the disc, the intermediate disc assumes a position dependent on the rotational position of the coupling. In the general rotational position, a displacement has occurred in both sliding joints. Only in the preferred positions, in which one of the two sliding joints is in the direction of the misalignment, is the other sliding joint in the center position.

[0022] The rotational transmission from the first shaft to the rotor is particularly accurate. The angle of rotation of the steering shaft thus corresponds exactly to the angle of rotation of the disc. In particular, by determining the angle of rotation of the rotor of the sensor device, the angle of rotation of the steering shaft or the first shaft, and thus the steering angle of the steering gear, can be precisely determined.

[0023] One embodiment provides that the rotor has a first magnetic element whose rotation angle can be determined by a first magnetic sensor of the sensor device. The first magnetic element is preferably arranged centrally and rotationally rigidly on the rotor or integrated into the rotor, with the magnetic sensor preferably being arranged on a circuit board of the sensor device so that a relative rotation between the magnetic element and the magnetic sensor can be detected. The rotation angle of the rotor can thus advantageously be determined precisely and reliably, since the magnetic element is mounted for rotation by means of the rotor without play.

[0024] In particular, the rotation of the rotor can determine a changed magnetic field of the magnetic element, with the direction of the magnetic field changing in particular, so that the angle of rotation can be determined from this. The first magnetic element can be a permanent magnet, for example, in the form of a bar magnet. The magnetic sensor can be designed, for example, as a Hall sensor, which is designed to detect an electronic flux density dependent on the rotating magnetic field. The Hall sensor can thus provide a sensor signal dependent on the steering angle or rotation angle.

[0025] In particular, "free from play" can be understood here and below to mean that the connection is not a clearance fit, but preferably an interference fit. A fixed connection can be understood here and below to mean that the connection has no degrees of freedom. A fixed connection can be understood, for example, as a joint, screw connection, or a connection with an interference fit.

[0026] One embodiment provides that the rotor is a gear that engages with at least one pinion of the sensor device. The pinion, in particular centrally, has a second magnetic element whose rotation angle can be determined by a second magnetic sensor of the sensor device. In particular, the rotation angle of the pinion corresponds to a multiple of the rotation angle of the rotor. The at least one pinion is smaller than the rotor and has fewer teeth. Thus, by utilizing the vernier principle based on the transmission ratio of the rotor to the at least one pinion, the steering angle can advantageously be determined even more precisely. The at least one pinion engages the rotor, in particular, without play, so that torque can be transmitted without hysteresis. The second magnetic element of the pinion and the associated magnetic sensor can be designed in a manner similar to the first magnetic element and the first magnetic sensor.

[0027] In combination with the first magnetic element and the first magnetic sensor of the rotor, this results in at least the advantage that a rotation angle of the rotor greater than or equal to + / - 180° can be determined.

[0028] Preferably, the gear is connected to two pinions, each of which may have a magnetic element and a different number of teeth. This results in at least the advantage that, independently of a magnetic element of the rotor, a rotation angle of the rotor greater than or equal to + / - 180° can be determined. One exemplary embodiment provides that the sensor device has a cover which is connected to the sensor device and the Oldham coupling. Preferably, the cover can be applied to a predetermined housing of the steering gear, such that the sensor device and the Oldham coupling are mounted within the housing and the rotor is connected to the first shaft, in particular to the axial end piece. As a result, in an assembled state, the sensor device and the first shaft can advantageously be protected from external influences within the housing on which the cover is applied or mounted.The arrangement of the sensor device on the first shaft is also advantageous because the first shaft, especially its axial end piece, is protected by the sensor device. An additional cover is therefore not required, allowing for a reduction in the number of components.

[0029] In particular, the cover, the sensor device, and the Oldham coupling, as well as any other components of the sensor device, are pre-assembled. The sensor device can thus form a module that can be mounted as a whole to the steering gear. This advantageously facilitates mounting the sensor device to the steering gear.

[0030] The housing can, in particular, have a first opening through which the first shaft or its axial end piece passes. The housing can, in particular, have a second opening opposite the first opening, which is designed to complement the cover. The housing can, in particular, be mounted on a housing of the steering gear or be formed integrally with the housing of the steering gear.

[0031] The cover can be screwed to the housing, for example. Any tolerance-related deviations in screw holes, which could result in a radial offset of the stub relative to the rotor, can be advantageously compensated for using the Oldham coupling.

[0032] One embodiment provides that the sensor device has a bearing sleeve with a first bearing point for the play-free, rotatable mounting of the rotor, wherein the bearing sleeve is firmly connected to the cover. The play-free, rotatable mounting of the rotor by means of the bearing sleeve advantageously allows the steering angle to be determined even more precisely. Likewise, the components of the sensor device can advantageously be pre-assembled as a module using the bearing sleeve, so that the assembly of the sensor device to the steering gear can be carried out particularly easily. One embodiment provides that the bearing sleeve has a second bearing point for the rotatable mounting of the first interface while forming a play. This advantageously enables a play-free connection between the first interface, even if concentricity errors should occur due to manufacturing or component-related issues.Due to the bearing sleeve, the first interface can advantageously be mounted with the other components of the sensor device as a module, so that the mounting of the sensor device to the steering gear can be significantly simplified.

[0033] One embodiment provides that the bearing sleeve has at least a third bearing point for the backlash-free, rotatable mounting of the at least one pinion. The backlash-free, rotatable mounting of the pinion by means of the bearing sleeve advantageously allows the steering angle to be determined even more precisely. Likewise, the components of the sensor device can advantageously be preassembled as a module using the bearing sleeve, making installation of the sensor device on the steering gear particularly easy.

[0034] One embodiment provides that the cover has an electronic connection socket for reading sensor data from the sensor device. This advantageously enables the simplest possible installation of a data cable that can be plugged into the connection socket. For example, the sensor data can be provided to a corresponding computing unit, which is designed to evaluate the sensor data and determine the steering angle of the steering gear.

[0035] One embodiment provides that the sensor device has a sealing ring for sealing the cover to the housing. The sealing ring can, in particular, be installed in a groove in the cover. When installed, the sealing ring can, for example, protect against water penetration into the housing.

[0036] A further aspect of the invention provides a steering gear for a motor vehicle. The steering gear comprises, in particular, a first shaft and a steering shaft, wherein the first shaft is motion-coupled to the steering shaft. The steering gear further comprises the sensor device according to the invention.

[0037] The sensor device is mounted, in particular, on the steering gear. In particular, the first interface is connected to the first shaft without play. Preferably, the first shaft can correspond to an axial end piece of the steering shaft, to which the first interface can be connected. In one embodiment, the cover of the sensor device is connected to the housing of the steering gear.

[0038] The steering gear allows the steering angle to be determined reliably and accurately. The steering angle can advantageously be determined indirectly by determining the rotation angle of the first shaft. The steering angle can, in particular, be directly proportional to the rotation angle of the steering shaft and / or the first shaft, so that the steering angle to be determined can be calculated directly from the determined rotation angle or directly assigned to it.

[0039] One embodiment provides that the steering gear is a steer-by-wire steering gear. Steer-by-wire is understood to be a system in automotive technology in which a steering command from a sensor (in particular the steering wheel) is transmitted exclusively electrically via one or more control units to an electromechanical actuator, which executes the steering command. In such a system, there is no mechanical connection between the steering wheel and the steered wheels; in particular, the steering shaft is not connected to a steering axle. In particular, it can be provided that an axial end piece of the steering shaft, which in a mechanical steering gear is connected to the steering wheel via a steering axle, is exposed in the steer-by-wire steering gear, so that the sensor device, in particular its first interface, can be arranged on the axial end piece of the steering shaft.

[0040] Further embodiments of the steering system according to the invention follow directly from the various embodiments of the sensor device according to the invention, and vice versa. In particular, individual features and corresponding explanations as well as advantages relating to the various embodiments of the sensor device according to the invention can be transferred analogously to corresponding embodiments of the steering system according to the invention.

[0041] A further aspect of the invention provides a motor vehicle comprising a steering gear according to the invention. The motor vehicle can preferably be a passenger car, truck, or bus.

[0042] Further features of the invention emerge from the claims, the figures, and the description of the figures. The features and combinations of features mentioned above in the description, as well as the features and combinations of features mentioned below in the description of the figures and / or shown in the figures, can be encompassed by the invention not only in the respective combination specified, but also in other combinations. In particular, the invention can also encompass embodiments and combinations of features that do not have all the features of an originally formulated claim. Furthermore, the invention can encompass embodiments and combinations of features that go beyond or deviate from the combinations of features set out in the backreferences to the claims. In this case:

[0043] Fig. 1 shows an embodiment of a steering gear from the prior art;

[0044] Fig. 2 is a schematic representation of an embodiment of a sensor device according to the invention and a steering shaft with a housing;

[0045] Fig. 3 is a schematic representation of a concentricity error between the sensor device and the steering shaft;

[0046] Fig. 4 is an exploded view of an embodiment of a sensor device according to the invention and a steering shaft with a housing;

[0047] Fig. 5 is a schematic representation of an embodiment of a motor vehicle according to the invention with a steering gear according to the invention.

[0048] Fig. 1 shows an embodiment of a steering gear 2 from the prior art. The steering gear 2 has, in particular, a first shaft 7, which in this embodiment can correspond to an axial end piece 7 of a predetermined steering shaft. The steering shaft can be connected, in particular, mechanically, for example via a gear or spindle drive and other components, to tie rods, wherein, for example, wheel suspensions or wheels of a motor vehicle can be steered by means of the tie rods. The steering gear has, in particular, a steering angle which indicates the angle by which the wheel suspensions are steered relative to a straight-ahead driving position depending on the steering position of the tie rods. A rotation angle of the first shaft 7 or the steering shaft about its longitudinal axis can, in particular, be directly assignable to the steering angle of the steering gear. For example, these are directly proportional to one another.The rotation angle of the steering shaft and the steering angle of the steering gear are particularly coupled to each other, so that the steering angle can be directly determined by determining the rotation angle.

[0049] In a mechanical steering system, the steering angle can be controlled mechanically via a steering axle, which can be connected to the stub 7 of the steering shaft and a steering wheel of the vehicle.

[0050] In a steer-by-wire steering system, the steering angle can be controlled via an electromechanical actuator, which can be connected, for example, via a belt to a spindle of the steering gear 2. A connection of the axial end piece 7 to the steering axle is thus no longer necessary, so that the axial end piece 7 can be exposed. In a particularly simple manner, the axial end piece 7 can be covered by a housing, which can be applied to a housing interface 25, so that the interior of the steering gear 2 is protected from external influences. If the actuator controls the steering gear 2 by a specific steering angle, the steering shaft inevitably rotates by a corresponding angle of rotation.

[0051] Fig. 2 shows a schematic representation of an embodiment of a sensor device 1 according to the invention for determining the steering angle of the steering gear 2 for a motor vehicle 3, and of an axial end piece 7 of a steering shaft with a housing 17 of the steering gear 2 in a non-assembled state. The axial end piece 7 can be inserted into the housing 17 via a first, round opening 22, so that the axial end piece 7 of the steering shaft is located inside the housing 17. The housing 17 can be attached to the housing interface 25 of the steering gear 2, for example, by screwing or the like (not shown here). The housing 17 has, for example, a second opening 23, through which components of the sensor device 1 can be introduced into the interior of the housing 17 and which can be closed by a cover. The housing 17 can, for example, have drilled holes for screwing to the cover.

[0052] The axial end piece 7 can in particular have a profile, for example a splined shaft profile, polygonal profile, toothed shaft profile or the like, in order to be able to be connected to a complementarily designed hub in a force-locking and / or form-locking manner, in particular free of play and (rotationally) fixed.

[0053] The sensor device 1 is shown in a preassembled state in Fig. 2. The sensor device 1 can thus be connected directly to the housing 17 and the axial end piece 7 as a module.

[0054] The sensor device 1 has in particular the sensor device 4 for determining the angle of rotation, in particular the angle of rotation of the steering shaft or the axial end piece 7 of the steering shaft, via which the coupled steering angle of the steering gear 2 can be determined.

[0055] The sensor device 1 comprises, in particular, an Oldham coupling 5. In the exemplary embodiment, the Oldham coupling 5 comprises a first interface 6 in the form of a hub for a play-free connection to the first shaft 7, in particular the axial end piece 7. The first interface 6 can, in particular, have a profile that is complementary to the profile of the stub 6, so that they can form a press fit or the like with each other.

[0056] The sensor device 1 can, in particular, have a cover 16 and a bearing sleeve 18, which is firmly connected to the cover 16. The cover 16 can also have an electronic connection socket 19, by means of which, for example, sensor signals from the sensor device 1 can be read and / or the sensor device can be controlled and / or supplied with electricity. The cover 16 can, for example, have drilled holes for screwing to the housing 17.

[0057] In an assembled state, the housing 17 and the cover 16 are firmly connected to one another, in particular screwed by means of screws 26, and the first interface 6 and the axial end piece 7 are connected to one another in a rotationally rigid and play-free manner.

[0058] Fig. 3 shows a schematic representation of a concentricity error between the sensor device 1 with a rotor 9 and the first shaft 7 or the housing 17. While such a concentricity error or radial offset is undesirable, it may be permissible due to component or manufacturing tolerances. In particular, component tolerances in the micro- or millimeter range may be permissible, for example in a range of 0.1 mm to 0.5 mm, in particular 0.3 mm. While this concentricity error could be compensated for, for example, by play in the bearing of the rotor 9 of the sensor device 4, so that the rotor 9 can be mounted directly or indirectly with the axial end piece 7, this would lead to an inaccurate determination of the angle of rotation or the steering angle, or to hysteresis.

[0059] Fig. 4 shows an exploded view of an embodiment of the sensor device 1 according to the invention and the axial end piece 7 of the steering shaft with the housing 17.

[0060] The first interface 6, which is designed, for example, as a hub for connecting to the axial end piece 7, can have a bearing recess 27 for supporting an intermediate disk 24 of the Oldham coupling 5. In the illustrated embodiment, the bearing recess 27 can have grooves into which spring elements of the intermediate disk 24 can engage, preferably without play, in the sense of a tongue-and-groove connection and can form a sliding joint along a first axis.

[0061] The second interface 8 is fixedly connected to the rotor 9 of the sensor device 4, for example, formed in one piece or integrally with the rotor 9. The second interface 8 can in turn form spring elements which can engage in grooves of the intermediate disk 24 in the sense of a tongue and groove connection, preferably without play, so that a further sliding joint can be formed along a second axis perpendicular to the first axis. By means of the intermediate disk 24, the first interface 6 and the second interface 8 can thus be connected to one another in a rotationally rigid manner while compensating for the radial offset. The rotation angle of the first interface 6 thus corresponds exactly to the rotation angle of the second interface 8.

[0062] The rotor 9 can be designed as a gear and, for example, engage with two pinions 12, 13, preferably without play. The first pinion 12, in particular, has a different number of teeth than the second gear 13. The pinions 12, 13 are, in particular, smaller than the rotor 9, so that a rotation angle of the pinions 12, 13 corresponds to a multiple of the rotor 9.

[0063] The rotor 9 can, in particular, have a central first magnetic element 10, the rotation angle of which can be determined by a first magnetic sensor of the sensor device 4. The pinions 12, 13 can, in particular, have central second magnetic elements 14, 15, the rotation angle of which can be determined by second magnetic sensors of the sensor device 4. The magnetic elements 10, 14, 15 can, in particular, be permanent magnets in the form of bar magnets, wherein changes in their magnetic field due to rotation can be detected by the magnetic sensors. The magnetic sensors can, for example, be Hall sensors. The magnetic sensors can, in particular, be mechanically fastened to a circuit board 11 and electrically connected to pins of the connection socket 19. The circuit board 11 is, in particular, firmly connected to the cover 16.

[0064] The sensor device 1 can further comprise a bearing sleeve 18, which can form bearing points for the play-free, rotatable mounting of the rotor 9 and the pinions 12, 13, as well as a bearing point for supporting the first interface 6 while forming a play, so that it can be connected to the first shaft 7 even in the event of a concentricity error. The bearing sleeve 6 can, in particular, be firmly connected to the cover and hold the described components of the sensor device 1 together as a module.

[0065] The sensor device 1 can also have a sealing ring 20, which can be mounted, for example, in an annular groove of the cover 16. When the housing 17 is assembled with the cover 16, the interior of the housing 17 can be reliably protected from external influences by means of the sealing ring 20.

[0066] Fig. 5 shows a schematic representation of an embodiment of a motor vehicle 3 according to the invention with a steering gear 2 according to the invention. The steering gear 2 has the sensor device 1 according to the invention, which is connected to the first shaft 7 in an assembled state. The steering gear 2 can preferably be a steer-by-wire steering gear, the axial end piece 7 of which is not intended to be mechanically connected to a steering axle.

[0067] Overall, the examples show how a sensor device 1 for determining the steering angle of a steering gear, in particular a steer-by-wire steering gear 2, can be provided. The sensor device 4 can have a rotor 9, on which two pinions 12, 13 (satellite gears) can be driven. Magnetic elements 14, 15 can be provided in the pinions 12, 13, so that their rotation can be detected via magnetic sensors. Furthermore, a further magnetic element 10 can be provided in the center of the rotor 9, which rotates synchronously with the steering shaft. Its rotation can also be detected via a magnetic sensor. In particular, an Oldham coupling is provided between the rotor 9 and the steering shaft or its axial end 9.

Claims

Patent claims 1. Sensor device (1) for determining a steering angle, a steering device (2) for a motor vehicle (3), wherein the sensor device (1) can be coupled to the steering device (2) via a steering shaft stub (7) and a rotor (9) of a sensor device (4) for determining the angular position of the steering shaft stub (7), characterized by - an Oldham coupling (5) having a first interface (6) for play-free connection to the steering shaft stub (7) of the steering device (2) and a second interface (8) which is fixedly connected to the rotor (9) of the sensor device (4).

2. Sensor device (1) according to claim 1, characterized in that the rotor (9), in particular centrally, has a first magnetic element (10), the angle of rotation of which can be determined by a first magnetic sensor of the sensor device (4), wherein preferably the magnetic sensor is arranged on a circuit board (11) of the sensor device (1), so that a relative rotation between the magnetic element (10) and the magnetic sensor can be detected.

3. Sensor device (1) according to claim 1 or 2, characterized in that the rotor (9) is a gear which engages with at least one pinion (12, 13) of the sensor device (4), wherein the pinion (12, 13), in particular centrally, has a second magnetic element (14, 15) whose angle of rotation can be determined by a second magnetic sensor of the sensor device (4).

4. Sensor device (1) according to one of the preceding claims, characterized by a cover (16) which is connected to the sensor device (4) and the Oldham coupling (5), wherein the cover (16) can be applied to a predetermined housing (17) of the steering gear (2) so that the sensor device (4) and the Oldham coupling (5) are mounted within the housing (16) and the rotor (9) is connected to the first shaft (7).

5. Sensor device (1) according to claim 4, characterized by a bearing sleeve (18) with a first bearing point for the play-free rotatable mounting of the rotor (9), wherein the bearing sleeve (18) is firmly connected to the cover (16).

6. Sensor device (1) according to claim 4 or 5, characterized in that the bearing sleeve (18) has a second bearing point for rotatably supporting the first interface (6) while forming a play.

7. Sensor device (1) according to one of claims 4 to 6, characterized in that the bearing sleeve (18) has at least one third bearing point for the play-free rotatable mounting of the at least one pinion (12, 13).

8. Sensor device (1) according to one of claims 4 to 7, characterized in that the cover (16) has an electronic connection socket (19) for reading out sensor data of the sensor device (1).

9. Sensor device (1) according to one of claims 4 to 8, characterized by a sealing ring (20) for sealing the cover (16) to the housing (17).

10. Sensor device (1) according to one of the preceding claims, characterized in that the first interface (6) is a hub which can be axially mounted on the first shaft (7).

11. Steering gear (2) for a motor vehicle (3), comprising a first steering shaft stub (7) and a push rod for controlling a tie rod of a motor vehicle (3), wherein the first steering shaft stub (7) is motion-coupled to the tie rod, characterized in that a sensor device (1) according to one of the preceding claims is arranged on the steering shaft stub (7).

12. Steering gear (2) according to claim 11, characterized in that the steering gear (2) is a steer-by-wire steering gear.

13. Motor vehicle (3), characterized by a steering gear (2) according to claim 11 or 12.

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