Position fixing device

Abstract

A device is disclosed for fixing the position of a rotation angle sensor, which determines the rotation angle between the rotor and the stator, relative to a sensor carrier centered on the rotation axis. [Solution] The device (40) comprises a base (48), a torsional rigidity support bearing (52) for receiving torsional force from a rotation angle sensor (9) when viewed from a circumferential direction (44) about the axis of rotation, and a spring (50) held by the support bearing, configured to apply a restoring force to the sensor carrier, having at least one spring foot (56) and a spring arm (54) that extends at least partially axially (42) with respect to the axis of rotation, wherein the spring arm includes a spring arm side oriented forward when viewed from a circumferential direction about the axis of rotation, and a spring arm side (60) oriented rearward opposite to the spring arm side (58), and the spring foot and at least one of the spring arm sides are disposed within the base.

Description

TECHNICAL FIELD

[0001] The present invention relates to a position fixing device based on the preamble of current claim 1.

BACKGROUND ART

[0002] Such a device is known from DE 10 2022 103 722 A1.

SUMMARY OF THE INVENTION

[0003] The object of the present invention is to improve the known device.

[0004] This object is solved by the features of the independent claim. Preferred further developments are the subject of the dependent claims.

[0005] On the premise of a position fixing device for a rotation angle sensor that determines the rotation angle between a rotor and a stator relative to a sensor carrier centered on a rotation axis, the device includes a base body, a torsionally rigid support bearing for receiving torsional force from the rotation angle sensor when viewed in the circumferential direction around the rotation axis, and a spring configured to apply a restoring force to the sensor carrier. The spring has at least one spring foot and a spring arm extending at least partially in the axial direction relative to the rotation axis. The spring arm comprises a spring arm side oriented forward when viewed in the circumferential direction around the rotation axis, and a spring arm side oriented rearward opposite to the forward oriented spring arm side. According to the present invention, at least one of the spring foot and the spring arm side is arranged in the base body.

[0006] The aforementioned device is based on the consideration that, in the position-fixing device described at the beginning, a spring arm is used in which the spring foot is located completely outside the support housing body or structure. Here, the spring arm is designed to have two opposing sides (one facing the base and the other facing away from the base), and as a result, the entire spring arm, including the mounting point, is mounted circumferentially outside the support structure. In this arrangement, the spring foot is oriented forward or backward in the circumferential direction around the axis of rotation, and therefore the force transmission acts along the circumferential direction, resulting in an unfavorable stress distribution in the region of the spring foot, and as a result, the material stress due to the torsion of the spring foot is concentrated in the V-shaped notch between the spring arm and the base. Repeated torsional loads can lead to material fatigue and cracking in the long term.

[0007] Here, the device is based on the consideration that by rearranging the direction of force introduction and structurally integrating the spring foot, material stress in the region of the spring foot is better distributed in the circumferential direction around torsional motion. According to the present invention, this is achieved by arranging at least one of the spring foot and spring arm sides within the base, so that the spring arm is no longer attached to the outside of the base in the circumferential direction, but is housed within the support structure in the axial direction. This orientation of the spring foot in the rotational axis direction improves the distribution of mechanical stress in the transition region between the spring arm and the base in the spring foot. In this case, the torsional force is no longer introduced into the structure via an axially oriented clamping region, rather than via a tangential contact path. The axial orientation allows for force transmission over a wider area to deeper material zones in the base, thereby significantly reducing local stress peaks in the spring foot region. At the same time, integration into the base forms a geometric guide that restricts the movement of the spring arm and prevents overloading due to excessive deflection. Additional restricting walls are no longer necessary in principle. The tightening within the base creates a more stable and directionally optimized load path, enabling the design of a load-appropriate anti-rotation fixing that could not be achieved with the known tangential mounting of the device described at the beginning.

[0008] By reducing stress peaks, material fatigue, and uncontrollable spring stroke overshoot in the spring foot region, the device of the present invention can significantly reduce the failure rate during operation. The transmission of varied forces via an axially oriented spring foot embedded within the base results in a more uniform stress distribution, particularly reducing locally concentrated load peaks that have been identified as causes of crack formation and failure in known structures. This positively impacts the overall fatigue strength of the component, extending its service life even under repeated loads and thermal loads. Geometric guidance of the spring arm within the base ensures that the spring arm's movement path remains controlled, further ensuring that mechanical overload due to excessive deflection is avoided. Overall, because functionally important load points are geometrically defined and structurally protected, a robust, mass-production stable solution is obtained, resulting in high failure safety, low maintenance requirements, improved manufacturing tolerances, and reduced overall reliability.

[0009] In a further developmental form, the base body comprises a circumferential base wall in which a spring arm is positioned with respect to the axial axis of rotation. In this way, the spring arm can be completely enclosed by the supporting hollow structure. This not only enables secure and defined axial clamping but also simultaneously provides geometric guidance and mechanical constraints for the spring arm. The circumferential wall allows for the specific definition of the spring arm's movement space, mechanically preventing overload due to excessive deflection. Furthermore, the spring arm is reliably protected from external influences such as dirt, mechanical contact, and thermal peaks by the surrounding base wall. The hollow structure also allows for space-optimized integration into existing housing shapes and provides structural freedom for the arrangement of multiple spring arms or sensor components. There are also manufacturing advantages, as the wall structure can be manufactured particularly efficiently as a rotationally symmetric or segmented injection-molded part within a sealed mold.

[0010] In a further developmental form, the base wall is configured to have a recess when viewed from the axial direction of the rotation axis, within which the spring arm is positioned. In this way, the spring arm is not only spatially guided within the base but is also further accommodated by a structure restricted in the lateral and / or axial directions, thereby enabling precise and directional guidance of the spring arm. The placement within the recess improves the structural integration of the spring arm. This is because stress from the spring arm can be introduced into the surrounding wall structure in a controlled manner, rather than concentrating at external connection points. Furthermore, the geometric shape of the recess allows for the achievement of defined movement limits of the spring arm, preventing undesirable excessive deflection and thereby extending the service life of the component. The recessed placement within the wall structure improves the protection of the spring arm against mechanical damage and environmental impacts, while simultaneously creating structural degrees of freedom for further integration possibilities, such as accommodating additional guide or damping elements.

[0011] In a more advantageous embodiment, the spring foot is configured to be positioned at the bottom of the recess when viewed from the axial direction of the rotation axis. In this way, the spring arm is introduced axially from its foot region into the substrate structure and fixed there over a certain area. Thus, force introduction occurs along the rotation axis in the direction of the depth of the recess wall, thereby achieving particularly stable clamping with a uniform stress distribution. The bottom embedding allows for low-loss return of bending and torsional forces to the surrounding material structure, minimizing critical stress peaks that occur in clamping configurations mounted tangentially or laterally. Furthermore, this creates a structurally clear separation between the active spring region and the passive force-absorbing section of the substrate, which is advantageous for both spatial arrangement and repeatability in the manufacturing process.

[0012] Furthermore, the spring arm may be configured to be oriented parallel to the base wall when relaxed. In this way, a positionally optimized resting position for the spring arm is obtained. In this case, the spring arm is guided along the wall structure over a certain area when unloaded or without deflection. The parallel orientation not only improves the guidance of the spring arm within the recess but also contributes to particularly compact space design because the spring arm does not occupy additional volume outside the wall contour when unloaded. Moreover, this geometric shape simplifies manufacturing because the geometric shape of the spring arm can be easily incorporated by tool forms that guide it rotationally or linearly. The parallel orientation also supports a defined and reproducible deflection characteristic when a force is applied because the direction of deflection is precisely perpendicular to the original installation position.

[0013] In a further advantageous embodiment, reinforcing ribs, preferably oriented radially with respect to the axis of rotation, are arranged within the base wall. In this way, the mechanical rigidity of the wall structure can be intentionally improved, particularly in the radial direction where bending and shear forces can be generated by the action of the spring arm during deflection. The reinforcing ribs act as structural counter-supports that prevent deformation or unwanted deflection of the wall structure, while simultaneously assisting in the reception and dissipation of these forces. As a result, the position of the spring arm within the recess is stabilized, and the spring's restoring characteristics are kept constant even under prolonged loads and temperature fluctuations. The reinforcing ribs can further function as guide elements or contact surfaces for restricting the movement of the spring arm, thereby structurally extending the functional range of the component.

[0014] In a more preferred embodiment, the base wall is concave in the region of the support bearing when viewed from the axis of rotation. In this way, the support bearing is embedded in a shape-fit into a receiving structure of the corresponding shape, thereby enabling the component to self-center during assembly and to be reliably positioned against relative rotation. The concave shape supports a uniform distribution of circumferential forces, thereby promoting large-area contact behavior and reducing localized load concentration. Particularly when subjected to circumferential torsional moments, the concave geometric shape results in improved force flow to adjacent wall regions, increasing the torsional rigidity of the overall structure. Furthermore, the concave formation can be used as a defined contact surface for additional fixing elements, such as locking lugs or mating structures.

[0015] In yet another embodiment, the base wall has a bulge directed inward into the internal space enclosed by the base wall, on the side opposite the support bearing when viewed from the axis of rotation. In this way, a locally protruding structure is formed in the internal space, which serves the purpose of targeted reinforcement, functional extension, or geometric fit. Thereafter, the bulge can be used as a contact surface or limiting surface for a spring arm, for example, for defined movement limiting or for positioning in an unloaded state. At the same time, the bulge acts structurally as additional reinforcement of the wall structure by increasing axial bending stiffness and supporting the dimensional stability of the internal space. The bulge can further function to accommodate additional functional elements, such as damping zones, guide protrusions, or integrated rocking lugs. A more uniform material distribution within the base wall is additionally achieved through the targeted arrangement on the side opposite the support bearing, which reduces stress differences under torsional loads.

[0016] In yet another embodiment, the base has stop walls circumferentially oriented on the rear and / or front sides when viewed from the circumferential direction around the axis of rotation. In this way, defined mechanical limits are formed that restrict the movement of either the spring arm or the entire housing or the base relative to the sensor carrier. The stop walls act as shape-fitting retaining elements during circumferential deflection, preventing the spring from being subjected to stress beyond its intended operating range. This contributes to the extended lifespan of the component and reduces the risk of material fatigue due to excessive deformation. Depending on the front and / or rear arrangement, the stop walls can function as one-sided or both-sided end stops and can optionally be used for adjusting or locking the component in the installed state. Furthermore, it supports spatially defined integration into the surrounding housing or bearing structure.

[0017] According to yet another aspect of the present invention, a rotation angle sensor for detecting the rotation angle between a rotor and a stator comprises a rotor, a stator having a housing and a circuit board, and one of the devices for fixing the rotational position of the housing relative to a sensor carrier about a rotation axis, the circuit board for evaluating the encoder field affected by the rotor. Integrating one of the devices for position fixing into the rotation angle sensor provides several advantages to the sensor function itself. In particular, a structurally stable connection with a defined housing orientation enables repeatable fixing of the stator position relative to the rotor, thereby improving the measurement accuracy, repeatability, and thermal stability of the sensor. Furthermore, the long-term stability of calibration is improved and the assembly process is simplified, which positively impacts the reliability of the entire sensor system. [Brief explanation of the drawing]

[0018] The characteristics, features, and advantages of the present invention described above, as well as the methods for realizing them, will become more readily apparent in connection with the following description of embodiments, which will be explained in more detail with reference to the drawings. The drawings show the following: [Figure 1] This is a structural diagram of a vehicle equipped with sensors for detecting rotation angle and torque. [Figure 2] Figure 1 is a structural diagram of the sensor used to detect the rotation angle and torque. [Figure 3a] This is a structural diagram of a conventional device for fixing the position of the sensor shown in Figure 1 inside a vehicle. [Figure 3b] This is a structural diagram of the device according to the present invention for fixing the position of the sensor shown in Figure 1 inside a vehicle. [Figure 4] This is a perspective view of the apparatus according to the present invention according to the first embodiment. [Figure 5] This is a perspective view of the apparatus according to the present invention according to a second embodiment.

[0019] In the drawings, identical technical elements are assigned the same reference number and are described only once. The drawings are merely schematic and do not, in particular, show actual geometric relationships. [Modes for carrying out the invention]

[0020] Please refer to Figure 1, a schematic perspective view showing vehicle 1 equipped with steering system 2.

[0021] In this embodiment, the vehicle 1 comprises a chassis 5 supported by two front wheels 3 and two rear wheels 4. The front wheels 3 are steerable via a steering system 2, thereby enabling the vehicle 1 to turn corners.

[0022] The steering system 2 includes a steering handle 6 mounted on a first steering shaft 7, and the first steering shaft 7 is arranged to be rotatable about a rotation axis 8. The first steering shaft 7 is guided to a sensor 9 for detecting a position, here an angular position, and is further connected to a torsion element 10 in an unspecified manner. The torsion element has a freely selectable spring stiffness (which is preferably selected to be constant and linear), whereby an applied torque is converted into a measurable torque angle. A second steering shaft 11 is connected to the torsion element 10 on the side opposite to the first steering shaft 7 on the rotation axis 8, and the second steering shaft 11 is further connected to a steering gear 12 at its distal end. When the steering handle 6 is rotated with a torque in the form of steering torque 13, the steering torque 13 is transmitted to the steering gear 12 via the steering shafts 7 and 11 accordingly, and in response, the steering gear 12 steers the front wheels 3 at a wheel steering angle 14 for turning.

[0023] The steering operation is assisted by an assist motor 15 that causes the second steering shaft 11 to co-rotate. For this purpose, the steering torque 13 is derived from the rotational angle difference 16 between the first steering shaft 7 and the second steering shaft 11 detected by the inductive sensor 9. Next, the assist motor 15 rotates, inter alia, the second steering shaft 11 as a function of the detected steering torque 13.

[0024] In order to detect the aforementioned rotational angle difference 16, and thus the steering torque 13, the sensor 9 includes a fine track 17 connected to the first steering shaft 7 and a coarse track 18 connected to the second steering shaft 11. This will be explained in more detail later. The sensor 9 further includes a measurement circuit 19 fixed at a fixed position relative to the vehicle 1, and the measurement circuit 19 detects the angular position of the fine track 17 and the angular position of the coarse track 18, and determines the rotational angle difference 16 therefrom. This will also be explained in more detail later. Based on the rotational angle difference 16, the control unit 20 can control the assist motor 15 with an appropriate control signal 21.

[0025] In addition to the rotation angle difference 16, the measurement circuit 19 of the sensor 9 also determines the rotation angle 22 of the entire steering shaft 7, 11, for example, for use in a vehicle dynamics system.

[0026] The structure of the sensor 9, which serves as the basis for the description of the present embodiment, will be described in detail below with reference to Figure 2.

[0027] The coarse track 18 is directly fastened to the second steering shaft 11 in a rotationally fixed state, while the fine track 17 is held on the first steering shaft 7 via a carrier sleeve 23. Furthermore, a drive wheel 24 is held on this carrier sleeve 23 such that its rotation is fixed, and drives the driven wheel 25 of the multi-rotation angle detection device 26 in a manner to be described later.

[0028] In the present embodiment, the fine track 17 is designed as a vane wheel having a plurality of metallic fine track vanes 27. The individual fine track vanes 27 are arranged at equal intervals in the circumferential direction of the first steering shaft 7, and are held on a fine track carrier 28. For further explanation, although far more fine track vanes 27 are shown in Figure 2, the description is given on the assumption that there are 12 fine track vanes 27.

[0029] Similarly, the coarse track 18 of the present embodiment is also designed as a vane wheel having a plurality of metallic coarse track vanes 29. The individual coarse track vanes 29 are likewise arranged at equal intervals in the circumferential direction of the first steering shaft 7, and are held on a coarse track carrier 30 in the same manner as the fine track 17. In the following description, the description is given on the assumption that there are 8 coarse track vanes 29. Not all of these coarse track vanes 29 are visible from the viewpoint of Figure 2.

[0030] The measurement circuit 19 can determine the rotation angle 22 using the coarse track vane 29 and the fine track vane 27. For this purpose, the measurement circuit 19 can, in principle, be configured as described in EP 3 865 824 A1.

[0031] The measurement circuit 19 has a FineTrack side 31 directed toward the FineTrack vane 27 and a CoastTrack side 32 directed toward the CoastTrack vane 29. Each side of the measurement circuit 19 is preferably provided with a transmitting coil (not shown in detail) that excites a high-frequency magnetic field and at least one receiving coil (not shown in detail) from which a voltage is induced by the magnetic field. On the FineTrack side 31, a FineTrack signal is generated in the corresponding receiving coil, while on the CoastTrack side 32, a CoastTrack signal is generated in the corresponding receiving coil.

[0032] In this configuration of the measurement circuit 19, the vanes 27 and 29 disturb the magnetic fields generated by their respective transmitting coils, thereby causing the finetrack and coarsetrack signals to change according to the rotation angles of the respective tracks 17 and 18. This basic configuration is expandable, for example, to make the measurement system more robust against measurement errors. Such expansions are discussed in EP 3 865 824 A1 above. However, such expansions are not relevant to understanding this embodiment.

[0033] The only important point to understand in this embodiment is that the vanes 27 and 29 of tracks 17 and 18 generate track signals that change periodically depending on the angular position of each track 17 and 18.

[0034] In addition to the track signal, the multi-turn angle detection device 26 also outputs a magnetic angle signal. This magnetic angle signal is generated by a magnetic sensor element 37 based on a radially magnetized magnet 36. This magnet 36 is positioned on the side of the driven wheel 25 facing the circuit board 19 and rotates above the magnetic sensor element 37 by the driven wheel 25.

[0035] From the track signal and magnetic angle signal, the total rotation angle 22 of the steering shafts 7 and 11 is calculated on the circuit board 19 and output via the output interface 38. In the sensor 9 described above, the measurement circuit 19 is fixed in a predetermined position relative to the vehicle 1, and therefore fixed relative to the rotation axis 8. In order to accurately detect the angular position of the Fine Track 17 and the Coast Track 18, the measurement circuit 19, and by extension the housing on which it is mounted, must be precisely fixed in a rotational position relative to the rotation of the rotation axis 8.

[0036] This must be achieved by appropriate anti-rotation fixing means in the circumferential direction, i.e., around the rotation axis 8, but challenges also arise in fixing the radial position of the housing relative to the rotation axis 8. This is because manufacturing tolerances, thermal expansion, or installation forces can lead to radial displacement or tilting of the housing, resulting in displacement of the transmitting and receiving coils of the measuring circuit 19 relative to the vanes 27, 29 or magnets 36.

[0037] Such radial misalignments can cause changes in the coupling characteristics between the coil and the track vane, especially when using high-frequency magnetic fields, which can affect the amplitude and phase position of the received track signal. This is also true for the magnetic angle signal of the magnetic sensor element 37. Even small misalignments in the sub-millimeter range can cause systematic measurement errors and increased temperature sensitivity in the angle signal.

[0038] Given this background, precise and permanently stable radial positioning of the measurement circuit 19 relative to the sensor carrier fixed in place on the chassis 5 of vehicle 1 is of particular importance. Radial misalignment of the measurement circuit 19 can lead to displacement of the transmitting and receiving coils of the measurement circuit 19 relative to the fine track vanes 27, coarse track vanes 29, or magnets 36, for example, as a result of manufacturing tolerances, temperature effects, or mechanical loads in the installed state. This displacement affects the coupling between the coils and vane structures or the magnetic field, which can change the amplitude, phase position, or linearity of the detected track signal and magnetic angle signal. To avoid this, the measurement circuit 19 must be held in position and shape-fitted relative to the sensor carrier and, consequently, the chassis 5.

[0039] For this purpose, a sensor 9 is used within the vehicle 1, on a sensor carrier and, consequently, on the chassis 5. This position-fixing device 40 will first be described with reference to Figures 3a and 3b. Figure 3a shows the principle of a conventional device 39 known from DE 10 2022 103 722 A1, and Figure 3b shows the device 40 according to the present invention. To simplify the following explanation, the devices 39 and 40 will be considered below in a cylindrical coordinate system having an axial direction 42 extending parallel to the rotation axis 8, a circumferential direction 44 extending circumferentially around the rotation axis 8, and a radial direction 46 extending laterally with respect to the axial direction 42 and laterally with respect to the circumferential direction 44. To understand the function, it is important that the sensor 9 does not necessarily need to be located in the circumferential direction 44 behind the devices 39 and 40. During operation, the sensor 9 is generally located behind the devices 39 and 40 when viewed from the radial direction 46. This is specifically shown in Figures 4 and 5 below.

[0040] Both the conventional device 39 and the device 40 according to the present invention include a base 48 and a spring 50 held on the base 48 via a support bearing 52. The spring 50 is intended to provide a restoring force to the sensor carrier, and by extension the chassis 5, in the opposite direction to the circumferential direction 44, in order to firmly position the sensor 9 in the circumferential direction 44 as described above.

[0041] Similar to DE 10 2022 103 722 A1, the possibility of providing a restoring force by a spring independent of the base 48 is costly, complex to manufacture, and requires maintenance. Therefore, it has been proposed to manufacture the spring 50 integrally with the base 48. The spring 50 of this known device 39 has a spring arm 54 connected to a support bearing 52 and, by extension, the base 48 via a spring foot 56.

[0042] Conventional devices 39 have a first spring arm side 58 directed toward the sensor carrier and, consequently, the chassis 5, when viewed from the circumferential direction 44, and a second spring arm side 60 directed toward the base body 48. DE 10 2022 103 722 A1 teaches that the second spring arm side must be directed toward the base body 48, and as a result, the entire spring foot 56 and support bearing 52 must be located in front of the base body 48 when viewed from the circumferential direction 44, and the spring arm 54 must extend at an acute angle to the base body 48, otherwise a restoring force cannot be applied.

[0043] However, this acute angle arrangement of the spring arm 54 with respect to the base 48 and the axial direction 42, and consequently the rotation axis 8, has several unfavorable effects. First, the acute angle between the strike direction of the spring arm 54 and the axial direction 42 causes an unfavorable force flow in the region of the spring foot 56. The restoring force applied by the spring 50 must act substantially opposite to the circumferential direction 44, while the spring arm 54 enters the base 48 at a sharply inclined angle. As a result, torsional and bending loads are generated, particularly at the acute angle in the region of the spring foot 56, and these loads are significantly greater than the mechanical load on the underside opposite the conventional device 39 when viewed from the axial direction 42. This results in an unfavorable redirection of forces, causing localized stress increases in the material at the acute angle and significantly increasing the risk of material fatigue and crack formation in the transition region between the spring foot 56 and the support bearing 52.

[0044] Furthermore, the acute-angle arrangement requires a long, diagonally extending spring arm 54 to allow for even a small amount of the desired restoring force in the direction opposite to the circumferential direction 44. This has an adverse effect on the absolutely necessary installation space, as the spring 50 needs to extend significantly away from the base 48 in both the circumferential direction 44 and the axial direction 42 in order to position the spring head sufficiently away from the base 48 on the opposite side of the spring foot 56. The smaller the installation space, the more difficult it becomes to integrate the sensor 9 into a correspondingly compact module or housing shape.

[0045] Finally, the geometrically acute-angle configuration restricts the movement path of the spring arm in the primary deflection direction. When deflecting in the direction of the sensor carrier, a sharp increase in bending load occurs, which can limit the effective spring action and increase the risk of overload due to shocks or continuous loads.

[0046] Here, the device 40 according to the present invention addresses this problem by arranging the spring foot 56 and at least the second spring arm side 60 within the base body 48. This arrangement makes it possible to align the spring arm 54 in a direction substantially perpendicular to the circumferential direction 44, and as a result, when the sensor carrier rotates, the spring arm moves along a line perpendicular to the direction of the applied restoring force. This has several technical advantages.

[0047] Firstly, this transmits the restoring force of the spring 50 laterally to the main extending direction of the spring arm 54, thereby achieving a material load suitable for the force flow. The bending load is uniformly distributed throughout the support bearing 52, thereby reducing stress peaks within the material.

[0048] Secondly, by adopting a right-angle geometric shape, a shorter and more compact spring structure can be realized in which force is transmitted in a more linear and clear manner. The spring characteristics are easier to determine in terms of dimensions because there are no diagonal bending paths that affect the restoring force in a non-linear manner. As a result, the reproducibility of the spring behavior is improved, especially under temperature changes and continuous dynamic loads during operation. Furthermore, the right-angle mounting position on the base 48 can be implemented more easily and robustly from a manufacturing standpoint. This is because the shape provides a clearly defined wall relationship in which the spring can be guided and supported.

[0049] A specific embodiment of the apparatus 40 according to the present invention will be described below with reference to Figure 4.

[0050] The base of the device 40 in Figure 4 is essentially a hollow cylindrical structure, having a base wall 62 that extends circumferentially around an axial direction 42, with the base wall 62 separating the internal space 64 from the external space 66. As already mentioned above, the spring 50 is located on the front side of the device 40 when viewed from the circumferential direction 44, while the device 40 is attached to the sensor 9 on the rear side when viewed from the radial direction 46. The attachment may be done by fastening means, or it may be done by an integrated configuration with several parts of the sensor 9, such as a housing that surrounds the component.

[0051] It should be understood that, due to the integrated design, the base body 48, along with the optional sensor components, is manufactured from a continuous material body through a single molding process, particularly injection molding, without requiring subsequent joining processes such as adhesive bonding, screwing, or clipping. Such an integrated design ensures a mechanically coupled, tolerance-free connection between the device 40 and the sensor 9, thereby ensuring precise and permanently stable positioning. At the same time, the reduced assembly work is particularly advantageous from the perspective of an automated production line.

[0052] A further advantage of the integrated design lies in the fact that the force flow from the spring 50 can be directly introduced into the surrounding sensor structure without the need for transitions in materials or geometric shapes that could introduce potential weaknesses. This improves the mechanical robustness of the entire sensor assembly and extends its service life under repeated loading. Furthermore, the integrated design provides structural freedom to form additional features such as seal lips, locking lugs, or plug contours as a single unit.

[0053] On the front side as viewed from the radial direction 46, the base wall 62 has a concave bulge 68 extending into the internal space toward the front side as viewed from the radial direction 46, in the region of the connection point to the sensor 9. Similarly, the outer wall as viewed from the radial direction 46 has another bulge 70 extending into the internal space 64, and as a result the two bulges 68 and 70 face each other and are opposed to each other at their respective maximum portions, which are not specifically referenced. At these maximum portions, the internal space 64 of the base 48 is supported by the support wall 72.

[0054] The concave bulges 68, 70 and their connection by the support wall 72 specifically act as local reinforcing units that stabilize the base wall in the region of the connection point. This shape forms a double-shell structure with support-like connections that has an effect comparable to a local rib or sandwich structure. In particular, under torsional or bending loads on the base, the support wall can introduce the generated force into the surrounding wall structure over a certain area, thereby avoiding stress concentration and reducing material fatigue.

[0055] The connection point to the sensor 9 is located on the rear side of the device 40 when viewed from the radial direction 56, and thus functions as the central point of force transmission between the sensor 9 and the device 40. The support in the widest region of the bulge supports the mechanical connection and ensures the directed return of the forces introduced therein, particularly the forces introduced from the spring arm 54. In this context, the bulge functions as a volume that guides the flow of force, similar to a shaped fitting or a shaped load path guide.

[0056] The concave shape on both sides of the base wall 62 allows the material to be positioned in a manner suitable for the load without requiring a large wall thickness. This reduces weight and material costs while maintaining high rigidity. The symmetrical shape further supports uniform part cooling during injection molding, reducing the risk of sink marks or warping.

[0057] The concave bulge also functions as an assembly or guiding component, for example, for axial positioning in a sensor carrier, or as a contact surface for seals, locking lugs, or guide sleeves. A defined contact surface is also obtained via the central support wall, which can be used for additional functional elements such as clips and centering pins.

[0058] The base wall 62 has an axial recess 74 on its front side when viewed from the circumferential direction 44, which extends upward from the bottom when viewed from the axial direction 42. The axial recess 74 has a recess bottom 76 positioned at its upper end when viewed from the axial direction 42, and the recess bottom 76 connects to the rest of the base wall 62 in the radial direction 64. At this recess bottom 76, the spring 50 is erected, or rather suspended, in the opposite direction to the axial direction 42, so that the recess bottom 76 functions as a support bearing at this location. In the relaxed state, the spring 50, with its spring arm 54, is positioned at the same level as the base wall 62 when viewed from the circumferential direction 44, and can pivot both into the internal space 64 and the external space 66.

[0059] If it is necessary to protect the spring 50 from overstretching, the movement of the spring 50 in the direction opposite to the circumferential direction 44 may be restricted by the proper arrangement of the support wall 72 or by additional stopping means.

[0060] For fixing in the axial direction 42, a hook 78 may be formed on the end of the spring 50 opposite to the spring foot 56. The hook 78 forms an undercut that, when viewed from the direction opposite to the axial direction 42, can engage in a shape-fit with the corresponding counter element on the sensor carrier which is fixedly held to the chassis 5. For rough positioning of the device 40, a positioning wall 80 extending in the circumferential direction 44 and the direction opposite to the circumferential direction 44 may be formed on the base 48.

[0061] Next, with reference to Figure 5, a further developed form of the device 40 will be described. In this form, the spring arm 54 of the spring 50 has a spring foot 56 at its end when viewed from the axial direction 42, and as a result, the spring 50 is fixed to the base body 48 at both ends. Elasticity is achieved by dividing the recess bottom 76 described above, and as a result, two recesses 74 are formed that extend into the base body wall 62 in opposite directions when viewed from the axial direction 42, ultimately forming two recess bottoms 76.

[0062] In this way, the spring arm 54 is formed not as a freely protruding cantilever beam, but as a bent beam structure clamped at both ends, resulting in a more symmetrical stress distribution within the material and thereby improving fatigue strength. The transition region of the spring foot 56 to the recess bottom 76 is geometrically protected by the extended form of the base wall 62 in Figure 5 and embedded in a manner optimized for the flow of force, thereby further reducing the risk of localized stress peaks and fatigue failure.

[0063] Furthermore, the double mounting allows for a more clearly defined kinematic motion of the spring arm 54, as the load is applied symmetrically and released during deflection in the circumferential direction 44. This improves the restoring behavior and enhances the reproducibility of the spring characteristics under thermal and dynamic loads. In addition, by integrating both mounting points into the wall structure of the base body 48, the spring arm 54 is completely guided within the wall thickness of the base body wall 62, enabling a very compact configuration.

[0064] Furthermore, double-sided anchoring creates the possibility of integrating additional functional elements such as damping elements, stops, or positioning aids between the two mounting points. Thus, the spring 50 not only transmits a restoring force to the sensor carrier but also becomes a structural component that actively contributes to the mechanical stability of the device 40. [Explanation of Symbols]

[0065] 1 vehicle 2. Steering System 3 Front wheels 4 Rear wheels 5 Chassis 6. Steering wheel 7. First steering shaft 8 rotation axes 9 sensors 10 torsion elements 11. Second steering shaft 12 Steering gear 13 Steering Torque 14 Wheel steering angle 15 Auxiliary motor 16 rotational angle difference 17 FineTrack 18 Coast Track 19 Measurement circuit 20 Control Units 21 Control signals 22 rotation angles (total steering shaft) 23 Carrier Sleeves 24 drive wheels 25 Driven wheels 26 Multi-rotation angle detection device 27 FineTrack Vane 28 FineTrack Carrier 29 Coast Track Vane 30 Coast Truck Carrier 31 FineTrack side 32 Coast Track side 33 Fine Track Signal 34 Coast Track Signal 36 Magnets 37 Magnetic sensor element 38 Output Interfaces 39 Conventional device 40 Apparatus according to the present invention 42 Axis 44 Circumferential direction 46 Radial 48 Substrate 50 springs 52 Support bearings 54 Spring Arm 56 Spring Foot 58 First spring arm side 60 Second spring arm side 62 Base wall 64 Interior space 66 External space 68 Inner bulge 70 Outer bulge 72 Support wall 74 Axial recess 76 Recessed bottom 78 hooks 80 Positioning wall

Claims

1. A device (40) for fixing the position of a rotation angle sensor (9), which determines the rotation angle between the rotor and the stator, relative to a sensor carrier centered on the rotation axis (8), - Substrate (48), - A support bearing (52) with torsional rigidity to receive the torsional force from the rotation angle sensor (9), viewed from the circumferential direction (44) centered on the rotation axis (8), - A spring (50) held by the support bearing (52), configured to apply a restoring force to the sensor carrier, having at least one spring foot (56) and a spring arm (54) that extends at least partially axially (42) with respect to the rotation axis (8), wherein the spring arm (54) comprises a spring (50) including a spring arm side (58) oriented forward when viewed from the circumferential direction (44) about the rotation axis (8) and a spring arm side (60) oriented rearward opposite to the spring arm side, - The device (40) is characterized in that at least one of the spring foot (56) and the spring arm side (58, 60) is arranged within the base (48).

2. The apparatus (40) according to claim 1, characterized in that the base body (48) has a base body wall (62) in the axial direction (42) with respect to the rotation axis (8), and the spring arm (54) is arranged within the base body wall (62).

3. The apparatus (40) according to claim 2, characterized in that the base wall (62) has a recess (74) when viewed from the axial direction (42) of the rotation axis (8), and the spring arm (54) is arranged in the recess (74).

4. The apparatus (40) according to claim 3, characterized in that the spring foot (56) is positioned on the bottom side (76) of the recess (74) when viewed from the axial direction (42) of the rotating shaft (8).

5. The device (40) according to any one of claims 2 to 4, characterized in that the spring arm (54) is oriented parallel to the base wall (62) when in a relaxed state.

6. The apparatus (40) according to any one of claims 2 to 4, characterized in that reinforcing ribs, preferably reinforcing ribs oriented radially (46) with respect to the rotation axis (8), are arranged within the base wall (62).

7. The apparatus (40) according to any one of claims 2 to 4, characterized in that the base wall (62) is formed in a concave shape in the region of the support bearing (52) when viewed from the rotation axis (8).

8. The apparatus (40) according to any one of claims 2 to 4, characterized in that the base wall (62) has a bulge (70) directed toward the internal space (64) enclosed by the base wall (62) when viewed from the rotation axis (8) opposite to the support bearing (52).

9. The apparatus (40) according to any one of the prior claims, characterized in that the base (48) has stop walls (80) oriented in the circumferential direction (44) when viewed from the circumferential direction (44) with respect to the rotation axis (8), on the rear side and / or front side.

10. A rotation angle sensor (9) for detecting the rotation angle between a rotor and a stator, comprising the rotor, the stator having a housing and a circuit board (19), and an apparatus (40) according to any one of the prior claims for fixing the rotational position of the housing with respect to a sensor carrier centered on a rotation axis (8), wherein the circuit board (19) is for evaluating an encoder field affected by the rotor.

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