Actuator for a chassis system

Abstract

Actuator (2) for a chassis device, in particular for an actively adjustable roll stabilizer (1) or a steering device of a motor vehicle, comprising: a hollow shaft a drive unit (15, 16) associated with it, wherein the actuator (2) has a shaft-fixed end (5a) and a driven-side end (5b) which can be rotated relative to each other about a rotational axis (3) by means of the drive unit (15, 16) by applying a torque (M) acting between the ends (5a, 5b) of the actuator (2), and A sensor device (10) for detecting the transmitted torque (M) using inverse magnetostriction, wherein the sensor device (10) comprises a primary sensor formed at least partially by the hollow shaft and a sensor unit (11) arranged within the hollow shaft, characterized in that the sensor unit (11) has a sensor housing (23) which contacts the hollow shaft internally and accommodates a coil arrangement (12, 13), wherein the hollow shaft is part of an actuator housing (4) accommodating the drive unit (15, 16), wherein the sensor unit (11) is arranged within the actuator housing (4) which serves at least partially as a primary sensor, and wherein several contact areas (27) are formed on the radially outwardly facing underside of the sensor housing (23), wherein the sensor housing (23) and the actuator housing (4) contact each other exclusively in these contact areas (27).

Description

[0001] The invention relates to an actuator for a chassis device, in particular for an actively adjustable roll stabilizer or a steering device of a motor vehicle, according to the preamble of claim 1, and to an actively adjustable roll stabilizer for a motor vehicle according to claim 15.

[0002] In automotive engineering, particularly chassis engineering, it is known to equip vehicles with a so-called roll stabilizer. In its simplest form, this is essentially a C-shaped torsion bar spring, which is rotatably mounted in its central section relative to the vehicle body, and whose outer, opposing ends are each connected to a wheel suspension. This design ensures that, when cornering, the vehicle body not only compresses on the outside side (due to centrifugal force), but also slightly lowers the inside wheel (resulting in a more stable, less prone position).

[0003] To further enhance ride comfort and vehicle stability, it is known to design roll stabilizers with active adjustability. In this case, the roll stabilizer comprises an actuator and is divided into two stabilizer sections that can be rotated relative to each other about a rotational axis by means of the actuator. By rotating the stabilizer sections relative to each other, a roll movement of the vehicle body is deliberately generated, or a roll movement of the vehicle body caused by external influences is deliberately counteracted. For demand-based control of the actuator, it can be advantageous to detect a torque acting between the stabilizer sections, particularly to incorporate this into a control loop of the actuator.

[0004] It can also be useful to detect the torque acting on the actuator for other actuators used in chassis technology, such as those in the steering system of a motor vehicle.

[0005] From DE 10 2011 078 819 A1, an actively adjustable roll stabilizer for a motor vehicle is known, in which an actuator for rotating the stabilizer sections is arranged between the two stabilizer sections. The roll stabilizer has a sensor device operating on the principle of inverse magnetostriction for detecting a torque acting between the stabilizer sections. For this purpose, a magnetically coded primary sensor is arranged on one stabilizer section, with a magnetic field sensor being provided as a secondary sensor that converts changes in the magnetic field of the primary sensor into an electrical signal. The magnetically coded primary sensor is formed by a section of the stabilizer part. A disadvantage of this is that a magnetic code must be incorporated into the stabilizer section.During operation (of the vehicle), the magnetic coding is exposed to external influences (e.g., mechanical influences such as stone impacts, vibration, or the like, and / or thermal influences), which may impair or at least degrade the functionality of the sensor device. According to a [document / reference]... Fig. In the case shown in DE 10 2011 078 819 A1, the secondary sensor is arranged radially inside a sleeve forming the primary sensor, which in turn is bonded to the inside of a stabilizer section.

[0006] From DE 10 2020 203 136 A1, an actuator for a chassis device according to the features of the preamble of claim 1 is known. The actuator also has a sensor unit whose sensor housing contacts the hollow shaft of the actuator at an inner wall section. The inclusion of a coil arrangement in the sensor housing is not disclosed.

[0007] From DE 10 2017 109 114 A1, a force sensor for measuring axial forces is generally known, which operates, for example, according to the magnetostrictive principle. According to a [document / reference] therein Fig. In the embodiment shown in Figure 1, the sensor has a housing made of soft magnetic material, which serves for shielding and to form a magnetic ring closure. Generator and sensor coils are located inside the housing.

[0008] It is an object of the present invention to provide an actuator for a chassis system, in particular for an actively adjustable roll stabilizer or a steering system of a motor vehicle, whose torque can be reliably and accurately detected, whose sensor device is exposed to external influences to the least possible extent, and which is easy to manufacture. Accordingly, an actively adjustable roll stabilizer for a motor vehicle is to be specified.

[0009] The problem is initially solved by an actuator for a chassis system with the features of claim 1. According to the invention, this actuator comprises: a hollow shaft, a drive unit connected thereto, wherein the actuator has a shaft-fixed end and an output-side end which can be rotated relative to each other about an axis of rotation by means of the drive unit by applying a torque acting between the ends of the actuator, and a sensor device for detecting the transmitted torque using inverse magnetostriction. According to the invention, the sensor device comprises a primary sensor formed at least partially by the hollow shaft and a sensor unit arranged within the hollow shaft.In particular, the primary sensor formed by the hollow shaft serves as a so-called "Hookean deformation body" [linear behavior with respect to the applied force (mechanical stress) and the resulting deformation (mechanical strain)], which, by utilizing an inverse magnetostrictive effect, especially the so-called inverse Villari effect ("length magnetostriction"), transforms the mechanical torque load into a measurable change in its magnetic properties. The sensor unit, in turn, serves primarily as a so-called secondary sensor, whose magnetically acting coupling electronics, on the one hand, dynamically excite the hollow shaft with a magnetic field, and on the other hand, measure the magnetic response of the hollow shaft—especially along two axes diagonal to the axis of symmetry of the hollow shaft.

[0010] According to the invention, the actuator is characterized in that the sensor unit has a sensor housing which makes internal contact with the hollow shaft and accommodates a coil arrangement, wherein the hollow shaft is part of an actuator housing that accommodates the drive unit, wherein the sensor unit is arranged within the actuator housing, which serves at least partially as a primary sensor, and wherein several contact areas are formed on the radially outwardly projecting underside of the sensor housing, the sensor housing and actuator housing contacting each other exclusively in these contact areas. The sensor housing thus has, in particular, the function of holding the coil arrangement required for magnetic excitation and for measuring the magnetic responses in a defined relative position to the hollow shaft serving as the primary sensor, a position that is as unaffected as possible by operational influences.According to the invention, this is achieved by the sensor housing contacting the hollow shaft on the inside, thereby allowing a structurally simple way to achieve a distance between the hollow shaft and the coil assembly that can be predetermined by the housing design. Since it has been shown that the relative position of the coil assembly with respect to the hollow shaft serving as the primary sensor has a significant influence on the measurement results and their quality, the aforementioned problem is advantageously solved by the structural measure of using a housing to accommodate the coil assembly.

[0011] According to the invention, the hollow shaft of the actuator is part of an actuator housing that accommodates the drive unit, with the sensor unit being arranged within the actuator housing, which at least partially serves as a primary sensor. In other words, in this case, the hollow shaft can at least partially form the actuator housing that accommodates the actuator's drive unit. By arranging the sensor unit within this actuator housing, its protection from external mechanical or thermal influences is ensured. By having part of the actuator housing serve as a primary sensor, functional integration is advantageously achieved.

[0012] Advantageously, the shaft-fixed end and the output-side end of the actuator can each be connected to opposite stabilizer sections of the roll stabilizer in order to be able to rotate them against each other around the axis of rotation by means of the drive unit.

[0013] The actuator's drive unit can be an electric motor, which can also be connected to a gearbox, in particular a multi-stage planetary gearbox, to form a drive unit.

[0014] The coil arrangement used according to the invention can be designed in various ways. Advantageously, it comprises a transmitter coil for magnetizing the primary sensor and one, preferably several, receiver coils for detecting the magnetic field of the magnetized primary sensor. By arranging the coils together, an easy-to-handle and simple-to-assemble unit can advantageously be created.

[0015] To ensure that the relative position of the coil arrangement is maintained with respect to the hollow shaft and to protect the coil board, the sensor housing preferably has a trough-shaped base form, which has a curvature on its radially outwardly facing underside adapted to the contour of the hollow shaft, in particular the inner wall of the actuator housing.

[0016] According to the invention, several, in particular four, contact areas are formed on the radially outwardly facing underside of the sensor housing, wherein the sensor housing and actuator housing contact exclusively in these contact areas. This measure advantageously ensures that the sensor housing can be positioned in a defined relative position to the hollow shaft and that this relative position is free from subsequent operational influences such as deformations and / or thermal changes of adjacent components.

[0017] Advantageously, the contact areas protrude radially from the contour of the underside of the sensor housing. This ensures that contact only occurs in these areas.

[0018] Furthermore, it is advantageous for the sensor housing to be manufactured as a molded part, in particular as a plastic molded part.

[0019] Advantageously, the sensor housing has a receiving area for the coil assembly, particularly near the curved underside.

[0020] From a design perspective, this can be advantageously achieved by designing the receiving area to accommodate a coil board, in particular a flat coil board and / or a coil carrier board, which receives the coil arrangement.

[0021] Preferably, the transmitter coil and several receiver coils are arranged on the coil board, in particular side by side.

[0022] The coil board and coil carrier board are preferably connected to each other.

[0023] To ensure a secure and defined mounting, a contour, preferably in the form of several, in particular four, passages, is preferably formed on one of the circuit boards, preferably on the coil carrier board, which is complementary to structural elements formed on the sensor housing in order to hold the coil carrier board against the sensor housing by mutual engagement.

[0024] According to a preferred embodiment of the actuator, two recesses parallel to the axial direction are formed in the sensor housing, into which the coil board projects, at least partially. This ensures that the coil board, which expediently has a substantially planar extent, can be positioned close to the hollow shaft.

[0025] The sensor housing conveniently also accommodates an electronic circuit board electrically connected to the coil assembly.

[0026] The aforementioned problem is further solved by an actively adjustable roll stabilizer for a motor vehicle according to the features of claim 16. According to the invention, this has an actuator of the type described above, the shaft-fixed end of which is connected to a stabilizer section and the output-side end of which is connected to a stabilizer section.

[0027] The invention is explained in more detail below with reference to the accompanying drawing. Further features and advantageous effects of the invention are also shown therein. The drawing shows: Fig. 1 an actively adjustable roll stabilizer of a motor vehicle, in conjunction with opposing wheel suspensions of the right and left sides of the vehicle in a schematic view, Fig. 2 an actuator of an adjustable roll stabilizer with sensor device for torque detection in simplified schematic representation, Fig. 3 one at a like in Fig. 2. Sensor device used in the actuator shown in the axial section of the actuator in a schematically simplified representation, Fig. 4 a sensor unit of a sensor device in perspective view from radially oblique outside, Fig. 5 the sensor device according to Fig. 4 in perspective sectional view, obliquely from the side, Fig. 6 the sensor unit of the Fig. 4 and Fig. 5, arranged in the actuator housing (hollow shaft) of an actuator in axial section, wherein for the sake of illustration other elements of the actuator have been omitted, Fig. 7 the sensor unit (secondary sensor) arranged in the actuator housing (hollow shaft) in the arrangement state as shown in Fig. 6 in perspective view from a slightly elevated angle, Fig. 8 the sensor unit in an alternative perspective view from radial outside, Fig. 9 the sensor unit in perspective view, viewed obliquely from the side, Fig. 10 The sensor unit in top view.

[0028] To illustrate the field of application of the invention, the following is shown. Fig. Figure 1 shows a simplified schematic, perspective view of an actively adjustable roll stabilizer 1 for a motor vehicle. The adjustable roll stabilizer 1 is part of the chassis of a (not shown) motor vehicle, which is not fully depicted. A left wheel 7a and a right wheel 7b located on the opposite side of the vehicle are each connected to the vehicle body via a wheel suspension 8a and 8b, respectively (simplified representation). The left wheel 7a and its associated wheel suspension 8a, and the right wheel 7b and its associated wheel suspension 8b, are each coupled to an outer end of a corresponding stabilizer section 6a and 6b of the actively adjustable roll stabilizer 1. The two stabilizer sections 6a and 6b are connected to each other at the center of the vehicle via an actuator 2 – simplified representation as an essentially cylindrical body.

[0029] In a manner known per se, the adjustable roll stabilizer 1 is rotatably mounted about a rotational axis 3 relative to the vehicle body (mounting not shown in detail). The actuator 2, simplified as a cylindrical body, essentially comprises an actuator housing 4 that is substantially rotationally symmetrical with respect to the rotational axis 3 and which is designed, at least in part, as a hollow shaft and acts accordingly.

[0030] The actuator housing 4 contains, among other things, an electric motor 15 and a multi-stage planetary gearbox 16; see also the section on Fig. 2 referred, which are like in Fig. Figure 1 shows the actuator 2 used in a schematic side view, with the approximate position of the electric motor 15 and gearbox 16 indicated by arrows. The stabilizer sections 6a and 6b are connected to each other via a portion of the actuator housing 4, the electric motor 15, and the coaxially arranged multi-stage planetary gearbox 16. When the electric motor 15 is stationary, the two stabilizer sections 6a and 6b are rigidly connected to each other via the actuator 2. By rotating the electric motor 15, the stabilizer sections 6a and 6b can be rotated relative to each other about the axis of rotation 3, depending on the direction of rotation. Thus, the adjustable roll stabilizer 1 can be adjusted according to... Fig. 1 adjust in a manner known in itself, thereby making it possible to influence the roll behavior of a motor vehicle equipped with the roll stabilizer 1.

[0031] According to the schematic diagram shown, the stabilizer section 6a is fixed to the housing, i.e., it is rotationally fixed to one end 5a of the actuator housing 4. In contrast, the stabilizer section 6b is connected to the actuator 2 at its output-side end 5b. That is, the stabilizer section 6b is rotatably mounted relative to the actuator housing 4, but at the same time is driven by the gearbox output of the actuator 2. Depending on the operating state of the vehicle equipped with the roll stabilizer 1, a torque M acts between the stabilizer sections 6a and 6b, which is Fig. 1 is designated as a double arrow acting around the axis of rotation 3. The magnitude and direction of the torque M depend on the respective operating condition.

[0032] The in Fig. Actuator 2 shown, which is part of a system like the one in Fig. The adjustable roll stabilizer 1, which can be schematically depicted, is further equipped with a control unit 14. This control unit, like the electric motor 15 and the multi-stage planetary gear 16, is located within the actuator housing 4 in a region of the housing facing the housing-mounted stabilizer section 6a. The control unit 14 includes, among other things, electrical and / or electronic components, including those for controlling and supplying power to the electric motor 15. Furthermore, a sensor device 10 is arranged in this region of the actuator housing 4. This sensor device operates on the principle of active inverse magnetostriction and can detect and measure a torque M acting on the actuator 2 about its axis of rotation.

[0033] In Fig. For the sake of simplicity, the stabilizer sections 6a and 6b are shown in Figure 2 as truncated and simplified stubby sections extending along the axis of rotation 3. The actuator 2 located between these stubby sections connects the stabilizer sections 6a and 6b (see Figure 2). Fig. 1) comprises an electric motor 15 and a multi-stage planetary gearbox 16 arranged coaxially thereto, which together with the control unit 14 are arranged within the actuator housing 4. As already mentioned in connection with Fig. As explained in Figure 1, the stabilizer section 6a is rotationally fixed to the actuator housing 4, while the stabilizer section 6b is rotatably mounted relative to the actuator housing 4 and is rotationally fixed to the output of the multi-stage planetary gear 16, so that it can be rotated relative to the (housing-fixed) stabilizer section 6a by means of the electric motor 15 and the gear 16. The housing-fixed end 5a of the actuator is thus connected to the stabilizer section 6a, while at the output-side end 5b of the actuator, the stabilizer section 6b is rotatably mounted relative to the actuator housing 4 and is in drive connection at least with the multi-stage planetary gear 16 and the electric motor 15. Alternatively or additionally, further or other elements could also be present in the drive train thus formed, for example, a clutch, brake, a spring and / or damping device.

[0034] The sensor assembly 10 of the actuator 2 essentially comprises a primary sensor and a secondary sensor. An axial section of the actuator housing 4, located between the electric motor 15 and the housing-fixed end of the actuator 5a, is made of a magnetizable material. According to the physical effect of inverse magnetostriction, i.e., a change in magnetization due to mechanical stresses, this hollow-shafted section of the actuator housing 4, which transmits the torque M between the stabilizer sections 6a and 6b, can be used as the primary sensor. For this purpose, a sensor unit 11, acting as a so-called secondary sensor, is also arranged within the actuator housing 4, as shown in Fig. 3 shown schematically.

[0035] Based on Fig. 3, which make an axial cut through actuator 2 of the Fig. Figure 2 schematically shows the area of ​​sensor unit 11. The operating principle of the sensor device 10 is explained below: Within the essentially rotationally symmetric actuator housing 4, a sensor unit 11 (secondary sensor) is arranged near the housing wall of the actuator housing 4, specifically radially within a section of the actuator housing 4 (hollow shaft) that serves as the primary sensor. The sensor unit 11 has a convex sensor head facing the inner wall of the actuator housing 4 (hollow shaft), which is equipped with a transmitter coil 12 and several receiver coils 13. By means of the transmitter coil 12 arranged on the sensor unit 11, a region of the actuator housing 4 located near it (a specially treated hollow shaft section of the actuator housing 4) can be actively magnetized. The magnetic response of the primary sensor is detected by means of the receiver coils 13 of the sensor unit 11 (secondary sensor).

[0036] If a torque M is applied to the actuator housing 4, as in Fig. As indicated by the curved double arrow in Figure 3, the mechanical stresses induced in the material of the actuator housing 4 cause the hollow shaft to transform the mechanical torque load (the torque M) into measurable changes in its magnetic properties, according to the principle of inverse magnetostriction. Linearity and accuracy are ensured throughout the hollow shaft's service life through its design and material selection. The change in magnetic properties is detected by the receiver coils 13. Thus, the sensor device 10, through the interaction of the primary and secondary sensors, can detect and measure (determine the direction and magnitude of) the torque M acting on the actuator housing 4 (hollow shaft) of the actuator 2.

[0037] Based on the following Fig. 4 and Fig. Figures 5 and 6 to 10 provide explanations regarding the design of the sensor device 10 using an exemplary embodiment, which is described below in different aspects. Since the figures mentioned refer to the same exemplary embodiment, the following description of the exemplary embodiment applies equally to all of the figures mentioned.

[0038] The Fig. 4, Fig. Figures 5 and 8 to 10 show a sensor unit 11 according to one and the same embodiment in different views, with the sensor unit 11 shown separately in these figures. In contrast, the Fig. 6 and Fig. 7 The sensor unit 11 is installed in a hollow shaft section of the actuator housing 4 (installed state). For illustration and clarity, the following are shown in the Fig. 6 and Fig. Besides the sensor unit 11 and the hollow shaft section of the actuator housing, 4 other components of an actuator have been omitted. It is understood that the one in the Fig. 6 and Fig. 7. Section of the actuator housing shown. 4. Part of a as shown based on Fig. 2 or Fig. 1 may be the actuator of a roll stabilizer shown.

[0039] First, the following will be based on the Fig. 4, Fig. Sections 5 and 6 to 10 describe the sensor unit 11 with regard to its construction. The sensor unit 11 therefore comprises, as its essential elements, a sensor housing 23, a coil board 22, and a coil carrier board 18 (in the sectional view according to...). Fig. 6 and Fig. 78), an electronic circuit board 17, and a cage tab 25. The sensor housing 23 is a trough-shaped plastic part with a radially outwardly curved underside. The curvature of the underside is chosen such that, when installed in the actuator housing 4 (hollow shaft), the sensor housing 23 essentially follows the curvature of the inner wall of the actuator housing 4.

[0040] As in the Fig. 4, Fig. 8 and Fig. As shown in Figure 9, four support pads 27 are formed on the underside of the sensor housing 23, which protrude radially from the curved plane of the underside of the sensor housing 23. In the installed state in the actuator housing 4 (see Figure 9), the sensor housings are located on the underside of the sensor housing 23. Fig. 6 and Fig. 7) The sensor housing 23 contacts the actuator housing 4 exclusively via the four contact pads 27. In this way, it is ensured that the sensor housing 23 assumes a defined relative position to the actuator housing 4 (i.e. the “primary sensor”) that remains unchanged throughout the operating time of the actuator 2.

[0041] On the underside of the sensor housing 23, as for example in Fig. As can be seen in Figure 4, two housing slots 28 are formed. Each of the housing slots 28 extends parallel to the axis of rotation 3 (relative to the installation state in the actuator housing 4), thus orthogonal to the direction of curvature of the underside of the sensor housing 23.

[0042] The sensor housing 23 contains, as is best done in the Fig. 6 and Fig. Figure 7 shows a coil carrier board 18 arranged in the base area. This is a flat, rectangular component that is held in position relative to the sensor housing 23 by four retaining pins 21, each of which protrudes through a hole 20 formed in the coil carrier board 18. Accordingly, the coil carrier board 18 is locked in the plane relative to the sensor housing 23 in four areas.

[0043] On the underside, the coil carrier board 18 rests on the sensor housing 23, at least in its outer areas, as shown in Fig. 6 can be seen, which ensures that the coil carrier board 18 is held at a defined distance from the sensor housing 23 and thus at a defined distance and close to the actuator housing 4.

[0044] Below the coil carrier board 18 is the coil carrier board 22, which is attached to the coil carrier board 18. On the coil carrier board 22 is an arrangement of sensor coils – not visible here – comprising at least one transmitter coil and one receiver coil (see explanation of...). Fig. 3) By attaching the coil board 22 to the coil carrier board 18, the transmitter and receiver coils arranged on the coil board 22 are also in a defined position relative to the actuator housing 4. The relative position of the coil board 22 with respect to the actuator housing 4 is of high importance for the reliability and accuracy of the sensor device 10.

[0045] As in Fig. As can be seen in Figure 4, the coil board 22 protrudes into the two housing slots 28 formed on the sensor housing 23 in opposite areas, so that these - as in Fig. 4 shown - visible from below in sections.

[0046] As in Fig. As shown in Figure 5, a plurality of contact pins 19 are formed on the coil carrier board 18. In the illustrated embodiment, these pins project from the coil carrier board 18 in two parallel rows, orthogonally to each other, towards the electronic circuit board 17 and penetrate it. The contact pins 19 serve to establish electrically necessary contacts between the coil carrier board 18, or the coil board 22 arranged on it, and electronic circuits located on the electronic circuit board 17. The individual pins 19 penetrate the electronic circuit board 17, in particular without forming a rigid mechanical connection to it. This ensures, in particular, a certain degree of mechanical decoupling between the coil board 22 and the electronic circuit board 17.This prevents, for example, changes in the position of the electronic circuit board 17, which may be caused in particular by temperature influences or other disturbances, from affecting the relative position of the coil board 22 with respect to the actuator housing 4, which would lead to a deterioration in the accuracy of the sensor device. The electrical connection between pins 19 and circuits on the electronic circuit board 17 is established in a manner to be explained later.

[0047] As in the Fig. As shown in Figures 4, 6 to 10, a so-called cage tab 25 is also associated with the sensor housing 23. The cage tab 25 contributes significantly to maintaining the sensor housing 23 relative to the actuator housing 4 (hollow shaft) in a defined relative position that remains unchanged, particularly over the service life of the sensor device 10. The cage tab 25 is a metallic molded part that surrounds the sensor housing 23 like a frame. The cage tab exhibits spring properties; in particular, it is resiliently deformable. The cage tab 25 has two parallel brackets 33, 34, each terminating at a front connecting web 35 and a rear connecting web 36, respectively. The front and rear connecting webs 35, 36 also run parallel to each other, perpendicular to the two brackets 33, 34.On the front connecting web 35, an approximately teardrop-shaped soldering surface 26 is formed, which projects forward from the cage tab 25; a corresponding teardrop-shaped soldering surface 26, projecting backward, is formed on the rear bracket. The terms "front" and "rear" in this context refer to the overall extent of the sensor housing 23.

[0048] How the Fig. 4, Fig. 8, Fig. 9 and Fig. As can be seen from Figure 10, the brackets 33, 34 of the cage tab 25 run laterally from the sensor housing 23, while the connecting webs 35, 36 run transversely thereto parallel to the end faces of the sensor housing 23, see in particular Fig. 10.

[0049] As in Fig. As shown in Figure 9, the brackets 33, 34 of the cage tab 25 are each supported in their central areas by a shoulder 31 formed on the sensor housing 23. A radially outward force can be exerted on the sensor housing 23 from the cage tab 25 via the shoulder 31. A radially inward-pointing projection in the form of a retaining arm 32 formed on each shoulder 31 prevents the brackets 33, 34 of the cage tab 25 from slipping laterally outward off the shoulder 31.

[0050] With reference to Fig. Figure 10 shows that a total of eight locating lugs 24 are formed on the sensor housing 23 in the illustrated embodiment. Four of these locating lugs 24 project forward and backward (tangential direction) from the sensor housing 23, while four other locating lugs 24 project laterally (in opposite axial directions) from the sensor housing 23. The sensor housing 23 rests against the cage tab 25 in both the tangential and axial directions exclusively at the contact points defined by the eight locating lugs 24. This ensures that the relative position of the sensor housing 23 with respect to the actuator housing 4 is decoupled as much as possible after assembly from any deformations (thermally or mechanically induced) or other disturbances that could affect the relative position of the sensor housing 23 with respect to the actuator housing 4.Advantageously, the fitting lugs 24 are cut to size and / or rubbed down by the spring action of the cage tab 25 during assembly, so that (at room temperature, which is the same as the assembly temperature) a play-free connection is created.

[0051] To attach the sensor unit 11 to the actuator housing 4, the sensor unit 11, including cage tab 25, is inserted into the actuator housing 4 as shown in the Fig. 6 and Fig. Figure 7 shows the four support pads 27 formed on the underside of the sensor housing 23, ensuring that the coil board 22 in particular assumes a defined relative position to the actuator housing 4.

[0052] To attach the sensor unit 11 to the actuator housing 4, the cage tab 25 is pressed downwards, i.e., radially outwards, in the area of ​​the two protruding soldering surfaces 26 (and thus slightly elastically deformed) and then soldered to the inner wall of the actuator housing 4, thus forming a metallurgical bond. It should be noted that the cage tab 25 can also be metallurgically bonded to the actuator housing 4 in an alternative manner, in particular by welding, preferably by resistance spot welding.

[0053] Due to the previous slight elastic deformation, the cage tab 25, in its deformed state, exerts a restoring force on the shoulders 31 of the sensor housing 23 in the area of ​​the brackets 33, 34, so that the entire sensor housing 23 conforms to the Fig. The force flow from the spring-loaded cage tab 25 to the sensor housing 23 is optimized such that the support pads 27 (contact areas with the actuator housing 4) are each positioned approximately below the pressure exerted by the arrows shown in Figure 9. Fig. The force application points indicated by the 10 force arrows are arranged so that the electronics, coil carrier, and coil board are largely kept out of the force flow. Due to the sensor housing 23 being attached to the actuator housing 4 exclusively via the four support pads 27, a friction-based and force-fit connection is created, thus ensuring a permanent positioning of the sensor housing 23.

[0054] According to the in Fig. As shown in Figure 5, and partly explained previously, the design of the sensor unit 11 largely decouples the electronic circuit board 17 from the coil carrier board 18 and the coil board 22. It should be noted that during operation of the sensor unit 11, the electronic circuit board 17 may heat up and thus expand due to thermal reasons. Other components, such as the housing 23, the pins 19, the coil carrier board 18, the coil board 22, and the cage tab 25, may also heat up (or cool down) during operation. The described design ensures that thermal changes in length, particularly in the plane of the circuit board (electronic circuit board 17), can be compensated for. Therefore, the initial relative position of the coil board 22 with respect to the actuator housing 4, established when the sensor unit 11 is mounted, can remain largely unchanged throughout its operating life.

[0055] As described using the previous figures, and especially in the Fig. 6 and Fig. As shown in Figure 7, the coil carrier board 18, which is connected to the coil carrier board 22 to hold it in a defined relative position to the actuator housing 4, is secured to the sensor housing 23 by four retaining pins 21. The retaining pins 21 each pass through holes 20 formed in the coil carrier board 18. Reference sign 1 roll stabilizer 2 Actuator 3. Rotation axis 4 Actuator housings (hollow shaft) 5a Housing-mounted end of the actuator 5b output-side end of the actuator 6a Stabilizer section (fixed to the housing) 6b Stabilizer section (output side) 7a, 7b Rad 8a, 8b Wheel suspension 10 Sensor setup 11 Sensor unit (secondary sensor) 12 Transmitter coil 13 Receiver coil 14 Control 15 Electric motor 16 (multi-stage planetary) gearboxes 17 Electronic circuit board 18 Coil carrier board 19 Contact pin 20 holes 21 Retaining pin 22 Coil board 23 Sensor housings 24 Passnase 25 cage tabs 26 soldering surfaces 27 support pads 28 case slots 31 Shoulder 32 Support arm 33 irons 34 irons 35 Bridge 36 Bridge M torque

Claims

[1] Actuator (2) for a chassis device, in particular for an actively adjustable roll stabilizer (1) or a steering device of a motor vehicle, comprising: a hollow shaft a drive unit (15, 16) associated with it, wherein the actuator (2) has a shaft-fixed end (5a) and a driven-side end (5b) which can be rotated relative to each other about a rotational axis (3) by means of the drive unit (15, 16) by applying a torque (M) acting between the ends (5a, 5b) of the actuator (2), and a sensor device (10) for detecting the transmitted torque (M) using inverse magnetostriction, wherein the sensor device (10) comprises a primary sensor formed at least partially by the hollow shaft and a sensor unit (11) arranged within the hollow shaft, characterized by, that the sensor unit (11) has a sensor housing (23) which contacts the hollow shaft on the inside and accommodates a coil arrangement (12, 13), wherein the hollow shaft is part of an actuator housing (4) accommodating the drive unit (15, 16), wherein the sensor unit (11) is arranged within the actuator housing (4) which serves at least partially as a primary sensor, and wherein several contact areas (27) are formed on the radially outwardly facing underside of the sensor housing (23), wherein the sensor housing (23) and the actuator housing (4) contact each other exclusively in these contact areas (27). [2] Actuator (2) according to any of the preceding claims, characterized by , that the shaft-fixed end (5a) and the output-side end (5b) can each be connected to opposite stabilizer sections (6a, 6b) of the roll stabilizer (1) in order to rotate them against each other about the axis of rotation (3) by means of the drive unit (15, 16). [3] Actuator (2) according to any of the preceding claims, characterized by , that the coil arrangement (12, 13) comprises a transmitter coil (12) for magnetizing the primary sensor and one, preferably several, receiver coils (13) for detecting the magnetic field of the magnetized primary sensor. [4] Actuator (2) according to any of the preceding claims, characterized by , that the sensor housing (23) has a trough-like basic shape, which has a curvature on its radially outwardly facing underside adapted to the contour of the hollow shaft, in particular the inner wall of the actuator housing (4). [5] Actuator (2) according to any of the preceding claims, characterized by , that four contact areas (27) are formed on the radially outwardly facing underside of the sensor housing (23) for the exclusive contact of sensor housing (23) and actuator housing (4). [6] Actuator (2) according to any of the preceding claims, characterized by, that the installation areas (27) protrude radially from the contour of the underside of the sensor housing (23). [7] Actuator (2) according to any of the preceding claims, characterized by , that the sensor housing (23) is manufactured as a molded part, in particular as a plastic molded part. [8] Actuator (2) according to any of the preceding claims, characterized by , that the sensor housing (23) has a receiving area for the coil arrangement (12, 13) particularly near the curved underside. [9] Actuator (2) according to claim 8, characterized by , that the receiving area is designed to receive a coil board (22) and / or a coil carrier board (18) that receives the coil arrangement (12, 13), in particular a flat coil board. [10] Actuator (2) according to claim 9, characterized by , that the transmitter coil (12) and several receiver coils (13), in particular next to each other, are arranged on the coil board (22). [11] Actuator (2) according to claim 9 or 10, characterized by , that the coil board (22) is connected to the coil carrier board (18). [12] Actuator (2) according to any one of claims 9 to 11, characterized by , that on one of the circuit boards, preferably on the coil carrier board (18), a contour, preferably in the form of several, in particular four, passages (20) is formed which is complementary to structural elements (21) formed on the sensor housing (23) in order to hold the coil carrier board (18) relative to the sensor housing (23) by mutual engagement. [13] Actuator (2) according to any of the preceding claims, characterized by , that two recesses (28) running parallel to the axial direction are formed on the sensor housing (23), into which the coil board (22) protrudes at least partially. [14] Actuator (2) according to any of the preceding claims, characterized by, that the sensor housing (23) continues to accommodate an electronic circuit board (17) electrically connected to the coil arrangement (12, 13). [15] Actively adjustable roll stabilizer (1) for a motor vehicle, comprising an actuator (2) according to one of the preceding claims, the shaft-fixed end (5a) of which is connected to a stabilizer section (6a) and the output-side end (5b) of which is connected to a stabilizer section (6b).

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