EP3448741A1

EP3448741A1 - Motor vehicle steering assembly

Info

Publication number: EP3448741A1
Application number: EP17718367.0A
Authority: EP
Inventors: Stefan Jaekel; Robert Engler
Original assignee: TRW Automotive GmbH
Current assignee: ZF Automotive Germany GmbH
Priority date: 2016-04-28
Filing date: 2017-04-19
Publication date: 2019-03-06
Also published as: DE102016107916A1; CN109070937A; US20190118861A1; WO2017186546A1

Abstract

The invention relates to a motor vehicle steering assembly (10) comprising a steering shaft (12) which extends from a vehicle steering wheel (14) to a pinion (16) and which can be rotated about a steering axis (A), a combination steering angle and steering torque sensor (18) which has sensor elements (31, 35) that are rotationally fixed to the steering shaft (12), and a housing upper part (20) of a multipart steering transmission housing (22), wherein the housing upper part closes a housing lower part (24) for receiving the pinion (16) on the steering wheel side, said housing lower part being open in the axial direction towards the vehicle steering wheel (14). The combination steering angle and steering torque sensor (18) is received in the housing upper part (20), and the steering shaft (12) extends through the housing upper part (20). The sensor elements (31, 35) which are rotationally fixed to the steering shaft (12) directly adjoin the housing upper part (20).

Description

Motor vehicle steering assembly

The invention relates to a motor vehicle steering assembly having a steering shaft which extends from a vehicle steering wheel to a pinion and is rotatable about a steering axis, a combined steering angle and steering torque sensor having non-rotatably connected to the steering shaft sensor elements, a housing upper part of a multi-part steering gear housing, which closes in the axial direction of the steering wheel towards open housing lower part for receiving the pinion steering wheel side, wherein the combined steering angle and steering torque sensor is received in the housing upper part, and wherein the steering shaft extends through the housing upper part. Such motor vehicle steering assemblies are already generally known from the prior art and are used in rack and pinion steering, in which both the steering angle and the manually applied steering torque to be detected by sensors. The sensors are usually floating to compensate for radial and axial tolerances caused by the movement of the steering shaft.

Combined steering angle and steering torque sensors require compared to sensors that detect only the steering angle or only the steering torque, a larger space, so that their integration into the motor vehicle steering due to the tight space conditions in the steering shaft made difficult.

It is therefore an object of the invention to provide a compact motor vehicle steering assembly with a combined steering angle and steering torque sensor.

According to the invention this object is achieved by a motor vehicle steering assembly of the type mentioned, in which the non-rotatably connected to the steering shaft sensor elements directly adjacent to the housing upper part of the multi-part steering gear housing. While conventional combined steering angle and steering torque sensors are manufactured as a prefabricated sensor unit with a separate sensor housing and then installed in the steering gear housing, according to the invention, no separate housing is provided radially between the housing upper part of the steering gear housing and the rotatable sensor elements, comprising the rotatable and stationary sensor elements wrapped and after the sensor mounting in the radial direction against rotation is connected to the steering gear housing. However, the immediately adjacent to the housing upper part, firmly connected to the steering shaft sensor elements (for example, by a radial air gap) may be spaced from the housing upper part.

The function of the sensor housing is taken from the housing upper part of the steering gear housing, so that a separate sensor housing omitted and the motor vehicle steering assembly can be made correspondingly compact. The compared to a pure steering angle sensor or a pure steering torque sensor increased space requirement of the combined steering angle and steering torque sensor is approximately compensated by the elimination of the separate sensor housing, so that through the use of the combined steering angle and steering torque sensor less space problems arise in the steering shaft.

In one embodiment of the automotive steering assembly, the steering shaft includes an input shaft connected to the vehicle steering wheel, an output shaft connected to the pinion, and a torsion member that circumferentially couples the input shaft and the output shaft. Thus can be determined from a rotation of the input shaft relative to the output shaft and the torsional resistance of the torsion element in a simple manner, the steering torque applied to the steering wheel.

The combined rotational angle and torque sensor preferably comprises a first sensor element which has a rotationally fixed connection to the input shaft, and a second sensor element which has a rotationally fixed connection to the output shaft, wherein at least one of the rotationally fixed connections is formed as an axial plug connection. Compared with currently common welds, the non-rotatable mounting of a sensor element on the Input shaft or output shaft realize much faster and easier by an axial connector.

In this case, the first sensor element or the input shaft preferably has an integrated or permanently pre-assembled form-locking ring for forming the rotationally fixed connection.

Furthermore, it is preferred that the second sensor element or the output shaft has an integrated or permanently pre-assembled form-locking ring for forming the rotationally fixed connection. In particular, it is conceivable in this connection to realize the axial plug connection for the rotationally fixed mounting of a sensor element on the input shaft or output shaft via interlocking toothings.

Alternatively, at least one of the sensor elements may have radially elastic plug connection tongues, which in each case engage on a tangentially flattened circumferential section of the input shaft and / or the output shaft for forming the axial plug connection.

In one embodiment of the motor vehicle steering assembly, the housing upper part comprises a flange section, which surrounds the sensor elements fixedly connected to the steering shaft and is connected to the housing lower part of the multi-part steering gear housing. Furthermore, the housing upper part preferably comprises a bearing portion, which has a radial bearing for rotatably supporting the steering shaft and supporting transverse forces.

In particular, a sealing element for sealing between the housing upper part and the steering shaft can be arranged in this bearing section. With the envelope of the combined steering angle and steering torque sensor, the provision of a rotary bearing for the steering shaft and the seal of the steering gear housing to the steering shaft toward the housing upper part takes over several functions, thus contributing to a particularly compact design of the motor vehicle steering assembly. According to one embodiment of the motor vehicle steering assembly, the flange portion and the bearing portion form separate components of the housing top.

In this embodiment, it is preferred that the flange portion of the housing upper part surrounds the combined steering angle and steering torque sensor and is arranged axially between the bearing portion of the housing upper part and the housing lower part.

Further, in this embodiment, the combined steering angle and steering torque sensor may include a magnetic ring, a magnetic ring rotatable relative to the magnetic ring, and an electrical sensor unit, wherein the flange portion, the magnetic assembly, and the electrical sensor unit form a preassembled subassembly. For example, this subassembly may be preassembled by a supplier and then allows rapid assembly of the automotive steering assembly. According to an alternative embodiment of the motor vehicle steering assembly, the flange portion and the bearing portion of the housing upper part are formed integrally. In this case, the number of individual components and thus also the assembly costs for the motor vehicle steering assembly are reduced. For example, in this embodiment of the automotive steering assembly, the combined steering angle and steering torque sensor includes a magnetic ring, a magnetic ring rotatable relative to the magnetic ring, and an electrical sensor unit, wherein the housing upper, the magnetic assembly, and the electrical sensor unit form a preassembled subassembly. For example, this subassembly may be preassembled by a supplier and then allows rapid assembly of the automotive steering assembly.

Alternatively, in this embodiment of the automotive steering assembly, the housing upper and the combined steering angle and steering torque sensors may also constitute a preassembled subassembly. For example, this subassembly can be pre-assembled by a supplier and tested for its correct sensor status even before it is installed in the vehicle steering assembly. check the function. Furthermore, this subassembly allows a particularly simple assembly of the motor vehicle steering assembly because it is merely axially attached to the steering shaft and then connected to the lower housing part of the multi-part steering gear housing. According to a further embodiment of the motor vehicle steering assembly, the combined steering angle and steering torque sensor comprises a magnet ring, a magnetic assembly and an electrical sensor unit, wherein the magnetic assembly has a gear rim arranged coaxially with the steering shaft and fixedly connected to the steering shaft, and wherein the electrical sensor unit at least one elastic has stored gear which is in mesh with the gear rim. In particular, the gear of the electrical sensor unit is elastically mounted in the radial direction, so that a correct sensor function is ensured even if the steering shaft has certain manufacturing tolerances, such as a slight bend and / or a radial offset between the input shaft and the output shaft, or if an offset By dynamic movement of the steering shaft to the steering gear housing by Kardankräfte arises.

Further features and advantages of the invention will become apparent from the following description of preferred embodiments with reference to the drawings. In these show:

1 shows a longitudinal section through a motor vehicle steering assembly according to the invention according to an embodiment in the installed state;

FIG. 2 shows an assembly method for the motor vehicle steering assembly according to FIG. 1; FIG. 3 is a simplified exploded perspective view of a combined steering angle and steering torque sensor of the motor vehicle steering assembly according to FIG. 1;

4 shows a longitudinal section through a motor vehicle steering assembly according to the invention according to a further embodiment in the installed state; 5 shows a longitudinal section through a motor vehicle steering assembly according to the invention according to a further embodiment in the installed state;

FIG. 6 shows the motor vehicle steering assembly according to FIG. 5 disassembled into subassemblies;

FIG. 7 shows a perspective view of the motor vehicle steering assembly according to FIG. 6 in the assembled state;

8 shows a longitudinal section through a motor vehicle steering assembly according to the invention according to a further embodiment in the installed state;

FIG. 9 shows the motor vehicle steering assembly according to FIG. 8 disassembled into subassemblies;

Figure 10 is a perspective view of the motor vehicle steering assembly according to Figure 9 in the assembled state; - Figure 1 1 is a longitudinal section through a motor vehicle steering assembly according to the invention according to another embodiment in the installed state;

FIG. 12 shows the motor vehicle steering assembly according to FIG. 1, disassembled into subassemblies; FIG. 13 shows a perspective view of the motor vehicle steering assembly according to FIG. 12 in the assembled state,

FIG. 14 shows a rotational drive between a magnetic ring and a magnetic structural unit of the motor vehicle steering assembly according to FIGS. 11 to 13; FIG. 15 shows a detailed view of the rotationally fixed connection between the output shaft and a form-locking ring attached to the second sensor element;

FIG. 16 shows a detailed view of the connection illustrated in FIG. 15 according to an alternative embodiment variant, 17 shows a detailed view of the connection shown in FIG. 15 according to a further alternative embodiment variant,

FIG. 18 shows a detailed view of the connection illustrated in FIG. 15 according to a further alternative embodiment variant, FIG. 19 shows a detailed view of the connection illustrated in FIG. 15 according to a further alternative embodiment variant,

FIG. 20 shows a detailed view of the connection illustrated in FIG. 15 according to a further alternative embodiment variant,

FIG. 21 shows a detail view of the connection illustrated in FIG. 15 according to a further alternative embodiment, and

FIG. 22 shows a detailed view of a form-locking ring fastened to the output shaft for the rotationally fixed connection to the second sensor element.

1 shows an embodiment of a motor vehicle steering assembly 10 for rack and pinion steering of motor vehicles, with a steering shaft 12 which extends from a schematically indicated vehicle steering wheel 14 to a pinion 16 and is rotatable about a steering axis A, a combined steering angle and steering torque sensor 18, the rotatably connected to the steering shaft 12 connected sensor elements 31, 35, and a housing upper part 20 of a multi-part steering gear housing 22, wherein the combined steering angle and steering torque sensor 18 is housed in the housing upper part 20.

The multi-part, designed as an outer housing steering gear housing 22 comprises according to Figure 1, apart from the housing upper part 20 in the axial direction of the vehicle steering wheel 14 toward open housing base 24 for receiving the pinion 16, wherein the housing upper part 20 closes the housing base 24 on the steering wheel side ,

The steering shaft 12 extends through the multi-part steering gear housing 22, in particular by the housing upper part 20, the steering shaft 12 projecting from the steering wheel side of the housing upper part 20 axially and is sealed to the housing upper part 20. According to Figure 1, the steering shaft 12 comprises a rotatably connected to the vehicle steering wheel 14 connected input shaft 26, a rotatably connected to the pinion 16 output shaft 28 and a Torsionsstab designed as a torsion element 30 which couples the input shaft 26 and the output shaft 28 in the circumferential direction. Further, the torsion bar in the axial direction with the input shaft 26 and the output shaft 28 is fixedly connected, in particular pressed.

A rotation of the vehicle steering wheel 14 coupled in a rotationally fixed manner to the input shaft 26 is consequently transmitted to the output shaft 28 via the torsion element 30. The pinion 16 of the output shaft 28 meshes in a known manner with a rack of motor vehicle steering, which in turn is coupled with steerable vehicle wheels and transmits a rotation of the vehicle steering wheel 14 in a steering angle of the steerable vehicle wheels.

The combined steering angle and steering torque sensor 18 is provided to detect both a steering angle of the steering shaft 12 and a steering torque applied to the vehicle steering wheel 14. For this purpose, the combined steering angle and steering torque sensor 18 rotationally fixed to the steering shaft 12 connected sensor elements. In particular, a first sensor element 31, such as a gear rim 32 with magnetizable metal rings 34 (see also FIG. 3), is non-rotatably coupled to the input shaft 26, while a second sensor element 35, such as a magnetic ring 36 designed as a magnet wheel, is non-rotatably coupled to the output shaft 28 (see Figure 2).

The non-rotatably connected to the steering shaft 12, concretely connected to the input shaft 26 or the output shaft 28 sensor elements 31, 35 in the radial direction directly adjacent to a peripheral wall of the housing upper part 20, wherein between the sensor elements 31, 35 and the housing upper part 20 a Circumferentially circumferential, radial air gap is provided. The function of a sensor housing is thus taken over by the housing upper part 20 of the steering gear housing 22, so that no separate intermediate housing is provided between the housing upper part 20 and the rotatable sensor elements 31, 35. The omission of such a separate intermediate housing results in a particularly compact motor vehicle steering assembly 10, since the space requirement is reduced both in the axial direction and in the radial direction.

The housing upper part 20 comprises a flange section 38, which surrounds the sensor elements 31, 35 firmly connected to the steering shaft 12 and is connected to the housing lower part 24, in particular a flange section 40 of the housing lower part 24. Further, in the housing upper part 20, in particular in the flange portion 38 of the housing upper part 20, a connection shaft 58 is provided, via which the combined steering angle and steering torque sensor 18 is connected to an electrical control unit of the motor vehicle steering. In addition, via the connection shaft 58, an electrical sensor unit 50 of the combined steering angle and steering torque sensor 18 can be inserted into the housing upper part 20 (see FIG. 2, right).

Further, the housing upper part 20 comprises a bearing portion 42 which has a radial bearing 44 for rotatably supporting the steering shaft 12, wherein the radial bearing 44 concretely forms a pivot bearing for the input shaft 26.

According to FIG. 1, moreover, a sealing element 46 for sealing between the housing upper part 20 and the steering shaft 12 (specifically, the input shaft 26) is also arranged in the bearing section 42 of the housing upper part 20.

In the embodiment of the motor vehicle steering assembly 10 according to FIG. 1, the flange section 38 and the bearing section 42 of the housing upper part 20 are formed in one piece. The housing upper part 20 is preferably made of a plastic, but alternatively, a metal version would be conceivable.

In any case, the housing upper part 20 must be designed to be sufficiently stable in order to absorb 30 axial withdrawal forces and radial forces of the input shaft 26 at a fraction of the torsion element.

FIG. 2 illustrates an assembly method of the motor vehicle steering assembly 10 according to FIG. 1.

In this case, the housing upper part 20 is initially provided, which comprises the flange section 38 and the bearing section 42 formed integrally with the flange section 38. The sealing element 46 and the radial bearing 44 are then inserted into the housing upper part 20 and secured in the region of the bearing portion 42 on the housing upper part 20, so that a preassembled subassembly arises.

The combined steering angle and steering torque sensor 18 includes in the illustrated embodiment of the motor vehicle steering assembly 10 as a first sensor element 31, a magnetic assembly 48 (see also FIG. 3), as a second sensor element 35 the magnetic ring 36 and, moreover, a fixed housing upper part 20 connected, electrical sensor unit 50th

The magnetic assembly 48 has centrally an axial recess for the passage of the input shaft 26 and is axially inserted onto the input shaft 26 and rotatably connected to the input shaft 26. In the illustrated embodiment, the magnetic assembly 48 has a steering wheel side axially projecting metal sleeve 51 which is welded to the input shaft 26 to secure the magnetic assembly 48 to the steering shaft 12. Alternatively, the non-rotatable connection can also be realized by a form-locking connection during axial attachment of the magnetic assembly 48, whereby the assembly effort for the motor vehicle steering assembly 10 is significantly reduced. A positive connection formed by attaching the magnetic assembly 48 axially can be produced analogously to the embodiment variants shown in FIGS. 15 to 22.

The magnetic ring 36 is formed in a known manner as a pole and has a plurality of permanent magnets whose poles are arranged alternately in the circumferential direction. The magnetic ring 36 also has a central axial recess for the passage of the output shaft 28 is placed on the output shaft 28 and rotatably connected thereto. In the illustrated embodiment, the metal ring magnet 36 on the pinion side an axially projecting, sleeve-shaped projection 53, which is welded to the output shaft 28 in order to secure the magnet ring 36 to the steering shaft 12. Alternatively, the rotationally fixed connection can also be realized by a form-locking connection during axial attachment of the magnetic ring 36, whereby the assembly effort for the motor vehicle steering assembly 10 is significantly reduced. Possible embodiments for a positive connection produced by attaching the magnetic ring 36 axially are shown in FIGS. 15 to 22. According to Figures 1 and 2, a transport protection element 52 is further provided, which closes the pinion side open housing upper part 20 before mounting the motor vehicle steering assembly 10 on the housing base 24. Together with the radial bearing 44 prevents the transport protection element 52 undesirable vibration of the input shaft 26 in the housing upper part 20, which could lead to damage of the combined steering angle and steering torque sensor 18.

In the embodiment according to Figure 1, the transport protection element 52 is formed as a plastic ring 54 which is plugged onto the output shaft 28 and after mounting the housing upper part 20, the output shaft 28 radially fixed in the middle in the housing upper part 20 (see detail in Figure 1). The plastic ring 54 can serve only temporarily as a transport protection for the motor vehicle steering assembly 10 and before assembly of the motor vehicle steering assembly 10 on the housing lower part 24 of the steering gear housing 22 are removed again. Alternatively, however, it is also conceivable that the plastic ring 54 remains permanently in the steering gear housing 22.

After the rotationally fixed mounting of the magnetic assembly 48 to the input shaft 26, the housing upper part 20 is pushed with the pre-mounted radial bearing 44 and sealing member 46 from the steering wheel end of the steering shaft 12 axially over the magnetic assembly 48 and fixed.

For axial fixation of the housing upper part 20 on the steering shaft 12, a snap ring 56 is provided, for example, which is inserted axially onto the input shaft 26 after assembly of the housing upper part 20 and locked in an input shaft groove, so that it moves the housing upper part 20th relative to the steering shaft 12 axially to the vehicle steering wheel 14 toward prevented.

In the next assembly step, the electrical sensor unit 50 is inserted radially into the connection shaft 58 of the housing upper part 20 (see FIG. 2, right) until the electrical sensor unit 50 has reached a desired final assembly position relative to the magnetic assembly 48. Alternatively, it is also conceivable that an assembly of the electrical sensor unit 50 takes place only after the assembly of the other components of the motor vehicle steering assembly 10 and their installation in a vehicle steering. The electrical sensor unit 50 includes, for example, a printed circuit board 59 with Hall sensors 60, small gears 61 for steering angle measurement (see also FIG. 3), a closure element 62 which substantially seals the connection shaft 58, and a plug connector 64 for connecting the combined steering angle measurement. and steering torque sensor 18 to a power supply and an electrical control unit of the vehicle steering.

After the electrical sensor unit 50 is sealed in the connection shaft 58 of the housing upper part 20, the magnetic ring 36 is aligned in the circumferential direction on the magnetic assembly 48 and rotatably connected to the output shaft 28.

If a desired mounting position of the magnet ring 36 can be determined beforehand in the circumferential direction, according to an alternative embodiment, it is also conceivable for the magnet ring 36 to be fixed against rotation at the beginning of the assembly process, ie before assembly of the magnetic assembly 48 and the housing upper part 20 the output shaft 28 to connect.

The assembly of the motor vehicle steering assembly 10 is then completed with the attachment of the transport protection element 52 to the output shaft 28. It is now possible, for example, a function check of the combined steering angle and steering torque sensor 18 and a transport to the other components of the rack and pinion steering to install the motor vehicle steering assembly 10. This installation can be realized quickly and easily by a tight attachment of the housing upper part 20 on the housing lower part 24 of the multi-part steering gear housing 22. Specifically, this attachment can be performed, for example, as a clamping connection, latching connection or screw connection, wherein for sealing between the housing upper part 20 and the housing lower part 24, in particular a seal 65 is provided (see, for example, Figure 1).

3 shows a simplified view of the essential structure of the magnetic assembly 48 and the electrical sensor unit 50 of the combined steering angle and steering torque sensor 18th

It is clear that the magnetic assembly 48 as the main components of the example made of plastic gear rim 32 with an external toothing 66 and two magnetizable metal rings 34 having axially projecting and interlocking metal tongues 68.

Between the metal rings 34 of the magnetic assembly 48 and the magnetic ring 36 is formed a magnetic field which changes in a relative rotation between the input shaft 26 and the output shaft 28.

This magnetic field change is detected in a known manner by Hall sensors 60 in the electrical sensor unit 50 and passed on to an electrical control unit. Together with the torsional resistance of the torsion element 30, the electrical control unit can determine therefrom in a known manner a steering torque applied to the vehicle steering wheel 14.

According to FIG. 3, the electrical sensor unit 50 also has two toothed wheels 61, which mesh with the ring gear 32 of the magnetic assembly 48 in meshing engagement. To be able to compensate for any manufacturing tolerances of the steering shaft 12 such as a certain bend or a radial offset between the input shaft 26 and output shaft 28, the gears 61 are elastically supported with respect to the steering axis A in particular in the radial direction. By this simple compensation of manufacturing tolerances, the reliability of the combined steering angle and steering torque sensor 18 is increased. Upon a rotation of the vehicle steering wheel 14, the magnetic assembly 48, which is connected in a rotationally fixed manner to the input shaft 26, and thus the gear rim 32, is rotated. The gears 61 of the electrical sensor unit 50 mesh with an external toothing 66 of the gear rim 32 and are accordingly also rotated. Furthermore, the gears 61 are coupled to dipoles, so that one of the Hall sensors 60 of the electrical sensor unit 50 can detect the rotation of the gears 61 in a known manner and transmit corresponding data to the electrical control unit of the vehicle steering system in order to determine the steering angle.

FIG. 4 shows the motor vehicle steering assembly 10 according to an alternative embodiment, which differs from the motor vehicle steering assembly 10 according to FIG. 1 only in that the transport protection element 52 is not designed as a plastic ring 54 but as a bearing 70. Figures 5 to 7 show the motor vehicle steering assembly 10 according to another embodiment.

The general structural design as well as the operating principle of the combined steering angle and steering torque sensor 18 remain essentially unchanged with respect to the embodiment described with reference to FIGS. 1 to 3, so that reference is made in this regard to the above description and will be discussed below for differences.

The motor vehicle steering assembly 10 according to FIGS. 5 to 7 differs essentially from the embodiment according to FIGS. 1 to 5 in that the flange section 38 and the bearing section 42 of the housing upper part 20 are no longer made in one piece, but separate components of the housing upper part 20 form.

The flange portion 38 of the housing upper part 20 surrounds the combined steering angle and steering torque sensor 18 and is arranged axially between the bearing portion 42 of the housing upper part 20 and the housing lower part 24 of the steering gear housing 22.

Analogous to the embodiment according to FIGS. 1 to 3, the combined steering angle and steering torque sensor 18 comprises the magnetic ring 36, the magnetic assembly 48 rotatable relative to the magnetic ring 36, and the housing-mounted electrical sensor unit 50, wherein the flange portion 38, the magnetic assembly 48 and the electrical Sensor unit 50 in the embodiment according to Figures 5 to 7 form a preassembled subassembly 72.

The flange portion 38 encloses in the axial direction substantially the entire magnetic assembly 48. Only the metal sleeve 51 of the magnetic assembly 48 protrudes axially slightly beyond the flange portion 38 in order to easily weld the magnetic assembly 48 with the input shaft 26 can.

When assembling the motor vehicle steering assembly 10 according to FIGS. 5 to 7, the preassembled subassembly 72 of flange section 38, magnetic assembly 48 and electrical sensor unit 50 is first pushed onto the input shaft 26 and fixedly connected, in particular welded, to the input shaft 26. Thereafter, a seal 74 and the Lagerab- section 42 with the pre-assembled radial bearing 44 and the pre-assembled sealing element 46 axially pushed onto the input shaft 26 to seal the flange 38 side of the steering wheel sealing.

In the final step of assembly of the automotive steering assembly 10, the magnet ring 36 is circumferentially adjusted on the output shaft and fixedly connected to the output shaft 28. In particular, the magnetic ring 36 is welded analogously to the embodiment according to Figures 1 to 3 via its axial sleeve-shaped extension 53 with the output shaft 28.

FIG. 5 shows a longitudinal section through the motor vehicle steering assembly 10 already installed in the rack-and-pinion steering system, wherein the flange section 38 of the housing upper part 20, the bearing section 42 of the housing upper part 20 and the flange section 40 of the housing lower part 24 are connected to one another by screws 76 are.

Of course, alternative mounting options are conceivable instead of the screw connection, which allow a tight connection of the individual components of the multi-part steering gear housing 22.

FIGS. 8 to 10 show the motor vehicle steering assembly 10 according to a further embodiment.

The motor vehicle steering assembly 10 according to FIGS. 8 to 10 differs from the embodiment according to FIGS. 5 to 7 only in that the flange section 38 and the bearing section 42 of the housing upper part 20 are formed in one piece.

Also in this embodiment, the combined steering angle and steering torque sensor 18 comprises the magnetic ring 36, the magnetic ring 48 rotatable relative to the magnetic ring 36 and the housing-mounted electrical sensor unit 50, wherein the one-piece housing top 20, the magnetic assembly 48 and the electrical sensor unit 50th form a preassembled subassembly 77.

As a result of the one-piece design of the housing upper part 20, a welding of the magnetic assembly 48 to the input shaft 26 is no longer possible in this case. Therefore, the non-rotatable connection between the input shaft 26 and the magnetic assembly 48 in this case designed as an axial plug connection. For this purpose, 48 radially elastic plug connection tongues 78 are provided on the first sensor element 31 of the magnetic assembly, which engage to form the axial connector in each case at a tangentially flattened peripheral portion 80 of the input shaft 26.

The rotationally fixed connection between the input shaft 26 and the magnetic assembly 48 is thus achieved by clamping.

In order to realize a stronger rotationally fixed connection is alternatively also conceivable to produce a positive connection through the axial connector, for example via interlocking teeth. Such a connector can be formed analogously to the embodiments shown in Figure 15 to 22.

When assembling the motor vehicle steering assembly 10, the preassembled subassembly 77 is pushed axially over the input shaft 26 and aligned in the circumferential direction so that the plug connection tabs 78 engage the flattened peripheral portion 80 and ensure a rotationally fixed connection between the input shaft 26 and the magnetic assembly 48.

The magnetic assembly 48 is mounted in the housing upper part 20, for example, floating. In this way, a rotation of the magnetic assembly 48 relative to the housing upper part 20 and possibly also a certain axial play of the magnetic assembly 48 relative to the housing upper part 20 is made possible.

After attaching the preassembled subassembly 77, this is axially secured and fixed by the snap ring 56.

As the last assembly step, the magnet ring 36 is aligned in the circumferential direction relative to the magnetic assembly 48 and fixedly connected to the output shaft 28, in particular welded.

Figures 1 1 to 14 show the motor vehicle steering assembly 10 according to another embodiment. In this case, the motor vehicle steering assembly 10 according to FIGS. 11 to 14 differs from the embodiment according to FIGS. 8 to 10 only in that case the housing upper part 20 and the entire combined steering angle and steering torque sensor 18 including the magnet ring 36 form a preassembled subassembly 81 form.

As a result, the magnet ring 36 is less accessible, so that welding to the output shaft 28 is not possible or only with increased effort.

The trained as a magnetic ring 36, the second sensor element 35 of the combined steering angle and steering torque sensor 18 accordingly has analogously to the first sensor element 31 of the magnetic assembly 48 radially elastic plug connection tongues 82, which in each case to form an axial connector on a tangentially flattened peripheral portion 84 of the output shaft Attack 28. Consequently, in this embodiment, the motor vehicle steering assembly 10, both the rotationally fixed connection between the magnetic assembly 48 and the input shaft 26 and the non-rotatable connection between the magnet ring 36 and the output shaft 28 designed as an axial plug connection.

To realize a stronger rotationally fixed connection is alternatively also conceivable to produce a positive connection through the axial connectors, for example via interlocking teeth. Embodiments for such connectors are shown in Figures 15 to 22.

The assembly of the motor vehicle steering assembly 10 takes place in this case by simply plugging the preassembled subassembly 81 on the steering shaft 12th

FIG. 14 shows a bottom view of the preassembled subassembly 81 according to FIG. 12 in the region of a rotary drive between the magnetic assembly 48 and the magnet ring 36. The magnetic assembly 48 encloses the magnet ring 36 and has projections 86 directed radially inward. On a radial outer side of the magnet ring 36 corresponding recesses 88 are provided, in which engage the projections 86 with a predetermined circumferential clearance, so that the magnetic Assembly 48 and the magnetic ring 36 are limited relative to each other rotatable.

The integration of the magnet ring 36 in the preassembled subassembly 81 in the form of a limited rotatable connection of some angular degree between the magnetic assembly 48 and the magnetic ring 36 an oriented and thus safe assembly is guaranteed.

Figures 15 to 22 show different embodiments of an axial connector for rotationally fixed coupling of the output shaft 28 with the designed as a magnetic ring 36 second sensor element 35. According to Figures 15 to 21, for illustrative reasons, only a form-locking ring 90 is shown, which firmly pre-assembled on the second sensor element 35 is. Specifically, the form-fitting ring 90 is a metal or plastic ring which is integrated into the second sensor element 35 or welded or glued thereto. It is of course conceivable to use the axial plug connections shown also for the rotationally fixed coupling of the input shaft 26 with the first sensor element 31 designed as a magnetic assembly 48. The form-locking ring 90 would then be firmly connected to the magnetic assembly 48 in this case, for example, welded or glued. If the form-locking ring 90 is formed as a metal ring and is fastened to a plastic component of the magnetic assembly 48, it can be integrated in particular by means of a plastic sheath in this plastic component, wherein the plastic sheath takes place for example by an injection molding or Spritzgformblas-. Figures 15, 16 and 17 show embodiments in which the

Output shaft 28 each have at one axial end the pinion 16 and at an opposite axial end an external toothing 92. At the fixedly connected to the second sensor element 35 form-locking ring 90, a toothing 94 is formed, which engages in the external toothing 92 to form a rotationally fixed connection between the output shaft 28 and the second sensor element 35. According to FIG. 15, the form-locking ring 90 has an internal toothing with identical tooth pitch complementary to the external toothing 92 of the output shaft 28. This leads to an axially and radially particularly compact, rotationally fixed connection between the output shaft 28 and the second sensor element 35.

Alternatively, it is also conceivable that the internal toothing of the form-locking ring 90 according to FIG. 16 has a larger tooth pitch than the external toothing 92 of the output shaft 28, which leads to a greater radial space requirement of the connection. In contrast, in order to reduce the radial space requirement, the form-fitting ring 90 according to FIG. 17 can also have circumferentially spaced, axial extensions 96, at the free axial ends of which teeth of the teeth 94 engaging in the external teeth 92 are formed. As a result, however, the space requirement in the axial direction increases slightly. Figures 18 and 19 show embodiments in which the output shaft 28 each at one axial end of the pinion 16 and at an opposite axial end grooves 98 which extend in the axial direction. Spring clips 100, which engage in the grooves 98 in order to form a rotationally fixed connection between the output shaft 28 and the second sensor element 35, are formed on the form-locking ring 90 fixedly connected to the second sensor element 35.

According to Figure 18, the spring clips 100 are designed as axial spring arms, which extend from the circumferential form-locking ring 90 in the axial direction to a free end and engage in the circumferential direction fit into the grooves 98 of the output shaft 28.

Alternatively, the circumferential interlocking ring 90 may also have circumferentially spaced, axial extensions 96, the spring clips 100 being formed at circumferentially opposite ends of the extensions 96 and extending as tangential spring arms in the circumferential direction from one of the extensions 96 to a free end. The two formed on an axial extension 96 spring arms engage in the circumferential direction accurately in each associated grooves 98 of the output shaft 28 and thereby prevent a Relative rotation between the second sensor element 35 and the output shaft 28th

Figures 20 and 21 show alternative embodiments in which circumferentially spaced spring portions 104 are formed on the form-locking ring 90. The rotationally fixed in the circumferential direction coupling with the output shaft 28 takes place in the region of the spring portions 104, whereas the form-locking ring 90 is fixedly connected between the spring portions 104 with the second sensor element 35. The form-locking ring 90 is preferably a wire ring in these embodiments, but may alternatively also be formed from a suitable plastic.

According to FIG. 20, the round outer circumference of the output shaft 28 has at one axial end the pinion 16 and at an opposite axial end flat portions 106, which form planar tangential sections. The spring portions 104 of the form-locking ring 90 extend in the radial direction to the output shaft 28 and lie in the region of the flats 106 on the output shaft 28 to provide a largely rotationally fixed connection between the second sensor element 35 and the output shaft 28.

Referring to Figure 21, the output shaft 28 has at one axial end the pinion 16 and at an opposite axial end circumferentially spaced, wide grooves 98 which extend in the axial direction. The integrally formed on the form-fitting ring 90 spring portions 104 extend axially into the grooves 98 and engage in the circumferential direction fit into the grooves 98, to form a substantially rotationally fixed connection between the output shaft 28 and the second sensor element 35. Finally, FIG. 22 shows a variant embodiment in which the output shaft 28 has the pinion 16 at one axial end and the fixed preassembled form-locking ring 90 at an opposite axial end. Depending on the design of the form-fitting ring 90 is welded or glued in particular to the output shaft 28. The form-locking ring 90 has, in this case, radially outwardly projecting projections 108 distributed over its circumference, which engage in recesses of the second sensor element 35 that fit in a complementary manner, to form a rotationally fixed connection between the output shaft 28 and the second sensor element 35.

All rotationally fixed and form-fitting coupling variants according to FIGS. 15 to 22 are advantageously designed as axial plug-in connections, so that the motor vehicle steering assembly 10 can be assembled with low assembly costs.

Claims

claims

1 . Motor vehicle steering assembly with

a steering shaft (12) extending from a vehicle steering wheel (14) to a pinion (16) and rotatable about a steering axis (A),

a combined steering angle and steering torque sensor (18) having non-rotatably connected to the steering shaft (12) connected sensor elements (31, 35), and

a housing upper part (20) of a multi-part steering gear housing (22) which closes a housing lower part (24) open in the axial direction to the vehicle steering wheel (14) for receiving the pinion (16) on the steering wheel side,

wherein the combined steering angle and steering torque sensor (18) in the housing upper part (20) is received, and

wherein the steering shaft (12) extends through the housing upper part (20), characterized in that the non-rotatably connected to the steering shaft (12) sensor elements (31, 35) directly adjacent to the housing upper part (20).

2. Motor vehicle steering assembly according to claim 1, characterized in that the steering shaft (12) connected to the vehicle steering wheel (14) input shaft (26) connected to the pinion (16) output shaft (28) and a torsion element (30), the the input shaft (26) and the output shaft (28) coupled in the circumferential direction.

3. Motor vehicle steering assembly according to claim 1 or 2, characterized in that the combined steering angle and steering torque sensor (18) comprises a first sensor element (31) having a rotationally fixed connection to the input shaft (26), and a second sensor element (35) a non-rotatable connection to the output shaft (28), wherein at least one of the non-rotatable connections is formed as an axial plug connection.

4. Motor vehicle steering assembly according to claim 3, characterized in that the first sensor element (31) or the input shaft (26) has an integrated or permanently pre-assembled form-locking ring (90) for forming the rotationally fixed connection.

5. Motor vehicle steering assembly according to claim 3 or 4, characterized in that the second sensor element (35) or the output shaft (28) has an integrated or permanently pre-assembled form-locking ring (90) for forming the rotationally fixed connection.

6. Motor vehicle steering assembly according to one of claims 3 to 5, characterized in that at least one of the sensor elements (31, 35) radially resilient plug connection tongues (78), which in each case at a tangentially flattened peripheral portion of the input shaft (26) and to form the axial connector / or the output shaft (28) attack.

7. Motor vehicle steering assembly according to one of the preceding claims, characterized in that the housing upper part (20) comprises a flange portion (38) which rotatably connected to the steering shaft (12) sensor elements (31, 35) surrounds and with the housing lower part (24) is connected.

8. Motor vehicle steering assembly according to one of the preceding claims, characterized in that the housing upper part (20) comprises a bearing portion (42) having a radial bearing (44) for rotatably supporting the steering shaft (12).

9. Motor vehicle steering assembly according to claim 8, characterized in that in the bearing section (42) a sealing element (46) for sealing between the housing upper part (20) and the steering shaft (12) is arranged.

10. Motor vehicle steering assembly according to claim 7 and 8, characterized in that the flange portion (38) and the bearing portion (42) form separate components of the housing upper part (20).

1 1. Motor vehicle steering assembly according to claim 10, characterized in that the flange portion (38) of the housing upper part (20) surrounds the combined steering angle and steering torque sensor (18) and axially between the bearing portion (42) of the housing upper part (20) and the housing Lower part (24) is arranged.

12. Motor vehicle steering assembly according to claim 10 or 1 1, characterized in that the combined steering angle and steering torque sensor (18) has a magnetic ring (36), a relative to the magnetic ring (36) rotatable magnetic assembly (48) and an electrical sensor unit (50) wherein the flange portion (38), the magnetic assembly (48) and the electrical sensor unit (50) form a preassembled subassembly (72).

13. Motor vehicle steering assembly according to claim 7 and 8, characterized in that the flange portion (38) and the bearing portion (42) of the housing upper part (20) are integrally formed.

14. Motor vehicle steering assembly according to claim 13, characterized in that the combined steering angle and steering torque sensor (18) comprises a magnetic ring (36), a relative to the magnetic ring (36) rotatable, magnetic assembly (48) and an electrical sensor unit (50) the housing top (20), the magnetic assembly (48) and the electrical sensor unit (50) form a preassembled subassembly (77).

15. Motor vehicle steering assembly according to claim 13, characterized in that the housing upper part (20) and the combined steering angle and steering torque sensor (18) form a preassembled subassembly (81).

16. Motor vehicle steering assembly according to one of the preceding claims, characterized in that the combined steering angle and

Steering torque sensor (18) comprises a magnetic ring (36), a magnetic assembly (48) and an electrical sensor unit (50), wherein the magnetic assembly (48) arranged coaxially with the steering shaft (12) and fixedly connected to the steering shaft (12) gear rim (32), and wherein the electrical sensor unit (50) comprises at least one elastically supported gear (61) meshing with the gear rim (32).