EP-4735325-A1 - STEERING SYSTEM FOR A MOTOR VEHICLE

Abstract

The present invention relates to a steering column (1) for a motor vehicle, comprising two components (3, 4) which can be shifted relative to one another and a position detection device (7) which has a sensor unit (71) connected to one component (3), which sensor unit is movable, in a shifting direction, relative to a target unit (72) connected to the other component (4), and is designed to detect the relative position of the target unit (71), wherein the target unit (71) has a target element (73) which extends in a planar manner in parallel with the shifting direction (x) and which has a measurement variable that can be detected by the sensor unit (71) and that varies along the shifting direction. In order to make improved position detection possible, according to the invention the target unit (72) has a plastics layer (75) connected to the target element (73).

Inventors

• KOROL, Daniel
• Fejes, Tamás
• WILLI, Andreas
• Vitalis, Daniel
• RIEDMANN, PATRICK
• BLÄTTLER, Simon
• Vargha, Balázs
• SZEGO, Gergo

Assignees

• thyssenkrupp Presta AG
• thyssenkrupp AG

Dates

Publication Date

20260506

Application Date

20240404

Claims (14)

1. 1. Steering column (1) for a motor vehicle, which has two components (3, 4) which can be adjusted relative to one another and a position detection device (7) which has a sensor unit (71) connected to one component (3), which is movable along an adjustment direction relative to a target unit (72) connected to the other component (4), and which is designed to detect the relative position of the target unit (71), wherein the target unit (71) has a target element (73) which extends flatly parallel to the adjustment direction (x) and which has a measured variable which can be detected by the sensor unit (71) and which varies along the adjustment direction, characterized in that the target unit (72) has a plastic layer (75) connected to the target element (73).
2. 2. Steering column according to claim 1, characterized in that the plastic layer (75) is arranged between the target element (73) and the sensor unit (71).
3. 3. Steering column according to one of the preceding claims, characterized in that the target element (73) is embedded in the plastic layer (75).
4. 4. Steering column according to one of the preceding claims, characterized in that the plastic layer (75) comprises a thermoplastic polymer or an epoxy resin.
5. 5. Steering column according to one of the preceding claims, characterized in that the target element (73) comprises a metal.
6. 6. Steering column according to one of the preceding claims, characterized in that the plastic layer (75) is flat.
7. 7. Steering column according to one of the preceding claims, characterized in that the sensor unit (71) is slidably mounted on the plastic layer (75).
8. 8. Steering column according to one of the preceding claims, characterized in that the sensor unit (71) is spring-loaded against the target unit (72).
9. 9. Steering column according to one of the preceding claims, characterized in that the target element (73) has a plate-shaped carrier element (74).
10. 10. Steering column according to one of the preceding claims, characterized in that the sensor unit (71) is designed to carry out an inductive or capacitive measuring method.
11. 11. Steering column according to one of the preceding claims, characterized in that the target element (73) is designed to converge in a wedge shape in the adjustment direction (x).
12. 12. Steering column according to one of the preceding claims, characterized in that the target element (73) is rounded in a wave-like manner in the adjustment direction (x).
13. 13. Steering column according to one of the preceding claims, characterized in that at least two target elements (73) are arranged next to one another transversely to the adjustment direction (x).
14. 14. Steering column according to claim 13, characterized in that at least two target elements (73) have a different profile of their width (y) over their length in the adjustment direction (x).

Description

steering system for a motor vehicle State of the art The invention relates to a steering column for a motor vehicle, which has two components that can be adjusted relative to one another and a position detection device that has a sensor unit connected to one component, which is movable relative to a target unit connected to the other component along an adjustment direction and which is designed to detect the relative position of the target unit, wherein the target unit has a target element that extends flatly parallel to the adjustment direction and has a measurement variable that can be detected by the sensor unit and that varies along the adjustment direction. Such a steering column has a manual steering handle for entering steering commands at its rear end in relation to the direction of travel of the vehicle, facing the driver's position, for example a steering wheel that can be rotated about a longitudinal axis in an actuating unit. At a distance from this steering wheel-side end, the steering column is attached to the vehicle body in a body-side area, usually via a support unit. To ensure that the steering wheel position can be adjusted to the driver's position in a user-friendly manner, the steering handle is adjustable relative to the vehicle body. For longitudinal adjustment, adjustment can be made in the longitudinal direction defined by the longitudinal axis, and for optional height adjustment, transversely to this in a vertical direction. To achieve longitudinal adjustment, an actuating unit carrying the steering handle can be telescopically accommodated in a casing unit, which can also be referred to as a guide box or box swing arm. The height adjustment can be achieved by pivoting the casing unit around a horizontal axis in a front area of the support unit, so that the steering handle can be pivoted in the vertical direction. For the optimal activation of steering column-related safety systems, for the automated setting of an individual steering wheel position, or to adjust the steering column in autonomous driving operation of an autonomously driving vehicle from the operating position to a distant storage position outside the operating area, it is necessary to record the current adjustment position in the respective adjustment direction. For this purpose, the state of the art, for example from EP 4 032 783 A2 or DE 10 2020 115162 A1, provides a steering column with an electronic position detection device is known which has a sensor and a cooperating sensor target for detecting the position of components which can be moved relative to one another, for example the actuating unit relative to the casing unit or the casing unit relative to the support unit. For this purpose, a sensor unit is provided which is connected to one component, for example the actuating unit, the casing unit or the support unit, and which can detect the relative linear position of a target unit which is fixed to the other component which is adjustable relative to the one component, for example the casing unit or the support unit. When the steering column is adjusted, the sensor unit is moved along the target unit in the adjustment direction. The target unit has a target element, the length of which extends in the adjustment direction, and is made of a target material that can be detected by the sensor unit without contact, for example an inductively detectable metallic material. Because the target element has a measurement variable that varies along the adjustment direction, for example an increasing width or thickness transverse to the adjustment direction, the relative position in the adjustment direction can be determined from the measurement signal of the sensor device. In order to ensure sufficient linearity and measurement accuracy of the position detection, it is necessary that the sensor unit is guided along the target element perpendicular to the target plane while maintaining a constant measurement distance. In the current state of the art, the measurement distance is determined by the width of the air gap between the sensor unit and the target element that is freely opposite it. The external influences that act during operation can affect the maintenance of a constant measurement distance over the entire adjustment path, which can have a negative effect on the linearity of the measurement. In view of the problems explained above, it is an object of the present invention to enable improved position detection. representation of the invention This object is achieved according to the invention by the steering system having the features of claim 1. Advantageous further developments emerge from the subclaims. In a steering column for a motor vehicle, which has two components that can be adjusted relative to one another and a position detection device that has a sensor unit connected to one component, which is movable along an adjustment direction relative to a target unit connected to the other component and which