METHOD FOR OPERATING A STEERING SYSTEM FOR A MOTOR VEHICLE AS WELL AS A CORRESPONDING STEERING SYSTEM

20200130731 · 2020-04-30

Assignee

Inventors

Cpc classification

International classification

Abstract

A method for operating a steering system for a motor vehicle, wherein the steering system has at least one steering lever and at least one electric motor for shifting the steering lever so as to cause a steering movement in the presence of a steering input, and wherein the electric motor is electrically connected to a current source via cabling. In doing so, it is provided that the electric motor is actuated and an electric current flowing between the current source and the electric motor is measured in order to check an electrical connection between the current source and the electric motor under the condition that there is no steering input present.

Claims

1. A method for operating a steering system for a motor vehicle, wherein the steering system has at least one steering lever and at least one electric motor for shifting the steering lever so as to cause a steering movement in the presence of a steering input, and wherein the electric motor is electrically connected to a current source via cabling, wherein the electric motor is actuated and an electric current flowing between the current source and the electric motor is measured in order to check an electrical connection between the current source and the electric motor under the condition that there is no steering input present, wherein the electric motor is actuated to generate or receive reactive current such that the steering movement stops, and/or the electric motor is actuated for shifting the steering lever, wherein the actuation takes place when the vehicle is stopped and/or with a steering lever set by means of a locking mechanism.

2. The method according to claim 1, wherein an alternating current motor or a three-phase motor is used as the electric motor.

3. The method according to claim 1, wherein the actuation to generate or receive the reactive current takes place by applying a direct-current or at least a direct-current portion to the electric motor.

4. The method according to claim 1, wherein the actuation takes place when the motor vehicle is stopped, when it is determined that a driver of the motor vehicle is not in a driver's seat of the motor vehicle and/or in an interior of the motor vehicle, and/or upon unlocking of at least one door of the motor vehicle or upon actuation of an ignition lock from a locked setting.

5. The method according to claim 1, wherein the electric motor is actuated such that it effects an actuating force on the steering lever, wherein the actuating force is less than the static friction force between at least one substrate of the motor vehicle and a wheel of the motor vehicle, said wheel being arranged on the substrate and steerable by means of the steering lever.

6. The method according to claim 1, wherein a position of the steering lever is determined during the actuation, and the actuating force is reduced in the event of a change in the position.

7. The method according to claim 1, wherein the actuation only occurs with a steering lever set by means of the locking mechanism.

8. The method according to claim 1, wherein the locking mechanism for setting the steering lever is set before the actuation.

9. The method according to claim 1, wherein the locking mechanism provides an end stop for the steering lever, against which the steering lever is pushed due to the actuation of the electric motor.

10. A steering system for a motor vehicle, comprising: at least one steering lever and at least one electric motor for shifting the steering lever so as to cause a steering movement in the presence of a steering input, and wherein the electric motor is electrically connected to a current source via cabling, wherein the steering system is designed to check an electrical connection between the current source and the electric motor under the condition that there is no steering input present, to actuate the electric motor, and to measure a current flowing between the current source and the electric motor, wherein the electric motor is actuated to generate or receive reactive current such that the steering movement stops, and/or the electric motor is actuated for shifting the steering lever, wherein the actuation takes place when the vehicle is stopped and/or with a steering lever set by means of a locking mechanism.

11. The method according to claim 2, wherein the actuation to generate or receive the reactive current takes place by applying a direct-current or at least a direct-current portion to the electric motor.

12. The method according to claim 2, wherein the actuation takes place when the motor vehicle is stopped, when it is determined that a driver of the motor vehicle is not in a driver's seat of the motor vehicle and/or in an interior of the motor vehicle, and/or upon unlocking of at least one door of the motor vehicle or upon actuation of an ignition lock from a locked setting.

13. The method according to claim 3, wherein the actuation takes place when the motor vehicle is stopped, when it is determined that a driver of the motor vehicle is not in a driver's seat of the motor vehicle and/or in an interior of the motor vehicle, and/or upon unlocking of at least one door of the motor vehicle or upon actuation of an ignition lock from a locked setting.

14. The method according to claim 2, wherein the electric motor is actuated such that it effects an actuating force on the steering lever, wherein the actuating force is less than the static friction force between at least one substrate of the motor vehicle and a wheel of the motor vehicle, said wheel being arranged on the substrate and steerable by means of the steering lever.

15. The method according to claim 3, wherein the electric motor is actuated such that it effects an actuating force on the steering lever, wherein the actuating force is less than the static friction force between at least one substrate of the motor vehicle and a wheel of the motor vehicle, said wheel being arranged on the substrate and steerable by means of the steering lever.

16. The method according to claim 4, wherein the electric motor is actuated such that it effects an actuating force on the steering lever, wherein the actuating force is less than the static friction force between at least one substrate of the motor vehicle and a wheel of the motor vehicle, said wheel being arranged on the substrate and steerable by means of the steering lever.

17. The method according to claim 2, wherein a position of the steering lever is determined during the actuation, and the actuating force is reduced in the event of a change in the position.

18. The method according to claim 3, wherein a position of the steering lever is determined during the actuation, and the actuating force is reduced in the event of a change in the position.

19. The method according to claim 4, wherein a position of the steering lever is determined during the actuation, and the actuating force is reduced in the event of a change in the position.

20. The method according to claim 5, wherein a position of the steering lever is determined during the actuation, and the actuating force is reduced in the event of a change in the position.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The invention is explained in more detail in the following by means of exemplary embodiments, without limiting the invention. In doing so, the only

[0035] FIG. 1 shows a schematic representation of a steering system for a motor vehicle.

DETAILED DESCRIPTION

[0036] FIG. 1 shows a schematic representation of a part of a steering system 1, which can be used, for example, for a motor vehicle. The steering system 1 has two steering levers, 2 and 3, which are each effectively connected to a wheel carrier 4, particularly rigidly connected. A wheel 5 of the motor vehicle is rotatably mounted on each of the wheel carriers 4. The wheel carriers 4 are each rotatably mounted about an axis of rotation 6 on a part of a body 7 of the motor vehicle, for example on a crossmember 8.

[0037] In the exemplary embodiment shown here, the steering levers, 2 and 3, which are in the form of steering arms, are connected to one another via a tie rod 9. The tie rod 9 is rotatably mounted about an axis of rotation, 10 and/or 11, on each of the steering levers, 2 and 3. The axis of rotation, 10 and/or 11, is arranged some distance from respective axis of rotation 6 in this case such that a displacement of the tie rod 9, particularly a linear displacement of the tie rod 9, effects a rotational movement of the wheel carriers 4 about respective axis of rotation 6.

[0038] In the exemplary embodiment shown here, the steering system 1 has a drive 12, which has at least one electric motor 13. The electric motor 13 is coupled to the tie rod 9. The electric motor 13 engages the tie rod 9 directly in this respect. The drive 12 is electrically connected to a current source 15 via cabling 14. In order to check the electrical connection between the drive 12 and the current source 15, it is then provided to actuate the drive 12. The actuation takes place only under the condition that there is no steering input present. Actuation of the electric motor 13 takes place such that it generates or accepts a reactive current, wherein the steering movement is stopped. Additionally or alternatively, the electric motor 13 is actuated for shifting the steering lever, 2 or 3, wherein the actuation takes place when the vehicle is stopped and/or with a steering lever, 2 or 3, set by means of a locking mechanism.

[0039] During the actuation of the drive 12, an electric current flowing between the current source 15 and the drive 12 is measured. By means of the measured current, for example by means of the current strength of the electric current, a conclusion is subsequently made about the functionality of the steering system 1 and/or a proper state of the electrical connection.