DE102021201759A1 - Method of operating an electrically adjustable steering column for a motor vehicle and electrically adjustable steering column - Google Patents

Abstract

The present invention relates to an electrically adjustable steering column (1) for a motor vehicle, which has a steering input unit (2) held adjustably by a support unit (4), an electrical adjustment device (5, 6) which is functionally arranged between the support unit (4) and the steering input unit (2). and an electrical control unit (8) which is connected to an input device and which is designed to control the adjustment device (5, 6) for adjusting the steering input unit (2) relative to the support unit (4). In order to increase operational safety and ease of use, the invention proposes that the control unit (8) has an operating parameter memory (81).

Description

State of the art

The invention relates to an electrically adjustable steering column for a motor vehicle, which has a steering input unit that is held adjustably by a support unit, an electrical adjustment device that is functionally arranged between the support unit and the steering input unit, and an electrical control unit that is connected to an input device and that is designed to actuate the adjustment device for Adjustment of the steering input unit relative to the support unit. Furthermore, a method for operating such a steering column is the subject of the invention.

Such a steering column of a motor vehicle has a steering input unit for entering manual steering commands, which is also referred to below as an actuating unit, and which has, for example, a rotatably mounted steering spindle, at the rear end of which, with respect to the direction of travel, facing the driver, there is a steering wheel for introducing a steering command attached by the driver. The steering input unit is held by a support unit fixed to the vehicle body.

An electrical adjustment device comprises at least one electromotive adjustment drive which is operatively mounted between the support unit and the steering input unit and can be electrically controlled for the motorized position adjustment of the steering input unit in the vehicle interior relative to the support unit fixed to the body. A longitudinal adjustment can be effected by a longitudinal adjustment drive, for example in the axial direction of a steering spindle, and a vertical adjustment drive can be used to adjust the height. As a result, in manual driving mode, the operating or operating position of the steering input unit, for example the steering wheel, can be individually adapted to the driver's position within an operating area.

In vehicles that can be operated autonomously, the steering input device can be moved into a stowed position outside the operating area in autonomous driving mode, in which no manual steering intervention takes place, so that the vehicle interior is released for other uses. This can also make getting in and out easier.

To adjust from the operating to the stowed position or vice versa, the adjustment device is controlled by the electrical control unit with corresponding electrical control signals. The control unit can be activated by an input device, for example by switches or sensors when the ignition is switched on or off, by a door switch actuated when a vehicle door is opened or closed, or by alternative or additional sensors or monitoring devices, by which the operating or Stowage position can be requested.

Such automated control of the adjustment when an ignition switch is actuated, and additionally or alternatively by a door switch, is in the prior art CN 104670297A described. The automated control can increase driving comfort, for example for easy boarding and alighting. However, changes and deviations in the adjustment that occur during operation, for example as a result of a misalignment of the adjustment device, or also as a result of individual operating positions set within the operating area, cannot be taken into account. As a result, operational safety and ease of use can be adversely affected, in particular due to incorrect positioning of the steering input when moving from the stowed position to an operating position.

In view of the problems explained above, it is an object of the present invention to increase operational reliability and ease of use.

Presentation of the invention

This object is achieved according to the invention by the steering column having the features of claim 1 and the method for operating such a steering column according to claim 10. Advantageous developments result from the dependent claims.

In an electrically adjustable steering column for a motor vehicle, which has a steering input unit that is held adjustably by a support unit, an electrical adjustment device that is functionally arranged between the support unit and the steering input unit, and an electrical control unit that is connected to an input device and that is designed to control the adjustment device to adjust the Steering input unit relative to the support unit is provided according to the invention that the control unit has an operating parameter memory.

The operating parameter memory can preferably be integrated into the control unit and is designed to record operating data of the steering column that actually occur during operation of the adjustment device and are transmitted to or recorded by the control unit in at least one operating parameter data set to save. A stored operating data record can, for example, contain information that allows conclusions to be drawn about the functional state and the operational readiness of the adjusting device. These can include, for example, position data correlated with the electrical control signals for controlling the adjustment drive or drives, which can indicate whether a maladjustment has occurred or whether the adjustment is impeded or blocked.

Furthermore, this operating data set can include at least one error code data set, which is written to the memory when an error occurs and this provides information about the type of error. Alternatively or additionally, the error code data record can have further information correlated with the error.

Other measured variables correlated with the operation of the steering column can also be recorded and stored, for example control currents or current-voltage characteristics, which can indicate electrical and/or mechanical faults (also called faults or errors), for example due to electrical defects, Friction, wear or the like.

One advantage of the invention is that relevant operating parameters that actually occur during operation can be recorded and converted into operating parameter data records and stored in the operating parameter memory. The stored operating data can be analyzed, for example by an automated comparison with reference data that is provided in a reference data store, for example. Operating parameter data occurring in the course of operation can also be compared and analyzed so that, for example, wear and tear, faulty adjustments or maladjustments, abnormal operating states and the like can be detected.

A particular advantage of the operating parameter memory connected to the control unit according to the invention and preferably integrated with it is that an automated diagnosis of the current operating state of the steering column is made possible, taking into account the operating parameter data sets stored in the operating parameter memory.

The stored operating parameter data can be updated continuously or cyclically during operation, or event-controlled storage takes place, for example when the ignition is switched off (also known to those skilled in the art as terminal 15 or ignition plus) or the power supply is interrupted. The stored operating data can be read from the operating parameter memory the next time the vehicle is started up, for example when the ignition or the power supply in an electric vehicle is switched on, and analyzed and evaluated in an automated diagnosis in the control unit. This results in the advantage that deviations, faults and malfunctions can be reliably detected before the vehicle is put into operation, which increases operational reliability.

Position data can also be stored as operating parameter data sets, which are correlated with an individual setting of the operating position of the steering column and are defined by an adjustment state of the adjustment device. The position data can be stored after the operating position has been adjusted, or according to the adjusted operating position before the steering column is moved to the stowed position, for example when the vehicle is switched off. When readjusting from the stowed position to the operating position, it is thereby possible to adjust the adjusting device to the individual operating position corresponding to the position data read out. This results in an advantageously increased ease of use. In this case, the stored individual operating position can be set reliably and with a particularly high level of repeatability using the possibility of automated diagnosis described above, which additionally improves operational safety and comfort. The diagnosis can be carried out as an autonomous self-diagnosis of the steering column, which realizes a high level of safety and does not stress the higher-level vehicle control system.

Detected and stored deviations or malfunctions can be displayed using suitable output means. It is possible for the control unit to initiate automated measures to rectify the fault, for example an automated run to calibrate the adjustment device in the event of a misalignment. This also serves to increase comfort and security.

Calibration can be understood as a learning process. An automated run to calibrate the adjustment device can be implemented, for example, by moving the steering input unit back and forth between the mechanical end stops and thus the positions of the mechanical end stops, for example by determining the number of Hall counts using a Hall sensor in the electric motor of the adjustment device will be determined.

It is also possible that, in addition or as an alternative, further predefined or adjustable operating parameters of the steering column are stored, for example with regard to the steering and/or feedback characteristics of the steering or the like.

Provision is preferably made for the operating parameter memory to have a non-volatile memory. As a result, the stored operating parameter datasets are retained even if the power supply to the steering column is completely interrupted, in particular if the power supply is disconnected when the vehicle is being serviced or repaired. An overwritable electronic memory such as EEPROM (Electrically Erasable Programmable Read-Only Memory) or the like can preferably be used as the non-volatile memory.

Provision can be made for the control unit to be connected to a position sensor and designed to store measurement signals from the position sensor as a position data record in the operating parameter memory. Using a position sensor, which can work, for example, incrementally, optically, capacitively, inductively or according to another suitable measuring method, a real actual adjustment position can be detected and output as an electrical measurement signal. This measurement signal can be converted into a position data set, which is stored in an operating parameter data set in the operating parameter memory according to the invention. The position data can advantageously be used for diagnosing the adjustment device and for automated calibration. In addition, it is possible to detect a set individual operating position with a sufficiently high level of accuracy and to set it in a reproducible manner.

Another advantage is that the position sensor allows easy monitoring of the adjustment speed. In this way, faults due to increased friction or wear, or due to obstacles in the adjustment path, can be reliably and easily detected by means of a slower adjustment caused as a result.

In order to implement the functions explained above, it can be advantageous for the control unit to be designed to read an operating parameter data set from the operating parameter memory and to convert it into a control signal for controlling the adjusting device. This enables automated diagnosis, preferably self-diagnosis, in order to check the operational readiness of the steering column and, if necessary, bring it into an operational state, for example by calibrating the adjustment device.

It can preferably be provided that the input device comprises a sensor and/or a monitoring device. A sensor can include, for example, an electrical switch, for example an ignition switch, or a main switch in an electric vehicle, an on-board circuit breaker for disconnecting the power supply in an emergency, a door contact or the like. Alternatively or additionally, sensors functioning according to other measuring principles can also be provided, which are suitable for supplying suitable and relevant operating data for evaluating the function of the steering column. In a similar way, a monitoring device can be designed to record relevant operating data, for example to monitor the on-board electrical system, so that, for example, in the event of a voltage drop due to an empty vehicle battery or a vehicle battery that has been disconnected from the on-board electrical system, an input can be made to the control device in order to save operating parameter data sets.

It is possible for the steering input unit to include an actuating unit with a rotatably mounted steering spindle. A steering wheel is preferably attached in a manner known per se to the rear, driver-side end of the steering spindle, which steering wheel enables manual steering input to rotate the steering spindle. The steering spindle can be mounted in a telescoping jacket unit, which can optionally be variable in length, and which in turn is held by the support unit, preferably in a height-adjustable manner. In a conventional steering system or as a fallback level in an electric steering system, the steering spindle can be mechanically coupled to the steerable wheels via a steering gear. In an electric steer-by-wire steering system, the rotation of the steering spindle is detected by means of a suitable rotary sensor system and electric steering actuators, which act on the steerable wheels, are controlled by the electric steering control signals. The invention can be used particularly advantageously for steering systems in autonomously driving vehicles, which are designed as steer-by-wire steering systems and have high operational safety requirements with regard to the automated adjustment of the steering column.

The adjustment device can have a longitudinal adjustment drive and/or a height adjustment drive. The control unit can enable coordinated activation of the longitudinal and/or height adjustment drive, for example in order to implement a defined movement sequence when adjusting between the stowed and operating positions. For this purpose, the length and height adjustment drives can be operated one after the other or simultaneously. The adjustment drives can be designed in a manner known per se as spindle drives that can be driven by an electric motor.

• - Erfassen eines aktuellen Betriebszustands der Lenksäule,
• - Abspeichern eines mit dem erfassten Betriebszustand korrelierten Betriebsparameterdatensatzes in einem Betriebsparameterspeicher,
• - Auslesen des gespeicherten Betriebsparameterdatensatzes aus dem Betriebsparameterspeicher,
• - Einstellen der Lenksäule in einen Betriebszustand entsprechend dem gespeicherten Betriebsparameterdatensatz.

A method for operating an electrically adjustable steering column for a motor vehicle, which has a steering input unit that is held adjustably by a support unit and an electrical adjustment device that is functionally arranged between the support unit and the steering input unit and is controlled by a control unit for adjusting the steering input unit relative to the support unit, according to the invention comprises the steps :

• - Detection of a current operating status of the steering column,
• - Saving an operating parameter data set correlated with the detected operating state in an operating parameter memory,
• - Reading out the stored operating parameter data set from the operating parameter memory,
• - Setting the steering column in an operating state according to the stored operating parameter data set.

With regard to the explanation of the method according to the invention, full reference is made below to the preceding description of the steering column according to the invention.

In order to detect the operating state, relevant operating data is determined, for example position data correlated with an adjustment state of the adjustment device. This operating data can also contain information on other operating parameters, for example electrical and/or mechanical variables that are characteristic of the function and properties of the steering column. These can be detected by means of suitable sensors, for example by means of position sensors, and transmitted to the control unit as electrical measurement signals.

In the control unit, the incoming operating data are converted into at least one operating parameter data set, which contains the information relevant to the operating state. The operating parameter data records can be stored continuously or cyclically during operation in the operating parameter memory, or additionally or alternatively depending on an event that triggers an input signal to the control unit, for example by a sensor connected to the control unit or a monitoring device, which can be designed as described above in connection with the steering column.

The operating parameter data records stored automatically in this way can characterize a current operating state of the steering column at a point in time. Storage preferably takes place in a non-volatile manner, in particular independently of the power supply of the control unit.

An operating parameter data record is preferably stored when the vehicle is switched off by switching off the ignition or the main power supply and the steering column is still in an adjustment state corresponding to an individually set operating position. The steering column can then be brought into a stowed position outside of the operating area by the adjusting device in order to free up the vehicle interior, for example to make it easier to get out. The steering column can then be switched off and deactivated electrically. The steering column can also be deactivated in this way during autonomous driving and put into a rest state in the stowed position.

When the steering column is activated again, for example when the vehicle is started or when changing from autonomous to manual driving mode, the stored operating parameter data set is read out from the operating parameter memory. An automated diagnosis of the operating state of the steering column can be carried out by an analysis and an automated comparison of the stored operating data parameters with predetermined reference data and/or newly acquired operating data. In addition, the operating data parameters can include position data relating to the adjustment state set during storage, corresponding to an individually set operating position.

After the reading, the steering column can be set to an operating state corresponding to the stored operating parameter data set. Proceeding from this, the control unit generates and outputs control signals in order to bring the steering column into an active operating state, which corresponds to the stored operating data. In this context, it is possible for the steering column to be moved from the stowed position into the individual operating position that was set when it was saved.

It is advantageous for a diagnosis to be carried out after the operating parameter data set has been read out. The diagnosis can include checking the operating data read out for data consistency and plausibility, for example by comparison with existing data or reference data. The steering column function can also be checked, for example by measuring operating parameters and comparing them with available operating parameter data, in particular with regard to the adjustment function. This way you can faults or potential operational impairments can be detected quickly and reliably.

If the result of the diagnosis is positive, the full operating functionality of the steering column can be enabled. If the result is negative, an error message or a warning can be issued and/or the operating functionality of the steering column can be blocked or released to a limited extent. If a deviation that can be corrected is determined, for example a misalignment of the adjustment device, corrective measures can be initiated automatically as far as possible, for example a calibration of the adjustment drives. As a result, operational reliability and ease of use can be increased in an advantageous manner.

Provision can preferably be made for a signal, for example an optical, acoustic and/or haptic signal, to be output in order to inform the vehicle driver of an upcoming calibration. This signal serves as a warning.

A calibration can preferably be carried out after the reading out and/or before the storage of the operating parameter data set. This ensures an optimal operating function. By storing currently calibrated operating data, the provision of the full operating functionality when starting the vehicle can be accelerated.

As explained above in connection with the steering column, an operating parameter data set can be read out and/or stored as a function of an input signal. An input signal can be sent from an input device to the control unit, for example when an ignition lock, an ignition switch, an electrical operating switch is actuated, and/or by activating a monitoring device, such as a door contact, monitoring or control of the on-board electrical system or the like. For example, a diagnosis can always be started automatically as soon as it can be concluded with sufficient probability based on an input signal that the vehicle should be started. It is alternatively or additionally possible to carry out a diagnosis automatically after a journey.

It can be advantageous for the steering column to be moved from an operating position to a stowed position after the operating parameter data set has been stored. This makes it possible to record relevant operating data that is representative of an individually set operating position.

It can also be advantageous for the steering column to be moved from a stowed position to an operating position after the operating parameter data set has been read out. The operating position can in particular be an operating position which, for example, corresponds to the position data contained in the operating parameter data record with regard to its individual adjustment state.

character list

• 1 eine schematische perspektivische Ansicht einer erfindungsgemäßen Lenksäule,
• 2 eine weitere perspektivische Ansicht der erfindungsgemäßen Lenksäule gemäß 1,
• 3 ein Ablaufdiagramm einer Ausführung des erfindungsgemäßen Verfahrens.

Advantageous embodiments of the invention are explained in more detail below with reference to the drawings. Show in detail:

• 1 a schematic perspective view of a steering column according to the invention,
• 2 a further perspective view of the steering column according to the invention 1 ,
• 3 a flowchart of an embodiment of the method according to the invention.

Embodiments of the invention

In the various figures, the same parts are always provided with the same reference symbols and are therefore usually named or mentioned only once.

1 shows a steering column 1 according to the invention in a schematic perspective view from the top left at an angle to the rear end, based on the direction of travel of a vehicle, not shown, where a steering wheel, not shown here, is held in the operating area. 2 shows the steering column 1 in a view from the opposite side, ie seen from the top right.

The steering column 1 comprises a jacket unit 3 which has an outer jacket tube 31 , an intermediate jacket tube 32 and an inner jacket tube 33 . The jacket tubes 31, 32 and 33 are arranged axially, in the axial direction of a longitudinal axis L, coaxially telescopically adjustable, as indicated by a double arrow. As a result, a longitudinal adjustment in the direction of the longitudinal axis L is realized.

A stop 34 is attached to the rear end of the outer jacket tube 31 and protrudes inwards at the open end into the space between the outer jacket tube 31 and the intermediate jacket tube 32 . When moving out, the intermediate jacket tube 32 strikes axially against the stop 34 and is secured against separation from the outer jacket tube 31 . At the rear end of the intermediate jacket tube 32 there is a stop 35 which protrudes inward into the space between the intermediate jacket tube 32 and the inner jacket tube 33 and which secures the inner jacket tube 33 against being pulled out of the intermediate jacket tube 32 .

The shell unit 3 is held in a two-part support unit 4, which has fastening means 41 for attachment to a vehicle body, not shown.

A steering spindle 37 is mounted in the shell unit 3 so that it can rotate about the longitudinal axis L and has a connecting section 38 for attaching a steering wheel (not shown) at its rear end. Like the casing unit 3, the steering spindle 37 is also designed to be telescopic in the longitudinal direction. A steering input device has an actuating unit 2 which includes the inner jacket tube 33 together with the steering spindle 37 mounted therein. To implement a longitudinal adjustment relative to the jacket unit 3, this adjusting unit 2 is accommodated in the outer jacket tube 31 so that it can be displaced telescopically in the direction of the longitudinal axis L, in order to be able to position the steering wheel connected to the steering spindle 37 back and forth in the longitudinal direction relative to the support unit 4, as with the double arrow parallel to the longitudinal axis L indicated.

An adjusting drive 5 for the longitudinal adjustment of the actuating unit 2 relative to the casing unit 3 in the direction of the longitudinal axis L has a spindle drive with a spindle nut 51 with an internal thread 74 extending along a spindle axis G, in which a threaded spindle 52 engages, i.e. with its external thread in the corresponding one Internal thread 74 of the spindle nut 51 is screwed. The threaded spindle axis of the threaded spindle 52 is identical to the spindle axis G and runs essentially parallel to the longitudinal axis L. The adjustment drive 5 is also referred to as the longitudinal adjustment drive 5 .

The spindle nut 51 is rotatably mounted about the spindle axis G in a bearing housing 53 which is firmly connected to the outer jacket tube 31 of the jacket unit 4 . In the direction of the spindle axis G, the spindle nut 51 is supported axially on the casing unit 4 via the bearing housing 53 . The adjustment drive 5 is accordingly a so-called immersion spindle drive.

The threaded spindle 52 is connected at its free end by means of a fastening bolt 542 on an arm 36 in a rotationally fixed and axially fixed manner to the inner casing tube 33, and the spindle nut 51 is supported axially via the drive unit 53, i.e. in the longitudinal direction, on the outer casing tube 31. The longitudinal direction corresponds to the direction of the longitudinal axis L. A relative rotation by means of the motor 55 designed as an electric motor moves the threaded spindle 52 and the spindle nut 51 together or apart, depending on the direction of rotation, whereby the inner casing tube 33 axially slides into the intermediate casing tube 32, and this into the Outer jacket tube 31 is retracted or extended, as indicated by the double arrow. As a result, a steering wheel attached to the connection section 38 can be brought forward into a stowed position in which the inner casing tube 33 and the intermediate casing tube 32 are retracted into the outer casing tube 31, i.e. lowered forward, or into an operating position in the operating area in which the casing tubes 31 , 32 and 33 are telescopically extended apart.

In its front area, the shell unit 3 is mounted such that it can be pivoted relative to the vehicle body about a horizontal pivot axis S, which is shown schematically and is transverse to the longitudinal axis L. For this purpose, a pivot bearing, not shown, is arranged in the support unit 4 or between this support unit 4 and the vehicle body. In the rear area, the jacket unit 3 is connected to the support unit 4 via an adjusting lever 42 . By turning the adjusting lever 42 by means of an adjusting drive 6 (see 2 ) the shell unit 3 together with the actuating unit 2 can be pivoted relative to the support unit 4 about the pivot axis S, which is horizontal in the installed state, whereby an adjustment of a steering wheel attached to the fastening section 38 can be carried out in the vertical direction H, which is indicated by the double arrow. The adjustment drive 6 accordingly forms a height adjustment drive 6.

In 2 , which is a perspective view of the steering column 1 from FIG 1 shows the rear side, it can be seen how the adjustment drive 6 is attached to the steering column 1 for adjustment in the vertical direction H. In principle, this adjustment drive 6 has the same effect as the adjustment drive 5 . It also includes a spindle nut 61, in the internal thread of which a threaded spindle 62 engages along a spindle axis G. The threaded spindle 62 is rotatably mounted about the axis G in a bearing housing 63, which is fastened to the casing unit 3, and is supported axially, in the direction of the axis G, on the casing unit 3, and is driven by an electric drive motor 65, optionally in both directions of rotation about the Axis G can be driven in rotation. The adjusting drive 6 acts on the end of the adjusting lever 42 so that it can be pivoted by a motor for adjusting the height.

In the illustrated embodiment, the adjustment drives 5 and 6 are so-called immersion spindle drives. Alternatively, a rotary spindle drive can also be designed, in which the spindle nut 51 is held on the steering column 1 with respect to rotation and the threaded spindle 52 can be driven in rotation by the motor 55 .

The two adjusting drives 5 and 6 are part of an electromotive adjusting device Device which makes it possible to adjust the steering column 1 and thus a steering wheel attached to the steering shaft 37 at the driver-side connection section 38 relative to the vehicle body in the longitudinal and vertical directions.

A control unit 8 is connected to the adjustment drives 5 and 6 via electrical control lines 80 . The motors 55 and 65 for adjusting the casing unit 3 can be controlled via the control lines 80 . It is also possible for the adjustment drives 5, 6 to send feedback to the control unit 8 via the control lines 80, for example position signals which indicate the current adjustment state. For this purpose, the adjustment drives 5 and 6 can also have electrical sensors, not shown, for example position sensors for detecting the adjustment state or the like.

The control unit 9 is connected to an on-board electrical system 9 of the motor vehicle via a power supply line 90 . The vehicle electrical system 9 has a switch 91, for example an ignition switch, a main switch of an electric vehicle, or a circuit breaker to disconnect the vehicle battery from the vehicle electrical system 9 in an emergency.

The control unit 8 has an operating parameter memory 81, for example an EEPROM, which can preferably be designed to be integrated with the control unit 8. The operating parameter memory 81 is designed and connected to the control unit 8 in such a way that operating parameter data sets containing operating parameter data can be stored and read out by the control unit 8 .

An input device 82 , which can also be designed as a combined input/output device, is also connected to the control unit 8 via a control line 83 . Input device 82 has input and actuating means for activating the adjustment drive by control unit 8, for example manual actuating switches for setting an optimal operating position of steering column 1. Electrical door switches, main switches or other input means can also be configured in input device 82 or connected to it. As a result, for example, the control unit 8 can cause the steering column to be moved into a stowage or operating position in an event-controlled manner.

A display means 84 can be connected to the input device 82, for example an optical and/or acoustic signal transmitter.

In 3 the sequence of a method designed according to the invention is shown schematically. The method starts in a first method step 100 with the starting of the vehicle or with the activation of the electrical system of the vehicle, for example by turning on a main or ignition switch 91 (power ON). In a query 110 it is checked whether a switch-on has taken place. If this is not the case 110N, the query 110 is performed again. If query 110 is confirmed in positive case 110Y, in a method step 111 operating parameter data, namely at least one operating parameter data record, is read out from operating parameter data memory 81.

The operating parameter data preferably include position data which are correlated with at least one adjustment position of the adjustment drives 5 and 6 of the adjustment device.

The operating parameter data read out are checked in a next method step 120 in a diagnosis. In the negative case 120N of the diagnosis, corrective measures are initiated automatically as far as possible. In the exemplary embodiment shown, a calibration 130 of the adjustment device with the adjustment drives 5.6 takes place.

After successful calibration 130, operating parameter data corresponding to the current, calibrated operating state are recorded. Subsequently, updated operating parameter data sets are stored 112 in the operating parameter data memory 81.

The updated operating parameter data sets are read out again in method step 111 and checked.

In the positive case 120Y, if the operating parameter data are plausible and/or correspond to specified reference data, the full steering column functionality is released 140 .

After the release 140 has taken place, the steering column function is started in step 150 . The steering column 1 can be adjusted by means of the adjustment drives 5.6 of the adjustment device in order to automatically set an adjustment state that corresponds to the operating parameter data read out in step 111, for example position data of an individually set operating position.

A query 160 checks whether the vehicle has been switched off, ie whether the above-mentioned positive case 110Y has been canceled. In the negative case 160N, the adjusting device is still active, and an adjustment can take place, for example wise from the stowed to an operating position, or vice versa, or an adjustment to an individual operating position within an approved operating range.

If the vehicle is switched off, for example by switching off or disconnecting a main or ignition switch 91 (Power OFF), the positive case 160Y occurs, and in the next step 170 the steering column function is ended. The relevant operating parameter data are recorded, preferably in the current operating state when switching off. This operating parameter data can include position data of an individually adjusted adjustment position, for example. Other operating parameter data can also be recorded, for example supply currents of the motors 55, 65, which allow conclusions to be drawn about drive power, friction, wear and the like.

In the next step 180, an operating parameter data set correlated with the detected operating state is stored in an operating parameter memory 81.

After saving 180, a shutdown 190 takes place, with the operating parameter data stored non-volatile in the EEPROM of the operating parameter data memory being retained until the next start 100.

Reference List

1

steering column

2

actuator

21

fasteners

22, 23

swivel bearing

3

sheath unit

31

outer jacket pipe

32

intermediate casing pipe

33

inner casing tube

34, 35

attack

36

poor

37

steering spindle

38

connector section

4

carrying unit

41

fasteners

42

lever

43, 44

swivel bearing

5.6

adjustment drive

51, 61

spindle nut

52, 62

lead screw

53, 63

bearing housing

542

mounting bolts

55, 65

engine

8th

control unit

80

control line

81 9

electrical system

90

power supply line

91

Switch

L

longitudinal axis

S

pivot axis

H

height direction

G

Spindle axis (threaded spindle axis)

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent Literature Cited

• CN 104670297A [0006]

Claims (15)

Electrically adjustable steering column (1) for a motor vehicle, comprising a steering input unit (2) held adjustably by a support unit (4), an electrical adjustment device (5, 6) arranged functionally between the support unit (4) and the steering input unit (2), and an electrical control unit ( 8) which is connected to an input device and which is designed to control the adjusting device (5,6) for adjusting the steering input unit (2) relative to the support unit (4), characterized in that the control unit (8) has an operating parameter memory (81 ) having. steering column claim 1 , characterized in that the operating parameter memory (81) has a non-volatile memory. Steering column according to one of the preceding claims, characterized in that the control unit (8) is connected to a position sensor and is designed to store measurement signals from the position sensor as a position data set in the operating parameter memory. Steering column according to one of the preceding claims, characterized in that the control unit (8) is designed to read an operating parameter data set from the operating parameter memory (81) and to convert it into a control signal for actuating the adjusting device (5, 6). Steering column according to one of the preceding claims, characterized in that the input device comprises a sensor and/or a monitoring device. Steering column according to one of the preceding claims, characterized in that the steering input unit (2) comprises an actuating unit (2) with a rotatably mounted steering spindle (37). Steering column according to one of the preceding claims, characterized in that the steering input unit (2) has a feedback actuator. Steering column according to one of the preceding claims, characterized in that the adjustment device (5, 6) has a longitudinal adjustment drive (5) and/or a vertical adjustment drive (6). Method for operating an electrically adjustable steering column (1) for a motor vehicle, which has a steering input unit (2) held adjustably by a support unit (4) and an electrical adjusting device (5, 6) arranged functionally between the support unit (4) and the steering input unit (2). , which is controlled by a control unit (8) for adjusting the steering input unit (2) relative to the support unit (4), characterized by the steps: - detecting a current operating state of the steering column (1), - storing an operating parameter data set correlated with the detected operating state in an operating parameter memory (81), - reading out the stored operating parameter data set from the operating parameter memory (81), - setting the steering column (1) in an operating state corresponding to the stored operating parameter data set. procedure after claim 9 , characterized in that the operating data parameters include position data. Method according to any of the foregoing claims 9 or 10 , characterized in that a diagnosis is carried out after the operating parameter data set has been read out. Method according to any of the foregoing claims 9 until 11 , characterized in that a calibration is carried out after reading out and/or before storing the operating parameter data set. Method according to any of the foregoing claims 9 until 12 , characterized in that an operating parameter data set is read out and/or stored as a function of an input signal. Steering system according to one of the preceding claims, characterized in that after the operating parameter data set has been stored, the steering column is moved from an operating position to a stowed position. Steering system according to one of the preceding claims, characterized in that after the operating parameter data set has been read out, the steering column is brought from a stowed position into an operating position.

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