Method for capturing the position of two movable components of a steering column for a motor vehicle, and steering column for a motor vehicle

Abstract

The present invention relates to a method for capturing the position of two movable components (21, 22) of a steering column (1) for a motor vehicle, which are able to be moved relative to one another in a movement direction over a plurality of movement ranges (V1, V2, V3), wherein the relative position of the components (21, 22) is captured as a position value by a sensor (72) of f position-capturing device (7). The aim of the invention is to allow improved position capturing with relatively little complexity. To achieve this aim, according to the invention at least two sensors (73, 74) of the position-capturing device (7) capture a position value (P1, P2) for each of the movement regions (V1, V2, V3), each of the movement regions (V1, V2, V3) being assigned a clearly distinguishable combination of the at least two position values (P1, P2) of the at least two sensors (73, 74).

Description

[0001] Method for detecting the position of two adjustable components of a steering column for a motor vehicle and steering column for a motor vehicle

[0002] State of the art

[0003] The invention relates to a method for detecting the position of two adjustable components of a steering column for a motor vehicle, which components are adjustable relative to one another in an adjustment direction over a plurality of adjustment ranges. The relative position of the components is detected as a position value by a sensor of a position detection device. A position value is detected for each of the adjustment ranges by at least two sensors of the position detection device. A clearly distinguishable combination of the at least two position values ​​of the at least two sensors is assigned to each of the adjustment ranges. A steering column for implementing the method is also the subject of the invention.

[0004] A motor-adjustable steering column enables the automated adjustment of an ergonomic operating position for manual operation of the steering input device, such as a steering wheel, by adjusting it relative to the driver's position. The adjustment can be made within an operating range, also referred to as the comfort zone. In autonomously operated vehicles, it may also be possible to stow the steering input device in autonomous ferry operation, when no manual steering input is provided, outside the operating range in a storage area away from the operating position by further adjusting it.A transition zone extends between the operating area and the stowage area, through which the adjustable component is retracted from the operating area to the stowage area by means of an electric adjustment drive for stowing, or extended in the opposite direction from the stowage area to the operating area for un-stowing and activating manual operating mode. The operating area, the transition zone, and the stowage area are also generally referred to below as the adjustment zones.

[0005] In the prior art, a method for controlling a steering column is known from DE 10 2019 120 543 B4. The adjustment can be adjusted over the entire possible adjustment range using the aforementioned adjustment ranges. For automated control of the adjustment, a suitable sensor is used to detect the position between two components that can be adjusted relative to one another, for example, between longitudinally telescopic steering column tubes. This makes it possible to detect which of the aforementioned adjustment ranges is currently set.

[0006] Access authorizations and restrictions can be automatically assigned to the various adjustment ranges during vehicle operation. For example, manual steering intervention should generally be prohibited in the stowage area, and limited manual access to certain steering functions should be permitted in the transition area according to predefined safety criteria. These access definitions are highly relevant for vehicle safety, and the safe and trouble-free detection of the steering column position adjustment ranges is particularly important for the practical implementation of automated safety functions. Starting with a calibration, for example, at the start of operation, it is fundamentally possible to enable relative position detection by counting drive or measurement pulses from the motor drive.The disadvantage of such relative measurements, however, is that errors in the acquisition of measurement pulses can result in unacceptably high deviations during operation, making it impossible or only possible to meet the high safety and performance requirements with considerable effort. An alternative option, determining the position using sufficiently high-resolution absolute value measurements, also requires a relatively high level of effort and installation space.

[0007] A generic method is described in JP 2023 010104 A. This is based on the use of two sensors, the first of which can detect the position of a first component relative to a second component, and the second of which can detect the position of the second component relative to a third component. This means that distinguishing between two different adjustment ranges requires the existence of at least three components that can be mechanically adjusted relative to one another, and implementation is correspondingly complex.

[0008] In view of the problems explained above, it is an object of the present invention to enable improved position detection with less effort.

[0009] Description of the invention

[0010] This object is achieved according to the invention by the method having the features of claim 1 and the steering column according to claim 10. Advantageous further developments emerge from the subclaims.In a method for detecting the position of two adjustable components of a steering column for a motor vehicle, which components are adjustable relative to one another in an adjustment direction over a plurality of adjustment ranges, wherein the relative position of the components is detected as a position value by a sensor of a position detection device, in which a position value is detected for each of the adjustment ranges by at least two sensors of the position detection device, wherein a clearly distinguishable combination of the at least two position values ​​of the at least two sensors is assigned to each of the adjustment ranges, it is provided according to the invention that a target element is detected by the two sensors, which are both fixed to one of the components, which target element is attached to a component which is adjustable relative thereto and has at least two switching elements, which are each assigned to one of the sensors.

[0011] In the method according to the invention, the target element, which is preferably designed as a single piece and has at least two switching elements, is fixed to a first component, and a sensor or sensor element is assigned to each of these switching elements. These at least two sensors are jointly fixed to a second component that is adjustable relative to the first component. Thus, during each adjustment process, all switching elements are always moved together with the target element relative to the sensors.

[0012] In the prior art mentioned at the beginning, at least two physically defined pairs of mutually adjustable components must be provided to detect two different adjustment ranges, for example one pair consisting of a second component adjustable relative to a first component, and another pair consisting of a third component adjustable relative to the second component. Consequently, at least three components adjustable relative to one another are absolutely necessary. In contrast, with the method according to the invention, two or more adjustment ranges can be defined between two components adjustable relative to one another. This can be easily achieved by a defined arrangement of switching elements on the target element connected to a first component, which can be detected by the sensors attached to a second component.This results in the significant advantage that different numbers and / or dimensions of adjustment ranges can be defined with little effort, regardless of the physical arrangement and number of components that can be adjusted relative to one another. The number of adjustment ranges can be defined virtually, so to speak, by the number of switching elements and sensors. Advantageously, three or more adjustment ranges can be realized in a longitudinally adjustable steering column in which a single inner casing telescopically extends into an outer casing. This can also be achieved in the same way with a multiple telescope in which one or more intermediate casings are arranged between the inner and outer casings. The length of the adjustment ranges can be simply specified by the arrangement of the switching elements on the target element, preferably by their spacing in the adjustment direction.

[0013] According to the invention, the position is determined by means of at least two sensors arranged in parallel with respect to the measurement of the relative movement of the adjustable components. The sensors are preferably independent. Each of the sensors can detect at least one specific, separate position value for each of the adjustment ranges according to a measurement specification. The position values ​​detected by the independent sensors together form a set of position values, with the number of position values ​​corresponding to the number of sensors. Such a set of position values ​​can be used to implement a code pattern that is characteristic of one adjustment range and exclusive to each adjustment range.

[0014] One advantage is that the method according to the invention can be designed to be more robust and reliable than, for example, a relative measurement based on counting measurement pulses. Because each of the adjustment ranges is assigned at least two position values, which can be detected by the preferably independent sensors, a clear demarcation when measuring the adjustment ranges is possible with little metrological effort. In principle, the invention only requires the measurement of a transition between adjustment ranges and then to evaluate it. This enables simpler and more reliable measurement than position determination using known absolute value sensors. As a further advantage, the at least two sensors can achieve increased measurement redundancy.

[0015] A further advantage of the method according to the invention can be realized in that the switching elements are positioned on the target element at a distance from mechanical end stops, which mechanically limit the maximum possible relative adjustment of the components.

[0016] By means of the method according to the invention, an optimized calibration of the adjustment can also be carried out at high speed. For this purpose, the two components are adjusted relative to one another until the first sensor detects the first switching element, which occurs during the transition from a first to a second adjustment range. A position value assigned to this position can be stored as a first reference value. Likewise, the two components can be adjusted relative to one another until the second sensor detects the second switching element, which occurs during the transition from a second to a third adjustment range. A position value assigned to this position can be stored as a second reference value. The position detection for calibration can also take place in the opposite adjustment direction, i.e. during the transition from the second to the first adjustment range or from the third to the second adjustment range.In this way, a simple calibration routine can reliably detect and compensate for any potential play in the adjustment caused by mechanical tolerances.

[0017] A particular advantage can be achieved by arranging the switching elements at a distance from mechanical end stops. This allows for extremely high relative adjustment without the risk of a potentially damaging hard mechanical end stop occurring at the end of the maximum adjustment range in the event of an adjustment error, which may occur before calibration. This can accelerate calibration.

[0018] It can be provided that a position value is recorded digitally. Each of the adjustment ranges can be uniquely assigned a binary position value, i.e., a digital "1" or "0" is recorded as a measured value by one of the sensors for an adjustment range according to a measurement specification. This allows a unique binary code pattern to be generated for each adjustment range from the measured values ​​of the sensors. Such a digital measurement can be implemented with little effort using known measuring methods, e.g., magnetic or inductive measurement or the like, and enables robust data acquisition with high accuracy. In this way, the high safety requirements of autonomous driving can be easily met.

[0019] It can be provided that a position value is recorded in analog form. Each of the adjustment ranges can be uniquely assigned a quasi-binary position value, i.e., a high level "1" or a low level "0" is recorded as the measured value for an adjustment range by one of the sensors according to a measurement specification. This allows a unique binary code pattern to be generated for each adjustment range from the measured values ​​of the sensors. Thanks to the analog design, errors are easy to detect. If a sensor is defective, no signal is output instead of a low level. With an analog design, the measured value / position value "0" is synonymous with a low level, also referred to as LOW, and the measured value / position value "1" is synonymous with a high level, also referred to as HIGH.

[0020] A practical example can be implemented as follows: A first sensor (sensor 1) detects a first position value, for example, a digital "0," in a first adjustment range (e.g., an operating range), a second position value, for example, a digital "1," in a second adjustment range (e.g., a transition range, which can also be referred to as an extended adjustment range), and a third position value, for example, a digital "1," in a third adjustment range (e.g., a storage range). In parallel, a second sensor (sensor 2) detects a first position value, for example, a digital "0," in the first adjustment range, a second position value, for example, a digital "0," in the second adjustment range, and a third position value, for example, a digital "1," in the third adjustment range. This can be represented in a table as follows:

[0021] The two position values ​​detected by sensors 1 and 2 indicate a specific binary code pattern for each of the areas, namely for the stowage area (1 , 1), for the transition area (1 , 0) and for the operating area (0, 0).

[0022] It can be advantageous for a sensor position value to be switched when transitioning between adjustment ranges. The adjustment ranges define the total possible adjustment path in the sum of their extent in the adjustment direction and are each arranged adjacently in the adjustment direction or border on one another. If the adjustable component is moved from one adjustment range to another adjacent adjustment range when adjusting the steering column, a position value (state value) existing for one adjustment range can either remain the same when passing the boundary between the adjustment ranges or be changed in a defined way to another position value, for example, digitally switched from an "0" state to a "1" state or analogically switched from a low level to a high level, or vice versa. The switching is reversible, i.e.When changing in one adjustment direction, switching occurs in one switching direction, and when changing in the opposite adjustment direction, switching occurs in the opposite switching direction.

[0023] In the above example, sensor 1 is not switched during the transition from the first to the second adjustment range, retaining the position value "1." It is then switched to the position value "0" during the transition from the second to the third adjustment range. Sensor 2 is switched from "1" to "0" during the transition from the first to the second adjustment range, and retains this position value during the transition from the second to the third adjustment range.

[0024] An advantage of the aforementioned approach is that only two switching operations are required for the three available adjustment ranges, meaning that each of the two sensors only needs to be switched once during the entire adjustment range. This allows the determination of which adjustment range the adjustable component is currently in to be carried out reliably and with minimal effort, while maintaining high measurement accuracy.

[0025] An advantageous possibility for implementing the aforementioned switching can be achieved by switching a position value using a switching element. Each of the sensors can be assigned at least one switching element, which is positioned at the boundary of two adjustment ranges. The switching element can comprise a detectable switching threshold, for example a switching threshold that can be detected magnetically, mechanically, optically, or by means of another suitable measuring method. This can be used, for example, to generate a rising signal edge during the transition from one adjustment range to an adjacent adjustment range in one adjustment direction, which indicates, for example, a change in the position value from "0" to "1", and conversely, a change from "1" to "0" in the opposite adjustment direction.The hysteresis can be kept so low with little effort that position determination can be achieved with a high measurement accuracy.

[0026] An advantageously simple and robust design can be achieved by having fewer switching elements than the number of adjustment ranges. This allows the number of switching operations to be kept relatively low. Provision can be made for a position value to be stored. When transitioning between two adjustment ranges, for example when a switching threshold is exceeded, a switching pulse can be generated which updates the position value. To ensure that this updated position value, which is representative of the adjustment range reached, is retained within the entire adjustment range, it can be stored electronically until a switchover can occur at a later time during further adjustment when transitioning to a different adjustment range. Such electronic storage can be implemented reliably and with little effort.

[0027] It is possible for at least one of the sensors to detect a position value as an absolute measurement value. Within an adjustment range, the respective sensor can detect a measurement value that is preferably essentially constant for the respective adjustment range. This can, for example, be a measurement value that corresponds to a binary position value of "1" or "0" over the entire extent of an adjustment range. Such absolute value detection can be provided as an alternative or in addition to the aforementioned switching via a switching threshold and enables an additional redundant design of the position detection. This can further increase the level of safety.

[0028] Preferably, the components can be provided with at least two casing tubes that can be telescoped in a longitudinal direction. The two or more telescopically nested casing tubes form a casing unit that can be adjusted in the longitudinal direction. The longitudinal direction can preferably be defined by a longitudinal axis around which a steering spindle is rotatably mounted in the casing unit, to which a steering wheel or the like can be attached as a manual steering input means. This allows for longitudinal adjustment, which allows the steering input means to be moved forward in the direction of travel, away from the driver's position, into the stowed position.

[0029] Additionally or alternatively, it is possible for the components to comprise a support unit and a longitudinally extending casing unit, wherein the support unit supports the casing unit in a height direction that is adjustable perpendicular to the longitudinal direction. This allows for a height adjustment of a steering input device mounted at the rear end, facing the driver's position, with respect to the direction of travel.

[0030] Preferably, longitudinal and vertical adjustment can be implemented in combination. The adjustment can preferably be performed by an electric motor-driven adjustment drive. This can be controlled automatically depending on the position values. One or more adjustment drives can be provided for adjustment in the longitudinal and / or vertical directions.

[0031] The method according to the invention can preferably be used for longitudinal adjustment and also for height adjustment.

[0032] Preferably, the adjustment areas can include a storage area (storage zone), a transition area (adjustment zone), and an operating area (comfort zone). This makes it possible to reliably and precisely record the essential adjustment states of an automatically stowable steering column, while easily meeting the high safety requirements for autonomous and manual ferry operation.

[0033] However, the number and arrangement of the adjustment ranges is not limited to the three aforementioned areas. For example, it is conceivable and possible to provide a further subdivision into sub- or intermediate ranges, both longitudinally and vertically. This allows for more differentiated operating and functional options. For example, it is also possible to define non-permissible adjustments, i.e., certain combinations of longitudinal and vertical adjustments that should not be used, for example, to ensure occupant safety or to avoid mechanical collisions between vehicle components.

[0034] The method according to the invention can preferably be implemented by means of at least one electric adjustment drive, which enables motorized adjustment of the components that can be adjusted relative to one another. The adjustment drive can be designed in a conventional manner, for example, as an electric motor-driven spindle drive that engages telescopic jacket tubes for longitudinal adjustment and / or is used for height adjustment between a jacket or actuating unit and a body-side support unit.

[0035] The control of one or more electric adjustment drives for packing and unpacking the steering column can be automated according to the method according to the invention.

[0036] In a steering column for a motor vehicle, comprising two components that are adjustable relative to one another in an adjustment direction over a plurality of adjustment ranges and a position detection device that has a sensor for determining the relative position of the components, wherein the sensor is designed to detect position values ​​specific to the adjustment ranges, the invention provides that the position detection device has at least two sensors, wherein a position value can be detected by a sensor for each of the adjustment ranges, and wherein the sensors are adapted to the adjustment ranges in order to detect a clearly distinguishable combination of at least two position values ​​for each of the adjustment ranges, the invention provides that at least two sensors are fixed to one of the components, and wherein a target element is attached to a component that is adjustable relative thereto,which has at least two switching elements, each of which is assigned to one of the sensors.,

[0037] The target element can preferably be designed as a single piece and have at least two switching elements. It is fixed to a first component, and each of the at least two switching elements is assigned to a sensor or sensor element, respectively. These at least two sensors are jointly fixed to a second component that is adjustable relative to the first component. During an adjustment process, all switching elements are thus always moved together with the target element relative to the sensors.

[0038] The target element can preferably be designed to be elongated in the direction of a longitudinal axis, in which an inner casing telescopically adjustably inserts into an outer casing of a steering column. It can preferably be connected to the inner casing in its front region and extend rearwardly as far as the sensor unit, which is fixed to the outer casing. This makes it possible to define three or more adjustment ranges for the longitudinal adjustment. The lengths of the individual adjustment ranges can be predetermined by the position of the switching elements on the target element, regardless of the design of the telescopic arrangement. This is also possible with a multiple telescopic arrangement, in which one or more intermediate casings can be integrated telescopically adjustably between the inner and outer casing.

[0039] In the design of the steering column according to the invention, the features mentioned above explicitly or implicitly in connection with the method according to the invention can be implemented.

[0040] According to the invention, at least two sensors parallel with respect to the adjustment direction are provided.

[0041] The sensors are preferably designed independently to independently detect position values ​​assigned to the adjustment ranges. The sensors can be designed to implement magnetic, inductive, or other known measuring methods in order to be able to implement the method according to the invention explained above.

[0042] It is advantageous to have a switching element designed to switch a sensor between two adjustment ranges. This enables reversible switching of the position value when the sensor is moved to another adjustment range and passes the switching element in the adjustment direction.

[0043] An advantageous practical implementation can be achieved by having each sensor comprise a magnetic sensor, for example, a Hall or GMR sensor element, and a switching threshold provided by a magnet attached to the component that is adjustable relative to it, preferably at the boundary between two adjustment ranges. This enables contactless detection with high reliability and low effort. Alternatively, a light barrier or similar device can also be used.

[0044] A further advantageous practical embodiment can be realized by incorporating a magnet into the sensor element, so that the adjustable component interferes with the magnetic field, thereby causing switching, preferably at the boundary between two adjustment ranges. This enables contactless detection with high reliability and low effort. Alternatively, a light barrier or similar device can also be used.

[0045] It can be provided that a sensor is connected to a memory device in which a position value can be stored. Upon transition over a switching threshold, for example, a switching pulse can be generated that switches the position value. The position value thus generated is stored and retained until a further transition causes another switch.

[0046] Alternatively or additionally, it is possible for a sensor to be configured to detect an absolute measured value associated with an adjustment range. An adjustment range can, for example, be configured to provide a substantially constant characteristic measured variable that extends throughout its entire range and can be detected by the sensor through an absolute measurement. This can be detected alternatively to the aforementioned switching threshold, or in addition to enable greater redundancy.

[0047] It may be expedient to provide a digitizing device for digitizing the position values. A measured value output by a sensor element, for example, an analog electrical current or voltage value, can thus be made available for further data processing.

[0048] Preferably, components can have at least two casing tubes that can be telescoped in a longitudinal direction and / or a support unit and a casing unit extending in the longitudinal direction, wherein the support unit supports the casing unit so as to be adjustable in a height direction transverse to the longitudinal direction. In this way, the method according to the invention can be implemented with longitudinal and / or height adjustment.

[0049] The steering column is preferably designed to be electrically adjustable. An electric adjustment drive is provided for longitudinal adjustment, which engages telescopically adjustable steering column tubes in a conventional manner. Additionally, an electric adjustment drive for height adjustment can be provided, which is inserted in a conventional manner between a steering column or adjusting unit and a body-side support unit.

[0050] Description of the drawings

[0051] Advantageous embodiments of the invention are explained in more detail below with reference to the drawings. In detail:

[0052] Figure 1 shows a steering column according to the invention in a schematic perspective view,

[0053] Figure 2 shows a schematic representation of the position values,

[0054] Figure 3 shows a schematic representation of the position values ​​in a second embodiment. Embodiments of the invention

[0055] In the various figures, identical parts are always provided with the same reference symbols and are therefore usually named or mentioned only once.

[0056] Fig. 1 shows a steering column 1 according to the invention. This comprises a casing unit 2 in which a steering spindle 3 is mounted rotatably about a longitudinal axis L. At the rear end section with respect to the direction of travel, facing the driver's position, a fastening section 31 is formed, to which a steering wheel (not shown here) can be fastened.

[0057] The steering column 1 can be designed as a conventional steering column, in which the steering spindle 3 is mechanically coupled to the steerable wheels. Alternatively, the steering column 1 can be designed as a steer-by-wire steering column, in which the steering spindle 3 is not mechanically connected to the wheels to be steered, and a steering input is electronically detected and used to control electric motor-driven steering actuators.

[0058] The casing unit 2 is held in a support unit 4 that can be attached to the body of the vehicle. For this purpose, the support unit 4 can have fastening means 41, for example, fastening holes or the like.

[0059] The steering wheel 32 is adjustable relative to the support unit 4, which is fixed to the body when installed, in the longitudinal direction defined by the longitudinal axis L, as indicated by the double arrow. For height adjustment, the steering wheel 32 is adjustable up or down in a height direction H relative to the support unit 4 transversely to the longitudinal axis L, as also indicated by a double arrow.

[0060] The longitudinal axis L defines a first adjustment direction, and the height direction H a second adjustment direction, which are collectively referred to as the two adjustment directions.

[0061] The steering spindle 3 is mounted in an inner casing 21 for rotation about the longitudinal axis L. For longitudinal adjustment, this inner casing 21 is telescopically received in an outer casing 22 of the casing unit 2 in the direction of the longitudinal axis L.

[0062] For height adjustment, the support unit 4, specifically the outer shell 22, is pivotally mounted in a region close to the body, at the front with respect to the direction of travel, about a pivot axis 42 lying horizontally, transversely to the longitudinal axis L. By pivoting about this pivot axis 42, the steering spindle 3, which is located at the rear end of the driver's side and remote from the body, can be adjusted in the height direction H by means of a steering wheel attached thereto.

[0063] For the motorized longitudinal adjustment, a first adjustment drive 5 is provided, which can be designed, for example, in a manner known per se as a spindle drive and is operatively inserted between the inner casing 21 and the outer casing 22.

[0064] To implement a longitudinally adjustable telescopic arrangement, it is sufficient for the inner casing 21 to be telescopically received in the outer casing 22. Optionally, to create a multiple telescope, an intermediate casing 23 can be provided, which is telescopically received in the outer casing 22 and, in turn, adjustably accommodates the inner casing 21. However, this does not change the fact that the maximum possible adjustment range is determined by the adjustment of the inner casing 21 relative to the outer casing.

[0065] For motorized height adjustment, a second adjustment drive 6 can optionally be provided, which can, for example, also be designed in a manner known per se as a spindle drive and is effectively inserted between the casing unit 2 and the support unit 4 in the height direction.

[0066] In the example shown, a position detection device 7 according to the invention comprises a target element 71, which in the example shown is elongated in the longitudinal direction, ie, in the direction of the longitudinal axis L. It is connected in its front region to the inner casing 21 and extends rearward to a sensor unit 72, which is fixed to the outer casing 22.

[0067] The sensor unit 72 has a first sensor 73 and a second sensor 74, past which the target element 71 moves during adjustment in the longitudinal direction, which indicates the adjustment direction. The sensors 73 and 74 are arranged next to one another transversely to the adjustment direction, thus enabling parallel measurement of the target 71 moving past them during adjustment.

[0068] The target 71 has a first switching element 75, which is shown schematically and is arranged and configured such that it can be detected by the first sensor element 73 as a first switching threshold, but cannot be detected by the second sensor element 74. Furthermore, the target element 71 has a second switching element 76, which is arranged and configured such that it can be detected by the second sensor element 74 as a second switching threshold, but cannot be detected by the first sensor element 73.

[0069] Switching elements 75 and 76 can comprise magnets, for example, and sensor elements 73 and 74 can comprise magnetic sensors, such as Hall sensors or the like. As a result, sensor 73 emits a switching signal when switching element 75 is moved past it during adjustment, and correspondingly, sensor 74 emits a switching signal when switching element 76 is moved past it during adjustment. Alternatively, other measuring methods can also be used, for example, in the form of a light barrier or the like.

[0070] The method according to the invention is explained using the schematic representation in Fig.2.

[0071] The adjustment in the longitudinal direction, the adjustment direction, is possible over an entire adjustment range V. This is made up of a first adjustment range V1, the operating range, which is followed to the front - to the left in Fig. 2 - by a second adjustment range V2, the transition range, which is followed by a third adjustment range V3, the stowage range.

[0072] The first switching element 75 is arranged at the boundary between the first adjustment range V1 and the second adjustment range V2. The second switching element 76 is arranged at the boundary between the second adjustment range V2 and the third adjustment range V3.

[0073] Below the representation of the adjustment ranges, the position values ​​detected by sensor elements 73 and 74 are plotted against the adjustment path V. Position value P1 is detected by the first sensor element 73, and position value P2 is detected by the second sensor element 74. As shown, the detection is digital, with position values ​​P1 and P2 each being able to assume the values ​​"0" or "1."

[0074] During adjustment, the first switching element 75 generates a switching signal in the first sensor element 73, so that during the transition from the first adjustment range V1 to the second adjustment range V2, the position value P1 is switched from "0" to "1," and then remains at "1" during a further adjustment in the adjustment ranges V2 and V3. In the opposite adjustment direction, the position value P1 is reversibly switched from "1" to "0" again during the transition from the second adjustment range V1 to the first adjustment range V2.In parallel, the second switching element 76 generates a switching signal in the second sensor element 74, but only during the transition from the second adjustment range V2 to the third adjustment range V3, whereby the position value P2 is switched from “0” to “1”: In the case of a reverse adjustment, the position value P2 is reversibly switched from “1” to “0” again during the transition from the third adjustment range V3 to the first adjustment range V2, and then remains at “0” in the adjustment ranges V2 and V3.

[0075] For measurement-related reasons, such as the dimensions of magnets used as switching elements 75 and 76, a direction-dependent hysteresis may occur during switching, which is schematically indicated by the arrows along the P1 and P2 curves. The position values ​​P1 and P2 assume the following values:

[0076] The position values ​​(P1, P2) indicate a binary coded set characteristic for each of the adjustment ranges V1, V2, V3, namely for V1: (0,0), V2: (1,0) and V3: (1,1).

[0077] By means of the method according to the invention, as described at the beginning, a particularly reliable and robust detection can be carried out as to which adjustment range V1, V2 or V3 the steering column 1 is located in.

[0078] The design of the steering column 1 and the method can in principle be transferred to the height direction H with the same functional effect.

[0079] This also allows the definition of impermissible adjustment ranges R, which are certain combined height and length ranges that cannot be reached during adjustment, as schematically indicated in Fig. 2 by the hatched area. Figure 3 shows a schematic representation of the position values ​​in a second embodiment. This differs from Figure 2 only in the position values. For measurement-related reasons, for example, due to the dimensions of magnets that can be used as switching elements 75 and 76, a direction-dependent hysteresis can occur during switching, which is schematically indicated by the arrows in the curves of P1 and P2. The position values ​​P1 and P2 assume the following values:

[0080] The position values ​​(P1, P2) indicate a binary coded set characteristic for each of the adjustment ranges V1, V2, V3, namely for V1: (1,1), V2: (0,1) and V3: (0,0).

[0081] List of reference symbols

[0082] 1 steering column

[0083] 2 jacket unit

[0084] 21 inner jacket

[0085] 22 Outer jacket

[0086] 3 steering spindle

[0087] 31 Fastening section

[0088] 4 carrying unit

[0089] 41 Fasteners

[0090] 42 swivel axis

[0091] 43 side panel

[0092] 5 Adjustment drive

[0093] 6 Adjustment drive

[0094] 7 Position detection device

[0095] 71 target element (=target unit)

[0096] 72 Sensor unit

[0097] 73 first sensor element

[0098] 74 second sensor element

[0099] 75 first switching element

[0100] 76 second switching element

[0101] L Longitudinal axis (longitudinal direction)

[0102] H Altitude direction

[0103] V adjustment range

[0104] VI first adjustment range (operating range)

[0105] V2 second adjustment range (transition range)

[0106] V3 third adjustment range (storage range)

[0107] P1 first position value

[0108] P2 second position value

[0109] R inadmissible adjustment range

Claims

PATENT CLAIMS 1. Method for detecting the position of two adjustable components (21, 22) of a steering column (1) for a motor vehicle, which are adjustable relative to one another in an adjustment direction over a plurality of adjustment ranges (V1, V2, V3), wherein the relative position of the components (21, 22) is detected as a position value by a sensor (72) of a position detection device (7), in which a position value (P1, P2) is detected for each of the adjustment ranges (V1, V2, V3) by at least two sensors (73, 74) of the position detection device (7), wherein a clearly distinguishable combination of the at least two position values ​​(P1, P2) of the at least two sensors (73, 74) is assigned to each of the adjustment ranges (V1, V2, V3), characterized in that of the two sensors (73, 74), which are both fixed to one of the components (22), a target element (71) is recorded,which is attached to a component (21) which is adjustable relative thereto and has at least two switching elements (75, 76), each of which is assigned to one of the sensors (73, 74).

2. Method according to claim 1, characterized in that a position value (P1, P2) is recorded digitally and / or analogously.

3. Method according to one of the preceding claims, characterized in that a position value (P1, P2) of a sensor (73, 74) is switched during the transition between adjustment ranges (V1, V2, V3).

4. Method according to one of the preceding claims, characterized in that a position value (P1, P2) is switched by means of a switching element (75, 76).

5. Method according to one of the preceding claims, characterized in that a position value (P1, P2) is stored.

6. Method according to one of the preceding claims, characterized in that at least one of the sensors (73, 74) detects a position value (P1, P2) as an absolute measured value.

7. Method according to one of the preceding claims, characterized in that the components have at least two casing tubes (21, 22) which can be telescoped in a longitudinal direction.

8. Method according to one of the preceding claims, characterized in that the components have a support unit (4) and a casing unit (4) extending in the longitudinal direction, wherein the support unit (4) supports the casing unit (2) adjustably in a height direction (H) transverse to the longitudinal direction.

9. Method according to one of the preceding claims, characterized in that the adjustment areas (V1, V2, V3) comprise a storage area (V3), a transition area (V2) and an operating area (V1).

10. Steering column (1) for a motor vehicle, comprising two components (21, 22) which are adjustable relative to one another in an adjustment direction over a plurality of adjustment ranges (V1, V2, V3)) and a position detection device (7) which has a sensor (72) for determining the relative position of the components (21, 22), wherein the sensor (72) is designed to detect position values ​​(P1, P2) specific for the adjustment ranges (V1, V2, V3), wherein the position detection device (7) has at least two sensors (73, 74), wherein a position value (P1, P2) can be detected by a sensor (73, 74) for each of the adjustment ranges (V1, V2, V3), and wherein the sensors (73, 74) are adapted to the adjustment ranges (V1, V2, V3) in order to (V1, V2, V3) to detect a clearly distinguishable combination of at least two position values ​​(P1, P2), characterized in that at least two sensors (73,74) are fixed to one of the components (22), and a target element (71), which is attached to a component (21) that is adjustable relative thereto, has at least two switching elements (75, 76), each of which is assigned to one of the sensors (73, 74).

11. Steering column according to claim 10, characterized in that a switching element (75, 76) designed to switch a sensor (73, 74) is arranged between two adjustment ranges (V1, V2, V3).

12. Steering column according to one of claims 10 to 11, characterized in that a sensor (73, 74) is connected to a memory device in which a position value (P1, P2) can be stored.

13. Steering column according to one of claims 10 to 12, characterized in that a Sensor (73, 74) is designed to detect an absolute measured value which is assigned to an adjustment range (V1, V2, V3).

14. Steering column according to one of claims 10 to 13, characterized in that a digitization device is provided for digitizing the position values ​​(P1, P2).

15. Steering column according to one of claims 10 to 14, characterized in that the components have at least two jacket tubes (21, 22) which can be telescoped in a longitudinal direction and / or have a support unit (4) and a jacket unit (2) extending in the longitudinal direction, wherein the support unit (4) supports the jacket unit (2) in a direction transverse to the The height direction (H) is adjustable in the longitudinal direction.

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