DE102023127816A1 - Vehicle assembly comprising an electric motor drive device - Google Patents

Abstract

An assembly of a vehicle (7) comprises an electromotive drive device (2-4) for adjusting an adjustment assembly in or on the vehicle (6), wherein the drive device (2-4) has an electric drive motor (20) which can be electrically energized to carry out an adjustment process for adjusting the adjustment assembly, and a sensor device (24) for generating a sensor signal as a function of a drive movement of the drive motor (20). A control device (5) is designed to evaluate a sensor signal from the sensor device (24) in order to incrementally determine a position value indicating the current position of the adjustment assembly during the adjustment process as a function of the sensor signal generated by the sensor device (24). The control device (5) is designed to reset the incremental determination of the position value as a function of a fault in the electrical supply to the control device (5) and/or the sensor device (24) and additionally as a function of a position error characteristic value of the adjustment assembly.

Description

The invention relates to a vehicle assembly according to the preamble of claim 1 and a vehicle seat with such an assembly.

Such an assembly comprises an electromotive drive device for adjusting an adjustment assembly in or on the vehicle and a control device. The drive device has an electric drive motor that can be electrically energized to carry out an adjustment process for adjusting the adjustment assembly. A sensor device serves to generate a sensor signal as a function of a drive movement of the drive motor. The control device is designed to evaluate a sensor signal from the sensor device in order to incrementally determine a position value indicating the current position of the adjustment assembly during the adjustment process as a function of the sensor signal generated by the sensor device. The control device is also designed to reset the incremental determination of the position value as a function of a fault in an electrical supply to the control device and/or the sensor device.

Such an assembly can, for example, be a component of a vehicle seat. With such a vehicle seat, the vehicle seat as a whole can be adjusted longitudinally relative to a vehicle floor via a longitudinal adjustment device. For this purpose, an adjustment gear, for example a spindle gear, is driven by an electric drive motor, thus adjusting the vehicle seat longitudinally, for example along guide rails. Additional drive devices on a vehicle seat can be configured, for example, to adjust the inclination of a backrest portion of the vehicle seat or to adjust the height of the vehicle seat.

In a drive device of the type in question here, position determination is carried out incrementally by evaluating a sensor signal from a sensor device and incrementally increasing or decreasing a position value that indicates the current position of an adjustment assembly during an adjustment process. To generate a sensor signal, the sensor device can, for example, have an arrangement of one or more Hall sensors that generate pulse signals depending on a rotary movement, for example, of a motor shaft of the drive motor. Using such pulse signals, the position value can be incrementally adjusted to determine the position of the adjustment assembly during an adjustment process.

The drive motor is energized to perform an adjustment process for adjusting the adjustment assembly by applying a motor voltage to the drive motor, for example in a controlled manner by the control device, for example as part of pulse width modulation to control the adjustment speed of the drive motor. If there is a fault in the electrical supply, for example to the control device, for example because an electrical supply line is interrupted, a vehicle fuse is triggered, or there is another interruption in the electrical supply, the adjustment process is interrupted. In this case, it can conventionally happen that information about the position of the adjustment assembly at the time of the fault is not available. In addition, the drive motor and the associated adjustment assembly can run down due to mass inertia, so that in the event of a fault in the electrical supply, for example at the control device, the drive device continues to run for at least a certain adjustment distance and the adjustment assembly does not come to an immediate stop.

Because a power supply failure typically makes it impossible to evaluate sensor signals from the drive device, such a drive motor shutdown results in incremental position determination no longer being reliably possible upon resumption of operation. For this reason, the control device is designed to reset the incremental determination of the position value if a power supply failure of the control device and/or the sensor device occurs, so that upon resumption of operation, incremental position determination for controlling an adjustment process is no longer possible.

The process of resetting the incremental position determination when a fault in the electrical supply occurs during an adjustment process is also called “denormalization”.

In order to enable incremental position determination after a disruption in the electrical supply to the control device and/or the sensor device, it may be necessary, for example, to move the adjustment assembly to a predetermined starting position in order to relearn a reference position, based on which the incremental position determination can then be performed. This may require the intervention of a user to move the adjustment assembly to the predetermined starting position by manually actuating the drive device. position, which can be time-consuming and uncomfortable for the user.

The object of the present invention is to provide a vehicle assembly which, in connection with a resetting of the incremental position determination in the event of a fault in an electrical supply of the control device and/or the sensor device, enables greater user comfort.

This object is achieved by an article having the features of claim 1.

Accordingly, the control device is designed to reset the incremental determination of the position value as a function of a fault in the electrical supply of the control device and/or the sensor device and additionally as a function of a position error characteristic value of the adjustment assembly.

The control device is generally designed to detect the occurrence of a fault in the electrical supply to the control device and/or the sensor device during an adjustment process. If, for example, the power supply is interrupted and, in this context, the control device and/or the sensor device fails, this is registered by the control device. Depending on such a fault, the control device resets an incremental determination of the position value of the adjustment module. So that when operation is resumed after the fault in the electrical supply to the control device and/or the sensor device has been rectified, further operation takes place without an incremental determination of the position value and thus without an incremental position determination on the adjustment module.

Resetting the incremental determination of the position value, also referred to as denormalization, can be understood in this case as meaning that no further position determination is performed during further operation. Likewise, resetting can result in a position determination still being performed, but classifying it as invalid and not being used, for example, to control the (further) adjustment process of the adjustment assembly, for example, to provide an anti-pinch function or a soft-stop function.

In order to increase user comfort, the incremental determination of the position value is not always reset when a fault in the electrical supply to the control device and/or the sensor device occurs during an adjustment process, but rather depending on additional factors. The control device is designed to reset the incremental determination of the position value depending on a fault in the electrical supply to the control device and/or the sensor device and additionally depending on a position error characteristic value of the adjustment module. The decision as to whether the incremental position determination should be reset therefore not only takes into account whether or not a fault in the electrical supply to the control device and/or the sensor device occurred during an adjustment process. In addition, a position error characteristic value of the adjustment module is also taken into account, which indicates the estimated position error that occurred on the adjustment module due to the fault in the electrical supply during the adjustment process, in particular due to the drive motor running down after the electrical supply to the control device and/or the sensor device was interrupted.

The control device is preferably designed to store a current position value determined during the incremental position determination in a non-volatile memory. The control device can also store information, for example, about a load condition, an adjustment speed, an adjustment direction, or the like, in the non-volatile memory. If a disruption in the electrical supply to the control device and/or the sensor device occurs during an adjustment process that is currently being performed and, as a result, the drive motor runs down (uncontrolled), the position error characteristic value can be determined based on the information stored in the control device for resuming operation upon restoration of the electrical supply. This can be used to estimate the range within which a position error of the adjustment assembly that has occurred due to the disruption in the electrical supply could lie. The position error characteristic value determined in this way can be taken into account when deciding whether or not the incremental position determination should be reset for the continued operation of the drive device.

The control device is particularly designed to store the position value indicating the current position of the adjustment assembly in a non-volatile memory in the event of a fault in the electrical supply.

The control device may, for example, comprise an energy storage device for For example, a capacitor (e.g., a so-called logic buffer capacitor) that allows the current position value to be stored in a non-volatile memory when a fault in the electrical supply occurs. In addition, information about a load condition, an adjustment speed, or an adjustment direction of the adjustment module can still be stored in the non-volatile memory when a fault occurs.

The control device can, for example, be designed to identify a fault in the electrical supply by measuring the voltage on an electrical supply line connected to the control device, for example at a supply input of the control device.

For example, if it is determined that the position error characteristic value is below a permissible limit, the incremental position determination may not be reset, so that when operation is resumed after the fault in the electrical supply to the control device and/or the sensor device has been rectified, the incremental determination of the position value is continued on the basis of the position value stored in the control device and determined on the basis of the incremental position determination before the fault occurred.

Because this reduces the number of cases in which the incremental position determination is reset, user comfort can be increased. Furthermore, measures to prevent a disruption to the electrical supply of the control device and/or the sensor device can be reduced, which can simplify the design of a drive device.

In one embodiment, the control device is designed to determine the position value indicating the current position of the adjustment assembly based on a stored reference position and a counter value. The counter value can be changed incrementally depending on the sensor signal generated by the sensor device. Based on the sensor signal and the direction of rotation, the counter value is incremented or decremented. The counter value indicates the position with reference to the reference position from which counting is carried out. The reference position can be learned on the adjustment assembly in an initial calibration process (so-called standardization run) and is stored in the control device during normal operation of the drive device.

In one embodiment, the control device is designed to reset the incremental determination of the position value by resetting the stored reference position and/or the counter value and/or classifying the stored reference position and/or the counter value as invalid. For resetting, the reference position and/or the counter value can, for example, be deleted in the control device. In another embodiment, the stored values for the reference position and the counter value can be retained if necessary, but classified as invalid in the control device, so that a position determined via the incremental position determination is no longer used to control an adjustment process after the incremental determination of the position value has been reset.

In one embodiment, the sensor device has at least one Hall sensor for detecting the drive movement of the drive motor. Such a Hall sensor can be arranged in the region of a rotatable part of the drive device, in particular a rotatable part of the drive motor or a gear operatively connected to the drive motor. For example, a magnetic element can be arranged on the rotatable part, which is moved past the Hall sensor due to the rotational movement of the rotatable part in order to generate a pulse signal at the Hall sensor through magnetic interaction with the Hall sensor, which pulse signal can be evaluated to incrementally change a counter value. Depending on a signal generated by one or more Hall sensors, the counter value can be incremented or decremented, taking into account the direction of rotation of the drive motor, in order to determine the position value indicating the current position of the adjustment assembly.

For example, the at least one Hall sensor can be configured to generate the sensor signal as a function of a rotational movement of a motor shaft of the drive motor. The at least one Hall sensor can, for example, assume a position opposite the motor shaft and interact, for example, with a magnetic element arranged on the motor shaft, so that a pulse signal can be generated using the Hall sensor that indicates the rotational movement of the motor shaft.

In one embodiment, the control device is designed to determine the position error characteristic value based on an estimated value for a position error due to a rundown of the drive motor when a fault occurs in the electrical supply of the control device and/or the sensor device. If a fault occurs in the electrical supply during an adjustment process, If the power supply to the control device and/or the sensor device is interrupted, for example, due to an interruption in an electrical supply line or a blown fuse, the drive motor typically runs down over a certain adjustment range due to the inertia of the drive device. The position error characteristic is determined by the control device based on information that the control device acquired and stored before the fault occurred. The position error characteristic corresponds to an estimated value that allows the estimation of a position error of the adjustment module due to overrun after the fault occurs.

In one embodiment, the control device is designed to determine the position error characteristic value as a function of a load state of the adjustment assembly, an adjustment speed of the adjustment assembly, a direction of rotation of the drive motor and/or the position of the adjustment assembly when a fault occurs in the electrical supply of the control device and/or the sensor device.

The load state depends in particular on the weight forces acting on the adjustment assembly, for example due to forces exerted on the adjustment assembly by a user. If the adjustment assembly is a vehicle seat, for example, the load state depends, for example, on whether a user is sitting on the vehicle seat and the weight force the user exerts on the vehicle seat. A load on the adjustment assembly can be determined, for example, via a sensor, for example a weight sensor on the adjustment assembly (e.g. the vehicle seat), an interior sensor, a seat occupancy detector, or the like. The load state particularly influences the mass inertia acting on the adjustment assembly.

The adjustment speed is determined, for example, based on the sensor signal generated by the sensor device for incremental position determination. The current adjustment speed is stored, for example, by the control device, so that even after a malfunction occurs, the adjustment speed present immediately before the malfunction occurred in the adjustment assembly is known and can be evaluated by the control device. The adjustment speed also significantly influences the stopping behavior of the adjustment assembly.

Depending on the direction of rotation, the stopping behavior of the drive motor can change. For example, when adjusting the tilt of a backrest, the stopping behavior may depend on whether the backrest is adjusted from an upright position toward a flattened position or from a flattened position toward an upright position. This can be taken into account when determining the position error characteristic.

The position error characteristic may also depend on the position of the adjustment assembly when the fault occurs in the electrical supply to the control device and/or the sensor device. For example, the stopping behavior of the drive motor may depend on the position the adjustment assembly was in when the fault occurred. If the adjustment assembly is, for example, the backrest of a vehicle seat, the stopping behavior of the drive motor may depend on whether the backrest was in an upright position, in an intermediate position between an upright position and a flattened position, or in a flattened position when the fault occurred.

The position error characteristic can, for example, be an estimated value that indicates the maximum position error. The control device thus estimates the maximum travel distance the drive motor has traveled when the power supply failure occurs, depending on the load condition, the adjustment speed, the direction of rotation, and the position. Depending on the position error characteristic determined in this way, it can be determined whether or not the incremental position determination should be reset when a failure occurs.

In one embodiment, the control device is designed to determine the position error characteristic value as the sum of a current position error characteristic value and a previous position error characteristic value. In the case of a currently occurring fault event, the control device determines a current position error characteristic value, which is obtained, for example, from a load state of the adjustment module, an adjustment speed of the adjustment module, a direction of rotation of the drive motor and/or the position of the adjustment module at the time the current fault occurs. The current position error characteristic value corresponds, for example, to an estimated value that indicates the maximum position error that may have occurred as a result of the current fault. In addition, to determine the position error characteristic value, the control module also takes into account a previous position error characteristic value that was determined during a previous fault event since the last standardization. If one or more fault events have already occurred before the current fault event, then A position error characteristic value was determined from previous fault events. For the fault event that has just occurred, the position error characteristic value is thus calculated as the sum of the current position error characteristic value related to the current fault event and the previous position error characteristic value stored in a non-volatile memory.

To determine the position error characteristic, the amounts of the current position error characteristic and the previous position error characteristic can be summed.

In another embodiment, to determine the position error characteristic value, the current position error characteristic value and the previous position error characteristic value can be summed with a sign, for example depending on the direction of rotation of the drive motor when the respective fault event occurs, so that the individual position error characteristics can be added or subtracted.

The position error characteristic value is thus calculated as an estimate of the maximum position error resulting from all disturbance events since the last normalization.

In one embodiment, the control device is configured to reset the incremental determination of the position value only if the position error characteristic value is greater than a predetermined error limit. If a fault occurs in the electrical supply of the control device and/or the sensor device and the position error characteristic value is greater than a predetermined error limit, the control device resets the incremental position determination so that no further incremental position determination is performed based on previously determined values during subsequent operation. However, if the position error characteristic value is smaller than the predetermined error limit, the incremental position determination is not reset.

The error limit can be set based on the requirements of specific functions of the drive device, for example, and is predetermined. For example, a pinch protection function or a soft-stop function may require a minimum accuracy in position determination, which determines the error limit.

In one embodiment, the control device is designed to increment a fault counter value when a fault occurs in the electrical supply to the control device and/or the sensor device and to take the fault counter value into account in order to reset the incremental determination of the position value. For this purpose, the control device can store the fault counter value in a non-volatile memory. With each occurrence of a fault event in which a fault occurs in the electrical supply to the control device and/or the sensor device, the fault counter value can be incremented by 1, so that the fault counter value indicates the number of fault events that have occurred. Also depending on the fault counter value, the control device decides whether the incremental position determination should be reset if a new fault event occurs.

For example, it can be provided that the control device always resets the incremental position determination when a fault occurs in the electrical supply of the control device and/or the sensor device during an adjustment process if the fault counter value exceeds a predetermined limit value.

In one embodiment, the control device is designed to adapt the position value based on the position error characteristic value when a fault occurs in the electrical supply to the control device and/or the sensor device. If a fault occurs in the electrical supply to the control device and/or the sensor device during an adjustment process and the incremental position determination is not reset, the accuracy of the position determination during further operation can be improved by correcting the position value based on the position error characteristic value determined by the control device when the fault occurs. The position error characteristic value indicates an estimated value for a position error due to overrun of the drive motor. Based on this position error characteristic value, the position value determined during the incremental position determination before the fault occurs can be corrected, so that the accuracy of the position value for the further incremental position determination after operation is resumed can be improved.

In one embodiment, a vehicle seat comprises an assembly of the type described above. The drive device can accordingly be a drive device for adjusting an adjustment assembly of the vehicle seat. The drive device can be, for example, a drive device for a longitudinal adjustment device of a vehicle seat, a tilt adjustment device of a backrest, a height adjustment device, a seat depth adjustment device, or another adjustment device of a vehicle seat.

• 1 eine schematische Ansicht eines Fahrzeugs mit einem darin angeordneten Fahrzeugsitz, umfassend eine Mehrzahl von Antriebsvorrichtungen;
• 2 eine schematische Ansicht eines Ausführungsbeispiels einer Antriebsvorrichtung;
• 3 ein Ablaufschema zum Bestimmen, ob bei Auftreten einer Störung in der elektrischen Versorgung einer Steuereinrichtung und/oder einer Sensoreinrichtung eine inkrementelle Positionsbestimmung zurückgesetzt werden soll;
• 4 eine schematisches Prinzipbild einer Steuereinrichtung;
• 5 eine graphische Darstellung von Spannungsverläufen bei Auftreten einer Störung in der elektrischen Versorgung.

The concept underlying the invention will be explained in more detail below with reference to the exemplary embodiments illustrated in the figures. They show:

• 1 a schematic view of a vehicle with a vehicle seat arranged therein, comprising a plurality of drive devices;
• 2 a schematic view of an embodiment of a drive device;
• 3 a flow chart for determining whether an incremental position determination should be reset in the event of a fault in the electrical supply of a control device and/or a sensor device;
• 4 a schematic diagram of a control device;
• 5 a graphical representation of voltage curves when a fault occurs in the electrical supply.

1 shows a schematic view of a vehicle 7 with a vehicle seat 1 arranged therein, which has a seat part 10 and a backrest part 11 whose inclination can be adjusted relative to the seat part 10. A plurality of vehicle seats 1 are usually arranged in a vehicle 7, for example two front vehicle seats, several individual vehicle seats or a continuous bench seat in a second row of seats, and optionally additionally further vehicle seats in a third row of seats.

The 1 The vehicle seat 1 shown by way of example is longitudinally adjustable in the vehicle 7 via a longitudinal adjustment device 13. For this purpose, upper guide rails 131, which are assigned to the vehicle seat 1, are guided longitudinally on floor-side, lower guide rails 130. The vehicle seat 1 is connected to the upper guide rails 131 via a height adjustment device 12. The vehicle seat 1 is height-adjustable relative to a vehicle floor via the height adjustment device 12. Pivoting elements 120, 121, which are articulated on the one hand to the arrangement of upper guide rails 131 and also articulated to a seat frame of the seat part 10, can be pivoted to adjust the height position in order to lower or raise the seat part 10 with the backrest part 11 arranged thereon relative to the vehicle floor.

The vehicle seat 1 can have a plurality of electromotive drive devices 2, 3, 4, each of which is assigned to an adjustment device, namely, for example, the longitudinal adjustment device 13 (drive device 2), the height adjustment device 12 (drive device 3), and a backrest inclination adjustment device for adjusting the inclination of the backrest part 11 (drive device 4). A control device 5 serves to control the drive devices 2, 3, 4, wherein each drive device 2, 3, 4 can have its own dedicated control, or the vehicle seat 1 can have a uniform control device for controlling the different drive devices 2, 3, 4. It is also possible for a central control device to be provided in the vehicle 7, which (also) controls the drive devices 2, 3, 4 of the vehicle seat 1.

It should be noted that the presently described embodiment is directed to a drive device for adjusting an adjustment assembly of a vehicle seat 1, but this is not to be understood as limiting in any way. A drive device can also be used to adjust another adjustment assembly in a vehicle 7, for example, to adjust a console element, a table assembly, a flap element, or another assembly in the vehicle 7.

For example, for longitudinal adjustment of the vehicle seat 1, a drive device 2 associated with the longitudinal adjustment device 13 may have a spindle gear to effect a relative movement between pairs of guide rails 130, 131. As shown schematically in 2 As shown, such a drive device 2 can have a drive motor 20 with a rotatable, driven motor shaft 200, which carries a drive element in the form of a drive worm 21. The drive worm 21 is in meshing connection with a spindle nut 22, which in turn is threadedly engaged with a spindle 23. The drive motor 20 is arranged, for example, together with the spindle nut 22 in a stationary manner on an upper guide rail 131, while the spindle 23 is arranged stationary on a lower guide rail 130. During operation, the drive motor 20 drives the spindle nut 22 via the drive worm 21 and sets it in a rotary movement such that the spindle nut 22 rolls on the spindle 23 due to the threaded engagement and is thus adjusted longitudinally relative to the spindle 23. In this way, a longitudinal movement along the spindle 23 and thus a relative movement between the guide rails 130, 131 is effected for the longitudinal adjustment of the vehicle seat 1.

An adjustment process driven by the drive motor 20 of the drive device 2 is controlled by the control device 5. For this purpose, a voltage provided by an electrical supply system 6 of the vehicle 7 is The motor voltage provided is applied to the drive motor 20, and the drive motor 20 is energized via this voltage. To control the drive motor 20, pulse width modulation can be used, for example, whereby the drive motor 20 can be operated, for example, in a current-controlled or voltage-controlled manner via the control device 5.

Control via control device 5 is generally performed in a position-controlled manner, for example, to implement a so-called soft-stop function upon automatic adjustment to a defined position of an associated adjustment assembly or to provide position-dependent anti-pinch protection. The position of the associated adjustment assembly is determined incrementally by detecting a movement of the motor shaft 200 of the drive motor 20 via a sensor device 24, for example, comprising one or more Hall sensors, and incrementally increasing or decreasing a position value indicating the position of the associated adjustment assembly based on a pulse signal generated by the sensor device 24.

Incremental position determination is preferably performed by incrementally counting or decrementing a counter value starting from a reference position. A position value indicating the position of the associated adjustment assembly is thus derived from the counter value with reference to the reference position, with the counter value indicating the position relative to the known reference position.

The reference position is typically read in during a calibration process, for example, by moving the adjustment assembly, such as the vehicle seat 1, to a predetermined position, e.g., an end position during a longitudinal adjustment, and initializing the counter value. During subsequent operation, the position value indicating the current position of the adjustment assembly is then determined incrementally with reference to the learned reference position.

However, if during operation, a disruption in the electrical supply to the control device 5 and/or the sensor device 24 occurs during an adjustment process being performed by the drive device 2, for example because a fault occurs in the electrical supply system 6 of the vehicle 7 (for example, due to a loose contact or due to a blown fuse), thus interrupting the control and thus the operation of the drive motor 20, incremental position determination after the electrical supply is restored may be subject to inaccuracies. This is due to the fact that if the motor voltage drops during an ongoing adjustment process, the drive motor 20 does not stop immediately, but rather, due to the inertia of the mass, in particular of the associated adjustment assembly, coasts down over a certain distance until the drive motor 20 comes to rest. Due to such coasting behavior, the position value last determined before the disruption occurred (corresponding to the counter value with reference to the known reference position) no longer automatically corresponds to the actual position of the adjustment assembly.

For this reason, the control device 5 is configured to perform a so-called denormalization of the incremental position determination if a fault occurs in the electrical supply to the control device 5 and/or the sensor device 24 during an ongoing adjustment process. During the denormalization process, the position value is reset by deleting it or classifying it as invalid, so that no incremental position determination takes place when operation resumes after the electrical supply is restored.

Such a resetting of the incremental position determination requires that the reference position be re-taught for resuming operation. This requires that the adjustment assembly be adjusted to a defined position corresponding to the reference position, for example, an end position, by manually actuating the drive device 2 by a user in order to re-standardize the incremental position determination. So that during further operation, a counter value can then be incrementally counted up or down with reference to the now again standardized, known reference position, and thus a position value can be determined that indicates the current position of the assigned adjustment assembly.

Because such re-standardization requires user intervention, it can be time-consuming and uncomfortable for a user and may be difficult to implement (especially if the user is non-expert).

For this reason, it is proposed here not to always reset the incremental position determination when a disturbance in the power supply of the control device 5 and/or the sensor device 24 occurs during an adjustment process. Rather, the control device 5 is designed to reset the incremental determination of the position value depending on a disturbance in the electrical supply of the control device 5 and/or the sensor device 24 and additionally in Dependence on a position error characteristic of the adjustment module.

The position error characteristic value can be determined, in particular, based on an estimated value that indicates an estimated adjustment path that the drive motor 20 will still travel after the electrical power supply is interrupted, in particular due to the inertia of the adjustment assembly. The position error characteristic value should therefore, in particular, indicate an estimated position error that results from the drive motor 20 and the associated adjustment assembly stopping after a disruption in the electrical supply during an adjustment process.

The position error characteristic value can, for example, indicate an estimated value for the maximum position error occurring when coasting down in the system of the drive motor 20 and the associated adjustment assembly.

To calculate the position error characteristic value, the control device 5 can in particular include a load state of the adjustment assembly, an adjustment speed of the adjustment assembly when the fault occurs in the electrical supply of the control device 5 and/or the sensor device 24, a direction of rotation of the drive motor 20 when the fault occurs and/or the position of the adjustment assembly when the fault occurs in the electrical supply of the control device 5 and/or the sensor device 24.

If the adjustment assembly is, for example, a vehicle seat 1, the rundown after a fault occurs in the electrical supply to the control device 5 and/or the sensor device 24 will depend, for example, on whether a user is sitting on the vehicle seat 1 or not and the weight force exerted on the vehicle seat 1. A load state can thus be determined, for example, by determining an occupancy state of the vehicle seat 1, for example via an occupancy sensor or an interior sensor system. In addition, a weight force on the adjustment assembly, for example on the seat part 10 of the vehicle seat 1, can be determined by a weight sensor system, for example a weight sensor in the seat part 10, in order to estimate an inertial force on the adjustment assembly.

The stopping behavior is also influenced by the adjustment speed when the fault occurs. For this purpose, the last stored speed value can be taken into account by the control device 5.

Likewise, the stopping behavior may depend on the position and direction of movement of the adjustment assembly when the fault occurs. For example, a tilt adjustment may have a different stopping behavior depending on whether the backrest part 11 is in an upright or a flattened position and whether the backrest part 11 is being lowered or raised.

A typical run-out behavior can, for example, be measured initially in a calibration routine before commissioning of a drive device 2, 3, 4 and stored, for example, in a characteristic map in the form of a matrix in a memory of the control device 5, in which position error characteristic values are stored as a function of a load condition, an adjustment speed, a direction of rotation and a position of the adjustment assembly.

A previous position error value can also be taken into account when determining the position error value. This means that the position error value can be determined as the sum of the current position error value and a previous position error value. The current position error value is determined for the current fault event, for example, depending on a load condition, an adjustment speed, an adjustment direction, and an adjustment position of the adjustment module when the current fault event occurs. If one or more previous fault events have already occurred (after a nomination), position error values have also been determined for these fault events. For the current fault event, the position error value is then determined based on the sum of the current position error value and a previously determined position error value, so that the position error values of the fault events are added together.

To determine the position error characteristic value, the amounts of the individual position error characteristics can be added together.

In another embodiment, the individual position error values can be considered with a sign. Thus, depending on the direction of rotation of the drive motor 20 when a fault occurs, a position error value can be assigned a sign that indicates the direction in which the drive motor 20 coasted when the fault occurred. The current position error value and the previous position error value can thus be added or subtracted with a sign.

In order to determine whether the incremental position determination should be reset when a fault occurs, the control device 5 checks the position error characteristic value which results depending on the adjustment process carried out.

For example, the control device 5 checks whether the determined position error characteristic value is greater than an error limit. If this is the case, the control device 5 resets the incremental position determination, so that no incremental position determination takes place during further operation when the electrical supply to the drive motor 20 is restored. If, on the other hand, the position error characteristic value is smaller than the error limit, the incremental position determination is not reset, and when operation is resumed and the electrical supply is restored, the incremental position determination continues with the same standardization, i.e., the same reference position, as before the fault occurred.

To improve the accuracy of incremental position determination after a fault occurs without resetting the incremental position determination, a position value determined from the reference position and the error value can be corrected using the position error characteristic. For example, the counter value can be corrected using the determined position error characteristic so that the stopping behavior after the fault occurs is taken into account in the further incremental position determination after operation resumes.

In addition, the control device 5 can also take into account how many fault events have already occurred in total when deciding whether or not to reset the incremental position determination. For example, the control device 5 can store a fault counter value (in a non-volatile memory) which is incremented by 1 whenever a fault occurs. The fault counter value thus indicates the total number of faults that have occurred after normalizing the incremental position determination. The fault counter value can be taken into account when deciding whether to reset the incremental position determination, for example by checking whether the fault counter value is above a limit value and thus more than a defined number of faults have already occurred. If this is the case, the control device 5 can reset the incremental position determination, for example, independently of a determined position error characteristic value.

3 shows a schematic flow diagram of a method carried out by the control device 5 for resetting the incremental position determination.

In a step S1, the control device 5 determines that a fault in the electrical supply of the control device 5 and/or the sensor device 24 has occurred during an adjustment process.

If such a fault has occurred, a position error characteristic value is determined in a step S2, wherein the position error characteristic value is estimated, for example, taking into account a load condition, an adjustment speed, an adjustment direction and a position (in each case when the fault occurs) of the adjustment assembly by estimating a resulting run-out path from which the position error characteristic value is derived.

In step S3, a check is performed to determine whether the position error characteristic is greater than a predetermined error limit. If this is the case, the incremental position determination is reset in step S4. Thus, an incremental position determination upon resumption of operation can only be performed after the incremental position determination has been normalized again.

However, if the position error characteristic is smaller than the error limit, a check is performed in step S5 to determine whether the error counter value is greater than a limit. If this is the case, the incremental position determination is reset in step S6.

However, if this is not the case, the incremental position determination is not reset in step S7, so that after resuming operation after the electrical supply to the drive motor 20 is restored, the incremental position determination is continued with the previously applicable standardization.

4 shows a schematic diagram of an embodiment of a control device 5, which is connected to an electrical supply system 6 of the vehicle, for example, a vehicle battery, via an electrical supply line 60. The drive motor 20 of the adjustment device 2 is controlled and supplied with electrical power via the control device 5, so that the drive motor 20 is energized in a controlled manner during operation, for example, using pulse width modulation.

The control device 5 has a logic circuit 50 and a power circuit 51. Both the logic circuit 50 and the power circuit 51 are connected to the electrical supply line 60 connected to a supply input 52 of the control device 5 and are supplied with electrical energy via the electrical supply line 60 during operation.

The power circuit 51 has a reverse polarity protection circuit 510, for example, configured with an array of MOSFET transistors, a filter circuit 511, which may, for example, have an intermediate circuit capacitance, and a bridge circuit 512, for example in the form of a B6 bridge. The drive motor 20 of the adjustment device 2 is supplied with electrical power via the power circuit 51, in particular by applying a motor voltage to the drive motor 20 and setting a motor current, for example, as part of a current control.

The logic circuit 50 has a microcontroller 502 which performs electronic control tasks, in particular for controlling the motor 20. The microcontroller 502 is connected to the sensor device 24 and in particular carries out a routine for the incremental position determination in order to control the drive motor 20 based on the position determination.

The logic circuit 50 further comprises a diode 500 and an energy storage device 501, for example in the form of a capacitor (so-called logic buffer capacitor). The energy storage device 501 is charged with energy from the electrical supply line 60 via the diode 500, so that after a disruption in the electrical supply, electrical energy is buffered in the energy storage device 501, which at least enables a proper shutdown of the control device 5. The diode 500 prevents the stored energy from being fed back to the supply system 6.

During operation, the microcontroller 502 of the control device 5 controls the drive motor 20. A motor voltage is applied to the drive motor 20 via the power circuit 51, thereby supplying the drive motor 20 with electrical power. If a fault event E occurs in the electrical supply, for example, due to a break or a loose connection on the supply line 60 or if a fuse blows, the electrical supply to the control device 5 and thus also the electrical supply to the drive motor 20 is interrupted.

The control device 5 is designed to detect such an interruption in the electrical supply, for example, by measuring an input voltage at the supply input 52. If the input voltage drops, it is concluded that there is a fault in the electrical supply.

5 shows an example of possible voltage curves (over time) when a fault occurs in the electrical supply, for example on supply line 60.

If a fault occurs in the electrical supply, the supply voltage UV at the supply input 52 of the control device 5 drops. If the supply voltage UV falls below a predetermined threshold, for example, a fault event E is identified at a time T1.

If the electrical supply to the control device 5 is interrupted, the drive motor 20 is also no longer supplied with electricity via the power circuit 51. Accordingly, the motor voltage UM drops. For example, after detecting a fault in the electrical supply at time T1, the current supply to the drive motor 20 is terminated at time T2.

Due to the energy stored in the energy storage device 501, the microcontroller 502 of the control device 5 can continue to operate via the voltage UL provided by the energy storage device 501, at least for a certain period of time.

In particular, using the energy stored in the energy storage device 501 of the control device 5, the instantaneous position value, which indicates the current position of the adjustment assembly at the time the fault occurs, can be stored in a non-volatile memory at time T3. In addition, information about an adjustment speed, a load, and an adjustment direction on the adjustment assembly at the time the fault occurs can also be stored in the non-volatile memory of the microcontroller 502.

At time T4, when the voltage UL at the energy storage device 501 drops, the microcontroller 502 is shut down in a controlled manner. The control device 5 is thus switched off.

If the electrical supply is restored, the position value stored at the time the fault occurred is used and, using the stored information, information, a position error characteristic value is determined which indicates a follow-up behavior of the drive motor 20 when the fault occurs in order to determine whether a reset of the incremental position determination is necessary or not and, if necessary, to correct the position value for a subsequent incremental position determination (without resetting), as described above.

The idea underlying the invention is not limited to the embodiments described above, but can also be implemented in other ways.

A drive device can be used to adjust a wide variety of adjustment assemblies in a vehicle and is therefore not limited to use on a vehicle seat. A drive device of the type described here can generally be used to adjust any interior assembly, for example, a console element, a flap element, a storage device, a display device, or the like.

List of reference symbols

1

vehicle seat

10

Seat part

11

Backrest part

12

Height adjustment device

120, 121

Swivel elements

13

Longitudinal adjustment device

130, 131

Guide rails

2

adjustment device

20

Electric drive motor

200

Motor shaft

21

Drive worm

22

spindle nut

23

spindle

24

Sensor device (Hall sensor)

3

adjustment device

4

adjustment device

5

Control device

50

Logic circuit

500

diode

501

Energy storage device

502

Microcontroller

51

Power circuit

510

Reverse polarity protection circuit

511

Filter circuit

512

Bridge circuit

52

Supply input

6

Electrical supply system

60

supply line

7

vehicle

E

Disturbance

S1-S7

Steps

UL

Voltage to microcontroller

UM

Motor voltage

UV

Supply voltage

Claims (14)

A vehicle assembly (7), comprising an electromotive drive device (2-4) for adjusting an adjustment assembly in or on the vehicle (6), wherein the drive device (2-4) has an electric drive motor (20) which can be electrically energized to carry out an adjustment process for adjusting the adjustment assembly, and a sensor device (24) for generating a sensor signal as a function of a drive movement of the drive motor (20), and a control device (5) which is designed to evaluate a sensor signal of the sensor device (24) in order to incrementally determine a position value indicating the current position of the adjustment assembly during the adjustment process as a function of the sensor signal generated by the sensor device (24), wherein the control device (5) is designed to reset the incremental determination of the position value as a function of a fault in an electrical supply of the control device (5) and/or the sensor device (24), characterized in that the control device (5) is designed to reset the incremental determination of the position value in Depending on a fault in the electrical supply of the control device (5) and/or the sensor device (24) and additionally depending on a position error characteristic value of the adjustment assembly. Assembly according to Claim 1 , characterized in that the control device is designed to store the position value indicating the current position of the adjustment assembly when a fault in the electrical supply occurs. Assembly according to Claim 1 or 2 , characterized in that the control device (5) an energy storage device (500) for providing electrical energy when a fault in the electrical supply occurs. Assembly according to one of the Claims 1 until 3 , characterized in that the control device (5) is designed to determine the position value indicating the current position of the adjustment assembly on the basis of a stored reference position and a counter value, wherein the counter value is incrementally variable depending on the sensor signal generated by the sensor device (24). Assembly according to Claim 4 , characterized in that the control device (5) is designed to reset the stored reference position and/or the counter value and/or to classify the stored reference position and/or the counter value as invalid in order to reset the incremental determination of the position value. Assembly according to one of the preceding claims, characterized in that the sensor device (24) has at least one Hall sensor for detecting the drive movement of the drive motor (20). Assembly according to Claim 6 , characterized in that the at least one Hall sensor is designed to generate the sensor signal as a function of a rotational movement of a motor shaft (200) of the drive motor (20). Assembly according to one of the preceding claims, characterized in that the control device (5) is designed to determine the position error characteristic value on the basis of an estimated value for a position error due to a rundown of the drive motor (20) when a fault occurs in the electrical supply of the control device (5) and/or the sensor device (24). Assembly according to one of the preceding claims, characterized in that the control device (5) is designed to determine the position error characteristic value as a function of a load state of the adjustment assembly, an adjustment speed of the adjustment assembly, a direction of rotation of the drive motor (20) and/or the position of the adjustment assembly when a fault occurs in the electrical supply of the control device (5) and/or the sensor device (24). Assembly according to one of the preceding claims, characterized in that the control device (5) is designed to determine the position error characteristic value as the sum of a current position error characteristic value and a previous position error characteristic value. Assembly according to one of the preceding claims, characterized in that the control device (5) is designed to reset the incremental determination of the position value only if the position error characteristic value is greater than a predetermined error limit value. Assembly according to one of the preceding claims, characterized in that the control device (5) is designed to increase a fault counter value when a fault occurs in the electrical supply of the control device (5) and/or the sensor device (24) and to take the fault counter value into account in order to reset the incremental determination of the position value. Assembly according to one of the preceding claims, characterized in that the control device (5) is designed to adapt the position value on the basis of the position error characteristic value in the event of a fault in the electrical supply of the control device (5) and/or the sensor device (24). Vehicle seat (1), with an assembly according to one of the preceding claims.

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