Vehicle seat with weight detection at a plurality of adjustment speeds

Abstract

The proposed solution relates to a vehicle seat (1) comprising: a seat part assembly (10), a backrest assembly (11), a floor assembly (13) which supports at least the seat part assembly (10), an adjustment apparatus (12) for adjustment of the seat part assembly (10) and / or the backrest assembly (11) relative to the floor assembly (13) by means of a drive device (3), and a control system (14) which is coupled to the drive device (3) and is configured to carry out the following steps: reading in a target value indicating an adjustment speed and / or a rotational speed; and carrying out a weight measurement with the target value which has been read in, by: activating the drive device (3) in order to bring about an adjustment of the seat part assembly (10) and / or of the backrest assembly (11) relative to the floor assembly (13) according to the target value; detecting at least one value of a parameter of the adjustment apparatus (12) and / or of the drive device (3) during the adjustment; and determining a weight acting on the vehicle seat (1) on the basis of the at least one value of the parameter detected during the adjustment, wherein the control system (14) is designed to carry out weight measurements with different target values.

Description

[0001] Brose Fahrzeugteile SE & Co.

[0002] Limited partnership, Coburg

[0003] Max-Brose-Str. 1

[0004] 96450 Coburg

[0005] Vehicle seat with weight detection at multiple adjustment speeds

[0006] Description

[0007] The proposed solution involves a vehicle seat, a process, a corresponding computer program product, and a non-volatile, computer-readable storage medium.

[0008] Several functions in modern vehicles rely on seat occupancy detection. If a vehicle seat is occupied, the vehicle's control units regularly check whether the corresponding seat belt is fastened. Furthermore, airbag deployment can be linked to seat occupancy. In some cases, these and other functions can be improved by not only detecting whether the vehicle seat is occupied in any way, but also by quantifying the weight acting on the seat. For example, an alarm for an unfastened seat belt can be omitted if the vehicle seat is occupied by an object (e.g., a bag) but not by a passenger. Airbag deployment can also be adjusted to the passenger's weight to achieve optimized restraint.

[0009] In practice, for example, so-called Biadder mats or piezo elements can be embedded in a seat component to detect seat occupancy and provide an approximate weight measurement. 2024 179 P

[0010] to carry out page 2. However, such components require installation space and make manufacturing complex, partly due to the additional wiring.

[0011] DE 10 2006 061 669 A1 describes a method for determining the occupancy weight of a vehicle seat, wherein a seat element of the vehicle seat is adjustable by means of a drive unit, comprising the following steps: providing at least one measurement signal representing a state of the drive unit; controlling the drive unit for at least a predetermined duration; during the control period, acquiring the measurement signal; determining a load torque from the measurement signal according to a motor model; and determining the occupancy weight of the seat element as a function of the load torque. An electric drive unit may be provided for adjusting the seat height. However, it has been shown that the accuracy of the measurement could be improved.

[0012] DE 10 2017 217 331 A1 describes a method for operating an electromechanical massage device of a seat, in particular of a motor vehicle, which includes a massage drive with an electric motor, in which the electric motor is energized, a torque of the electric motor is detected and a reference value is determined from this, and on the basis of the reference value an occupancy of at least one section of the seat is determined.

[0013] DE 103 35 734 A1 relates to a method for seat occupancy detection in a motor vehicle with at least one actuator for seat adjustment. The electrical power supply to the actuator(s) for seat adjustment is recorded during their operation and evaluated as a measure of seat occupancy. However, the accuracy of this measurement also has potential for improvement.

[0014] The task is to improve weight measurement in vehicle seats.

[0015] This problem is solved by an object having the features of claim 1.

[0016] A vehicle seat then comprises a seat assembly, a backrest assembly, a base assembly supporting at least the seat assembly, and an adjustment device for adjusting the seat assembly and / or the backrest assembly relative to the base assembly, with a drive device. The vehicle seat further comprises a control system coupled to the drive device, configured to perform the following steps: reading a setpoint that determines an adjustment speed and / or 2024 179 P

[0017] Page 3 specifies a rotational speed; and performing a weight measurement with the input setpoint by the following steps: activating the drive device to effect an adjustment of the seat assembly and / or the backrest assembly relative to the floor assembly according to the setpoint; detecting at least one value of a parameter of the adjustment device and / or the drive device during the adjustment; and determining a weight acting on the vehicle seat based on the at least one value of the parameter detected during the adjustment, wherein the control system is configured to perform weight measurements with different setpoints.

[0018] This is based on the understanding that under different conditions, such as ambient temperature, the magnitude of the applied weight, etc., different adjustment speeds (and corresponding rotational speeds) can yield the best measurement results. Furthermore, it has been shown that by performing measurements sequentially at different adjustment speeds, errors can be detected and improved measurement accuracy achieved. Additionally, interfering effects can have different impacts at different rotational speeds, thus enabling increased accuracy in the manner described. Therefore, by configuring the control system to perform the activation, detection, and determination steps in multiple passes based on different target values, the weight detection by the vehicle seat can be significantly improved.Reading the setpoint can include receiving a target value provided to the control system from the outside and / or determining a target value internally by the control system, e.g. based on given input values.

[0019] The drive unit can be activated at different adjustment speeds. The control system is configured, for example, to signal an adjustment speed to the drive unit. Furthermore, the drive unit can have a maximum adjustment speed. For instance, the drive unit operates at its maximum speed when an adjustment is made, such as when the seat height is set. Specifically, the adjustment speed can be less than or equal to 50% of the maximum speed, optionally less than or equal to 10% of the maximum speed, or even less than or equal to 1% of the maximum speed, so that the adjustment is barely perceptible. This ensures that the weight measurement process is not disruptive to the seat user.If the drive device has a minimum operating speed, the control system can be configured to activate the drive device for weight measurement at this minimum operating speed. 2024 179 P.

[0020] Page 4

[0021] For example, the input setpoint is a first setpoint. The control system can be configured to input a second setpoint along with the first. Alternatively or additionally, the control system can be configured to first input the first setpoint (then, for example, perform a weight measurement or at least activate the drive device once) and then input the second setpoint at a later time. With the two setpoints, which differ from each other, for example, by at least 10%, two different measurements can be taken to achieve improved measurement accuracy overall.

[0022] The control system can be configured to perform the activation, acquisition, and / or determination steps with the first setpoint and then (e.g., immediately afterward or with a time interval) perform the activation, acquisition, and / or determination steps with the second setpoint. For example, the control system is configured to perform the activation, acquisition, and determination steps with the first setpoint and then perform the activation, acquisition, and determination steps with the second setpoint.

[0023] According to a further developed version, the control system is configured to compare, calculate, and / or average the weight determined using the first target value and the weight determined using the second target value. Such a comparison allows measurement errors to be detected, for example, in the case of a deviation that is larger than expected. Furthermore, improved accuracy can be achieved through calculation, such as averaging.

[0024] For example, the control system is designed to determine the weight acting on the vehicle seat based on the difference between the parameter value recorded during the first adjustment with the first setpoint and the parameter value recorded during the second adjustment with the second setpoint. This is because it has been shown that, for example, the current difference at different speeds can be dependent on the load. This allows for a simplified measurement without a load test (e.g., only one measurement at 2000 RPM and one at 4000 RPM). The load can then be determined solely from the difference between the two measurements.

[0025] The control system can include a storage medium in which the setpoints (or at least one of the setpoints) are stored. Alternatively or additionally, the 2024 179 P

[0026] Page 5

[0027] The control system includes an interface, for example, for communication with another device. The control system is configured, for instance, to read the setpoints (or at least one of the setpoints) from the storage medium and / or can be configured to receive the setpoints (or at least one of the setpoints) via the interface. Alternatively or additionally, the control unit can be configured to calculate the setpoint(s). This enables fast processing of optimized setpoints.

[0028] The control system can be configured to read the target value or values ​​based on a weight acting on the vehicle seat that has already been determined previously and / or by other means. This allows the measurement to be performed at the adjustment speed that provides the highest accuracy for the given weight.

[0029] The control system is configured, for example, to read a smaller target value when a larger, previously determined weight is applied to the vehicle seat than when a smaller, previously determined weight is applied. The larger and smaller weights are relative to each other, and the smaller and larger target values ​​are also relative. For instance, the value of the read target value is inversely proportional to the value of the previously and / or otherwise determined weight. A first weight that is smaller than a second weight thus results in a target value that is larger than the target value derived from the second weight. To give a possible example, the target value SW can be determined by calculating an equation that incorporates the previously / otherwise determined weight, for example, SW = a - bx, where x is the weight and a and b are constants.Alternatively or additionally, the target value can be limited to a range above a predefined or predefinable minimum value and / or to a range below a predefined or predefinable maximum value. Of course, entirely different equations are also possible. With a low load, a higher speed allows for a more accurate measurement; with a high load, a lower speed allows for a more accurate measurement.

[0030] In one embodiment, the control system is configured to read the setpoint based on a temperature, for example, the ambient temperature of the vehicle seat, e.g., the temperature inside the vehicle containing the seat. Furthermore, the temperature can be the temperature of the drive device, in particular the drive motor of the drive device. 2024 179 P

[0031] Page 6

[0032] The vehicle seat can either have an integrated temperature sensor or receive data from an external temperature sensor. At low temperatures, the adjustment current can increase. At reduced speeds, the phase voltage can be lower, thus providing a greater control reserve.

[0033] Furthermore, the control system can be configured to detect a measurement accuracy requirement and read the setpoint based on that required accuracy. High measurement accuracy can be achieved with a lower adjustment speed, so that, for example, a setpoint corresponding to a low adjustment speed is read when high accuracy is required. Conversely, if a fast measurement is required where accuracy is less critical, a setpoint corresponding to a high adjustment speed can be read, resulting in lower measurement accuracy. This allows for optimized measurement depending on the specific requirements.

[0034] The control system can be configured to activate the drive device in such a way that a larger adjustment range occurs when a higher setpoint is reached than when a lower setpoint is reached. This allows, for example, high measurement accuracy to be achieved even with different setpoints, if required.

[0035] The parameter can be an electrical parameter, in particular a current, voltage, or power. Alternatively or additionally, the parameter can specify a torque. Alternatively or additionally, the parameter can specify a rotational speed (e.g., of the drive device), in particular the maximum speed reached during adjustment. These parameters allow for easy conversion to a weight, e.g., using a conversion formula and / or a lookup table (LUT). The parameter can relate to one or more drive motors of the drive device. Optionally, the control system is configured (for each of the two directions) to measure the voltage and / or current of the drive device starting from a base value (e.g.,The value (zero) is increased until a component of the height adjustment device, in particular a drive motor of the drive unit, is set in motion from a standstill. The parameter value is then, for example, the achieved current or voltage. The control system can also be configured to stop the drive unit as soon as it registers the movement. This allows weight measurement to be achieved with only minimal movement. The adjustment in the first and second directions is therefore minimal and hardly noticeable, if at all, to a seated user. 2024 179 P.

[0036] Page 7

[0037] Alternatively (or additionally), the parameter (or another parameter) can specify an adjustment path traveled within a certain (especially predetermined) time, in particular the length of this adjustment path, or an adjustment time required for a certain (especially predetermined) adjustment path. These parameters also allow for easy conversion into a weight, e.g., using a conversion rule and / or a LUT (Load Utilization Table).

[0038] The adjustment device can be a height adjustment device for adjusting the distance between the seat assembly and the base assembly. The control system can be configured to activate the drive device for adjusting the distance between the seat assembly and the base assembly in one direction. This allows for particularly accurate weight measurements.

[0039] The direction can be a first direction, and the control system can further be configured to perform the following steps (e.g., after the activation and sensing steps with respect to the first direction): activating the drive device to adjust the distance between the seat assembly and the floor assembly in a second direction opposite to the first; and sensing a value of the parameter of the height adjustment device and / or the drive device during the adjustment in the second direction. The control system can also be configured to determine a weight acting on the seat assembly based on the sensed parameter values ​​from the adjustments in both directions. This is based on the idea that a height adjustment motor generates a torque during the adjustment, which corresponds to a current.This current can be measured via the control system (which may include electronics located at the vehicle seat and / or a central vehicle control unit) and used to evaluate the load increase. Furthermore, the described solution is based on the understanding that friction and tolerances can affect the accuracy of weight measurement, but that measuring in both adjustment directions allows such influences to be compensated for. Thus, a particularly precise weight determination can be achieved with a very simple setup.

[0040] The control system can be configured to move the drive device in the first direction and in the second direction for a predetermined time and / or over a predetermined adjustment range (e.g., measured by the number of motor rotations).

[0041] Activate page 8. This allows, for example, the power output to be determined via the predetermined adjustment range or the predetermined adjustment time and used to determine the weight.

[0042] The control system can include a storage medium containing, for example, a model that assigns a corresponding value of an applied weight to each parameter value, specifically to each possible parameter value. Using this model (e.g., in the form of a learning load table), the weight can be determined in a particularly simple manner. The model can also be a machine learning model that has been trained, for example, with various weight loads. Optionally, the model assigns a value of an applied weight to each parameter value (specifically, each possible parameter value) for several possible settings of the height adjustment device. This takes into account that, due to the kinematics of the height adjustment device, the same torque is not required for adjustment in every setting.

[0043] Optionally, the model assigns a value for an acting weight to each parameter value (specifically, each possible value of the parameter) with respect to an adjustment in the first direction on the one hand, and with respect to an adjustment in the second direction on the other (independently of each other). This further improves the accuracy of the measurement. For example, the control system is configured to determine the acting weight separately based on the measured parameter value for the first direction and based on the measured parameter value for the second direction. Optionally, the control system is also configured to calculate the weight acting on the seat assembly from these two weight values, specifically by averaging them.In particular, a weighted average can be calculated, for which each of the two individual values ​​is multiplied by a weighting factor.

[0044] The control system can be configured to acquire the parameter values ​​for calibration purposes when no weight is acting on the vehicle seat. This can be done in the manner described above, i.e., by activating the drive device to adjust the distance between the seat assembly and the base assembly in the first direction and acquiring the value of the drive device parameter during the adjustment in the first direction; and by activating the drive device to adjust the distance between the seat assembly and the base assembly in the second direction and acquiring the value of the drive device parameter during the adjustment in the second direction. Since the weight acting on the seat assembly is known (0 kg), the acquired values ​​can be used to determine the weight acting on the seat assembly.

[0045] Page 9

[0046] Values ​​are stored as a reference and / or used for calibration, e.g., of the model. Calibration corrects age-related effects, such as changes in efficiency, friction, etc., over the vehicle seat's lifespan. Optionally, the control system can be configured to automatically repeat the calibration at predefined intervals. This ensures consistently high accuracy in weight determination.

[0047] The drive device can include a brushless DC motor. Such motors allow for particularly precise adjustment of the adjustment speed by adjusting the rotational speed. Generally, the adjustment speed can be determined by the rotational speed.

[0048] The control system is optionally configured to receive seat occupancy data from a camera or other detection device (such as radar). This data can include camera images or other information that the control system analyzes, for example, to determine the height of a passenger and / or their position in the seat. This data can be used in conjunction with the calculated weight. Furthermore, the calculated weight can be corrected based on the seat occupancy data; for example, the passenger's position in the seat can be used to correct an underestimated weight.

[0049] The control system can include a memory in which a model is stored that establishes at least one relationship between the weight acting on the seat assembly and the input values ​​of adjuster position and the value of the measured parameter. This enables fast and reliable evaluation.

[0050] It can be advantageous if the control system is configured so that the acquisition of at least one parameter value in the first direction and / or in the second direction occurs within one complete revolution of a gear stage of the height adjustment device and / or the drive unit. This allows for the compensation of irregularities due to gear modulation, resulting in a more accurate measurement.

[0051] According to an advantageous further development, the control system can be configured to determine a vehicle inclination when detecting a weight acting on the seat assembly.

[0052] Please refer to page 10. Since the vehicle's tilt, in which the seat is installed, can influence the weight calculation, excessive tilt can lead to inaccurate weight readings. To prevent this, the vehicle's tilt can be used as an additional input value.

[0053] According to an advantageous further development, the control system can be configured to take temperature into account when determining the weight acting on the seat assembly. Temperature can influence certain material properties, particularly of a component of the height adjustment device and / or the drive unit, so that large temperature fluctuations can also affect the weight determination. To avoid this, temperature can be considered as an additional input value. For example, this could be the temperature in a vehicle interior.

[0054] The features described above can also be used to further develop the method and / or system described and / or claimed herein.

[0055] According to one aspect, a system is provided comprising the vehicle seat according to any configuration described herein and the camera and / or other detection device. According to a further development of the system, it may include a measuring device for measuring a setting of another seat adjustment device, in particular for setting a backrest angle and / or seat tilt.

[0056] According to one aspect, a computer-implemented method for determining a weight acting on a vehicle seat, in particular on a vehicle seat according to any embodiment described herein, is provided. The vehicle seat comprises a seat assembly, a backrest assembly, a base assembly supporting at least the seat assembly, and an adjustment device (e.g., a height adjustment device) for adjusting (e.g., a distance) the seat assembly and / or the backrest assembly relative to the base assembly by means of a drive device.The procedure comprises the following steps: reading a setpoint specifying an adjustment speed and / or rotational speed; and performing a weight measurement using the read setpoint by the following steps: activating the drive device to effect an adjustment of the seat assembly and / or the backrest assembly relative to the floor assembly according to the setpoint; acquiring at least one value of a parameter of the adjustment device and / or the drive device during the adjustment; and determining a weight acting on the vehicle seat based on the weight during the adjustment.

[0057] Page 11 recorded at least one value of the parameter, with several such weight measurements being carried out based on different target values. Regarding the advantages, please refer to the above information on the vehicle seat.

[0058] The procedure can include steps from the various configurations of the control system described above.

[0059] According to one aspect, a computer program product is specified, comprising instructions which, when executed by one or more computers (e.g., in the form of the control system described above), cause them to execute the procedure described above.

[0060] According to one aspect, a non-volatile, computer-readable storage medium is specified on which instructions are stored which, when executed by one or more computers (e.g., in the form of the control system described above), cause them to execute the procedure described above.

[0061] The underlying concept of the invention will be explained in more detail below with reference to the exemplary embodiments shown in the figures. The figures show:

[0062] Fig. 1 shows a schematic view of a vehicle seat with a

[0063] Height adjustment device which is supported by a base assembly, wherein the base assembly is exemplified as a longitudinal adjustment device;

[0064] Fig. 2 shows a view of a seat assembly of a vehicle seat;

[0065] Fig. 3 shows a top view of the arrangement according to Fig. 2;

[0066] Fig. 4 shows a partially enlarged view of the arrangement according to Fig. 2, depicting a drive device on a swivel element for connecting the seat assembly to a floor assembly in the form of a longitudinal adjustment device;

[0067] Fig. 5 shows an alternatively designed drive device for the vehicle seat according to Fig. 1; 2024 179 P

[0068] Page 12

[0069] Fig. 6 shows a method for determining a weight acting on the vehicle seat according to Fig. 1;

[0070] Fig. 7 shows the current of a drive motor against the position of a component adjusted by it;

[0071] Fig. 8 shows a phase current plotted against a rotational speed of a

[0072] Drive motor at three different load settings during a lifting adjustment; and

[0073] Fig. 9 shows the phase current of the drive motor plotted against the rotational speed at three different loads during a downward adjustment.

[0074] Fig. 1 shows a vehicle seat 1, which can be arranged, for example, as a front seat or as a rear seat in the second or third row of a vehicle. The vehicle seat 1 has a seat assembly 10, to which a backrest assembly 11 is attached in a tilt-adjustable manner and which is connected via a height adjustment device 12 to a base assembly 13 in the form of a longitudinal adjustment device for longitudinally adjusting the vehicle seat 1 along a longitudinal direction X.

[0075] The longitudinal adjustment device 13 typically has, as can be seen in Fig. 1 in conjunction with Figs. 2 and 3, two pairs of guide rails 130A, 131A, 130B, 131B, each arranged on one side of the seat assembly 10 and spaced apart from each other along a transverse direction Y perpendicular to the longitudinal direction X. The lower guide rails 131A, 131B are fixedly connected to a vehicle floor 2 and can be fixedly connected to it in a pre-assembly state. The upper guide rails 130A, 130B, on the other hand, are coupled to pivot elements 120A, 121A, 120B, 121B of the height adjustment device 12, via which the floor assembly 13 is connected to the seat assembly 10.

[0076] The pivot elements 120A, 121A, 120B, 121B, together with the upper guide rails 130A, 130B and side frame parts 100A, 100B of the seat assembly 10, form two pairs of four-bar linkages. The pivot elements 120A, 121A, 120B, 121B are each pivotable at one end on the respective upper guide rail 130A, 130B and at the other end pivotable with the seat assembly 10, e.g., with a cross tube 102 extending pivotably between the frame parts 100A, 100B of the seat assembly 10 (or with another part of the 2024 179 P).

[0077] Page 13

[0078] The seat assembly 10 is connected such that the height of the seat assembly 10 can be changed along a vertical direction Z (perpendicular to the longitudinal direction X and transverse direction Y) by pivoting the pivot elements 120A, 121A, 120B, 121B. This changes the distance between the seat assembly 10 and the floor assembly 13. The height adjustment device 12 is thus configured to adjust the distance between the seat assembly 10 and the floor assembly 13. To effect this adjustment, the height adjustment device 12 includes (at least) a drive unit 3 (with one or more drive motors).

[0079] The floor assembly, in this case the longitudinal adjustment device 13, supports the seat assembly 10. The seat assembly 10 supports the backrest assembly 11.

[0080] The height adjustment device 12 is an adjustment device for adjusting the seat assembly 10 (and, because the backrest assembly 11 is mounted on the seat assembly 10 in the example shown, also the backrest assembly 11) relative to the floor assembly, i.e. here to the longitudinal adjustment device 13, with the drive device 3.

[0081] The vehicle seat 1 further comprises a control system 14 coupled to the drive device 3, which is configured to perform the following steps:

[0082] Reading in a setpoint value that specifies an adjustment speed and / or a rotational speed; and

[0083] Performing a weight measurement with the input setpoint. Performing the weight measurement with the input setpoint comprises the following steps: o Activating the drive device 3 to effect an adjustment of the seat assembly 10 and / or the backrest assembly 11 relative to the floor assembly (here the longitudinal adjustment device 13) according to the setpoint, for example at the speed specified by the setpoint; o Recording at least one value of a parameter of the adjustment device (here the height adjustment device 12) and / or the drive device 3 during the adjustment (e.g. a current of the drive device); and 2024 179 P

[0084] Page 14 o Determining a weight acting on the vehicle seat 1, in particular a vehicle occupant sitting on the vehicle seat 1, based on at least one value of the parameter recorded during the adjustment.

[0085] The control system 14 is designed to perform weight measurements at different target values.

[0086] Furthermore, the control system 14 (but only as an example) is also configured to perform the following steps during each weight measurement: activating the drive device 3 to adjust the distance between the seat assembly 10 and the floor assembly in a first direction R1 according to the setpoint; acquiring at least one value of the parameter of the drive device 3 during the adjustment in the first direction R1; activating the drive device 3 to adjust the distance between the seat assembly 10 and the floor assembly in a second direction R2 opposite to the first direction R1, e.g., according to the setpoint; acquiring the value of the parameter of the drive device 3 during the adjustment in the second direction R2; and determining the weight acting on the seat assembly 10 based on the acquired values ​​of the parameter.The control system 14 is designed to perform this weight measurement at different target values.

[0087] As shown in Fig. 1, an adjustment in the first direction R1 increases the distance between the seat assembly 10 and the base assembly 13, while an adjustment in the second direction R2 decreases the distance between the seat assembly 10 and the base assembly 13. Only a minimal adjustment range is required for weight determination, e.g., a few mm in relation to the distance between the seat assembly 10 and the base assembly 13, so that the measurement is not noticeable or barely noticeable to a seat user.

[0088] Optionally, the measurement can be performed multiple times, e.g., three times in succession, and an average weight value is calculated. This can further increase the accuracy.

[0089] The drive device 3 can be activated at different adjustment speeds and has a minimum and a maximum adjustment speed. The control system 14 is configured to activate the drive device 3 at the minimum adjustment speed, e.g., first in the first direction R1 and then in the second direction R2, or alternatively at an adjustment speed lower than the maximum adjustment speed. This makes the weight measurement barely or not at all perceptible to a seated user. 2024 179 P

[0090] Page 15

[0091] The parameter in question is an electrical parameter, namely the current of at least one drive motor 31 of the drive device 3, e.g., the total current drawn by it or the current of one phase of the drive motor 31. Alternatively or additionally, the applied power can also be used as a parameter. The current corresponds to a respective torque (of the drive motor(s)) of the drive device 3. Depending on the magnitude of the applied weight, for example, from a passenger, a greater or lesser torque must be applied by the drive device 3 for an adjustment, e.g., by a predetermined adjustment range. Therefore, a predetermined relationship between the current (generally the parameter) and the applied weight (possibly the torque) can be established.The control system 14 uses the current adjustment position of the height adjustment device 12) to determine the weight. By performing the measurement in both adjustment directions R1 and R2, inaccuracies that have different effects in the different directions can be factored out, for example, by calculating an (optionally weighted) average of weight values ​​determined separately for the two directions R1 and R2. Inaccuracies due to friction, tolerances, wear, and the like can be factored out by taking measurements with the vehicle seat 1 unoccupied. For example, the difference between a current (generally: parameter values) during a downward measurement with the seat unoccupied and a downward measurement with the seat occupied is calculated and then multiplied by a first factor to determine the weight in the downward measurement.Furthermore, the difference between a current reading (generally: the parameter value) during an upward weight measurement with weight applied and a reading without weight applied is calculated and then multiplied by a second factor to determine the weight measured during the upward adjustment. The first and second factors can be different or the same. The weight is then determined, for example, by the sum of the two weight values.

[0092] The current (generally: the parameter value) for a given direction can be determined as the average value over a range of motion. Optionally, the start-up phase of the drive motor is excluded.

[0093] The parameter can also specify, for example, the maximum speed reached during adjustment, the adjustment range traveled within a certain time, or the adjustment time required for a specific adjustment range. 2024 179 P

[0094] Page 16

[0095] The predefined relationship is stored, for example, in a storage medium 140 of the control system 14. This relationship can be a model that assigns a value of an acting weight to each possible current value. Because these relationships depend on the adjustment direction in the example shown, the model also assigns a value of an acting weight to each possible current value with respect to an adjustment in the first direction R1 and with respect to an adjustment in the second direction R2, independently of each other. And because these relationships also depend on the adjustment position in the example shown, the model assigns a value of an acting weight to each possible current value for all possible adjustment positions of the height adjustment device 12. The model can comprise a LUT and / or a trained machine learning model.

[0096] To create the LUT and / or the training data for the machine learning model, test masses (e.g., 0 kg, 10 kg, 20 kg, 40 kg, and 80 kg, optionally with finer subdivisions) with various known weights can be placed on the seat assembly 10, and the parameter values ​​(especially at multiple adjustment positions) can be determined as described above. This allows for the creation of a table of factors that assigns a weight value to each parameter value (e.g., current) at each adjustment position. This table can be stored on the memory medium. Interpolation can be performed between any two entries in the table.

[0097] To compensate for changes in efficiency and due to friction, etc., the control system 14 is designed to perform calibration runs (e.g., regularly). For this purpose, the control system 14 is configured to record the parameter values ​​for calibration when no weight is acting on the vehicle seat 1.

[0098] A camera 4 (or another detection device such as radar) is aimed at the vehicle seat 1 to capture the size and position, or similar characteristics, of a passenger seated in the vehicle seat 1 in camera images. The camera 4 is directly or indirectly connected to the control system 14, so that the control system 14 receives data on the occupancy of the vehicle seat 1 from the camera 4. This data can be in the form of the captured images or in the form of previously evaluated information on weight, position, or similar characteristics. By combining the determined weight with information on size and position, the seat occupancy can be determined with particular precision. Furthermore, a weight measurement that is inaccurate, for example, due to an offset seating position, can be corrected in this way. For this purpose, a correction table can be stored in the storage medium, which accounts for various seating positions.

[0099] Page 17

[0100] (e.g., further forward, further back) assigns correction factors. Since occupant cameras are increasingly installed in modern vehicles, such a measure is particularly easy to implement. The control system 14 is designed to receive the seat occupancy data based on the camera images, e.g., via a dedicated interface.

[0101] The exemplary design of the height adjustment device 12 is explained in more detail below.

[0102] The frame parts 100A, 100B of the seat assembly 10 are connected to each other at a rear end via the cross tube 102. The cross tube 102 is (in this example) pivotally mounted on the frame parts 100A, 100B and carries the associated rear pivot elements 121A, 121B.

[0103] In a front area, a seat pan 101 is arranged on the frame parts 100A, 100B to form a seat surface of the seat assembly 10.

[0104] In the illustrated embodiment, the drive device 3 of the height adjustment device 12 is arranged, for example, on the rear pivot element 121A on the side of the guide rail pair 130A, 131A, as can be seen in Figures 2 and 3 in conjunction with Figure 4. The drive device 3 is designed as a spindle drive and serves to introduce an adjusting force into the pivot element 121A, so that by pivoting the pivot element 121A, the pivot elements 120A, 121A, 120B, 121B can be pivoted as a whole, thereby adjusting the height of the seat assembly 10, i.e., changing the distance between the seat assembly 10 and the base assembly 13.

[0105] At a set seat height, the seat assembly 10 is held in position on the swivel element 121A by the drive device 3. The drive device 3 is designed to be sufficiently robust to absorb and dissipate forces acting on the seat assembly 10.

[0106] Referring now to Figures 2 to 4, the drive device 3 has a spindle 30 which is pivotably connected at one end to the associated guide rail 130A via a bearing element. 2024 179 P

[0107] Page 18

[0108] The swivel element 121A is coupled to an attachment connected to the guide rail 130A and is pivotably mounted on the guide rail 130A (here via a bearing bolt).

[0109] The spindle 30 extends substantially perpendicularly from the end connected to the guide rail 130A, with a threaded shaft 300 on which an external thread is formed. An adjusting gear 32 is operatively connected to the spindle 30 such that, by driving the adjusting gear 32, it can be adjusted longitudinally along a longitudinal extension direction L relative to the spindle 30. This allows the length of an end of the spindle 30, which is pivotably mounted on the guide rail 130A, to be changed. This, in turn, introduces an adjusting force into the pivoting element 121A, thus adjusting the distance between the seat assembly 10 and the base assembly 13.

[0110] The adjusting gear 32 has a spindle nut and a drive element in the form of a drive worm, which engages with an external toothing of the spindle nut via a worm gear. The drive element is driven by a drive motor 31, so that the spindle nut can be set into a rotary motion by the drive motor 31. The spindle nut engages with the external thread of the spindle 30 via an internal thread such that, by rotating the spindle nut, it rolls along the spindle 30 and is thereby adjusted longitudinally along the longitudinal direction L relative to the spindle 30.

[0111] Optionally, the height adjustment device 12 includes a further drive motor 31, which can be arranged, for example, in a mirror image to the drive motor 31 on the rear pivoting element 121B on the side of the guide rail pair 130B, 131B. This is illustrated schematically in Fig. 3. Based on the current values ​​of both drive motors, the acting weight can be determined with particular accuracy.

[0112] The drive motors 31 are brushless direct current motors (BLDC motors) whose speed and torque can be adjusted with particular precision.

[0113] The adjustment gear 32 is pivotably mounted on the pivoting element 121A. During an adjustment movement in which the length of the section of the spindle 30 extending between the adjustment gear 32 and the rail-side end is changed, the adjustment gear 32 can thus pivot on the pivoting element 121A in order to achieve 2024 179 P

[0114] Page 19 to compensate for a change in position of the swivel element 121A relative to the base assembly 13.

[0115] The drive motor 31 is pivotably mounted on the swivel element 121A via the adjustment gear 32. When the swivel element 121A is moved, the drive motor 31 and the adjustment gear 32 move together with the swivel element 121A.

[0116] Fig. 5 shows an example of an alternatively designed drive device for the vehicle seat according to Fig. 1, which has a drive motor 31 mounted on the seat assembly 10, which drives a pinion 33 via a gearbox. The pinion 33 meshes with a curved toothed segment 34, which is attached to the upper guide rail 130A. Otherwise, the operating principle is as described above.

[0117] Fig. 6 shows a method for determining a weight acting on the vehicle seat 1, the method comprising the following steps:

[0118] Step S10: Reading in a setpoint value that specifies an adjustment speed and / or a rotational speed.

[0119] Step S11: Perform a weight measurement with the read-in target value by performing the following steps.

[0120] Step S110: Activate, by means of the control system 14, the drive device 3 to effect an adjustment of the seat assembly 10 and the backrest assembly 11 relative to the floor assembly 13 according to the read setpoint.

[0121] Step S111: Detect, by means of the control system 14, at least one value of the parameter (e.g. the current or the torque) of the drive device 3 (and / or the height adjustment device 12) during adjustment.

[0122] Step S112: Determine, using the control system 14, a weight acting on the vehicle seat 1, in particular on the seat assembly 10, based on the detected at least one value of the parameter.

[0123] Several weight measurements are performed with different target values ​​(in an alternative configuration with the same target value). The procedure returns from 2024 179 P

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[0125] Step S112 therefore returns to step S10, reads a different target value and performs the weight measurement again according to step S11 with this different target value.

[0126] Regarding specific implementations of the procedure, reference is made to the above and following information on control system 14 to avoid repetition. The procedure may include corresponding procedural steps that correspond to the functionality of control system 14 described herein.

[0127] The storage medium 140 contains a computer program product comprising instructions which, when executed by one or more computers, in particular when executed by the control system 14 (e.g. by its processor 142), cause it to carry out the procedure described above.

[0128] The single setpoint input can be the first setpoint. The control system might, for example, input a second setpoint along with the first. Alternatively, the control system 14 can first input the first setpoint and then input the second setpoint at a later time.

[0129] The setpoint values ​​can be stored in the storage medium 140 and read by the control system 14 (e.g., the processor 142). In this example, the control system 14 also has an (optional) interface 141, which is configured to receive the setpoint values ​​via interface 141.

[0130] One possibility is that the control system 14, as part of a measurement process, first performs a weight measurement with the first target value as described (with the steps of activation, acquisition, and determination) and then performs another weight measurement with the second target value (different from the first target value) (with the steps of activation, acquisition, and determination). For example, the target values ​​are speed target values ​​(e.g., 1000 RPM and 2000 RPM) to which the control system sets the drive device 3. The two weight measurements are performed, for example, immediately one after the other, or with a time offset but without any other adjustment movements of the drive device 3 in between, and / or with a time offset that is less than a predefined maximum value. The two weight measurement results can be compared to perform a plausibility check.If the two results are within a predetermined proximity to each other (e.g., if one result is within a predetermined tolerance range around the other result, or if the results are not 2024 179 P.

[0131] If the two measurements (page 21) are further apart than a predefined maximum difference, the measurement process is considered valid and one or the other measurement is displayed as the overall result. Otherwise, an error message is displayed. The two results can also be combined and displayed as a combined result. For example, the average of the two results can be calculated.

[0132] Alternatively, a measurement can also be carried out using only a setpoint; however, the control system 14 can adapt the measurement to the respective conditions of the measurement via a correspondingly selected or set setpoint, in particular to the weight to be measured, the temperature and a requested measurement accuracy.

[0133] Since, in the present example, measuring a large weight at a lower rotational speed is more accurate than at a higher rotational speed (and conversely, measuring a small weight at a higher rotational speed is more accurate), the control system 14 is designed to read the target value (or, if a measurement is taken at multiple rotational speeds, the multiple target values) based on a previously determined weight acting on the vehicle seat 1. Thus, an initial (rough) measurement of the weight is taken, and the result is then used in the actual measurement. If the weight is measured periodically (e.g., every 10 minutes or the like), the previous measurement can simply be used. Alternatively, for example, if such a measurement is not (yet) available, another measuring device can be used, such as the camera 4 or the like, as already described.An initial weight estimate allows for the use of an optimal target value for that weight. Furthermore, it is possible to first perform an initial weight measurement using a target value for an average weight (and / or an average target value). The result of this measurement is then used to read in a target value intended for that weight and to perform a further weight measurement using this target value. For example, the storage medium 140 stores a corresponding target value for each possible weight value, or a functional relationship that outputs a corresponding target value for an input weight.

[0134] For example, if a larger previously determined weight acts on vehicle seat 1, a smaller target value will be read than if a smaller previously determined weight acts on vehicle seat 1.

[0135] Furthermore, a temperature, e.g. of the environment, can be used by a component of the height adjustment device 12 or the drive device 3 as a preselection parameter for the setpoint 2024 179 P

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[0137] (e.g., the rotational speed or the adjustment speed). At low temperatures, the adjustment current increases sharply. At low temperatures (e.g., below a predefined threshold), the rotational speed can be reduced, resulting in a lower phase voltage. A temperature measurement, e.g., provided to the control system 14 by a temperature sensor 35 to measure the temperature of the drive device 3 (see Fig. 1), is then used, e.g., to read in a corresponding setpoint (e.g., via a tabular or functional relationship between them).

[0138] Furthermore, a measurement accuracy requirement can be defined to read in the target value based on the requested accuracy. For example, a lower target value can be read in for high measurement accuracy (among several accuracy levels, e.g., high and low, or high, medium, and low, etc.) than for low measurement accuracy. A high rotational speed enables fast measurement but may result in fewer measurement points and a greater incidence of disturbances. A low rotational speed results in a comparatively slower measurement but allows for improved averaging and / or filtering.

[0139] Furthermore, it can be provided that the drive device 3 is activated in such a way that, for a larger setpoint, an adjustment is made over a greater travel distance than for a smaller setpoint. This allows consistent measurement accuracy to be achieved even if a slow speed is selected for other reasons, while conversely, the measurement duration can be kept short.

[0140] Optionally, the control system 14 is configured to use several or even all of the aforementioned options for selecting the setpoint(s). For example, the setpoint can be read based on a preliminary weight, a current temperature, and / or a desired measurement accuracy.

[0141] Optionally, the starting current (i.e., at different speeds during a speed ramp) can be excluded from the measurement. Alternatively, this starting current can be included in the measurement.

[0142] The control system 14 is configured to vary the rotational speed and / or adjustment speed during weight measurement according to the target values. This can be done in two separate measurement processes. It may be provided that the rotational speed and / or adjustment speed can be varied during an ongoing weight measurement according to 2024 179 P

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[0144] The setpoint values ​​are varied. For example, the rotational speed and / or adjustment rate is changed during movement. The drive device 3 can switch directly from the first setpoint to the second setpoint without stopping.

[0145] Fig. 7 illustrates an exemplary current profile of the drive device 3. Specifically, Fig. 7 shows the current of one phase of the drive motor 31 of the drive unit 3 against the adjustment path. The position is represented on the x-axis as the number of motor revolutions. One complete revolution of the motor shaft corresponds to one motor revolution.

[0146] As can be seen in the diagram in Fig. 7, the current fluctuates between a maximum and a minimum within a single motor revolution, resulting in a wavy current profile over several revolutions. If the average current is calculated for each motor revolution (or another corresponding window), these fluctuations can be factored out. These average values ​​are illustrated by a dashed line. However, it is also evident that the average values ​​exhibit a variable pattern. A repeating pattern is discernible, extending over a fixed number of motor revolutions and then repeating. This pattern is illustrated by vertical lines. This pattern results, for example, from the design of the drive device 3 and / or the adjustment unit, in particular from the design of the adjustment gear 32.

[0147] As can be seen in Fig. 7, the individual sections, each containing a complete pattern, also differ from one another. For example, the pattern in the center of the diagram has a higher overall average current than the pattern to its left and a lower average than the pattern to its right. Furthermore, the maximum deviation of the current within a pattern—that is, the difference between the lowest and highest current values ​​within a pattern—can vary between the individual sections. This difference is illustrated for the central pattern in Fig. 7 by a double vertical arrow.

[0148] The acting weight can be determined from the measured values ​​shown, e.g., by calculating the weight from the average current of a sample using a predetermined conversion rule (e.g., a LUT). For example, the conversion rule assigns a weight value to a current value in each position of the height adjustment device 12. 2024 179 P

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[0150] The control system 14 comprises the computer-readable storage medium 140 in which a model is stored with which at least one relationship is established between the weight acting on the vehicle seat 1, in particular on the seat assembly 10, and the adjuster position and / or the value of the measured parameter (e.g. the current of the drive motor, e.g. of one of several phases or the currents of all phases).

[0151] Furthermore, it may be provided that the determination of the weight acting on vehicle seat 1 is carried out based on the difference between the parameter value recorded during adjustment with a first target value and the parameter value recorded during adjustment with a second target value different from the first. This eliminates the need for calibration.

[0152] Fig. 8 shows phase currents of one phase of the drive motor 31 during a lifting movement with different loads: 0 kg (i.e., an empty measurement), 40 kg and 80 kg at different rotational speeds (RPM, revolutions per minute) of the drive motor 31. Fig. 9 shows this analogously for a lowering adjustment movement.

[0153] This shows that the current varies at different rotational speeds. Furthermore, it shows that the current difference at different speeds is dependent on the load. Therefore, a simplified calibration procedure can be performed without a blank measurement. For example, a measurement is taken at 2000 RPM and another at 4000 RPM, and the applied weight is determined solely from the difference between the results of these two measurements.

[0154] A comparison of Figures 8 and 9 shows that, in the downward direction, compared to the upward direction, some of the curves reverse their vertical order due to mechanical factors. This is because, during lifting, the greater the weight applied, the more current is required. During lowering, less current is initially required with increasing weight, but with even greater weight, friction necessitates a higher current again. 2024 179 P

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[0156] Reference symbol list

[0157] 1 vehicle seat

[0158] 10 Seat component assembly

[0159] 100A, 100B frame part

[0160] 101 Seat tub

[0161] 102 Cross tube

[0162] 11 Backrest assembly

[0163] 12 Height adjustment device

[0164] 120A, 120B Swivel element

[0165] 121A, 121B Swivel element

[0166] 13 Floor assembly (longitudinal adjustment device)

[0167] 130A, 130B guide rail

[0168] 131A, 131B Guide rail

[0169] 14 Control system

[0170] 140 storage media

[0171] 141 Interface

[0172] 142 processor

[0173] 2 Vehicle floor

[0174] 3 Drive device

[0175] 30 spindle

[0176] 300 threaded shaft

[0177] 31 Drive motor

[0178] 32 adjustable gearboxes

[0179] 33 sprockets

[0180] 34 tooth segment

[0181] 35 Temperature sensor

[0182] 4 cameras

[0183] L Longitudinal direction

[0184] R1, R2 direction

[0185] X Longitudinal direction

[0186] Y transverse direction

[0187] Z Altitude direction

Claims

2024 179 P Page 26 Claims 1. Vehicle seat (1) comprising a seat assembly (10), a backrest assembly (11), a base assembly (13) supporting at least the seat assembly (10) and an adjustment device (12) for adjusting the seat assembly (10) and / or the backrest assembly (11) relative to the base assembly (13) with a drive device (3), characterized by a control system (14) coupled to the drive device (3), which is configured to perform the following steps: Reading in a setpoint value that specifies an adjustment speed and / or a rotational speed; and Performing a weight measurement with the input setpoint by: o Activating the drive device (3) to effect an adjustment of the seat assembly (10) and / or the backrest assembly (11) relative to the floor assembly (13) according to the setpoint; o Capturing at least one value of a parameter of the adjustment device (12) and / or the drive device (3) during the adjustment; and o Determining a weight acting on the vehicle seat (1) based on the at least one value of the parameter captured during the adjustment, wherein the control system (14) is configured to perform the weight measurement with different setpoints.

2. Vehicle seat (1) according to claim 1 , characterized in that the read-in setpoint is a first setpoint and the control system (14) is configured to read in a second setpoint together with the first setpoint or to read in the first setpoint first and the second setpoint at a later time.

3. Vehicle seat (1) according to claim 2, characterized in that the control system (14) is configured to perform the steps of activating, detecting and / or determining with the first setpoint and then to perform the steps of activating, detecting and / or determining with the second setpoint. 2024 179 P Page 27 4. Vehicle seat (1) according to claim 3, characterized in that the control system (14) is configured to compare and / or calculate the weight determined with the first target value and the weight determined with the second target value.

5. Vehicle seat (1) according to claim 3 or 4, characterized in that the control system (14) is configured to determine the weight acting on the vehicle seat (1) based on a difference between the value of the parameter recorded during adjustment with the first setpoint and the value of the parameter recorded during adjustment with the second setpoint.

6. Vehicle seat (1) according to one of the preceding claims, characterized in that the control system (14) comprises a storage medium (140) in which the setpoint values ​​are stored, and / or comprises an interface (141), wherein the control system (14) is configured to read the setpoint values ​​from the storage medium (140) and / or to receive the setpoint values ​​via the interface (141).

7. Vehicle seat (1) according to one of the preceding claims, characterized in that the control system (14) is configured to read the setpoint based on a previously determined weight acting on the vehicle seat (1).

8. Vehicle seat (1) according to claim 7, characterized in that the control system (14) is configured to read a smaller setpoint value when a larger previously determined weight acts on the vehicle seat (1) than when a smaller previously determined weight acts on the vehicle seat (1).

9. Vehicle seat (1) according to one of the preceding claims, characterized in that the control system (14) is configured to read the setpoint based on a temperature.

10. Vehicle seat (1) according to one of the preceding claims, characterized in that the control system (14) is configured to detect a requirement for measurement accuracy and to read in the target value based on the requested measurement accuracy. 2024 179 P Page 28 11. Vehicle seat (1) according to one of the preceding claims, characterized in that the control system (14) is configured to activate the drive device (3) in such a way that, at a larger setpoint, an adjustment is made over a larger adjustment range than at a smaller setpoint.

12. Vehicle seat (1) according to one of the preceding claims, characterized in that the parameter is an electrical parameter, in particular a current, a voltage or a power and / or that the parameter specifies a torque and / or that the parameter specifies a maximum speed achieved during adjustment.

13. Vehicle seat (1) according to one of the preceding claims, characterized in that the adjusting device (12) is a height adjusting device for adjusting a distance between the seat part assembly (10) and the floor assembly (13), wherein the control system (14) is configured to activate the drive device (3) for adjusting the distance between the seat part assembly (10) and the floor assembly (13) in one direction (R1).

14. Vehicle seat (1) according to one of the preceding claims, characterized in that the control system (14) has a storage medium (140) in which a model is stored which assigns to each possible value of the parameter a value of an acting weight, wherein the model assigns to each possible value of the parameter to several possible setting positions of the adjustment device (12) a value of an acting weight.

15. Vehicle seat (1) according to one of the preceding claims, characterized in that the control system (14) is configured to record the values ​​of the parameter for calibration purposes when no weight acts on the vehicle seat (1).

16. Method for determining a weight acting on a vehicle seat (1), the vehicle seat (1) comprising a seat assembly (10), a backrest assembly (11), a base assembly (13) supporting at least the seat assembly (10), and an adjustment device (12) for adjusting the seat assembly (10) and / or the backrest assembly (11) relative to the base assembly (13) with a drive device (3), in particular according to one of the preceding claims, the method comprising the following steps: 2024 179 P Page 29 - Reading (S10) a setpoint value that specifies an adjustment speed and / or a rotational speed; and - Performing (S11) a weight measurement with the input setpoint by: o Activating (S110) the drive device (3) to effect an adjustment of the seat assembly (10) and / or the backrest assembly (11) relative to the floor assembly (13) according to the setpoint; o Capturing (S111) at least one value of a parameter of the adjustment device (12) and / or the drive device (3) during the adjustment; and o Determining (S112) a weight acting on the vehicle seat (1) based on the at least one value of the parameter captured during the adjustment, whereby weight measurements are performed with different setpoints.

17. Computer program product comprising instructions which, when executed by one or more computers, cause them to execute the method according to claim 16.

18. Non-volatile, computer-readable storage medium (140) on which instructions are stored which, when executed by one or more computers, cause them to execute the method according to claim 16.

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