Method and adjusting device for adjusting flap of motor vehicle

Abstract

The invention relates to a method and an adjusting device for adjusting a flap of a motor vehicle. The proposed solution relates to a method for adjusting a flap, in particular a tailgate or a front trunk lid, of a motor vehicle by means of an adjusting device, comprising the following steps: initiating an opening movement of the flap, determining at least one motor parameter of a drive motor of the adjusting device during the opening movement, in order to obtain at least one measured value of the at least one motor parameter, a deviation of the at least one measured value from a predetermined comparison value is determined, and whether a load condition is present is determined based on the deviation. The proposed solution also relates to an adjusting device.

Description

Technical Field

[0001] The proposed solution relates, according to a first aspect, to a method for adjusting a flap of a motor vehicle according to claim 1, and according to a second aspect to an adjustment device for a motor vehicle according to claim 14. Background Art

[0002] The flap can be, for example, a tailgate, a front luggage compartment lid or an engine hood. For adjusting such a flap, an adjustment device is usually provided, by means of which the adjustment can be carried out in a force - manipulable manner. The user of the motor vehicle only needs to trigger the adjustment device and the flap will then open automatically without the user having to apply the force for the adjustment himself. As the flap opens, it can at least sectionally release a loading space accessible to the user. The adjustment device is usually designed such that the flap opens along an adjustment stroke at a predetermined speed within a predetermined adjustment duration. Whether the predetermined adjustment duration can be adhered to mainly depends on the weight to be adjusted by the adjustment device, which consists of the weight of the flap and possibly additional weight. For example, if there is snow on the flap, the adjustment may proceed more slowly because, in addition to moving the weight of the flap, the snow must also be moved.

[0003] Generally, the holding force that can hold the flap in a certain position is less than the adjustment force that the adjustment device can exert for adjusting the flap. Therefore, when there is a certain additional weight, and the adjustment device can only move the flap along the initial section of the adjustment stroke before it overloads and aborts the opening movement, this will create a dangerous situation for the user. It may thus happen that after the flap has opened through the initial section of the adjustment stroke, it closes again in an unexpected manner for the user. If in this situation the user has already approached the loading space although the flap may not be fully open yet, the user will be pinched between the closed flap and the edge of the loading space and may be injured thereby. Summary of the Invention

[0004] The proposed solution consists in providing a method that enables safe use of the flap.

[0005] According to a first aspect of the proposed solution, a method for adjusting a flap of a motor vehicle by means of an adjustment device is described, wherein the flap is in particular a tailgate or a front luggage compartment lid. The method comprises the following steps: - Initiating an opening movement of the flap, - Determining at least one motor parameter of a drive motor of the adjustment device during the opening movement in order to obtain at least one measured value of the at least one motor parameter, - Determining the deviation of the at least one measured value from a predetermined comparison value, and - Determine whether there is a load condition based on a deviation.

[0006] The proposed solution is based on the consideration that a load condition poses a risk to the use of the flap. Thus, what the method can achieve is to determine whether there is a load condition already when starting the opening movement of the flap. This can make the use of the flap safer, because dangerous situations such as the user being pinched between the flap and the edge of the loading space that can be closed by the flap can be avoided from the very beginning. This is because determining whether there is a load condition enables the adjusting device to react appropriately (and, if necessary, depending on the size of the load).

[0007] In one design, the load condition includes the following situation: in this situation, the sum of the self-weight of the flap and the additional weight additionally loaded on the flap exceeds a predetermined maximum weight.

[0008] In principle, the load condition can refer to the following situation: in this situation, the flap is additionally loaded with an additional weight in addition to its own weight. Since the additional weight will threaten the proper opening movement of the flap. Thus, determining the load condition can include: optionally determining the presence and / or size of the additional weight. For example, the scale of the deviation of at least one measured value from a predetermined comparison value can, for example, lead to a conclusion about the size of the additional weight. However, directly determining the size of the additional weight (e.g., in kilograms) is not absolutely necessary, although this is certainly conceivable and feasible.

[0009] Determining whether there is a load condition based on the deviation of at least one measured value from a predetermined comparison value can achieve that the adjusting device can take measures, for example, starting from a specific additional weight, in order to avoid situations that are dangerous for the user. The additional weight can, for example, be between 10 kg and 20 kg, especially 13 kg. For example, in the case of a tailgate, the flap may have a spoiler and a flap body. In the case of an additional weight of 13 kg, the spoiler and the flap body may, for example, bear 6.5 kg each in the form of a snow load. In principle, the additional weight can exist in the form of a snow load, dirt (such as soil), or other objects placed on or attached to the flap. Thus, when adjusting the flap, the adjusting device must be able to move the weight of the flap itself and the additional weight. Even when this movement may be possible at least for the initial section of the adjustment stroke that the flap can follow, it may happen that the adjusting device cannot complete the adjustment out of the initial section.

[0010] By the proposed solution, the use of the tailgate can be made safe already when starting the opening movement, so that the undesired pinching situation for the user can be avoided from the very beginning, for example, by stopping the opening movement in advance within the initial section.

[0011] In a design, at least one motor parameter is adaptively adjusted in a first load case, while the opening movement is stopped in a second load case. These examples illustrate that the adjustment device can not only determine whether a load case exists based on the deviation of at least one measured value, but also react appropriately to it.

[0012] In the first load case, there may be a lower additional weight (e.g., below 13 kg). In the first load case, the self-weight of the flap and the additional weight do not exceed a predetermined maximum weight, for example. In such a load case, the flap can perform the desired opening movement, and the user of the flap is not exposed to a dangerous situation. By adaptively adjusting at least one motor parameter, the same performance of the opening movement with the additional weight and without the additional weight can be achieved (the user experience is the same as expected for an unloaded flap). For example, the desired performance may include adjusting the flap within a predetermined adjustment duration.

[0013] In the second load case, there may be an additional weight higher than in the first load case. The self-weight of the flap and the additional weight may exceed the predetermined maximum weight here, for example. In such a load case, the desired opening movement of the flap can still be achieved by adaptively adjusting at least one motor parameter (the adjustment device may then be applied with the maximum motor voltage for adjusting the flap). However, if the holding force for the flap is less than the adjustment force that can be exerted by the adjustment device, a dangerous situation will occur even after the desired opening movement of the flap, because the flap may close under the action of the additional weight. Therefore, even when the flap may still achieve the desired opening movement, it makes sense to stop the opening movement. Here, the holding force can be exerted by the adjustment device in the form of mechanical and / or electromagnetic friction forces (in the transmission and / or at least one drive motor).

[0014] If the flap can no longer achieve the desired opening movement, the opening movement can be stopped immediately (also to protect the adjustment device against overload), or at least within an initial section of the adjustment stroke, which can generally include 10 cm, for example. The adjustment stroke generally extends between the closed position and the open position of the flap, where the loading space is closed in the closed position and the loading space is released in the open position. After stopping, the flap can then be held in an intermediate position between the closed position and the open position. Alternatively, the flap can be adjusted back to the closed position after stopping. The advantage of the proposed solution is that if the additional weight is high, it is also conceivable and feasible to stop and hold the flap in the closed position.

[0015] Stopping the opening movement within a predefined initial section can have several advantages. First, the holding force to be applied can be smaller within the initial section than in the open position, thus still enabling safe holding. In addition, by remaining in the intermediate position, the user is warned of the dangerous situation. In addition, the possible pinch area between the flap and the loading space can thereby be kept small. Stopping the opening movement early can also be preferred in order to prevent loads (such as in the form of snow accumulation) from being thrown out, pushed or slipped into the loading space due to the adjustment of the flap (especially in the case of a front luggage compartment lid) or (especially in the case of a tailgate) being thrown out, pushed or slipped in the direction of the user.

[0016] In one design, at least one measured value is determined within the first third of the adjustment travel traversed by the flap during the opening movement. Alternatively or additionally, at least one measured value is determined within the first third of the adjustment duration elapsed during the opening movement. The special feature of the proposed solution is that it can cope with loads that are present before the start of the opening movement, i.e., from the very beginning, such as a snow load. In order to avoid dangerous situations that occur during or even after the opening movement is completed, the method (and the proposed adjustment device) can be used to identify the load in advance. For example, this can be ensured by determining at least one measured value within the first third of the adjustment travel and / or within the first third of the adjustment duration. In particular, at least one measured value can be determined within the first 10 cm of the adjustment travel (starting from the closed position of the flap), within an opening angle of 1° between the flap and the loading space, or within the first second of the adjustment duration, especially within the first 200 ms. The adjustment travel can in principle be given in the form of (arc) length or in the form of an angle. Therefore, the deviation of at least one measured value from a predefined comparison value can be carried out depending on the length and / or depending on the angle. For this purpose, one or more comparison values along the adjustment length, the opening angle, and / or along the adjustment duration can be provided.

[0017] In a design, at least one motor parameter includes the motor speed, motor voltage, or motor current. The motor speed can be the following parameter here: This parameter starts from a lower initial value (for example, 800 revolutions per minute) at the start of the opening movement and increases to a maximum value during the opening movement in order to complete the largest section of the opening movement at this maximum value, and then decreases again after most of the adjustment duration has elapsed in order to end the opening movement smoothly (rather than suddenly). In the case of a load, it may occur that the initial value of the motor speed cannot be reached using the parameters originally set for adjusting the flap without additional weight. The parameters can then be adaptively adjusted during the determination of the load case. These parameters can include the motor current, motor voltage, and / or the control parameters of the control unit (optionally with a PID controller). By adaptively adjusting the parameters, the utilization rate of the adjustment device can be increased to a predetermined limit or to one of the system limits inherent to the adjustment device. The inherent limit can be the maximum limit for which the adjustment device is designed.

[0018] The motor voltage can be the following parameter: This parameter increases at the start of the opening movement in order to accelerate the flap by increasing the motor speed and then decreases again to a higher level after the initial phase in order to be able to carry out the opening movement at a constant speed (without further acceleration). In the case of a load, a higher motor voltage may be required for acceleration. The motor voltage can be limited upwards to a maximum voltage, for example, limited by the (possibly temperature-dependent) battery voltage of the motor vehicle. In the corresponding load case, the maximum voltage can be reached at least during the initial phase, where, after the initial phase, the motor voltage can decrease again (first load case), or if the load acting on the flap is very high (second load case), it can always correspond to the maximum motor voltage. The motor voltage can be predetermined in the form of a fraction of the maximum motor voltage via a pulse width modulation signal (PWM signal).

[0019] The motor current can be the following parameter: This parameter is set to a particularly high value (peak value) at the start of the opening movement, if necessary for a longer period of time, or above a threshold value, and then decreases to a lower value during the opening movement (possibly already falling in the initial phase), and this lower value can remain constant during the opening movement. In the case of a load, the peak value may need to be maintained for a longer time in order to move the flap.

[0020] In a design, determining the deviation includes: determining the difference between at least one measured value and a predetermined comparison value. Alternatively or additionally, determining the deviation includes: determining the area difference between the measurement curve passing through at least two measured values and the comparison curve passing through the predetermined comparison values. Additionally alternatively or additionally, determining the deviation includes: determining the difference in the slopes of the measurement curve and the comparison curve.

[0021] Thus, determining the deviation of at least one measured value from a predetermined comparison value can in principle be carried out in different ways. For example, one or more predetermined comparison values can be stored in the storage device of the regulating device. These comparison values can represent here the desired course (e.g., in the case of motor speed) or the extreme course (e.g., in the case of motor voltage) of at least one motor parameter, or a threshold value of the course (e.g., in the case of motor current). Each comparison value can be assigned to a value within the regulation duration or within the regulation stroke for this purpose.

[0022] For example, if the difference between at least one measured value and a predetermined comparison value for one or more values within the regulation duration or within the regulation stroke exceeds a predetermined tolerance (e.g., the average deviation exceeds 20%), a load condition can be determined to exist.

[0023] Alternatively or additionally, determining the deviation can be based on a measurement curve through at least two measured values and a comparison curve through at least two predetermined comparison values. In principle, it is conceivable and feasible to respectively set a large number of measured values and a large number of comparison values as the basis for the measurement curve or the comparison curve. Determining the deviation can in particular be based on the size of the area enclosed between the comparison curve and the measurement curve. The size of the area can be determined by, respectively, integrating the area below the measurement curve and the area below the comparison curve and subtracting the results from each other in order to obtain the area between the curves as the difference. If the measurement curve and the comparison curve intersect, the area difference can also be zero. Determining the deviation based on the area between the curves (possibly additionally) can allow for a more comprehensive determination than that based on the difference between values.

[0024] Alternatively or additionally, determining the deviation can be based on the difference in the slopes of the measurement curve and the comparison curve. The slope can be obtained respectively from the differentiation of the function approximated to calculate the measurement curve or the comparison curve. In particular, the further course of the deviation can also be taken into account in the determination via the slope.

[0025] In the case of motor speed, one or more of the comparison values can include the desired course of the motor speed (e.g., ramping up to a predetermined value and then remaining within most of the regulation duration or regulation stroke). Determining the deviation can be directed at how much at least one measured value deviates from the desired course.

[0026] In the case of the motor current, one or more of the comparison values can in particular include, for example, a threshold value in the form of a constant current value. The purpose of determining the deviation of the motor current can be to determine for how long a period of time or over what adjustment travel the measured value of the motor current is above the threshold value or at a peak corresponding to the maximum current. The length of the period of time can be used to determine whether a load situation exists. This is because in the case of a load situation, the adjusting device has to exert a very large adjusting force to move the flap, which can be reflected in the motor current.

[0027] In one design, determining the deviation of the motor voltage includes determining the difference between at least one measured value of the motor voltage and a predetermined comparison value in the form of the maximum voltage of a motor vehicle battery. Here, efforts can be made to make this difference as large as possible in order to protect the battery of the motor vehicle. This is because in principle the flap can already be accelerated with a motor voltage below the battery voltage. A small difference between the maximum voltage and the at least one measured value can indicate a load situation, because the adjusting device has to use up the battery voltage in order to move the flap in the case of a high load during the opening movement.

[0028] In one design, determining whether a load situation exists is based on the deviations determined for at least two motor parameters. By combining the deviations of more than one motor parameter from the predetermined comparison values in this way, the accuracy of the determination can be improved. For example, if the area between the measured curve of the motor speed and the corresponding comparison curve is large (for example, greater than 10% of the area below the comparison curve within an adjustment travel of 5 cm), and at the same time the deviation between the measured value of the motor voltage and a predetermined comparison value in the form of the maximum voltage is small (for example, less than 10% of the maximum voltage within an adjustment duration of 500 ms), then it can be determined that a load situation exists.

[0029] It is also conceivable and feasible to calculate, based on at least one measured value (or their measured curves) of the motor current, the motor speed and the motor voltage, the adjusting force exerted by the adjusting device after the start of the opening movement, and to compare this adjusting force with at least one predetermined comparison value (or comparison curve) for the adjusting force in order to determine whether a load situation exists based on the adjusting force. For example, at least one predetermined comparison value can correspond to the adjusting force that has to be exerted to adjust the flap in the case of no load. If the adjusting force is greater than at least one predetermined comparison value, then a load situation may exist. In addition, the load situation can also be quantified by determining the difference between the adjusting force and at least one predetermined comparison value. The measures (such as continuing the opening movement or stopping the opening movement) can be carried out depending on the magnitude of the difference. This force calculation can be carried out as an addition or alternative to the determination based on the deviation of at least one measured value from the predetermined comparison value.

[0030] In one design, the method further includes: determining at least one additional measurement value of at least one motor parameter, determining the deviation of at least one additional measurement value from a predetermined comparison value, comparing the deviation of at least one measurement value and at least one additional measurement value from their respective comparison values and determining based on this comparison whether there is a varying load condition (Umlastungsfall).

[0031] The varying load condition may include a redistribution of the load that the adjusting device has to adjust. Such a redistribution may cause a change in the center of gravity of the mass to be adjusted, which affects the opening movement and may thus be undesirable or even dangerous for the user. At least one motor parameter may change suddenly due to the redistribution (or be changed by the regulation unit further described below in order to ensure the desired opening movement in view of the redistribution). For example, the redistribution may be caused by snow sliding on the flap.

[0032] The varying load condition may be a loading condition or a unloading condition.

[0033] The loading condition may include an increase in the load that the adjusting device has to adjust. For example, this occurs if the lever arm increases and additional weight is loaded onto the adjusting device via this lever arm by the flap (the drive motor will then have a higher load). The motor parameter that changes thereby is the motor current. In the loading condition, this motor current increases. Thus, if the motor current increases, the varying load condition can be determined as a loading condition. Optionally, the adjustment speed can be determined to determine the varying load condition as a loading condition. This adjustment speed decreases contrary to the increase in the motor current.

[0034] The unloading condition may include a decrease in the load that the adjusting device has to adjust. For example, this occurs if the additional weight loaded on the flap weight decreases. For example, in the case of a load in the form of snow, this may mean that the snow slides off the flap. Such a sliding occurs especially when adjusting the flap and thus the snow slides. The determination of the unloading condition can be used to prevent dangerous situations that may be caused by unloading. If the motor current decreases, the varying load condition can be determined as an unloading condition. Optionally, the adjustment speed can be determined to determine the varying load condition as an unloading condition. This adjustment speed increases contrary to the decrease in the motor current (the flap "jumps" to some extent along the opening movement).

[0035] Determining whether there is a load reduction situation can be carried out as follows, that is, determining whether there is a load situation based on the deviation of at least one first measurement value from a predetermined comparison value. In particular, the deviation of at least one additional measurement value may be different from the deviation of at least one measurement value. For example, the deviation of at least one additional measurement value in the form of a motor voltage may be greater than the deviation of at least one measurement value in the form of a motor voltage. In order to adjust the flap, it is necessary to have the motor voltage at the first time point when at least one additional measurement value is measured or at the first positioning of the flap lower than the motor voltage at the second time point when at least one measurement value is measured or at the second positioning of the flap. If the difference in deviations exceeds a predetermined tolerance threshold, it can thus be determined that there is a load reduction situation (for example, this is because the snow accumulated on the flap at the first time point has slipped off at the second time point).

[0036] In a design, it is determined whether a varying load situation is a load reduction situation and the opening movement is braked in case of a load reduction. This design is based on the idea that in case of a sudden load reduction, the flap may move in a jerky manner, which can pose a dangerous situation for the user. The jerky movement can be avoided proactively by braking.

[0037] In a design, in response to determining the existence of a load situation, a warning signal is output to the user of the flap via a warning unit. For example, the warning unit can be set up and configured to emit optical and / or acoustic signals. In particular, the warning unit can include a spindle drive with a spindle, which is set up to adjust the flap and can generate sounds, as described in DE 10 2019 124 064 A1. The user can be requested to remove the additional weight via the warning signal in order to avoid a dangerous situation.

[0038] In a design, at least one motor parameter is predetermined by a regulation unit. The regulation unit can be, for example, a PID regulator. It can regulate the adaptive adjustment of at least one motor parameter so as to always provide the most appropriate adjustment force for adjusting the flap.

[0039] In a further design, the total slope that the regulation unit can preset for at least one motor parameter is limited to a total slope limit value, and / or the sub-slopes that the PID regulator can preset for the P component, I component, and / or D component of at least one motor parameter are limited to their respective sub-slope limit values. Then, if the regulation unit has exhausted the total slope limit value and / or at least one sub-slope limit value, a load condition can be determined to exist. The total slope limit value and / or at least one sub-slope limit value can be preset in such a way that a regulation margin is defined for the regulation unit (thereby avoiding designing the regulation unit at the boundary value). The regulation unit can be established and configured to: be able to cause an excess of the total slope limit value and / or at least one sub-slope limit value, and thus exhaust the regulation margin, in order to preset at least one motor parameter (correspondingly higher than the limit value or with a larger step). However, exceeding the limit value will put the user of the regulating device in a dangerous situation. Different from this regulation margin, there is an optionally set regulation margin when regulating the motor voltage, which can be set to not use all the battery voltage for the operation (especially the acceleration) of at least one drive motor during the normal operation of the regulating device, thereby limiting the motor voltage.

[0040] In the case of a powerful drive motor, it may not be easy to exhaust the total slope limit value and / or at least one sub-slope limit value, so the holding force that can be applied to hold the flap will play a decisive role in determining whether there is a dangerous situation in the load condition (it is usually still possible to adjust the flap with a powerful drive motor). In the case of a powerful drive motor, determining whether there is a load condition is preferably carried out via the deviation of at least one measured value from a preset comparison value in order to improve the reliability of the determination.

[0041] In the case of a weak drive motor, exhausting the total slope limit value and / or at least one sub-slope limit value can already be evaluated as a relatively reliable sign of the existence of a load condition. Then, it is not absolutely necessary to additionally determine the deviation of at least one measured value from a preset comparison value (although this still improves the accuracy of determining the load condition). In this regard, using the regulation unit to determine the existence of a load condition can be carried out independently and regardless of the determination based on the deviation of at least one motor parameter.

[0042] The control unit is established and configured to: regulate the motor speed such that when the opening movement is performed, the standard curve of the motor speed can be appropriately tracked. In particular, the control unit for tracking can be calibrated for tracking under the condition of a maximum voltage of the battery that is reduced compared to the normal condition (room temperature). For example, for this purpose, the PID controller can be set to a predetermined value for at least one motor parameter without additional weight at -35°C. If there is a load condition, the PID controller can adaptively adjust the regulation depending on the magnitude of the determined deviation. For example, if the load is quite small, such an adaptive adjustment is beneficial. Alternatively, if due to a quite large load, further adjustment would put the user in a dangerous situation, the movement can be stopped.

[0043] According to a second aspect of the proposed solution, an adjustment device for adjusting a flap of a motor vehicle, in particular a tailgate or a front luggage compartment lid, is provided. The adjustment device has at least one drive motor and an electronic control unit. The adjustment force for adjusting the flap can be generated via the drive motor. The electronic control unit is established and configured to: determine at least one motor parameter of the drive motor during the opening movement of the flap in order to obtain at least one measured value of at least one motor parameter, determine the deviation between the at least one measured value and a predetermined comparison value, and determine whether there is a load condition based on the deviation.

[0044] The adjustment device can be designed according to the features and advantages stated in connection with the first aspect of the proposed solution.

[0045] The proposed solution also relates to a computer program product having instructions that, when implemented by at least one processor of an electronic control unit of an adjustment device for adjusting a flap of a motor vehicle, in particular a tailgate or a front luggage compartment lid, will cause the at least one processor to implement the method according to the first aspect.

[0046] Furthermore, the proposed solution also relates to a motor vehicle having an adjustment device for adjusting a flap of the motor vehicle according to the second aspect of the proposed solution. Description of the Drawings

[0047] The drawings exemplarily illustrate possible implementation variants of the proposed solution.

[0048] Figure 1 A side view of a motor vehicle with a flap is shown;

[0049] Figure 2 A schematic view of the adjustment device is shown;

[0050] Figure 3Shows a schematic diagram of the measured value of the motor speed changing over time and the associated comparison curve; and

[0051] Figure 4 Shows a schematic diagram of the measured value of the motor voltage changing over time and the associated comparison curve. Detailed implementation

[0052] Figure 1 Shows a side view of a motor vehicle, which has a loading space ("front trunk" or front luggage compartment) arranged at the front part of the motor vehicle. The loading space can be closed by a flap K in the form of a front trunk lid. Here, the flap K can be adjusted between a closed position closing the loading space and an open position opening the loading space, so that the user can (comfortably) access the loading space. During the adjustment from the closed position to the open position, the flap K performs an opening movement along an adjustment stroke R. The progress of the flap K along the adjustment stroke R during the opening movement can be given in the form of an opening angle W.

[0053] The adjustment of the flap K is carried out by an adjustment device 1. Currently, a load L in the form of snow is arranged on the flap K, which causes an additional weight to the weight of the flap K. Via the adjustment device 1, this additional weight must be moved together with the flap K in order to adjust the flap K to the open position. Here, if the load L is particularly large, the adjustment device 1 may be overloaded. In addition, if the load L slides laterally and / or backwards from the open or semi-open flap K, the user of the loading space may be injured by the load L, or the load L may enter the loading space. In order to hold the flap K, a holding force needs to be applied by the adjustment device 1. The holding force may be less than the adjustment force for adjusting the flap K, so that the flap K may automatically close from the open position under the action of the load L, thus pinching the user.

[0054] The adjustment device 1 is set up and configured to determine a load situation in which an additional load needs to be moved. The adjustment device also includes a warning unit 14. When there is a load situation, the warning unit 14 can be used to issue a warning to the user. For this purpose, the warning unit 14 can, for example, emit an acoustic and / or visual signal. In some cases, the load situation can also include improper use of the flap K, for example when the user fastens the load L to the flap K. Additionally or optionally, the warning unit 14 can include an interface with the on-board computer of the motor vehicle, via which information about the load situation, especially information about the improper use of the flap K, can be forwarded to the on-board computer.

[0055] Figure 2A schematic view of the adjusting device 1 is shown. The adjusting device 1 has a drive motor 11, and an adjusting force for adjusting the flap K can be generated via the drive motor. The flap K can be a front luggage compartment lid or a tailgate here. The adjusting device 1 further includes an electronic control unit 12. The electronic control unit 12 has a rotational speed determiner 121 for determining the motor rotational speed of the drive motor 11, a voltage determiner 122 for determining the motor voltage of the drive motor 11, and a current determiner 123 for determining the motor current of the drive motor 11. The electronic control unit 12 determines these three motor parameters of the drive motor 11 at least at one time point or continuously during the opening movement of the flap K in order to obtain measurement values of the motor parameters respectively. In addition, the electronic control unit 12 also determines the deviation between the measurement value and a predetermined comparison value. Based on this deviation, the control unit 12 then determines whether a load situation exists. Here, the electronic control unit 12 can also only determine one of the motor parameters or only determine two of the motor parameters in order to be able to determine whether a load situation exists.

[0056] The adjusting device 1 further has a regulation unit 13, and the motor parameters of the drive motor 11 are regulated by using this regulation unit. Here, the regulation unit 13 is set up and configured to achieve an opening movement through the flap K within a predetermined adjustment duration. The regulation unit 13 makes corresponding predeterminations for the drive motor 11 with respect to the motor parameters. The regulation unit 13 has a proportional-integral-derivative regulator (PID regulator) 133, which has a P regulator 133, an I regulator, and a D regulator.

[0057] In order to perform regulation, the limit can be predetermined in the following way, that is, the regulation unit 13 has a regulation margin. The new predetermination of the motor parameters is restricted by the limit with respect to the current motor parameters. A feasible solution for predetermining the limit is, for example, to limit the total slope that the regulation unit 13 can predetermine for the motor parameters to a total slope limit. Alternatively or additionally, the sub-slope that each regulator of the regulation unit 13 can predetermine can be limited to its respective sub-slope limit (for example, the P component can be limited to avoid large steps). In addition, these limits can be predetermined in such a way that when the regulation unit 13 has exhausted its respective limits, it can be assumed that a load situation exists. Exhausting this limit is another feasible solution for determining whether a load situation exists in addition to determining the deviation between the measurement value and the comparison value. Determining the existence of a load situation can be performed at one or more time points during the opening movement of the flap K.

[0058] The adjusting device 1 further has the warning unit 14 already combined Figure 1 as described in, and a warning can be issued to the user by using this warning unit when a load situation occurs.

[0059] Figure 3A schematic diagram showing the measured value of the motor speed and the comparison curve in the form of a standard curve 31 as a function of the adjustment duration is shown. The control unit 13 presets the motor parameters in such a way that the motor parameters approach the standard curve 31. The control unit 13 controls the motor parameters in such a way that an intersection with the standard curve 31 occurs during the approach.

[0060] For example, the no-load curve 32 is shown in the schematic diagram, which shows the motor speed when adjusting the flap K without load L. At a defined evaluation time point (for example, at 0.2 seconds or when the opening angle W is 1°), the deviation between the measured value on the no-load curve and the predetermined motor speed located on the standard curve 31 is determined. Based on this deviation, it is determined whether a load condition exists. For example, the no-load curve 32 is initially closer to the standard curve 31 than the load curve 33, and the load curve shows the motor speed when adjusting the flap K with load L. Based on the different spacings of the load curve 33 and the no-load curve 32 from the standard curve 31, that is, the deviation between the curves from each other, the load condition can be identified.

[0061] Starting from the point where the no-load curve 32 has a spacing from the standard curve 31, the control unit 13 increases the motor speed so that the no-load curve 32 (towards higher values of the motor speed) intersects the standard curve 31 and draws an arc above the standard curve 31, while at the same time the motor speed is decreased again by the control unit 13 in the direction of the standard curve 31. After the no-load curve 32 (towards lower values of the motor speed) intersects the standard curve 31 for the second time, the no-load curve draws an arc below the standard curve 31, where the spacing from the standard curve 31 at this time is reduced relative to the initial spacing, so that the no-load curve 32 finally approaches the standard curve 31. The approach is also achieved for the load curve 33, where the two arcs made by the load curve 33 with respect to the standard curve 31 are larger than the two arcs in the no-load curve.

[0062] The defined evaluation time point can be selected, for example, in such a way that the evaluation time point is arranged at the intersection of the no-load curve 32 and the standard curve 31. If there is no load condition, the deviation is zero or at least very small. In the case of a load condition, there is a discernible larger deviation because the regulation unit 13 is not yet able to adjust the motor speed high enough at the evaluation time point. Alternatively, the evaluation time point can be arranged in time before the intersection of the no-load curve and the standard curve 31. Determining whether there is a load condition can be performed here based on a deviation of the following form, i.e., determining whether the difference between the standard curve 31 and the measured motor speed value is below a predetermined value. Determining it early in time can advantageously enable an earlier determination of whether there is a load condition. Reacting to the determination that there is no load condition, it is then not necessary to further measure at least one motor parameter. In addition, the adjustment can also be performed faster by, for example, increasing the adjustment speed used for the adjustment flap K from the evaluation time point onwards.

[0063] It can also be seen from the schematic diagram that the area between the standard curve 31 and the no-load curve 32 is smaller than the area between the standard curve 31 and the load curve 33. In view of this, it is also possible to achieve the goal by performing the determination of the deviation in such a way that an integral difference between the respective measured curve and the comparison curve in the form of the standard curve 31 is performed. Thereby, the degree to which the motor speed lags behind the comparison value can be determined over a period of time starting from the opening movement.

[0064] In principle, it is also conceivable and feasible to consider the slope of the motor speed to determine the deviation from the standard curve 31. Since the regulation causes the no-load curve 32 to fluctuate around the standard curve 31, this is particularly achievable at the start of the opening movement (e.g., during the initial 500 ms). Here, the force that must be overcome to break free from the stationary state, such as the adhesion force on the seal of the flap K, can be incorporated into the assessment of the slope.

[0065] The schematic diagram exemplarily shows an overload curve 34, which represents a situation where the load L acting on the flap K is so excessive that initially (due to the low motor voltage), no movement can occur at all. A comparison curve in the form of a standard curve 31 prescribes the increase from a first motor speed RPM1 (e.g., 800 revolutions per minute) to a second motor speed RPM2 (e.g., 1200 revolutions per minute), while the overload curve 34 reflects no movement at all (0 revolutions per minute). Only after approximately 2 seconds does the drive motor 11 apply sufficient power to achieve a slight increase in the motor speed. The regulation is mainly determined by the P component here because the spacing between the standard curve 31 and the overload curve 34 is very large. Here, the overload curve 34 rises linearly in a straight line. In this case, although the opening movement is possible, the user will be in a dangerous situation due to the opening movement because the regulating device 1 may not be able to hold the flap K in the intermediate position between the open position and the closed position, so if the flap K closes accidentally under the action of the load L, the user is at risk of being pinched. Determining such a load situation can be carried out, for example, based on the deviation between the overload curve 34 and the standard curve 31, which is greater than the deviation in the case of the no-load curve 32 and the load curve 33. Therefore, the regulating device 1 can output a warning signal to the user, stop the opening movement, and / or return the flap K to the closed position in order to protect the user and the drive motor 11.

[0066] Figure 4 A schematic diagram showing the measured value of the motor voltage and a comparison curve in the form of a maximum curve 41. The motor voltage varies here between a first motor voltage and a second motor voltage. The second motor voltage is higher than the first motor voltage. The value of the second motor voltage is related to the temperature of the vehicle's battery. For example, when the temperature drops from room temperature (under normal conditions) to -35 °C, the second motor voltage drops from 16.0 V to 10.5 V. Therefore, at a lower temperature (e.g., where there is also likely to be a snow load at this lower temperature), less power is available for the drive motor 11 of the regulating device 1. Therefore, it can be advantageous to configure the regulating unit in such a way that the desired opening movement can be achieved at -35 °C (especially in view of the regulation duration and the regulation speed).

[0067] The maximum curve 41 describes the maximum voltage at which the regulating device 1 can be used to regulate the flap K during the opening movement. In the initial stage, the maximum curve rises linearly from the first motor voltage to the second motor voltage. After the rise, the maximum voltage is supplied to the regulating device 1.

[0068] The no-load curve 42 shows the course of the motor voltage during the opening movement of the flap K without additional load L. To accelerate the flap K to a constant regulated speed, the motor voltage initially rises linearly in part, then reaches a maximum, and then drops again to a substantially constant value. The rise and fall are completed in about 3 seconds. The no-load curve 42 of the motor voltage corresponds to the no-load curve 32 of the motor speed. The initial rise of the motor voltage results in a rise in the motor speed and the first section of the motor speed curve here. If the motor voltage drops after the maximum, the motor speed also decreases accordingly.

[0069] The spacing between the maximum and the maximum voltage defines the (pulse width modulation) regulation margin, which is reserved by the regulation unit 13 to provide a margin for acceleration. Thus, the regulation unit 13 can be designed not at the boundary value in such a way that it always utilizes up to the maximum voltage. This design allows the use of the regulation margin in the presence of a load situation in order to reach the regulated speed of the flap K with the same acceleration, so that during the execution of the opening movement, as constant a usage experience of the flap K as possible is provided for the user (regardless of whether there is a load situation or not). Thus, at the end of the motor voltage rise phase, the maximum of the load curve 43 touches the maximum curve 41. Thereby, the target speed is also reached during the initial phase of the opening movement (cf. Figure 3 the load curve 33 corresponding to the load curve 43 in, which intersects the standard curve 31). Due to reaching the target speed, the deviation of the P component of the PID regulation in the load curve 33 of the motor speed will remain low despite the intersection and the arc (numerically, this curve is closer to the standard curve 31 than Figure 3 the overload curve 34 in). In this situation, the regulation is mainly carried out via the I component of the PID regulator 133. For this purpose, the total regulation margin will be exhausted (the total slope limit and at least the sub-slope limit of the I component are exhausted).

[0070] In contrast, the maximum voltage is always required in the overload curve 44 of the motor voltage. Given Figure 3 the motor speed in, the P component of the regulation also needs to make a rather large contribution here, because the distance between the standard curve 31 and the overload curve 34 of the motor speed is very large. Thus, in particular, it can be determined from the exhaustion of the regulation margin that there is a load situation with regulation of overload, because the total slope limit and in this case especially the sub-slope limit for the P component are exhausted.

[0071] Therefore, especially during the initial phase of the opening movement (during which the flap K accelerates from the closed position in the direction of the open position), the deviation of the measured motor voltage from the maximum voltage during the opening movement can be used to determine the presence of a load condition by determining whether the deviation is zero or at least less than a predetermined threshold.

[0072] List of reference signs

[0073] 1 Adjusting device

[0074] 11 Driving motor

[0075] 12 Control unit

[0076] 121 Rotational speed determiner

[0077] 122 Voltage determiner

[0078] 123 Current determiner

[0079] 13 Regulation unit

[0080] 131 P regulator

[0081] 132 I regulator

[0082] 133 D regulator

[0083] 14 Warning unit

[0084] 31 Standard curve

[0085] 32 No-load curve

[0086] 33 Load curve

[0087] 34 Overload curve

[0088] 41 Maximum curve

[0089] 42 No-load curve

[0090] 43 Load curve

[0091] 44 Overload curve

[0092] K Flap

[0093] L Load

[0094] R Adjustment stroke

[0095] W Opening angle

Claims

1. A method for adjusting a flap (K) of a motor vehicle, in particular a tailgate or a front luggage compartment lid, by means of an adjusting device (1), the method comprising the following steps: - initiating an opening movement of the flap (K), - determining at least one motor parameter of a drive motor (11) of the adjusting device (1) during the opening movement in order to obtain at least one measured value of the at least one motor parameter, - determining a deviation of the at least one measured value from a predetermined comparison value, and - determining whether a load condition exists based on the deviation.

2. The method according to claim 1, wherein The load condition includes a situation in which the sum of the self-weight of the flap (K) and an additional weight additionally loaded on the flap (K) exceeds a predetermined maximum weight.

3. The method according to claim 1, wherein Performing an adaptive adjustment of at least one motor parameter in a first load condition and stopping the opening movement in a second load condition.

4. The method according to claim 1, wherein Determining the at least one measured value within the first third of an adjustment travel (R) traversed by the flap (K) during the opening movement, or determining the at least one measured value within the first third of an adjustment duration traversed by the flap (K) during the opening movement.

5. The method according to claim 1, wherein The at least one motor parameter includes a motor speed, a motor voltage or a motor current.

6. The method according to claim 1, characterized in that, Determining the deviation includes: - determining the difference between the at least one measured value and the predetermined comparison value, - determining the area difference between a measurement curve passing through at least two measured values and a comparison curve passing through the predetermined comparison value, and / or - determining the difference in the slopes of the measurement curve and the comparison curve.

7. The method according to claim 5, characterized in that, Determining the deviation includes: - determining the difference between the at least one measured value and the predetermined comparison value, - determining the area difference between a measurement curve passing through at least two measured values and a comparison curve passing through the predetermined comparison value, and / or - determining the difference in the slopes of the measurement curve and the comparison curve, wherein determining the deviation of the motor voltage includes determining the difference between at least one measured value of the motor voltage and a predetermined comparison value in the form of the maximum voltage of a battery of the motor vehicle.

8. The method according to claim 1, characterized in that, Determining whether a load condition exists is based on the deviations determined for at least two motor parameters.

9. The method according to claim 1, wherein Having: determining at least one further measured value of the at least one motor parameter, determining the deviation of the at least one further measured value from a predetermined comparison value, comparing the deviations of the at least one measured value and the at least one further measured value from their respective comparison values and determining whether a variable load condition exists based on this comparison.

10. The method according to claim 9, wherein Determining whether the variable load condition is a load reduction condition and braking the opening movement in a load reduction condition.

11. The method according to claim 1, wherein In response to determining that a load condition exists, outputting a warning signal to a user of the flap (K) via a warning unit (14).

12. The method according to claim 1, wherein Predetermining the at least one motor parameter by means of a regulation unit (13).

13. The method according to claim 12, characterized in that: - Limit the total slope that the control unit (13) can specify for the at least one motor parameter to a total slope limit, and / or limit the sub-slopes that the PID controller (133) of the control unit (13) can specify for the at least one motor parameter for the P component, I component, and / or D component to their respective sub-slope limits, - Determine that a load condition exists when the control unit (13) has exhausted the total slope limit and / or at least one sub-slope limit.

14. An adjusting device for adjusting a flap (K) of a motor vehicle, in particular a tailgate or a front luggage compartment lid, the adjusting device having at least one drive motor (11) and an electronic control unit (12), via which drive motor an adjusting force for adjusting the flap (K) can be generated, the electronic control unit being configured and arranged for: - Determine at least one motor parameter of the drive motor (11) during the opening movement of the flap (K) in order to obtain at least one measured value of the at least one motor parameter, - Determine the deviation of the at least one measured value from a predetermined comparison value, and - Determine based on the deviation whether a load condition exists.

15. A computer program product having instructions which, when implemented by at least one processor of an electronic control unit (12) of an adjusting device (1) for adjusting a flap (K) of a motor vehicle, in particular a tailgate or a front luggage compartment lid, will cause the at least one processor to implement the method according to any one of claims 1 to 13.

16. A motor vehicle having an adjusting device (1) for adjusting a flap (K) of the motor vehicle according to claim 14.

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