Speed control update rate slows down

Abstract

An open roof construction for use in a roof of a vehicle, comprising a movably arranged closing member, an electric motor for moving the closing member, an electric drive unit for providing a power signal to the electric motor, and a pinch control module operatively coupled to the electric drive unit for controlling operation of the electric motor in a pinch event. The pinch control module comprises at least a PWM controller capable of providing a duty cycle. The pinch control module is configured to calculate a pinch force signal based on input of measured data, to cause a safe stop of the closing member in a pinch event when the calculated pinch force signal exceeds a first pinch threshold during a closing operation of the closing member, and to cause an immediate reversal of a polarity of the power signal provided by the electric drive unit to the electric motor. The pinch control module is configured to have a second threshold, which is set to a level lower than the first threshold, the second threshold marking a beginning of a suspected pinch event.

Description

Technical Field

[0001] This invention relates to an open roof structure for vehicles. Background Technology

[0002] Such open roof structures are known in the prior art. For many years, anti-pinch control has been used in open roof structures to prevent pinching events between the closure member and the edge of the roof opening. The pinch control module may include a PWM (Pulse Width Modulation) controller, and the pinch control module calculates a pinch force signal based on input measured data. During a pinch event, the calculated pinch force signal may exceed a certain threshold, at which point the pinch control module is triggered to send a signal to the electric drive unit for reversing the electric motor and thus for reversing the closure member. Because the movement speed of the closure member is kept constant by the PWM controller, and because the speed of the closure member decreases due to resistance after the pinch begins, the PWM controller may increase the speed again by updating the duty cycle to, for example, 100%, which may affect the anti-pinch performance of the open roof structure. Summary of the Invention

[0003] In view of the above, the object of the present invention is to solve the above problems and to provide an improved clamping control module for open roof structures.

[0004] According to the present invention, the open roof structure is characterized by the features of the characteristic portion.

[0005] According to one aspect of the invention, the pinch control module is configured to have a second threshold, which is set to a level lower than the first threshold, the second threshold marking the start of a suspected pinch event. However, it is also conceivable that the pinch control module is configured to modify the update of the duty cycle of the PWM controller when the second threshold is exceeded, wherein the duty cycle remains constant to reduce the speed of the moving enclosing member.

[0006] Advantageously, at the onset of a pinch event, the duty cycle is modified so that it does not attempt to increase but remains at a constant level, thus reducing the speed of the closing member instead of increasing. This increases the time the pinch control module has to detect pinching.

[0007] According to another aspect of the invention, the second threshold is configured such that the clamping force signal used for calculation is in the range of 15 N to 40 N, more preferably 25 N. Advantageously, the second threshold is set not too low to avoid any of these phenomena exceeding the second threshold and thus initiating clamping under any minimal increase in resistance faced by the mechanical drive system. However, it is also advantageous not to set the second threshold too high, as this would reduce the time gain for the clamping control module to detect clamping. Thus, it is conceivable to set the second threshold within the range described above.

[0008] According to another embodiment of the invention, the pinch control module is configured to update the duty cycle of the PWM controller to a lower constant value when a second threshold of a suspected pinch event is exceeded, thereby reducing the speed of the moving closing member. However, according to another embodiment, it is also conceivable that the pinch control module is configured to reduce the duty cycle of the PWM controller in a linearly decreasing manner when the calculated pinch force signal exceeds the second threshold.

[0009] To maximize the time between exceeding the second threshold and exceeding the first threshold, it is conceivable to reduce the duty cycle update to a constant level lower than the update when the second threshold is exceeded, or to reduce the duty cycle in a linearly decreasing manner. Both methods increase the time for the pinch control module to detect pinching, and further enhance the robustness of the anti-pinch system. For example, this robustness is increased because the calculated pinch force signal can prevent unnecessary exceedances of the first threshold (false anti-pinch) when the mechanical drive assembly encounters resistance while moving the closing member to the closed position and when the second threshold is exceeded. In such a case, the closing member will neither come to a complete stop nor reverse.

[0010] In another embodiment, it is also conceivable that the clamping control module is configured to reduce the duty cycle of the PWM controller based on the steepness of the increase in the clamping force signal value calculated before the clamping force signal exceeds the second threshold. An advantage here is that by setting the reduction in the duty cycle based on the steepness of the increase in the clamping force signal calculated before the calculated clamping force signal reaches the second threshold, the system can be made more robust. This can be interpreted as the duty cycle being reduced between the second and first thresholds when the calculated steepness of the increase in the clamping force signal is high, so that the maximum reduction in time before the clamping force signal exceeds the first threshold can be achieved.

[0011] According to another aspect of the invention, the clamping control module is configured to change the update of the duty cycle of the PWM controller such that when the calculated clamping force signal is lower than the second threshold, the electric drive unit provides an adaptation signal to the electric motor, the adaptation signal controlling the closing member to move at a constant speed. According to yet another aspect of the invention, the clamping control module is configured to calculate the clamping force signal based on measured data from a set of data including measurements of the speed change of the closing member, battery voltage, vehicle speed, ambient temperature, motor speed, the position of the closing member in the roof opening, and motor current.

[0012] To achieve a constant speed for the closing member during opening and closing, the clamping control module is configured to continuously calculate a clamping force signal based on measured data. When the measured data value changes, the clamping control module calculates a changed clamping force signal output. This changed clamping force signal output can cause an adjustment to the duty cycle of the PWM controller when the clamping control signal exceeds a second threshold, thereby maintaining a substantially constant speed for the closing member. The speed of the closing member changes unless one of the second or first thresholds is exceeded.

[0013] According to another aspect of the invention, the clamping control module is configured to continuously calculate a clamping force signal based on continuously measured data, and wherein when the calculated clamping force signal recovers from a value above a second threshold to a value below the second threshold, the clamping control module resumes to maintain the closing member at a constant speed. In the event of exceeding the second threshold and a change in duty cycle, the calculated clamping force signal can recover to a value below the second threshold. This may occur, for example, when mechanical resistance in the mechanical drive assembly is input to the clamping control module via measured data and the clamping signal exceeds the second threshold. The closing member moves further at a modified speed, and when, for some reason, the resistance no longer exists and the calculated clamping signal recovers to a value below the second threshold, the closing member will return to the speed prior to the mechanical interruption.

[0014] According to another aspect of the invention, a method is defined for detecting a pinching event of a movablely arranged closed member for an open roof structure in a vehicle roof, the method comprising the steps of:

[0015] a. Provide the measured data to the clamping control module.

[0016] b. The clamping control module calculates the clamping force signal based on the input measured data.

[0017] c. The clamping force signal is compared with a second threshold using the clamping control module.

[0018] d. An additional step is defined as follows: when the clamping force signal exceeds the second threshold, the PWM duty cycle is modified using the PWM controller.

[0019] e. The additional step is defined as: comparing the calculated clamping force signal with a first threshold using the clamping control module, and

[0020] f. When the clamping force signal exceeds the first threshold, the clamping control module, the electric drive unit, and the electric motor are used to cause the sealing member to stop and reverse safely.

[0021] According to another aspect of the invention, step d is: starting from the moment when the calculated clamping force signal exceeds the second threshold, the PWM duty cycle is maintained at a constant level using the PWM controller.

[0022] According to another embodiment of the present invention, step d is: when the calculated clamping force signal exceeds the second threshold, the duty cycle is reduced to a lower constant level using the PWM controller.

[0023] According to another embodiment of the present invention, step d is: when the calculated clamping force signal exceeds the second threshold, the duty cycle of the PWM controller is reduced in a linearly decreasing manner.

[0024] According to another aspect of the invention, in step a, the measured data comes from a set of data including measurements of the speed change of the closure member, battery voltage, vehicle speed, ambient temperature, motor speed, the position of the closure member in the roof opening, and motor current.

[0025] Furthermore, according to another aspect of the invention, in step f, an additional threshold of time constraint F is used, wherein after time constraint F expires and the calculated clamping force signal does not exceed the first threshold, the step of restoring the PWM duty cycle prior to clamping detection begins. Attached Figure Description

[0026] Figure 1 A schematic isometric view of a vehicle with an open roof structure.

[0027] Figure 2 This is a schematic exploded view of the open roof structure according to the present invention.

[0028] Figure 3A This is a schematic diagram illustrating the basic components of the present invention.

[0029] Figure 3B This is a schematic diagram illustrating the steps of a method for detecting pinch events.

[0030] Figure 4 The diagram illustrates the coherence between clamping force, PWM duty cycle, and closing member speed during a clamping event in the prior art.

[0031] Figure 5 , 6 Figures 7 and 8 are combined schematic diagrams, which illustrate the coherence between the clamping force, PWM duty cycle, and closing member speed during the clamping event in the first, second, third, and fourth embodiments.

[0032] Figure 9 The diagram illustrates the coherence between clamping force, PWM duty cycle, and closing member velocity during a spurious clamping event. Detailed Implementation

[0033] Figure 1 An open roof configuration for a vehicle roof 1 is shown. The open roof configuration includes a closure member 2, shown in its open position, wherein the closure member 2 has moved from a closed position within a roof opening 3 above the roof surface to a rear position above the roof 1. The closure member 2 is also movable to an inclined position, wherein the rear edge of the closure member 2 is raised above the roof surface. The closure member 2 shown is a translucent glass panel, and below the open closure member 2, a second translucent glass panel is shown, which may be a fixed panel. This fixed panel covers the rear portion of the opening 3 in the roof 1.

[0034] Such fixed panels are directly attached to the frame of the open roof structure, or attached to the vehicle's fixed roof 1. It is conceivable that the rear window panel is also operable.

[0035] The open roof structure further includes a mechanical drive assembly 5 and an electric motor 4, which together move the closing member 2 from a closed position to at least a partially open position, in which the opening 3 of the roof 1 is closed.

[0036] When the closing member 2 moves from the open position to the closed position, the movement of the closing member 2 is controlled by the pinch detection system. The pinch detection system described in this document is the pinch control module 7, which is a system required to prevent objects (such as hands or fingers) from being pinched between the closing member 2 and the edge of the opening 3 in the roof 1.

[0037] Figure 2A schematic exploded view of the open roof structure is shown, with a movable closure member 2 and a rear glass panel shown at the top, and a mechanical drive assembly 5 (in a very schematic manner) including an electric motor 4 and an electric drive unit 6. Further below, the frame of the open roof structure, which can be attached to the vehicle body (the latter not shown), is shown schematically.

[0038] Figure 3A The electrically driven unit 6, with a pinch control module 7, is shown in more schematic detail. The pinch control module 7 includes a PWM controller 8 and a gateway for receiving measured data for use in the pinch control module 7. The PWM controller 8 is capable of generating a duty cycle 9.

[0039] The clamping control module 7 is configured to calculate a clamping force signal 10 based on measured data from a set of data, including: measured values ​​of the velocity change of the closure member 2, the position of the closure member 2 in the roof opening 3 of the open roof structure, battery voltage, vehicle speed, ambient temperature, motor speed, or current from the motor. In calculating the clamping force signal 10, the signal 10 is compared with a first threshold 11 to determine clamping. When the clamping force signal 10 exceeds the first threshold 11, the clamping control module 7 generates a signal to the electric drive unit 6, which immediately reverses the polarity of the electric motor 4, causing the closure member 2 to reverse, thus ending the clamping event.

[0040] exist Figure 3B The diagram illustrates the steps of a method for detecting pinch events. Measured data is sent to a pinch control module 7, which calculates a pinch force signal 10. The calculated pinch force (CPF) signal 10 is compared to a second threshold 12, and if it exceeds the second threshold 12, the PWM controller 8 modifies the duty cycle 9 at time t1. This modification of the duty cycle 9 can be to keep the level of duty cycle 9 constant and the same as at time t1, or it can be to reduce the duty cycle 9 compared to its level at time t1 and keep it constant, or it is conceivable to reduce the duty cycle 9 in a linear or non-linear manner compared to its value at time t1. Furthermore, the reversal of the closing member 2 is evident when the CPF signal 10 exceeds a first threshold 11 within a time limit F. If the CPF signal 10 does not exceed the first threshold 11 within the time limit F, the PWM duty cycle 9 will return to "normal," i.e., as it was before time t0.

[0041] Figure 4 A schematic diagram is shown, which explains the coherence between clamping force, clamping force threshold 11, PWM duty cycle 9 and the speed of the closed component for the open roof structure of the prior art.

[0042] During a pinching event, meaning from the start of the pinching event until the reversal threshold (i.e., the first threshold 11) is exceeded, the speed of the closing member 2 remains constant through the duty cycle 9. This means that due to the resistance of the pinched object and the requirement for the PWM controller 8 to maintain a constant speed of the closing member 2, the duty cycle 9 of the PWM controller 8 increases. The duty cycle 9 cannot increase further only if it reaches 100% before reaching the reversal threshold (first threshold 11). Figure 4 As shown, the time at which the clamping begins is t0, and the time exceeding the first threshold 11 is t2. Therefore, the difference between t0 and t2 is the time required to determine whether a real clamping event exists and to begin the reversal of the closing member 2.

[0043] Figure 4 The duty cycle 9 before t0 in the middle is set to a constant level, and in Figure 4 The duty cycle 9 is shown as a straight line. However, in practice, the duty cycle 9 will not be a straight line because the mechanical drive assembly 5 will experience a continuous change in resistance as the closing member 2 slides toward the closed position. However, for clarity, these small changes are ignored in the figures presented in this document, and the PWM duty cycle 9 is shown as a straight line or a curve, depending on the specific figures.

[0044] In the behavior of existing clamping detection systems, the diffusion of mechanical resistance plays a significant role. The resistance of the mechanical drive assembly 5 affects clamping detection. Specifically, when the mechanical drive assembly 5 encounters higher resistance when sliding the closing member 2 to the closed position, the PWM duty cycle percentage 9 is also relatively high. This means that when clamping begins at t0, the duty cycle 9 increases to maintain a constant speed for the closing member 2. However, because the update of the duty cycle 9, starting from a high percentage level, quickly reaches 100% and the update of the PWM duty cycle 9 cannot increase further than 100%, this means that the speed of the closing member 2 will slow down before reaching the reversal threshold (first threshold 11). In this case, the resistance of the mechanical drive assembly 5 is lower, and the duty cycle 9 also operates at a lower level. When clamping begins at t0, the duty cycle 9 will increase to maintain a constant speed for the closing member. However, this could mean that in this case, when the duty cycle 9 is increased as a result, the first threshold 11 may be reached earlier than the duty cycle 9 reaches 100%, and therefore the closing member 2 will be reversed without reducing the speed of the closing member 2 due to reaching the limit of 100% of the PWM duty cycle 9. Both cases indicate that the behavior of the PWM controller 8 will be diffused in various open roof configurations due to the diffusion of mechanical resistance.

[0045] Figure 5A schematic diagram is shown, in which the coherence between clamping force, clamping force thresholds 11 and 12, PWM duty cycle 9 and the speed of the closing member is explained with reference to a first embodiment of the present invention.

[0046] In this embodiment, a second threshold 12 is introduced and set to a clamping force level lower than the first threshold 11, at which the closing member 2 will reverse. The second threshold 12 is set to a clamping force level 10 in the range of 15 N-40 N, preferably 25 N. This second threshold 12 can be used to modify the update of the duty cycle 9 of the PWM controller 8, for example, to keep the duty cycle 9 constant at its level when it exceeds the second threshold 12, or to reduce the update of the duty cycle 9 in a specific manner, for example, as described below.

[0047] like Figure 5 As shown, when the clamping event begins at t0, the PWM duty cycle 9 immediately increases to maintain a constant speed for the closing member 2. At t1, the clamping force signal 10 exceeds the second threshold 12, and the update of the duty cycle 9 is immediately maintained at the level of the duty cycle 9 when the second threshold 12 is exceeded. Because the duty cycle 9 is kept at the same level, the speed of the closing member 2 decreases due to the increased resistance caused by the clamped object and the mechanical resistance of the mechanical drive assembly 5. Therefore, the increase in clamping force slows down until the clamping force signal 10 exceeds the first threshold 11 and the clamping control module 7 causes the closing member 2 to reverse. The slower increase in clamping force results in a longer time for the clamping force signal 10 to exceed the first threshold 11. This... Figure 5 The diagram is shown in the figure, where time t2 from the "prior art" diagram is plotted and where t3 is the time when the pinch force signal 10 exceeds the first threshold 11. Clearly, t3 > t2, thus providing more time to detect the pinch event. By introducing a second threshold 12, the overall pinch detection performance becomes less dependent on the PWM controller 8 and is therefore more stable.

[0048] Figures 6 to 8 The second, third, and fourth embodiments are shown, each illustrating another way in which the level of duty cycle 9 at t1 affects the PWM duty cycle 9 when the calculated pinch signal 10 exceeds the second threshold 12. For example, in Figure 6 In the context of the calculated clamping force exceeding the second threshold 12, the PWM duty cycle 9 decreases to another constant level. The time t2 is taken from a prior art schematic. Clearly, in... Figures 6 to 8 In each of them, t3 > t2 and therefore there is more time to detect squeezing events.

[0049] exist Figure 7In this context, the PWM duty cycle 9 decreases linearly compared to the level of the duty cycle 9 present when the calculated pinch force signal 10 exceeds the second threshold 12. The time t2 is taken from a prior art schematic diagram. Clearly, t3 > t2, and therefore there is more time to detect the pinch event.

[0050] exist Figure 8 In this process, the PWM duty cycle 9 decreases in a manner that depends on the steepness of the increase in the value of the clamping force signal 10, calculated before the clamping force signal 10 exceeds the second threshold 12. For example, by... Figure 8 The diagram illustrates two examples where, in the first example, the calculated pinch force signal 10 exceeds the second threshold 12 at t1, while in the second example, the calculated pinch force signal 10 exceeds the second threshold 12 more quickly at t1'. In the first example, the calculated pinch force signal 10 increases over a longer time period than in the second example. Therefore, in the first example, the PWM duty cycle 9 increases as shown... Figure 7 The method described in the example reduces the PWM duty cycle 9 in a non-linear manner, whereas in the second example (where the second threshold 12 is reached within a shorter time period). The time t2 is taken from a prior art schematic diagram. It is clear that t3 > t2 and t3 > t2', and therefore there is more time to detect the pinch event.

[0051] Figure 9 As shown, the probability of false anti-pinch detection increases because the second threshold 12 for possible pinching is much lower than the first reversal threshold 11.

[0052] Therefore, once the PWM update rate of duty cycle 9 decreases in the manner described above, the clamping force is monitored. If the calculated clamping force signal 10 does not increase above the first threshold 11 within a certain time limit F (at t4), the PWM controller 8 returns to normal operation to control the closing member 2 to move at a constant speed, and thus the direction of movement of the closing member 2 is the same as the direction before the clamping began.

[0053] The present invention is not limited to the embodiments described above, which can be varied extensively within the scope of the invention as defined in the appended claims. For example, it is conceivable that the use of the second threshold 12 is not limited to the detection of pinching of the closure member 2 when it is slid forward to its closed position, but can also be used for the detection of pinching when the closure member 2 is in its inclined position, in which the rear portion of the closure member 2 is positioned above the roof surface and moves downward to the closed position.

Claims

1. An open roof structure for use in the roof (1) of a vehicle, the open roof structure comprising: A movable enclosure (2) for selectively covering or at least partially exposing an opening (3) in the roof (1). An electric motor (4) is operably connected to the enclosed member (2) via a mechanical drive assembly (5) for moving the enclosed member (2). An electric drive unit (6) is used to provide a power signal to the electric motor (4), and A pinch control module (7), operably connected to the electric drive unit (6), for controlling the operation of the electric motor (4) in the event of a pinch, wherein the pinch control module (7) includes at least: A PWM controller (8) capable of providing a duty cycle (9). The clamping control module (7) is configured as follows: -Calculate the clamping force signal based on the measured data (10). - During the closing operation of the closing member, in the event of a pinching incident, when the calculated pinching force signal (10) exceeds a first threshold (11), it causes a safe stop of the closing member (2) and an immediate reversal of the polarity of the power signal supplied by the electric drive unit (6) to the electric motor (4), and - Having a second threshold (12) set to a level lower than the first threshold (11), the second threshold (12) marks the start of a suspected pinching event when the pinching force signal (10) exceeds the second threshold (12), and the duty cycle (9) of the PWM controller (8) is reduced based on the steepness of the increase in the value of the pinching force signal (10) calculated before the pinching force signal (10) exceeds the second threshold (12).

2. The open roof structure according to claim 1, wherein, The second threshold (12) is configured for the calculated clamping force signal (10) in the range of 15 N to 40 N.

3. The open roof structure according to claim 2, wherein, The second threshold (12) is configured for the calculated clamping force signal (10) of 25 N.

4. The open roof structure according to any one of claims 1 to 3, wherein, The clamping control module (7) is configured to update the duty cycle (9) of the PWM controller (8) to a lower constant value when the calculated clamping force signal (10) exceeds the second threshold (12), so as to reduce the speed of the moving closed member (2).

5. The open roof structure according to any one of claims 1 to 3, wherein, The clamping control module (7) is configured to reduce the duty cycle (9) of the PWM controller (8) in a linearly decreasing manner when the calculated clamping force signal (10) exceeds the second threshold (12).

6. The open roof structure according to any one of claims 1 to 3, wherein, The clamping control module (7) is configured to change the update of the duty cycle (9) of the PWM controller (8) when the calculated clamping force signal (10) is lower than the second threshold (12), so that the electric drive unit (6) provides an adaptation signal to the electric motor (4), the adaptation signal controlling the closing member (2) to move at a constant speed.

7. The open roof structure according to any one of claims 1 to 3, wherein, The clamping control module (7) is configured to calculate the clamping force signal (10) based on measured data from a set of data including measurements of the speed change of the closure member, battery voltage, vehicle speed, ambient temperature, motor speed, the position of the closure member (2) in the opening (3), and motor current.

8. The open roof structure according to claim 7, wherein, The clamping control module (7) is configured to continuously calculate the clamping force signal (10) based on continuously measured data, and wherein when the calculated clamping force signal (10) recovers from a value higher than the second threshold (12) to a value lower than the second threshold (12), the clamping control module (7) resumes to keep the closing member (2) at a constant speed.

9. A method for detecting a pinching event of a movablely arranged closure member (2) for use in an open roof structure in a vehicle roof (1), the closure member (2) being used to selectively cover or at least partially expose an opening (3) in the roof (1). The method includes the following steps: a. Provide measured data to the pinch control module (7), wherein the pinch control module (7) includes a PWM controller (8) capable of providing a duty cycle (9); b. The clamping control module (7) is used to calculate the clamping force signal (10) based on the input of the measured data. e. The calculated clamping force signal (10) is compared with the first threshold (11) using the clamping control module (7). f. When the clamping force signal (10) exceeds the first threshold (11), the clamping control module (7), the electric drive unit (6), and the electric motor (4) are used to cause the safe stopping and reversal of the closing member (2), wherein an additional step is defined between steps b and e: c. Using the clamping control module (7), compare the clamping force signal (10) with the second threshold (12), and d. When the clamping force signal (10) exceeds the second threshold (12), the duty cycle (9) of the PWM controller (8) is modified by reducing the duty cycle (9) of the PWM controller (8) based on the steepness of the increase of the value of the clamping force signal (10) calculated before the clamping force signal (10) exceeds the second threshold (12).

10. The method according to claim 9, wherein, Step d is: when the calculated clamping force signal (10) exceeds the second threshold (12), the duty cycle (9) of the PWM controller (8) is reduced to a lower constant level using the PWM controller (8).

11. The method according to claim 9, wherein, Step d is: when the calculated clamping force signal (10) exceeds the second threshold (12), the duty cycle (9) of the PWM controller (8) is reduced in a linear manner.

12. The method according to any one of claims 9 to 11, wherein, In step a: the measured data comes from a set of data, which includes: the measured value of the speed change of the closed member (2), battery voltage, vehicle speed, ambient temperature, motor speed, the position of the closed member (2) in the opening (3), and motor current.

13. The method according to any one of claims 9 to 11, wherein, In step f: using an additional threshold of time limit F, wherein after time limit F expires and the calculated clamping force signal (10) does not exceed the first threshold (11), the step of restoring the duty cycle (9) before clamping detection begins.

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