Driving member control device

The control unit in the drive member device accurately estimates and adjusts motor temperature to prevent overheating by remembering motor temperature during normal power-off and setting a lower operating restriction threshold, addressing the issue of incorrect temperature estimation after abnormal power-off.

JP7622606B2Active Publication Date: 2025-01-28DENSO CORP
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Patent Information

Application Number
JP2021170269
Authority / Receiving Office
JP · JP
Patent Type
Patents
Current Assignee / Owner
Filing Date
2021-10-18
Publication Date
2025-01-28
Estimated Expiration
2041-10-18

AI Technical Summary

Technical Problem

Existing drive member control devices fail to accurately estimate motor temperature when power is turned on after an abnormal power-off event, leading to potential motor overheating and burning due to incorrect temperature settings.

Method used

A control unit that estimates and remembers the motor temperature during normal power-off, adjusts the estimated motor temperature to account for deviations from actual temperature, and sets an operating restriction threshold lower than the maximum to prevent motor overheating by limiting power supply.

Benefits of technology

Prevents motor overheating and burning by accurately estimating and adjusting motor temperature settings, even after abnormal power-off events, ensuring safe operation.

✦ Generated by Eureka AI based on patent content.

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Abstract

To provide a driving member controller which can suppress burning damage of a motor even when control is finished in an abnormal process.SOLUTION: A power window device 2 has a controller 8 for controlling a motor M for driving a window glass 1 and limiting power supply to the motor M in response to the state that an estimated estimation motor temperature has reached an operation limitation threshold value temperature. The controller 8 sets the difference between the operation limitation threshold value and the estimation motor temperature will be less than the maximum value in response to the determination that a control was finished in an abnormal process when the power source is in an on-state last time.SELECTED DRAWING: Figure 1
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Description

[Technical field]

[0001] The present invention relates to a drive member control device. [Background technology]

[0002] Conventionally, some driving member control devices, such as power window control devices, are provided with a control unit that limits power supply to the motor according to an estimated motor temperature, thereby preventing and protecting the motor from burning out (see, for example, Patent Document 1). This driving member control device stores the estimated motor temperature when the power is off, and is capable of estimating the estimated motor temperature at that time based on the estimated motor temperature stored when the power is on. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-106767 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the above-mentioned driving member control device, when the control of the control unit is terminated in an abnormal process, for example, when the battery is removed before the power is turned off in a normal process such as turning off the ignition switch, the estimated motor temperature at that time is not stored. Therefore, when the power is turned on the next time when the ignition switch is turned on, the estimated motor temperature at that time may be estimated based on the old estimated motor temperature stored when the power was turned off in the normal process. Therefore, when the power is turned on after the control is terminated in the abnormal process, for example, an estimated motor temperature that is low and deviates from the actual motor temperature and has dropped to a minimum motor temperature equivalent to room temperature may be set as the current estimated motor temperature. This may cause the motor to continue to operate even when the actual motor temperature is close to the operation limit threshold temperature, and may eventually cause the motor to burn out.

[0005] The present invention has been made to solve the above problems, and its object is to provide a drive member control device that can suppress motor burnout even when control is terminated due to an abnormal process. [Means for solving the problem]

[0006] The driving member control device (2) that solves the above problem is a driving member control device (2) that controls a motor (M) that drives a driving member (1) and is equipped with a control unit (8) that limits the supply of power to the motor in response to an estimated motor temperature (A) reaching an operation limit threshold temperature (X1), and when the control unit determines that control was previously terminated due to an abnormal process at power-on, it sets the difference between the operation limit threshold temperature and the estimated motor temperature to be smaller than a maximum value.

[0007] According to this configuration, when the power is turned on, the difference between the operation limit threshold temperature and the estimated motor temperature is set to be smaller than the maximum value depending on whether control was previously terminated in an abnormal process. Therefore, for example, it is prevented that the estimated motor temperature at that time is set to a minimum motor temperature that is low and deviates from the actual motor temperature and is equivalent to the ambient temperature, and the motor continues to operate up to the normal operation limit threshold temperature. Therefore, even if control is terminated in an abnormal process, motor burnout is suppressed. [Brief description of the drawings]

[0008] [Figure 1] 1 is a schematic circuit diagram of a power window device according to an embodiment; [Diagram 2] FIG. 4 is a flow diagram illustrating an estimated motor temperature setting process by a control unit in one embodiment. [Diagram 3] 5 is a graph showing motor temperature versus time in one embodiment. [Figure 4] 5 is a graph showing motor temperature versus time in one embodiment. [Diagram 5]13 is a characteristic diagram of a motor temperature versus time in another example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment of a power window control device will be described with reference to FIGS. As shown in Fig. 1, a motor M in a power window device 2 serving as a drive member control device is drivingly connected to a window glass 1 serving as a drive member provided in a vehicle door D via a regulator (not shown) or the like. The motor M drives the window glass 1 to open and close.

[0010] (Configuration of power window device 2) The power window device 2 includes a rotation detection sensor 3 such as a Hall IC that detects the rotation speed of a motor M. The power window device 2 also includes a control unit 8 that controls the duty ratio of a drive circuit 7 based on a signal from the rotation detection sensor 3, a signal from an operation switch 4, a signal from a temperature sensor 5, the voltage of a battery 6, and the like, to supply a drive voltage to the motor M. The temperature sensor 5 in this embodiment is, for example, an outside air temperature sensor for detecting the outside air temperature to be displayed on a vehicle display. The control unit 8 includes a memory 9. The memory 9 is a non-volatile memory such as an NVRAM that stores various information including various preset threshold values ​​and is rewritable.

[0011] (Details of control unit 8) For example, in response to the operation of the operation switch 4, the control unit 8 supplies power to the motor M to drive the window glass 1 to open or close.

[0012] The control unit 8 also estimates an estimated motor temperature A. For example, the control unit 8 estimates the estimated motor temperature A based on the drive voltage supplied to the motor M, the number of rotations acquired from the rotation detection sensor 3, the elapsed time, and the ambient temperature Z acquired from the temperature sensor 5. For example, the control unit 8 gradually increases the estimated motor temperature A when the motor M is driven. The control unit 8 also gradually decreases the estimated motor temperature A according to the time that has elapsed since the driving of the motor M was stopped, and when the time that the motor M is not driven becomes long, the control unit 8 sets the estimated motor temperature A to the ambient temperature Z, which is the lowest motor temperature.

[0013] Furthermore, the control unit 8 limits the power supply to the motor M in response to the estimated motor temperature A reaching a preset operation limit threshold temperature X1. In this embodiment, the control unit 8 stops the power supply to the motor M when the estimated motor temperature A reaches the operation limit threshold temperature X1. Note that the operation limit threshold temperature X1 is set to a value smaller than the upper limit temperature X2 at which the motor M may burn out.

[0014] Furthermore, when the power is turned off to end control in a normal process, such as when the ignition switch is turned off, the control unit 8 stores in the memory 9 the estimated motor temperature A at that time. Then, when the power is turned on, such as when the ignition switch is turned on, the control unit 8 sets the estimated motor temperature A at that time according to the estimated motor temperature A read from the memory 9. When the power is turned on, the control unit 8 of this embodiment sets the difference between the operation limit threshold temperature X1 and the estimated motor temperature A to be smaller than the maximum value according to the determination that the control was previously terminated in an abnormal process. The maximum value of the difference between the operation limit threshold temperature X1 and the estimated motor temperature A is the difference from the operation limit threshold temperature X1 when the estimated motor temperature A becomes the minimum motor temperature, i.e., the ambient temperature Z. Therefore, in other words, when the power is turned on, the control unit 8 sets the difference between the operation limit threshold temperature X1 and the estimated motor temperature A to be smaller than the difference between the operation limit threshold temperature X1 and the minimum motor temperature according to the determination that the control was previously terminated in an abnormal process. Furthermore, the control unit 8 of this embodiment determines that control ended in an abnormal process last time based on the fact that the power supply was previously cut off, for example, by removing the battery 6 while the motor M was in operation, or based on a failure to store or read the estimated motor temperature A. Furthermore, the control unit 8 determines that the power supply was previously cut off while the motor M was in operation based on the fact that a flag that is set to "1" only while the motor M is in operation and set to "0" when the motor is normally stopped is already set to "1" when the power is turned on.

[0015] Specifically, the control unit 8 of this embodiment first stores in the memory 9 the estimated motor temperature A at the time when the estimated motor temperature A increases between when the power is turned on and when the power is turned off, as well as when the power is turned off. Specifically, the control unit 8 of this embodiment stores in the memory 9 the estimated motor temperature A at each time when the motor M finishes one operation.

[0016] Then, when the control unit 8 determines that control ended in an abnormal process the previous time based on the fact that the power was cut off while the motor M was operating when the power was turned on, it sets the stored estimated motor temperature A as the current estimated motor temperature A regardless of the elapsed time, etc. The estimated motor temperature A set at this time is the latest estimated motor temperature A including the estimated motor temperature A stored at the timing when the estimated motor temperature A rose between when the power was turned on and when the power was turned off.

[0017] In addition, when the control unit 8 determines that control was terminated in an abnormal process last time based on a failure to store or read the estimated motor temperature A when the power is turned on, the control unit 8 sets the estimated motor temperature A to the operation limit threshold temperature X1.

[0018] (Operation and Function of Power Window Device 2) Next, the specific operation and function of the above-mentioned power window device 2 will be described with reference to FIGS.

[0019] As shown in FIG. 2, the control unit 8 performs the estimated motor temperature setting process from step S1 onwards when the power is turned on by turning on the ignition switch, for example. In step S1, the control unit 8 performs a process of reading out the estimated motor temperature A stored in the memory 9, and determines whether or not the storage or reading of the estimated motor temperature A has failed, and if it determines that it has failed, the process proceeds to step S2. On the other hand, if the control unit 8 determines in step S1 that the storage or reading of the estimated motor temperature A has not failed, the process proceeds to step S3.

[0020] In step S2, the control unit 8 sets the estimated motor temperature A to the operation limit threshold temperature X1. For example, as shown in FIG. 3, when the control is ended in an abnormal process at timing T1, the estimated motor temperature A fails to be stored, and the estimated motor temperature A fails to be read out when the power is turned on at timing T2, the estimated motor temperature A is set to the operation limit threshold temperature X1. In FIG. 3, a white circle indicates that the estimated motor temperature A has been stored, and a black circle indicates that the estimated motor temperature A has been set. FIG. 3 also illustrates the actual motor temperature B, the estimated motor temperature C estimated by the control unit in the prior art, and the ambient temperature Z. FIG. 3 also illustrates the estimated motor temperature A when the power is turned off at timing T3 and the control is ended in a normal process, and when the power is turned on at timing T4 thereafter. FIG. 3 also illustrates the estimated motor temperature A when the motor M is repeatedly driven at timing T5 after timing T4, for example, to cause the window glass 1 to be fully opened and fully closed repeatedly.

[0021] In step S3, the control unit 8 determines whether the power was cut off the previous time while the motor M was operating, and if it is determined that the power was cut off, it proceeds to step S4, and if it is determined that the power was not cut off, it proceeds to step S5.

[0022] In step S4, the control unit 8 sets the stored estimated motor temperature A as the estimated motor temperature A as it is, regardless of the elapsed time, etc. For example, as shown in Fig. 4, if the power is cut off while motor M is operating and control is terminated due to an abnormal process at timing T6, when the power is turned on at timing T7, the last stored estimated motor temperature AZ is set as estimated motor temperature A. In Fig. 4, a white circle indicates that estimated motor temperature A has been stored, and a black circle indicates that estimated motor temperature A has been set. Fig. 4 also illustrates actual motor temperature B, estimated motor temperature C estimated by a control unit in the prior art, and ambient temperature Z.

[0023] In step S5, the control unit 8 corrects the stored estimated motor temperature A based on the elapsed time and sets it. For example, as shown in Fig. 4, if control ends in a normal process at timing T8, when the power is turned on at timing T9 after time has elapsed, a lower estimated motor temperature A is set by correcting the stored estimated motor temperature A by the elapsed time. Note that Fig. 4 illustrates a case in which the time from timing T8 to timing T9 is long, and the estimated motor temperature A set at timing T9 is the same as the ambient temperature Z. Fig. 4 also illustrates the estimated motor temperature A when, for example, at timing T10 after timing T9, the motor M is repeatedly driven to fully open and fully close the window glass 1.

[0024] Then, when the control unit 8 ends the above-mentioned estimated motor temperature setting process, it thereafter calculates and estimates the estimated motor temperature A every control period until, for example, the power is turned off. Then, the control unit 8 limits the power supply to the motor M in accordance with the estimated motor temperature A. When the estimated motor temperature A reaches the operation limit threshold temperature X1, the power supply to the motor M is stopped, and further heat generation is suppressed, thereby preventing burnout.

[0025] Next, the effects of the above embodiment will be described below. (1) When the power is turned on, depending on whether or not control was previously terminated in an abnormal process, the difference between the operation limit threshold temperature X1 and the estimated motor temperature A is set to be smaller than the maximum value. This prevents, for example, the motor M from continuing to operate up to the normal operation limit threshold temperature X1 while the estimated motor temperature A at that time is set to a minimum motor temperature that is low and deviates from the actual motor temperature B and is equivalent to the ambient temperature Z or the like. This prevents the motor M from burning out even when control is terminated in an abnormal process.

[0026] (2) Not only is estimated motor temperature A stored when the power is off, but estimated motor temperature A is also stored at the timing when estimated motor temperature A rises between when the power is on and when the power is off. In this way, it becomes possible to store estimated motor temperature A close to actual motor temperature B even when control is terminated due to an abnormal process, which was not possible by simply storing estimated motor temperature A when the power was off.

[0027] Then, for example, when the power is turned on, if it is determined that control ended in an abnormal process the previous time based on the fact that the power was cut off while the motor M was operating, the stored estimated motor temperature A is set as the current estimated motor temperature A. In this way, the estimated motor temperature A that is close to the actual motor temperature B and has not been corrected to be lower is used, thereby suppressing burnout of the motor M. For example, as shown in FIG. 4, since the estimated motor temperature A that is close to the actual motor temperature B and has not been corrected to be lower is used at timing T7, even if the motor M is driven at a later timing T11, the operation limit threshold temperature X1 is reached quickly, and burnout of the motor M is suppressed.

[0028] Also, for example, when the power is turned on and it is determined that control was terminated in an abnormal process last time based on failure to store or read the estimated motor temperature A, the estimated motor temperature A is set to the operation limit threshold temperature X1. That is, when the power is turned on and it is determined that control was terminated in an abnormal process last time based on failure to store or read the estimated motor temperature A, there is no basis for estimating the actual motor temperature B, so the estimated motor temperature A is set to the operation limit threshold temperature X1. Thus, burnout of the motor M is suppressed. For example, as shown in FIG. 3, since the estimated motor temperature A is set to the operation limit threshold temperature X1 at timing T2, even if the motor M is driven at a later timing T12, it quickly reaches the operation limit threshold temperature X1, and burnout of the motor M is suppressed.

[0029] This embodiment can be modified as follows: This embodiment and the following modifications can be combined with each other to the extent that there is no technical contradiction. In the above embodiment, the control unit 8 sets the estimated motor temperature A in response to determining that control ended in an abnormal process the previous time when the power is turned on, but this is not limited thereto, and the operation limit threshold temperature X1 may be temporarily changed. That is, when the control unit 8 determines that control ended in an abnormal process the previous time when the power is turned on, the operation limit threshold temperature may be set to an abnormal operation limit threshold temperature X3 that is lower than the normal operation limit threshold temperature X1. In this case, the control unit 8 does not need to store the estimated motor temperature A at the timing when the estimated motor temperature A increases between when the power is turned on and when the power is turned off.

[0030] For example, as shown in FIG. 5, if control is terminated in an abnormal process at timing T13, an abnormal operation limit threshold temperature X3 that is lower than the normal operation limit threshold temperature X1 is set when the power is turned on at timing T14. At timing T14, an estimated motor temperature A is set that is the same as the ambient temperature Z stored at timing T3 because control was previously terminated in an abnormal process. However, since an abnormal operation limit threshold temperature X3 that is lower than the normal operation limit threshold temperature X1 is set when the power is turned on at timing T14, even if the motor M is driven at a later timing T15, the motor M will reach the operation limit threshold temperature X3 quickly. This prevents the motor M from burning out.

[0031] In the above embodiment, the control unit 8 sets a different estimated motor temperature A depending on whether the power was previously cut off while the motor M was operating or whether the storage or reading of the estimated motor temperature A failed, but this is not limited to the above.

[0032] For example, when the control unit 8 determines that control was terminated in an abnormal process last time when the power is turned on, it may set the estimated motor temperature A to the operation limit threshold temperature X1 even if the power was cut off last time while the motor M was operating.

[0033] Also, for example, if the power was cut off while the motor M was operating the previous time, the control unit 8 may set the stored estimated motor temperature A as the current estimated motor temperature A, and if the storage or reading of the estimated motor temperature A fails, the control unit 8 may prohibit power supply to the motor M.

[0034] In the above embodiment, the operation limit threshold temperature X1 is a temperature at which the power supply to the motor M is forcibly stopped when the estimated motor temperature A is reached. However, this is not limited to this, and for example, the operation limit threshold temperature X1 may be a temperature at which the operation of a new motor M is prohibited when the estimated motor temperature A is reached.

[0035] In the above embodiment, the control unit 8 determines that control was terminated in an abnormal process last time based on the fact that the power was cut off while the motor M was operating or the storage or reading of the estimated motor temperature A failed, but the determination may be made based on other conditions.

[0036] In the above embodiment, the control unit 8 stores the estimated motor temperature A in the memory 9 each time the motor M finishes one operation, but the estimated motor temperature A may be stored at other times when the estimated motor temperature A rises between when the power is turned on and when the power is turned off. For example, the control unit 8 may store the estimated motor temperature A when a certain time (e.g., 2 seconds, 3 seconds, etc.) has elapsed during the operation of the motor M, in addition to when the motor M finishes one operation.

[0037] In the above embodiment, the control unit 8 estimates the estimated motor temperature A based on the drive voltage, the rotation speed, the elapsed time, and the ambient temperature Z, but this is not limiting and the estimated motor temperature A may be estimated based on other information. For example, the power window device 2 may be provided with an ammeter that detects the drive current of the motor M, and the estimated motor temperature A may be estimated based on the current value obtained from the ammeter.

[0038] In the above embodiment, the driving member is the power window device 2 in which the window glass 1 is used. However, the present invention is not limited to this, and may be embodied in another driving member control device that drives another driving member. [Explanation of symbols]

[0039] 1...window glass (driving member), 2...power window device (driving member control device), 8...control unit, A...estimated motor temperature, M...motor, X1...(normal) operation limit threshold temperature, X3...abnormal operation limit threshold temperature.

Claims

1. A drive member control device (2) including a control unit (8) that controls a motor (M) that drives a drive member (1) and limits power supply to the motor in response to an estimated motor temperature (A) reaching an operation limit threshold temperature (X1), the control unit is configured to set a difference between the operation limit threshold temperature and the estimated motor temperature to be smaller than a maximum value in response to determining that control was previously terminated due to an abnormal process when the power is turned on; Furthermore, the control unit not only stores the estimated motor temperature when the power is off, but also stores the estimated motor temperature at a timing when the estimated motor temperature increases between when the power is on and when the power is off, When the power is turned on, if it is determined that control was terminated in an abnormal process the previous time based on the fact that the power was turned off while the motor was in operation, the estimated motor temperature stored at the timing when the estimated motor temperature rose between the time when the power was turned on and the time when the power was turned off is set as the current estimated motor temperature. A drive member control device that, when powered on, determines that control was terminated in an abnormal process the previous time based on a failure to store or read the estimated motor temperature, sets the estimated motor temperature to the operation limit threshold temperature.

2. A driving member control device (2) having a control unit (8) that controls a motor (M) that drives a driving member (1) and limits power supply to the motor in response to an estimated motor temperature (A) reaching an operation limit threshold temperature (X1), the control unit is configured to set a difference between the operation limit threshold temperature and the estimated motor temperature to be smaller than a maximum value in response to determining that control was previously terminated due to an abnormal process when the power is turned on; Furthermore, the control unit not only stores the estimated motor temperature when the power is off, but also stores the estimated motor temperature at a timing when the estimated motor temperature increases between when the power is on and when the power is off, When the power is turned on and it is determined that control was terminated due to an abnormal process the previous time, the drive member control device sets the estimated motor temperature stored at the time when the estimated motor temperature rose between when the power was turned on and when the power was turned off as the current estimated motor temperature.

3. A driving member control device (2) having a control unit (8) that controls a motor (M) that drives a driving member (1) and limits power supply to the motor in response to an estimated motor temperature (A) reaching an operation limit threshold temperature (X1), the control unit is configured to set a difference between the operation limit threshold temperature and the estimated motor temperature to be smaller than a maximum value in response to determining that control was previously terminated due to an abnormal process when the power is turned on; Furthermore, the control unit not only stores the estimated motor temperature when the power is off, but also stores the estimated motor temperature at a timing when the estimated motor temperature increases between when the power is on and when the power is off, When the power is turned on and it is determined that control was terminated in an abnormal process the previous time based on the fact that the power was cut off while the motor was operating, the drive member control device sets the estimated motor temperature stored at the time when the estimated motor temperature rose between when the power was turned on and when the power was turned off as the current estimated motor temperature.

Citation Information

Patent Citations

  • Electronic control device

    JP2015024754A

  • Motor control device and motor

    JP2019106767A

  • Driving device and control method of the driving device

    JP2021158788A

  • Electric power steering apparatus

    WO2008153162A1