JP4245982B2 - Mirror control device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a mirror control device that controls the operation of an electric remote-controlled side mirror attached to a vehicle such as an automobile.
[0002]
[Prior art]
[Patent Document 1]
JP 2001-130326 A
[0003]
Conventionally, in a side mirror attached to the door of an automobile, the mirror automatically faces downward when the automobile is retracted, so that the driver can check the field of view near the rear wheel through the mirror, and the mirror is usually There is a reverse interlocking mirror that automatically returns to the position. In the conventional reverse interlocking mirror, the current flowing through the timer, the position sensor, the limit switch, and the drive motor in order to detect that the mirror has been moved to the predetermined downward tilt position and returned to the normal position. It was controlled using a pulse or the like.
[0004]
[Problems to be solved by the invention]
However, when the timer is used, there is a problem that the mirror cannot be accurately returned to the normal position due to a difference in motor speed between the downward tilt and the return, a difference in voltage or temperature, and the like. In addition, when a position sensor or limit switch is used, the number of parts increases, resulting in an increase in cost, and there is a problem that the size of the door mirror is increased by storing these parts inside. Furthermore, when a current pulse flowing through the motor is used, even if the mirror reaches the downward tilt limit position, the motor will run idle due to the clutch, so that a current pulse will continue to be generated. There is a problem that it is not possible to determine that it has reached.
[0005]
On the other hand, instead of using the timer, the position sensor, and the limit switch, in Patent Document 1, a pulse is generated from the current flowing through the motor, and the tilt angle of the mirror is controlled based on the number of pulses. A mirror control device has been proposed. However, in this mirror control device, it is necessary to preset the number of pulses required for the mirror to reach a predetermined downward tilt position from the normal position for each vehicle type.
[0006]
Therefore, an object of the present invention is to provide a mirror control device that does not require initial setting and can be mounted on any vehicle without tuning.
[0007]
[Means for Solving the Problems]
  To achieve the above object, the present invention is a mirror control device having a motor that operates a mirror attached to a vehicle by a predetermined switch operation between a normal position and a predetermined downward inclined position,
  Current detecting means for detecting a lock current flowing in the motor, brush noise detecting means for detecting brush noise generated by the operation of the motor, and noise for counting and storing the brush noise detected by the brush noise detecting means And when the mirror is operated from the normal position to the downward inclined position.BeforeThe number of occurrences of the brush noise is stored by the noise storage means, and it is determined by the lock current of the motor detected by the current detection means that the mirror has reached the downward tilt position, and the mirror is tilted downward When returning from the position to the normal position, the mirror is operated to the normal position by reversing the motor based on the number of brush noises stored in the noise storage means.The
[0008]
According to this configuration, it is possible to determine that the mirror has reached the predetermined downward tilt position by detecting the lock current of the motor. Therefore, the motor generated before reaching the predetermined downward tilt position from the normal position. It is not necessary to initialize the number of current pulses for each vehicle type in advance, and it can be installed in any vehicle without tuning, and the development man-hours can be greatly reduced.
Further, there is no need for switches for detecting that the mirror has reached a predetermined downward tilt position, and the cost can be reduced.
Further, there is no operation error due to a difference in motor speed or voltage, and the mirror can be reliably returned to the normal position with a simple configuration.
Further, even when the mirror does not operate due to icing or the like, an abnormality can be reliably detected by the lock current of the motor, and damage to the motor can be reduced.
[0009]
  The present inventionThe mirror controller ofOperating time memory for storing the operating time of the motorA step is provided toThe operation time of the motor during normal operation is stored by the operation time storage means, and if the noise storage means cannot normally count the brush noise due to external noise or the like, the motor is stored in the operation time storage means The motor is operated only during the normal operation time of the motor.
[0010]
According to this configuration, even when brush noise cannot be counted, a backup that enables the mirror to return to the normal position on the basis of the operation time of the motor during normal operation becomes possible.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the accompanying drawings.
FIG. 1 is a block diagram of a mirror control device 10 according to an embodiment of the present invention. The mirror control device 10 includes motors 12R and 12L for operating the mirror main bodies (hereinafter simply referred to as “mirrors”) of left and right door mirrors (not shown), which are side mirrors, upward or downward, respectively. . The motors 12R and 12L are respectively gear-coupled to the left and right mirrors via clutches. In addition, illustration of the motor for operating each mirror in the left-right direction is omitted.
[0012]
The motors 12R and 12L are electrically connected to a motor drive circuit 14. The motor drive circuit 14 is electrically connected to a power source 16 that is a battery and is supplied with power. The power supply 16 is electrically connected to the manual switch circuit 18. The manual switch circuit 18 is electrically connected to each of the motors 12R and 12L, and is for the driver to manually operate each mirror upward or downward.
[0013]
The power supply 16 is electrically connected to a control unit (noise storage means and operation time storage means) 22 via a voltage adjustment circuit 20. The voltage adjustment circuit 20 is for adjusting the voltage (for example, 12V) supplied from the power supply 16 to the drive voltage (for example, 5V) of the IC constituting the control unit 22. The control unit 22 is electrically connected to the motor drive circuit 14 and transmits a signal for operating or stopping each of the motors 12R and 12L.
[0014]
The motor drive circuit 14 is electrically grounded via the detection resistor 24. A lock current detection circuit (current detection means) 26 and a brush noise detection circuit (brush noise detection means) 28 are electrically connected between the motor drive circuit 14 and the detection resistor 24, respectively. The lock current detection circuit 26 and the brush noise detection circuit 28 are electrically connected to the control unit 22, respectively.
[0015]
The lock current detection circuit 26 introduces a motor current that flows when the motors 12R and 12L are driven from the motor drive circuit 14, and calculates a lock current when the motors 12R and 12L are stopped (locked) due to torque over. It is for detection.
[0016]
The brush noise detection circuit 28 is configured by connecting an amplifier circuit 30, a filter circuit 32, and a waveform shaping circuit 34 in series, and a motor current that flows when the motors 12R and 12L are driven is introduced from the motor drive circuit 14. In order to detect brush noise. Here, the brush noise generated in the motor current is in contact or non-contact with the power supply brush in which the rotating commutator for supplying power to the electromagnet coil of the rotor is fixedly arranged inside the motor having a known structure. This is a periodic current fluctuation generated by repeating the state.
[0017]
A system switch 36 and a reverse switch 38 are electrically connected to the controller 22. The system switch 36 is a switch that allows the driver to manually switch whether or not to operate the mirror control device 10. The reverse switch 38 is a switch that switches from off to on when the AT shift lever of the automobile is operated to the reverse range.
[0018]
FIG. 2A shows the waveform of the motor current introduced into the lock current detection circuit 26 and the brush noise detection circuit 28 in the mirror control device 10 having the above configuration. As shown in FIG. 2A, when the motor is turned on, an inrush current that protrudes and flows flows, but after that, although a small brush noise is generated, a substantially constant steady current flows. . Then, after the motor is driven and the mirror is actuated to reach a downward inclination limit position where the mirror cannot be inclined further downward, the motor gradually decelerates and stops. At this time, the motor current gradually increases and becomes a lock current exceeding a threshold value higher than the steady current by a predetermined value by stopping the motor. The lock current is detected by the lock current detection circuit 26, and the detected lock current is input to the control unit 22 and digitized by A / D conversion. The numerical value of the lock current can be stored by the control unit 22.
[0019]
In the state where the lock current flows to the motor, in the mirror control device 10 of the present embodiment, each motor 12R, 12L is connected to the mirror via the clutch, so that the driving torque of the motor exceeds the predetermined torque of the clutch. Sometimes the clutch slips and the motor spins slightly and then stops again. During this idling, the lock current once decreases, but the lock current starts to increase again when the motor is stopped again. As described above, when the motor repeats idling and stopping, the lock current draws a considerable number of peaks until the power supply to the motor is stopped.
[0020]
On the other hand, in the brush noise detection circuit 28, the motor current including the brush noise is first amplified by the amplification circuit 30 with respect to the steady current of the motor current, and then the motor current is filtered by the filter circuit 32 as shown in FIG. The waveform component of the brush noise excluding the direct current component is taken out, and then the waveform shaping circuit 34 shapes the brush noise into a rectangular pulse wave as shown in FIG. Will be counted. In the rectangular pulse wave shown in FIG. 2 (c), since the motor is accelerating, the generation interval of each rectangular pulse is gradually shortened. However, when the motor rotates at a constant speed, the interval between the rectangular pulses is as follows. Are equally spaced.
[0021]
Next, control by the control unit 22 of the mirror control device 10 will be described with reference to FIGS.
FIG. 3 shows a main routine of control by the control unit 22. In this process, first, in step S1, the control unit 22 is initialized, and then in step S2, it is determined whether 10 msec has elapsed. If it is determined that 10 msec has elapsed, the process proceeds to the next process. Thereby, the processing after step S3 is executed every 10 msec. In the processes after step S3, the return process returns to the previous step by step S8 “return return”.
[0022]
Next, in step S3, the switch state is read. At this time, the on / off states of the system switch 36 and the reverse switch 38 are acquired. In step S4, it is determined whether the reverse switch 38 is on and the system switch 36 is on. At this time, when it is determined that the reverse switch 38 is ON and the system switch is ON (that is, the AT shift lever of the automobile is operated to the reverse range, and the mirror control device 10 is operable. In the state), the reverse mode is executed in step S5. Here, the reverse mode is a process of operating the mirror from the normal position to the downward tilt limit position, as will be described later.
[0023]
On the other hand, when it is not determined in step S4 that the reverse switch 38 is on and the system switch 36 is on, it is determined in step S6 whether the reverse switch is off and the inversion flag is 1. Here, the reverse flag is a flag that is set to 1 at the end of the reverse mode processing executed in step S5 (that is, after the mirror is operated from the normal position to the downward tilt limit position).
[0024]
When it is determined in step S6 that the reverse switch 38 is OFF and the reverse flag is 1 (that is, the AT shift lever is operated from the reverse range to another position after the mirror is operated to the downward tilt limit position) In step S7, the inversion mode is executed. Here, the reverse mode is a process of returning the mirror from the downward tilt limit position to the normal position, as will be described later. On the other hand, in step S6, when it is not determined that the reverse switch 38 is off and the reverse flag is 1, the process ends.
[0025]
FIG. 4 is a flowchart of the interrupt processing step S35 that is executed each time brush noise is input from the brush noise detection circuit 28 to the control unit 22. In the interrupt process in step S35, first, in step S36, once an interrupt occurs, the interrupt is prohibited for 0.6 msec, thereby removing noise in software. Next, in step S37, the number of pulse counts is increased by 1, and brush noise is counted. Then, the process returns to the interrupt position. In this way, the number of occurrences of brush noise is stored and saved.
[0026]
Next, the reverse mode in step S5 will be described with reference to FIG. In the reverse mode, first, the motors 12R and 12L are operated in step S21. As a result, the left and right mirrors start tilting from the normal position toward the downward tilt limit position. Subsequently, in step S22, it is determined whether or not the motor operating time is 0. When it is determined that the motor operating time is 0, measurement of the motor operating time is started in step S23, and when the motor operating time is not determined to be 0. Since the motor operating time is being measured, the process proceeds to step S24. The interrupt processing S35 for brush noise count described above can be interrupted after the start of the motor operation time measurement in step S23.
[0027]
Next, in step S24, it is determined whether the motor operating time is longer than 300 msec. This prevents the lock current detection circuit 26 from detecting the lock current at the start of driving the motor, thereby preventing the inrush current (see FIG. 2) from being regarded as the lock current. If it is determined in step S24 that the motor operating time is shorter than 300 msec, the process returns to step S8. On the other hand, if it is determined that the motor operating time is longer than 300 msec, a brush noise pulse abnormality determination is performed in step S25. Do. Here, the pulse input interval of the brush noise is normally about 1 to 2 msec. Therefore, if there is no pulse within 10 msec from the previous pulse input, it is determined that the pulse is in an abnormal state where the brush noise cannot be counted due to external noise or the like. To do.
[0028]
If it is determined in step S25 that the pulse is abnormal, the down pulse impossible flag RFD is set to 1 in step S26. On the other hand, if it is not determined that the pulse is abnormal, lock current determination is performed in step S27. Here, when the motor current detected by the lock current detection circuit 26 exceeds the threshold of (1) steady current + predetermined value (for example, 0.3 A) with reference to the steady current, or (2) FIG. When the routine shown in FIG. 5 is repeatedly executed a predetermined number of times (for example, 6 times) and continuously increased from the previous motor current, the lock current is determined when any of the conditions is satisfied. In the condition (2), “the motor current continuously increases a predetermined number of times” is to prevent erroneous determination due to noise.
[0029]
If it is determined in step S27 that the current is not a lock current, the process returns to step S8. On the other hand, if it is determined that the current is a lock current, it can be determined that the motor has locked because the mirror has reached the downward tilt limit position. In S28, the operation of the motors 12R and 12L is stopped, and the pulse count (that is, the number of occurrences of brush noise) counted by the interrupt process in FIG. 4 is stored as a PD value.
[0030]
In step S29, the PD value is corrected. This correction is performed by adding to the PD value a pulse number (for example, 10 pulses) corresponding to the amount of play of the gear connecting the motor and the mirror, but it may be corrected depending on the previous mirror operation direction stored. May or may not be necessary.
[0031]
The reason for performing such correction is as follows. As shown in FIG. 7A, when the mirror has been operated from the upward inclined position to the normal position in the previous manual mirror operation, the mirror is moved from the normal position by executing the reverse mode in step S5. The number of pulse counts of the motor generated during operation to the downward tilt limit position (illustrated as “downward”) does not include the number of pulses corresponding to the gear play. This is because the previous mirror operation direction and the current mirror operation direction are the same, and there is no gear rattling when the mirror starts to operate from the normal position toward the downward tilt limit position. On the other hand, when returning the mirror from the downward tilt limit position to the normal position in the reverse mode of step S7 described later, the mirror operating direction is opposite to the mirror operating direction in the previous execution of step S5. Gear backlash will occur. For this reason, the number of pulse counts of the motor necessary for accurately returning the mirror from the downward tilt limit position to the normal position is set to the number of pulses corresponding to the rattling of the gear in step S5. It must be added to the number of pulses counted by execution. Therefore, in the PD value correction in step S29, the number of pulses corresponding to the rattling of the gear is added to the PD value that is actually counted until the mirror is moved from the normal position to the downward tilt limit position. The correction is carried out.
[0032]
In step S29, PD value correction may not be necessary. As shown in FIG. 7B, when the mirror has been operated from the downward inclined position to the normal position in the previous manual mirror operation, the mirror is moved by executing the reverse mode in step S5. The number of pulse counts of the motor generated during operation from the normal position to the downward tilt limit position includes the number of pulses corresponding to the gear play. This is because the previous mirror operating direction and the current mirror operating direction are opposite, and there is a backlash of the gear when the mirror starts to operate from the normal position toward the downward tilt limit position. Therefore, since the number of pulses actually counted by the execution of step S5 already includes the number of pulses corresponding to the rattling of the gear, correction of the PD value is not necessary in this case.
[0033]
Following step S29, the motor operating time is stored as a normal operating time in step S30. In step S31, the motor operation time and the pulse count are reset, and the reverse flag is set to 1. Then, the process returns to step S8. Thereby, the process of the reverse mode of step S5 is complete | finished, and a mirror act | operates to a downward inclination limit position.
[0034]
Next, the inversion mode in step S7 will be described with reference to FIG. The reverse mode is a process of rotating the motor in reverse to return the mirror from the downward tilt limit position to the normal position. However, steps S40 to S45 are the same as steps S21 to S26 in the reverse mode, and thus redundant description will be given. Omitted. However, in step S45, the setting object is different from that in step S26 in the reverse mode, and the up-time pulse disable flag RFU is set to 1.
[0035]
In subsequent step S46, when both the down pulse disable flag RFD and the up pulse disable flag RFU are 0 (that is, when the pulse input is normal in both the downward operation and upward operation of the mirror), the mirror upward The pulse count during operation is compared with the PD value stored during mirror downward operation. At this time, if it is determined that the pulse count is at least equal to the PD value, it can be determined that the mirror has returned to the normal position. Therefore, in step S47, the measured motor operating time is stored as a normal operating time. Thereafter, the motor is stopped in step S49. In the following step S50, the motor operation time and pulse count are reset and the reverse flag is set to 0, and then the process returns to step S8.
[0036]
On the other hand, if it is not determined in step S46 that both the down pulse disable flag RFD and the up pulse disable flag RFU are 0, the down pulse disable flag RFD or the up pulse disable flag RFU is 1 in step S48 ( That is, it is determined that the pulse input during the downward operation or upward operation of the mirror is abnormal). At this time, the measured motor operation time is compared with the stored normal operation time, the motor is operated in reverse until the motor operation time at least matches the normal operation time, and then the motor is stopped in step S49. To do. Similarly, in step S50, the motor operation time and the pulse count are reset and the reverse flag is set to 0, and then the process returns to step S8.
[0037]
As a result, the reverse mode processing is completed, and the mirror is moved from the downward tilt limit position by reversely operating the motor based on the pulse count number during the downward operation when the pulse is normal or based on the normal operation time when the pulse is abnormal. It is possible to accurately return to the normal position.
[0038]
As described above, according to the mirror control device 10 of the present embodiment, it is possible to determine that the mirror has reached the downward tilt limit position by detecting the lock current of the motor. It is not necessary to preset the number of motor current pulses generated before reaching the tilt limit position for each vehicle type, and it can be mounted on any vehicle without tuning, and the development man-hours can be greatly reduced.
[0039]
Further, there is no need for switches for detecting that the mirror has reached the downward tilt limit position, and the cost can be reduced.
[0040]
Further, there is no operation error due to a difference in motor speed or voltage, and the mirror can be reliably returned to the normal position with a simple configuration.
[0041]
Further, even when the mirror does not operate due to icing or the like, an abnormality can be reliably detected by the lock current of the motor, and damage to the motor can be reduced.
[0042]
Furthermore, even when brush noise cannot be counted, a backup that enables the mirror to return to the normal position on the basis of the operation time of the motor during normal operation becomes possible. The motor operating time during normal operation need not be preset for each vehicle type, and the motor operating time can be automatically set according to the vehicle type.
[0043]
By the way, the lock current detection circuit 26 of the mirror control device 10 may have a variable current amplification factor by adopting a circuit configuration including a transistor 26a and an operational amplifier 26b as shown in FIG. When the value of the steady current flowing through the motors 12R and 12L decreases due to the voltage drop of the power supply 16, the lock current also decreases, and the influence of noise from the outside increases, making it difficult to determine motor lock. Therefore, when the value of the current input to the lock current input unit 23 becomes smaller than a predetermined current value when the motor is in a steady state, the control unit 22 transmits to the transistor 26a to increase the amplification factor of the operational amplifier 26b. The current value can be increased.
[0044]
In addition, the specific numerical values of the time and the number of times used for the control of the mirror control device 10 of the above-described embodiment are merely examples, and can naturally be changed depending on the characteristics of the motor used.
[0045]
【The invention's effect】
As is apparent from the above description, according to the mirror control device of the present invention, it is possible to determine that the mirror has reached the predetermined downward tilt position by detecting the lock current of the motor. There is no need to preset the number of motor current pulses generated before reaching a predetermined downward tilt position for each vehicle type, and it can be installed in any vehicle without tuning, greatly reducing development man-hours. it can.
[0046]
Further, there is no need for switches for detecting that the mirror has reached a predetermined downward tilt position, and the cost can be reduced.
[0047]
Further, there is no operation error due to a difference in motor speed or voltage, and the mirror can be reliably returned to the normal position with a simple configuration.
[0048]
Further, even when the mirror does not operate due to icing or the like, an abnormality can be reliably detected by the lock current of the motor, and damage to the motor can be reduced.
[0049]
Furthermore, in the mirror control device of the present invention, an operation time storage means for storing the operation time of the motor is provided, and the operation time of the motor during normal operation is stored by the operation time storage means, so that noise from the outside etc. If the noise storage means cannot normally count the brush noise, the brush noise is counted when the motor is operated only during the normal operation time stored in the operation time storage means. Even if this is not possible, it is possible to back up the mirror so that the mirror can be returned to the normal position based on the motor operating time during normal operation.
[Brief description of the drawings]
FIG. 1 is a block diagram of a mirror control device.
2A is a motor current waveform detected by a lock current detection circuit, FIG. 2B is a brush noise waveform extracted and amplified by a brush noise detection circuit, and FIG. 2C is a brush noise detection circuit. The figure which respectively shows the rectangular pulse waveform of the brush noise which was made.
FIG. 3 is a flowchart showing a main routine of the mirror control device.
FIG. 4 is a flowchart showing interrupt processing for pulse counting.
FIG. 5 is a flowchart showing a reverse mode for operating the mirror downward.
FIG. 6 is a flowchart showing an inversion mode for operating the mirror upward.
FIG. 7 is a diagram for explaining PD value correction.
FIG. 8 is a diagram showing a part of a lock current detection circuit.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Mirror control apparatus, 12R, 12L ... Motor, 14 ... Motor drive circuit, 18 ... Manual switch circuit, 20 ... Voltage adjustment circuit, 22 ... Control part (noise storage means and operation time storage means), 26 ... Lock current detection Circuit (current detection means), 28 ... brush noise detection circuit (brush noise detection means), 36 ... system switch, 38 ... reverse switch.

Claims (1)

A mirror control device having a motor for operating a mirror attached to a vehicle by a predetermined switch operation between a normal position and a predetermined downward inclined position,
  Current detecting means for detecting a lock current flowing in the motor, brush noise detecting means for detecting brush noise generated by the operation of the motor, and noise for counting and storing the brush noise detected by the brush noise detecting means Storage means and operation time storage means for storing the operation time of the motor are provided, and when the mirror is operated from a normal position to the downward tilt position, the number of occurrences of the brush noise is stored by the noise storage means. At the same time, it is determined that the mirror has reached the downward tilt position based on the motor lock current detected by the current detection means, and the noise storage means is used when returning the mirror from the downward tilt position to the normal position. Based on the number of stored brush noises, the motor is reversed and the mirror is normally If the operation time storage means stores the operation time of the motor during normal operation, and the noise storage means cannot normally count brush noise due to external noise or the like, the motor Is operated only for the motor operation time during normal operation stored in the operation time storage means.

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