JP2004274804A - Method and apparatus for controlling motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent wiper arm position control from being deviated due to the unevenness of a sensor position. <P>SOLUTION: A sensor magnet is provided at an output shaft at which a rotating angle is restricted between a lower limit position and an upper limit position, and Hall ICs are disposed oppositely. A multipolarly magnetized magnet is provided even at the rotating shaft of a motor, and the Hall ICs are disposed oppositely. The output shaft is rotated from the lower limit position toward the upper limit position (S12, S13). When a reference signal is obtained (S14), the pulse count value of the Hall IC until the reference signal is obtained is stored as a first reference value (S15). Thereafter, the output shaft is rotated to the upper limit position (S16), and rotated from the upper limit position toward the lower limit position (S17). When the reference signal is obtained (S18), the pulse counted value of the Hall IC until the reference signal is obtained is stored as a second reference value (S19). When the reference signal is obtained at the motor operating time, the pulse counted value is reset by using the first or second reference value in response to the rotative direction. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a control method and a control device for an electric motor, and more particularly, to an initial setting of a motor of an automobile wiper device.
[0002]
[Prior art]
The installation space for the wiper system has been reduced year by year due to the enlargement of the engine and the master power of the brake. For this reason, in recent years, a method has been put to practical use in which the operating area of the link is reduced to less than half by rotating the motor forward and backward within 180 °, and the wiper can be driven in a small space. In this motor forward / reverse rotation method, since the reversing operation can be performed at an arbitrary position within the wiping angle, the storage position can be set further below the lower reversal position after setting the lower reversal position. Therefore, many luxury cars adopt this method and incorporate a wiper storage function.
[0003]
In order to perform forward / reverse rotation of the motor in the wiper system, it is necessary to detect the position of the wiper arm in order to perform forward / reverse rotation of the motor at an arbitrary position. The detection of the wiper arm position is performed by adding or subtracting the number of pulses generated in conjunction with the rotation of the motor. A multipolar magnetized magnet is attached to the motor rotation shaft, and a sensor such as a Hall IC that captures a change in magnetic pole accompanying the rotation and outputs a pulse signal is arranged to face the magnet. The pulse count is reset at one point (origin position) serving as a reference for the rotational position of the motor unit output shaft, thereby preventing the occurrence of a pulse shift.
[0004]
FIG. 10 is an explanatory diagram showing a configuration for obtaining a pulse reset signal. A sensor magnet 51 as shown in FIG. 10 is attached to the output shaft of the motor unit. A sensor 52 such as a Hall IC is arranged for the sensor magnet 51 so that a reference signal is output when the magnetic pole approaches a predetermined reference position. When the reset signal is output from the sensor 52, the motor rotation angle from the reference position is calculated by adding and subtracting pulses from that point.
[0005]
If the motor rotation angle is known, the current wiper arm position can be detected in consideration of the reduction ratio, the link ratio, and the like. Also, the wiper arm moving speed can be detected from the cycle of the motor rotation pulse. In actual control, the wiper arm position and the arm speed are recognized by the pulse count and the pulse cycle. The motor control system includes a forward / reverse rotation circuit such as an H-bridge circuit using an FET, and control means such as a CPU for controlling the speed and rotation angle of the motor. The motor is controlled based on the position and speed of the wiper arm. Is controlled.
[0006]
[Patent Document 1] Japanese Utility Model Registration No. 25618686
[Patent Document 2] Japanese Patent Application Laid-Open No. 14-262515
[0007]
[Problems to be solved by the invention]
However, when looking at the entire wiper system, there are various dimensional fluctuation factors such as variations in dimensions and assembly of system components, variations in characteristics of the sensor itself, and variations in magnetization of the sensor magnet 51. For this reason, the conventional motor control method has a problem that the reset position by the sensor 52 is slightly shifted for each product, and it is difficult to maintain the reversal position accuracy of the wiper arm commonly for the entire product.
[0008]
11A and 11B are explanatory diagrams showing the relationship between the pulse count and the wiper position. FIG. 11A shows a case where the sensor 52 is at a regular position, and FIG. 11B shows a case where the sensor 52 is at a position shifted by an error. Is shown. In this system, when a reset signal from the sensor 52 is input, the pulse count value is reset to the reference value S. As shown in FIG. 11A, if the sensor 52 is at the normal position, the pulse count value is reset to the reference value S at the correct position. Therefore, if the pulse count value is a normal value, the value is integrated linearly without a break as shown in FIG. If there is an error in the pulse count value, the pulse signal is reset to the correct pulse count value (reference value S) at that position by the reset signal of the sensor 52 at the correct position, and the pulse count value is corrected.
[0009]
However, when the sensor 52 is not at the normal position, the pulse count value is reset to the reference value S at an incorrect position. That is, as shown in FIG. 11B, the misplaced mounting position is misunderstood as the normal position, and the pulse count value is reset at this error position. For this reason, the pulse count value is thereafter accumulated in a form including an error, and the wiper reversal position is shifted by the error.
[0010]
Generally, the operating range of the wiper arm is mechanically limited, and if the wiper reversal position is shifted, the wiper arm may overrun beyond this range. In this case, the mechanical operation restricting means acts to stop the wiper arm, but the motor may be locked accordingly. Further, such a situation that an abnormal sound is generated when the wiper arm is stopped or the wiper arm is stopped by impact is not preferable in terms of operation feeling and durability of the apparatus, and improvement thereof has been demanded.
[0011]
An object of the present invention is to prevent displacement of wiper arm position control due to variation in sensor position.
[0012]
[Means for Solving the Problems]
According to the motor control method of the present invention, the rotation of the rotation shaft is transmitted at a reduced speed via a motor body having a rotation shaft and a speed reduction mechanism, and the rotation angle is regulated between a first limit position and a second limit position. An output shaft, a first sensor that is provided to face a detected member that is interlocked with the output shaft, and that outputs a reference signal when a predetermined portion of the detected member faces the output shaft; and a first sensor that is provided to the rotating shaft. A second sensor that is provided to face the member to be detected and that outputs a pulse signal in accordance with the rotation of the rotating shaft, wherein the output shaft is moved from the first limit position The first position of the first sensor is rotated toward the second limit position based on a pulse count value of the pulse signal output by the second sensor from the first limit position to a position where the reference signal is obtained. Create the information and When at obtain said reference signal, and correcting the pulse count value of the pulse signal by using the first position information.
[0013]
In the present invention, since the first position information of the first sensor is created in advance and the pulse count value is corrected based on the value, the pulse count value is corrected by reflecting the actual sensor position. For this reason, even if the mounting position of the first sensor is shifted, the pulse count does not shift. Therefore, for example, when the motor is applied to a wiper device, the reversal position of the blade does not shift for each product, and the reversal position accuracy can be maintained in common for the entire product. In addition, overrun of the blade can be prevented, and stoppage of the wiper arm due to mechanical abutment can be avoided. Therefore, it is possible to prevent the motor from being locked, generating abnormal noise, and stopping the wiper arm from being impacted, thereby improving the operational feeling and the durability of the apparatus.
[0014]
In the motor control method, the output shaft is rotated from the second limit position toward the first limit position, and the second sensor outputs the position from the second limit position to a position where the reference signal is obtained. The second position information of the first sensor may be created based on a pulse count value of a pulse signal.
[0015]
Further, in the motor control method, when the output shaft rotates from the first limit position toward the second limit position, the pulse count value of the pulse signal is corrected using the first position information. When the output shaft rotates from the second limit position toward the first limit position, the pulse count value of the pulse signal may be corrected using the second position information. Thereby, even if a difference occurs between the first position information and the second position information due to the characteristics of the first sensor, the pulse count value is corrected using appropriate position information depending on the passing direction of the detected member, Pulse shift due to sensor characteristics can be prevented.
[0016]
Further, in the motor control method, a magnet may be used as the detected member, and a Hall IC may be used as the first and second sensors.
[0017]
On the other hand, the motor control device of the present invention includes a motor body having a rotating shaft, and the rotation of the rotating shaft is transmitted at a reduced speed via a speed reduction mechanism, and a rotation angle between a first limit position and a second limit position. A first sensor for providing a reference signal when a predetermined portion of the detected member is opposed to an output shaft that is regulated, and a detected member that is interlocked with the output shaft, and provided on the rotating shaft. And a second sensor that is provided to face the detected member and outputs a pulse signal in accordance with the rotation of the rotation shaft, the second sensor being output from the second sensor. Pulse counting means for counting the pulse signal; and rotating the output shaft from the first limit position toward the second limit position, and counting the pulse count from the first limit position to a position at which the reference signal is obtained. By means First position information creating means for creating first position information of the first sensor based on a pulse count value of the issued pulse signal; and when the reference signal is obtained during operation of the motor, the first position information is Pulse count correction means for correcting the pulse count value of the pulse signal by using the pulse count correction means.
[0018]
According to the present invention, the first position information of the first sensor is created in advance by the first position information creation unit, and the pulse count value calculated by the pulse count unit is corrected based on the value. The reflected pulse count value is corrected. For this reason, even if the mounting position of the first sensor is shifted, the pulse count does not shift. Therefore, for example, when the motor is applied to a wiper device, the reversal position of the blade does not shift for each product, and the reversal position accuracy can be maintained in common for the entire product. In addition, overrun of the blade can be prevented, and stoppage of the wiper arm due to mechanical abutment can be avoided. Therefore, it is possible to prevent the motor from being locked, generating abnormal noise, and stopping the wiper arm from being impacted, thereby improving the operational feeling and the durability of the apparatus.
[0019]
In the motor control device, the motor control device causes the output shaft to rotate from the second limit position toward the first limit position, and outputs the pulse from the second limit position to a position at which the reference signal is obtained. Second position information creating means for creating second position information of the first sensor based on the pulse count value of the pulse signal calculated by the counting means may be further provided.
[0020]
Further, in the motor control device, the motor control device further includes a storage unit for storing the first and second position information, and the pulse count correction unit includes the first and second position information stored in the storage unit. The pulse count value of the pulse signal may be corrected using two-position information.
[0021]
In addition, in the motor control device, when the output shaft rotates from the first limit position side toward the second limit position side, the pulse count correction unit may use the first position information to generate the pulse. The pulse count value of the signal is corrected, and when the output shaft rotates from the second limit position toward the first limit position, the pulse count value of the pulse signal is corrected using the second position information. You may do it.
[0022]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is an explanatory diagram showing a configuration of a motor unit including a motor to which the motor control method of the present invention is applied. The motor unit 1 in FIG. 1 is used as a drive source of a wiper device for a vehicle, and when a wiper blade (hereinafter, abbreviated as a blade) reaches a vertically inverted position, the rotation is switched between forward and reverse.
[0023]
The motor unit 1 includes a motor 2 and a gearbox 3. The rotation of a rotation shaft 4 of the motor 2 is reduced in the gearbox 3 and output to an output shaft 5. The rotating shaft 4 is rotatably supported by a bottomed cylindrical yoke 6, and is provided with an armature core 7 on which a coil is wound and a commutator 8. A plurality of permanent magnets 9 are fixed to the inner surface of the yoke 6. A brush 10 for power supply is in sliding contact with the commutator 8. The speed (the number of rotations) of the motor 2 is controlled by the amount of current supplied to the brush 10.
[0024]
A case frame 11 of the gear box 3 is attached to an opening edge of the yoke 6. The tip of the rotating shaft 4 projects from the yoke 6 and is housed in the case frame 11. A worm 12 is formed at the tip of the rotating shaft 4, and a worm gear 13 rotatably supported by the case frame 11 meshes with the worm 12. The worm gear 13 is integrally provided with a small-diameter first gear 14 on the same axis. The large diameter second gear 15 meshes with the first gear 14. The output shaft 5 rotatably supported by the case frame 11 is integrally attached to the second gear 15. Although not shown, another worm is formed on the rotating shaft 4 adjacent to the worm 12 in a direction opposite to the screw direction, and is formed by a reduction member similar to the worm gear 13 and the first gear 14. The power is transmitted to the second gear 15.
[0025]
The driving force of the motor 2 is output to the output shaft 5 in a decelerated state via the worm 12, the worm gear 13, the first gear 14, and the second gear 15. The output shaft 5 is connected to a link mechanism (not shown) of the wiper device. When the motor 2 operates, the link member is driven via the output shaft 5, and the wiper arm operates in conjunction with the other link members.
[0026]
A multi-pole magnetized magnet 16 (hereinafter abbreviated as magnet 16) is attached to the rotating shaft 4. On the other hand, a Hall IC 17 (second sensor) is provided in the case frame 11 so as to face the outer peripheral portion of the magnet 16. FIG. 2 is an explanatory diagram showing a relationship between the magnet 16 and the Hall IC 17 and an output signal (motor pulse) of the Hall IC 17.
[0027]
As shown in FIG. 2, two Hall ICs 17 (17A, 17B) are provided at positions having an angle difference of 90 degrees with respect to the center of the rotating shaft 4. In the motor 2, the magnet 16 is magnetized into six poles, and when the rotating shaft 4 makes one rotation, a pulse output for six periods is obtained from each Hall IC 17. From the Hall ICs 17A and 17B, pulse signals whose phases are shifted by 1/4 cycle are output as shown on the right side of FIG. Therefore, by detecting the timing of the appearance of the pulses from the Hall ICs 17A and 17B, the rotation direction of the rotary shaft 4 can be determined, whereby the forward path / return path of the wiper operation can be determined.
[0028]
In the Hall ICs 17A and 17B, the rotation speed of the rotating shaft 4 can be detected from one of the pulse output periods. There is a correlation between the rotation speed of the rotating shaft 4 and the blade speed based on the reduction ratio and the link operation ratio, and the blade speed can also be calculated from the rotating speed of the rotating shaft 4.
[0029]
A ring magnet 18 for detecting the absolute position of the blade is attached to the bottom surface of the second gear 15. A printed circuit board 19 is mounted on the case frame 11, and a Hall IC 20 (first sensor) is disposed on the printed circuit board 19 so as to face the ring magnet 18. The second gear 15 has a crank arm attached thereto as described above, and rotates about 180 degrees to reciprocate the blade. When the second gear 15 rotates and the blade comes to a preset reference position, the Hall IC 20 and the ring magnet 18 face each other, and a reference signal indicating an absolute position is output.
[0030]
With such a motor unit 1, the blade swings between a lower inversion position and an upper inversion position, and wipes rain, snow, and the like attached to the windshield. FIG. 3 is an explanatory diagram showing an operation range of the blade. During the wiping operation, the blade reciprocates within the wiping range between the vertically inverted positions shown by the solid lines in the figure. When the wiper is stopped, the blade moves to the storage position located below the lower turning position and is stored in the storage unit. The storage unit is provided inside a hood of a vehicle body (not shown).
[0031]
The blade is provided with an upper limit position (second limit position) and a lower limit position (first limit position) outside the vertically inverted position. These upper and lower limit positions are set mechanically in the motor unit 1. For example, a pin (not shown) protrudes from the case frame 11, and a groove (not shown) for accommodating the pin is provided in the second gear 15. This groove is recessed by an angle between the upper limit position and the lower limit position, and the pin moves in the groove as the second gear 15 rotates. When the pin comes to both ends of the groove, its movement is regulated, and that is the upper limit position and lower limit position of the blade.
[0032]
Further, a reference position at which a reference signal is output from the Hall IC 20 is provided at the center of the wiping range and slightly near the inverted position. FIG. 4 is an explanatory diagram showing a relationship between the Hall IC 20 and the ring magnet 18. As shown in FIG. As shown in FIG. 4, the ring magnet 18 has a two-pole configuration. When the blade comes to the reference position, the polarity of the ring magnet 18 changes (N → S), and a reference signal is output from the Hall IC 20. The position of the blade is detected by the reference signal and a pulse signal (motor pulse) from the Hall IC 17. FIG. 5 is an explanatory diagram showing the relationship between the motor pulse count number and the blade position.
[0033]
The output signal from the Hall IC 20 is used as a reference signal indicating the absolute position of the blade. That is, when this reference signal is obtained, it is determined that the blade has passed the reference position shown in FIG. On the other hand, the motor pulse from the Hall IC 17 is used as a relative position signal. The motor pulse is output in proportion to the rotation angle of the rotation shaft 4, and the pulse count value (accumulated number) corresponds to the rotation angle amount. Therefore, by counting the motor pulses after the reference signal is obtained, it is possible to know how much the blade has moved from the reference position.
[0034]
On the other hand, there is a possibility that a deviation occurs in the motor pulse count during blade operation due to some cause such as a wiping failure. Therefore, in this system, the motor pulse count value is reset when the reference signal is obtained. The reference position is a predetermined position, and the number of motor pulses obtained from the lower inversion position to the reference position has a fixed value. Therefore, the pulse count value at the reference position is set in advance as the reference value S, and when the reference signal is obtained, the pulse count value is reset to that value. As a result, the pulse count value is always corrected to the reference value S at the reference position, thereby preventing variation in blade position control due to a pulse shift.
[0035]
However, as described above, if an error occurs in the installation position of the Hall IC 20 serving as the reference position, the wiper position shifts as shown in FIGS. 10 and 11, causing various problems. Therefore, in the motor control method of the present invention, at the beginning of the motor installation, a reference position learning process for confirming the position of the Hall IC 20 is performed, and the absolute position of the reference position is grasped, and then the above-described blade position control is performed. .
[0036]
FIG. 6 is a flowchart showing an initial setting procedure when assembling the wiper device of the motor unit 1. In the control method of the present invention, at the time of assembling to the wiper device, after the motor initial position is set by the Hall IC 20 in the unit (step S1), mechanical attachment to the wiper device is performed (step S2). . Then, the reference position learning process is performed for each individual motor unit 1 (step S3), and after the variation in the sensor position is absorbed, the vehicle unit is set to the assembled state (step S4).
[0037]
Here, first, the motor unit 1 is set at the initial position for assembly, and the position of the output shaft 5 is adjusted to a constant state prior to mechanical assembly (step S1). The assembling initial position refers to the position of the output shaft 5 when assembling the link member of the wiper device and the motor unit 1, and a position rotated by a predetermined angle from the reference position according to the type of vehicle is set in advance. Therefore, before assembling the motor unit 1 to the wiper device, the motor 2 is once energized, and is driven and stopped by a predetermined number of pulses from the time when the reference signal is obtained. By this operation, the output shaft 5 stops at a position rotated by a predetermined angle from the reference position, and is set to the initial position for assembly.
[0038]
After setting the output shaft 5 at the initial position for assembly, the wiper device and the motor unit 1 are assembled (step S2). That is, the link member of the wiper device is set in a predetermined state, and the output shaft 5 set at the initial mounting position is attached thereto. Thus, the motor unit 1 is attached to the wiper device in a state where the blade position and the position of the output shaft 5 are related.
[0039]
After assembling the output shaft 5 to the wiper device at a predetermined position, a reference position learning process according to the present invention is performed (step S3). FIG. 7 is a block diagram illustrating a configuration of a control device that performs the reference position learning process. The control device includes a CPU 21 and an EEPROM 22, as shown in FIG. The CPU 21 receives a pulse signal from the Hall IC 17 and counts the number of pulses, a pulse count means 23, a first position information generating means 24 for generating first position information indicating the position of the Hall IC 20, and a second position information. Is provided.
[0040]
The first position information creating means 24 receives the reference signal signal from the Hall IC 20 and, when the output shaft 5 is rotated from the lower limit position to the upper limit position, the pulse count means from the lower limit position to the position where the reference signal is obtained. The first position information of the Hall IC 20 is created based on the pulse count value of the pulse signal calculated by 23. The second position information creating means 25 receives the reference signal signal from the Hall IC 20, and when the output shaft 5 is rotated from the upper limit position to the lower limit position, the pulse count means from the upper limit position to the position where the reference signal is obtained. The second position information of the Hall IC 20 is created based on the pulse count value of the pulse signal calculated by 23. The first position information and the second position information created by the first position information creating unit 24 and the second position information creating unit 25 are stored in the EEPROM 22 as a storage unit.
[0041]
Further, the CPU 21 is provided with a pulse count correction means 26 and a drive command means 27. The pulse count correction means 26 corrects the pulse count value using at least one of the first and second position information when the reference signal is obtained during the operation of the motor. The drive command means 27 controls the drive of the motor 2 based on the pulse count value of the motor 2.
[0042]
The following reference position learning processing is performed by such a control device. FIG. 8 is a flowchart showing the procedure of the reference position learning process. Here, first, the motor 2 is driven to rotate in the reverse direction by the drive command means 27 (step S11), and the blade is moved to the lower limit position (step S12). Next, the motor 2 is driven to rotate forward (step S13), and the blade is moved toward the upper limit position. At this time, the presence or absence of the input of the reference signal is monitored (step S14). If the reference signal has been obtained, the process proceeds to step S15, where the first position information creating means 24 stores the accumulated count value of the motor pulse at that time in the EEPROM 22. As a result, the distance (pulse count value) from the lower limit position to the reference position in the device is detected, and this becomes the first reference value (first position information) at the reference position.
[0043]
After obtaining the reference signal, the motor 2 is further driven to move the blade to the upper limit position (step S16). By reading the pulse count value when the blade has reached the upper limit position, the mechanical operating angle between the upper and lower limit positions of the blade can be detected. Then, after the blade reaches the upper limit position, the motor is reversely driven again (step S17), and the blade is moved toward the lower limit position. Also at this time, the presence or absence of the input of the reference signal is monitored (step S18). If the reference signal has been obtained, the process proceeds to step S19, where the second position information creating means 25 stores the accumulated count value of the motor pulse at that time in the EEPROM 22. As a result, the distance from the upper limit position to the reference position in the device can be calculated, and this becomes the second reference value (second position information). The first and second reference values may be written in a ROM area of a flash microcomputer used for the control device.
[0044]
After obtaining the reference signal, the motor 2 is further driven to move the blade to the lower limit position (step S20), and the routine exits. Thereby, the reference position learning process is completed, and information on the reference position unique to the device is obtained. After the reference position learning process, the process returns to the process of FIG. 6, and the wiper device is set to the vehicle body assembling position (step S4), and the routine exits. The wiper device to which the motor unit 1 has been attached and these processes have been completed is appropriately attached to the vehicle body. The initial assembly position may be set to the same state as the vehicle body installation position.
[0045]
FIGS. 9A and 9B are explanatory diagrams showing the relationship between the pulse count and the wiper position when the control method of the present invention is applied to the motor unit 1. FIG. 9A shows the case where the Hall IC 20 is at the regular position, and FIG. Shows a case where the Hall IC 20 is mounted at a shifted position. When the above-described learning process is not performed, a shift occurs in the wiper position as shown in FIG. On the other hand, in the motor that has performed the learning process, the pulse count value is reset to reflect the actual position of the Hall IC 20. For this reason, even if the mounting position of the Hall IC 20 is shifted, the wiper position does not shift.
[0046]
First, in the motor that has performed the learning process, the pulse count value is reset at the actual mounting position based on the first and second reference values stored in the EEPROM 22. As shown in FIG. 9A, if the Hall IC 20 is at the normal position (for example, 45 degrees from the lower inversion position), the pulse count correction unit 26 sets the pulse count value to the normal first reference value S. ₀ Is reset to During the operation of the wiper, if the pulse count value at the reference position is a normal value, the values are linearly integrated without interruption. If there is an error in the pulse count value, the correct value at the 45 ° position (the first reference value S) ₀ ), And the pulse count value is corrected.
[0047]
On the other hand, when the Hall IC 20 is not at the proper position (for example, 50 ° from the lower inversion position), the following is performed. In this case, the shifted mounting position (50 °) is detected in advance by the above-described learning process, and 50 ° is the reference position of the device. At this reference position, the pulse count value at the 50 ° position is equal to the first reference value S. ₁ And stored in the EEPROM 22. Then, as shown in FIG. 9B, when the reference signal is obtained from the Hall IC 20 at the mounting position, the pulse count corrector 26 corrects the pulse count value at the 50 ° position (the first reference value S). ₁ ) Is reset to Therefore, the pulse count value is thereafter accumulated without any error, and the wiper position is controlled without shifting even though the mounting position of the Hall IC 20 is shifted.
[0048]
For this reason, the reversal position of the blade does not shift for each product, and it is possible to maintain the reversal position accuracy commonly for the entire product. In addition, overrun of the blade can be prevented, and stoppage of the wiper arm due to mechanical abutment can be avoided. Therefore, it is possible to prevent the motor from being locked, generating abnormal noise, and stopping the wiper arm from being impacted, thereby improving the operational feeling and the durability of the apparatus.
[0049]
Note that, when the polarity of the Hall IC 20 changes from N to S and when the polarity changes from S to N, there may be a difference in the reference signal output position due to the hysteresis of the element. Therefore, contrary to the previous example, when the reference position is reached from the upper inversion position, the first reference value S ₁ When resetting is performed by using, there is a possibility that a pulse shift may occur due to the hysteresis. Therefore, in this case, if the reset is performed using the second reference value obtained in step S19, the pulse shift can be resolved.
[0050]
The present invention is not limited to the above embodiment, and it goes without saying that various modifications can be made without departing from the scope of the invention.
For example, the process of FIG. 8 assumes that the assembly initial position is on the lower limit position side of the reference position. However, the learning of the reference position can be performed by reversing the operation also on the upper limit position side. It is possible. That is, in step S11, the motor is normally driven to move the blade to the upper limit position side, and the actual mounting position of the Hall IC 20 can be learned by searching for the reference position therefrom. In the motor unit 1 described above, one Hall IC 20 is used as the second sensor, but the present invention is also applicable to a motor using a plurality of second sensors. In that case, the position of each sensor is individually recognized by the above-described learning process.
[0051]
In the above-described embodiment, the Hall IC is used as a sensor for obtaining the absolute position signal and the relative position signal. However, the type of the sensor is not limited to this, and an optical encoder using a photodiode or the like is used. Other types of sensors, such as an infrared sensor and an infrared sensor, may be used.
[0052]
Furthermore, an example in which the present invention is applied to a motor for a wiper device has been described, but the application object is not limited to this, and the present invention is used for electric components for vehicles such as an automobile tailgate, a sliding door, a power window, and a sunroof. It can also be applied to motors that use It should be noted that a motor that drives the motor to the limit position, such as a power window, can always use the abutting position to obtain a reset signal at an accurate position. In this regard, since the wiper device performs the forward / reverse rotation of the motor at the vertical reversal position where there is no mechanical restriction, a pulse shift is likely to occur, and the concept of overrun also occurs. Therefore, the learning process as described above is particularly effective in a wiper device. Further, the control method / apparatus of the present invention is applicable not only to automobiles but also to motors for various electric appliances.
[0053]
【The invention's effect】
According to the motor control method of the present invention, the output shaft is previously rotated from the first limit position toward the second limit position, and the pulse signal output by the second sensor from the first limit position to the position where the reference signal is obtained. Since the first position information of the first sensor is created based on the pulse count value of the first sensor, and the reference signal is obtained when the motor is operated, the pulse count value of the pulse signal is corrected using the first position information. The pulse count value is corrected to reflect the sensor position. For this reason, even if the mounting position of the first sensor is shifted, the pulse count does not shift.
[0054]
Therefore, for example, when the motor is applied to a wiper device, the reversal position of the blade does not shift for each product, and the reversal position accuracy can be maintained in common for the entire product. In addition, overrun of the blade can be prevented, and stoppage of the wiper arm due to mechanical abutment can be avoided. Therefore, it is possible to prevent the motor from being locked, generating abnormal noise, and stopping the wiper arm from being impacted, thereby improving the operational feeling and the durability of the apparatus.
[0055]
Further, according to the motor control device of the present invention, the first position information of the first sensor is created in advance by the first position information creation unit, and the pulse count value calculated by the pulse count unit is corrected based on the created value. The pulse count value is corrected to reflect the actual sensor position. For this reason, even if the mounting position of the first sensor is shifted, the pulse count does not shift.
[0056]
Therefore, for example, when a motor using the motor control device is applied to a wiper device, the reversal position of the blade does not shift for each product, and the reversal position accuracy can be maintained in common for the entire product. In addition, overrun of the blade can be prevented, and stoppage of the wiper arm due to mechanical abutment can be avoided. Therefore, it is possible to prevent the motor from being locked, generating abnormal noise, and stopping the wiper arm from being impacted, thereby improving the operational feeling and the durability of the apparatus.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram showing a configuration of a motor unit including a motor to which a motor control method according to the present invention is applied.
FIG. 2 is an explanatory diagram showing a relationship between a magnet and a Hall IC and an output signal (motor pulse) of the Hall IC.
FIG. 3 is an explanatory diagram showing an operating range of a blade.
FIG. 4 is an explanatory diagram showing a relationship between a Hall IC and a ring magnet.
FIG. 5 is an explanatory diagram showing a relationship between a motor pulse count number and a blade position.
FIG. 6 is a flowchart illustrating a procedure of initial setting of a motor unit.
FIG. 7 is a block diagram illustrating a configuration of a control device that performs a reference position learning process.
FIG. 8 is a flowchart illustrating a procedure of a reference position learning process.
9A and 9B are explanatory diagrams showing a relationship between a pulse count and a wiper position when the control method of the present invention is applied to the motor unit of FIG. 1; FIG. 9A shows a case where the Hall IC is at a regular position; (b) shows a case where the Hall IC is mounted at a shifted position.
FIG. 10 is an explanatory diagram showing a configuration for obtaining a pulse reset signal.
11A and 11B are explanatory diagrams showing a relationship between a pulse count and a wiper position. FIG. 11A shows a case where the sensor is at a regular position, and FIG. 11B shows a case where the sensor is at a position shifted by an error. I have.
[Explanation of symbols]
1 Motor unit
2 motor
3 Gearbox
4 Rotation axis
5 Output shaft
6 York
7 Armature core
8 commutator
9 permanent magnet
10 brushes
11 Case frame
12 Warm
13 Worm gear
14 First gear
15 Second gear
16 Multi-pole magnetized magnet
17, 17A, 17B Hall IC
18 Ring magnet
19 Printed circuit board
20 Hall IC
21 CPU
22 EEPROM (storage means)
23 pulse counting means
24 first position information creating means
25 A second position information creating means is provided.
26 Pulse count correction means
27 Drive command means
51 Sensor magnet
52 sensors
S reference value
S ₀ First reference value
S ₁ First reference value

Claims (8)

A motor main body having a rotating shaft, an output shaft through which a rotation of the rotating shaft is transmitted at a reduced speed via a speed reduction mechanism, and a rotation angle regulated between a first limit position and a second limit position; A first sensor that is provided to face a detected member that is interlocked with a shaft, and that outputs a reference signal when a predetermined portion of the detected member faces, and a first sensor that is provided to face a detected member provided on the rotating shaft. And a second sensor that outputs a pulse signal in accordance with the rotation of the rotation shaft, the control method of the motor comprising:
The output shaft is rotated from the first limit position toward the second limit position, and a pulse count value of the pulse signal output by the second sensor from the first limit position to a position where the reference signal is obtained. Creating first position information of the first sensor based on
When the reference signal is obtained during the operation of the motor, a pulse count value of the pulse signal is corrected using the first position information. 2. The motor control method according to claim 1, wherein the output shaft is rotated from the second limit position toward the first limit position, and the second sensor is rotated from the second limit position to a position where the reference signal is obtained. Generating the second position information of the first sensor based on a pulse count value of the pulse signal output by the motor control method. 3. The motor control method according to claim 2, wherein when the output shaft rotates from the first limit position to the second limit position, a pulse count value of the pulse signal is determined using the first position information. And correcting the pulse count value of the pulse signal using the second position information when the output shaft rotates from the second limit position toward the first limit position. Motor control method. 4. The motor control method according to claim 1, wherein the detected member is a magnet, and the first and second sensors are Hall ICs. 5. A motor main body having a rotating shaft, an output shaft through which a rotation of the rotating shaft is transmitted at a reduced speed via a speed reduction mechanism, and a rotation angle regulated between a first limit position and a second limit position; A first sensor that is provided to face a detected member that is interlocked with a shaft, and that outputs a reference signal when a predetermined portion of the detected member faces, and a first sensor that is provided to face a detected member provided on the rotating shaft. And a second sensor that outputs a pulse signal in accordance with the rotation of the rotating shaft, a motor control device,
Pulse counting means for counting the pulse signal output from the second sensor;
The output shaft is rotated from the first limit position toward the second limit position, and the pulse count of the pulse signal calculated by the pulse counting means from the first limit position to a position where the reference signal is obtained. First position information creating means for creating first position information of the first sensor based on the value;
A motor control device, comprising: pulse count correction means for correcting a pulse count value of the pulse signal using the first position information when the reference signal is obtained during the operation of the motor. 6. The motor control device according to claim 5, wherein the motor control device further rotates the output shaft from the second limit position toward the first limit position, and obtains the reference signal from the second limit position. A motor control device, comprising: second position information creating means for creating second position information of the first sensor based on a pulse count value of the pulse signal calculated by the pulse counting means up to a position. 7. The motor control device according to claim 6, wherein the motor control device further includes a storage unit that stores the first and second position information, and the pulse count correction unit stores the first and second position information. A motor control device, wherein a pulse count value of the pulse signal is corrected using first and second position information. 8. The motor control device according to claim 6, wherein the pulse count correction unit uses the first position information when the output shaft rotates from the first limit position to the second limit position. And correcting the pulse count value of the pulse signal. When the output shaft rotates from the second limit position toward the first limit position, the pulse count of the pulse signal is calculated using the second position information. A motor control device for correcting a value.

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