JP2009067261A - Wiper system and wiper control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize smooth wiper action with no variation by reducing a control error caused by deflection or a play of a wiper arm or a link mechanism. <P>SOLUTION: This wiper system 1 is connected to output shafts 18a, 18b of motors 3a, 3b through the link mechanisms 14a, 14b, and has pivot shafts 12a, 12b in which the wiper arms 13a, 13b are mounted. An MR sensor 22 which detects rotational angle of the pivot shafts and outputs a detecting signal when the wiper arms 13a, 13b reach a lower reversing position is disposed adjacent to the pivot shafts 12a, 12b to detect an absolute position of the wiper arms 13a, 13b at the rear stage of the link mechanisms 14a, 14b. A stress sensor 24 which detects load applied to the pivot shafts is mounted on the pivot shafts 12a, 12b, thus detecting lock or chattering in the wiper arms 13a, 13b. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a control technology for a vehicle wiper system, and more particularly to a wiper system and a wiper control method capable of reducing a control error or the like caused by bending or backlash of a wiper arm or a link mechanism.

  In recent years, in a wiper system for a vehicle such as an automobile, particularly a wiper system of the opposite wiping type (opposite type), each wiper arm on the driver's seat side and the passenger's seat side is individually motor-driven as disclosed in JP-A-11-301417. The method is adopted. In such a wiper system, the motors are individually controlled while looking at the position angle of each wiper arm so that the left and right wiper blades (hereinafter abbreviated as blades as appropriate) do not interfere on the wiping surface. For example, in the device described in the above publication, the position angle of the left and right blades is constantly monitored by the wiper control device. A target angle difference is set in advance between both blades, and the left and right motors are individually speed controlled so that the difference between the target angle difference and the measured angle difference is reduced while referring to the position angle of the other blade. .

In such a wiper system, a so-called electromechanically integrated motor unit in which a motor and its control circuit are integrated is often used. For example, Patent Document 2 describes a wiper system in which a wiper motor and an electronic control unit form one constituent unit. The wiper system of Patent Document 2 is a counter wiping type, and the wiper arm is driven by the first and second wiper motors, in order to detect the absolute rotation position and the relative rotation position of the output shaft on the second wiper motor side. The sensor device is arranged. A detection signal from the sensor device is sent to a control unit provided in the first wiper motor, and the rotation position and rotation speed of the output shaft on the first wiper motor side are controlled based on the data.
Japanese Patent Laid-Open No. 11-301417 Special table 2004-521004 gazette

  On the other hand, in the conventional wiper system as described above, as shown in FIG. 6, the sensor device for detecting the operation of the wiper motor 51 is usually attached to the output shaft such as the worm shaft 52 of the speed reduction mechanism or the armature shaft 53 of the motor. It is done. For example, in the sensor device 54 attached near the worm shaft 52, the absolute position of the wiper arm 55 is detected by detecting the absolute rotational position of the worm shaft 52. The sensor device 56 attached to the armature shaft 53 detects the relative rotation position (rotation angle) of the armature shaft 53, thereby detecting the relative position from the absolute position of the wiper arm 55, and based on the detection data of both. As a result, the current position and operating speed of the wiper arm 55 are grasped.

  However, in such a wiper system, since the sensor devices 54 and 56 are attached to the worm shaft 52 and the armature shaft 53, a wiper operation that occurs in a portion after the motor, such as bending or backlash of the wiper arm 55 or the link mechanism 57, etc. Unable to detect the effect of variable factors. For this reason, there is a difference between the actual operation of the wiper system and the control assumption, and there is a problem that an unexpected control error may occur in the wiper operation.

  For example, when the arm operation is locked due to snow damage or a large external force is applied to the arm, the relationship between the rotation angle of the worm shaft 52 and the arm position may become unmatched with the design value due to the bending of the arm. . Thus, if the wiper operation is controlled in a situation where the arm position is not accurately grasped, there is a possibility that problems such as contact between the blades 58 and instability of the reversal position may occur. Further, when the wiper arm 55 and the blade 58 have low rigidity, the wiper arm 55 and the blade 58 are bent by an impact during the reversing operation, and if the control is performed without assuming that, the reversing operation is not performed at the expected position, and the There was also the problem of causing a run or short run.

  Furthermore, chattering of the wiper arm 55 and the blade 58 does not affect the motor operation, and thus the chatter phenomenon cannot be detected by the sensor devices 54 and 56 that detect rotation. For this reason, there has been a problem that fine wiper operation control such as appropriately changing the motor speed in accordance with chattering cannot be performed.

  An object of the present invention is to reduce a control error caused by bending or play of a wiper arm or a link mechanism, and to realize a smooth wiper operation without variation.

  The wiper system of the present invention includes an electric motor, a pivot shaft connected to the output shaft of the electric motor via a power transmission mechanism, a wiper arm attached to the pivot shaft, and a wiper blade attached to the wiper arm. A wiper system having an angle sensor that detects a rotation angle of the pivot shaft and outputs a predetermined detection signal when the wiper arm is in a specific position, in the vicinity of the pivot shaft. It is characterized by. In this case, as the angle sensor, an MR sensor arranged to face a sensor magnet attached to the pivot shaft may be used.

  In the present invention, since the angle sensor for detecting the wiper arm position is disposed in the vicinity of the pivot shaft located at the rear stage of the power transmission mechanism, the position of the wiper arm is not affected by the deflection or backlash of the power transmission mechanism. Detection can be performed, and the control error of the wiper arm due to the deflection or backlash of the power transmission mechanism can be reduced.

  In the wiper system, a load sensor for detecting a load applied to the pivot shaft may be provided on the pivot shaft, and a strain gauge may be attached to the pivot shaft as the load sensor.

  On the other hand, the wiper control method of the present invention includes an electric motor, a pivot shaft connected to the output shaft of the electric motor via a power transmission mechanism, a wiper arm attached to the pivot shaft, and attached to the wiper arm. A wiper system control method comprising a wiper blade, wherein the wiper arm is disposed in the vicinity of the pivot shaft positioned downstream of the power transmission mechanism, detects a rotation angle of the pivot shaft, and the wiper arm is in a specific position. The absolute position of the wiper arm is detected by an angle sensor that outputs a predetermined detection signal when present.

  In the present invention, since the absolute position of the wiper arm is detected by the angle sensor for detecting the wiper arm position disposed in the vicinity of the pivot shaft, the absolute position of the wiper arm is detected without being affected by the deflection or backlash of the power transmission mechanism. Thus, the wiper arm control error due to the deflection or backlash of the power transmission mechanism can be reduced.

  In the wiper control method, a load applied to the pivot shaft is detected by a load sensor provided on the pivot shaft, and when the load exceeds a predetermined threshold, it is determined that the operation of the wiper arm is locked. Also good. Further, when the time change of the load applied to the pivot shaft exceeds a predetermined value, it may be determined that a chatter phenomenon has occurred in the wiper arm or the wiper blade.

  According to the wiper system of the present invention, the rotation angle of the pivot shaft is detected in the vicinity of the pivot shaft connected to the output shaft of the electric motor via the power transmission mechanism and attached with the wiper arm, and the wiper arm exists at a specific position. Since an angle sensor that outputs a predetermined detection signal is disposed sometimes, it is possible to detect the position of the wiper arm without being affected by the deflection or backlash of the power transmission mechanism. For this reason, it is possible to reduce the control error of the wiper arm due to the deflection or backlash of the power transmission mechanism, and it is possible to realize a smoother and more uniform wiper operation.

  According to the wiper control method of the present invention, the rotation angle of the pivot shaft is detected in the vicinity of the pivot shaft connected to the output shaft of the electric motor via the power transmission mechanism and the wiper arm is mounted, and the wiper arm is present at a specific position. In addition, an angle sensor that outputs a predetermined detection signal is arranged, and the absolute position of the wiper arm is detected by this angle sensor, so that the position of the wiper arm can be detected without being affected by the deflection or backlash of the power transmission mechanism. Can be performed. For this reason, it is possible to reduce the control error of the wiper arm due to the deflection or backlash of the power transmission mechanism, and it is possible to realize a smoother and more uniform wiper operation.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is an explanatory diagram showing an overall configuration of a wiper system driven by a control device / control method according to an embodiment of the present invention. 1 includes a wiper blade 2a (first wiper blade) and 2b (second wiper blade) on a driver side (hereinafter abbreviated as DR side) and a passenger seat side (hereinafter abbreviated as AS side). ) Is a so-called counter-wiping type wiper device. A DR side motor (first motor) 3a and an AS side motor (second motor) 3b (hereinafter abbreviated as motors 3a and 3b) are separately provided on the DR side and the AS side, respectively. The blades 2a and 2b are driven by electric motors 3a and 3b with a speed reduction mechanism, and face each other between an upper reversal position set at both ends of the windshield and a lower reversal position set at the center of the lower end of the windshield. Wiping operation is performed. Note that “a, b” in the reference numerals indicates members and portions related to the DR side and the AS side, respectively.

  A blade rubber member (not shown) is attached to the blades 2a and 2b. The rubber member is brought into close contact with the windshield of the vehicle and moved to be present in the wiping areas 11a and 11b indicated by broken lines in FIG. Water droplets to be wiped away. The blades 2a and 2b are supported by wiper arms 13a and 13b fixed to the ends of the pivot shafts 12a and 12b. The blades 2a and 2b are swung left and right by link mechanisms (power transmission mechanisms) 14a and 14b driven by the motors 3a and 3b. Do dynamic exercise. The link mechanisms 14a and 14b include a link mechanism including motors 3a and 3b, crank arms 15a and 15b, connecting rods 16a and 16b, drive levers 17a and 17b, and wiper arms 13a and 13b.

  Drive levers 17a and 17b are further attached to the pivot shafts 12a and 12b to which the wiper arms 13a and 13b are fixed. Connecting rods 16a and 16b are attached to the end portions of the drive levers 17a and 17b. The other ends of the connecting rods 16a and 16b are connected to the tip ends of crank arms 15a and 15b fixed to the output shafts 18a and 18b of the motors 3a and 3b. When the motors 3a, 3b are driven and the output shafts 18a, 18b rotate, the crank arms 15a, 15b rotate, and this movement is transmitted to the drive levers 17a, 17b via the connecting rods 16a, 16b. Thereby, the rotational motion of the motors 3a and 3b is converted into the swing motion of the wiper arms 13a and 13b, and the blades 2a and 2b reciprocate between the upside down positions.

  FIG. 2 is an explanatory diagram showing the sensor arrangement of the wiper system 1. 2 shows only the configuration of the DR side motor 3a, the motor 3b has the same configuration. The motors 3a and 3b are accommodated in the motor units 4a and 4b, and pulse sensors 21a and 21b for outputting relative position signals (motor pulses) indicating the movement amounts of the wiper arms 13a and 13b are provided in the motor units 4a and 4b. Is provided. As the pulse sensors 21a and 21b, for example, a magnetic sensor using a multi-pole magnetized magnet and a Hall element is used, and a number of pulse signals proportional to the motor rotation angle are output. Further, as shown in FIG. 2, in the wiper system 1, unlike the conventional wiper system, the MR sensor 22 for detecting the absolute position of the wiper arm is arranged on the pivot shafts 12a and 12b.

  FIG. 3 is an explanatory diagram showing a configuration in the vicinity of the pivot shaft 12 a in the wiper system 1. As described above, the vicinity of the pivot shaft 12b has the same configuration. As shown in FIG. 3, a sensor magnet 23 is attached to the bottom of the pivot shaft 12a. An MR sensor 22 is disposed below the sensor magnet 23 so as to face the sensor magnet 23. The sensor magnet 23 is a disk-shaped permanent magnet, and is magnetized so that the magnetic field strength changes along the circumferential direction. Here, the magnetic field intensity is maximized when the wiper arm 13a comes to the lower inversion position, and the output voltage value from the MR sensor 22 is maximized. That is, the MR sensor 22 outputs a signal having a voltage equal to or higher than a predetermined value when the wiper arm 13a comes to the lower inversion position (specific position). Thereby, it can be grasped that the wiper arm 13a exists at a specific position set in advance in the wiping area, and the absolute position of the wiper arm 13a can be detected.

  Further, a stress sensor 24 (for example, a strain gauge) is attached to the pivot shaft 12a as a load sensor for measuring a load applied to the pivot shaft 12a. When a torsional stress is generated on the pivot shaft, the stress sensor 24 outputs a voltage signal corresponding to the value. The stress sensor 24 outputs a detection signal according to the load applied to the pivot shaft 12a even during normal control. However, when the wiper arm 13a is locked due to snow damage or the like, a load is applied to the pivot shaft 12a and a large torsional stress is generated. In some cases, a detection signal having a value corresponding thereto is output.

  Such detection signals of various sensors are sent to control microcomputers 5a (first control circuit) and 5b (second control circuit) arranged in the vicinity of the pivot shafts 12a and 12b. As shown in FIG. 3, the control microcomputer 5 a is placed on the circuit board 25 and is housed in the protective case 26 together with the circuit board 25. The circuit board 25 is connected to a motor output line 27, a communication line 7, a power line 28, and the like. As shown in FIG. 4, in the wiper system 1, in addition to the control microcomputers 5a and 5b, the MR sensor 22, and the stress sensor 24, the sensor input circuit 29 and the voltage sensor 30 are arranged on the pivot shafts 12a and 12b side. Various control-related components such as a switch input / output circuit 31, a communication circuit 32, and a motor drive circuit 33 are arranged. Further, pulse sensors 21a and 21b and a motor temperature sensor 34 are arranged on the motors 3a and 3b side.

  In the wiper system 1, the DR-side control microcomputer 5 a is connected to a switch controller 6, which is a vehicle-side control device, via an in-vehicle LAN 9. Switch information such as ON / OFF of the wiper switch, Lo, Hi, INT (intermittent operation), vehicle speed information, and the like are input from the switch controller 6 to the control microcomputer 5a. The control microcomputers 5a and 5b are connected by a communication line 7. In the wiper system 1, the motor 3a connected to the switch controller 6 is on the master side, and the motor 3b connected to the motor 3a via the communication line 7 is on the slave side, and both motors 3a, 5b are controlled by the control microcomputers 5a, 5b. The control 3b is performed.

  Each control microcomputer 5a, 5b acquires the arm position information of the other party via the communication line 7. Here, the relative position signal described above is a pulse signal generated with the rotation of the motor, and a pulse number proportional to the rotation angle of the motor is output. On the other hand, the absolute position signal is a single signal that is generated when the wiper arms 13a and 13b come to a specific position (for example, the lower inversion position). Since the rotational speeds of the motors 3a and 3b and the rotational speeds of the output shafts 18a and 18b are in a fixed relationship based on the reduction ratio, the rotational angles of the output shafts 18a and 18b can be calculated from the number of pulses. On the other hand, the rotation angle of the output shafts 18a and 18b and the movement angle of the wiper arms 13a and 13b have a certain correlation based on the link mechanism of the link mechanisms 14a and 14b. Therefore, the movement angles of the wiper arms 13a and 13b can be known by integrating the number of pulses of the relative position signal.

  Therefore, the control microcomputers 5a and 5b detect the current positions of the wiper arms 13a and 13b based on the combination of the absolute position signal indicating the arm position and the number of pulses. The control microcomputers 5a and 5b exchange the position information via the communication line 7 and synchronously drive the motors 3a and 3b based on the positional relationship between the two wiper arms. That is, first, the control microcomputers 5a and 5b control the motors 3a and 3b in forward and reverse directions based on the arm positions on their own side. As a result, the blades 2a and 2b perform a reciprocating wiping operation between the upside down positions. At the same time, the control microcomputers 5a and 5b control the motors 3a and 3b based on the position information of the wiper arms 13a and 13b, and control the wiper system 1 so that the blades do not interfere with each other and the angle difference does not increase.

  Here, in the wiper system 1 according to the present invention, since the control microcomputers 5a and 5b are disposed in the vicinity of the pivot shafts 12a and 12b, the output signals of the MR sensor 22 and the stress sensor 24 are not easily affected by the magnetic field of the motor. . Usually, since the output signal of the MR sensor 22 and the like is based on a minute change in voltage, it is easily affected by noise and a magnetic field, and it is preferable that the distance between the sensor and the microcomputer is as short as possible. In that respect, the conventional electromechanical integrated motor is close to the control microcomputer and the motor, and is easily affected by the magnetic field. Further, when the MR sensor 22 is arranged in the vicinity of the pivot shafts 12a and 12b and the output signal thereof is received by a conventional motor-integrated motor, the distance between the sensor and the microcomputer becomes long and is affected by noise. It becomes easy. For this reason, in the wiper system 1, the drive circuit and the control microcomputers 5a and 5b are arranged in the vicinity of the pivot shafts 12a and 12b to suppress the deterioration of the output signal from each sensor and to improve the control accuracy.

  On the other hand, even in the wiper system 1, it is unavoidable that the wiper arms 13a and 13b and the link mechanisms 14a and 14b are bent or loose. As described above, in the conventional wiper system, since the wiper arm and the like exist before the sensor, a control error may occur during snowfall or the like due to the bending or backlash. Further, chatter of the wiper arms 13a and 13b and the blades 2a and 2b is not detected at all in the conventional wiper system.

  On the other hand, in the wiper system 1, since the MR sensor 22 for detecting the wiper arm absolute position is disposed on the pivot shafts 12a and 12b, the wiper arm 13a is not affected by the bending or backlash of the link mechanisms 14a and 14b. , 13b can be detected. That is, in this case, the pivot shafts 12a and 12b are controlled by the sensor instead of the output shafts 18a and 18b, and the motors 3a and 3b are excluded from the influence of the bending and backlash of the link mechanism located in the front stage of the sensor. Can be controlled. For this reason, it is possible to reduce the control error of the wiper arms 13a and 13b due to bending and backlash, and it is possible to realize a smoother wiper operation without variation.

  In the conventional wiper system, when the setting of the link mechanism is changed, it is necessary to change the control map in the control microcomputers 5a and 5b, and when corresponding to other vehicle types, it is necessary to individually adjust the control mode. is there. On the other hand, in the wiper system 1, when detecting the absolute position of the wiper arm, there is no influence due to the change of the link setting, so that the behavior of the arm can be controlled without being aware of the change of the link setting. For this reason, it becomes easy to expand to other vehicle types, and it becomes possible to provide a wiper system with high versatility and excellent design freedom.

  Further, when an external force is applied to the wiper arms 13a and 13b due to snow damage or the like, the arm is bent by the external force, and stress corresponding to the force is generated on the pivot shafts 12a and 12b. In the wiper system 1, such a pivot shaft stress is detected by the stress sensor 24, and the control microcomputers 5a and 5b utilize this data as one of the control data. Usually, a force in the torsional direction acts on the pivot shafts 12a and 12b depending on the position and speed of the wiper arms 13a and 13b due to the sliding resistance between the blade rubber and the windshield. At this time, the stress generated in the pivot shafts 12a and 12b can be assumed based on the arm position, the motor rotation speed, the control duty value, and the like. The wiper system 1 predicts and calculates this as the pivot shaft stress during normal control. ing.

  However, when the wiper arms 13a and 13b are locked due to snowfall or the like, the rotational driving force of the motors 3a and 3b is thereby blocked, and a large torsional stress is generated on the pivot shafts 12a and 12b. Further, when chatter occurs in the blades 2a and 2b and the wiper arms 13a and 13b, the stress generated in the pivot shafts 12a and 12b changes irregularly accordingly. That is, when the arm is locked or chatter occurs, the pivot shaft stress is different from that during normal control. Therefore, by constantly monitoring the pivot shaft stress and comparing the detected value with the assumed value during normal control, the current state of the wiper arms 13a and 13b can be grasped, and lock and chatter can be accurately detected. Is possible.

  FIG. 5 is an explanatory diagram showing the relationship between the rotation angle of the pivot shafts 12a and 12b and the pivot shaft stress. As indicated by a broken line in FIG. 5, in a state where a normal wiping operation is performed, the pivot shaft stress periodically changes according to the rotation angles of the pivot shafts 12a and 12b. On the other hand, as shown by the solid line in FIG. 5, when the wiper arms 13a and 13b are locked, the pivot shaft stress suddenly increases from that point. Therefore, in the wiper system 1, a lock determination threshold value (a dashed line in FIG. 5) is set in consideration of a predetermined lock torque width with respect to an assumed pivot shaft stress value during normal control, and the pivot shaft stress exceeds that. In this case, it is determined that a lock has occurred. Thereby, it is possible to detect the lock of the wiper arms 13a and 13b without being affected by the bending or backlash of the link mechanisms 14a and 14b, and quick control response (for example, motor stop, reverse rotation, etc.) by the early lock detection. It becomes possible.

  Further, when chatter occurs in the blades 2a and 2b and the wiper arms 13a and 13b, the pivot shaft stress changes irregularly as shown by a two-dot chain line in FIG. For this reason, it is possible to detect chatter by capturing the temporal change in the pivot shaft stress and comparing it with the temporal change in stress during normal control. For example, the number of changes (change frequency) in which the pivot shaft stress changes by a predetermined width W or more per unit time is detected, and when it exceeds a predetermined threshold, it is determined that chattering has occurred. As described above, the conventional wiper system cannot detect the chatter phenomenon and does not perform control corresponding to chatter. On the other hand, in the wiper system 1, since the sensors are arranged on the pivot shafts 12a and 12b that are directly affected by chatter, the chatter phenomenon can be accurately grasped and control response corresponding to chatter (for example, , Changes in the motor speed, etc.).

It goes without saying that the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the invention.
For example, in the above-described embodiment, an example in which the MR sensor is used for detecting the absolute position of the wiper arms 13a and 13b has been shown. However, as an angle sensor for detecting the rotation angle of the pivot shafts 12a and 12b, For example, a rotary encoder or a potentiometer can be used. Moreover, although the example which used the lower inversion position was shown as a point of the absolute position detection of the wiper arms 13a and 13b, the absolute position detection point is not limited to this, and an upper inversion position or a predetermined angle position set in advance is used It is also possible to do.
In the above embodiment, the counter-wiping type wiper device is used. However, the present invention can also be used when two wiper arms are operated by one motor.

It is explanatory drawing which shows the whole structure of the wiper system which is one Example of this invention. It is explanatory drawing which shows sensor arrangement | positioning of the wiper system of FIG. It is explanatory drawing which shows the structure of the vicinity of the pivot axis | shaft in the wiper system of FIG. It is explanatory drawing which shows the control system structure in the wiper system of this invention. It is explanatory drawing which shows the relationship between the rotation angle of a pivot axis | shaft, and pivot axis | shaft stress. It is explanatory drawing which shows sensor arrangement | positioning of the conventional wiper system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Wiper system 2a, 2b Wiper blade 3a, 3b Motor 4a, 4b Motor unit 5a, 5b Control microcomputer 6 Switch controller 7 Communication line 9 Car interior LAN
11a, 11b Wiping areas 12a, 12b Pivot shafts 13a, 13b Wiper arms 14a, 14b Link mechanism (power transmission mechanism)
15a, 15b Crank arms 16a, 16b Connecting rods 17a, 17b Drive levers 18a, 18b Output shafts 21a, 21b Pulse sensor 22 MR sensor (angle sensor)
23 Sensor magnet 24 Stress sensor (load sensor)
25 circuit board 26 protective case 27 motor output line 28 power supply line 29 sensor input circuit 30 voltage sensor 31 switch input / output circuit 32 communication circuit 33 motor drive circuit 34 motor temperature sensor 51 wiper motor 52 worm shaft 53 amateur shaft 54 sensor device 55 wiper arm 56 Sensor device 57 Link mechanism 58 Blade

Claims (7)

A wiper system comprising: an electric motor; a pivot shaft connected to the output shaft of the electric motor via a power transmission mechanism; a wiper arm attached to the pivot shaft; and a wiper blade attached to the wiper arm. Because
A wiper system characterized in that an angle sensor that detects a rotation angle of the pivot shaft and outputs a predetermined detection signal when the wiper arm exists at a specific position is disposed in the vicinity of the pivot shaft.   2. The wiper system according to claim 1, wherein the angle sensor is an MR sensor disposed to face a sensor magnet attached to the pivot shaft.   2. The wiper system according to claim 1, wherein a load sensor for detecting a load applied to the pivot shaft is provided on the pivot shaft.   4. The wiper system according to claim 3, wherein the load sensor is a strain gauge attached to the pivot shaft. A wiper system comprising: an electric motor; a pivot shaft connected to the output shaft of the electric motor via a power transmission mechanism; a wiper arm attached to the pivot shaft; and a wiper blade attached to the wiper arm. Control method,
An absolute position of the wiper arm is detected by an angle sensor that is arranged in the vicinity of the pivot shaft, detects a rotation angle of the pivot shaft, and outputs a predetermined detection signal when the wiper arm is in a specific position. Wiper control method.   6. The wiper control method according to claim 5, wherein a load applied to the pivot shaft is detected by a load sensor provided on the pivot shaft, and when the load exceeds a predetermined threshold value, it is determined that the operation of the wiper arm is locked. A wiper control method characterized by:   7. The wiper control method according to claim 5 or 6, wherein when a temporal change in a load applied to the pivot shaft exceeds a predetermined value, it is determined that a chatter phenomenon has occurred in the wiper arm or the wiper blade. Control method.

Images