JP5184395B2 - Wiper control method and wiper control device - Google Patents

Description

  The present invention relates to a control method and a control device for an automobile wiper device, and more particularly to a control mode for suppressing overrun of a wiper blade in an upside down position.

  2. Description of the Related Art Conventionally, in a wiper device for an automobile, a wiper that detects the current position of a wiper blade (hereinafter abbreviated as a blade) on a glass surface and performs a reciprocating wiping operation between the upside down position of the blade based on the detected data. The system is widely used. For example, Patent Document 1 describes a wiper device in which blades on the driver's seat side and the passenger's seat side are driven by independent motors, and each motor is feedback-controlled based on each current blade position.

  On the other hand, in such a wiper device, in order to improve the accuracy of the wiper wiping cycle, a method of controlling the motor using the elapsed time from the reverse position is known. In this case, for example, the elapsed time from the lower inversion position and the blade position (angle) are related in advance, and the current blade position is fed back to control the drive of the motor. In this case, if a delay occurs in the wiper operation in the first half of the one-way wiping operation, the output of the motor is increased in order to recover this delay in the second half of the operation. Thereby, the delay until now is recovered in the second half of the operation, and a predetermined wiping cycle is maintained.

JP 2002-264776

  However, in a wiper device for automobiles, the wiper operation speed is greatly reduced, such as when the operation load is large, such as during snowfall, or when the battery voltage is low, and a large operation delay occurs in the first half of the one-way wiping operation. There is a case. When such a delay occurs, in the wiper device adopting the control mode as described above, the output of the motor is greatly increased to recover this in the latter half of the operation. As a result, the blade speed immediately before the reversing position becomes too fast, and the blade cannot be stopped at the predetermined reversing position, which causes overrun.

  An object of the present invention is to control a wiper device so that a blade does not overrun during reversal even if an operation delay occurs in the first half of a one-way wiping operation due to a high load or the like.

The wiper control method of the present invention includes a wiper blade disposed on a wiping surface, and an electric motor for reciprocating the wiper blade on the wiping surface, and the electric motor is disposed on the wiping region. A wiper device control method in which drive control is performed based on a target rotational speed set corresponding to an elapsed time from a set reference position, wherein the wiper blade corresponds to the elapsed time. when it does not reach the set target position Te, the target speed is driven and controlled based on a preset correction value into the corrected target rotational speed obtained by adding to the previously said corrected target rotational speed to the target rotational speed If the elapsed greater than the upper limit rotational speed obtained by adding a correction addition upper limit value set in correspondence with the time, the set the upper limit rotation speed as the final target speed to actually drive the electric motor Wherein the correction when the target speed is less than the upper limit rotational speed, and sets the corrected target rotational speed as the final target rotational speed.

  In the present invention, when the corrected target rotational speed is larger than the upper limit rotational speed, by setting the upper limit rotational speed as the final target rotational speed, an increase in the motor rotational speed is suppressed, and the blade speed at the time of reversal is reduced. It is suppressed. Thereby, even when the operation of the wiper blade is delayed and the motor rotational speed is increased to recover it, the motor rotational speed in the vicinity of the reverse position does not become excessive, and the occurrence of overrun is suppressed.

In the wiper control method, the reference position of the elapsed time may be set as a lower reverse position of the wiper blade.

On the other hand, the wiper control device of the present invention includes a wiper blade disposed on a wiping surface, and an electric motor for reciprocating the wiper blade on the wiping surface, and the electric motor includes the wiping region. A wiper device control device that is driven and controlled based on a target rotational speed set corresponding to an elapsed time from a reference position set above, an elapsed time calculation unit that counts the elapsed time; and A blade position calculation unit that calculates the current position of the wiper blade, and a blade position determination that compares the target position of the wiper blade corresponding to the elapsed time and the current position of the wiper blade calculated by the blade position calculation unit A motor rotational speed determination unit that compares a target rotational speed of the electric motor corresponding to the elapsed time and a current rotational speed of the electric motor; Based on the determination results of the position determination unit and the motor rotation number determination unit, the motor rotation number correction unit for correcting the rotation number of the electric motor, and the operation of the electric motor based on the instruction of the motor rotation number correction unit possess a drive control instruction unit for controlling the said motor speed correction unit, when the wiper blade does not reach the target position set in correspondence with the elapsed time, is set in advance in the target rotational speed When the correction target rotation speed obtained by adding the correction value is set, and the correction target rotation speed is larger than the upper limit rotation speed obtained by adding the correction addition upper limit value set in advance corresponding to the elapsed time to the target rotation speed Setting the upper limit rotational speed as the final target rotational speed for actually driving the electric motor and instructing the drive control instructing unit, and when the corrected target rotational speed is equal to or lower than the upper limit rotational speed, Set the correction target rotation speed as a final target speed, wherein the instructing the drive control instruction unit.

  In the present invention, a motor rotation speed correction unit that corrects the rotation speed of the electric motor based on the blade position and the motor rotation speed is provided, and the correction target rotation speed is suppressed while suppressing variations in the wiping cycle by correcting the motor rotation speed. Is appropriately suppressed. This causes a delay in the operation of the wiper blade, and even when the motor rotation speed is increased to recover it, the motor rotation speed in the vicinity of the reversing position does not become excessive, and the blade speed during reversal is suppressed and overrun. The occurrence of runs can be suppressed.

In the wiper control apparatus, the reference position of the elapsed time may be a lower reversal position of the wiper blade.

  According to the wiper control method of the present invention, for example, when a delay occurs in the operation of the wiper blade, the electric motor is driven and controlled based on the corrected target rotational speed, and the corrected target rotational speed is larger than the upper limit rotational speed. Since the upper limit rotational speed is set as the final target rotational speed, the increase in the motor rotational speed can be suppressed, and the blade speed during reversal can be suppressed. For this reason, even when the operation of the wiper blade is delayed and the motor rotational speed is increased to recover it, the motor rotational speed in the vicinity of the reverse position does not become excessive, and variations in the wiping cycle are caused by correcting the motor rotational speed. It is possible to suppress overrun of the blade at the reversal position while suppressing.

  According to the wiper control device of the present invention, since the motor rotation speed correction unit that corrects the rotation speed of the electric motor based on the blade position and the motor rotation speed is provided, variation in the wiping cycle is suppressed by correcting the motor rotation speed. Thus, the correction target rotational speed can be appropriately suppressed. For this reason, even when the operation of the wiper blade is delayed and the motor rotation speed is increased to recover it, the motor rotation speed in the vicinity of the reversal position does not become excessive, and the variation in the wiping cycle is suppressed and the reversal position is reduced. It is possible to suppress the overrun of the blade.

It is explanatory drawing which shows the whole structure of the wiper apparatus driven by the control method and control apparatus which is one Example of this invention. It is a block diagram which shows the structure of the control system of the wiper control apparatus by this invention. It is a flowchart which shows the process sequence of the wiper control method by this invention. It is explanatory drawing which shows the control state of the motor at the time of employ | adopting a control form like FIG.

  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 device driven by a control method / control device according to an embodiment of the present invention. The wiper device shown in FIG. 1 has a wiper arm 1a on the driver's seat side and a wiper arm 1b on the passenger seat side that are swingably provided on the vehicle body. A wiper blade 2a on the driver's seat side and a wiper blade 2b on the passenger seat side are attached to each wiper arm 1a, 1b. The wiper blades 2a and 2b (hereinafter abbreviated as blades 2a and 2b) are elastically in contact with the windshield 3 by spring members (not shown) incorporated in the wiper arms 1a and 1b. The vehicle body is provided with two wiper shafts 4a and 4b, and the wiper arms 1a and 1b are respectively attached to the wiper shafts 4a and 4b at the base ends thereof. Note that “a, b” in the reference numerals indicates members and portions related to the driver's seat side and the passenger seat side, respectively.

  In order to swing the wiper arms 1a and 1b, the wiper device is provided with two electric motors 7a and 7b (hereinafter abbreviated as motors 7a and 7b). The motors 7a and 7b are constituted by a motor body 8 and a speed reduction mechanism 9, and are driven and controlled by wiper control devices 10a and 10b. A wiper control device 10a that drives and controls the motor 7a is connected to an ECU 11 that is a vehicle-side controller via an in-vehicle LAN 12. Switch information such as ON / OFF of a wiper switch, Lo, Hi, INT (intermittent operation), engine start information, and the like are input to the wiper control device 10a from the ECU 11 via the LAN 12. The wiper control devices 10a and 10b are connected by a communication line 13.

  In the wiper device of FIG. 1, the motors 7a and 7b are feedback-controlled based on the elapsed time from the absolute position which is a control reference, and the positions of the blades 2a and 2b are controlled. Here, the lower inversion position is used as an absolute position, and the target rotational speed TR of the motors 7a and 7b at that time is set in advance by a map or the like corresponding to the elapsed time t from the lower inversion position. The wiper control devices 10a and 10b measure the elapsed time t from the lower reverse position, grasp the current rotational speed of the motors 7a and 7b, and compare it with the target rotational speed TR at the elapsed time. Then, depending on the difference between the target rotational speed TR and the current rotational speed, the motors 7a and 7b are appropriately controlled to control the operations of the blades 2a and 2b.

  In order to perform such feedback control, the motors 7a and 7b are provided with sensors for blade position detection. That is, the motors 7a and 7b are provided with a sensor that outputs a relative position signal indicating the movement amount of the blades 2a and 2b in proportion to the motor rotation angle, and a sensor that outputs an absolute position signal indicating a specific blade position. Yes. The relative position signal is a pulse signal (motor pulse) 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 generated when the blades 2a and 2b come to the control reference position (here, the lower reverse position).

  In this case, since the rotational speeds of the motors 7a and 7b and the rotational speeds of the wiper shafts 4a and 4b are in a fixed relationship based on the reduction ratio of the speed reduction mechanism 9, the rotational angles of the wiper shafts 4a and 4b are calculated based on the number of pulses. be able to. Further, the rotation angle of the wiper shafts 4a and 4b and the movement angle of the blades 2a and 2b have a certain correlation. Therefore, the movement angle of the blades 2a and 2b can be known by integrating the number of pulses of the relative position signal. Accordingly, the wiper control devices 10a and 10b detect the current positions of the blades 2a and 2b based on a combination of the absolute position signal indicating the lower inversion position and the number of pulses. Further, the wiper control devices 10a and 10b detect the current motor rotation speed by counting the motor pulses. Note that the rotation speed can also be calculated by the amount of change in the sensor output voltage with respect to the elapsed time.

  On the other hand, the wiper control devices 10a and 10b measure the elapsed time t from the time when the absolute position signal is obtained, and the target positions of the blades 2a and 2b and the target rotational speeds of the motors 7a and 7b at the current elapsed time. Obtain TR. Then, the current position of the blades 2a and 2b is compared with the target position to grasp the current state of the blade (delay and progress with respect to the target position), and the state of the rotational speed of the motors 7a and 7b (relative to the target rotational speed TR). The number of rotations of the motors 7a and 7b is calculated based on the height and the operation is controlled. That is, in the wiper device, the target value of the blade position and the motor rotation speed is set in advance using the elapsed time t as a parameter, and the motors 7a and 7b are feedback-controlled by comparing these target values with the current values.

  Such control information is exchanged between the wiper control devices 10a and 10b via the communication line 13, and the motors 7a and 7b are synchronously controlled based on the positional relationship between the blades. That is, the wiper control devices 10a and 10b first perform forward / reverse control of the motors 7a and 7b based on the blade position on its own side. At the same time, the wiper control devices 10a and 10b control the motors 7a and 7b based on the blade position information of both blades 2a and 2b, and control the wiper devices so that the blades do not interfere with each other and the angle difference does not increase. To do.

  As a result, the blades 2a and 2b swing between the lower inversion position A and the upper inversion position B, that is, in the wiping range 5 indicated by the alternate long and short dash line in the drawing, and rain and snow attached to the windshield 3 are wiped off. The At this time, since the blades 2a and 2b are driven and controlled using the elapsed time t as a parameter, variation in the wiping cycle between the upside down positions can be suppressed. The blades 2a and 2b are moved to the storage position C located below the lower inversion position A and stored in the storage unit 6 when the wiper is stopped. The storage unit 6 is provided inside a hood of a vehicle body (not shown). When the blades 2 a and 2 b are stored in the storage unit 6, the blades 2 a and 2 b retreat to the lowermost end of the windshield 3.

  On the other hand, in the wiper apparatus of FIG. 1, when the snow falls or when the battery voltage is lowered, the wiper operation speed is greatly reduced, and a large operation delay may occur in the first half of the one-way wiping operation. As described above, when such a delay occurs, the motor output is increased in the second half of the operation in order to recover the delay, but as a result, the blade speed becomes too high and the blade may overrun the reversal position. There is.

  Therefore, in the wiper device, in order to prevent overrun at the reversal position, an upper limit is set on the motor rotation speed to suppress an increase in blade speed when the operation is delayed. FIG. 2 is a block diagram showing the configuration of the control system of the wiper control device 10 according to the present invention. FIG. 3 is a flowchart showing the processing procedure of the wiper control method according to the present invention. The processing of FIG. 3 is executed by the wiper control devices 10a and 10b.

  As shown in FIG. 2, the wiper control devices 10a and 10b are provided with CPUs 21a and 21b and data transmission / reception units 22a and 22b. The wiper control device 10a is connected to the ECU 11 via the LAN 12. The wiper switch setting state (operation mode setting such as ON / OFF, Lo, Hi, and INT) from the ECU 11 and various vehicle information such as an engine start signal. Is entered. The wiper control devices 10a and 10b are further provided with ROMs 23a and 23b for storing control programs and various control information, and RAMs 24a and 24b for storing control data such as motor rotation speed and blade current position. ing. In addition, the wiper control devices 10a and 10b are provided with timers 25a and 25b for measuring the elapsed time t from the lower inversion position.

  The CPUs 21a and 21b are central processing units. Here, the CPU 21a connected to the ECU 11 is the master side, and the CPU 21b is the slave side. The CPUs 21a and 21b are connected to the communication line 13 via the data transmitting / receiving units 22a and 22b, and exchange position information and operation instructions with each other through them. The CPU 21a on the master side controls the operation of the motor 7a based on the position information of the blade 2b sent from the wiper control device 10b and the position information of itself (blade 2a) according to the state of the wiper switch. The CPU 21b on the slave side controls the operation of the motor 7b based on the position information of the blade 2a and the position information of itself (blade 2b) sent from the wiper control device 10a in accordance with the instruction from the wiper control device 10a.

  The CPUs 21a and 21b use timers 25a and 25b, respectively, to calculate elapsed time calculation units 26a and 26b that measure the elapsed time t from the absolute position signal, and the blades 2a and 2b based on the absolute position signal and the relative position signal. Blade position calculation units 27a and 27b for calculating the current position are provided. Further, the CPUs 21a and 21b read the target positions of the blades 2a and 2b corresponding to the elapsed time t calculated by the elapsed time calculation units 26a and 26b from the ROMs 23a and 23b, and read them into the blade position calculation units 27a and 27b. The blade position determination units 28a and 28b for comparing the current positions of the blades 2a and 2b calculated in the above and the target rotational speed TR of the motors 7a and 7b corresponding to the elapsed time t are read from the ROMs 23a and 23b, and the relative positions are read. Motor rotation speed determination units 29a and 29b are provided for comparing the current rotation speeds of the motors 7a and 7b calculated using the signals.

  The CPUs 21a and 21b further rotate the motors 7a and 7b based on the determination results in the blade position determination units 28a and 28b and the motor rotation number determination units 29a and 29, the positional relationship with the counterpart blade, wiper switch information, and the like. Motor rotation number correction units 31a and 31b for correcting the number are provided. The motor rotation speed correction units 31a and 31b determine the rotation speeds of the motors 7a and 7b in consideration of the above-described conditions. In the wiper device, the rotation speeds are the motors 7a and 7b acquired from the ROMs 23a and 23b. It is regulated by the upper limit value. In addition, the CPUs 21a and 21b are instructed to the motors 7a and 7b with respect to the rotation direction, duty, etc. based on the instructions of the motor rotation speed correction units 31a and 31b, and the blades 2a and 2b are appropriately operated between the upside down positions. Drive control instruction units 32a and 32b are provided.

  In the wiper device according to the present invention having such a configuration, the following processing is performed during the wiping operation. As shown in FIG. 3, first, at step S1, the elapsed time t from the lower inversion position is first grasped, and at step S2, the target rotational speed TR of the motors 7a, 7b corresponding to this elapsed time t is motor rotation. It is acquired by the number determination units 29a and 29b. The target rotational speed TR is stored in the ROMs 23a and 23b as described above, and is set in advance using the elapsed time t from the lower inversion position as a parameter. Accordingly, the target value of the motor speed, that is, the target value of the moving speed of the blades 2a and 2b is set in accordance with the position (angle) from the lower reverse position.

  After acquiring the motor target rotational speed TR, the process proceeds to step S3, and the current positions of the blades 2a and 2b are grasped. The current positions of the blades 2a and 2b are calculated by a combination of the absolute position signal indicating the lower inversion position and the pulse number of the relative position signal, and stored in the RAMs 24a and 24b. In addition to the current blade position, the current rotational speed of the motors 7a and 7b is also calculated in step S4. The motor rotation speed is calculated from the pulse count of the relative position signal, and is also stored in the RAMs 24a and 24b.

  After obtaining the current position of the blades 2a and 2b and the current rotation speed of the motors 7a and 7b, the process proceeds to step S5, and the current state of the blade (lags behind the target) from the elapsed time t and the blade position of the partner and the other side. The blade position determination unit 28a, 28b determines whether or not the user is moving forward, whether the relationship with the opponent is normal, or the like. Then, the process proceeds to step S6 and the subsequent steps, and the motor rotation speed correction units 31a and 31b appropriately correct the motor rotation speed based on the current state of the blade, the current rotation speed of the motors 7a and 7b, and the target rotation speed TR. .

  Here, first, in step S6, a correction value CN of the motor rotational speed is calculated. The “correction value CN” at this time is the current state of the blade ascertained by comparing the “blade target position” and the “blade current position” with respect to the elapsed time t, and the “motor target rotational speed TR” and “ It is calculated | required from the relationship with "the motor present rotation speed", and is calculated by the map etc. which were stored in RAM24a, 24b. After calculating the rotation speed correction value CN, the process proceeds to step S7, and the correction target rotation speed CTR is set from the correction value CN and the target rotation speed TR of the elapsed time. In this case, if the blade is delayed or slower than the target rotational speed TR, the correction value CN becomes a positive value, and the corrected target rotational speed CTR is set higher than the normal control value (target rotational speed TR).

  After the correction target rotational speed CTR is set in S7, the process proceeds to step S8, and the correction addition upper limit value α is calculated. The correction addition upper limit value α is preset according to the elapsed time t (α (t)), and is the maximum value of the motor rotational speed that can be added at the time of the elapsed time t. If the increase in the number is suppressed within this range, the value is such that no overrun occurs at the time of blade reversal. The correction addition upper limit value α (t) is also stored in the RAMs 24a and 24b, and the motor rotation speed correction units 31a and 31b read the α value corresponding to the elapsed time t from the RAMs 24a and 24b in S8, and step S9. Proceed to

  In step S9, an upper limit rotational speed ULR obtained by adding the α value to the target rotational speed TR is calculated, and the upper limit rotational speed ULR is compared with the corrected target rotational speed CTR obtained in step S7. At this time, if the corrected target rotational speed CTR is equal to or lower than the upper limit rotational speed ULR (CTR ≦ ULR = TR + α (t)), the blade operates without causing an overrun problem. CTR is output as it is as the final target rotational speed FTR, and the routine is exited. On the other hand, when the corrected target rotational speed CTR is larger than the upper limit rotational speed ULR (CTR> ULR), an overrun may occur at the time of reversal, so the process proceeds to step S11 to suppress the motor rotational speed.

  In step S11, if the previous corrected target rotational speed CTR is output as the final target rotational speed FTR as it is, the blade may exceed the speed at the time of reversal. Therefore, the correction addition upper limit α (t) is added to the target rotational speed TR. Upper limit rotation speed ULR (= TR + α (t)) is set as final target rotation speed FTR. As a result, the addition value (α) of the motor rotation speed during the elapsed time is suppressed, and the blade speed during reversal is suppressed. Accordingly, it is possible to suppress overrun at the time of blade reversal while suppressing variations in the wiping cycle by correcting the rotational speed.

  FIG. 4 is an explanatory diagram showing the motor control state when the blade operation is delayed in the wiper device adopting the control mode as shown in FIG. 3, where the horizontal axis is the elapsed time t, and the vertical axis is the rotation speed. It has become. FIG. 4 shows the control state of the motor 7a, but the motor 7b is also in the same control state. As indicated by a broken line in FIG. 4, in the conventional control mode, the motor rotation speed is greatly increased to recover the delay in the first half of the operation. For this reason, the motor rotation speed in the vicinity of the reversal position becomes an excessive state, and the possibility of overrun is very high. On the other hand, in the control mode according to the present invention, as shown by the solid line in FIG. 4, the final target rotational speed FTR of the motor is the upper limit rotational speed obtained by adding α (t) to the target rotational speed TR (one-dot chain line). Lower than ULR (two-dot chain line). Therefore, the motor rotation speed in the vicinity of the reversing position does not become excessive as shown by the broken line, the blade speed during reversing is suppressed, and the occurrence of overrun is also suppressed.

  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, the example in which the present invention is applied to the wiper device that drives the left and right wiper arms 1a and 1b by individual motors has been described. However, the present invention is not limited to such a wiper device. The present invention can also be applied to a wiper device that operates the left and right wiper arms by a single motor and a link mechanism. In that case, only one wiper control device is sufficient, and it is possible to cope with only the configuration of the wiper control device 10a among the above-described wiper control devices 10a and 10b. In this case, the data transmission / reception unit 22a becomes unnecessary. Further, the present invention is applicable not only to a parallel wiping type (tandem type) wiper apparatus as shown in FIG. 1 but also to an opposing wiping type (opposite type) wiper apparatus.

DESCRIPTION OF SYMBOLS 1a, 1b Wiper arm 2a, 2b Wiper blade 3 Windshield 4a, 4b Wiper shaft 5 Wiping range 6 Storage part 7a, 7b Motor 8 Motor main body 9 Deceleration mechanism 10a, 10b Wiper control apparatus 11 ECU
12 In-vehicle LAN
13 Communication lines 21a, 21b CPU
22a, 22b Data transceiver 23a, 23b ROM
24a, 24b RAM
25a, 25b Timers 26a, 26b Elapsed time calculation units 27a, 27b Blade position calculation units 28a, 28b Blade position determination units 29a, 29b Motor rotation number determination units 31a, 31b Motor rotation number correction units 32a, 32b Drive control instruction unit A Lower Reverse position B Upper reverse position C Storage position t Elapsed time CN Correction value TR Motor target rotation speed CTR Correction target rotation speed α Correction addition upper limit value ULR Upper limit rotation speed FTR Final target rotation speed

Claims (4)

A wiper blade disposed on the wiping surface; and an electric motor for reciprocating the wiper blade on the wiping surface, wherein the electric motor has elapsed from a reference position set on the wiping region. A control method for a wiper device that is driven and controlled based on a target rotational speed set corresponding to time,
The electric motor is driven based on a corrected target rotational speed obtained by adding a preset correction value to the target rotational speed when the wiper blade has not reached the target position set corresponding to the elapsed time. And
When the corrected target rotational speed is larger than an upper limit rotational speed obtained by adding a correction addition upper limit value set in advance corresponding to the elapsed time to the target rotational speed, as a final target rotational speed for actually driving the electric motor The wiper control method is characterized in that the upper limit rotational speed is set, and the corrected target rotational speed is set as the final target rotational speed when the corrected target rotational speed is less than or equal to the upper limit rotational speed. The wiper control method according to claim 1 , wherein the reference position of the elapsed time is a lower reversal position of the wiper blade . A wiper blade disposed on the wiping surface; and an electric motor for reciprocating the wiper blade on the wiping surface, wherein the electric motor has elapsed from a reference position set on the wiping region. A control device for a wiper device that is driven and controlled based on a target rotational speed set corresponding to time,
An elapsed time calculation unit for measuring the elapsed time;
A blade position calculation unit for calculating a current position of the wiper blade;
A blade position determination unit that compares a target position of the wiper blade corresponding to the elapsed time and a current position of the wiper blade calculated by the blade position calculation unit;
A motor rotational speed determination unit that compares a target rotational speed of the electric motor corresponding to the elapsed time and a current rotational speed of the electric motor;
A motor rotation number correction unit that corrects the rotation number of the electric motor based on the determination results in the blade position determination unit and the motor rotation number determination unit;
Have a, a drive control instruction unit for controlling the operation of the electric motor based on an instruction of the motor speed compensation unit,
The motor rotation speed correction unit is
If the wiper blade has not reached the target position set corresponding to the elapsed time, set a corrected target rotational speed obtained by adding a preset correction value to the target rotational speed,
When the corrected target rotational speed is larger than an upper limit rotational speed obtained by adding a correction addition upper limit value set in advance corresponding to the elapsed time to the target rotational speed, as a final target rotational speed for actually driving the electric motor The upper limit rotational speed is set and instructed to the drive control instruction section. When the corrected target rotational speed is equal to or lower than the upper limit rotational speed, the corrected target rotational speed is set as the final target rotational speed and the drive control instruction is performed. A wiper control device characterized by instructing a unit. 4. The wiper control device according to claim 3 , wherein the reference position of the elapsed time is a lower reversal position of the wiper blade .

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