JP2020044881A - Wiper device - Google Patents

Abstract

To provide a wiper device which reduces discomfort given to a user when actuating the wiper device while suppressing heat generation rise of a motor.SOLUTION: A wiper device includes wiper blades 2a, 2b which are connected with wiper arms 1a, 1b reciprocating and oscillating on a glass surface and wipe the glass surface of a vehicle, motors 6a, 6b which cause the wiper arms 1a, 1b to reciprocate and oscillate, and wiper control devices 10a, 10b which control the motors 6a, 6b. The wiper control devices 10a, 10b include a motor load detection part which detects load state of the motors 6a, 6b and a motor temperature detection part which detects temperatures of the motors 6a, 6b. When the load state of the motors 6a, 6b exceeds a prescribed state, a wiping speed of the wiper blades 2a, 2b is changed so as to get to slow and, when the temperature of the motors 6a, 6b exceeds the prescribed temperature, the wiper blades 2a, 2b are changed into an intermittent wiping motion.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a wiper device.

  BACKGROUND ART A vehicle such as an automobile is provided with a wiper device for wiping rain adhered to a windshield (a windshield) and splashes from a preceding vehicle in order to secure a driver's view in rainy weather or the like. The wiper device has a wiper arm that is swingably controlled by a wiper control device, and a wiper blade that is in contact with a windshield is attached to a tip of the wiper arm. The wiper arm swings by changing the rotational motion of the motor into a reciprocating motion by a link mechanism to perform a reciprocating swing. When the wiper arm swings back and forth, the wiper blade performs a wiping operation on the windshield.

  In this wiper device, a high load may be applied to the motor due to a frictional force between the wiper blade and the windshield. Conventionally, there is a wiper device that detects a load applied to a motor and, when the load applied to the motor increases, reduces the speed of the wiping operation of the wiper blade and continues the wiping operation while suppressing an increase in heat generation of the motor ( For example, see Patent Document 1). In this wiper device, if the load on the motor is not sufficiently reduced even when the speed of the wiping operation is reduced, the wiping operation is changed to the intermittent wiping operation, the wiping frequency is reduced, and the increase in the heat generation of the motor is suppressed. I have.

Japanese Patent No. 5130303

  However, in the above-described conventional wiper device, a high load is applied to the motor, and even if the speed of the wiping operation is reduced, the load applied to the motor may not be sufficiently reduced. In this case, after the speed is reduced in the continuous wiping operation, the operation is immediately changed to the intermittent wiping operation. Therefore, since the movement of the wiper blade changes rapidly from the continuous wiping operation in which the wiping speed is not reduced to the intermittent wiping operation, the user may feel uncomfortable.

  The problem to be solved by the present invention is to provide a wiper device that reduces a sense of discomfort given to a user when operating the wiper device while suppressing an increase in heat generation of a motor.

  One aspect of the present invention is to control a wiper blade for wiping a glass surface of a vehicle, a wiper arm connected to the wiper blade and reciprocatingly swinging on the glass surface, a wiper motor for reciprocatingly swinging the wiper arm, and controlling the wiper motor. A wiper device comprising: a load detector that detects a load state of the wiper motor; and a temperature detector that detects a temperature of the wiper motor; When the load state of the wiper motor detected by the section exceeds a predetermined state, the wiping speed of the wiper blade is changed to be slow, and the temperature of the wiper motor detected by the temperature detection section exceeds a predetermined temperature. A wiper control device for changing the wiper blade to an intermittent wiping operation.

  One embodiment of the present invention is the above-described wiper control device, wherein the control device is configured such that a vehicle speed detected by the vehicle speed detection unit is low, and a temperature of the wiper motor detected by the temperature detection unit. When the temperature exceeds a predetermined temperature, the wiper blade is changed to an intermittent wiping operation.

  ADVANTAGE OF THE INVENTION According to this invention, when operating a wiper apparatus, suppressing an increase in heat generation of a motor, the discomfort given to a user can be reduced.

It is a figure showing an example of the schematic structure of the wiper device in this embodiment. FIG. 2 is a block diagram illustrating an example of a configuration of a control system of the wiper control device illustrated in FIG. 1. 6 is a flowchart illustrating an example of an operation of the wiper control device. 5 is a graph illustrating an example of a change over time of a wiping speed of a wiper blade.

  Hereinafter, the present invention will be described through embodiments of the present invention, but the following embodiments do not limit the invention according to the claims. Further, not all combinations of the features described in the embodiments are necessarily indispensable to the solution of the invention. In the drawings, the same or similar portions are denoted by the same reference numerals, and redundant description may be omitted. In addition, shapes and sizes of elements in the drawings may be exaggerated for clearer description. Hereinafter, a wiper device according to an embodiment will be described with reference to the drawings.

  FIG. 1 is a diagram illustrating an example of a schematic configuration of a wiper device according to the present embodiment. As shown in FIG. 1, the wiper device includes a driver seat-side wiper arm 1a and a passenger seat-side wiper arm 1b that are swingably provided on a vehicle body. A wiper blade 2a on the driver's seat side and a wiper blade 2b on the passenger's seat side are attached to each of the wiper arms 1a and 1b. The wiper blades 2a and 2b are in elastic contact with the glass surface of the windshield 3 by a spring member or the like (not shown) provided inside the wiper arms 1a and 1b, respectively.

  The vehicle body is provided with two wiper shafts (pivot shafts) 4a and 4b, and the wiper arms 1a and 1b are attached to the wiper shafts 4a and 4b at their base ends. Note that “a, b” in the reference numerals indicates members and parts related to the driver's seat side and the passenger seat side, respectively.

  In order to swing the wiper arms 1a and 1b back and forth on the glass surface of the windshield 3, the system is provided with two electric motors (wiper motors, hereinafter abbreviated as "motors 6a and 6b") that are PWM duty controlled. ing. The motors 6a and 6b are composed of a motor body 7 and a speed reduction mechanism 8, and are driven and controlled by the wiper control devices 10a and 10b to rotate forward and backward. The wiper control device 10a that drives and controls the motor 6a is connected to an ECU (Electronic Control Unit) 11 that is a vehicle-side controller via an in-vehicle LAN 12. The wiper control devices 10a and 10b are connected by a communication line 13.

  For the wiper control device 10a, switch information such as ON / OFF of a wiper switch, Hi and Lo, and engine start information (an engine start signal supplied when an ignition switch for starting the vehicle engine is turned on, A signal indicating the vehicle speed) is input from the ECU 11 via the LAN 12.

  In the wiper device shown in FIG. 1, feedback control (PI control) of the motors 6a and 6b is performed based on position information of the wiper blades 2a and 2b. Here, the target speeds of the wiper blades are set in accordance with the positions of the wiper blades 2a and 2b, and are stored in advance in the wiper control devices 10a and 10b in the form of a map or the like.

  The wiper control devices 10a and 10b detect the current positions of the wiper blades 2a and 2b, and detect the moving speeds of the wiper blades 2a and 2b from the rotational speeds of the wiper shafts 4a and 4b. Then, the current speed of the wiper blades 2a, 2b is compared with the target speed of the wiper blades 2a, 2b at the position, and the motors 6a, 6b are appropriately controlled according to the difference between the target speed and the current speed. .

  A temperature sensor 14 and a vehicle speed sensor (vehicle speed detecting unit) 15 are connected to the ECU 11. Temperature sensor 14 detects the temperature of motor 6a. The temperature sensor 14 transmits the detected temperature of the motor 6a to the ECU 11. The vehicle speed sensor 15 detects the wheel speed of the vehicle and calculates the vehicle speed by performing an operation on the wheel speed. The vehicle speed sensor 15 transmits the calculated vehicle speed to the ECU 11. The ECU 11 performs control based on the temperature of the motor 6 a transmitted from the temperature sensor 14 and the vehicle speed transmitted from the vehicle speed sensor 15. The ECU 11 transmits the transmitted temperature and the vehicle speed of the motor 6a to the wiper control device 10a as a motor temperature signal and a vehicle speed signal, respectively.

  FIG. 2 is a block diagram showing an example of a configuration of a control system of the wiper control device shown in FIG. Since the wiper control devices 10a and 10b have the same configuration, only the wiper control device 10a will be described in FIG. 2 and the following description.

  As shown in FIG. 2, the wiper control device 10a includes a motor drive unit 20, a CPU 21, and a data transmission / reception unit 22. The wiper control device 10a is connected to the ECU 11 via the LAN 12.

  The wiper control device 10a further includes a ROM 23 in which a control program and various types of control information are stored, and a RAM 24 in which control data such as the motor rotation speed and the current position of the wiper blade are stored. The RAM 24 stores a load reference value, a motor temperature threshold value, and a vehicle speed threshold value. The load reference value, the motor temperature threshold value, and the vehicle speed threshold value are all values used in the operation of the wiper control device 10a shown in FIG. The load reference value is a reference value for determining that the load on the motor 6a is high, and the motor temperature threshold value is a threshold value for determining that the temperature of the motor 6a is high. The threshold value is a threshold value for determining that the vehicle speed is low (for example, 60 km / h). The load reference value, the motor temperature threshold value, and the vehicle speed threshold value can be appropriately set.

  The CPU 21 is a central processing unit. Here, the CPU 21 connected to the ECU 11 is on the master side, and the CPU of the wiper control device 10b not shown in FIG. 2 is on the slave side. The CPU 21 of the wiper control device 10a is connected to the CPU of the wiper control device 10b via the data transmission / reception unit 22 and the communication line 13. The CPU 21 of the wiper control device 10a and the CPU of the wiper control device 10b exchange positional information and operation instructions through the communication line 13. The CPU 21 on the master side controls the operation of the motor 6a based on the position information of the wiper blade 2b sent from the wiper control device 10b and the position information of itself (wiper blade 2a) according to the state of the wiper switch. The CPU on the slave side controls the operation of the motor 6b based on the position information of the wiper blade 2a or the position information of the wiper blade 2b (wiper blade 2b) sent from the wiper control device 10a in accordance with an instruction from the wiper control device 10a. .

  The motor drive unit 20 includes a driver and an inverter circuit. When a control signal (Duty) output from the CPU 21 of the wiper control device 10a is input, the driver outputs, for example, four switching signals to the inverter circuit based on the control signal. The inverter circuit includes four N-channel MOSFETs (field-effect transistors, hereinafter abbreviated as “MOSFETs”) as switch elements for controlling power supply to the motor 6a. Four switching signals output from the driver are input to each gate terminal of the MOSFET. The inverter circuit is configured by connecting a series circuit C1 in which a pair of MOSFETs (referred to as MOSFET 1u and MOSFET 1d) are connected in series and a series circuit C2 in which a pair of MOSFETs (referred to as MOSFET 2u and MOSFET 2d) are connected in series. Have been.

  The source terminal of the MOSFET 1u and the drain terminal of the MOSFET 1d are connected to a common connection point N1. The source terminal of the MOSFET 2u and the drain terminal of the MOSFET 2d are connected to a common connection point N2. The drain terminal of the MOSFET 1u and the drain terminal of the MOSFET 2u are connected to the power supply of the inverter circuit. The source terminal of the MOSFET 1d and the source terminal of the MOSFET 2d are grounded. With the above configuration, the inverter circuit is configured as an H-bridge circuit.

  The motor 6a is configured as a motor including a first electrode connected to the common connection point N1 of the inverter circuit and a second electrode connected to the common connection point N2 of the inverter circuit. Each of the MOSFETs 1u, 1d, 2u, and 2d is turned off when an L (low) level switching signal is input to the gate terminal, and no current flows from the drain terminal to the source terminal. On the other hand, each of the MOSFETs 1u, 1d, 2u, and 2d is turned on when an H (high) level switching signal is input to the gate terminal, and current flows from the drain terminal to the source terminal.

  In the motor 6a, when the MOSFET 1u and the MOSFET 2d are turned on, a current flows from the first electrode to the second electrode, and the wiper shaft 4a rotates in one direction. On the other hand, in the motor 6a, when the MOSFET 1d and the MOSFET 2u are turned on, a current flows from the second electrode to the first electrode, and the wiper shaft 4a rotates in the other direction. The CPU 21 of the wiper control device 10a controls the rotation of the motor 6a via a driver to cause the wiper blade 2a to perform a reciprocating wiping operation.

  The wiper control device 10a operates the motor 6a by the motor drive unit 20 so that the wiper blade 2a performs a continuous wiping operation or an intermittent wiping operation. The continuous wiping operation is a wiping operation performed when the motor 6a is operated almost without stopping when the wiper blade 2a is turned back, and the intermittent wiping operation is performed when the motor 6a is turned over for a certain time when the wiper blade 2a is turned back. For example, the wiping operation is performed by stopping the operation for 0.5 s to 1 s and restarting the operation. The wiper control device 10a causes the wiper blade 2a to perform a continuous wiping operation or an intermittent wiping operation based on an instruction from the drive control instruction unit 29.

  The CPU 21 includes a blade speed detection unit 25, a motor load detection unit 26, a motor temperature detection unit (temperature detection unit) 27, a vehicle speed / speed determination unit 28, and a drive control instruction unit 29. The blade speed detector 25 detects the current moving speed (current speed) of the wiper blade 2a based on a sensor signal from a sensor magnet (not shown) mounted on the motor 6a. The blade speed detector 25 outputs the detected wiping speed, which is the current moving speed of the wiper blade 2a, to the drive control instruction unit 29 as a wiping speed signal.

  The motor load detection unit 26 detects a load applied to the motor 6a via the wiper blade 2a based on a motor speed (motor pulse) of the motor 6a and a PWM control signal output from the CPU 21 to the motor drive unit 20. The motor load detection unit 26 outputs the detected load (load state) applied to the motor 6a to the drive control instruction unit 29 as a motor load signal.

  The motor temperature detector 27 compares the temperature of the motor 6 a based on the motor temperature signal transmitted from the ECU 11 with the motor temperature threshold stored in the RAM 24. The motor temperature detector 27 determines whether the motor 6a is at a high temperature as a result of the comparison. When the temperature of the motor 6a based on the motor temperature signal exceeds the motor temperature threshold value (when the temperature exceeds a predetermined temperature), the motor temperature detection unit 27 determines that the motor 6a is at a high temperature. , And outputs a motor high temperature signal to the drive control instructing section 29.

  The vehicle speed determination unit 28 compares the vehicle speed based on the vehicle speed signal transmitted from the ECU 11 with the vehicle speed threshold stored in the RAM 24. The vehicle speed determining unit 28 determines whether the vehicle speed is low as a result of the comparison. When the vehicle speed based on the vehicle speed signal is equal to or less than the vehicle speed threshold and the vehicle speed is determined to be low, the vehicle speed determination unit 28 outputs a low vehicle speed signal to the drive control instruction unit 29.

  The drive control instructing unit 29 includes a wiping speed of the wiper blade 2a based on the wiping speed signal output from the blade speed detecting unit 25, a load applied to the motor 6a based on the motor load signal output from the motor load detecting unit 26, and a motor temperature. A drive signal for the motor 6a is generated based on a motor high temperature signal output from the detection unit 27, a low vehicle speed signal output from the vehicle speed / speed determination unit 28, and the like. The drive control instruction unit 29 controls the drive of the motor 6a by outputting the generated drive signal to the motor drive unit 20. The drive control instructing unit 29 can set the wiping speed in the continuous wiping operation in two stages of “high speed” and “normal”, and can set the wiping speed in three stages by adding the intermittent wiping operation. is there. The wiper switch is provided with a “Hi switch” and a “Lo switch”, and the drive control instruction unit 29 controls the wiping speed at a high speed when the “Hi switch” is turned on. When turned on, the wiping speed is controlled normally. The drive control instructing unit 29 may be configured to set the wiping speed of the wiper blade 2a to four or more steps, or may be set to stepless at a speed lower than “high speed” depending on the detection state of the raindrop sensor by the auto board. You may do so. Although the wiping speed during the intermittent wiping operation is constant, the wiping speed during the intermittent wiping operation may be set in a plurality of stages.

  Next, the operation of the wiper control device 10a will be described. FIG. 3 is a flowchart illustrating an example of the operation of the wiper control device 10a. As shown in FIG. 3, the wiper control device 10a starts control when switch information indicating ON of a Lo switch among the wiper switches is input when the wiper switch is not operated. First, the wiper control device 10a controls the motor 6a so that the wiping speed of the wiper blade 2a is normal (normal speed) (step S11). When switch information indicating a Hi switch among the wiper switches is input, the wiper control device 10a controls the motor 6a so that the wiping speed of the wiper blade 2a is high (high speed). The subsequent control is common to the control after step S11.

  Next, the wiper control device 10a determines whether the load applied to the motor 6a is high based on the motor load signal output by the motor load detection unit 26 in the drive control instruction unit 29 (Step S12). For example, when the load applied to the motor 6a exceeds the load reference value (exceeds a predetermined state), the drive control instruction unit 29 determines that the load applied to the motor 6a is high. When it is determined that the load applied to the motor 6a is not high (step S12: NO), the drive control instruction unit 29 returns to step S11 and controls the motor 6a so that the wiping speed of the wiper blade 2a becomes the normal speed. . When the wiping speed is the normal speed, the drive control instruction unit 29 maintains the wiping speed.

  If it is determined that the load on the motor 6a is high (step S12: YES), the drive control instruction unit 29 reduces the wiping speed (step S13) and changes the wiping speed of the wiper blade 2a to a lower speed. When the wiping speed is reduced, the frictional force between the wiper blade 2a and the windshield 3 is reduced, and the load on the motor 6a is reduced. The drive control instruction unit 29 linearly decreases the wiping speed of the wiper blade 2a. The drive control instructing unit 29 may decrease the wiping speed stepwise.

  Subsequently, the wiper control device 10a uses the drive control instruction unit 29 to determine whether the load on the motor 6a is low (step S14). For example, when the load applied to the motor 6a is equal to or less than the load reference value, the drive control instruction unit 29 determines that the load applied to the motor 6a is low.

  If it is determined that the load on the motor 6a is low (step S14: YES), the drive control instruction unit 29 returns to step S11, and controls the motor 6a so that the wiping speed of the wiper blade 2a becomes the normal speed. When it is determined that the load on the motor 6a is not low (step S14: NO), the drive control instruction unit 29 determines whether the wiping speed of the wiper blade 2a is the minimum speed (step S15).

  When it is determined that the wiping speed of the wiper blade 2a is not the lowest speed (step S15: NO), the drive control instruction unit 29 returns to step S13, and decreases the wiping speed of the wiper blade 2a. When it is determined that the wiping speed of the wiper blade 2a is the lowest speed (Step S15: YES), the drive control instruction unit 29 controls the wiping speed to the lowest (Step S16).

  Subsequently, the drive control instruction unit 29 determines whether the load on the motor 6a is low (Step S17). The drive control instructing unit 29 determines that the load applied to the motor 6a is low, for example, when the load applied to the motor 6a is equal to or less than the load reference value, similarly to the determination in step S14.

  If it is determined in step S17 that the load applied to the motor 6a is low (step S17: YES), the drive control instructing unit 29 returns to step S11 and controls the motor 6a so that the wiping speed of the wiper blade 2a becomes the normal speed. Control. If it is determined that the load on the motor 6a is not low (step S17: NO), the drive control instructing unit 29 determines whether the vehicle speed is low (step S18). The drive control instructing unit 29 determines whether or not the vehicle speed is low based on whether or not the vehicle speed / speed determination unit 28 outputs a low vehicle speed signal.

  When the low vehicle speed signal is output by the vehicle speed determination unit 28 and it is determined that the vehicle speed is low (step S18: YES), the drive control instruction unit 29 determines whether the motor temperature is high. (Step S19). The drive control instruction unit 29 determines whether the motor temperature is high based on whether the motor high temperature signal is output from the motor temperature detection unit 27.

  When the motor temperature detection unit 27 outputs a motor high temperature signal and determines that the motor temperature is high (step S19: YES), the drive control instruction unit 29 changes the wiping speed of the wiper blade 2a from the continuous wiping operation. The drive of the motor 6a is controlled so as to change to the intermittent wiping operation (step S20). Even when the load on the motor 6a is large, when the temperature of the motor 6a is not high, the heat generation of the motor 6a does not progress so that there is little fear that the motor 6a will break down even if the continuous wiping operation is performed. However, when the temperature of the motor 6a is high, it is more necessary to prevent the failure of the motor 6a.

  Therefore, when the motor temperature detection unit 27 determines that the motor high temperature signal is not output and the motor temperature is not high (step S19: NO), the drive control instruction unit 29 returns to step S16, and the wiper The motor 6a is controlled so that the wiping speed of the blade 2a becomes the minimum speed. Thus, the continuous wiping operation is maintained without changing the wiping operation of the wiper blade 2a to the intermittent wiping operation. In step S18, when the vehicle speed / speed determining unit 28 does not output the low vehicle speed signal and determines that the vehicle speed is not low (step S18: NO), the drive control instruction unit 29 performs wiping of the wiper blade 2a. The motor 6a is controlled to change the operation from the continuous wiping operation to the intermittent wiping operation (step S20).

  Subsequently, the drive control instruction unit 29 determines whether the load on the motor 6a is low (Step S21). The drive control instructing unit 29 determines that the load applied to the motor 6a is low, for example, when the load applied to the motor 6a is equal to or less than the load reference value, similarly to the determination in step S14.

  If it is determined in step S21 that the load applied to the motor 6a is low (step S21: YES), the drive control instruction unit 29 returns to step S16, and controls the motor 6a so that the wiping speed of the wiper blade 2a becomes the minimum speed. Control. Thus, when the load on the motor 6a is reduced, the wiping operation of the wiper blade 2a is returned from the intermittent wiping operation to the continuous wiping operation. When it is determined that the load on the motor 6a is not low (step S21: NO), the drive control instruction unit 29 returns to step S20, and controls the motor 6a so that the wiper blade 2a continues the intermittent wiping operation. .

  An example of a temporal change in the wiping speed by the wiper control device 10a having the above configuration will be described. FIG. 4 is a graph showing an example of a temporal change of the wiping speed of the wiper blade. In FIG. 4, a curve LB shows an example of a time change of a load applied to the motor 6a, and a curve TB shows an example of a temperature change (change of the motor temperature) of the motor 6a. Also, the polygonal line WV shows an example of a temporal change in the wiping speed. FIG. 4 shows a load reference value Lth and a motor temperature threshold value Tth.

  As shown in FIG. 4, when the wiper blade 2a was operating at the normal wiping speed (normal speed), at time t1, the load on the motor 6a exceeded the load reference value Lth. In this case, the wiping speed starts to be reduced at time t1. Thereafter, for example, when the load applied to the motor 6a decreases and becomes equal to or less than the load reference value Lth, the wiping speed is returned to the normal speed.

  In the example shown in FIG. 4, even at time t1, the wiping speed is gradually reduced even if the wiping speed starts to be reduced because the load on the motor 6a is increasing. Thereafter, at time t2, the wiping speed becomes the minimum speed. After the time t2 when the wiping speed of the wiper blade 2a becomes the lowest speed, the wiper blade 2a operates at the lowest speed, but until the motor temperature of the motor 6a becomes high, the wiper blade 2a performs the continuous wiping operation at the lowest speed. To continue.

  In the example shown in FIG. 4, the motor temperature of the motor 6a has been gradually rising up to this point. Thereafter, at the time point t3 when the motor temperature of the motor 6a exceeds the motor temperature threshold value Tth, the wiper blade 2a performing the continuous wiping operation at the lowest speed starts the intermittent wiping operation.

  Therefore, the wiper blade 2a performs the continuous wiping operation at the normal wiping speed until time t1, and performs the continuous wiping operation from time t1 to time t2 while gradually decreasing the speed from the normal speed. Subsequently, from time t2 to time t3, the wiper blade 2a performs the continuous wiping operation at the minimum speed, and performs the intermittent wiping operation after time t3.

  As described above, in the above example, when the load applied to the motor 6a increases, when the wiper blade 2a performs the continuous wiping operation, the wiping speed is reduced, and after the wiping speed becomes the minimum speed. In other words, the wiper blade 2a performs a continuous wiping operation at the lowest speed. Further, while the wiper blade 2a performs the continuous wiping operation at the lowest speed, when the motor temperature of the motor 6a becomes high, the wiping operation of the wiper blade 2a is changed from the continuous wiping operation to the intermittent wiping operation.

  For example, when the motor temperature of the motor 6a is not considered, the wiping operation of the wiper blade 2a performing the continuous wiping operation at a relatively high speed such as a normal speed due to an increase in the load applied to the motor 6a, for example, suddenly at time t2 The operation may be changed to the intermittent wiping operation in the first place, giving the user a feeling of strangeness. In this regard, in the above example, since the wiping operation of the wiper blade 2a is changed to the intermittent wiping operation when the motor temperature of the motor 6a becomes high, for example, the wiper having the lowest wiping speed at the time t3. The wiping operation of the blade 2a is changed to an intermittent wiping operation. Therefore, even if the load on the motor 6a increases and the wiping speed of the wiper blade 2a decreases, it is possible to suppress a situation in which the continuous wiping operation of the wiper blade 2a at a relatively high speed is suddenly changed to the intermittent wiping operation. As a result, the sense of discomfort given to the user can be reduced.

  Further, in the above example, since it takes time until the wiping operation of the wiper blade 2a becomes the intermittent wiping operation, it can be expected that the user turns off the wiper switch to terminate the use of the wiper device. Further, the user often desires to use the wiping operation of the wiper blade 2a as a continuous wiping operation instead of the intermittent wiping operation as much as possible. In the above example, since it takes time until the wiping operation of the wiper blade 2a becomes the intermittent wiping operation, it is possible to meet such a user request.

  As a technique for reducing the load on the motor 6a, it is conceivable to provide a delay time until the wiping speed of the wiper blade 2a becomes the minimum speed and then change to the intermittent wiping operation, but when the motor temperature of the motor 6a is high, However, there is a problem that a failure of the motor 6a may be induced. Further, it is conceivable to provide a threshold value for the load on the motor 6a for changing the wiping operation of the wiper blade 2a to the intermittent wiping operation. However, the threshold value is set because the wiping speed of the wiper blade 2a decreases. There is a problem that becomes difficult. In this regard, in the above example, these problems can be prevented from occurring.

  In the above example, the wiping operation of the wiper blade 2a is changed to the intermittent wiping operation when the vehicle speed is low. For this reason, the change of the wiper blade 2a to the intermittent wiping operation during high-speed traveling can be suppressed. Therefore, it is possible to make it difficult to obstruct the driver's view during high-speed traveling.

  The wiper control device 10a in the above-described embodiment may be realized by a computer. In that case, a program for realizing this function may be recorded on a computer-readable recording medium, and the program recorded on this recording medium may be read and executed by a computer system. Here, the “computer system” includes an OS and hardware such as peripheral devices. The “computer-readable recording medium” refers to a portable medium such as a flexible disk, a magneto-optical disk, a ROM, and a CD-ROM, and a storage device such as a hard disk built in a computer system. Further, a "computer-readable recording medium" refers to a communication line for transmitting a program via a network such as the Internet or a communication line such as a telephone line, and dynamically holds the program for a short time. Such a program may include a program that holds a program for a certain period of time, such as a volatile memory in a computer system serving as a server or a client in that case. The program may be for realizing a part of the functions described above, or may be a program that can realize the functions described above in combination with a program already recorded in a computer system. It may be realized using a programmable logic device such as an FPGA (Field Programmable Gate Array).

  As described above, the embodiments of the present invention have been described in detail with reference to the drawings. However, the specific configuration is not limited to the embodiments, and includes a design and the like within a range not departing from the gist of the present invention. . For example, in the embodiment, a wiper device that includes two electric motors that are wiper motors and that wipes a wiper arm and a wiper blade (hereinafter, referred to as “wiper arm or the like”) on a driver side and a passenger side in substantially the same direction is provided. However, the present invention is not limited to this, and the two electric motors are arranged symmetrically with respect to the windshield 3 and the opposite wiping type in which the wiper arms and the like of the driver's seat side and the passenger's seat side are wiped so as to face each other. It can also be applied to the wiper device. Further, in the embodiment, the wiper device provided with two electric motors has been described. However, the configuration of the wiper device is not limited to this, and as shown in FIG. 1 of Japanese Patent Application Laid-Open No. 2005-94821, a link mechanism is provided. Alternatively, the wiper arm and the like on the driver's seat side and the passenger's seat side may be operated by one electric motor.

1a, 1b Wiper arms 2a, 2b Wiper blade 3 Windshields 6a, 6b Motors 10a, 10b Wiper control device 14 Temperature sensor 15 Vehicle speed sensor (vehicle speed detection unit)
20: motor drive unit 21: CPU
23… ROM
24 ... RAM
25: blade speed detecting section 26: motor load detecting section 27: motor temperature detecting section (temperature detecting section)
28: vehicle speed / speed judging unit 29: drive control instruction unit Lth: load reference value Tth: motor temperature threshold value

Claims (2)

A wiper blade for wiping the glass surface of the vehicle,
A wiper arm connected to the wiper blade and swinging back and forth on a glass surface;
A wiper motor that reciprocates the wiper arm,
A control device for controlling the wiper motor,
A wiper device comprising:
The control device includes:
A load detector that detects a load state of the wiper motor;
A temperature detector for detecting the temperature of the wiper motor,
With
When the load state of the wiper motor detected by the load detection unit exceeds a predetermined state, the wiping speed of the wiper blade is changed to a lower speed,
A wiper device, wherein the wiper blade is changed to an intermittent wiping operation when the temperature of the wiper motor detected by the temperature detector exceeds a predetermined temperature. A vehicle speed detecting unit that detects a speed of the vehicle,
The control device includes:
The method according to claim 1, wherein the wiper blade is changed to an intermittent wiping operation when the vehicle speed detected by the vehicle speed detection unit is low and the temperature of the wiper motor detected by the temperature detection unit exceeds a predetermined temperature. The wiper device as described.

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