JP2018127171A - Wiper device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wiper device that prevents washer liquid from being unnecessarily jetted in a case where a wiper motor malfunctions.SOLUTION: A microcomputer 58 determines that a wiper motor is malfunctioning in a case where a voltage of a battery is equal to or higher than an upper limit value or equal to or lower than a lower limit value, in a case where a current flowing in a coil of the wiper motor 18 is equal to or higher than an upper limit value or equal to or lower than a lower limit value, in a case where a temperature of a circuit board of a drive circuit 56 becomes equal to or higher than a predetermined value, or in a case where a rotation angle of an output shaft 32 detected by a rotation angle sensor 54 does not change although the wiper motor 18 has been electrically conducted. Thereby, control is exerted such that even if an actuation signal is input from a washer switch 62 via a vehicle ECU 90, the washer motor 64 is not actuated.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a wiper device.

  The windshield glass of a vehicle is cleaned with a washer liquid sprayed from a window washer device controlled in cooperation with a wiper blade wiping operation by the control of the wiper device. More specifically, the windshield glass is wiped with a wiper blade to clean the windshield glass and secure visibility from the passenger compartment. After spraying the washer liquid, it is desirable from the standpoint of ensuring visibility that the wiper blade is wiped immediately.

  Patent Document 1 discloses a vehicle wiper control device that immediately wipes away the washer liquid sprayed onto the windshield glass during high-speed traveling.

JP 2004-243937 A

  However, since the vehicle wiper control device described in Patent Document 1 injects the washer liquid even when the wiper device breaks down, there is a concern that it may be difficult to secure a view from the vehicle interior.

  FIG. 5 is a flowchart showing an example of a wiper operation status monitoring process of a general vehicle wiper control device. The process of FIG. 5 is started when the washer switch is turned on. In step 500, a wiper operation request signal for operating the wiper device is acquired from a command signal from the washer switch.

  In step 502, a washer operation request signal for operating the washer device is acquired from a command signal from the washer switch and the washer device is operated. In step 504, a wiper failure state is acquired based on the operation status of the wiper device.

  In step 506, it is determined whether or not there is a failure of the wiper motor. If the determination is affirmative, the operation of the wiper device is prohibited. If the determination is negative, the wiper device is operated. In addition, if the operation of the wiper device is prohibited, the washer liquid sprayed on the windshield glass cannot be wiped off.

  The present invention has been made in view of the above, and an object of the present invention is to provide a wiper device that prevents unnecessary washer fluid from being ejected when a wiper motor fails.

  In order to solve the above-described problem, the wiper device according to claim 1 includes a wiper motor that wipes a wiper blade on the windshield glass by rotating an output shaft, and a washer that operates a washer that injects cleaning liquid onto the windshield glass. A motor and a control unit that operates the washer motor and the wiper motor in response to an input of an operation signal, and controls the operation of not operating the washer motor even if the operation signal is input when the wiper motor fails. Yes.

  According to this wiper device, when the wiper motor fails, it is possible to prevent unnecessary washer liquid from being ejected when the wiper motor fails by performing control so that the washer motor does not operate even when an operation signal is input. .

  A wiper device according to a second aspect includes a state detection sensor that detects a state of the wiper motor in the wiper device according to the first aspect, wherein the control unit is configured to detect the state of the wiper motor based on a detection result of the state detection sensor. Determine failure of wiper motor.

  According to this wiper device, the state of the wiper motor is determined by a sensor that detects an abnormality of the wiper motor.

  The wiper device according to claim 3 is the wiper device according to claim 2, wherein the state detection sensor is a rotation angle sensor that detects a rotation angle of a motor output shaft as a state of the wiper motor, and the control unit Determines that the wiper motor is out of order when the rotation angle detected by the rotation angle sensor during rotation control of the wiper motor does not change.

  According to this wiper device, an abnormality of the wiper motor can be detected based on the rotation angle of the output shaft of the wiper motor.

  The wiper device according to a fourth aspect is the wiper device according to the second aspect, wherein the state detection sensor is a current sensor that detects a current flowing through a coil of the wiper motor as a state of the wiper motor, and the control unit includes: When the current detected by the current sensor during the rotation control of the wiper motor is equal to or higher than the upper limit current value or lower than the lower limit current value, the wiper motor is determined to be faulty.

  According to this wiper device, an abnormality of the wiper motor can be detected based on the motor current of the wiper motor.

  The wiper device according to a fifth aspect is the wiper device according to the second aspect, wherein the state detection sensor is a voltage sensor that detects a voltage supplied from a power supply as a state of the wiper motor, and the control unit includes: When the voltage detected by the voltage sensor during the rotation control of the wiper motor is equal to or higher than the upper limit voltage value or lower than the lower limit voltage value, the wiper motor is determined to be faulty.

  According to this wiper device, the abnormality of the wiper motor can be detected based on the voltage value supplied to the wiper motor.

  The wiper device according to claim 6 is the wiper device according to claim 2, wherein the state detection sensor is a temperature sensor that detects a temperature of a drive circuit of the wiper motor as a state of the wiper motor, and the control unit When the temperature detected by the temperature sensor during the rotation control of the wiper motor is equal to or higher than the upper limit temperature, it is determined that the wiper motor is out of order.

  According to this wiper device, an abnormality of the wiper motor can be detected based on the circuit temperature.

It is the schematic which shows the structure of the wiper apparatus which concerns on embodiment of this invention. It is a circuit diagram showing typically the circuit of the wiper device concerning an embodiment of the invention. It is a block diagram showing the operation when the wiper motor of the wiper device fails. (A) is an example of the case where control is mainly performed by the control circuit, and (B) is the cooperation of the control circuit and the vehicle ECU. An example of performing control is shown. It is the flowchart which showed an example of the wiper operation condition monitoring process of the wiper apparatus which concerns on embodiment of this invention. It is the flowchart which showed an example of the wiper operation condition monitoring process of the general wiper control device for vehicles.

  FIG. 1 is a schematic diagram illustrating a configuration of a wiper device 10 according to the present embodiment. The wiper device 10 is for wiping the windshield glass 12 provided in a vehicle such as a passenger car, for example, and includes a pair of wipers 14 and 16, a wiper motor 18, a link mechanism 20, and a control circuit 22 It has.

  The wipers 14 and 16 include wiper arms 24 and 26 and wiper blades 28 and 30, respectively. The base end portions of the wiper arms 24 and 26 are respectively fixed to pivot shafts 42 and 44 described later, and the wiper blades 28 and 30 are respectively fixed to the distal end portions of the wiper arms 24 and 26.

  In the wipers 14 and 16, the wiper blades 28 and 30 reciprocate on the windshield glass 12 as the wiper arms 24 and 26 operate, and the wiper blades 28 and 30 wipe the windshield glass 12.

  The wiper motor 18 has an output shaft 32 that can rotate forward and reverse via a speed reduction mechanism 52 mainly composed of a worm gear. The link mechanism 20 includes a crank arm 34, a first link rod 36, and a pair of pivots. Lever 38, 40, a pair of pivot shafts 42, 44, and a second link rod 46 are provided.

  One end side of the crank arm 34 is fixed to the output shaft 32, and the other end side of the crank arm 34 is operably connected to one end side of the first link rod 36. The other end side of the first link rod 36 is operatively connected to a position near the end different from the end having the pivot shaft 42 of the pivot lever 38, and the end of the pivot lever 38 having the pivot shaft 42 is connected to the end of the first link rod 36. Both ends of the second link rod 46 are operably connected to different ends and the end of the pivot lever 40 corresponding to the end of the pivot lever 38.

  The pivot shafts 42 and 44 are operatively supported by a pivot holder (not shown) provided on the vehicle body, and ends of the pivot levers 38 and 40 having the pivot shafts 42 and 44 are interposed via the pivot shafts 42 and 44. The wiper arms 24 and 26 are fixed.

  In the wiper device 10, when the output shaft 32 rotates forward and backward at a rotation angle θ 1 within a predetermined range, the rotational force of the output shaft 32 is transmitted to the wiper arms 24 and 26 via the link mechanism 20. The wiper blades 28 and 30 reciprocate between the lower reversing position P2 and the upper reversing position P1 on the windshield glass 12 in accordance with the reciprocating operation 26. Although the value of θ1 can take various values depending on the configuration of the link mechanism of the wiper device, etc., in this embodiment, it is set to 140 ° as an example.

  In the wiper device 10 according to the present embodiment, as shown in FIG. 1, when the wiper blades 28 and 30 are positioned at the storage position P3, the crank arm 34 and the first link rod 36 are linear. It is configured to be made.

  The storage position P3 is provided below the lower inversion position P2. The wiper blades 28 and 30 are moved to the retracted position P3 by rotating the output shaft 32 by θ2 from the state where the wiper blades 28 and 30 are in the lower inversion position P2. The value of θ2 can take various values depending on the configuration of the link mechanism of the wiper device, etc., but in this embodiment, it is 10 ° as an example.

  When θ2 is “0”, the lower inversion position P2 coincides with the storage position P3, and the wiper blades 28 and 30 are stopped and stored at the lower inversion position P2.

  A control circuit 22 for controlling the rotation of the wiper motor 18 is connected to the wiper motor 18. The control circuit 22 according to the present embodiment generates, for example, a rotation angle sensor 54 that detects the rotation speed and rotation angle of the output shaft 32 of the wiper motor 18 and a current for operating the wiper motor 18 by pulse width modulation (PWM). The drive circuit 56 is supplied to the wiper motor 18.

  Since the wiper motor 18 according to the present embodiment has the speed reduction mechanism 52 as described above, the rotation speed and rotation angle of the output shaft 32 are not the same as the rotation speed and rotation angle of the wiper motor main body. However, in the present embodiment, since the wiper motor main body and the speed reduction mechanism 52 are inseparably configured, hereinafter, the rotation speed and rotation angle of the output shaft 32 are regarded as the rotation speed and rotation angle of the wiper motor 18. .

  The rotation angle sensor 54 is provided in the speed reduction mechanism 52 of the wiper motor 18 and detects a magnetic field (magnetic force) of an excitation coil or a magnet that rotates in conjunction with the output shaft 32 by converting it into a current.

  The control circuit 22 can calculate the position of the wiper blade on the windshield glass 12 from the rotation angle of the output shaft 32 detected by the rotation angle sensor 54 so that the rotation speed of the output shaft 32 changes according to the position. A microcomputer 58 that controls the drive circuit 56 is included. The control circuit 22 is provided with a memory 60 that is a storage device that stores data and programs used to control the drive circuit 56. The memory 60 stores data and a program for calculating the rotation speed of the output shaft 32 in accordance with the position of the wiper blades 28 and 30 on the windshield glass 12. The microcomputer 58 is connected to a vehicle ECU (Electronic Control Unit) 90 that supervises control of the engine of the vehicle.

  A rain sensor 76 that detects water droplets on the surface of the windshield glass 12 is connected to the vehicle ECU 90.

  The wiper switch 50 is a switch that turns on or off the power supplied from the vehicle battery to the wiper motor 18. The wiper switch 50 includes a low-speed operation mode selection position for operating the wiper blades 28 and 30 at a low speed, a high-speed operation mode selection position for operation at a high speed, an intermittent operation mode selection position for intermittent operation at a constant period, and a rain sensor 76 It is possible to switch to an AUTO (auto) operation mode selection position and a storage (stop) mode selection position that are activated when raindrops are detected. Further, a signal corresponding to the selected position of each mode is output to the microcomputer 58 via the vehicle ECU 90.

  When a signal output from the wiper switch 50 according to the selected position of each mode is input to the microcomputer 58 via the vehicle ECU 90, the microcomputer 58 controls the memory 60 to control corresponding to the output signal from the wiper switch 50. This is done using stored data and programs.

  The washer switch 62 is a switch that turns on or off the power supplied from the vehicle battery to the washer motor 64 and the wiper motor 18. The washer switch 62 is provided integrally with an operating means such as a lever provided with the above-described wiper switch 50, for example, and the wiper motor 18 and the washer motor are operated while an operation such as pulling the lever etc. to the hand is continued. 64 is activated.

  The washer pump 66 is driven by the rotation of the washer motor 64, and the washer pump 66 pumps the washer liquid in the washer liquid tank 68 to the driver seat side hose 72A or the passenger seat side hose 72B. The driver seat side hose 72A is connected to a driver seat side nozzle 74A provided below the driver seat side of the windshield glass 12. Further, the passenger seat side hose 72B is connected to a passenger seat side nozzle 74B provided below the windshield glass 12 on the passenger seat side.

  The intermittent volume 92 is a switch for changing the cycle in which the wiper blades 28 and 30 operate intermittently when the wiper switch 50 is in the intermittent operation mode selection position.

  The rain sensor 76 includes, for example, an LED that is an infrared light emitting element, a photodiode that is a light receiving element, a lens that forms an infrared optical path, and a control circuit. The infrared rays radiated from the LED are totally reflected by the windshield glass 12. However, if water droplets are present on the surface of the windshield glass 12, some of the infrared rays pass through the waterdrops and are emitted to the outside. The amount of reflection decreases. As a result, the amount of light entering the photodiode that is the light receiving element is reduced. Based on such a decrease in the amount of light, water droplets on the surface of the windshield glass 12 are detected.

  FIG. 2 is a circuit diagram schematically showing a circuit of the wiper device 10 according to the present embodiment. As shown in FIG. 2, the wiper device 10 includes a wiper drive circuit 88 that drives the wiper motor 18 to reciprocate the wiper arms 24 and 26 that are connected to the output shaft 32 via a link mechanism, and a washer motor 64. A pump drive circuit 57 to be driven, a wiper drive circuit 88, a drive circuit 56 to drive the pump drive circuit 57, and a control circuit 22 to control the drive circuit 56 are included. The control circuit 22 of the wiper apparatus 10 according to the present embodiment includes the microcomputer 58 shown in FIG. 2, and the drive circuit 56 includes a pre-driver 98, a relay drive circuit 78, and an FET drive circuit 80. Yes. A wiper switch 50, a washer switch 62, a rain sensor 76, and an intermittent volume 92 are connected to the microcomputer 58 via a vehicle ECU 90 (not shown).

  The wiper drive circuit 88 includes four FETs 82A to 82D. The FET 82A has a drain connected to the power supply (+ B), a gate connected to the pre-driver 98, and a source connected to one end of the wiper motor 18. The FET 82B has a drain connected to the power supply (+ B), a gate connected to the pre-driver 98, and a source connected to the other end of the wiper motor 18. The FET 82C has a drain connected to one end of the wiper motor 18, a gate connected to the pre-driver 98, and a source grounded. The FET 82D has a drain connected to the other end of the wiper motor 18, a gate connected to the pre-driver 98, and a source grounded.

  The pre-driver 98 controls driving of the wiper motor 18 by switching control signals supplied to the gates of the FETs 82A to 82D. That is, when the predriver 98 rotates the output shaft 32 of the wiper motor 18 in a predetermined direction, the pre-driver 98 turns on the set of the FET 82A and FET 82D, and rotates the output shaft 32 of the wiper motor 18 in the direction opposite to the predetermined direction. The pair of FET 82B and FET 82C is turned on. Further, the pre-driver 98 performs PWM for changing the ratio (duty ratio) of the time during which the set of the FETs 82 to be turned on is turned on in a predetermined control cycle in accordance with the target rotational speed of the output shaft 32 of the wiper motor 18. . By the above control, the rotation direction and the rotation speed of the output shaft 32 of the wiper motor 18 are controlled.

  The pump drive circuit 57 includes a relay unit 84 incorporating two relays RLY1 and RLY2, and two FETs 86A and 86B. The relay coils of the relays RLY1 and RLY2 of the relay unit 84 are connected to the relay drive circuit 78, respectively. The relay drive circuit 78 switches the relays RLY1 and RLY2 on and off (excitation / excitation stop of the relay coil). The relays RLY1 and RLY2 maintain the state where the common terminal 84C is connected to the first terminal 84A (the state shown in FIG. 2: the off state) while the relay coil is not excited, and the relay coil is excited. And the common terminal 84C is switched to a state of connecting to the second terminal 84B. The common terminal 84C of the relay RLY1 is connected to one end of the washer motor 64, and the common terminal 84C of the relay RLY2 is connected to the other end of the washer motor 64. The first terminals 84A of the relays RLY1 and RLY2 are connected to the drain of the FET 86B, and the second terminals 84B of the relays RLY1 and RLY2 are connected to the power supply (+ B).

  The gate of the FET 86B is connected to the FET drive circuit 80, and the source is grounded. The FET drive circuit 80 controls the duty ratio of the on time of the FET 86B and the on time of the FET 86B (the ratio of the time during which the FET 86B is on in a predetermined control period). An FET 86A is provided between the drain of the FET 86B and the power supply (+ B). The FET 86A is provided for the purpose of using a parasitic diode for absorbing a surge without switching on and off because no control signal is input to the gate.

  The relay drive circuit 78 and the FET drive circuit 80 control the drive of the washer motor 64 by switching on and off the two relays RLY1, RLY2 and the FET 86B. That is, when the output shaft of the washer motor 64 is rotated in a predetermined direction, the relay drive circuit 78 turns on the relay RLY1 (relay RLY2 is off), and the FET drive circuit 80 turns on the FET 86B with a predetermined duty ratio. With the above control, the rotation speed of the output shaft of the washer motor 64 is controlled. Although not shown in FIG. 2, the circuit of the wiper device 10 according to the present embodiment includes a voltage sensor that detects the voltage of the battery that is a power source, and a current (motor current) that flows through the coil of the wiper motor 18. A current sensor for detecting, a temperature sensor for detecting the temperature of the substrate of the drive circuit 56, and the like are mounted.

  FIG. 3 is a block diagram showing the operation when the wiper motor 18 of the wiper apparatus 10 fails. FIG. 3A shows an example in which control is performed mainly by the control circuit 22, and FIG. 22 shows an example in which the vehicle ECU 90 performs control in cooperation.

  FIG. 3A is performed in the case of the configuration shown in FIG. 2, and the control circuit 22 performs “1: wiper failure detection” that detects an abnormality in the wiper motor 18 and the drive circuit 56. Then, “2: wiper motor operation prohibition” control for stopping the rotation of the wiper motor 18 and “2: washer motor operation prohibition” control for prohibiting the operation of the washer motor 64 are performed.

  FIG. 3B is performed when the washer motor 64 is controlled by the vehicle ECU 90. The wiper motor 18 control circuit 22 performs “1: wiper failure detection” that detects an abnormality in the wiper motor 18 and the drive circuit 56. Then, control of “2: wiper motor operation prohibition” for stopping the rotation of the wiper motor 18 is performed, and “2: wiper motor failure state” indicating that the wiper motor 18 has failed is notified to the vehicle ECU 90. The vehicle ECU 90 performs control of “3: prohibition of washer motor operation” for prohibiting the operation of the washer motor 64 based on the notified “2: wiper motor failure state”.

  In the present embodiment, when the battery voltage is equal to or higher than the upper limit value or lower limit value, when the motor current of the wiper motor 18 is equal to or higher than the upper limit value or lower limit value, the substrate temperature of the drive circuit 56 becomes equal to or higher than the predetermined value. If the rotation angle of the output shaft 32 detected by the rotation angle sensor 54 does not change even when the wiper motor 18 is energized, it is determined that the wiper device 10 has failed. To do.

  FIG. 4 is a flowchart showing an example of the wiper operation status monitoring process of the wiper apparatus 10 according to the present embodiment. The process of FIG. 4 is started when the washer switch 62 is turned on. In step 400, a wiper operation request signal for operating the wiper device 10 is acquired from a command signal from the washer switch 62.

  In step 402, a washer operation request signal for operating the washer motor 64 is acquired from a command signal from the washer switch 62, and in step 404, a wiper failure state is acquired based on the operation status of the wiper device 10 as described above. .

  In step 406, it is determined whether or not the wiper device 10 has failed. If the determination in step 406 is affirmative, the rotation of the wiper motor 18 is stopped and the operation of the wiper device 10 is prohibited in step 408, and then the operation of the washer motor 64 is prohibited in step 410. Return.

  If the determination in step 406 is negative, the process is returned without prohibiting the wiper operation and the washer operation.

  As described above, according to the wiper device 10 according to the present embodiment, when the wiper device 10 breaks down, the wiper device 10 is prohibited from operating and the washer motor 64 is prohibited from operating. It is possible to prevent unnecessary washer liquid from being ejected when the apparatus breaks down.

DESCRIPTION OF SYMBOLS 10 ... Wiper apparatus, 12 ... Windshield glass, 14, 16 ... Wiper, 18 ... Wiper motor, 20 ... Link mechanism, 22 ... Control circuit, 24, 26 ... Wiper arm, 28, 30 ... Wiper blade, 32 ... Output shaft, 34 ... Crank arm, 36 ... Link rod, 38, 40 ... Pivot lever, 42, 44 ... Pivot shaft, 46 ... Link rod, 50 ... Wiper switch, 52 ... Reduction mechanism, 54 ... Rotation angle sensor, 56 ... Drive circuit, 57 ... Pump drive circuit,
58 ... Microcomputer, 60 ... Memory, 62 ... Washer switch, 64 ... Washer motor, 66 ... Washer pump, 68 ... Washer liquid tank, 72A ... Driver side hose, 72B ... Passenger side hose, 74A ... Driver side nozzle 74B ... Passenger side nozzle, 76 ... Rain sensor, 78 ... Relay drive circuit, 80 ... FET drive circuit, 82A, 82B, 82C, 82D ... FET, 84 ... Relay unit, 84A ... First terminal, 84B ... Second Terminal, 84C ... Common terminal, 86A, 86B ... FET, 88 ... Wiper drive circuit, 90 ... Vehicle ECU, 92 ... Intermittent volume, 98 ... Pre-driver, RLY1, RLY2 ... Relay, θ1 ... Rotation angle, P1 ... Upper reverse position , P2 ... lower inversion position, P3 ... storage position

Claims (6)

A wiper motor that wipes the wiper blade on the windshield glass by rotating the output shaft;
A washer motor for operating a washer for injecting cleaning liquid onto the windshield glass;
A control unit that operates the washer motor and the wiper motor by inputting an operation signal, and that controls the washer motor not to be operated even when the operation signal is input when the wiper motor has failed.
Including wiper device.   The wiper device according to claim 1, further comprising a state detection sensor that detects a state of the wiper motor, wherein the control unit determines a failure of the wiper motor based on a detection result of the state detection sensor.   The state detection sensor is a rotation angle sensor that detects a rotation angle of a motor output shaft as a state of the wiper motor, and the control unit changes a rotation angle detected by the rotation angle sensor during rotation control of the wiper motor. The wiper device according to claim 2, wherein the wiper motor is determined to be faulty if not.   The state detection sensor is a current sensor that detects a current flowing through the coil of the wiper motor as the state of the wiper motor, and the control unit detects that the current detected by the current sensor during rotation control of the wiper motor is equal to or greater than an upper limit current value. The wiper device according to claim 2, wherein the wiper motor is determined to be faulty when the current value is equal to or lower than a lower limit current value.   The state detection sensor is a voltage sensor that detects a voltage supplied from a power source as the state of the wiper motor, and the control unit detects that the voltage detected by the voltage sensor during rotation control of the wiper motor is equal to or higher than an upper limit voltage value. The wiper device according to claim 2, wherein the wiper motor is determined to be faulty when the voltage is equal to or lower than a lower limit voltage value.   The state detection sensor is a temperature sensor that detects the temperature of the wiper motor drive circuit as the state of the wiper motor, and the control unit detects that the temperature detected by the temperature sensor during rotation control of the wiper motor is equal to or higher than an upper limit temperature. The wiper device according to claim 2, wherein the wiper motor is determined to be faulty.