Patent Publication Number: US-2022227333-A1

Title: Vehicular air curtain device, vehicular cleaner system, and vehicular air curtain system

Description:
TECHNICAL FIELD 
     The present invention relates to a vehicular air curtain device, a vehicular cleaner system equipped with the vehicular air curtain device, and a vehicular air curtain system. 
     BACKGROUND ART 
     In recent years, the number of vehicles equipped with an in-vehicle camera to shoot vehicle surroundings is increasing. A lens of the in-vehicle camera, which is an imaging surface, may become dirty due to a raindrop, mud, or the like. Known in the related art is a device for removing a foreign object by ejecting cleaning liquid, compressed air, and the like to the lens of the in-vehicle camera in order to remove a foreign object, such as a drop of water, adhering to the lens. 
     For example, Patent Literature 1 discloses a vehicular cleaner system including a nozzle that ejects cleaning liquid and high-pressure air toward a cleaning surface of an in-vehicle camera. The nozzle disclosed in Patent Literature 1 has a first ejection port for ejecting the cleaning liquid toward the cleaning surface and a second ejection port for ejecting the high-pressure air toward the cleaning surface. 
     Patent Literature 2 discloses a vehicular cleaner that cleans an in-vehicle camera by blowing air onto the in-vehicle camera at a high pressure. 
     CITATION LIST 
     Patent Literature 
     Patent Literature 1: WO 2018/123517 A1; Patent Literature 2: JP2001-171491A 
     SUMMARY OF INVENTION 
     Technical Problem 
     In the vehicular cleaner system disclosed in Patent Literature 1, the ejection port of the cleaning liquid and the ejection port of the high-pressure air are provided in the same nozzle. As a result, when the high-pressure air is ejected during the ejection of the cleaning liquid, the cleaning liquid may be foamed by blowing the high-pressure air to the cleaning liquid at high speed. Therefore, the arrangement of the ejection port of the air to the ejection port of the cleaning liquid needs to be improved. 
     In addition, in the vehicular cleaner system disclosed in Patent Literature 1, when the high-pressure air is ejected during the ejection of the cleaning liquid, the cleaning liquid foamed by the high-pressure air accumulates in the ejection port, and thus the vehicular cleaner system needs to be improved in order to maintain ejection performance of the cleaning liquid. 
     Further, the inventors of the present invention conceived a device for preventing water, snow, dust, and the like from adhering to, unlike the cleaner disclosed in Patent Literature 2, a sensor such as a camera. This is because once snow adheres to the camera, it is very difficult to remove the snow. 
     In a traveling environment in which foreign objects are liable to adhere, however, since such a device is continuously operated for a long time, power consumption is prone to increase. 
     An object of the present invention is to provide a vehicular cleaner system that cleans a cleaning object mounted on a vehicle with cleaning liquid and air and can prevent the cleaning liquid from being foamed. 
     Another object of the present invention is to provide a vehicular cleaner system that prevents a foreign object from adhering to a cleaning object mounted on a vehicle by an air curtain, washes off an adhering foreign object with cleaning liquid, and can maintain ejection performance of the cleaning liquid. 
     Another object of the present invention is to provide a vehicular air curtain device and a vehicular cleaner system that can reduce power consumption. 
     Another object of the present invention is to provide a vehicular air curtain system that is operated only when necessary to reduce power consumption. 
     Solution to Problem 
     In order to achieve at least one of the above objects, a vehicular cleaner system according to one aspect of the present invention is a system for cleaning a cleaning object mounted on a vehicle, the vehicular cleaner system includes: 
     a washer configured to eject cleaning liquid toward the cleaning object from a liquid nozzle; and 
     a blower configured to eject air toward the cleaning object from an air nozzle, in which 
     directions of ejection ports of the liquid nozzle and the air nozzle are perpendicular to each other. 
     According to the vehicular cleaner system of the present aspect, the directions of the ejection ports of the liquid nozzle and the air nozzle are perpendicular to each other, and thus the ejection ports of the liquid nozzle and the air nozzle are arranged apart to a certain extent. Accordingly, it is possible to prevent the cleaning liquid from being foamed by the ejection of the air and to clean the cleaning object effectively. 
     In order to achieve at least one of the above objects, a vehicular cleaner system according to another aspect of the present invention is a system for cleaning a cleaning object mounted on a vehicle, the vehicular cleaner system includes: 
     a washer configured to eject cleaning liquid toward the cleaning object from a liquid nozzle; 
     an air curtain device configured to send air continuously to the cleaning object at a predetermined wind speed or a predetermined air flow rate from an air nozzle to prevent dirt from adhering to the cleaning object; and 
     a control unit configured to control the washer and the air curtain device, in which 
     the control unit controls the air curtain device to reduce a wind speed or an air flow rate of the air ejected from the air nozzle while the cleaning liquid is being ejected from the liquid nozzle. 
     According to the vehicular cleaner system of the present aspect, it is possible to prevent a foreign object from adhering to the cleaning object by an air curtain formed by the air ejected from the air nozzle and to wash off an adhering foreign object with the cleaning liquid. In addition, it is possible to prevent an adverse effect of the air curtain, such as a problem that the cleaning liquid is foamed by the air continuously blown above a certain wind speed (air flow rate) during the ejection of the cleaning liquid and the foam from accumulating in the ejection port of the liquid nozzle. Accordingly, it is possible to maintain ejection performance of the cleaning liquid. 
     In order to achieve at least one of the above objects, a vehicular cleaner system according to another aspect of the present invention is a system for cleaning a cleaning object mounted on a vehicle, the vehicular cleaner system includes: 
     a washer configured to eject cleaning liquid toward the cleaning object from a liquid nozzle; 
     an air curtain device configured to send air continuously to the cleaning object at a predetermined wind speed or a predetermined air flow rate from an air nozzle to prevent dirt from adhering to the cleaning object; and 
     a control unit configured to control the washer and the air curtain device, in which 
     the control unit stops, based on an operation signal for operating the washer, power supply to a first motor configured to drive the air curtain device. 
     According to the vehicular cleaner system of the present aspect, it is possible to curb an adverse effect of the air curtain during the ejection of the cleaning liquid. Accordingly, it is possible to maintain ejection performance of the cleaning liquid. 
     In order to achieve at least one of the above objects, a vehicular air curtain device according to another aspect of the present invention is a vehicular air curtain device configured to send continuously, based on an operation signal, air to a sensor or a sensor cover mounted on a vehicle at a predetermined wind speed or a predetermined air flow rate in order to prevent dirt from adhering to the sensor or the sensor cover, the vehicular air curtain device includes: 
     an air blowing mechanism; 
     a motor configured to drive the air blowing mechanism; and 
     an air curtain control unit configured to change a drive voltage or a drive current of the motor in accordance with a predetermined condition. 
     According to another aspect of the present invention, a vehicular cleaner system includes: 
     the vehicular air curtain device described above; 
     a cleaner device configured to wash off dirt adhering to the sensor or the sensor cover mounted on the vehicle; and 
     an integrative control unit configured to control the vehicular air curtain device and the cleaner device. 
     In order to achieve at least one of the above objects, a vehicular air curtain system according to another aspect of the present invention includes: 
     a vehicular air curtain device configured to send air continuously to a sensor or a sensor cover mounted on a vehicle at a predetermined wind speed or a predetermined air flow rate to prevent dirt from adhering to the sensor or the sensor cover; 
     an information acquisition unit configured to acquire information indicating bad weather; and 
     a control unit configured to control the vehicular air curtain device, in which 
     the control unit operates the vehicular air curtain device based on the information indicating bad weather acquired by the information acquisition unit. 
     According to the vehicular air curtain system of the present aspect, the vehicular air curtain device is operated only when it is determined that it is raining or snowing. Accordingly, the power consumption of the system can be reduced. 
     Advantageous Effects of Invention 
     According to the present invention, it is possible to provide a vehicular cleaner system that can clean a cleaning object mounted on a vehicle with cleaning liquid and air, and can prevent the cleaning liquid from being foamed. 
     According to the present invention, it is possible to provide a vehicular cleaner system that prevents a foreign object from adhering to the cleaning object mounted on the vehicle by an air curtain, washes off an adhering foreign object with cleaning liquid, and can maintain ejection performance of the cleaning liquid. 
     According to the present invention, it is possible to provide a vehicular air curtain device and a vehicular cleaner system that can reduce power consumption. 
     According to the present invention, it is possible to provide a vehicular air curtain system that is operated only when necessary to reduce power consumption. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a top view showing a vehicle equipped with a vehicular cleaner system according to a first embodiment. 
         FIG. 2  is a block diagram showing a vehicle system. 
         FIG. 3  is a block diagram showing the vehicular cleaner system of  FIG. 1 . 
         FIG. 4  is a perspective view showing an example of a cleaning object, and a cleaner device and an air curtain device that are provided in the vehicular cleaner of  FIG. 1 . 
         FIG. 5  is a perspective view showing the cleaner device shown of  FIG. 4 . 
         FIG. 6  is a view showing rotation of liquid nozzles of the cleaner device of  FIG. 4 . 
         FIG. 7  is an exploded perspective view showing an air curtain device provided in the cleaner device of  FIG. 5 . 
         FIG. 8  is a schematic view showing positions of the cleaner device and the air curtain device attached to a cleaning object. 
         FIG. 9  is a schematic diagram showing positions of a cleaner device and an air curtain device attached to a cleaning object according to a first modification. 
         FIG. 10  is a schematic diagram showing a cleaning object, a cleaner device, and an air curtain device according to a second modification. 
         FIG. 11  is a perspective view showing a cleaning object, a cleaner device, and an air curtain device according to a third modification. 
         FIG. 12  is a timing chart showing operation signals of an air curtain and a washer and operation states of the air curtain and a cleaner of a cleaner system according to a second embodiment. 
         FIG. 13  is a timing chart showing operation signals of an air curtain and a washer and operation states of the air curtain and a cleaner of a cleaner system according to a third embodiment. 
         FIG. 14  is a block diagram showing an air curtain device according to a fourth embodiment. 
         FIG. 15  is a vehicle side view showing a cleaning object attached to the rear of a vehicle. 
         FIG. 16  is a block diagram showing a vehicular air curtain system according to a fifth embodiment. 
         FIG. 17  is a block diagram showing an air curtain device provided in the vehicular air curtain system of  FIG. 16 . 
         FIG. 18  is a timing chart showing a relationship between a wiper operation signal and an air curtain operation signal. 
         FIG. 19  is a timing chart showing a relationship among a wiper operation signal, a temperature around the vehicle, and an air curtain operation signal. 
         FIG. 20  is a timing chart showing a relationship between image determination and an air curtain operation signal. 
         FIG. 21  is a timing chart showing a relationship between weather information and an air curtain operation signal. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     In the following, embodiments of the present invention will be described with reference to the drawings. Components having the same reference numerals as those already described in the description of embodiments will be omitted for the sake of simplicity. Dimensions of components in the drawings may be different from actual dimensions for the sake of convenience. 
     In the description of embodiments, a “left-right direction,” a “front-rear direction,” and an “upper-lower direction” are will be referred to for the sake of convenience. These directions are relative directions set for a vehicle  1  of  FIG. 1 . The “upper-lower direction” includes an “upper direction” and a “lower direction.” The “front-rear direction” includes a “front direction” and a “rear direction.” The “left-right direction” includes a “left direction” and a “right direction.” 
     First Embodiment 
       FIG. 1  is a top view showing a vehicle  1  equipped with a vehicular cleaner system  100  (hereinafter, referred to as a cleaner system  100 ) according to a first embodiment. The vehicle  1  includes the cleaner system  100 . In the present embodiment, the vehicle  1  can travel in self-driving mode. 
     First, a vehicle system  2  of the vehicle  1  will be described with reference to  FIG. 2 .  FIG. 2  is a block diagram showing the vehicle system  2 . As shown in  FIG. 2 , the vehicle system  2  includes: a vehicle control unit  3 ; an internal sensor  5 ; an external sensor  6 ; a lamp  7 ; a human machine interface (HMI)  8 ; a global positioning system (GPS)  9 ; a wireless communication unit  10 ; and a map information storage unit  11 . The vehicle system  2  further includes: a steering actuator  12 ; a steering device  13 ; a brake actuator  14 ; a brake device  15 ; an accelerator actuator  16 ; and an accelerator device  17 . 
     The vehicle control unit  3  is configured with an electronic control unit (ECU). The vehicle control unit  3  includes: a processor, such as a central processing unit (CPU); a read-only memory (ROM) storing various vehicle control programs; and a random-access memory (RAM) temporarily storing various vehicle control data. The processor is configured to load a program designated by a vehicle control program stored in the ROM onto the RAM to execute a variety of processing in cooperation with the RAM. The vehicle control unit  3  is configured to control traveling of the vehicle  1 . 
     The internal sensor  5  is configured to acquire information about a host vehicle. The internal sensor  5  is, for example, at least one of an accelerometer, a (vehicle) speed sensor, a wheel speed sensor, and a gyroscope. The internal sensor  5  is configured to acquire information about the host vehicle including a traveling state of the vehicle  1  to output the information to the vehicle control unit  3 . The internal sensor  5  may include: a seat occupancy sensor configured to detect whether a driver sits on a driver seat; a face orientation sensor configured to detect an orientation of the driver&#39;s face; a motion detector configured to detect whether there is a person in the vehicle; and the like. 
     The external sensor  6  is configured to acquire information about the outside of the host vehicle. The external sensor is, for example, at least one of a camera, a radar, a LiDAR, and the like. The external sensor  6  is configured to acquire information about the outside of the host vehicle including surroundings (another vehicle, a pedestrian, a road shape, a traffic sign, an obstacle, and the like) of the vehicle  1  to output the information to the vehicle control unit  3 . The external sensor  6  may include: a weather sensor (for example, a rain sensor, a hygrometer, a thermometer, and the like) configured to detect weather conditions; an illuminance sensor configured to detect illuminance around the vehicle  1 ; or the like. 
     The camera includes, for example, an image sensor, such as a charge-coupled device (CCD) and a complementary metal-oxide-semiconductor (CMOS) and is configured to detect visible light or infrared light. 
     The radar is a millimeter-wave radar, a microwave radar, a laser radar, or the like. LiDAR stands for “light detection and ranging” or “laser imaging detection and ranging.” In general, LiDAR is a sensor configured to emit invisible light ahead and acquire information, such as a distance to an object, a shape of the object, and a material of the object, based on the emitted light and returned light. 
     The lamp  7  is at least one of: a headlamp or a position lamp, which are provided at the front of the vehicle  1 ; a rear combination lamp, which is provided at the rear of the vehicle  1 ; a turn signal lamp, which is provided at the front or the side of the vehicle; a lamp for conveying a state of the host vehicle to a pedestrian or a driver of another vehicle; and the like. 
     The HMI  8  includes: an input unit configured to receive an input operation from the driver; and an output unit configured to output traveling information or the like to the driver. The input unit includes: a steering wheel; an accelerator pedal; a brake pedal; a driving-mode selecting switch for switching driving modes of the vehicle  1 ; a wiper operator for operating a wiper; and the like. The output unit is a display configured to display a variety of traveling information. 
     The GPS  9  is configured to acquire current location information of the vehicle  1  to output the acquired current location information to the vehicle control unit  3 . The wireless communication unit  10  is configured to receive traveling information of another vehicle around the vehicle  1  from the another vehicle and to transmit traveling information of the vehicle  1  to the another vehicle (vehicle-to-vehicle communication). The wireless communication unit  10  is configured to receive infrastructure information from an infrastructure facility, such as traffic lights and a traffic sign, and to transmit traveling information of the vehicle  1  to the infrastructure facility (vehicle-to-infrastructure communication). For example, the wireless communication unit  10  is configured to receive weather information (for example, information of Vehicle Information and Communication System (VICS, registered trademark)) around the host vehicle from the infrastructure facility via a network or the like. The map information storage unit  11  is an external storage device, such as a hard disk drive, configured to store map information and is configured to output the map information to the vehicle control unit  3 . 
     When the vehicle  1  travels in self-driving mode, the vehicle control unit  3  automatically generates, based on the traveling state information, the surrounding information, the current position information, the map information, and the like, at least one of a steering control signal, an accelerator control signal, and a brake control signal. The steering actuator  12  is configured to receive the steering control signal from the vehicle control unit  3  to control the steering device  13  based on the received steering control signal. The brake actuator  14  is configured to receive the brake control signal from the vehicle control unit  3  to control the brake device  15  based on the received brake control signal. The accelerator actuator  16  is configured to receive the accelerator control signal from the vehicle control unit  3  to control the accelerator device  17  based on the received accelerator control signal. In this way, traveling of the vehicle  1  is automatically controlled by the vehicle system  2  in the self-driving mode. 
     On the other hand, when the vehicle  1  travels in manual driving mode, the vehicle control unit  3  generates the steering control signal, the accelerator control signal, and the brake control signal in accordance with the driver&#39;s manual operation on the accelerator pedal, the brake pedal, and the steering wheel. In this way, since the steering control signal, the accelerator control signal, and the brake control signal are generated by the driver&#39;s manual operation in the manual driving mode, the traveling of the vehicle  1  is controlled by the driver. 
     Next, driving modes of the vehicle  1  will be described. The driving modes includes self-driving mode and manual driving mode. The self-driving mode includes full automation mode, advanced driver assistance mode, and a driver assistance mode. In the full automation mode, the vehicle system  2  automatically performs all of steering control, brake control, and accelerator control, and the driver cannot drive the vehicle  1 . In the advanced driver assistance mode, the vehicle system  2  automatically performs all of the steering control, the brake control, and the accelerator control, and the driver can but does not drive the vehicle  1 . In the driver assistance mode, the vehicle system  2  automatically performs some of the steering control, the brake control, and the accelerator control, and the driver drives the vehicle  1  with driving assistance of the vehicle system  2 . On the other hand, in the manual driving mode, the vehicle system  2  does not automatically perform traveling control, and the driver drives the vehicle  1  without the driving assistance of the vehicle system  2 . 
     The driving modes of the vehicle  1  may be switched by operating the driving-mode selecting switch. In this case, the vehicle control unit  3  switches the driving modes of the vehicle  1  among four driving modes (the full automation mode, the advanced driver assistance mode, the driver assistance mode, and the manual driving mode) in accordance with the driver&#39;s operation on the driving-mode selecting switch. The driving modes of the vehicle  1  may be automatically switched based on information indicating a traveling-permitted section in which a self-driving car is permitted to travel or a traveling-prohibited section in which a self-driving car is prohibited from traveling or based on information about weather conditions of the outside. In this case, the vehicle control unit  3  switches the driving modes of the vehicle  1  based on the information described above. in addition, the driving modes of the vehicle  1  may be automatically switched using the seat occupancy sensor, the face orientation sensor, or the like. In this case, the vehicle control unit  3  switches the driving modes of the vehicle  1  based on an output signal from the seat occupancy sensor or the face orientation sensor. 
     The vehicle  1  of  FIG. 1  includes, as the external sensor  6 , a front LiDAR  6   f , a rear LiDAR  6   b , a right LiDAR  6   r , a left LiDAR  6   l , a front camera  6   c , and a rear camera  6   d . The front LiDAR  6   f  is configured to acquire information about the front side of the vehicle  1 . The rear LiDAR  6   b  is configured to acquire information about the rear side of the vehicle  1 . The right LiDAR  6   r  is configured to acquire information about the right side of the vehicle  1 . 
     The left LiDAR  6   l  is configured to acquire information about the left side of the vehicle  1 . The front camera  6   c  is configured to acquire information about the front side of the vehicle  1 . The rear camera  6   d  is configured to acquire information about the rear side of the vehicle  1 . 
     Although the front LiDAR  6   f  is provided at the front of the vehicle  1 , the rear LiDAR  6   b  is provided at the rear of the vehicle  1 , the right LiDAR  6   r  is provided at the right of the vehicle  1 , and the left LiDAR  6   l  is provided at the left of the vehicle  1  in the example of  FIG. 1 , the present invention is not limited thereto. For example, the front LiDAR, the rear LiDAR, the right LiDAR, and the left LiDAR may be disposed together at a roof of the vehicle  1 . 
     The vehicle  1  includes, as the lamp  7 , a right headlamp  7   r  and a left headlamp  7   l . The right headlamp  7   r  is provided in the right of the front of the vehicle  1 , and the left headlamp  7   l  is provided in the left of the front of the vehicle  1 . The right headlamp  7   r  is provided to the right of the left headlamp  7   l.    
     The vehicle  1  includes a front window  1   f  and a rear window  1   b.    
     The vehicle  1  includes the cleaner system  100  according to an embodiment of the present invention. The cleaner system  100  is a system to remove a foreign object, such as a drop of water, mud, and dust, adhering to a cleaning object or to prevent a foreign object from adhering to the cleaning object. 
     In the present embodiment, the cleaner system  100  includes: a front window washer unit (hereinafter, referred to as a front WW)  101  configured to clean the front window  1   f ; and a rear window washer unit (hereinafter, referred to as a rear WW)  102  configured to clean the rear window  1   b.    
     The cleaner system  100  further includes: a front LiDAR cleaner unit (hereinafter, referred to as a front LC)  103  configured to clean the front LiDAR  6   f ; and a rear LiDAR cleaner unit (hereinafter, referred to as a rear LC)  104  configured to clean the rear LiDAR  6   b . 
     The cleaner system  100  further includes: a right LiDAR cleaner unit (hereinafter, referred to as a right LC)  105  configured to clean the right LiDAR  6   r ; and a left LiDAR cleaner unit (hereinafter, referred to as a left LC)  106  configured to clean the left LiDAR  6   l.    
     The cleaner system  100  further includes: a right headlamp cleaner unit (hereinafter, referred to as a right HC)  107  configured to clean the right headlamp  7   r ; and a left headlamp cleaner unit (hereinafter, referred to as a left HC)  108  configured to clean the left headlamp  7   l . 
     The cleaner system  100  further includes: a front camera cleaner unit  109   a  configured to clean the front camera  6   c ; and a rear camera cleaner unit  109   b  configured to clean the rear camera  6   d . Each of the cleaners  101  to  109   b  includes one or more nozzles and is configured to eject a cleaning medium, such as cleaning liquid and air, from the nozzles toward the cleaning object. 
       FIG. 3  is a block diagram showing the cleaner system  100 . The cleaner system  100  includes: the cleaners  101  to  109   b  described above; and an integrative control unit  111  configured to control the cleaners  101  to  109   b . In  FIG. 3 , the front LC  103 , the front camera cleaner unit  109   a , the rear LC  104 , and the rear camera cleaner unit  109   b  out of the cleaners  101  to  109   b  described above are shown, and the front WW  101 , the rear WW  102 , the right LC  105 , the left LC  106 , the right HC  107 , and the left HC  108  are not shown. 
     The front LC  103  includes: a first cleaner device  120  (an example of a washer) configured to wash off dirt, such as a foreign object, adhering to the front LiDAR  6   f ; and a first vehicular air curtain device  130  (an example of a blower) configured to prevent dirt, such as a foreign object, from adhering to the front LiDAR  6   f . Hereinafter, a vehicular air curtain device is referred to as an air curtain device. 
     The front camera cleaner unit  109   a  includes: a second cleaner device  140  (an example of the washer) configured to wash off dirt, such as a foreign object, adhering to the front camera  6   c ; and a second air curtain device  150  (an example of the blower) configured to prevent dirt, such as a foreign object, from adhering to the front camera  6   c.    
     The rear LC  104  includes: a third cleaner device  160  (an example of the washer) configured to wash off dirt, such as a foreign object, adhering to the rear LiDAR  6   b ; and a third air curtain device  170  (an example of the blower) configured to prevent dirt, such as a foreign object, from adhering to the rear LiDAR  6   b.    
     The rear camera cleaner unit  109   b  includes: a fourth cleaner device  180  (an example of the washer) configured to wash off dirt, such as a foreign object, adhering to the rear camera  6   d ; and a fourth air curtain device  190  (an example of the blower) configured to prevent a foreign object from adhering to the rear camera  6   d.    
     The air curtain device is configured to produce an air curtain that prevents a foreign object, such as dust and a drop of water, from adhering to a cleaning object by continuously blowing air at a predetermined wind speed or a predetermined air flow rate to the cleaning object, for example, the external sensor  6  such as a vehicle lamp, a LiDAR, and a camera, the sensor cover, and the like to cause a constant air flow to flow constantly on a surface of the cleaning object. The predetermined wind speed or the predetermined air flow rate of the continuously blown air refers to a wind speed or an air flow rate at which the air curtain can be produced that prevents a foreign object from adhering to a cleaning surface  21  of the LiDAR  6   f . The predetermined wind speed and the predetermined air flow rate are adjusted according to a vehicle speed. When a vehicle speed is low, a wind speed is set to be low. When a vehicle speed is high, a wind speed is set to be high. 
     Each of the cleaner devices  120 ,  140 ,  160 , and  180  is provided with a cleaner control unit (not shown). Each of the air curtain devices  130 ,  150 ,  170 , and  190  is provided with an air curtain control unit (to be described later with reference to  FIG. 6 ). The cleaner control units and the air curtain control units are electrically connected to the integrative control unit  111 . The cleaner control units and the air curtain control units control operation of the cleaner devices  120 ,  140 ,  160 , and  180  and the air curtain devices  130 ,  150 ,  170 , and  190  based on control signals from the integrative control unit  111 . The integrative control unit  111  is electrically connected to the vehicle control unit  3 . 
     Although the cleaner control units, the air curtain control units, and the integrative control unit  111  are provided as separate components in the present embodiment, these control units may be integrated. In this case, the cleaner control units, the air curtain control units, and the integrative control unit  111  may be configured with a single electronic control unit. Although the vehicle control unit  3  and the integrative control unit  111  are provided as separate components in the present embodiment, the vehicle control unit  3  and the integrative control unit  111  may be integrated. In this case, the vehicle control unit  3  and the integrative control unit  111  may be configured with a single electronic control unit. 
     The cleaner system  100  shown in the drawings is equipped with sensors including various external sensors  6 , such as the front LiDAR  6   f  and the front camera  6   c . The cleaner system  100  may include: a cleaner device configured to remove a foreign object adhering to a sensor (not shown), such as a side camera configured to acquire an image of the side of the vehicle  1 ; or an air curtain device configured to prevent a foreign object from adhering to the sensor. 
     Next, with reference to  FIGS. 4 to 8 , the cleaning objects, the cleaner devices (washers) configured to eject cleaning liquid toward the cleaning objects, and the air curtain devices (blowers) configured to eject air (wind) toward the cleaning objects will be described in detail. 
       FIG. 4  shows: the front LiDAR  6   f , which is an example of the cleaning objects; the first cleaner device  120  configured to eject cleaning liquid to the front LiDAR  6   f ; and the first air curtain device  130  configured to eject air to the front LiDAR  6   f.    
     The cleaning surface  21  of the front LiDAR  6   f , which is a cleaning object, is formed into, for example, a rectangular shape (a long sideways rectangular shape in the present example). The first cleaner device  120  is configured to spray the cleaning liquid toward the cleaning surface  21  of the front LiDAR  6   f  from a liquid nozzle  121 . The first air curtain device  130  is configured to blow air to the cleaning surface  21  of the front LiDAR  6   f  from an air nozzle  136 . The air nozzle  136  of the first air curtain device  130  is disposed, for example, at a side (left side in the present example) of the front LiDAR  6   f.    
     The liquid nozzle  121  of the first cleaner device  120  is disposed facing the upper side  22  (an example of a first side) of the cleaning surface  21  of the front LiDAR  6   f . That is, the liquid nozzle  121  is preferably disposed facing the long side of the long sideways rectangle of the cleaning surface  21 . Although the liquid nozzle  121  may be disposed facing the lower side  23  (an example of the first side) of the cleaning surface  21 , water, mud, or the like may enter an opening of the liquid nozzle  121  in this case. Thus, the liquid nozzle  121  is preferably disposed facing the upper side  22 . 
     The air nozzle  136  of the first air curtain device  130  is disposed facing the left side  24  (an example of the second side), which is perpendicular to the upper side  22  of the cleaning surface  21  of the front LiDAR  6   f . That is, the air nozzle  136  is preferably disposed facing the short side of the long sideways rectangle of the cleaning surface  21 . The air nozzle  136  may be disposed facing the right side  25  of the cleaning surface  21 . 
     Since configurations of other cleaning objects and a cleaner device and an air curtain device for each of those cleaning objects are the same as those in  FIG. 4 , description thereof will be omitted. Those cleaning objects includes: the rear LiDAR  6   b , the right LiDAR  6   r , the left LiDAR  6   l , the front camera  6   c , and the rear camera  6   d , which are external sensors; the right headlamp  7   r  and the left headlamp  7   l , which are vehicle lamps; the front window lf; the rear window  1   b ; and the like. 
       FIG. 5  is a perspective view showing the first cleaner device  120 . As shown in  FIG. 5 , the first cleaner device  120  includes: a cylinder  122 ; a piston  123 ; and a pair of liquid nozzles  121  and  121 . 
     The cylinder  122  is formed into a cylindrical shape, and a coupling portion  124  is provided in the rear. A hose for supplying the cleaning liquid is connected to the coupling portion  124 . The hose is also connected to a cleaning liquid tank (not shown) configured to store the cleaning liquid. When the hose is connected to the coupling portion  124 , the cleaning liquid is supplied from the cleaning liquid tank into the cylinder  122 . 
     The piston  123  is slidably accommodated in the cylinder  122 , which has a cylindrical shape. The piston  123  can move forward and backward in a front-rear direction along an axis of the cylinder  122 . 
     The pair of left and right liquid nozzles  121  and  121  are provided around a tip of the piston  123 . The liquid nozzles  121  and  121  are each provided with an ejection port  125  for ejecting the cleaning liquid. The liquid nozzles  121  and  121  are configured to eject the cleaning liquid from the ejection ports  125  toward the cleaning surface  21  of the front LiDAR  6   f . Since the pair of liquid nozzles  121  and  121  are similar, the left liquid nozzle  121  will be described in the following. 
     The liquid nozzle  121  is a fluidic nozzle (fluidic oscillating nozzle). A fluidic nozzle is a nozzle configured to change an ejection direction of a fluid by causing the fluid flowing inside the nozzle to interfere. Since the liquid nozzle  121  is a fluidic nozzle, it is possible to eject the cleaning liquid at high pressure toward a wide range of the cleaning surface  21  of the front LiDAR  6   f . The liquid nozzle  121  may eject the cleaning liquid from the ejection port  125  without changing the ejection direction of the cleaning liquid. 
     Although two liquid nozzles  121  are provided in the present example, the present invention is not limited thereto. For example, at the upper side of the front LiDAR  6   f , three or more liquid nozzles  121  may be provided abreast or one liquid nozzle  121  may be provided. For example, the liquid nozzle  121  is preferably provided with a wide ejection port correspondingly to the long sideways rectangle of the cleaning surface  21 . If a plurality of ejection ports or a wide ejection port is provided, the cleaning liquid can spread to a long sideways rectangle cleaning surface, such as the cleaning surface  21 . 
       FIG. 6  is a view showing rotation of the liquid nozzles  121  in the first cleaner device  120 . As shown in  FIG. 6 , the liquid nozzles  121  are attached to nozzle holders  126 . The nozzle holders  126  are attached to the piston  123  being rotatable around an axis L extending in a left-right direction of the piston  123 . The liquid nozzles  121  are attached to the nozzle holders  126  being rotatable around an axis M perpendicular to the axis L. If the liquid nozzles  121  and the nozzle holders  126  are appropriately rotated, the ejection ports  125  of the liquid nozzles  121  can be aimed at appropriate positions in accordance with a relative position of the liquid nozzles  121  to the front LiDAR  6   f . Accordingly, it is possible to adjust positions of the liquid nozzles  121  to cause the cleaning liquid to hit the front LiDAR  6   f  appropriately. 
     The liquid nozzle  121  may be provided at only one side around the tip of the piston  123 . Three or more liquid nozzles  121  may be provided along the upper side  22  of the cleaning surface  21 . Alternatively, one liquid nozzle  121  may be provided at the tip of the piston  123 . In this case, it is preferable for the liquid nozzle  121  to include a wide ejection port correspondingly to the long sideways rectangle of the cleaning surface  21 . If a plurality of ejection ports or a wide ejection port is provided, the cleaning liquid can spread to long sideways rectangle of the cleaning surface, such as the cleaning surface  21 . 
       FIG. 7  is an exploded perspective view showing the first air curtain device  130 . As shown in  FIG. 7 , the first air curtain device  130  includes: an air blowing mechanism  137  including a housing  131  and an impeller  132 ; an air curtain motor  133  (an example of a first motor, which may be referred to as a motor); a frame  134 ; and a motor case  135 . 
     The impeller  132  of the air blowing mechanism  137  is rotatable around a rotation axis Ax by the air curtain motor  133 . The impeller  132  includes a disk-shaped plate  132   a  and a plurality of blades  132   b . The blades  132   b  is provided extending in a radial direction of the impeller  132  and forming an annular shape on the plate  132   a.    
     The housing  131  covers the impeller  132 . The housing  131  is divided into two sides along the rotation axis Ax of the impeller  132 . The housing  131  embraces a doughnut-shaped internal space, in which the impeller  132  is accommodated. The housing  131  includes: inlets  131   a  for inhaling air; and an outlet  131   b  for exhaling the inhaled air. 
     The inlets  131   a  are opened along the rotation axis Ax at positions corresponding to the blades  132   b  of the impeller  132 . The outlet  131   b  is opened in a direction intersecting with the rotation axis Ax of the impeller  132 . 
     When the impeller  132  is rotated, air inhaled from the inlets  131   a  is pressed against an internal circumferential surface  131   c  of the housing  131  by the blades  132   b . The air pressed is guided along the internal circumferential surface  131   c  of the housing  131  to the outlet  131   b . The air guided to the outlet  131   b  is exhaled from the outlet  131   b  to the outside of the first air curtain device  130 . That is, the air inhaled along the rotation axis Ax of the impeller  132  is pushed out in the radial direction by the blades  132   b  rotating, is pressed against the internal circumferential surface  131   c  of the housing  131 , and is exhaled to the outside of the first air curtain device  130  from the outlet  131   b , which is opened in the radial direction. The air exhaled to the outside from the outlet  131   b  is blown toward the cleaning surface  21  of the front LiDAR  6   f  from the air nozzle  136  (see  FIG. 4 ), which is attached to the outlet  131   b . When the impeller  132  having the blades  132   b  is rotated, air is continuously blown toward the cleaning surface  21 . The air blown toward the cleaning surface  21  flows along the cleaning surface  21 . 
     Dust approaching the cleaning surface  21  is carried away from the cleaning surface  21  by the airflow flowing along the cleaning surface  21  and does not adhere to the cleaning surface  21 . In this way, the first air curtain device  130  can prevent dust and the like from adhering to the cleaning surface  21 . 
     In addition to the example described above, a propeller fan, a multiblade fan, a turbo fan, a mixed flow fan, or the like may be adopted as the air blowing mechanism of the first air curtain device  130 . These non-positive displacement blowing devices can easily obtain a relatively large air flow rate. A positive displacement blowing device, such as a reciprocating compressor, a rotary screw compressor, a roots-type compressor, and a vane compressor, may be adopted as the air blowing mechanism of the first air curtain device  130 . The air blowing mechanism may be referred to as a blower, a pump, or the like as well as a fan. 
     In  FIGS. 4 and 5 , the cleaner device and the air curtain device for the front LiDAR  6   f  are shown. Cleaner devices and air curtain devices for other cleaning objects are similar, and thus description thereof will be omitted. Those cleaning objects include: the rear LiDAR  6   b , the right LiDAR  6   r , the left LiDAR  6   l , the front camera  6   c , and the rear camera  6   d , which are external sensors; and sensor covers of these external sensors. Those cleaning objects further include: the right headlamp  7   r  and a left headlamp  7   l , which are vehicle lamps; the front window  1   f  and the rear window  1   b , which are vehicle windows; and the like. 
       FIG. 8  is a schematic diagram showing the front LiDAR  6   f  and the first cleaner device  120  and the first air curtain device  130 , which are attached to the front LiDAR  6   f . As shown in  FIG. 8 , the first cleaner device  120  and the first air curtain device  130  are attached to the front LiDAR  6   f  with a bracket  310 . The bracket  310  is provided on, for example, a bumper, a grille, or the like of the vehicle  1 . 
     In a front view of the cleaning surface  21  of the front LiDAR  6   f , the first cleaner device  120  is disposed inside a swept region swept out by translating the upper side  22  to the outside of the cleaning surface  21 . That is, the first cleaner device  120  is disposed inside a region above the upper side  22  in the front view of the front LiDAR  6   f  not overlapping with the cleaning surface  21 . The first cleaner device  120  is disposed in a width region A of the upper side  22  in the front view of the front LiDAR  6   f  not protruding from the cleaning surface  21  in the left-right direction. 
     In the front view of the cleaning surface  21  of the front LiDAR  6   f , first air curtain device  130  including the air nozzle  136  is disposed inside a swept region swept out by translating the left side  24  to the outside of the cleaning surface  21 . That is, the first air curtain device  130  including the air nozzle  136  is disposed inside a region in the left side of the left side  24  in the front view of the font LiDAR  6   f  not overlapping with the cleaning surface  21 . The first air curtain device  130  including the air nozzle  136  is disposed in a height region B of the left side  24  in the front view of the front LiDAR  6   f  not protruding from the cleaning surface  21  in the upper-lower direction. 
     A direction C of the ejection port  125  of the liquid nozzle  121  and a direction D of an ejection port  139  of the air nozzle  136  are set such that an intersection angle θ between the direction C and the direction D is in a range of 70° to 110°. The intersection angle θ is preferably 90° as shown in  FIG. 8 . 
     The cleaning liquid ejected from the ejection port  125  and air ejected from the ejection port  139  widen as they go away from the ejection ports  125  and  139 . Therefore, for example, a center line of an ejection range of the cleaning liquid ejected from the liquid nozzle  121  and a center line of an ejection range of the air ejected from the air nozzle  136  may intersect with each other at 70° 110°. 
     Although the air curtain device has been described in which air is continuously and constantly ejected during operation in the above embodiment, the present invention is not limited thereto. For example, the first air curtain device  130  may be configured to eject high-pressure air toward the cleaning object intermittently. Dirt may adhere to the cleaning object even if air is continuously or intermittently ejected from the air nozzle  136  or when the cleaner system  100  is not operating. Therefore, for example, when it is determined that dirt adhered to the cleaning object or when an input from the driver for operating the first cleaner device  120  is received, the cleaning liquid is ejected from the first cleaner device  120  to the cleaning object to remove the dirt adhering to the cleaning object. 
     If ejection ports of the cleaning liquid and the high-pressure air are provided in the same nozzle, when the high-pressure air is ejected during the ejection of the cleaning liquid, the high-pressure air is ejected to the cleaning liquid at high speed, and thus the cleaning liquid may be foamed. 
     Therefore, the cleaner system  100  according to the present embodiment includes: the first cleaner device  120  (an example of the washer) configured to eject the cleaning liquid toward the front LiDAR  6   f  (an example of the cleaning objects) from the liquid nozzle  121 ; and the first air curtain device  130  (an example of the blower) configured to eject air toward the front LiDAR  6   f  from the air nozzle  136 . In the cleaner system  100 , the direction of the ejection port  125  of the liquid nozzle  121  and the direction of the ejection port  139  of the air nozzle  136  are perpendicular to each other. According to this configuration, if the direction of the ejection port  125  of the liquid nozzle  121  and the direction of the ejection port  139  of the air nozzle  136  are perpendicular to each other, the ejection port  125  of the liquid nozzle  121  and the ejection port  139  of the air nozzle  136  are arranged apart to a certain extent. Therefore, for example, even when air is ejected from the air nozzle  136  during the ejection of the cleaning liquid, the air is prevented from being ejected to the cleaning liquid at high speed. 
     Accordingly, it is possible to prevent the cleaning liquid from being foamed by the ejection of the air and to clean the cleaning object effectively. 
     According to the cleaner system  100 , on the long sideways rectangle of the cleaning surface  21  of the front LiDAR  6   f , the liquid nozzle  121  is disposed facing the upper side  22 , which is the long side of the cleaning surface  21 , and the air nozzle  136  is disposed facing the left side  24 , which is the short side of the cleaning surface  21 . According to this configuration, the ejection directions of the cleaning liquid and air can be set perpendicular to each other simply. Since the cleaning liquid is ejected to the long sideways rectangle of the cleaning surface  21  from above, the cleaning liquid can easily reach the cleaning surface  21  without resisting the gravity. Since air is continuously ejected to the long sideways rectangle of the cleaning surface  21  from the side, the air can be easily spread to the cleaning surface  21 . Accordingly, cleaning can be more effective. 
     According to the cleaner system  100 , the first cleaner device  120  and the first air curtain device  130  are attached to the front LiDAR  6   f  with the bracket  310 . According to this configuration, mountability of the first cleaner device  120  and the first air curtain device  130  to the cleaning object, such as the front LiDAR  6   f , is improved. In the front view of the cleaning surface  21 , the first cleaner device  120  is disposed inside a region swept out by translating the upper side  22  to the outside of the cleaning surface  21 . The first air curtain device  130  is disposed inside a region swept out by translating the left side  24  to the outside of the cleaning surface  21 . Accordingly, space can be saved. Good is mountability of the cleaner device and the air curtain device according to the configurations above particularly to a LiDAR out of the cleaning objects. 
     According to the cleaner system  100 , the first air curtain device  130  is configured to produce an air curtain and to send air continuously to the front LiDAR  6   f  at a predetermined wind speed or a predetermined air flow rate based on the operation signal output from the integrative control unit  111 . According to this configuration, it is possible to blow air continuously and widely to the front LiDAR  6   f  at a large air flow rate and to prevent dirt from adhering to the front LiDAR  6   f  effectively. 
     First Modification 
     Although the liquid nozzle  121  of the first cleaner device  120  is disposed facing the upper side  22 , which is the long side of the cleaning surface  21  of the front LiDAR  6   f , and the air nozzle  136  of the first air curtain device  130  is disposed facing the left side  24 , which is the short side of the cleaning surface  21  in the embodiment described above, the present invention is not limited thereto. 
       FIG. 9  is a diagram showing a first modification of attachment positions of the first cleaner device  120  and the first air curtain device  130  to the front LiDAR  6   f . As shown in  FIG. 9 , the air nozzle  136  of the first air curtain device  130  may be disposed facing the upper side  22 , which is the long side of the cleaning surface  21  of the front LiDAR  6   f , and the liquid nozzle  121  of the first cleaner device  120  may be disposed facing a right side  25  that is the short side of the cleaning surface  21 . In the front view of the cleaning surface  21  of the front LiDAR  6   f , a region in which the first cleaner device  120  and the first air curtain device  130  including the air nozzle  136  is similar to the embodiment described earlier. An intersection angle between the direction of the ejection port  125  of the liquid nozzle  121  and the direction of the ejection port  139  of the air nozzle  136  is also similar to the embodiment described earlier. 
     Second Modification 
       FIG. 10  is a diagram showing a second modification of attachment positions of the first cleaner device and the first air curtain device to the front LiDAR  6   f . As shown in  FIG. 10 , to the front LiDAR  6   f , a liquid nozzle  121 A of a first cleaner device  120 A may be disposed at a corner between the upper side  22  and the right side  25  of the cleaning surface  21 , and an air nozzle  136 A of a first air curtain device  130 A may be disposed at a corner between the upper side  22  and the left side  24  of the cleaning surface  21 . The arrangement of the first cleaner device  120 A and the first air curtain device  130 A may be reversed. According to this configuration, since an ejection port  125 A of the liquid nozzle  121 A and an ejection port  139 A of the air nozzle  136 A are arranged apart, it is possible to prevent air from being blown to the cleaning liquid at high speed. Accordingly, it is possible to prevent the cleaning liquid from being foamed by the ejection of the air similarly to the embodiment described earlier. 
     Third Modification 
     Although the directions of the ejection ports of the liquid nozzle and the air nozzle are set perpendicular to each other for a single cleaning object in the embodiment described earlier, the present invention is not limited thereto. 
       FIG. 11  is a perspective view showing a third modification in which directions of ejection ports of the liquid nozzle and the air nozzle are set perpendicular to each other for two cleaning objects arranged in parallel. As shown in  FIG. 11 , in a cleaner system according to the present example, a rear camera  210  and a reverse camera  220 , which are cleaning objects, are combinedly provided, and ejection ports of liquid nozzles  211  and  221  of a cleaner device and ejection ports of air nozzles  212  and  222  of an air curtain device are set perpendicular to each other for the cameras. 
     The rear camera  210  and the reverse camera  220  are attached to the rear of the vehicle  1 . The rear camera  210  is configured to acquire a relatively wide image of the rear side of the vehicle  1  continuously. For example, by the image from the rear camera  210 , it is possible to confirm whether there is another vehicle that will overtake the host vehicle from behind. The reverse camera  220  is configured to acquire a nearby image behind the host vehicle when the vehicle  1  moves backward. For example, by the image from the reverse camera  220 , it is possible to confirm whether there is an obstacle near the host vehicle during parking or the like. 
     The liquid nozzle  211  is provided above a lens  213  (cleaning surface) of the rear camera  210  and is configured to eject the cleaning liquid toward the lens  213 . The air nozzle  212  is provided at a right side of the lens  213  of the rear camera  210  and is configured to eject air toward the lens  213 . Directions of the ejection ports of the liquid nozzle  211  and the air nozzle  212  are set perpendicular to each other. An intersection angle between the directions of the ejection ports of the liquid nozzle  211  and the air nozzle  212  is in a range of 70° to 110°. The intersection angle is preferably 90°. The liquid nozzle  221  is provided at a right side of the lens  223  (cleaning surface) of the reverse camera  220  and is configured to eject the cleaning liquid toward the lens  223 . The air nozzle  222  is provided above the lens  223  of the reverse camera  220  and is configured to eject air toward the lens  223 . The directions of the ejection ports of the liquid nozzle  221  and the air nozzle  222  are set perpendicular to each other. An intersection angle between the directions of the ejection ports of the liquid nozzle  221  and the air nozzle  222  is in a range of 70° to 110°. The intersection angle is preferably 90°. 
     According to the cleaner systems according to the first to third modifications, even when air is ejected from the air nozzles  136 ,  136 A,  212 , and  222  during the ejection of the cleaning liquid, it is possible to prevent the cleaning liquid from being foamed by the ejection of the air. Accordingly, the cleaning objects can be effectively cleaned similarly to the cleaner system  100  according to the embodiment described earlier. 
     Second Embodiment 
       FIG. 12  is a timing chart showing a relationship among an air curtain operation signal, a washer operation signal, an air curtain operation state, and a cleaner operation state of a cleaner system  100 A according to a second embodiment. 
     The air curtain operation signal shown in  FIG. 12  is for operating an air curtain device. For example, the air curtain operation signal is transmitted from the integrative control unit  111  to an air curtain control unit of the first air curtain device  130 . The washer operation signal is for operating a cleaner device. For example, the washer operation signal is transmitted from the integrative control unit  111  to a cleaner control unit of the first cleaner device  120 . 
     The air curtain control unit of the first air curtain device  130  operates the air curtain motor  133  of the first air curtain device  130  based on an input of the air curtain operation signal. The air curtain motor  133  is operated to continuously blow air at a predetermined wind speed toward the cleaning surface  21  of the front LiDAR  6   f  from the air nozzle  136 . The air curtain operation signal is transmitted from the integrative control unit  111 , for example, when an ignition switch of the vehicle  1  is turned on or when a switch for operating the air curtain device is operated by the driver. 
     The cleaner control unit of the first cleaner device  120  operates a washer motor (an example of a second motor, not shown) of the first cleaner device  120  based on an input of the washer operation signal. The washer motor is operated to eject the cleaning liquid toward the cleaning surface  21  of the front LiDAR  6   f  from the liquid nozzle  121 . The washer operation signal is transmitted from the integrative control unit  111 , for example, when a switch for operating a cleaner device is operated by the driver. The washer operation signal is transmitted, for example, when dirt is detected by a dirt sensor configured to detect dirt on the cleaning surface  21  of the front LiDAR  6   f  or when dirt on the cleaning surface  21  is detected based on vehicle surrounding information acquired by the front LiDAR  6   f . Further, the washer operation signal is transmitted, for example, when the self-driving mode is started, when bad weather is detected by a weather sensor, when a temperature decrease is detected by a thermometer, when a speed increase is detected by a vehicle speed sensor, when it is detected that the vehicle  1  enters expressway according to traffic information from a Japan Road Traffic Information Center (JARTIC). 
     Signals such as an on signal of the ignition switch, an on signal of the switch for operating an air curtain device and the like, and a detection signal of the dirt sensor are input into the vehicle control unit  3  and then input into the integrative control unit  111  via the vehicle control unit  3 . The integrative control unit  111  transmits the air curtain operation signals and the washer operation signals based on these signals input via the vehicle control unit  3 . 
     A vertical axis of the air curtain operation state shown in  FIG. 12  indicates a wind speed V of air ejected from the first air curtain device  130 . The washer operation state shown in  FIG. 12  indicates whether the cleaning liquid is ejected from the liquid nozzle  121  (in an operation state) or not (in a stop state). The vertical axis of the air curtain operation state may indicate an air flow rate of the air ejected from the first air curtain device  130 . 
     As shown in  FIG. 12 , when an air curtain operation signal  201  is output, the air curtain motor  133  is driven to start blowing air from the air nozzle  136  of the first air curtain device  130 . The air ejected from the air nozzle  136  is, for example, ejected continuously at a predetermined wind speed V  1 . In the air curtain operation state in  FIG. 12 , it takes a time tl for a wind speed to reach V 1  from a start of the ejection of the air due to response characteristics of rotation of the impeller  132  to the rotation of the air curtain motor  133 . 
     When a washer operation signal  202  is output during operation of the first air curtain device  130  (in this example, a state in which a wind speed is V 1 ), the washer motor is driven to eject the cleaning liquid from the liquid nozzle  121  of the first cleaner device  120 . The integrative control unit  111  performs control such that the ejection of the cleaning liquid from the liquid nozzle  121  is started when a time t 2  has passed since the washer operation signal  202  rose. Ejection duration of the cleaning liquid from the liquid nozzle  121  is set to, for example, a predetermined time t 3 . 
     In this way, when the washer operation signal  202  is output during the operation of the first air curtain device  130  (in this example, a state in which a wind speed of ejected air is V 1 ), the integrative control unit  111  reduces a wind speed of the air ejected from the air nozzle  136 . Specifically, as shown in  FIG. 12 , a wind speed is reduced from the wind speed V 1  to a wind speed V 2 . The integrative control unit  111  performs control such that the reduction in a wind speed of the air ejected from the air nozzle  136  is earlier than the cleaning liquid is ejected from the liquid nozzle  121  based on the washer operation signal  202 . Specifically, in the present example, a start of the reduction in a wind speed of the air ejected from the air nozzle  136  is the time t 2  earlier than the cleaning liquid is ejected from the liquid nozzle  121 . 
     The time t 2  corresponds to a time that it takes for a wind speed of the air ejected from the air nozzle  136  to be reduced from the wind speed V 1  to the wind speed V 2  due to the response characteristics of rotation of the impeller  132  to the rotation of the air curtain motor  133 . The time t 2  can be changed, for example, by controlling a drive voltage or a drive current of the air curtain motor  133 . 
     The integrative control unit  111  performs control such that duration of the reduction in a wind speed of the air ejected from the air nozzle  136  is equal to or longer than duration of the ejection of the cleaning liquid from the liquid nozzle  121 . In the present example, the duration of the reduction in a wind speed of the air ejected from the air nozzle  136  to the wind speed V 2  is equal to the time t 3  during which the cleaning liquid is ejected from the liquid nozzle  121 . When the time t 3  during which the cleaning liquid is ejected has passed, the integrative control unit  111  performs control such that a wind speed of the air ejected from the air nozzle  136  is increased from the wind speed V 2  to the wind speed V 1  after the ejection of the cleaning liquid from the liquid nozzle  121  is stopped. That is, in the present example, a wind speed is increased to the wind speed V 1  when the time t 3  has passed since the air started to be ejected at the wind speed V 2 . 
     As described above, the cleaner system  100 A according to the second embodiment includes: the first cleaner device  120  configured to eject the cleaning liquid toward the front LiDAR  6   f  from the liquid nozzle  121 ; the first air curtain device  130  configured to continuously sends air to the front LiDAR  6   f  at a predetermined wind speed from the air nozzle  136  to prevents dirt from adhering to the front LiDAR  6   f ; and the integrative control unit  111  configured to control the first cleaner device  120  and the first air curtain device  130 . The integrative control unit  111  is configured to control the first air curtain device  130  to reduce a wind speed of the air ejected from the air nozzle  136  while the cleaning liquid is being ejected from the liquid nozzle  121 . According to this configuration, it is possible to prevent a foreign object from adhering to the front LiDAR  6   f  by an air curtain formed by an air ejected from the air nozzle  163  and to wash off an adhering foreign object with the cleaning liquid. In addition, it is possible to prevent an adverse effect of the air curtain, such as a problem that the cleaning liquid is foamed by the air continuously blown above a certain wind speed (air flow rate) during the ejection of the cleaning liquid and the foam from accumulating in the ejection port  125  of the liquid nozzle  121 . Accordingly, it is possible to maintain ejection performance of the cleaning liquid. 
     The integrative control unit  111  starts to reduce a wind speed of the air ejected from the air nozzle  136  before the cleaning liquid is ejected from the liquid nozzle  121 . According to this configuration, it is possible to more reliably prevent an adverse effect of the air curtain on the ejected cleaning liquid (for example, foaming of the cleaning liquid). 
     Third Embodiment 
       FIG. 13  is a timing chart showing a relationship among an air curtain operation signal, a washer operation signal, an air curtain operation state, and a cleaner operation state of a cleaner system  100 B according to a third embodiment. 
     A power supply of the air curtain motor  133  shown in  FIG. 13  indicates whether power is supplied to the air curtain motor  133  (in a power supply state) or not (in a power cutoff state). Similarly, a power supply of the washer motor indicates whether power is supplied to the washer motor. Other items in  FIG. 13  are similar to the second embodiment. 
     As shown in  FIG. 13 , when the air curtain operation signal  201  is output, power is supplied to the air curtain motor  133 , and air is started to be blown from the air nozzle  136  of the first air curtain device  130 . The air is ejected from the air nozzle  136 , for example, continuously at a predetermined wind speed V 1  . Similarly to the time tl in the second embodiment, a time t 4 , which it takes for a wind speed to reach V 1  from a start of the blowing in the air curtain operation state in  FIG. 13 , is due to the response characteristics of the impeller  132 . 
     When the washer operation signal  202  is output during operation of the first air curtain device  130  (in the present example, a state in which a wind speed of the ejected air is V 1 ), power is supplied to the washer motor, and the cleaning liquid is ejected from the liquid nozzle  121  of the first cleaner device  120 . The integrative control unit  111  performs control such that the power supply to the washer motor is started when a time t 5  has passed since the washer operation signal  202  rose. Ejection duration of the cleaning liquid from the liquid nozzle  121  is set to, for example, a predetermined time t 6 . 
     In this way, when the washer operation signal  202  is output during the operation of the first air curtain device  130  (in this example, in a state in which a wind speed of the ejected air is V 1 ), the integrative control unit  111  stops the power supply to the air curtain motor  133 . As a result, a wind speed of the air ejected from the air nozzle  136  is zero. The integrative control unit  111  performs control such that the cutoff of the power supply to the air curtain motor  133  is earlier than power is supplied to the washer motor based on the washer operation signal  202 . In the present example, that the cutoff of the power supply to the air curtain motor  133  is the time t 5  earlier than the power supply to the washer motor is started based on the washer operation signal  202 . 
     Duration of the cutoff of the power supply to the air curtain motor  133  is set to, for example, a predetermined time t 7 . The integrative control unit  111  is configured to resume the power supply to the air curtain motor  133  when the time t 7  during which power supply is stopped has passed. In the present example, the power supply to the air curtain motor  133  is resumed when the time t 7  has passed since the washer operation signal  202  was output (rising of the washer operation signal  202 ). When the power supply to the air curtain motor  133  is resumed, air is started to be ejected from the air nozzle  136 , and the air is continuously ejected at the wind speed V 1 . 
     The time t 7 , which it takes for the power supply to the air curtain motor  133  to be resumed, is set to be equal to or longer than a time obtained by adding the time t 5 , which it takes for a wind speed of the air ejected from the air nozzle  136  to be zero from the output of the washer operation signal  202 , to the time t 6 , during which the cleaning liquid is being ejected. In the present example, the time t 7  is set to be equal to the time obtained by adding the time t 5  to the time t 6 . Therefore, in the present example, while the cleaning liquid is being ejected, blowing from the air nozzle  136  is stopped, that is, a wind speed is set to zero. 
     As described above, the integrative control unit  111  of the cleaner system  100 B according to the third embodiment is configured to stop the power supply to the air curtain motor  133  configured to drive the first air curtain device  130  based on the washer operation signal  202  for operating the first cleaner device  120 . According to this configuration, similarly to the cleaner system  100 A according to the second embodiment, it is possible to prevent an adverse effect of the air curtain during the ejection of the cleaning liquid and to maintain the ejection performance of the cleaning liquid. 
     The integrative control unit  111  of the cleaner system  100 B is configured to stop, based on the washer operation signal  202 , the power supply to the air curtain motor  133  of the first air curtain device  130  before the power supply to the washer motor configured to drive the first cleaner device  120  is started. Accordingly, it is possible to more reliably curb the adverse effect of the air curtain during the ejection of the cleaning liquid. 
     The integrative control unit  111  of the cleaner system  100 B is configured to resume the power supply to the air curtain motor  133  when a predetermined time (time t 7 ) has passed since the washer operation signal  202  was received. According to this configuration, it is possible to easily resume the blowing by the first air curtain device  130  and to more effectively prevent a foreign object from adhering to the front LiDAR  6   f  by resuming operation of the air curtain after an adhering foreign object is washed off with the cleaning liquid. 
     According to the cleaner system  100 B, the predetermined time (time t 7 ), which it takes for the power supply to the air curtain motor  133  to be resumed, is set to be equal to or longer than the time obtained by adding the time (time t 5 ) that it takes for the first air curtain device  130  to stop from receipt of the washer operation signal  202 , to a time (time t 6 ) during which the cleaning liquid is being ejected. Therefore, the blowing from the air nozzle  136  is stopped at least while the cleaning liquid is being ejected, and thus it is possible to minimize the adverse effect of the air curtain during the ejection of the cleaning liquid. In addition, since the blowing is resumed after the cleaning liquid is ejected, it is possible to prevent a foreign object from adhering to the cleaning surface  21  by the air curtain effectively. 
     Fourth Embodiment 
     Next, a function of an air curtain device according to a fourth embodiment will be described in detail with reference to  FIG. 14 .  FIG. 14  is a block diagram showing a first air curtain device  130 . As shown in  FIG. 14 , the first air curtain device  130  includes: an air blowing mechanism  137 ; a motor  133  configured to drive the air blowing mechanism  137 ; and an air curtain control unit  138  configured to control the motor  133  in accordance with a predetermined condition. 
     To the vehicle control unit  3 , a vehicle speed sensor  31  is connected. To the vehicle control unit  3 , rain sensor  32  configured to detect whether it is raining around the host vehicle; a hygrometer  34  configured to measure humidity around the host vehicle; a thermometer  35  configured to measure a temperature around the host vehicle; a camera  36  configured to acquire an image around the host vehicle (including, for example, the front camera  6   c , the rear camera  6   d , a side camera, and the like); and the like are further connected. To the vehicle control unit  3 , a wiper operator  33 , which is an input unit of the HMI  8 , is further connected. To the vehicle control unit  3 , a wireless communication unit  10  configured to acquire weather information about surroundings of the host vehicle from an external infrastructure device is further connected. 
     The camera  36  may be connected to the integrative control unit  111 . For example, a signal for notifying whether each camera can normally acquire an image around the host vehicle is input from the camera  36  to the integrative control unit  111 . A signal indicating that an image cannot be normally acquired due to a foreign object adhering to the camera or another signal indicating that an image can be normally acquired may be input instead into the integrative control unit  111 . 
     Information detected by the sensors  31 ,  32 ,  34 ,  35 , and  36  and information output from the wiper operator  33  are input into the integrative control unit  111  via the vehicle control unit  3 . As for “input via the vehicle control unit  3 ,” information may be input into the integrative control unit  111  without being processed by the vehicle control unit  3 , or information that is different from information from the sensors  31 ,  32 ,  34 ,  35 , and  36  or information from the wiper operator  33  may be input into the integrative control unit  111  after the vehicle control unit  3  perform some processing based on information acquired by the vehicle control unit  3  from the sensors  31 ,  32 ,  34 ,  35 , and  36  and information acquired by the vehicle control unit  3  from the wiper operator  33 . The integrative control unit  111  generates an operation signal for operating the first air curtain device  130  based on the input information and transmits the generated operation signal to the air curtain control unit  138 . The air curtain control unit  138  controls the operation of the motor  133  based on the operation signal output from the integrative control unit  111 . 
     In the following, a case will be described in which the first air curtain device  130  is operated based on vehicle speed information detected by the vehicle speed sensor  31 . 
     When an ignition switch is operated and an ignition on signal is input into the vehicle control unit  3 , the vehicle control unit  3  transmits vehicle speed information output from the vehicle speed sensor  31  to the integrative control unit  111 . The integrative control unit  111  sets a wind speed of the air continuously blown from the air nozzle  136  of the first air curtain device  130  toward the cleaning surface  21  of the front LiDAR  6   f  based on the input vehicle speed information. 
     The set wind speed refers to a wind speed at which an air curtain for preventing a foreign object, such as dust and a drop of water, from adhering to the cleaning surface  21  of the front LiDAR  6   f  can be produced. Therefore, the set wind speed is changed in accordance with a vehicle speed. When a vehicle speed is low, the set wind speed is low. When a vehicle speed is high, the set wind speed is high. For example, the setting of a wind speed may be performed continuously in accordance with the vehicle speed information input continuously or may be performed at a predetermined cycle. 
     The integrative control unit  111  transmits an operation signal for blowing air at the set wind speed to the air curtain control unit  138  of the first air curtain device  130 . The air curtain control unit  138  controls the motor  133  so as to blow air at the set wind speed based on the input operation signal. 
     Although a wind speed is set in accordance with a vehicle speed in the present example, the present invention is not limited thereto. For example, the air curtain control unit  138  may set an air flow rate according to a vehicle speed. The air curtain control unit  138  may set a drive voltage or a drive current of the motor  133  in accordance with a vehicle speed. The drive voltage or the drive current of the motor  133  may set a wind speed or an air flow rate of air output from the air curtain device. If a brushless motor is used as the motor  133 , the air curtain control unit  138  controls the brushless motor by pulse-width modulation (PWM) control. For example, the air curtain control unit  138  can control a duty cycle in accordance with a vehicle speed and control a wind speed or an air flow rate of the air output from the air curtain device. Operation of the first air curtain device  130  has been described in the present example, and other air curtain devices are operated similarly. 
     Considering the operation of the air curtain device described above, the inventors found that a minimum wind speed or the like required to produce the air curtain depends on circumstances. For example, when a vehicle speed is fast, it is necessary to increase a wind speed of the air blown from the air curtain device in order to produce an air curtain to protect a cleaning object from dust mixed with the air blown toward the cleaning object. On the contrary, when a vehicle speed is slow, an air curtain can be produced even when a wind speed of the air blown from the air curtain device is slow. 
     Since the air curtain device is required to continuously operate, minimizing power consumption of the air curtain device is preferable. In particular, a self-driving car is equipped with many external sensors and thus, many cleaning objects, thereby the number of air curtain devices mounted on the vehicle being great. 
     Therefore, the inventors considered how to reduce the power consumption of the air curtain device with a minimum function of preventing a foreign object from adhering to a cleaning object maintained. 
     Therefore, according to the first air curtain device  130  in the present embodiment, a wind speed and an air flow rate of the air blown toward the cleaning object or the drive voltage and the drive current of the motor are set according to a vehicle speed. Therefore, it is possible to operate the first air curtain device  130  with a wind speed, an air flow rate, the drive voltage, and the drive current set minimum for maintaining the air curtain in accordance with traveling circumstances (traveling speed). As a result, the power consumption of the first air curtain device  130  can be reduced. Accordingly, even if the number of cleaning objects (such as sensors) and the number of air curtain devices mounted on the vehicle is great, the power consumption of the cleaner system  100  equipped with the air curtain devices can be reduced. 
       FIG. 15  is a side view showing the rear of the vehicle  1 . As shown in  FIG. 15 , the rear LiDAR  6   b  and the rear camera  6   d  are attached to the rear of the vehicle  1  as the cleaning objects. 
     The rear LiDAR  6   b  and the rear camera  6   d  are attached at a relatively low position, for example, about 850 mm from a ground G. In general, during traveling of the vehicle  1 , dust on the ground G is less prone to be whirled up when the vehicle  1  travels at low speed and is prone to be whirled up when the vehicle  1  travels at high speed. Therefore, when the vehicle  1  travels at low speed (for example, 60 km/h or less), dust is less prone to adhere to the rear LiDAR  6   b  and the rear camera  6   d . On the other hand, when the vehicle  1  travels at high speed (for example, 80 km/h or more), an airflow flowing on a surface of a vehicle body is detached in the rear of the vehicle to lower a (static) pressure, thereby air flowing around the rear LiDAR  6   b  and the rear camera  6   d  from surroundings including the ground G. Head laminar flow on a surface of the vehicle may be detached around the rear LiDAR  6   b  and the rear camera  6   d  to produce turbulent flow, thereby air flowing around the rear LiDAR  6   b  and the rear camera  6   d  from surroundings including the ground G. Therefore, during high-speed traveling of the vehicle  1 , since dust is carried by the airflow, dust is prone to adhere to the rear LiDAR  6   b  and the rear camera  6   d.    
     According to the third air curtain device  130 , the fourth air curtain device  190 , and the cleaner system  100  according to the present embodiment, since air can be blown toward the rear LiDAR  6   b  and the rear camera  6   d  at a suitable wind speed corresponding to a vehicle speed, it is possible to prevent dust whirled up from the ground G from adhering to the rear camera and the rear LiDAR. 
     For example, when a vehicle speed is 60 km/h or less, the third curtain device  170  and fourth air curtain device  190  are operated at a first wind speed. When a vehicle speed is higher than 60 km/h and is 80 km/h or less, the third curtain device  170  and fourth air curtain device  190  are operated at a second wind speed higher than the first wind speed. When a vehicle speed exceeds 80 km/h, the third curtain device  170  and fourth air curtain device  190  are operated at a third wind speed higher than the second wind speed. 
     The vehicle control unit  3  may output the vehicle speed information acquired from the vehicle speed sensor  31  to the air curtain control unit  138  or may output, to the air curtain control unit, instructions for the vehicle control unit  3  to operate the air curtain devices  170  and  190  at one of the first, second, and third wind speeds according to a vehicle speed. 
     Although a wind speed or the like of the air blown to a cleaning object is continuously changed according to a traveling speed (vehicle speed) of the vehicle  1  soon after an ignition on signal is input to operate the air curtain device in the fourth embodiment, the present invention is not limited thereto. For example, when the ignition on signal is input to operate the air curtain device, the air curtain device may be operated to blow air at a predetermined wind speed set in advance until a vehicle speed exceeds a threshold, and then a wind speed or the like of the air may be changed according to a vehicle speed. 
     For example, in the cleaner system  100  shown in  FIG. 3 , operation of each air curtain device may be started at different times. For example, the first air curtain device  130  to clean the front LiDAR  6   f  and the second air curtain device  150  to clean the front camera  6   c  may be started soon after the ignition on signal is input, and the third air curtain device  170  to clean the rear LiDAR  6   b  and the fourth air curtain device  190  to clean the rear camera  6   d  may be started as necessary (for example, when a vehicle speed exceeds a threshold). 
     Although an operation signal for operating the first air curtain device  130  is generated by the integrative control unit  111  based on the information output from the sensors  31 ,  32 ,  34 ,  35 , and  36  and the information output from the wiper operator  33  in the fourth embodiment, the present invention is not limited thereto. The operation signal may be generated, for example, by the vehicle control unit  3 . In this case, the vehicle control unit  3  transmits the generated operation signal to the air curtain control unit  138  via the integrative control unit  111 . The air curtain control unit  138  controls operation of the motor  133  based on the operation signal output from the vehicle control unit  3 . 
     For example, when an ignition switch is operated and an ignition on signal is input to the vehicle control unit  3 , the vehicle control unit  3  generates an operation signal for operating the first air curtain device  130  based on information output from the sensors  31 ,  32 ,  34 ,  35 , and  36  and information output from the wiper operator  33 . The vehicle control unit  3  transmits the generated operation signal to the integrative control unit  111 . The integrative control unit  111  transmits the operation signal output from the vehicle control unit  3  to the air curtain control unit  138  without processing the operation signal. The air curtain control unit  138  controls the operation of the motor  133  based on the operation signal input into the air curtain control unit  138  via the integrative control unit  111 . 
     Although the integrative control unit  111  and the air curtain control unit  138  are provided as separate components in the fourth embodiment, the integrative control unit  111  and the air curtain control unit  138  may be integrated. 
     Although the air curtain device is included in the cleaner system  100  in the fourth embodiment, the present invention is not limited thereto. For example, the air curtain device and the cleaner device may be mounted on the vehicle  1  independently. Alternatively, only the air curtain device may be mounted on the vehicle  1 . In these cases, the air curtain control unit of the air curtain device is configured to directly acquire, from the vehicle control unit  3 , an operation signal generated based on the information output from the sensors  31 ,  32 ,  34 ,  35 , and  36  and the information output from the wiper operator  33 . 
     Although air is continuously blown toward the cleaning object from the air curtain device in the fourth embodiment, the present invention is not limited thereto. Dirt may adhere to the cleaning object even if air is continuously ejected from the air nozzle  136  or when the cleaner system  100  is not operating. Therefore, for example, when it is determined that dirt adhered to the cleaning object and the cleaning liquid is ejected from the first cleaner device  120  toward the cleaning object, the cleaning objects are cleaned by the cleaner devices  120 ,  140 ,  160 , and  180 . At this time, the first air curtain device  130  may be configured to intermittently eject high-pressure air toward the cleaning object. 
     Although the air curtain device is operated based on the vehicle speed information detected by the vehicle speed sensor  31  in the fourth embodiment, the present invention is not limited thereto. The air curtain device may be operated, for example, based on a detection result of the rain sensor  32  configured to detect whether it is raining around the host vehicle. 
     The integrative control unit  111  sets a wind speed of the air continuously blown from the air nozzle  136  of the first air curtain device  130  toward the cleaning surface  21  of the front LiDAR  6   f  based on the detection result output from the rain sensor  32 . For example, when it is detected that it is raining around the host vehicle, the integrative control unit  111  sets a wind speed of the air blown from the first air curtain device  130  toward the front LiDAR  6   f  for V 1  in order to prevent a drop of rain from adhering to the front LiDAR  6   f . When it is detected that it is not raining around the host vehicle, the integrative control unit  111  sets a wind speed of the air blown from the first air curtain device  130  toward the front LiDAR  6   f  for V 2 , which is lower than V 1 , in order to prevent dust from adhering to the front LiDAR  6   f.    
     The integrative control unit  111  transmits an operation signal for blowing air at a set wind speed to the air curtain control unit  138  of the first air curtain device  130 . The air curtain control unit  138  controls the motor  133  to blow air at the set wind speed based on the input operation signal. 
     The air curtain device may be operated based on, for example, a wiper operation signal output from the wiper operator  33 . 
     The integrative control unit  111  sets a wind speed of the air continuously blown from the air nozzle  136  of the first air curtain device  130  toward the cleaning surface  21  of the front LiDAR  6   f  based on a signal output from the wiper operator  33 . For example, when the wiper operation signal is output indicating that a wiper is operating, the integrative control unit  111  determines that it is raining around the host vehicle to set a wind speed of the air blown from the first air curtain device  130  toward the front LiDAR  6   f  for V 1  similarly to the case of the rain sensor  32 . When the wiper operation signal is not output, the integrative control unit  111  determines that it is not raining around the host vehicle to set a wind speed of the air blown from the first air curtain device  130  toward the front LiDAR  6   f  for V 2 , which is lower than V 1 , similarly to the case of the rain sensor  32 . The processing after the integrative control unit  111  transmits the operation signal to the air curtain control unit  138  is similar to the case of the rain sensor  32 . 
     The air curtain device may be operated, for example, based on weather information acquired by the wireless communication unit  10 . 
     The integrative control unit  111  determines whether it is raining around the host vehicle based on the weather information received from an infrastructure facility to set a wind speed of the air continuously blown from the air nozzle  136  of the first air curtain device  130  toward the cleaning surface  21  of the front LiDAR  6   f . The processing performed by the integrative control unit  111  and the like when the weather information is acquired indicating that it is raining or not raining around the host vehicle is similar to the processing when the rain sensor  32  detects that it is raining or not raining around the host vehicle. 
     The air curtain device may be operated, for example, based on an image acquired by the camera  36 . 
     The integrative control unit  111  determines whether it is raining or snowing based on analysis of an image around the vehicle captured by the camera  36  to set a wind speed of the air continuously blown from the air nozzle  136  of the first air curtain device  130  toward the cleaning surface  21  of the front LiDAR  6   f . The processing performed by the integrative control unit  111  and the like when it is determined that it is raining or snowing is similar to the processing when the rain sensor  32  detects that it is raining around the host vehicle. The processing performed by the integrative control unit  111  and the like when it is determined that it is neither raining nor snowing is similar to the processing when the rain sensor  32  detects that it is not raining. 
     If snow adhered to the cleaning surface  21  of the front LiDAR  6   f , the adhering snow may not be removed, for example, by ejecting the cleaning liquid from the first cleaner device  120 . Reliably preventing snow from adhering to the cleaning surface  21  is preferable when it is snowing. Therefore, when it is determined that it is snowing based on analysis of the image around the vehicle, a wind speed of the air blown from the first air curtain device  130  toward the front LiDAR  6   f  may be set for the wind speed V 3 , which is higher than the wind speed V 1 , which is set when it is determined that it is raining. 
     The air curtain device may be operated, for example, based on detection results of the hygrometer  34  and the thermometer  35 . 
     The integrative control unit  111  determines whether it is snowing based on humidity detected by the hygrometer  34  and a temperature detected by the thermometer  35  to set a wind speed of the air continuously blown from the air nozzle  136  of the first air curtain device  130  toward the cleaning surface  21  of the front LiDAR  6   f . For example, when humidity is higher than a predetermined value and a temperature is lower than a predetermined value, that is, when it is determined that it is snowing, a wind speed of the air blown toward the front LiDAR  6   f  may be set for the wind speed V 3 , which is higher than the wind speed V 1 , which is set when it is raining, similarly to the case in which it is determined that it is snowing based on analysis of the image around the vehicle. The wiper operation signal output from the wiper operator  33  may be used instead of the hygrometer  34 , and it may be determined whether it is snowing based on the wiper operation signal and the thermometer  35 . 
     As described above, when the air curtain device is operated based on the outputs of the rain sensor  32 , the wiper operator  33 , the wireless communication unit  10 , the camera  36 , the hygrometer  34 , and the thermometer  35 , the air curtain device can be operated with a minimum wind speed, a minimum air flow rate, a minimum drive voltage, and a minimum drive current for maintaining the air curtain in accordance with traveling circumstances. Accordingly, the power consumption can be reduced. 
     Further, the cleaner system may include an air curtain switch (manual switch) for operating the air curtain device as an input unit of the HMI  8 . The integrative control unit  111  may generate an operation signal for operating the air curtain device based on an air curtain on signal output from the air curtain switch to transmit the generated operation signal to the air curtain control unit  138 . 
     Fifth Embodiment 
       FIG. 16  is a block diagram showing an air curtain system  100 C according to a fifth embodiment. The air curtain system  100 C includes: an information acquisition unit  30  configured to acquire weather information; the cleaners  101  to  109   b  described above; and an integrative control unit  111  configured to control the cleaners  101  to  109   b . In  FIG. 16 , out of the cleaners  101  to  109   b  described above, the front LC  103 , the front camera cleaner unit  109   a , the rear LC  104 , and the rear camera cleaner unit  109   b  are shown, and the front WW  101 , the rear WW  102 , the right LC  105 , the left LC  106 , the right HC  107 , and the left HC  108  are not shown. 
     The information acquisition unit  30  is, for example, thermometer configured to measure a temperature around the host vehicle, a hygrometer configured to measure humidity around the host vehicle, a rain sensor configured to detect whether it is raining around the host vehicle, a camera configured to acquire an image around the host vehicle, a LiDAR configured to detect a shape, a material, a color, or the like of an object, or the like. The information acquisition unit  30  is the wireless communication unit  10  configured to acquire information about weather around the host vehicle. As described above, the information acquisition unit  30  corresponds to the external sensor  6 , the wireless communication unit  10 , or the like shown in  FIG. 2 . In addition, the information acquisition unit  30  may be a wiper operation receiving unit configured to acquire a signal indicating that the wiper is operating. When the driver determines that the weather is bad, or it is raining or snowing, the driver operate the wiper operator. Thus, the information acquisition unit  30  acquires, as information indicating bad weather, a signal output when the wiper operator is operated or a signal indicating that the wiper is operating. The vehicle control unit  3  may automatically operate the wiper according to output of the camera, the rain sensor, or the like. The information acquisition unit  30  acquires a signal indicating that the wiper is operating when the vehicle control unit  3  operates the wiper. The information acquisition unit  30  is electrically connected to the integrative control unit  111  and the vehicle control unit  3 . 
     In the present embodiment, the vehicle control unit  3  transmits the weather information acquired by the information acquisition unit  30  to the integrative control unit  111 . The integrative control unit  111  may be electrically connected to the information acquisition unit  30 . In this case, the integrative control unit  111  may control operation of the front LC  103 , the front camera cleaner unit  109   a , the rear LC  104 , and the rear camera cleaner unit  109   b  based on the weather information acquired by the information acquisition unit  30 . 
     The air curtain system  100 C shown in  FIG. 16  is equipped with various external sensors, such as the front LiDAR  6   f  and the front camera  6   c . The air curtain system  100 C may include: a cleaner device configured to remove a foreign object from a sensor (not shown), such as a side camera configured to acquire an image of the side of the vehicle  1 ; and an air curtain device configured to prevent a foreign object from adhering to the sensor. 
     Next, a function of the air curtain device provided in the air curtain system  100 C will be described in detail.  FIG. 17  is a block diagram showing the first air curtain device  130 . As shown in  FIG. 17 , the first air curtain device  130  includes: the air blowing mechanism  137 ; the motor  133  configured to drive the air blowing mechanism  137 ; and the air curtain control unit  138  configured to control the motor  133  in accordance with a predetermined condition. 
     The air curtain control unit  138  is connected to the integrative control unit  111 . The integrative control unit  111  is connected to the vehicle control unit  3 . To the vehicle control unit  3 , the rain sensor  32 , the hygrometer  34 , a wiper operation receiving unit  37 , the thermometer  35 , the camera  36  (including, for example, the front camera  6   c , the rear camera  6   d , the side camera, and the like), the wireless communication unit  10 , and the like configured to acquire weather information are connected. 
     The camera  36  configured to acquire an image around the host vehicle may be connected to the integrative control unit  111 . For example, a signal for notifying whether each camera can normally acquire an image around the host vehicle is input from the camera  36  into the integrative control unit  111 . A signal indicating that an image cannot be normally acquired due to a foreign object, such as ice (snow), mud, and dust, adhering to the camera  36  or another signal indicating that an image can be normally acquired may be input instead into the integrative control unit  111 . 
     Information, for example, detected by the sensors  32 ,  34 , and  35  and the camera  36  and information output from the wiper operation receiving unit  37  are input into the integrative control unit  111  via the vehicle control unit  3 . As for “input via the vehicle control unit  3 ,” information may be input into the integrative control unit  111  without being processed by the vehicle control unit  3 , or information that is different from information from the sensors  32 ,  34 , and  35  and the camera  36  or information from the wiper operation receiving unit  37  may be input into the integrative control unit  111  after the vehicle control unit  3  perform some processing based on information acquired by the vehicle control unit  3  from the sensors  32 ,  34 , and  35  and the camera  36  or information from the wiper operation receiving unit  37 . The integrative control unit  111  generates an operation signal for operating the first air curtain device  130  based on the input information to transmit the generated operation signal to the air curtain control unit  138 . The air curtain control unit  138  controls operation of the motor  133  based on the operation signal input from the integrative control unit  111 . 
     Next, operation of the air curtain device will be described. Operation of the first air curtain device  130  will be described in the following, and operation of the second to fourth air curtain devices  150 ,  170 , and  190  is similar. 
       FIG. 18  is a timing chart showing a relationship between: a wiper operation signal that is received by the wiper operation receiving unit  37  and indicates that the wiper is operating; and an air curtain operation signal for operating the first air curtain device  130 . 
     The wiper operation signal is, for example, high (on) when the driver turns on the wiper operator and is low (off) when the driver turns off the wiper operator. For example, if the vehicle control unit  3  automatically operates the wiper based on a predetermined condition, the wiper operation signal may be high or low depending on whether the predetermined condition is satisfied. The air curtain operation signal is high (on) when the first air curtain device  130  is operated and is low (off) when the first air curtain device  130  is stopped. 
     As shown in  FIG. 18 , for example, when the wiper operator is turned on by the driver, a wiper on signal  1201  indicating that the wiper operator is turned on is output from the wiper operator. The wiper on signal  1201  is input into the integrative control unit  111  via the vehicle control unit  3 . The integrative control unit  111  determines whether the wiper is operating based on the input wiper on signal  1201 . The wiper is operated since it is raining around the vehicle  1 . Accordingly, the integrative control unit  111  outputs an air curtain on signal  1202  to operate the first air curtain device  130  when the integrative control unit  111  acquires the wiper on signal  1201 . The output air curtain on signal  1202  is input into the air curtain control unit  138  of the first air curtain device  130 . The air curtain control unit  138  operates the motor  133  to continuously blow air from the air blowing mechanism  137  toward the cleaning surface  21  of the front LiDAR  6   f  at a predetermined wind speed. 
     On the other hand, when the wiper operator is turned off by the driver, a wiper off signal  1203  indicating that the wiper operator is turned off is output from the wiper operator. The wiper off signal  1203  is input to the integrative control unit  111  via the vehicle control unit  3 . The integrative control unit  111  determines whether the wiper is operating based on the input wiper off signal  1203 . The wiper is turned off since it is not raining around the vehicle  1 . Accordingly, the integrative control unit  111  outputs an air curtain off signal  1204  to stop the first air curtain device  130  when the integrative control unit  111  acquires the wiper off signal  1203 . The output air curtain off signal  1204  is input into the air curtain control unit  138 . The air curtain control unit  138  stops the motor  133  to stop the air blown toward the cleaning surface  21  of the front LiDAR  6   f.    
     The air curtain system  100 C according to the present embodiment includes: the first air curtain device  130  configured to prevent dirt from adhering to the front LiDAR  6   f ; the information acquisition unit  30  configured to acquire information indicating bad weather; and the integrative control unit  111  configured to control the first air curtain device  130 . The integrative control unit  111  is configured to operate the first air curtain device  130  when it is determined that the wiper is operating based on the wiper operation signal acquired by the wiper operation receiving unit  37  (the information acquisition unit  30 ). According to this configuration, since the first air curtain device  130  can be operated only when it is determined that the weather is bad, or it is raining, the power consumption of the air curtain system  100 C can be reduced. 
     Although the first air curtain device  130  is operated in accordance with operation of the wiper in the operation example described above, the present invention is not limited thereto. For example, the first air curtain device  130  may be operated based on the operation of the wiper and a temperature around the vehicle as below. 
       FIG. 19  is a timing chart showing a relationship among a wiper operation signal, temperature information indicating a temperature around the vehicle, and an air curtain operation signal. 
     The temperature information is an on/off signal output based on a temperature T around the vehicle  1  acquired by the thermometer  35 . The temperature T around the vehicle  1  acquired by the thermometer  35  is input into the integrative control unit  111  via the vehicle control unit  3 . The integrative control unit  111  outputs temperature information in accordance with whether the input temperature T is equal to or lower than a predetermined temperature T 0  (for example, 0° C.). As the temperature information, the integrative control unit  111  outputs an on (high) signal when the temperature T around the vehicle  1  is lower than the predetermined temperature T 0  and outputs an off (low) signal when the temperature T around the vehicle  1  is equal to or higher than the predetermined temperature T 0 . That is, the first air curtain device  130  is operated when the wiper is operating and an outside temperature is lower than or equal to the freezing point, or when it is inferred that it is snowing. 
     As shown in  FIG. 19 , the integrative control unit  111  is configured to operate the first air curtain device  130  only when the wiper on signal and the on temperature information are acquired. 
     When the integrative control unit  111  acquires the wiper on signal  1205  and the off temperature information (a signal  1206 ), it is inferred that it is raining but not snowing. Therefore, the integrative control unit  111  maintains the output of an air curtain off signal  1207  and does not operate the first air curtain device  130 . 
     When the integrative control unit  111  acquires a wiper on signal  1208  and the on temperature information (a signal  1209 ), it is inferred that it is snowing. Therefore, the integrative control unit  111  outputs an air curtain on signal  1210  to operate the first air curtain device  130 . The output air curtain on signal  1210  is input into the air curtain control unit  138 . The air curtain control unit  138  operates the motor  133  to continuously blow air from the air blowing mechanism  137  toward the cleaning surface  21  of the front LiDAR  6   f  at a predetermined wind speed. 
     When the integrative control unit  111  acquires a wiper off signal  1211  and the on temperature information (signal  1209 ), it is inferred that an outside temperature is low but it is not snowing. Therefore, the integrative control unit  111  outputs an off signal  1212  to the first air curtain device  130  and does not operate the first air curtain device  130 . 
     According to the air curtain system  100 C, the integrative control unit  111  operates the first air curtain device  130  when it is determined, based on the wiper operation signal acquired by the wiper operation receiving unit  37  and the temperature around the vehicle acquired by the thermometer  35 , that the temperature T outside the vehicle is equal to or lower than the predetermined temperature TO ( 0 ° C.) and the wiper is operating. According to this configuration, since the first air curtain device  130  can be operated only when it is determined that the weather is bad, or it is snowing, the power consumption of the air curtain system  100 C can be reduced. 
     When it is determined that the wiper is operating (the wiper on signal  1205 ) and an outside temperature is high  1206 , the on signal may be output to the first air curtain device  130  to continuously blow air at the predetermined wind speed V 1  since it is inferred that it is raining around the vehicle  1 , and when it is determined that the wiper is operating (the wiper on signal  1208 ) and an outside temperature is low  1209 , the first air curtain device  130  may continuously blow air at the predetermined wind speed V 2 , which is higher than V 1 , since it is inferred that it is snowing around the vehicle  1 , unlike in the operation example shown in  FIG. 19 . 
     The first air curtain device  130  may be operated, for example, based on an image captured by the camera  36  as below.  FIG. 20  is a timing chart showing a relationship between image determination and an air curtain operation signal. 
     The integrative control unit  111  is configured to analyze an image around the vehicle  1  acquired by the camera  36  to determine whether the weather is bad. When it is raining, the image captured by the camera  36  contains many streaks extending in the upper-lower direction. When it is snowing, the image captured by the camera  36  contains many streaks extending from the upper side to the lower side staggeringly in the left-right direction or many dots. For example, when the integrative control unit  111  detects more streaks extending in the upper-lower direction in the captured image than a predetermined number, the integrative control unit  111  determines that it is raining around the vehicle  1  to output a high signal (high output  1213 ). When the integrative control unit  111  detects more streaks extending from the upper side to the lower side staggeringly in the left-right direction or more dots in the captured image than a predetermined number, the integrative control unit  111  determines that it is snowing around the vehicle  1  to output a high signal (high output  1213 ). The integrative control unit  111  outputs a low signal (low output  1215 ) when it does not output a high signal. 
     As shown in  FIG. 20 , the integrative control unit operates the first air curtain device  130  when a high signal is output (High output  1213 ) based on the analysis of the image acquired by the camera  36  and does not operate the first air curtain device  130  when a low signal is output (Low output  1215 ). 
     According to the air curtain system  100 C, the integrative control unit  111  analyzes the image captured by the camera  36  to operate the first air curtain device  130  only when the integrative control unit  111  determines that it is raining or snowing. According to this configuration, since the first air curtain device  130  can be operated only when it is determined that the weather is bad, or it is raining or snowing, the power consumption of the air curtain system  100 C can be reduced. 
     The first air curtain device  130  may be operated, for example, based on weather information obtained by wireless communication as blow. 
       FIG. 21  is a timing chart showing a relationship between weather information and an air curtain operation signal. 
     The weather information is information about weather provided by an infrastructure facility around the vehicle  1 . The wireless communication unit  10  of the vehicle  1  acquires the weather information from the infrastructure facility. The weather information acquired by the wireless communication unit  10  is input into the integrative control unit  111  via the vehicle control unit  3  or is directly input into the integrative control unit  111 . 
     As shown in  FIG. 21 , when the integrative control unit  111  acquires weather information indicating that it is raining or snowing, the integrative control unit  111  outputs an on signal  1218  to the first air curtain device  130  to operate the first air curtain device  130 . When the integrative control unit  111  acquires weather information indicating that it is not raining or snowing, the integrative control unit  111  outputs an off signal  1220  to the first air curtain device  130  and does not operate the first air curtain device  130 . 
     According to the air curtain system  100 C, the integrative control unit  111  operates the first air curtain device  130  when the weather information is acquired indicating that it is raining or snowing based on the weather information acquired by the wireless communication unit  10 . According to this configuration, since the first air curtain device  130  can be operated only when it is determined that the weather is bad, or it is raining or snowing, the power consumption of the air curtain system  100 C can be reduced. 
     Although the operation signal for operating the first air curtain device  130  is generated by the integrative control unit  111  based on the weather information acquired by the information acquisition unit  30  in the fifth embodiment, the present invention is not limited thereto. The operation signal may be generated, for example, by the vehicle control unit  3 . In this case, the vehicle control unit  3  transmits the generated operation signal to the air curtain control unit  138  via the integrative control unit  111 . The air curtain control unit  138  controls the operation of the motor  133  based on the operation signal output from the vehicle control unit  3 . 
     Although the air curtain device is included in the air curtain system  100 C in the fifth embodiment, the present invention is not limited thereto. For example, the air curtain device and the cleaner device may be mounted on the vehicle  1  independently. Alternatively, only the air curtain device may be mounted on the vehicle  1 . In these cases, the air curtain control unit of the air curtain device is configured to directly acquire, from the vehicle control unit  3 , the weather information acquired by the information acquisition unit  30 . 
     Although the air curtain device has been described in which air is continuously and constantly ejected during operation in the fifth embodiment, the present invention is not limited thereto. For example, the first air curtain device may be configured to eject high-pressure air toward the cleaning object intermittently. Dirt may adhere to the cleaning object even if air is continuously or intermittently ejected from the air nozzle  163  or when the air curtain system  100 C is not operating. Therefore, for example, when it is determined that dirt adhered to the cleaning object or when an input from a driver for operating a cleaner device is received, the cleaning liquid may be ejected from the cleaner device toward the cleaning object and then the high-pressure air may be intermittently ejected from the air curtain device to remove the dirt adhering to the cleaning object. 
     Various Modifications 
     Embodiments of the present invention have been described above. It goes without saying that a technical scope of the present invention should not be limitedly interpreted by the description of the embodiments. It is to be understood by those skilled in the art that the embodiments are simply examples and various modifications may be made within the scope of the invention described in the claims. The technical scope of the present invention should be determined based on the scope of the invention described in the claims and equivalents thereof. 
     Although the driving modes of the vehicle according to the above embodiments include: the full automation mode; the advanced driver assistance mode; the driver assistance mode; and the manual driving mode, the driving modes of the vehicle should not be limited to these four modes. The driving modes of the vehicle may include at least one of these four modes. For example, only one driving mode of the vehicle may be executed. 
     Further, a classification and a name of the driving modes of the vehicle may be changed according to laws or regulations concerning self-driving in each country, as appropriate. Similarly, definitions of the “full automation mode,” the “advanced driver assistance mode,” and the “driver assistance mode” in the description of the embodiments are simply examples and may be changed according to laws or regulations concerning self-driving in each country, as appropriate. 
     Although the cleaner system  100  or the air curtain system  100 C is mounted on a vehicle configured to travel in self-driving mode in the above embodiments, the cleaner system  100  or the air curtain system  100 C may be mounted on a vehicle incapable of traveling in self-driving mode. 
     Although the cleaner system  100  includes the external sensor  6  in the above embodiments, the cleaner system  100  may not include the external sensor  6 . However, the cleaner system  100  provided as a unit including the external sensor  6  is preferable since positioning accuracy of the cleaners  103  to  106 ,  109   a , and  109   b  to the external sensor  6  can be improved. In addition, assemblability to the vehicle  1  is improved since the external sensor  6  can be attached to the vehicle  1  together with the cleaner system  100 . 
     Although a device configured to clean the LiDARs  6   f ,  6   b ,  6   r , and  6   l , a device configured to clean the front camera  6   c , and a device configured to clean the rear camera  6   d  have been described as a cleaner or an air curtain device configured to clean the external sensor  6  and prevent dirt from adhering to the external sensor  6  in the above embodiments, the present invention is not limited thereto. The cleaner system  100  may include a cleaner, an air curtain device, or the like configured to clean a radar and the like, instead of or together with the sensor cleaners  103  to  106 ,  109   a , and  109   b  or may include the cleaner, the air curtain device. 
     The external sensor  6 , such as the LiDARs  6   f ,  6   b ,  6   r , and  6   l , may have a detection surface and a cover covering the detection surface. A cleaner or an air curtain device configured to clean the external sensor  6  and prevent dirt from adhering to the external sensor  6  may be configured to clean (blow air to) the detection surface or to clean (blow air to) the cover covering the sensor. 
     The cleaning liquid ejected from the cleaner system  100  contains water or detergent. Cleaning media ejected toward the front window  1 f, the rear window  1   b , the headlamps  7   r  and  7   l , the LiDARs  6   f ,  6   b ,  6   r , and  6   l , and the cameras  6   c  and  6   d  may be different or the same. 
     The cleaners  101  to  109   b  are provided with one or more ejection ports for ejecting cleaning medium. The cleaners  101  to  109   b  may be provided with one or more ejection ports for ejecting the cleaning liquid and one or more ejection ports for ejecting air. 
     The cleaners  101  to  109   b  may be individually provided, or some of the cleaners may be unitized. For example, the right LC  105  and the right HC  107  may be a single unit. If the right headlamp  7   r  and the right LiDAR  6   r  are integrated, the right LC  105  and the right HC  107  may be a single unit. 
     The present application is based on Japanese Patent Application Nos. 2019-113841, 2019-113842, 2019-113843, and 2019-113844, filed on Jun. 19, 2019, the contents of which are incorporated herein by reference.