JP6662362B2 - Dust concentration detector - Google Patents

Description

  The present invention relates to a dust concentration detection device including a dust sensor that detects the concentration of dust contained in air.

  BACKGROUND ART Conventionally, there is a ventilation device described in Patent Document 1. This ventilator is equipped with a dust sensor having a light-emitting part and a light-receiving part, and detects floating particles in the air by receiving light reflected from the light-emitting part and reflected by the floating particles at the light-receiving part. I am trying to do it.

  The ventilator includes a sensor storage unit provided facing an air passage inside a housing of the ventilation device, and a shutter disposed at a boundary between the air passage inside the housing of the ventilation device and the sensor storage unit. In addition, when dew condensation occurs on the light emitting unit and the light receiving unit of the dust sensor, the shutter is closed so as not to detect floating particles in order to prevent erroneous determination and failure of the dust sensor.

JP 2015-25587 A

  The ventilation device described in Patent Literature 1 has a problem that, after dew condensation has occurred on the dust sensor, when the dew condensation on the dust sensor has been resolved, it cannot be accurately determined that the dew condensation on the dust sensor has been resolved. .

  SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to accurately determine that dew condensation on a dust sensor has been eliminated when dew condensation on the dust sensor has been eliminated.

  To achieve the above object, the invention according to claim 1 has a light emitting unit (321) for irradiating light and a light receiving unit (322) for receiving light, and the light emitted from the light emitting unit is air. Sensor (32) for detecting the concentration of dust contained in air by receiving light reflected by the dust contained in the dust and a condensation determining unit for determining whether or not condensation has occurred on the dust sensor (S80) When the dew condensation determining unit determines that dew condensation has occurred on the dust sensor, the dew condensation amount estimating the dew condensation amount generated on the dust sensor using at least one of the temperature and humidity of the air around the dust sensor. An estimating unit (S110); and a dew condensation elimination time specifying unit (S130) for specifying a dew condensation elimination time until dew condensation generated on the dust sensor is eliminated based on the dew amount estimated by the dew amount estimating unit. ing.

  According to such a configuration, when it is determined that dew condensation has occurred on the dust sensor, the amount of dew condensation generated on the dust sensor is estimated using at least one of the temperature and humidity of the air around the dust sensor, and the estimation is made. Since the condensation elimination time until the condensation generated on the dust sensor is eliminated is specified based on the amount of condensation, when the condensation of the dust sensor is eliminated, it is necessary to accurately determine that the condensation of the dust sensor has been eliminated. Can be.

  In addition, reference numerals in parentheses of each means described in this column and in the claims indicate a correspondence relationship with specific means described in the embodiment described later.

FIG. 2 is a block diagram schematically illustrating a schematic configuration of an air conditioning unit and an air conditioning control device in the first embodiment. FIG. 2 is an explanatory diagram for simply explaining a principle of detecting a dust concentration by the dust sensor in FIG. 1. It is sectional drawing which showed typically the schematic structure of the dust sensor of FIG. FIG. 2 is a block diagram simply showing an electrical configuration until the dust sensor of FIG. 1 detects dust concentration and outputs a signal indicating the dust concentration. 3 is a flowchart illustrating a control process executed by the air-conditioning control device in the first embodiment. 3 is a flowchart illustrating a control process executed by the air-conditioning control device in the first embodiment. FIG. 6 is a diagram exemplifying a waveform of a dust concentration detection value with elapsed time as a horizontal axis in order to explain the control processing of FIG. 5 in the first embodiment. FIG. 6 is a diagram exemplifying a waveform of a dust density detection value when the dust density detection value suddenly changes to a side where the time change ratio of the dust density detection value increases in order to explain the control processing of FIG. 5 in the first embodiment. It is a figure showing the relation between dew condensation elimination time and the amount of dew condensation. FIG. 9 is a block diagram schematically illustrating a schematic configuration of an air conditioning unit and an air conditioning control device in a second embodiment. It is a flow chart which showed control processing which an air-conditioning control device performs in a 2nd embodiment. FIG. 13 is a block diagram schematically illustrating a schematic configuration of an air conditioning unit and an air conditioning control device in a third embodiment. It is a flow chart which showed control processing which an air-conditioning control device performs in a 3rd embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, parts that are the same or equivalent are denoted by the same reference numerals in the drawings.

(1st Embodiment)
A dust concentration detection device according to the present embodiment will be described with reference to FIGS. As shown in FIG. 1, the dust concentration detection device has a dust sensor 32 disposed in an air conditioning case 21 of an air conditioning unit 2 in a vehicle air conditioner 1 mounted on a vehicle. The density of the dust contained in the air flowing through the ventilation path 24 formed by the above is detected.

  The vehicle air conditioner 1 includes an air conditioner unit 2 and an air conditioner controller 40. The air-conditioning unit 2 is a vehicle air-conditioning unit that is installed in a vehicle compartment and air-conditions the vehicle compartment. For example, the air-conditioning unit 2 is installed in an instrument panel arranged on the vehicle front side in the vehicle interior. In addition, each arrow DR1, DR2 of FIG. 1 shows the direction of the vehicle in which the air conditioning unit 2 is mounted. That is, the arrow DR1 in FIG. 1 indicates the vehicle longitudinal direction DR1, and the arrow DR2 indicates the vehicle vertical direction DR2. These directions DR1 and DR2 are directions crossing each other, or strictly speaking, directions orthogonal to each other.

  As shown in FIG. 1, the air conditioning unit 2 includes an air conditioning case 21, an inside / outside air switching door 22, a blower 23, an evaporator 26, a heater core 27, an air mix door 28, an air filter 30, an outlet opening door 254, 255, 256, and the like. have.

  The air-conditioning case 21 has a certain degree of elasticity and is formed of a resin excellent in strength. As a resin forming the air-conditioning case 21, for example, polypropylene is used. The air-conditioning case 21 forms an outer shell of the air-conditioning unit 2, and inside the air-conditioning case 21, an air passage through which air blown into the vehicle compartment flows, that is, a ventilation passage 24 is formed. The air-conditioning case 21 also has an inside air inlet 241 for introducing inside air into the ventilation passage 24 from a predetermined location in the vehicle compartment, and an outside air from outside the vehicle to the ventilation passage 24 on the upstream side in the air flow direction of the ventilation passage 24. And an outside air inlet 242. Here, the inside air is air inside the vehicle cabin, and the outside air is air outside the vehicle cabin.

  In addition, the air conditioning case 21 has a plurality of blowout openings 251, 252, and 253 for blowing air from the ventilation path 24 to the front seat area in the vehicle compartment on the downstream side of the ventilation path 24 in the air flow direction. . The plurality of outlets 251, 252, 253 include a face outlet 251, a foot outlet 252, and a defroster outlet 253.

  The face blowing opening 251 blows out conditioned air toward the upper body of the occupant seated on the front seat. The foot outlet 252 blows out conditioned air toward the feet of the occupant. The defroster blowing opening 253 blows out conditioned air toward the front window of the vehicle.

  Inside the air conditioning case 21, an inside / outside air switching door 22, a blower 23, an evaporator 26, a heater core 27, an air mixing door 28, and the like are provided.

  The inside / outside air switching door 22 continuously adjusts the opening area of the inside air introduction port 241 and the opening area of the outside air introduction port 242. The inside / outside air switching door 22 is driven by an actuator such as a servo motor (not shown). The inside / outside air switching door 22 rotates so as to open one of the inside air inlet 241 and the outside air inlet 242 and close the other. This allows the inside / outside air switching door 22 to adjust the ratio of the amount of inside air introduced into the ventilation path 24 to the amount of outside air.

  As the air intake mode to the ventilation passage, there are an inside air mode for introducing inside air inside the vehicle and an outside air mode for introducing outside air outside the vehicle. For example, in the inside air mode in which only the inside air is introduced into the ventilation passage 24, the inside / outside air switching door 22 is positioned at an operating position in which the inside air introduction port 241 is opened while the outside air introduction port 242 is closed. Conversely, in the outside air mode in which outside air is exclusively introduced into the ventilation path 24, the inside / outside air switching door 22 is positioned at an operating position in which the inside air introduction port 241 is closed while the outside air introduction port 242 is opened.

  The blower 23 is a centrifugal blower that blows air, and includes a centrifugal fan 231 arranged in the ventilation path 24 and a motor (not shown) that drives the centrifugal fan 231 to rotate. When the centrifugal fan 231 of the blower 23 is driven to rotate, an airflow is formed in the ventilation path 24. Thus, the air introduced into the ventilation path 24 from the inside air introduction port 241 or the outside air introduction port 242 flows through the ventilation path 24, and at least the face blowout opening 251, the foot blowout opening 252, and the defroster blowout opening 253. It is blown out from one. The air flows roughly in the direction of the air flow downstream of the centrifugal fan 231 in the ventilation passage 24 in the direction indicated by the arrow Ar.

  The face blowout opening door 254 is provided in the face blowout opening 251, and adjusts the opening area of the face blowout opening 251. The foot outlet door 255 is provided in the foot outlet 252 and adjusts the opening area of the foot outlet 252. The defroster outlet opening 256 is provided in the defroster outlet 253, and adjusts the opening area of the defroster outlet 253.

  The evaporator 26 is a heat exchanger for cooling the air flowing through the ventilation passage 24. The evaporator 26 exchanges heat between the air passing through the evaporator 26 and the refrigerant, thereby cooling the air and evaporating the refrigerant.

  The heater core 27 is a heat exchanger for heating air flowing through the ventilation passage 24. The heater core 27 exchanges heat between, for example, engine cooling water and air passing through the heater core 27, and heats the air with the heat of the engine cooling water. The heater core 27 is disposed downstream of the evaporator 26 in the air flow direction.

  An air mix door 28 is provided between the evaporator 26 and the heater core 27 of the air conditioning unit 2. The air mix door 28 adjusts the ratio of the amount of air that passes through the evaporator 26 and bypasses the heater core 27 and the amount of air that passes through the heater core 27 after passing through the evaporator 26.

  The air filter 30 is disposed between the blower 23 and the evaporator 26 in the ventilation path 24 of the air conditioning case 21. In other words, the air filter 30 is arranged downstream of the blower 23 in the air flow direction and upstream of the evaporator 26 in the air flow direction.

  The air filter 30 captures a certain amount of dust and the like contained in the air passing through the air filter 30. Therefore, the air blown out from the blower 23 flows into the evaporator 26 after dust and the like in the air are removed to some extent by the air filter 30.

  Since the air filter 30 is provided in the ventilation path 24 of the air-conditioning case 21, the air-conditioning control device 40 can operate the air-conditioning unit 2 to reduce the dust concentration in the passenger compartment. In such an operation, the air conditioning control device 40 operates the blower 23, for example, after setting the air conditioning unit 2 to the inside air mode. Then, as the amount of air blown by the blower 23 increases, the dust removal ability of the air conditioning unit 2 for removing dust in the vehicle interior increases.

Next, the dust sensor 32 will be described. The dust sensor 32 is disposed in the air-conditioning case 21 in which the ventilation path 24 through which the air blown into the vehicle flows is formed, and detects the concentration of dust contained in the air flowing through the ventilation path 24. As shown in FIGS. 2 and 3, the dust sensor 32 detects a dust concentration which is a concentration of suspended particles contained in air at a predetermined sensing area Are, and outputs a detection signal indicating the detected dust concentration to the air conditioning control device 40. Output to The dust concentration is also referred to as a dust concentration, more specifically, a mass concentration of dust contained in the air, and a unit of the dust concentration is, for example, “μg / m ³ ”.

  The dust sensor 32 of the present embodiment is an optical dust sensor configured to detect a dust concentration by a light scattering method. That is, the dust sensor 32 includes a light emitting unit 321 that emits light, a light receiving unit 322 that receives the light emitted by the light emitting unit 321, and a sensor case 323 that houses the light emitting unit 321 and the light receiving unit 322. The dust sensor 32 detects the concentration of dust contained in the air flowing through the ventilation passage 24 by the light receiving unit 322 receiving the reflected light reflected by the light emitted from the light emitting unit 321.

  Therefore, a part of the air flowing through the ventilation path 24 of the air conditioning case 21 is introduced into the sensor case 323 of the dust sensor 32. Specifically, the dust sensor 32 is disposed downstream of the blower 23 in the air flow direction with respect to the centrifugal fan 231 and upstream of the air filter 30 in the air flow direction. Therefore, air is introduced into the sensor case 323 from between the centrifugal fan 231 and the air filter 30 in the ventilation path 24. That is, in the present embodiment, a portion between the centrifugal fan 231 and the air filter 30 in the ventilation path 24 is a sensing location of the dust sensor 32.

  The light emitting section 321 of the dust sensor 32 has a light emitting element 321a composed of a light emitting diode, for example, and an irradiation light lens 321b. The light receiving section 322 has a light receiving element 322a composed of a photodiode, for example, and a condenser lens 322b. Light emitted from the light emitting element 321a and passing through the irradiation light lens 321b as shown by an arrow B1 in FIG. 3 is reflected on dust in the air introduced into the sensor case 323, and the reflected light is shown by an arrow B2. Is received by the light receiving element 322a through the condenser lens 322b. A current corresponding to the amount of received light flows through the light receiving element 322a.

  As shown in FIG. 4, the dust sensor 32 has a sensor circuit 324. The sensor circuit 324 amplifies the current of the light receiving element 322a, converts the amplified current into a voltage, amplifies the voltage, and outputs a voltage. I do. The voltage output of the dust sensor 32 is converted to a dust concentration. The dust sensor 32 detects the dust concentration in the ventilation path 24 in this way. Note that the vertical axis of the graph GF in FIG. 4 represents the dust concentration converted from the voltage value, that is, the concentration conversion value, and the horizontal axis of the graph GF represents the elapsed time.

  When high-temperature, high-humidity air is introduced around the dust sensor 32 in a state where the optical components such as the light emitting unit 321, the irradiation light lens 321b, the condenser lens 322b, and the light receiving element 322a of the dust sensor 32 are cooled. In addition, dew condensation occurs on each optical component of the dust sensor 32. As described above, when dew condensation occurs on each optical component of the dust sensor 32, the fluctuation of the voltage output of the dust sensor 32 increases.

  Further, as shown in FIG. 3, the dust sensor 32 of the present embodiment includes a thermistor 325 for detecting the temperature inside the sensor case 323. The thermistor 325 detects the temperature of the dust sensor 32 and outputs the detected temperature to the dust sensor control unit 50 as a temperature signal of the dust sensor 32.

  Next, the air conditioning control device 40 will be described. The air conditioning control device 40 illustrated in FIG. 1 is a control device that controls the air conditioning unit 2. Specifically, the air-conditioning control device 40 is an electronic control device including a processor and a storage unit configured by a non-transitional substantial storage medium such as a semiconductor memory. The air conditioning control device 40 executes a computer program stored in the storage unit. When the computer program is executed, a method corresponding to the computer program is executed. That is, the air-conditioning control device 40 executes various control processes, such as the processes in FIGS.

  The air conditioning control device 40 controls the operation of each actuator by outputting a control signal to each actuator included in the air conditioning unit 2. In short, the air conditioning control device 40 performs various air conditioning controls in the air conditioning unit 2. For example, the air blower 23, the inside / outside air switching door 22, the air mix door 28, the face blowout opening door 254, the foot blowout opening door 255, and the defroster blowout opening door 256 are driven and controlled by the air conditioning control device 40. .

  As shown in FIG. 1, for example, an operation device 44, a display device 46, and a communication unit 47 are electrically connected to the air-conditioning control device 40 in addition to sensors such as a dust sensor 32 and actuators such as doors. ing.

  The operating device 44 is an operating unit that is operated by an occupant when adjusting the amount, temperature, and the like of the conditioned air blown from the air conditioning unit 2. The operating device 44 is arranged, for example, on an instrument panel of a vehicle. The operating device 44 can set, for example, the amount of conditioned air, the target room temperature in the vehicle compartment, the outlet of the conditioned air, and the like. The operation device 44 can also set an automatic air-conditioning mode in which air volume adjustment of conditioned air, temperature adjustment of conditioned air, and selection of internal air circulation or introduction of external air are automatically performed. The operation device 44 outputs information indicating these settings, that is, operation information indicating an occupant operation performed on the operation device 44, to the air conditioning control device 40.

  For example, when the automatic air-conditioning mode is set by the operation device 44, the air-conditioning control device 40 inputs the air volume of the air blower 23 and the operation of each door 22, 28, 254, 255, 256 from a plurality of sensors. Automatically adjust or control based on signal.

  The display device 46 is a display unit that displays various information of the air conditioning unit 2. That is, signals indicating various information of the air conditioning unit 2 are input to the display device 46 from the air conditioning control device 40, and the display device 46 performs display according to the input signals from the air conditioning control device 40.

  The display device 46 is disposed at a position that is easy for an occupant in the vehicle compartment to see, such as an instrument panel of the vehicle. The display device 46 may be included in a display device of another vehicle-mounted device such as a car navigation device, or may be configured as a dedicated device for the air conditioning unit 2.

  The communication unit 47 communicates with external devices such as various ECUs. The air conditioning control device 40 including the dust sensor control unit 50 notifies information such as the detected value of the dust concentration detected by the dust sensor 32 to external devices such as various ECUs via the communication unit 47.

  A signal indicating the outside air temperature, the outside air humidity, the inside air temperature, the inside air humidity, and a door open / close signal are input to the air conditioning control device 40. The outside air temperature is detected by an outside air temperature sensor that detects the temperature outside the vehicle, and the outside air humidity is detected by an outside air humidity sensor that detects the relative humidity outside the vehicle. The inside air temperature is detected by an inside air temperature sensor that detects the temperature inside the vehicle, and the inside air humidity is detected by an inside air humidity sensor that detects the relative humidity inside the vehicle. The door open / close signal is a signal indicating that the door of the vehicle has opened and closed the door opening of the vehicle, and is input from a door open switch (not shown).

  Next, processing executed by the air conditioning control device 40 and the dust sensor control unit 50 will be described with reference to FIGS. FIGS. 5 to 6 are flowcharts showing processing executed by the air conditioning control device 40 and the dust sensor control unit 50. Here, the control process will be described with the air-conditioning control device 40 and the dust sensor control unit 50 as control units. The control unit periodically executes the flowcharts of FIGS. 5 and 6 while the air conditioning unit 2 is operating, for example.

  First, in step S10, the control unit acquires the outside air temperature detected by the outside air temperature sensor, and in step S20, the control unit acquires the outside air humidity detected by the outside air humidity sensor.

  Next, in step S30, the control unit acquires the inside air temperature detected by the inside air temperature sensor, and in step S40, the control unit acquires the inside air humidity detected by the inside air humidity sensor.

  Next, in step S50, the control unit obtains a dust concentration detection value Dm detected by the dust sensor 32, that is, a dust concentration detection value Dm, based on the detection signal from the dust sensor 32. In short, the control unit detects the dust concentration according to the detection signal from the dust sensor 32.

  Next, in step S60, the control unit determines whether or not the condensation flag is set. Specifically, it is determined whether or not a condensation flag indicating that condensation has occurred on the dust sensor 32 is set in the storage unit. The dew condensation flag is set by the control unit itself.

  Here, it is assumed that no condensation has occurred on the dust sensor 32 and the condensation flag has not been set in the storage unit. If the dew condensation flag is not set in the storage unit, the control unit determines in step S70 whether a door open / close signal has been input from a door open switch (not shown).

  When the vehicle door opens and closes the door opening while the air in the cabin is cooled by the cooling, when the outside air of high temperature and high humidity outside the cabin enters the cabin through the vehicle door opening, There is a possibility that outside air of high temperature and high humidity outside the room is sucked into the ventilation path 24 and dew condensation occurs on the dust sensor 32. In order to grasp such a situation, in step S70, the control unit determines whether or not the vehicle door has been opened / closed based on whether or not a door open / close signal has been input from the door open switch.

  Here, when a door open / close signal is input from the door open switch, the control unit determines whether or not dew condensation has occurred on the dust sensor 32 in step S80. For example, as shown in FIGS. 7 and 8, when the time change rate of the dust concentration detection value Dm, that is, the gradient of the dust concentration detection value Dm suddenly changes beyond a predetermined limit, it is assumed that dew condensation occurs on the dust sensor 32. Is determined. This is because, when dew condensation occurs on the dust sensor 32, the light emitted from the light emitting unit 321 is reflected also in the dew water in the sensor case 323. That is, in this step S80, it is determined whether or not the dust concentration detection value Dm is affected by the condensation of the dust sensor 32. If the dust concentration detection value Dm is affected by the condensation, the dust sensor 32 It is determined that dew condensation has occurred.

  Here, when it is determined that the dew condensation has occurred on the dust sensor 32, the control unit specifies the outside air absolute humidity outside the vehicle compartment in step S90. The outside air absolute humidity outside the vehicle compartment can be specified using the outside air temperature acquired in step S10 and the outside air humidity acquired in S20.

Next, in step S100, the control unit specifies the amount of saturated steam in the vehicle compartment. Specifically, the control unit specifies the saturated steam amount corresponding to the inside air temperature acquired in step S30 as the saturated steam amount in the vehicle compartment. The unit of the amount of the saturated water vapor is represented, for example, as g / m ³ .

Next, in step S110, the control unit estimates the dew condensation amount of the dust sensor 32 based on the outside air absolute humidity outside the vehicle compartment specified in step 90 and the saturated water vapor amount in the vehicle compartment specified in step S100. The amount of dew condensation of the dust sensor 32 can be calculated as the volume outside air absolute humidity outside the vehicle compartment minus the saturated water vapor amount in the vehicle compartment. The volume outside air absolute humidity outside the vehicle compartment is the absolute humidity per unit volume, and the unit is expressed as g / m ³ .

  Next, in step S120, the control unit specifies the amount of air around the dust sensor 32. In the present embodiment, whether the air volume of the air around the dust sensor 32 is large or small is determined based on whether the voltage value for rotating the centrifugal fan 231 of the blower 23 is equal to or higher than a predetermined voltage. Identify.

  Next, in step S130, the control unit specifies the dew condensation elimination time of dust sensor 32. FIG. 9 shows the relationship between the dew condensation elimination time and the amount of dew condensation. As shown in the figure, the larger the amount of dew condensation, the longer the dew condensation elimination time. Further, when the wind speed of the air around the dust sensor 32 is the predetermined speed v, the dew condensation elimination time is shorter than when the wind speed of the air around the dust sensor 32 is 0. That is, when the air volume around the dust sensor 32 is large, the dew condensation elimination time is shorter than when the air speed around the dust sensor 32 is low.

  The relationship between the dew condensation elimination time and the amount of dew condensation shown in FIG. 9 is stored in the storage unit of the control unit as a map, and the control unit refers to this map and refers to the dew condensation of the dust sensor 32 identified in step S110. The dew condensation elimination time of the dust sensor 32 is specified based on the amount and the amount of air around the dust sensor 32 specified in step S120.

  Next, in step S140, the control unit outputs a dew condensation diagnostic indicating that dew condensation has occurred on the dust sensor 32 to the body ECU as an external device via the communication unit 47, and proceeds to A1 in FIG.

  When the body ECU receives the dew condensation diagnosis from the control unit via the communication unit 47, the body ECU causes the display device 46 to display that the dew condensation has occurred on the dust sensor 32.

  Next, in step S150, the control unit determines whether or not the condensation elimination time has elapsed. When the control unit determines in step S80 that dew condensation has occurred on the dust sensor 32, the control unit starts counting time by a timer, and determines whether the dew condensation elimination time has elapsed based on the count value of the timer. I do.

  If the condensation elimination time has not elapsed, the control unit sets or holds the condensation flag in step S180. That is, when the condensation flag is not set in the storage unit, the condensation flag is set in the storage unit, and when the condensation flag is already set in the storage unit, the setting of the condensation flag in the storage unit is held. .

  Next, in step S190, the control unit corrects the output value of the dust density acquired in step S50. The control unit of the present embodiment is configured to periodically store the output value of the dust sensor 32 when no dew condensation occurs on the dust sensor 32 in the storage unit. Since the output value of the dust sensor 32 when the dew condensation occurs on the dust sensor 32 has low accuracy, the output value of the most recent dust sensor 32 when the dew condensation does not occur on the dust sensor 32 is stored in the storage unit. And the output value of the dust sensor 32 read from the storage unit is corrected as the output value of the dust sensor 32.

  Next, in step S200, the control unit outputs the dust concentration from communication unit 47. Here, the output value of dust sensor 32 corrected in step S190 is output from communication unit 47, and the process ends.

  When it is determined in step S80 that dew condensation has occurred on the dust sensor 32, the dew condensation elimination time has elapsed. When it is determined in step S150 that the dew condensation elimination time has elapsed, the control unit proceeds to step S160. , Release the condensation flag. Specifically, the control unit deletes the dew flag stored in the storage unit.

  Next, in step S170, the control unit releases the dew condensation diagnostic indicating that dew condensation has occurred on the dust sensor 32. This process is performed by the dust sensor control unit 50 on the air conditioning control device 40. Specifically, the dust sensor control unit 50 stops outputting the dew condensation diag to the external device via the communication unit 47.

  If it is determined in step S60 that the condensation flag is set, the control unit proceeds to step S140 without performing steps S70 to S130. Therefore, the control unit continuously outputs the dew condensation diagnosis.

  If no door open / close signal is input from the door open switch in step S70, the control unit proceeds to step S200. Therefore, in S200, the control unit outputs the output value of the dust concentration acquired in Step S50 from communication unit 47.

  Here, although not shown, the control unit performs a process of switching the intake mode to the inside air mode when the intake mode is the outside air mode and the output value of the dust concentration is equal to or more than a predetermined value. Then, the voltage value for rotationally driving the centrifugal fan 231 of the blower 23 is increased so that the flow rate of the air passing through the air filter 30 is increased.

  If it is determined in step S80 that condensation has not occurred on the dust sensor 32, the control unit proceeds to step S200. In this case as well, the control unit outputs the output value of the dust concentration acquired in step S50 from the communication unit 47 in S200.

  As described above, the dust concentration detection device includes the light emitting unit 321 for irradiating light and the light receiving unit 322 for receiving light, and reflects the light emitted from the light emitting unit 321 to dust contained in air. A dust sensor 32 is provided for detecting the concentration of dust contained in the air by the light receiving unit 322 receiving the reflected light. Further, a dew condensation determining unit that determines whether or not dew condensation has occurred on the dust sensor 32, and when the dew condensation determining unit determines that dew condensation has occurred on the dust sensor, at least the temperature and humidity of the air around the dust sensor A dew amount estimating unit for estimating the dew amount generated on the dust sensor by using one of them. Further, a dew condensation elimination time specifying unit that specifies a dew condensation elimination time until the dew condensation generated on the dust sensor is eliminated based on the dew amount estimated by the dew condensation amount estimation unit is provided.

  According to such a configuration, when it is determined that dew condensation has occurred on the dust sensor 32, the amount of dew condensation generated on the dust sensor is estimated using at least one of the temperature and humidity of the air around the dust sensor 32, Since the dew condensation elimination time until the dew condensation generated on the dust sensor 32 is eliminated is specified based on the amount of dew condensation, when the dew condensation on the dust sensor 32 is eliminated, it is accurately determined that the dew condensation on the dust sensor 32 has been eliminated. Can be determined.

  It should be noted that it is also possible to determine whether or not the dew condensation on the dust sensor 32 has been eliminated based on whether or not the level of the output voltage of the dust sensor 32 has stabilized. However, since the output voltage level of the dust sensor 32 gradually becomes stable during the process of dew condensation occurring on the dust sensor 32, whether the dew condensation on the dust sensor 32 has been eliminated based on the output voltage level of the dust sensor 32 In such a configuration, it is difficult to accurately determine whether or not the dew condensation on the dust sensor 32 has been eliminated. For example, even though the dew condensation on the dust sensor 32 has not been completely eliminated, it may be erroneously determined that the dew condensation on the dust sensor 32 has been eliminated.

  However, as in the present embodiment, the amount of dew condensation generated on the dust sensor is estimated, and the dew condensation elimination time until the dew condensation generated on the dust sensor 32 is eliminated based on the amount of dew condensation is specified. When the condensation on the dust 32 has been eliminated, it can be accurately determined that the condensation on the dust sensor 32 has been eliminated.

  The dust concentration detection device further includes a wind speed estimating unit that estimates a wind speed of the air around the dust sensor 32, and the dew condensation elimination time specifying unit determines the wind speed of the air around the dust sensor estimated by the wind speed estimating unit. The dew condensation elimination time is specified based on the dew amount estimated by the dew amount estimating unit.

  Therefore, it is possible to specify the dew condensation elimination time in consideration of the influence of the wind speed of the air around the dust sensor.

  The dust sensor 32 is disposed in the air-conditioning case 21 in which the ventilation passage 24 through which the air blown into the vehicle flows is formed, and detects the concentration of dust contained in the air flowing through the ventilation passage.

  Thus, the dust sensor 32 is disposed in the air-conditioning case 21 in which the ventilation passage 24 through which the air blown into the vehicle is formed, and the concentration of the dust contained in the air flowing through the ventilation passage 24 is determined by the dust sensor 32. Can be detected.

  The dust concentration detection device further includes a door opening / closing determination unit that determines whether the door of the vehicle has been opened / closed by the vehicle door. If it is determined that the dust sensor has been opened and closed, it is determined whether or not dew condensation has occurred on the dust sensor.

  Therefore, for example, in a state where the air in the vehicle interior is cooled by cooling, the door of the vehicle opens and closes the door opening, and high temperature and high humidity outside air of the vehicle enters the vehicle interior from the vehicle door opening, In a situation where dew condensation may occur on the dust sensor 32, it is possible to specify the dew condensation elimination time until the dew condensation generated on the dust sensor 32 is eliminated.

  Further, the dust concentration detection device includes an outside air absolute temperature specifying unit (S90) for specifying an absolute temperature outside the vehicle, and a saturated water vapor amount specifying unit (S100) for specifying a saturated water vapor amount in the vehicle room. ing. Then, the dew condensation amount estimating unit calculates the amount of dew condensation generated on the dust sensor based on the absolute temperature of the vehicle outdoor specified by the outside air absolute temperature specifying unit and the saturated water vapor amount in the vehicle room specified by the saturated water vapor amount specifying unit. Is estimated.

  As described above, the absolute temperature outside the vehicle and the amount of saturated water vapor inside the vehicle are specified, and the amount of dew condensation generated on the dust sensor is estimated based on the absolute temperature outside the vehicle and the amount of saturated water vapor inside the vehicle. Thus, the condensation elimination time can be specified with high accuracy.

(2nd Embodiment)
A dust concentration detection device according to a second embodiment will be described with reference to FIGS. The outside air temperature, the outside air humidity, the inside air temperature, the inside air humidity, and the door open / close signal are input to the air conditioning control device 40 according to the first embodiment. As shown, the inside air temperature and the inside air humidity are input.

  FIG. 11 and FIG. 6 are flowcharts illustrating processing executed by the air conditioning control device 40 and the dust sensor control unit 50 of the present embodiment. 6 are the same as those in the control processing of the first embodiment, the description thereof is omitted here, and the description will focus on the parts shown in FIG.

  As shown in FIG. 11, first, in step S12, the control unit acquires the temperature of the dust sensor 32 detected by the thermistor 325.

  Next, in step S30, the control unit acquires the inside air temperature detected by the inside air temperature sensor, and in step S40, the control unit acquires the inside air humidity detected by the inside air humidity sensor.

  Next, in step S50, the control unit obtains, based on the detection signal from the dust sensor 32, a detection value Dm of the dust concentration detected by the dust sensor 32, that is, a dust concentration detection value Dm. In step S60, the control unit It is determined whether the dew condensation flag is set.

  Here, it is assumed that no condensation has occurred on the dust sensor 32 and the condensation flag has not been set in the storage unit. When the dew condensation flag is not set in the storage unit, the control unit determines in step S62 whether the intake mode is the inside air mode. Specifically, the control unit determines whether the intake mode is the inside air mode or the outside air mode.

  Here, when the intake mode is set to the inside air mode, the control unit determines whether or not dew condensation has occurred on the dust sensor 32 in step S80.

  Here, when it is determined that dew condensation has occurred on the dust sensor 32, the control unit specifies the inside air absolute humidity in the vehicle compartment in step S92. The inside air absolute humidity in the vehicle compartment can be specified using the inside air temperature acquired in step S20 and the inside air humidity acquired in step S30.

  Next, in step S94, the control unit specifies the saturated water vapor amount of the dust sensor 32. Specifically, the control unit specifies the saturated water vapor amount corresponding to the temperature of the dust sensor 32 acquired in step S10 as the saturated water vapor amount of the dust sensor 32.

Next, in step S110, the control unit estimates the dew condensation amount of the dust sensor 32 based on the inside air absolute humidity in the vehicle cabin specified in step 92 and the saturated water vapor amount of the dust sensor 32 specified in step S94. . The amount of dew condensation of the dust sensor 32 can be calculated as the volume inside air absolute humidity in the vehicle compartment minus the amount of saturated water vapor of the dust sensor 32. The volume inside air absolute humidity outside the vehicle compartment is the absolute humidity per unit volume, and the unit is expressed as g / m ³ .

  Next, in step S120, the control unit specifies the amount of air around the dust sensor 32. Specifically, the control unit specifies whether the air volume around the dust sensor 32 is large or small.

  Next, in step S130, the control unit specifies the dew condensation elimination time of dust sensor 32. The relationship between the dew condensation elimination time and the amount of dew condensation shown in FIG. 9 is stored in the storage unit of the control unit as a map, and the control unit refers to this map and refers to the dew condensation of the dust sensor 32 identified in step S110. The dew condensation elimination time of the dust sensor 32 is specified based on the amount and the amount of air around the dust sensor 32 specified in step S120. The control unit specifies the dew condensation elimination time of the dust sensor 32 so as to correspond to the air volume around the dust sensor 32 specified in step S120, and proceeds to step S140.

  As described above, the dust concentration detection device includes the inside air mode determination unit that determines whether the intake mode to the ventilation passage 24 is the inside air mode for introducing the inside air of the vehicle interior. When the mode determination unit determines that the intake mode is the inside air mode, the condensation determination unit determines whether or not condensation has occurred on the dust sensor 32.

  Thus, when it is determined that the intake mode is the inside air mode, it is possible to determine whether or not dew condensation has occurred on the dust sensor 32.

  Further, the dust concentration detecting device includes a sensor temperature specifying unit that specifies the temperature of the dust sensor 32, an inside air temperature specifying unit that specifies the temperature in the vehicle interior, and an indoor humidity specifying unit that specifies the humidity in the vehicle interior. , Is provided. The dew condensation amount estimating unit is configured to determine, when the mode determining unit determines that the intake mode is the inside air mode, the indoor temperature of the vehicle identified by the indoor air temperature identifying unit and the interior of the vehicle identified by the indoor humidity identifying unit. The absolute humidity in the cabin is specified based on the humidity of the vehicle, and the amount of saturated water vapor of the dust sensor is specified based on the temperature of the dust sensor specified by the sensor temperature specifying unit. The amount of dew condensation generated on the dust sensor is estimated based on the amount of water vapor.

  As described above, when it is determined that the intake mode is the inside air mode, the absolute humidity in the vehicle interior is specified based on the temperature in the vehicle interior and the humidity in the vehicle interior, and the absolute temperature is determined by the sensor temperature specifying unit. By determining the amount of saturated water vapor of the dust sensor based on the temperature of the dust sensor, and estimating the amount of dew condensation generated on the dust sensor based on the absolute humidity of the vehicle interior and the amount of saturated water vapor of the dust sensor, the dew condensation elimination time can be reduced. It can be specified with high accuracy.

(Third embodiment)
A dust concentration detection device according to a third embodiment will be described with reference to FIGS. The outside air temperature, the outside air humidity, the inside air temperature, the inside air humidity, and the door open / close signal are input to the air conditioning control device 40 of the first embodiment. As shown, the outside air temperature and the outside air humidity are input.

  FIG. 13 and FIG. 6 are flowcharts illustrating processing executed by the air conditioning control device 40 and the dust sensor control unit 50 of the present embodiment. 6 are the same as those in the control processing of the first embodiment, the description thereof is omitted here, and the description will focus on the parts shown in FIG.

  As shown in FIG. 13, first, in step S12, the control unit acquires the temperature of the dust sensor 32 detected by the thermistor 325.

  Next, in step S10, the control unit acquires the outside air temperature detected by the outside air temperature sensor, and in step S20, the control unit acquires the outside air humidity detected by the outside air humidity sensor.

  Next, in step S50, the control unit obtains, based on the detection signal from the dust sensor 32, a detection value Dm of the dust concentration detected by the dust sensor 32, that is, a dust concentration detection value Dm. In step S60, the control unit It is determined whether the dew condensation flag is set.

  Here, it is assumed that no condensation has occurred on the dust sensor 32 and the condensation flag has not been set in the storage unit. When the dew condensation flag is not set in the storage unit, the control unit determines in step S63 whether the intake mode is the outside air mode. Specifically, the control unit determines whether the intake mode is the inside air mode or the outside air mode.

Here, when the intake mode is set to the outside air mode, the control unit determines whether or not dew condensation has occurred on the dust sensor 32 in step S80.

  Here, when it is determined that dew condensation has occurred on the dust sensor 32, the control unit specifies the outside air absolute humidity outside the vehicle compartment in step S93. The outside air absolute humidity outside the vehicle compartment can be specified using the outside air temperature acquired in step S10 and the outside air humidity acquired in step S20.

  Next, in step S94, the control unit specifies the saturated water vapor amount of the dust sensor 32. Specifically, the control unit specifies the saturated water vapor amount corresponding to the temperature of the dust sensor 32 acquired in step S10 as the saturated water vapor amount of the dust sensor 32.

Next, in step S110, the control unit estimates the dew condensation amount of the dust sensor 32 based on the outside air absolute humidity outside the vehicle compartment specified in step 93 and the saturated water vapor amount of the dust sensor 32 specified in step S94. . The amount of dew condensation of the dust sensor 32 can be calculated as the volume outside air absolute humidity outside the vehicle compartment minus the saturated water vapor amount of the dust sensor 32. The volume outside air absolute humidity outside the vehicle compartment is the absolute humidity per unit volume, and the unit is expressed as g / m ³ .

  Next, in step S120, the control unit specifies the amount of air around the dust sensor 32. Specifically, the control unit specifies whether the air volume around the dust sensor 32 is large or small.

  Next, in step S130, the control unit specifies the dew condensation elimination time of dust sensor 32. The relationship between the dew condensation elimination time and the amount of dew condensation shown in FIG. 9 is stored in the storage unit of the control unit as a map, and the control unit refers to this map and refers to the dew condensation of the dust sensor 32 identified in step S110. The dew condensation elimination time of the dust sensor 32 is specified based on the amount and the amount of air around the dust sensor 32 specified in step S120. The control unit specifies the dew condensation elimination time of the dust sensor 32 so as to correspond to the air volume around the dust sensor 32 specified in step S120, and proceeds to step S140.

As described above, the dust concentration detection device includes the outside air mode determination unit (S63) that determines whether the intake mode to the ventilation path is the outside air mode for introducing outside air outside the vehicle,
The condensation determining unit determines whether or not condensation has occurred on the dust sensor when the mode determining unit determines that the intake mode is the outside air mode.

  Thus, when it is determined that the intake mode is the outside air mode, it can be determined whether or not dew condensation has occurred on the dust sensor.

  The dust concentration detection device further includes a sensor temperature identification unit that identifies the temperature of the dust sensor 32, an outside air temperature identification unit that identifies the outdoor temperature of the vehicle, and an outdoor humidity identification unit that identifies the outdoor humidity of the vehicle. , Is provided. The dew condensation amount estimating unit is configured to determine, when the mode determining unit determines that the intake mode is the outside air mode, the outdoor temperature of the vehicle specified by the outside air temperature specifying unit and the outdoor temperature of the vehicle specified by the outdoor humidity specifying unit. The absolute humidity outside the vehicle compartment is specified based on the humidity of the vehicle, and the saturated water vapor amount of the dust sensor is specified based on the temperature of the dust sensor specified by the sensor temperature specifying unit. The amount of dew condensation generated on the dust sensor is estimated based on the amount of water vapor.

  As described above, when it is determined that the intake mode is the outside air mode, the absolute humidity outside the vehicle compartment is specified based on the temperature outside the vehicle and the humidity outside the vehicle, and the absolute humidity is specified by the sensor temperature specifying unit. By determining the amount of saturated water vapor of the dust sensor based on the temperature of the dust sensor, and estimating the amount of dew condensation generated on the dust sensor based on the absolute humidity outside the vehicle compartment and the amount of saturated water vapor of the dust sensor, the dew condensation elimination time can be reduced. It can be specified with high accuracy.

(Other embodiments)
(1) In the above embodiments, the outside air temperature is obtained from the outside air temperature sensor, the outside air humidity is obtained from the outside air humidity sensor, the inside air temperature is obtained from the inside air temperature sensor, and the inside air humidity is obtained from the inside air humidity sensor. It is not always necessary to acquire each temperature and each humidity from these sensors. For example, each temperature and each humidity may be acquired via the vehicle LAN. In addition, for example, it may be configured to acquire the outside air temperature and the outside air humidity from a cloud server via a wireless communication network.

  (2) The voltage value for rotating the centrifugal fan 231 of the blower 23 may be varied in multiple stages to vary the wind speed of the air blown from the blower 23 in multiple stages. In this case, the wind speed of the air flowing around the dust sensor 32 may be estimated in multiple stages according to the blower voltage, and the dew condensation elimination time may be specified using the estimated wind speed.

  (3) In the first embodiment, in S70, when the door opening / closing determination unit determines that the door opening of the vehicle has been opened / closed, in S80, it is determined whether or not dew condensation has occurred on the dust sensor. Judgment was made. On the other hand, if it is determined that the vehicle door window has been opened or closed based on the signal indicating whether the vehicle door window has been opened or closed, in S80, it is determined whether or not dew condensation has occurred on the dust sensor. May be determined.

  (4) In the second embodiment, when it is determined that the intake mode is the inside air mode, a dew condensation elimination time suitable for the inside air mode is specified. In the third embodiment, the intake mode is the outside air mode. When the determination is made, the dew condensation elimination time suitable for the outside air mode is specified. On the other hand, the second embodiment and the third embodiment can be combined. Specifically, it is determined whether the intake mode is the inside air mode or the outside air mode, and when the intake mode is the inside air mode, the dew condensation elimination time suitable for the inside air mode is specified. In the case of the outside air mode, the dew condensation elimination time suitable for the outside air mode may be specified.

  Note that the present invention is not limited to the above-described embodiment, and can be appropriately modified within the scope described in the claims. In addition, the above embodiments are not irrelevant to each other, and can be appropriately combined unless a combination is clearly not possible. In each of the above embodiments, it is needless to say that the elements constituting the embodiment are not necessarily essential, unless otherwise clearly indicated as essential or in principle considered to be clearly essential. No. In each of the above embodiments, when a numerical value such as the number, numerical value, amount, range, or the like of the constituent elements of the exemplary embodiment is mentioned, it is particularly limited to a specific number when it is clearly stated that it is indispensable and in principle. The number is not limited to the specific number unless otherwise specified. Further, in each of the above embodiments, when referring to the material, shape, positional relationship, and the like of the components, etc., unless otherwise specified, and unless limited in principle to a specific material, shape, positional relationship, etc. The material, shape, positional relationship, etc. are not limited.

(Summary)
According to a first aspect described in part or all of the above embodiments, the dust concentration detection device includes a light emitting unit that irradiates light and a light receiving unit that receives light. A dust sensor is provided that detects the concentration of dust contained in the air by receiving the reflected light of the irradiated light reflected on the dust contained in the air by the light receiving unit. Also, a dew condensation determining unit that determines whether or not dew condensation has occurred on the dust sensor, and when the dew condensation determining unit determines that dew condensation has occurred on the dust sensor, at least one of the temperature and humidity of the air around the dust sensor And a dew-condensation amount estimating unit for estimating the dew-condensation amount generated in the dust sensor by using the above. Further, a dew condensation elimination time specifying unit that specifies a dew condensation elimination time until the dew condensation generated on the dust sensor is eliminated based on the dew amount estimated by the dew condensation amount estimation unit is provided.

  According to a second aspect, the present dust concentration detection device includes a wind speed estimating unit that estimates a wind speed of air around the dust sensor, and the dew condensation elimination time specifying unit includes a dust sensor estimated by the wind speed estimating unit. The dew condensation elimination time is specified based on the wind speed of the surrounding air and the dew amount estimated by the dew amount estimating unit.

  Therefore, it is possible to specify the dew condensation elimination time in consideration of the influence of the wind speed of the air around the dust sensor.

  According to the third aspect, the dust sensor is disposed in the air-conditioning case having the ventilation passage through which the air blown into the cabin of the vehicle is formed, and detects the concentration of dust contained in the air flowing through the ventilation passage. .

  As described above, it is possible to arrange the dust sensor in the air-conditioning case in which the ventilation passage through which the air blown into the vehicle flows is formed, and to detect the concentration of dust contained in the air flowing through the ventilation passage 24 by the dust sensor. it can.

  According to a fourth aspect, the present dust concentration detection device includes a door opening / closing determination unit that determines whether a door of the vehicle has opened / closed a door opening of the vehicle. When it is determined that the door opening of the vehicle has been opened and closed by the unit, it is determined whether or not dew condensation has occurred on the dust sensor.

  Therefore, when it is determined that the door opening of the vehicle has been opened and closed, it can be determined whether or not dew condensation has occurred on the dust sensor. For example, in a state where the air in the vehicle interior is cooled by cooling, the door of the vehicle opens and closes the door opening, and high-temperature, high-humidity outdoor air outside the vehicle enters the vehicle interior through the vehicle door opening, and the dust sensor In a situation in which dew condensation may occur, it is possible to specify a dew condensation elimination time until the dew condensation generated in the dust sensor is eliminated.

  Further, according to the fifth aspect, the dust concentration detection device includes an outside air absolute temperature specifying unit that specifies an absolute temperature outside the vehicle, a saturated water vapor amount specifying unit that specifies a saturated water vapor amount inside the vehicle, It has. Then, the dew condensation amount estimating unit calculates the amount of dew condensation generated on the dust sensor based on the absolute temperature of the vehicle outdoor specified by the outside air absolute temperature specifying unit and the saturated water vapor amount in the vehicle room specified by the saturated water vapor amount specifying unit. Is estimated.

  As described above, the absolute temperature outside the vehicle and the amount of saturated water vapor inside the vehicle are specified, and the amount of dew condensation generated on the dust sensor is estimated based on the absolute temperature outside the vehicle and the amount of saturated water vapor inside the vehicle. Thus, the condensation elimination time can be specified with high accuracy.

  According to the sixth aspect, the present dust concentration detection device includes an inside air mode determination unit that determines whether the air intake mode to the ventilation path is the inside air mode for introducing inside air in the vehicle compartment. . When the mode determination unit determines that the intake mode is the inside air mode, the condensation determination unit determines whether or not condensation has occurred on the dust sensor.

  Thus, when it is determined that the intake mode is the inside air mode, it can be determined whether or not dew condensation has occurred on the dust sensor.

  According to the seventh aspect, the present dust concentration detection device includes a sensor temperature identification unit that identifies the temperature of the dust sensor, an inside air temperature identification unit that identifies the temperature inside the vehicle, and a humidity detection unit that determines the humidity inside the vehicle. And a room humidity specifying unit for specifying. The dew condensation amount estimating unit is configured to determine, when the mode determining unit determines that the intake mode is the inside air mode, the indoor temperature of the vehicle identified by the indoor air temperature identifying unit and the interior of the vehicle identified by the indoor humidity identifying unit. The absolute humidity in the cabin is specified based on the humidity of the vehicle, and the amount of saturated water vapor of the dust sensor is specified based on the temperature of the dust sensor specified by the sensor temperature specifying unit. The amount of dew condensation generated on the dust sensor is estimated based on the amount of water vapor.

  As described above, when it is determined that the intake mode is the inside air mode, the absolute humidity in the vehicle interior is specified based on the temperature in the vehicle interior and the humidity in the vehicle interior, and the absolute temperature is determined by the sensor temperature specifying unit. By determining the amount of saturated water vapor of the dust sensor based on the temperature of the dust sensor, and estimating the amount of dew condensation generated on the dust sensor based on the absolute humidity of the vehicle interior and the amount of saturated water vapor of the dust sensor, the dew condensation elimination time can be reduced. It can be specified with high accuracy.

  According to the eighth aspect, the present dust concentration detection device includes the outside air mode determination unit that determines whether the air intake mode to the ventilation path is the outside air mode for introducing outside air outside the vehicle. . When the mode determination unit determines that the intake mode is the outside air mode, the condensation determination unit determines whether or not condensation has occurred on the dust sensor.

  Thus, when it is determined that the intake mode is the outside air mode, it can be determined whether or not dew condensation has occurred on the dust sensor.

  According to a ninth aspect, a dust concentration detection device includes a sensor temperature identification unit that identifies a temperature of a dust sensor, an outside air temperature identification unit that identifies an outdoor temperature of a vehicle, and a humidity sensor that detects an outdoor humidity of the vehicle. And an outdoor humidity specifying unit to specify. The dew condensation amount estimating unit is configured to determine, when the mode determining unit determines that the intake mode is the outside air mode, the outdoor temperature of the vehicle specified by the outside air temperature specifying unit and the outdoor temperature of the vehicle specified by the outdoor humidity specifying unit. The absolute humidity outside the vehicle compartment is specified based on the humidity of the vehicle, and the saturated water vapor amount of the dust sensor is specified based on the temperature of the dust sensor specified by the sensor temperature specifying unit. The amount of dew condensation generated on the dust sensor is estimated based on the amount of water vapor.

  As described above, when it is determined that the intake mode is the outside air mode, the absolute humidity outside the vehicle compartment is specified based on the temperature outside the vehicle and the humidity outside the vehicle, and the absolute humidity is specified by the sensor temperature specifying unit. By determining the amount of saturated water vapor of the dust sensor based on the temperature of the dust sensor, and estimating the amount of dew condensation generated on the dust sensor based on the absolute humidity outside the vehicle compartment and the amount of saturated water vapor of the dust sensor, the dew condensation elimination time can be reduced. It can be specified with high accuracy.

  Note that the correspondence between the configuration in the above embodiment and the configuration in the claims will be described. The processing in S80 corresponds to a dew condensation determining unit, the processing in S110 corresponds to a dew condensation amount estimating unit, and the processing in S130 is dew condensation. Corresponds to the cancellation time specifying unit. Further, the process of S120 corresponds to a wind speed estimating unit, the process of S70 corresponds to a door opening / closing determining unit, the process of S90 corresponds to an outside air absolute temperature specifying unit, and the process of S100 corresponds to a saturated water vapor amount specifying unit. , S62 correspond to the inside air mode determination unit. Further, the process of S12 corresponds to a sensor temperature specifying unit, the process of S30 corresponds to an inside air temperature specifying unit, the process of S40 corresponds to an indoor humidity specifying unit, the process of S63 corresponds to an outside air mode determining unit, The process of S10 corresponds to an outside air temperature specifying unit, and the process of S20 corresponds to an outdoor humidity specifying unit.

DESCRIPTION OF SYMBOLS 1 Vehicle air conditioner 21 Air conditioner case 24 Ventilation path 321 Light emitting part 322 Light receiving part 32 Dust sensor 40 Air conditioning controller 50 Dust sensor controller

Claims (9)

A light emitting unit (321) for irradiating light and a light receiving unit (322) for receiving light are provided, and the light receiving unit receives reflected light obtained by reflecting light emitted from the light emitting unit to dust contained in air. A dust sensor (32) for detecting the concentration of dust contained in the air,
A condensation determining section (S80) for determining whether or not condensation has occurred on the dust sensor;
When the dew condensation determining unit determines that dew condensation has occurred on the dust sensor, a dew condensation estimation that estimates a dew condensation amount generated on the dust sensor using at least one of a temperature and a humidity of air around the dust sensor. (S110),
A dust concentration elimination time specifying unit (S130) for specifying a condensation elimination time period until the dew condensation generated on the dust sensor is eliminated based on the dew amount estimated by the dew amount estimating unit; apparatus. A wind speed estimating unit (S120) for estimating a wind speed of the air around the dust sensor;
The dew condensation elimination time specifying unit specifies the dew elimination time based on the wind speed of the air around the dust sensor estimated by the wind speed estimating unit and the dew amount estimated by the dew amount estimating unit. Item 2. The dust concentration detection device according to Item 1.   The dust sensor is disposed in an air-conditioning case (21) having a ventilation path (24) through which air blown into a vehicle room is formed, and detects a concentration of dust contained in the air flowing through the ventilation path. Item 3. The dust concentration detection device according to Item 1 or 2. A door open / close determining unit (S70) for determining whether or not the door of the vehicle has opened / closed a door opening of the vehicle;
4. The dust concentration according to claim 3, wherein when the door opening / closing determining unit determines that the door opening of the vehicle has been opened / closed, the condensation determining unit determines whether or not condensation has occurred on the dust sensor. 5. Detection device. An outdoor-air absolute-temperature specifying unit (S90) for specifying an absolute temperature outside the vehicle; and a saturated water vapor amount specifying unit (S100) for specifying a saturated water vapor amount in the vehicle.
The dew condensation amount estimating unit is configured to detect the absolute temperature of the outside of the vehicle specified by the outside air absolute temperature specifying unit and the amount of saturated water vapor in the vehicle room specified by the saturated water vapor amount specifying unit. The dust concentration detection device according to claim 4, wherein the generated dew amount is estimated. An inside air mode determining unit (S62) for determining whether or not the air intake mode to the ventilation path is an inside air mode for introducing inside air in the room of the vehicle;
4. The dust concentration detection device according to claim 3, wherein when the mode determination unit determines that the intake mode is the inside air mode, the condensation determination unit determines whether or not condensation has occurred on the dust sensor. 5. . A sensor temperature specifying unit (S12) for specifying the temperature of the dust sensor, an inside air temperature specifying unit (S30) for specifying the indoor temperature of the vehicle, and an indoor humidity specifying unit (S40) for specifying the indoor humidity of the vehicle. ) And
The dew condensation amount estimating unit is, when the mode determination unit determines that the intake mode is the inside air mode, specified by the room temperature and the indoor humidity specifying unit of the vehicle specified by the inside air temperature specifying unit. The absolute humidity in the vehicle compartment is specified based on the humidity in the room of the vehicle, and the amount of saturated water vapor of the dust sensor is specified based on the temperature of the dust sensor specified by the sensor temperature specifying unit. The dust concentration detection device according to claim 6, wherein an amount of dew condensation generated in the dust sensor is estimated based on an absolute humidity in the vehicle compartment and a saturated water vapor amount of the dust sensor. An external air mode determining unit (S63) for determining whether the air intake mode to the ventilation path is an external air mode for introducing outdoor air outside the vehicle,
The said condensation determination part determines whether the said intake mode is the said outside air mode by the said mode determination part, and determines whether the dew condensation has generate | occur | produced in the said dust sensor. A dust concentration detection device according to one of the preceding claims. A sensor temperature specifying unit (S12) for specifying the temperature of the dust sensor; an outdoor temperature specifying unit (S10) for specifying the outdoor temperature of the vehicle; and an outdoor humidity specifying unit (S20) for specifying the outdoor humidity of the vehicle. ) And
The dew condensation amount estimating unit, when the mode determining unit determines that the intake mode is the outside air mode, specifies the outdoor temperature of the vehicle specified by the outside air temperature specifying unit and the outdoor humidity specifying unit. The absolute humidity outside the vehicle compartment is specified based on the outside humidity of the vehicle, and the amount of saturated water vapor of the dust sensor is specified based on the temperature of the dust sensor specified by the sensor temperature specifying unit. The dust concentration detection device according to claim 8, wherein an amount of dew condensation generated in the dust sensor is estimated based on an absolute humidity outside the vehicle compartment and a saturated water vapor amount of the dust sensor.

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