JP2012116276A - Vehicle air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicle air conditioner which properly determines that windshield is fogged and ensures antifogging performance and fuel economy.SOLUTION: An air-conditioning control means (32) of a control means (30) includes: a glass vicinity temperature calculating means (41) for calculating a temperature of air near windshield (2) in a vehicle cabin; a glass vicinity dew-point temperature calculating means (42) for calculating a dew-point temperature of the air near the windshield (2) in the vehicle cabin, on the basis of the temperature of the air near the windshield (2) in the vehicle cabin and a relative humidity; a windshield temperature calculating means (43) for calculating a windshield temperature; and a window-fogging determining means (44) for determining a fogging state of the windshield (2) in the vehicle cabin (3), on the basis of the dew-point temperature of the air near the windshield (2) in the vehicle cabin and the windshield temperature.

Description

  The present invention relates to a vehicle air conditioner, and more particularly to a vehicle air conditioner that performs dehumidification heating in a vehicle interior to control air conditioning in the vehicle interior.

2. Description of the Related Art In recent years, development of electric vehicles (hereinafter referred to as “vehicles”) such as electric vehicles and hybrid vehicles is increasing as automobiles focusing on fuel efficiency. In such a vehicle air conditioner, if the air conditioning state is sufficiently comfortable, in order to improve fuel efficiency, the driving of the air conditioning compressor is stopped and the heat source supply of the heater core is stopped (for example, idling stop). Etc. can be controlled.
Further, from the viewpoint of anti-fogging properties, when the inner surface of the windshield is cloudy (hereinafter referred to as “window fogging”), even in a comfortable air-conditioning state, dehumidification of the air in the passenger compartment (drive of the air conditioning compressor) and The window fogging should be cleared by heating the windshield (securing the heat source with the heater core).
From the above description, it is necessary to determine the window fogging state by air conditioning control in order to ensure fuel saving and anti-fogging properties.

Japanese Patent No. 3633034 JP-A-9-118118

The vehicle air conditioner according to Patent Document 1 determines window fogging based on a temperature difference between the dew point temperature of the passenger compartment air and the windshield temperature, and calculates the dew point temperature based on the air temperature and the relative humidity. The dew point temperature is calculated based on the air temperature in the vehicle compartment and the inside air relative humidity detected by the inside air temperature detecting means.
The automotive air conditioner according to Patent Document 2 calculates a glass dew point temperature based on the glass near air temperature detected by the inside air temperature detecting means.

By the way, conventionally, in the above-mentioned Patent Document 1, as shown in FIG. 9, the inside air temperature detecting means 102 and the inside air humidity detecting means 103 are installed on the instrument panel 101 and detected by the inside air temperature detecting means 102. There is a temperature difference between the inside air temperature and the air temperature near the inner surface of the windshield 105 (indicated by the region R) that is the boundary between the inside of the vehicle (the cabin 104) and the outside of the vehicle (the air temperature in the vicinity of the windshield 105). And the air dew point temperature in the vicinity of the inner surface of the windshield 105 (glass dew point temperature) do not become the same value, so that an error occurs between the window fogging prediction and the actual window fogging behavior, thus preventing fogging and fuel saving. Sex could not be secured. In FIG. 9, reference numeral 106 denotes a steering wheel, and 107 denotes an in-vehicle mirror.
That is, in the above-mentioned Patent Document 1, window fog is determined by Trd−Tw ≧ α.
Here, Trd is the inside air dew point temperature, and is calculated from the inside air temperature detected by the inside air temperature detecting means 102 of the instrument panel 101 and the inside air relative temperature detected by the inside air humidity detecting means 103. Tw is the windshield temperature, and is estimated and calculated from the outside air temperature, the vehicle speed, and the like. α is a constant value (a numerical value is determined based on experimental data).
If Trd−Tw ≧ α is “true”, it is determined that there is window fogging (implementing air conditioning control such as dehumidification), and if Trd−Tw ≧ α is “false”, it is determined that there is no window fogging. To do.
On the other hand, window fogging is determined by the temperature difference between the dew point temperature of the air near the inner surface of the windshield 104 (glass near dew point temperature) and the windshield temperature. If Tnd> Tw is “true”, window fogging occurs. .
Here, Tnd is a glass near dew point temperature. Tw is the windshield temperature.
However, there is a temperature difference between the air temperature (inside air temperature) of the inside air temperature detecting means 102 of the instrument panel 101 and the air temperature (in the vicinity of the glass) in the vicinity of the inner surface of the windshield, which is the boundary between the inside and outside of the vehicle, and the inside air dew point temperature. (Trd) and near glass dew point temperature (Tnd) do not become the same value (in this case, it is assumed that the inside air relative humidity is constant in the passenger compartment). For this reason, even if Trd−Tw ≧ α is “true”, there is a possibility that the window fogging judgment and the actual window fogging behavior do not match such that Tnd> Tw becomes “false”. (See FIG. 10).

  In Patent Document 2, a temperature sensor, a harness for securing an installation location, and a connection with an air conditioning control means are required to detect the temperature in the vicinity of the inner surface of the windshield. There was an inconvenience.

  Accordingly, an object of the present invention is to provide a vehicle air conditioner that can ensure anti-fogging properties and fuel saving performance by improving the determination accuracy when the windshield is actually fogged.

  The present invention provides a vehicle air conditioner that performs dehumidification heating based on the air temperature and relative humidity in the vehicle interior to control the air conditioning of the vehicle interior, and includes an inside air relative humidity detection means that detects the relative humidity in the vehicle interior, A glass vicinity temperature calculating means for calculating an air temperature in the passenger compartment near the glass, and an air temperature in the passenger compartment near the windshield calculated by the glass vicinity temperature calculating means and the passenger compartment detected by the inside air relative humidity detecting means. Calculated by the glass near dew point temperature calculating means for calculating the dew point temperature of the vehicle interior air near the windshield based on the relative humidity of the windshield, the windshield temperature calculating means for calculating the windshield temperature, and the glass near dew point temperature calculating means. The dew point temperature of the passenger compartment air near the windshield and the windshield temperature calculated by the windshield temperature calculating means Characterized in that a control means that includes a window fogging determining means for determining cabin cloudy state of the front glass on the basis of the scan temperature.

  The vehicle air conditioner according to the present invention makes it possible to ensure antifogging properties and fuel efficiency by improving the determination accuracy when the windshield is actually fogged.

FIG. 1 is a control block diagram of the vehicle air conditioner. (Example) FIG. 2 is a system configuration diagram of the vehicle air conditioner. (Example) FIG. 3 is a flowchart of a method for calculating the windshield temperature. (Example) FIG. 4 is a diagram for calculating β by the outlet (MODE). (Example) FIG. 5 is a diagram for calculating γ according to the air volume. (Example) FIG. 6 is a flowchart of a method for calculating the dew point temperature near the windshield. (Example) FIG. 7 is a flowchart of a method for determining window fogging. (Example) FIG. 8 is a diagram for explaining the window fogging determination accuracy state of the present invention as compared with the prior art. (Example) FIG. 9 is a diagram for explaining the position of each detecting means and the window fogging position in the prior art. (Conventional example) FIG. 10 is a diagram for explaining a conventional window fogging determination state. (Conventional example)

  The purpose of this invention is to improve the determination accuracy when the windshield is actually fogged, thereby ensuring anti-fogging properties and fuel efficiency. This is realized by determining the cloudiness of the windshield in the passenger compartment based on the above.

1 to 8 show an embodiment of the present invention.
In FIG. 2, 1 is a vehicle equipped with an engine and an electric motor, 2 is a windshield of the vehicle 1, 3 is a passenger compartment, and 4 is a vehicle air conditioner (air conditioner: HVAC unit) mounted in the vehicle 1.
The vehicle air conditioner 4 performs dehumidification heating based on the air temperature and relative humidity in the passenger compartment 3 to control the air conditioning of the passenger compartment 3, and includes a passage forming body 6 that forms an air circulation passage 5. I have.
The passage forming body 6 includes an inside / outside air that swings inward so as to switch between an outside air introduction port 8 connected to the outside air introduction duct 7 and an inside air introduction port 10 connected to the inside air introduction duct 9 at one end on the upstream side. A switching damper 11, a suction port actuator 12 that operates the inside / outside air switching damper 11, a defroster outlet 14 connected to the defroster duct 13 at the other end on the downstream side, and a vent outlet 16 connected to the vent duct 15. Connected to the foot duct 19 at the other end on the downstream side, the first blower outlet switching damper 17 that swings inward to switch, the first mode actuator 18 that operates the first blower switching damper 17 A second air outlet switching damper 21 that swings inward so as to open and close the foot air outlet 20 to be opened, and a second mode actuator that operates the second air outlet switching damper 21. And Yueta 22 is provided.

Further, in the passage forming body 6, a blower fan 23 on the downstream side of the inside / outside air switching damper 11, an evaporator 24 on the downstream side of the blower fan 23, a heater core 25 on the downstream side of the evaporator 24, An air mix damper 26 that swings in the air circulation passage 5 so as to adjust an air flow rate to the heater core 25 and an AM actuator 27 that operates the air mix damper 26 are provided.
The blower fan 23 includes a fan motor 28 that drives the blower fan 23, and supplies cooled air into the passenger compartment 3. The heater core 25 is driven to heat the passenger compartment 3.
The vehicle air conditioner 4 is provided with an air conditioning compressor 29 that is driven by electricity or an engine and used for cooling the passenger compartment 3. The air conditioning compressor 29 is used when the user manually operates, and is driven for the purpose of dehumidification.

The vehicle air conditioner 4 is provided with a control means (ECU) 30 for performing air conditioning control by signals from various operation states and various detection means.
The control means 30 includes an engine control means 31 and an air conditioning control means 32.
The engine control means 31 communicates with the air conditioning compressor 29 and also communicates with the air conditioning control means 32 via a communication means 33 such as CAN communication.
As shown in FIG. 1, the air-conditioning control means 32 has an input side that detects an outside air temperature detecting means 34, an inside air temperature detecting means 35 that detects the air temperature in the passenger compartment 3, and the amount of solar radiation. The solar radiation amount detecting means 36 for detecting, the vehicle speed detecting means 37 for detecting the speed of the vehicle 1, the inside air relative humidity detecting means 38 for detecting the relative humidity in the passenger compartment 3, and the operation state of the wiper of the vehicle 1 are detected. It communicates with the wiper operation detection means 39 and the air conditioning operation panel 40 provided with various switches. On the output side, the suction port actuator 12, the first mode actuator 18, the second mode actuator 22, and the AM actuator are provided. 27 and a fan motor 28 of the blower fan 23.

Further, as shown in FIG. 1, the air-conditioning control means 32 is calculated by the glass vicinity temperature calculation means 41 for calculating the air temperature in the passenger compartment 3 near the windshield 2 and the glass vicinity temperature calculation means 41. The vicinity of the glass that calculates the dew point temperature of the passenger compartment air in the vicinity of the windshield 2 based on the air temperature in the passenger compartment 3 in the vicinity of the windshield 2 and the relative humidity in the passenger compartment 3 detected by the inside air relative humidity detecting means 38. The dew point temperature calculating means 42, the windshield temperature calculating means 43 for calculating the temperature of the windshield 2, and the dew point temperature of the passenger compartment air near the windshield 2 and the windshield temperature calculated by the glass vicinity dew point temperature calculating means 42 A window fogging judgment hand for judging the presence or absence of a fogged state in the passenger compartment 3 of the windshield 2 based on the windshield temperature calculated by the means 43 It includes a 44, a clouding state determining means 45 determines the presence or absence of a state fogging window determined in the window fogging determining means 44.
The air-conditioning control unit 32 includes a blowout temperature storage unit 46, a blowout port (MODE) storage unit 47, and an air volume storage unit 48 in communication with the windshield temperature calculation unit 43.

Further, the glass vicinity temperature calculating means 41 communicates with the inside air temperature detecting means 35 for detecting the air temperature in the passenger compartment 3, and the air temperature in the passenger compartment 3 detected by the inside air temperature detecting means 35 and the windshield temperature. Based on the windshield temperature calculated by the calculation means 43, the air temperature in the passenger compartment 3 near the windshield 2 is calculated.
As a result, the air temperature in the passenger compartment near the windshield 2 can be obtained by using detection means mounted on a general vehicle without adding a separate temperature sensor in the passenger compartment 3 in the vicinity of the windshield 2. Can do.

Next, a method for calculating the windshield temperature in the windshield temperature calculating means 43 will be described.
As shown in FIG. 3, when the program starts (step A01), first, temperature 1 is calculated (step A02). This temperature 1 is calculated by calculation such as regression analysis using signals from each detection means such as the outside air temperature detection means 34.
That is, temperature 1 is
Temperature 1 = f (outside air temperature, inside air temperature, vehicle speed, solar radiation amount)
Is required.
Then, it is determined whether the wiper is activated and the wiper operation detecting means 39 is turned on (step A03).
If this step A03 is YES, the temperature 2 is set to α (° C.) (temperature 2 = α (° C.)) (step A04). This temperature 2 assumes a decrease in the temperature of the windshield 2 during rainy weather, and when the wiper operation detection means 39 is on (while the wiper is being driven), α (α <0 (° C.)). Is set.
However, if this step A03 is NO, the temperature 2 is set to 0 (° C.) (temperature 2 = 0 (° C.)) (step A05).
After the processing of step A04 or after the processing of step A05, the temperature 3 is calculated as a value obtained by adding the temperature 2 to the temperature 1 (temperature 3 = temperature 1 + temperature 2) (step A06).
Then, the windshield temperature calculating means 43 calculates the windshield temperature (step A07).
The windshield temperature in this step A07 is calculated based on the temperature 1, the temperature 2, and the blowing temperature from each blowing outlet, and is an intermediate value between the temperature 3 (temperature 1 + temperature 2) and the blowing temperature. Therefore, it is calculated as follows.
Windshield temperature = temperature 3+ (blowing temperature−temperature 3) × β × γ
Here, β is a value set by the outlet (MODE) (see FIG. 4). γ is a value set by the air volume (see FIG. 5). Β and γ vary in the range of 0 to 1. For example, as shown in FIG. 4, β is calculated according to each outlet, and is set larger as the outlet having a higher air distribution rate to the windshield 2. As shown in FIG. 5, γ is set according to the air volume, and varies in the range of 0 ≦ γ ≦ 1.
In the calculation of the windshield temperature described above, the blowout temperature, the blowout opening, and the air volume are general control calculation items when performing air conditioning control.
Then, after the process of step A07, the program is returned (step A08).

Next, a method for calculating the windshield near dew point temperature in the glass near dew point temperature calculating means 42 will be described.
As shown in FIG. 6, when the program starts (step B01), first, the temperature near the windshield is calculated (step B02).
The windshield vicinity temperature in this step B02 is calculated by regression analysis or the like from the windshield temperature calculated in FIG. 3 and the inside air temperature.
In other words, the temperature near the windshield is
Windshield vicinity temperature = f (windshield temperature, inside air temperature)
Is calculated by
Then, the windshield near dew point temperature is calculated by the glass near dew point temperature calculating means 42 (step B03).
The dew point in the vicinity of the windshield in step B03 is calculated based on the wet wind diagram from the windshield near temperature and the inside air relative humidity (detected by the inside air humidity detecting means 38) (assuming that the inside air relative humidity is constant in the passenger compartment). Calculated based on This wet air diagram is generally used in the field of air conditioning control.
Then, after the processing of step B03, the program is returned (step B04).

Next, a method for determining the presence or absence of window fogging in the window fog determination means 44 will be described.
As shown in FIG. 7, when the program starts (step C01), first, the temperature difference is
Temperature difference = winding glass near dew point temperature−winding glass temperature is calculated (step C02).
Then, it is determined whether or not the temperature difference ≧ α (step C03).
When this step C03 is YES, it is assumed that there is window fogging (step C04), and as air conditioning control for clearing the window fogging, driving of the air conditioning compressor 29, driving of the engine from the idle stop (heat source securing by the heater core 25) ) Etc. are implemented.
However, if this step C03 is NO, it is assumed that there is no window fogging (step C05), and the control is not performed.
After the process of step C04 or after the process of step C05, the program is returned (step C06).
As shown in FIG. 8, it is clear that the actual window fogging determination accuracy in this embodiment (the present invention) is improved as compared with the prior art.

  As a result, in this embodiment, the accuracy of determination when the windshield 2 is actually fogged can be improved, and the operation of the vehicle air conditioner 4 can be performed without defogging function due to the fog determination. Since time can be saved, anti-fogging properties and fuel efficiency can be ensured.

In the present invention, the temperature of the windshield can be detected by installing a temperature sensor on the surface of the windshield.
Further, the temperature near the windshield can be calculated by map data determined by a conformance test in addition to the regression analysis.
Furthermore, it is also possible to obtain a calculation formula for the temperature near the windshield from a desktop calculation such as numerical fluid analysis.

  The vehicle air conditioner according to the present invention can be applied to electric vehicles such as electric vehicles and hybrid vehicles, and various vehicles.

DESCRIPTION OF SYMBOLS 1 Vehicle 2 Windshield 3 Car compartment 4 Vehicle air conditioner 5 Air distribution passage 23 Blower fan 25 Heater core 29 Air conditioning compressor 30 Control means 31 Engine control means 32 Air conditioning control means 34 Outside air temperature detection means 35 Inside air temperature detection means 36 Solar radiation amount detection means 37 Vehicle speed detection means 38 Inside air relative humidity detection means 39 Wiper operation detection means 40 Air-conditioning operation panel 41 Glass vicinity temperature calculation means 42 Glass vicinity dew point temperature calculation means 43 Windshield temperature calculation means 44 Window fogging determination means

Claims (2)

  In a vehicle air conditioner that performs dehumidification heating based on the air temperature and relative humidity in the passenger compartment to control the air conditioning of the passenger compartment, an internal air relative humidity detecting means for detecting the relative humidity in the passenger compartment is provided, and the vehicle near the windshield is provided. A near-glass temperature calculating means for calculating an indoor air temperature, an air temperature in the vehicle interior near the windshield calculated by the near-glass temperature calculating means, and a relative humidity in the vehicle interior detected by the inside air relative humidity detecting means Based on the above, the near-glass dew point temperature calculating means for calculating the dew point temperature of the passenger compartment air near the windshield, the windshield temperature calculating means for calculating the windshield temperature, and the windshield calculated by the near glass dew point temperature calculating means The dew point temperature of the vehicle interior air in the vicinity and the windshield temperature calculated by the windshield temperature calculation means Air conditioning system, characterized in that a control means that includes a window fogging determining means for determining cabin cloudy state of the front glass Zui.   The glass vicinity temperature calculating means communicates with the inside air temperature detecting means for detecting the air temperature in the vehicle interior, and the air temperature in the vehicle interior detected by the inside air temperature detecting means and the front glass temperature calculated by the windshield temperature calculating means. 2. The vehicle air conditioner according to claim 1, wherein the air temperature in the passenger compartment near the windshield is calculated based on the glass temperature.

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