JPH0885336A - Air conditioner for vehicle - Google Patents

Abstract

PURPOSE: To actuate a dehumidifying means at a proper timing correctly by calculating an absolute humidity in a vehicle based on a detection value of a humidity sensor, executing dehumidifying operation when the absolute humidity in the vehicle is higher than a specific humidity at saturation, and determining detection of the absolute humidity under specific conditions. CONSTITUTION: In a control device 5 to which output signals of various sensors such as an inner temperature sensor 27, an outer air temperature sensor 28, and an inner relative humidity sensor 29 are inputted, an absolute humidity in a vehicle is calculated, and a specific humidity at saturation of a window glass of the vehicle is calculated. When the calculated inner absolute humidity is higher than the calculated specific humidity at saturation, dehumidifying operation to actuate a dehumidifying means (inner/outer air changing door, for example) is executed. In this case, when the condition where a detection value by the humidity sensor 29 is detected to be a low relative humidity or less occurs, the absolute humidity in the vehicle is calculated and memorized based on the detected humidity value at the time, and the memorized absolute humidity is used as the inner absolute humidity for calculation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention obtains the absolute humidity in the vehicle compartment from the detected value of a humidity sensor in the vehicle interior, and dehumidifies the window glass based on the comparison between this absolute humidity and the saturated absolute humidity in the vehicle window glass. Regarding the air conditioning system for the vehicle,
It is particularly effective when used in an automobile air conditioner.

[0002]

2. Description of the Related Art The air conditioner as described above has been publicly known, and a publicly known technique thereof is, for example, Japanese Patent Laid-Open No. 57-7075.
There is one described in Japanese Patent No. According to this known technique, the window glass surface temperature T1 is first estimated from the vehicle interior temperature and the outside air temperature, and the saturated water vapor pressure P1 is calculated from the estimated temperature T1.
Is being calculated. Further, the vehicle interior water vapor pressure P is calculated from the vehicle interior temperature and the relative humidity inside the vehicle interior. When the vehicle interior water vapor pressure P is larger than a value P1 'which is slightly smaller than the saturated water vapor pressure P1, it is considered that the window glass is fogged and a defrosting device such as a heat ray heater is operated.

[0003]

By the way, the relative humidity in the vehicle compartment is detected by the humidity sensor. Generally, the humidity sensor has a detection limit value on the low humidity side. According to this, as shown in, for example, FIG. 9, the relative humidity of the passenger compartment decreases as the passenger compartment gets warmer in winter, and even if the relative humidity falls below the above limit value, the detected value RHr of the humidity sensor has the above limit value. It remains constant. That is, the actual relative humidity R in the passenger compartment
In the range where Hrt is less than or equal to the above limit value, the relative humidity RHr detected by the humidity sensor becomes higher than the actual relative humidity RHrt, and this difference becomes larger as the vehicle compartment temperature Tr becomes higher.

As a result, in the range where the relative humidity is equal to or lower than the above limit value, the air conditioner control device responds to an increase in the vehicle interior temperature Tr, even though the actual vehicle interior absolute humidity Xrt does not change. Calculate the vehicle interior absolute humidity Xr as a high value. Therefore, for example, when the outside air temperature is low such as 0 ° C. or lower, the temperature of the vehicle window glass is low and the saturated absolute humidity Xgi of the window glass is small. Therefore, it is calculated that the vehicle interior absolute humidity Xr is high as described above. As a result, the vehicle interior absolute humidity Xr exceeds the saturated absolute humidity Xgi, and the dehumidifying means (here, the inside / outside air switching means) may be activated. As a result, there arises a problem that the power saving effect is reduced or the air conditioning balance is lost.

In view of the above problems, the present invention determines the absolute humidity in the vehicle compartment from the detected value of the humidity sensor in the vehicle interior, and dehumidifies the window glass based on the comparison between this absolute humidity and the saturated absolute humidity in the vehicle window glass. In the vehicle air conditioner configured to perform the above, even when the actual relative humidity in the vehicle compartment is lower than the limit value of the humidity sensor, the absolute humidity in the vehicle compartment is calculated as accurately as possible, and thereby the dehumidifying means is operated accurately. It is an object of the present invention to provide an air conditioner that can be used.

[0006]

In order to achieve the above object, the present invention provides a dehumidifying means (9, 15) for dehumidifying a vehicle interior and a humidity for detecting relative humidity in the vehicle interior. A sensor (29), a vehicle interior absolute humidity calculating means (step 250 to step 310) for calculating the absolute humidity in the vehicle compartment based on the detection value of the humidity sensor (29), and a saturated absolute humidity of the vehicle window glass. The saturated absolute humidity calculating means (step 240) and the vehicle interior absolute humidity calculated by the vehicle interior absolute humidity calculating means (step 250 to step 310) are calculated by the saturated absolute humidity calculating means (step 240). Dehumidification control means (step 320, step 330) for operating the dehumidification means (9, 15) when the humidity is higher than the saturated absolute humidity. In the vehicle interior absolute humidity calculating means (step 250 step 310) is, the detected value is a predetermined low relative humidity of the humidity sensor (29) (RH1)
Detection means for detecting the following (step 250)
And when the detection means (step 250) detects that the detection value of the humidity sensor (29) is not lower than the low relative humidity (RH1), the state is detected. Humidity sensor (2
The low humidity absolute humidity calculating means (step 280) for calculating the absolute humidity in the vehicle compartment based on the detection value of 9) and the absolute humidity calculated by the low humidity absolute humidity calculating means (step 280) are stored. Storage means (step 29)
0) and the absolute humidity stored in the storage means (step 290) is calculated as the vehicle interior absolute humidity.

According to a second aspect of the present invention, in the vehicle air conditioner according to the first aspect, the vehicle interior absolute humidity calculating means (steps 250 to 310) is operated by the detecting means (step 250). (2
When it is not detected that the detection value of 9) is lower than the low relative humidity (RH1), the absolute humidity in the vehicle compartment is calculated based on the detection value of the humidity sensor (29). Characterize.

According to a third aspect of the present invention, in the vehicle air conditioner according to any one of the first or second aspects, the vehicle air conditioner is applied to an electric vehicle and blower means (3) for generating an air flow. An air passage (2) for introducing air from the blower means (3) into the vehicle compartment; and the air passage (2)
Inside air intake port (6) for intake of internal air and an outside air intake port (8) for intake of outside air formed in the air upstream side part of the air passage (2).
And the inside air inlet (6) and the outside air inlet (8)
Inlet opening / closing means (9, 15) for selectively opening and closing, and heating means (10, 15) for operating the air in the air passage (2) by operating by electric power supplied from a vehicle running battery (33). 14, 61, 62) and a heating degree control for controlling the air heating degree of the heating means (10, 14, 61, 62) so that the temperature of air blown into the vehicle interior becomes a predetermined target temperature (TAO). Means (step 110 to step 140), the dehumidifying means (9, 15) is constituted by the inlet opening / closing means (9, 15), and the dehumidifying control means (step 320, step 330) is the vehicle. Indoor absolute humidity calculating means (step 250 to step 31)
0) when the vehicle interior absolute humidity is higher than the saturated absolute humidity calculated by the saturated absolute humidity calculating means (step 240), the outside air intake port (8)
Inlet control means for controlling the inlet opening / closing means (9, 15) so as to increase the opening ratio (step 32).
0, step 330).

The predetermined low relative humidity referred to in the invention of claim 1 means a detection limit value on the low humidity side of the humidity sensor or a value slightly larger than the detection limit value. Further, the reference numerals in the parentheses indicate the correspondence with the concrete means of the embodiments described later.

[0010]

According to the present invention, the vehicle interior absolute humidity calculating means calculates the vehicle interior absolute humidity on the basis of the detection value of the humidity sensor, and the vehicle interior absolute humidity is the saturated absolute value. The dehumidification control means operates the dehumidification means when the saturated absolute humidity calculated by the humidity calculation means is higher.

If the relative humidity inside the vehicle is equal to or higher than the predetermined low relative humidity, the humidity sensor can detect the relative humidity almost accurately. Calculates the absolute humidity in the passenger compartment almost accurately. Therefore, dehumidification control by comparing the absolute humidity with the saturated absolute humidity is performed almost accurately. On the other hand, when the relative humidity inside the vehicle is less than or equal to the low relative humidity,
The humidity sensor cannot accurately detect this relative humidity, and the detection value of the humidity sensor remains constant at the low relative humidity. Therefore, at this time, even if the vehicle interior temperature rises, the detected value of the humidity sensor remains constant at the low relative humidity, so that the absolute humidity calculated by the absolute humidity calculating means does not actually change. Regardless, it rises as the passenger compartment temperature rises.

Therefore, in the present invention, when the detected value of the humidity sensor changes from the above-mentioned low relative humidity state to the following state,
The low humidity absolute humidity calculation means calculates the vehicle interior absolute humidity based on the humidity sensor value at this time, and the storage means stores it. Then, the vehicle interior absolute humidity calculating means calculates the absolute humidity stored in the storage means as the vehicle interior absolute humidity, and the dehumidification control means operates the dehumidifying means based on the comparison between the vehicle interior absolute humidity and the saturated absolute humidity. .

Since the absolute humidity stored in the storage means is a humidity calculated based on the humidity sensor value when the detected value of the humidity sensor changes from a state above the low relative humidity to the following state, it is almost accurate. Absolute humidity in the passenger compartment.
Therefore, by setting the stored absolute humidity as the vehicle interior absolute humidity, the vehicle interior absolute humidity can be calculated almost accurately even when the vehicle interior relative humidity is equal to or lower than the low relative humidity. And thereby, a dehumidification means can be operated correctly.

According to the second aspect of the present invention, when the detection means does not detect that the detection value of the humidity sensor is equal to or lower than the low relative humidity, that is, when the detection value of the humidity sensor is equal to or higher than the low relative humidity. Since the humidity sensor can detect the relative humidity in the vehicle compartment almost accurately, the vehicle interior absolute humidity calculating means calculates the vehicle interior absolute humidity based on the detection value of the humidity sensor. This makes it possible to accurately calculate the vehicle interior absolute humidity over a wider range and to operate the dehumidifying means accurately.

In particular, the invention according to claim 3 heats the air blown into the passenger compartment based on the electric power supplied from the vehicle running battery of the electric vehicle, and when the absolute humidity in the passenger compartment is higher than the saturated absolute humidity. An air conditioner for an electric vehicle that increases the amount of intake of outside air. Therefore, as described above, the absolute humidity inside the vehicle is accurately calculated, and the absolute humidity inside the vehicle is accurately compared with the saturated absolute humidity to eliminate the wasteful increase control of the intake amount of outside air and to reduce the power consumption in the heating means. By eliminating wasteful consumption, it is very effective in terms of power saving.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, one embodiment of the present invention will be described with reference to FIGS. First, the overall configuration of this embodiment will be described with reference to FIG. The air conditioner 1 includes a duct 2 that guides blown air into the passenger compartment, a blower unit 3 that introduces air into the duct 2 and sends the air into the passenger compartment, an accumulator-type refrigeration cycle 4, and an air conditioner controller 5.

An inside air suction port 6 and an outside air suction port 8 are formed on the air upstream side of the duct 2. Further, an inside / outside air switching door 9 is provided between the inside air inlet 6 and the outside air inlet 8 so as to be rotatable between a solid line position and a broken line position in the figure. When the inside / outside air switching door 9 is in the solid line position in the figure, the outside air is introduced into the duct 2, and when it is in the broken line position in the figure, the inside air is sucked into the duct 2. Further, the inside / outside air switching door 9 is opened / closed by an opening / closing drive means 15 (specifically, a servomotor) for the door.

At the end of the duct 2 on the downstream side of the air, a defroster outlet 2a for blowing blast air toward the window glass of the vehicle, a face outlet 2b for blowing blast air toward the upper body of the occupant, and the feet of the occupant A foot outlet 2c that blows blown air toward the front is formed. Each of the outlets 2a to 2c is selectively opened and closed by an outlet switching door (not shown) that operates according to the outlet mode.

The refrigeration cycle 4 comprises a compressor 10, an outdoor heat exchanger 11, a cooling decompression means 12, a heating decompression means 13,
The indoor heat exchanger 14, the accumulator 16, and the four-way valve 17 as the refrigerant flow path switching means are respectively provided with the refrigerant pipe 31.
Connected by the well-known. The compressor 10 sucks, compresses, and discharges the refrigerant, and is driven by an electric motor 32 (see FIG. 3) incorporated therein. The electric motor 32 is driven by receiving electric power from the vehicle running battery 33 (see FIG. 3), and the rotation speed is determined according to the frequency variably controlled by the inverter 19. Therefore, the refrigerant discharge capacity of the compressor 10 is equal to the electric motor 32.
Changes according to the rotation speed of.

The outdoor heat exchanger 11 is a heat exchanger which is disposed outside the duct 2 (outside the vehicle compartment) and receives air from the outdoor fan 20 to exchange heat between the outdoor air and the refrigerant. The outdoor heat exchanger 11 functions as a condenser during a cooling operation described later, and functions as an evaporator during a heating operation described later. The cooling decompression means 12 decompresses and expands the refrigerant from the outdoor heat exchanger 11 during the cooling operation, and is specifically configured by a capillary tube.

The heating decompression means 13 decompresses and expands the refrigerant from the indoor heat exchanger 14 during the heating operation, and is specifically composed of a capillary tube. The indoor heat exchanger 14 is arranged inside the duct 2 and is provided with the blower 3
The heat exchanger exchanges heat between the air in the duct 2 and the refrigerant by receiving the air blown from. The indoor heat exchanger 14 functions as an evaporator during cooling operation and as a condenser during heating operation.

The accumulator 16 temporarily stores the excess refrigerant in the refrigeration cycle 4 and sends out only the gas refrigerant so that the compressor 10 does not suck the liquid refrigerant.
Further, the refrigeration cycle 4 is provided with a bypass passage bypassing the cooling decompression means 12 and a bypass passage bypassing the heating decompression means 13, and the check valve 24 and the check valve in the middle of each bypass passage. 23 are provided.

The four-way valve 17 switches the flow of the refrigerant as follows depending on the cooling operation and the heating operation. (During cooling operation) The high temperature and high pressure refrigerant discharged from the compressor 10 is
The four-way valve 17-> the outdoor heat exchanger 11-> the check valve 23-> the cooling decompression means 12-> the indoor heat exchanger 14-> the four-way valve 17-> the accumulator 16-> the compressor 10 (indicated by arrow C in the figure). Thereby, the indoor heat exchanger 14 functions as an evaporator, and the air in the duct 2 is cooled by the indoor heat exchanger 14.

(During heating operation) The high-temperature high-pressure refrigerant discharged from the compressor 10 is supplied to the four-way valve 17 → indoor heat exchanger 14 → check valve 2
4-> depressurizing means 13 for heating-> outdoor heat exchanger 11-> four-way valve 1
Flow in the order of 7 → accumulator 16 → compressor 10 (indicated by arrow H in the figure). Thereby, the indoor heat exchanger 14 functions as a condenser, and the air in the duct 2 is heated by the indoor heat exchanger 14.

Next, the control device 5 will be described. As shown in FIG. 3, the control device 5 has interfaces 51, C.
A blower means that incorporates a microcomputer including a PU 52, a ROM 53, a RAM 54, and the like, based on an operation signal output from the air conditioner operation panel 25, a sensor signal from each of the sensors 26 to 31 described later, and a signal from the wiper switch 32. 3, outdoor fan 20, four-way valve 17,
The servomotor 15 and other actuators are energized and controlled.

As each of the above-mentioned sensors, a solar radiation sensor 26 for detecting the amount of solar radiation Ts applied to the vehicle interior, an indoor temperature sensor 27 for detecting the vehicle interior temperature Tr, and an outside air temperature Tam.
Temperature sensor 28 for detecting the temperature, relative humidity RH in the passenger compartment
The indoor relative humidity sensor 29 for detecting r, the pressure sensor 30 for detecting the refrigerant pressure Pc ′ on the discharge side of the compressor 10, and the suction temperature sensor 31 for detecting the air temperature Tin on the suction side of the indoor heat exchanger 14 are used. Has been.

Next, the operation of the air conditioner control device 5 for controlling the rotation speed of the compressor 10 during the heating operation will be described with reference to the flowchart shown in FIG. First, step 1
At 00, the air conditioner operation panel 25, each sensor 26 to
31 and the signal from the wiper switch 32 are read. Next, at step 110, the air conditioner operation panel 25
From the set temperature Tset in the vehicle compartment set in step 1 and the values of the respective sensors (vehicle interior temperature Tr, outside air temperature Tam, insolation Ts), the target outlet temperature of the air blown into the vehicle compartment ( (Hereinafter referred to as TAO).

[0028]

## EQU1 ## TAO = Kset × Tset−Kr × Tr−Kam ×
Tam-Ks * Ts + C Here, Kset, Kr, Kam, and Ks are gains, respectively, and C is a correction constant. Then step 120
From the above TAO and suction temperature Tin, the saturated refrigerant temperature Tc is calculated based on the following mathematical formula 2.

[0029]

## EQU00002 ## Tc = (TAO-Tin) /. Phi. (V) + Tin Here, .phi. (V) is a temperature efficiency which varies depending on the air volume V of the blowing means 3, and the relationship between this temperature efficiency .phi. (V) and the air volume V is This is as shown in FIG. The data shown in this FIG.
It is stored in M53.

Then, in step 130, RO
Based on the data shown in FIG. 6 stored in M53, the saturation pressure Pc corresponding to the saturated refrigerant temperature Tc calculated in step 120 is obtained. Then, in step 140, a rotation speed control signal is output to the inverter 19 to control the rotation speed of the compressor 10 so that Pc 'detected by the pressure sensor 30 becomes the saturation pressure Pc.

That is, the compressor 10 to the indoor heat exchanger 14
Since the pressure loss up to is small, the saturation pressure Pc can be regarded as substantially equal to the discharge pressure (= Pc ') of the compressor 10. Therefore, the saturated refrigerant temperature Tc calculated in step 120 can be obtained by controlling the rotation speed of the compressor 10 so that Pc ′ becomes Pc, and as a result, the temperature of the air blown into the vehicle interior is changed to the target air blow temperature ( TAO).

Next, the air conditioner control device 5 for performing anti-fog control
The operation will be described with reference to the flowchart shown in FIG. First, in step 200, a flag FLAG to be described later is
Is set to 0. Next, at step 210, it is judged if the wiper switch 32 is on. That is, it is determined whether it is raining.

When it is determined that the wiper switch 32 is turned on, the window glass inner surface temperature Tgi is calculated in step 220 based on the following mathematical formula 3.

[0034]

## EQU3 ## Tgi = 0.04Tf + 0.03Tr + 0.93Tam Here, Tf is a temperature indicating the temperature of the air blown from the defroster outlet 2a, and is calculated backward from the value of the pressure sensor 30 using the relationship of FIG. It is calculated as a value obtained by subtracting the heat loss in the duct 2 from the measured temperature. In this way, the temperature of air blown out from the defroster outlet 2a is obtained from the value of the pressure sensor 30. The above-mentioned blown air temperature has a correlation with the temperature of the indoor heat exchanger 14, and by extension, the value of the pressure sensor 30. Because. Further, the mathematical formula 3 and the mathematical formula 4 described later are formulas that are derived assuming that the vehicle speed is 100 km / h.

If it is determined in step 210 that the wiper switch 32 is not on, step 230
Then, the window glass inner surface temperature Tgi is calculated based on the following Equation 4.

[0036]

## EQU00004 ## Tgi = 0.13Tf + 0.11Tr + 0.76Tam Then, in the next step 240, the window glass inner surface temperature T calculated in the above step 220 or step 230.
The saturated absolute humidity Xgi corresponding to gi is calculated from the relationship shown in FIG. The relationship shown in FIG. 7 is generally called a moist air diagram, and is based on the assumption that the relative humidity is 100%. In addition, this relationship is previously stored in the ROM 53.
Remembered in.

Next, at step 250, it is judged if the detected value RHr of the relative humidity sensor 29 is less than or equal to a preset set value RH1. Here, the set value RH1 is the detection limit value RHmin of the relative humidity sensor 29 on the low humidity side.
It is a slightly higher value (RH1 = RHmin + α). If YES is determined here, it is determined in the next step 260 whether or not the flag is 0. This FLAG is step 20
Since it is cleared at 0, when the process of step 260 is executed for the first time after the operation of the air conditioner control device 5 is started, it is determined to be YES, and at the next step 270, FL is set.
Set AG = 1.

Then, in the next step 280, the relative humidity is 100% from the relationship between the vehicle interior air temperature Tr and the relationship shown in FIG.
At this time, the absolute humidity Xr 'in the vehicle compartment is obtained, and the detected value of the relative humidity sensor 29 is calculated from the Xr' and the detected value RHr of the relative humidity sensor 29 based on the following equation 5.
The absolute humidity Xr1 in the vehicle compartment at the time when the following is obtained is calculated.

[0039]

[Formula 5] Xr1 = Xr '× RHr / 100 × 10 ^-3 (kg
Then, in the next step 290, this Xr1 is set as the absolute humidity Xr used in step 320 described later. Also,
Even when the detection value RHr of the relative humidity sensor 29 is equal to or less than the set value RH1 and YES is determined in step 250, if the determination of YES is the second time or later, NO in the next step 260. Is determined (because FLAG = 1 is set at step 270 at the first time), and at step 290, step 2 at the first time is performed.
The absolute humidity Xr1 calculated in 80 is the absolute humidity Xr in the vehicle compartment.
And

On the other hand, when NO is determined in step 250, FLAG = 0 is set in step 300,
In the next step 310, the vehicle interior absolute humidity Xr is calculated based on the following equation 6 by the same calculation method as in step 280.

[0041]

## EQU6 ## Xr = Xr '× RHr / 100 × 10 ^-3 (kg
/ Kg ') Then, in the next step 320, it is determined whether or not Xr> 0.9Xgi. Then, if YES, it is considered that the window glass is likely to be fogged, and the servo motor 15 is controlled in step 330 so that the outside air introduction amount increases. If NO, it is considered that the window glass is not easily fogged, and the servo motor 15 is controlled in step 340 so that the outside air introduction amount is reduced.

Here, in step 320, it is not determined whether Xr> Xgi, but it is determined whether Xr> 0.9Xgi because the window glass is anti-fog. Even if the amount of introduced outside air is increased, the antifogging effect does not immediately appear, so that it is possible to allow the antifogging control to have a margin by determining whether or not Xr> 0.9Xgi.
However, it may be determined whether or not Xr> Xgi. In short, in steps 320 and 330,
The external air introduction amount may be increased when Xr is larger than Xgi.

Also, step 330 and step 340
Then, the outside air introduction amount is controlled to change by 25%. Note that each of the above steps constitutes means for realizing each function. According to the above control, the vehicle interior temperature rises due to the warm-up control at a low outside temperature such as when the outside air temperature is 0 ° C. or less, and the detection value RHr of the relative humidity sensor 29 decreases accordingly. When the set value becomes RH1 or less, the vehicle interior absolute humidity Xr1 at the time when it becomes RH1 or less is set as the vehicle interior absolute humidity Xr used in step 320.

When the detected value RHr becomes less than or equal to RH1 (when it is first determined as YES in step 250)
The vehicle interior absolute humidity Xr1 is the value when the relative humidity sensor 29 is still accurately detecting the vehicle interior relative humidity, and while the determination in step 250 is NO, the detected value RHr at the above point Since the absolute humidity Xr1 calculated based on step 320 is used in the subsequent step 320, step 320
It is possible to make the determination based on the almost accurate absolute humidity in the vehicle compartment.

Therefore, in step 330, it is possible to prevent the compressor 10 from unnecessarily increasing the amount of outside air introduced and wastefully consuming electric power, and the power saving effect is enhanced. In other words, if cold outside air is introduced, the indoor heat exchanger 14
Temperature of the air upstream of the compressor 1 decreases, which increases the heating load on the indoor heat exchanger 14 and increases the compressor 1
Although the power consumption of 0 is large, this embodiment does not unnecessarily increase the amount of outside air introduced, so the power saving effect is improved.

If NO in step 250, that is, if the relative humidity sensor 29 can accurately detect the relative humidity in the vehicle compartment, then step 2 is performed.
While YES is determined in step 50, step 310 is performed.
To the detected value RHr of the relative humidity sensor 29 at that time.
Based on this, the absolute humidity Xr in the vehicle compartment is calculated, and the determination in step 320 is performed based on this Xr.

As described above, in this embodiment, the absolute humidity in the vehicle compartment can be accurately calculated not only while the determination is NO at step 250 but also when the determination is YES thereafter. At this time, in step 300, FL
Since AG is set to 0, as in the case where the air conditioner is started, when the state is determined to be YES again from the state determined to be NO in step 250, step 2
While YES is determined in step 50, the subsequent step 3 is performed based on the vehicle interior absolute humidity Xr1 calculated at this time.
The antifogging determination at 20 is performed.

In the case of the above control, once the detected value RHr of the relative humidity sensor 29 becomes less than or equal to the set value RH1, the vehicle interior absolute humidity is always calculated to be a constant value until the detected value RHr exceeds the set value RH1 again. However, in a normal situation, the interior of the vehicle is not suddenly heated, so there is no problem even if the constant value is set as described above. (Other Embodiments) In the above embodiment, the indoor heat exchanger 14 functions as a condenser to heat the air blown into the vehicle interior, but the air is not necessarily heated directly in the indoor heat exchanger 14. No need. For example, as shown in FIG. 8, a heater core 61 as a heater may be provided in the duct 2 and the hot water flowing into the heater core 61 may be heated by the heat of condensation in the refrigeration cycle 4.

That is, in this embodiment, the refrigerant-hot water heat exchanger 62 exchanges heat between the condensation heat of the refrigerant flowing in the heat exchanger 62 and the hot water in the hot water pipe 63 to heat the hot water. . Then, the heated hot water is introduced into the heater core 61, and the heater core 6 is driven by the air mix doors 64 and 65.
By adjusting the amount of air flowing into 1, the air outlet 2a ~
The temperature of the air blown from 2c is adjusted to an appropriate temperature.

In this embodiment, in addition to the warm water heating by the heat of condensation, the combustion heater 66 also heats the warm water. The combustion heater 66 heats hot water by burning the fuel in the combustion tank 67. The amount of hot water heated by the combustion heater 66 and the amount of hot water heated by the heat of condensation are adjusted by hot water valves 68 and 69.

In the present embodiment, the temperature of the air passing through the heater core 61 is indirectly detected based on the detection value of the water temperature sensor 70 as the hot water temperature detecting means installed on the hot water pipe 63. Here, since the temperature of the heater core 61 is directly related to the detection value of the water temperature sensor 70, if the heat exchange efficiency in the heater core 61 and the opening degrees of the air mix doors 64 and 65 are taken into consideration, the defroster outlet 2a.
It is possible to uniquely determine the temperature of the air blown from the.

[Brief description of drawings]

FIG. 1 is a flowchart showing a main part of an embodiment of the present invention.

FIG. 2 is an overall configuration diagram of the above embodiment.

FIG. 3 is a block diagram of a control system of the above embodiment.

FIG. 4 is a control flowchart of the above embodiment.

FIG. 5 is a graph showing the relationship between the air volume V and the temperature efficiency φ (V).

FIG. 6 is a graph showing the relationship between saturation temperature Tc and high pressure Pc.

FIG. 7 is a graph showing the relationship between temperature and absolute humidity.

FIG. 8 is an overall configuration diagram of another embodiment of the present invention.

FIG. 9 is a diagram illustrating a reason why a conventional dehumidifying unit malfunctions.

[Explanation of symbols]

 1 Air Conditioner 2 Duct (Air Passage) 3 Blower Means 4 Refrigeration Cycle 5 Control Device 6 Inside Air Intake Port 8 Outside Air Intake Port 9 Inside / Outside Air Switching Door (Dehumidifying Means, Inlet Opening / Closing Means) 14 Indoor Heat Exchanger (Heating Means) 29 Relative humidity sensor (humidity sensor) 61 Heater core (heating means) 62 Refrigerant-hot water heat exchanger (heating means)

Claims (3)

[Claims] 1. Dehumidifying means for dehumidifying the vehicle interior, a humidity sensor for detecting relative humidity in the vehicle interior, and vehicle interior absolute humidity calculating means for calculating the absolute humidity in the vehicle interior based on the detection value of the humidity sensor. The saturated absolute humidity calculating means for calculating the saturated absolute humidity of the vehicle window glass, and the vehicle interior absolute humidity calculated by the vehicle interior absolute humidity calculating means is more than the saturated absolute humidity calculated by the saturated absolute humidity calculating means. When the temperature is high, in a vehicle air conditioner including a dehumidifying control unit that operates the dehumidifying unit, the vehicle interior absolute humidity calculating unit detects that the detection value of the humidity sensor is equal to or lower than a predetermined low relative humidity. And a detection unit that detects that the detection value of the humidity sensor is lower than or equal to the low relative humidity by the detection unit. A low humidity absolute humidity calculating means for calculating the absolute humidity in the vehicle compartment based on the detected value of the humidity sensor at the time, and a storage means for storing the absolute humidity calculated by the low humidity absolute humidity calculating means. A vehicle air conditioner configured to calculate the absolute humidity stored in the storage means as the vehicle interior absolute humidity. 2. The vehicle interior absolute humidity calculating means, when the detecting means does not detect that the detected value of the humidity sensor is equal to or lower than the low relative humidity, the vehicle interior based on the detected value of the humidity sensor. The vehicle air conditioner according to claim 1, wherein the vehicle air conditioner is configured to calculate the absolute humidity of the. 3. The air conditioner for a vehicle is applied to an electric vehicle, an air blower for generating an air flow, an air passage for guiding air from the air blower into a passenger compartment, and an air upstream side portion of the air passage. An external air intake port for intake of external air, an internal air intake port for intake of internal air formed in an air upstream side portion of the air passage, and the external air intake port and the internal air intake port are selectively Inlet opening / closing means for opening / closing, heating means for heating the air in the air passage by operating by the electric power supplied from the vehicle running battery, and the temperature of the air blown into the vehicle interior to a predetermined target temperature. A heating degree control means for controlling an air heating degree of the heating means, the dehumidifying means is constituted by the inlet opening / closing means, and the dehumidifying control means is controlled by the vehicle interior absolute humidity calculating means. Inhalation for controlling the inlet opening / closing means so as to increase the rate of opening the outside air inlet when the vehicle interior absolute humidity calculated by the above is higher than the saturated absolute humidity calculated by the saturated absolute humidity calculating means. The vehicle air conditioner according to claim 1 or 2, wherein the air conditioner comprises a mouth control unit.