JPH10203135A - Air-conditioning device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent formation of frost on an evaporator when a device is in a low outside air temperature area by clarifying the preferable arrangement position of a cooling degree detecting means. SOLUTION: An air-conditioning unit 1 is formed such that partition plate 20 is provided to partition the interior of an air-conditioning case 2 into a first air passage 18 to suck internal air and a second air passage 19 to suck outside air and an inside sand outside air two-layer mode is provided. A first after-evaporator temperature sensor 55 is arranged in a first air passage 18 situated right downstream from an evaporator 15 and a second after-evaporator temperature sensor 56 is arranged in a second air passage 19 situated right downstream from the evaporator 15. Based on an after-evaporator temperature on the low temperature side of a first after-evaporator temperature on the inside air side detected by the first after-evaporator temperature sensor 55 and the second after-evaporator temperature on the outside air side detected by the second after-evaporator temperature sensor 56, ON/OFF of a compressor 11 is decided by an ECU.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a first air passage through which the interior of an air-conditioning case is blown into a vehicle cabin from a foot outlet through a vehicle interior air sucked from an interior air suction port, and the exterior of the vehicle compartment sucked from an outside air suction port. The present invention relates to a vehicle air conditioner including a partition member that partitions air into a second air passage that blows air from a defroster outlet into a vehicle interior.

[0002]

2. Description of the Related Art A first air conditioner for a vehicle as described above.
As a conventional technique, there is a technique disclosed in Japanese Patent Application Laid-Open No. 5-124426. Briefly describing the configuration of the first prior art, an air conditioning case of a vehicle air conditioner has an inside air inlet and an outside air inlet formed at one end, and a foot outlet, a defroster outlet, and A face outlet is formed.

[0003] The interior space of the air-conditioning case is divided into a first air passage through which a compartment air (hereinafter referred to as inside air) is blown into the vehicle interior from a foot air outlet by a partition plate and an outside air suction port. A second air passage that blows out the sucked outside air (hereinafter referred to as outside air) from the defroster outlet into the vehicle interior is defined. And, inside the air conditioning case, a blower that generates an air flow,
An evaporator for cooling the air and a heater core for heating the air are provided.

[0004] When the foot differential mode is selected as the outlet mode, the internal air is introduced into the first air passage and the outside air is introduced into the second air passage. The interior of the vehicle heats the interior of the vehicle to improve the heating performance, and the low-humidity outside air blows out to the inner surface of the window glass, thereby improving the anti-fog performance of the window glass.

A second prior art is disclosed in Japanese Patent Application Laid-Open No. 7-4 / 1995.
There is a technique disclosed in Japanese Patent No. 7831. In the configuration of the second related art, an inside air suction port and an outside air suction port are formed at one end of the air conditioning case, as in the first related art.
A foot outlet, a defroster outlet, and a face outlet are formed at the other end. In the internal space of the air-conditioning case, a first air passage and a second air passage having a structure similar to that of the above-described first related art are defined by a partition plate, and a blower, an evaporator, and the like are provided in the air-conditioning case. A heater core is provided. Furthermore, the second prior art describes that a post-evaporation temperature sensor for detecting an air temperature (post-evaporation temperature) immediately after passing through an evaporator is provided.

[0006]

However, neither the first nor the second prior art describes a specific arrangement position of the post-evaporation temperature sensor. Therefore, the following experiments were performed for the case where the post-evaporation temperature sensor was provided on the first air passage side and the case where the post-evaporation temperature sensor was provided on the second air passage side. That is, when the post-evaporation temperature sensor is provided on the first air passage side, the experimental temperature sensor is provided immediately after the evaporator on the second air passage side, and the post-evaporation temperature sensor is provided on the second air passage side. For, an experimental temperature sensor was provided immediately after the evaporator on the first air passage side.

When the post-evaporation temperature detected by the post-evaporation temperature sensor is equal to or higher than the first predetermined temperature (for example, 4 ° C.), cooling is performed by the evaporator, and the post-evaporation temperature detected by the post-evaporation temperature sensor is set to the second predetermined temperature ( When the control to stop the cooling by the evaporator at a temperature of 3 ° C. or less is performed under various outside air temperatures, an experiment is performed to determine what the post-evaporation temperature detected by the above-described experimental temperature sensor is. Was done. As a result, the data shown in FIG. 13 is obtained in the case where the post-evaporation temperature sensor is provided on the first air passage side where the inside air flows, and the post-evaporation temperature sensor is provided on the second air passage side where the outside air mainly flows. In this case, the data shown in FIG. 14 was obtained.

From these data, it can be seen that when a post-evaporation temperature sensor is provided on the side of the second air passage, FIG.
As shown in (2), when the outside air temperature is in the low outside air temperature range of 10 ° C. or less, the temperature of the cold air on the first air passage side is much higher than the second predetermined temperature. Accordingly, when the operating state of the evaporator is controlled based on the post-evaporation temperature on the second air passage side, the post-evaporation temperature on the first air passage side becomes the second predetermined temperature in the low outside air temperature range. Since the operation of the evaporator is stopped before the temperature is lowered, the dehumidifying performance of the inside air on the first air passage side is reduced. Therefore, there arises a problem that the inner surface of the window glass is easily fogged.

When a post-evaporation temperature sensor is provided on the side of the first air passage, as shown in FIG. 13, the dehumidifying performance can be ensured in each of the first and second air passages. The temperature after evaporation on the side of the second air passage in the low outside air temperature range of not more than ° C is lower than the second predetermined temperature.
Accordingly, when the operation state of the evaporator is controlled based on the post-evaporation temperature on the first air passage side, the post-evaporation temperature on the second air passage side becomes the second predetermined temperature in the low outside air temperature range. Since the operation of the evaporator will be continued even if the temperature is lower than the temperature, there is a possibility that the evaporator on the second air passage side is frosted (frosted). Therefore, the resistance (ventilation resistance) of the air passing through the evaporator on the side of the second air passage increases, and the amount of air blown toward the inner surface of the window glass decreases, so that a problem occurs that the anti-fog performance of the window glass decreases. .

[0010]

SUMMARY OF THE INVENTION It is an object of the present invention to clarify a preferable arrangement position of a cooling degree detecting means to prevent a decrease in dehumidifying performance in a low outside air temperature range or prevent frost formation on a cooling heat exchanger. It is an object of the present invention to provide an air conditioner for a vehicle that can be operated.

[0011]

According to the first aspect of the present invention, the first cooling degree detecting means is disposed in the first air passage of the air conditioning case, and the second cooling degree is detected in the second air passage. By arranging the means, it is possible to detect both the air cooling degree on the first air passage side and the air cooling degree on the second air passage side. Thereby, the operation and stop of the cooling heat exchanger can be controlled based on at least one of the air cooling degree on the first air passage side and the air cooling degree on the second air passage side. .

As a result, if the inside air temperature of the vehicle interior air sucked into the first air passage is higher than the outside air temperature, and the outside air temperature of the vehicle outside air sucked into the second air passage is in a low outside air temperature range, Even in this case, the operation of the cooling heat exchanger is harder to stop compared with the cooling air temperature detector provided only on the second air passage side, and a decrease in the dehumidifying performance of the vehicle interior air can be suppressed. it can. Further, the operation of the cooling heat exchanger is less likely to be continued than in the case where the cooling degree detecting means is provided only on the first air passage side, and the frost formation of the cooling heat exchanger on the second air passage side is reduced. Can be suppressed. Therefore, it is possible to suppress an increase in the humidity of the air blown into the vehicle interior, so that the inner surface of the window glass is hardly fogged, and it is possible to suppress a decrease in the amount of air blown into the vehicle interior, so that the anti-fog performance of the window glass is reduced. Can be suppressed.

According to the second aspect of the present invention, if the first
The inside air temperature of the vehicle interior air sucked into the first air passage from the suction port is higher than the outside air temperature, and the outside air temperature of the vehicle outside air sucked into the second air passage from the second suction port is in a low outside air temperature range. Even at this time, similarly to the first aspect of the invention, it is possible to suppress a decrease in the dehumidifying performance of the vehicle interior air and to suppress the formation of frost on the cooling heat exchanger on the second air passage side. it can. Therefore, it is possible to suppress an increase in the humidity of the air blown out from the first outlet toward the feet of the occupant of the vehicle, so that the inner surface of the window glass is less likely to fog, and
Since the decrease in the amount of air blown out from the outlet toward the window glass can be suppressed, a decrease in the anti-fog performance of the window glass can be suppressed.

According to the third aspect of the invention, the air temperature in the first air passage immediately after passing through the cooling heat exchanger or the air in the second air passage immediately after passing through the cooling heat exchanger. Since the operation state of the cooling heat exchanger can be controlled based on at least one of the air temperatures,
An effect similar to that of the first aspect is obtained.

According to the fourth aspect of the invention, the air temperature on the first air passage side immediately after passing through the cooling heat exchanger or the air temperature on the second air passage side immediately after passing through the cooling heat exchanger. When any one of the temperatures is equal to or higher than the first predetermined temperature, the cooling heat exchanger is operated. Further, one of the air temperature on the first air passage side immediately after passing through the cooling heat exchanger and the air temperature on the second air passage side immediately after passing through the cooling heat exchanger is: First
When the temperature is equal to or lower than the second predetermined temperature lower than the predetermined temperature, the operation of the cooling heat exchanger is stopped. Thereby, the same effect as that of the first aspect can be obtained.

According to the fifth aspect of the invention, the air temperature on the first air passage side immediately after passing through the cooling heat exchanger or the air temperature on the second air passage side immediately after passing through the cooling heat exchanger. When the correction temperature obtained by adding the influence of one of the temperatures to the other air temperature is equal to or higher than the first predetermined temperature, the cooling heat exchanger is operated. Further, the air temperature of one of the air temperature of the first air passage immediately after passing through the cooling heat exchanger and the air temperature of the second air passage immediately after passing through the cooling heat exchanger is set to the other air temperature. When the correction temperature to which the influence of the air temperature is applied is equal to or lower than the second predetermined temperature, the operation of the cooling heat exchanger is stopped. Thereby, the same effect as that of the first aspect can be obtained.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION

[Configuration of First Embodiment] FIGS. 1 to 9 show a first embodiment of the present invention.
FIG. 1 shows an embodiment, and FIG. 1 is a diagram showing an entire configuration of a ventilation system of an air conditioner for a vehicle.

In the vehicle air conditioner of the present embodiment, each air conditioning unit of the air conditioning unit 1 for air conditioning the interior of a vehicle equipped with, for example, a diesel engine (hereinafter referred to as an engine) is used as an air conditioning control device (hereinafter referred to as an ECU). 9) An automatic air conditioner configured to automatically control the temperature in the vehicle cabin to always maintain the set temperature by controlling the air conditioner 9.

First, the configuration of the air conditioning unit 1 will be described with reference to FIG. The air-conditioning unit 1 is mounted on the vehicle such that the upper part in the drawing is the front of the vehicle (engine side), the lower part in the drawing is the rear part of the vehicle (inside the vehicle compartment), and the left-right direction in the drawing is the vehicle width direction. An air-conditioning case 2 forming an air passage for guiding air is provided. The air-conditioning case 2 is formed of a resin material such as polypropylene, and is configured by connecting the inside / outside air switching means, the blower 8, the cooler unit, and the heater unit in order from the air upstream side. Note that broken lines X and Y in FIG. 1 indicate these binding sites. The inside / outside air switching means and the blower 8 will be described later.

In the cooler unit, an evaporator (refrigerant evaporator) 15 is provided, which is one component of the refrigeration cycle 10 mounted on the vehicle. The refrigeration cycle 10 includes a compressor (refrigerant compressor) 11 that compresses refrigerant by the driving force of an automobile engine, a condenser (refrigerant condenser) 12 that condenses and liquefies the compressed refrigerant, and a gas-liquid refrigerant that condenses and liquefies the refrigerant. A receiver (gas-liquid separator) 13 for separating and flowing only the liquid refrigerant downstream, an expansion valve (expansion valve, decompression means) 14 for decompressing and expanding the liquid refrigerant, and the evaporator 15 for evaporating the decompressed and expanded refrigerant. It is composed of

The evaporator 15 is a component corresponding to the cooling heat exchanger of the present invention, and is disposed so as to penetrate a partition plate 20 described later so as to entirely cover the inside of the air-conditioning case 2 and pass therethrough. It performs an air cooling function of cooling air to be cooled and an air dehumidifying function of dehumidifying air passing therethrough.
That is, the evaporator 15 is connected to the first air passage 1 described later.
A first cooling unit for cooling air flowing through the inside 8 and a second cooling unit
And a second cooling unit that cools the air flowing through the air passage 19.

The compressor 11 is connected with an electromagnetic clutch 16 for interrupting transmission of rotational power from the engine to the compressor 11. This electromagnetic clutch 16
Is energized, the rotational power of the engine is transmitted to the compressor 11, the air cooling action is performed by the evaporator 15, and the energization of the electromagnetic clutch 16 is stopped.
The engine and the compressor 11 are shut off, and the air cooling action by the evaporator 15 is stopped.

An evaporator 15 is provided in the heater unit.
Is provided with a heater core 17 for reheating the cold air that has passed through. As shown in FIGS. 2 and 3, the heater core 17 is disposed such that the cool air forms bypass passages 18 a and 19 a that bypass the heater core 17, and cooling water for cooling the engine flows therein, A heating heat exchanger for reheating cold air using the cooling water as a heating heat source. Further, the heater core 17 is provided so as to partially penetrate a width direction or a height direction of the air conditioning case 2 in the air conditioning case 2 through a partition plate 20 described later,
It comprises a first heating unit for heating air flowing in the first air passage 18 described later and a second heating unit for heating air flowing in the second air passage 19 described later.

On the air upstream side of the heater core 17, rotating shafts 3a, 4a are provided rotatably with respect to the air conditioning case 2. And the plate-like first,
The second air mix doors 3, 4 are integrally connected. Servo motors 39 and 40 (see FIG. 5) as driving means are connected to the rotating shafts 3a and 4a. Then, the rotary shaft 3 is driven by the servo motors 39 and 40.
The first and second air mix doors 3 and 4 are rotated from the solid line position in FIGS. 2 and 3 to the dashed line position in FIGS. That is, the first and second air mix doors 3 and 4 can be moved depending on their stop positions.
By adjusting the ratio between the amount of cool air passing through the heater core 17 and the amount of warm air passing through the first and second bypass passages 18a and 19a, the air conditioner functions as a blowout temperature adjusting means for adjusting the blowout temperature of the air blown into the vehicle interior.

The cooler unit and the heater unit are connected as a connecting means by, for example, a claw fitting or a screw member. In the cooler unit and the heater unit, as shown in FIG. 1, a partition plate 20 extending in a substantially vertical direction allows a first air passage (inner air passage) 18 through which mainly air flows and an outer air mainly. A flowing second air passage (outside air passage) 19 is defined. Further, the evaporator 15, the heater core 17, and the rotating shafts 3a, 4a are disposed over the first air passage 18 and the second air passage 19.

The first air passage 18 blows vehicle interior air (hereinafter referred to as inside air) sucked from a first inside air suction port 5a, which will be described later, through a foot (FOOT) opening 2a into a vehicle interior from a foot outlet. It is a ventilation path. The second air passage 19 receives the outside air (hereinafter referred to as outside air) sucked from an outside air intake port 5c, which will be described later, through a defroster (DEF) opening 2b and a face (FACE) opening 2c. This is a ventilation path that blows out into the vehicle interior from the face outlet and side face outlet.

The partition plate 20 is a part corresponding to the partition member of the present invention, and is interrupted at a position slightly upstream from the most downstream of the air conditioning case 2 and downstream of the heater core 17.
A communication hole 20a that connects the first air passage 18 and the second air passage 19 is formed at the discontinuous portion. The communication hole 20a is opened and closed by a foot door described later.

At the most downstream end of the air conditioning case 2, F
An OOT opening 2a, a DEF opening 2b, and a FACE opening 2c are formed. And the FOOT opening 2
a is connected to a foot duct (not shown),
Warm air is mainly blown out from the foot outlet (corresponding to the first outlet of the present invention) which is the most downstream end of the foot duct toward the feet of the occupant. A defroster duct (not shown) is connected to the DEF opening 2b.
Warm air is mainly blown from the defroster outlet (corresponding to the second outlet of the present invention), which is the most downstream end of the defroster duct, toward the inner surface of the front shield glass. Further, a center face duct and side face ducts (both not shown) are connected to the FACE opening 2c. Of these, the conditioned air introduced into the center face duct is blown out toward the occupant's head and chest from the center face outlet, which is the most downstream end of the center face duct. Further, the conditioned air introduced into the side face duct is blown from the side face outlet, which is the most downstream end of the side face duct, toward the inner surface of the side shield glass.

A foot door 21, a defroster door 22, and a face door 23 are provided on the upstream side of each of the openings 2a to 2c. The foot door 21 is an air outlet switching door that opens and closes an air inflow passage to the foot duct, the defroster door 22 is an air outlet switching door that opens and closes an air inflow passage to the defroster duct, and the face door 23 is a door opening to the center face duct. This is an air outlet switching door that opens and closes the air inflow passage to the air inflow passage.

The doors 21 to 23 are connected by a link mechanism (not shown), and the link mechanism is driven by a servo motor 41 (see FIG. 5) as a driving means. That is, when the servomotor 41 moves the link mechanism, the doors 21 to 23 move so as to obtain the outlet modes described later. Also,
The air inflow passage to the side face duct is
２３23 does not open or close. An outlet grill (not shown) is provided in the vicinity of the side face outlet to allow the occupant to manually open and close the side face outlet, and the air inflow passage to the side face duct is opened and closed by the outlet grill.

Next, the configuration of the inside / outside air switching means and the blower 8 will be described with reference to FIG. Here, FIG. 4 is a schematic perspective view seen from the arrow C direction in FIG. The inside / outside air switching means is for taking in at least one or both of the inside air and the outside air into the air conditioning case 2 as shown in FIG. And first and second suction port switching doors 6 and 7 rotatably mounted in the inside / outside air switching box 5. Inside the inside / outside air switching box 5, a blower 8 for generating an airflow toward the vehicle interior is provided. The inside / outside air switching box 5 is formed with a first inside air suction port (corresponding to a first suction port of the present invention) 5a corresponding to the first suction port 8a of the blower 8, and the second suction port of the blower 8 is provided. A second inside air suction port 5b and an outside air suction port (corresponding to the second suction port of the present invention) 5c are formed corresponding to the port 8b.

The first inlet switching door 6 is connected to the first inside air inlet 5.
The second suction port switching door 7 is a door that opens and closes the second inside air suction port 5b and the outside air suction port 5c. The first and second suction port switching doors 6 and 7 are connected to servo motors 42 and 43 (see FIG. 5) as respective driving means.
2 and 43, respectively, are rotated between a solid line position and a dashed line position in the figure. The inside / outside air switching box 5 includes:
A communication path 30 that connects the second inside air suction port 5b or the outside air suction port 5c with the first suction port 8a is formed. Then, the first suction port switching door 6 fully closes the communication path 30 when the first inside air suction port 5a is fully opened (the position indicated by the solid line in FIG. 4),
The communication passage 30 is fully opened when the first inside air suction port 5a is fully closed (in a position indicated by a chain line in FIG. 4).

The blower 8 is a component corresponding to the blower of the present invention, and is disposed substantially at the center of the inside / outside air switching box 5. The blower 8 includes a first fan 31, a second fan 32, and a blower motor 33 for driving the first and second fans 31, 32 to rotate. Here, first,
The second fans 31 and 32 are integrally formed, and the first
The diameter of the second fan 32 is larger than the diameter of the fan 31. And these first and second fans 31, 32 are
The air suction side is housed in first and second scroll casing portions 34 and 35 each having a bell mouth shape. These first and second scroll casing portions 3
The end portions (air blowing side) of Nos. 4 and 35 are the first,
It communicates with the second air passages 18 and 19. First,
The second scroll casing portions 34 and 35 are divided into partition portions 36.
Is shared.

Next, the configuration of the control system of this embodiment will be described with reference to FIG. Here, FIG. 5 is a block diagram showing a control system of the air conditioner for a vehicle. Switch signals from switches on an operation panel 37 provided on the front of the vehicle compartment are input to an ECU (corresponding to the air conditioning control means of the present invention) 9 for controlling each air conditioning means of the air conditioning unit 1.
Here, the switches on the operation panel 37 include, for example, an air conditioner switch 50 for instructing start and stop of the refrigeration cycle 10, a temperature setting switch for the occupant to set a vehicle interior set temperature, and a suction mode. Switch for switching the air outlet mode, a switch for switching the air volume of the first and second fans 31, 32, and an auto switch for instructing the automatic control of each air conditioner. Switch.

It should be noted that even during the automatic control, each air conditioner is controlled by giving priority to switch signals from the air conditioner switch 50, the suction port changeover switch, the air outlet changeover switch and the air volume changeover switch. The suction port changeover switch includes an outside air introduction switch for fixing the inside air introduction mode and an inside air circulation switch for fixing the inside air circulation mode. Further, a face switch for fixing to a face (FACE) mode, a bi-level switch for fixing to a bi-level (B / L) mode, and a foot for fixing to a foot (FOOT) mode are included in the air outlet switch. There are a switch, a foot differential switch for fixing to a foot differential (F / D) mode, and a face switch for fixing to a defroster (DEF) mode.

The ECU 9 has an inside air temperature sensor 51 for detecting the air temperature (inside air temperature) in the vehicle interior, an outside air temperature sensor 52 for detecting the air temperature outside the vehicle interior (outside air temperature), and solar radiation irradiated into the vehicle interior. Insolation sensor 53 for detecting the amount of water, and water temperature sensor 5 for detecting the temperature of the cooling water flowing into heater core 17
4. A first post-evaporation temperature sensor 55 for detecting the degree of air cooling on the first air passage 18 immediately after the evaporator 15, and a second evaporator for detecting the degree of air cooling on the second air passage 19 immediately after the evaporator 15. Each sensor signal from the rear temperature sensor 56 is input.

The first post-evaporation temperature sensor 55 includes:
A component corresponding to the first cooling degree detecting means of the present invention, specifically, detecting the air temperature (first post-evaporation temperature, inside air post-evaporation temperature) of the first air passage 18 immediately after passing through the evaporator 15. A first temperature detecting means such as a thermistor. Further, the second post-evaporation temperature sensor 56 is the second post-evaporation temperature sensor 56 of the present invention.
A component corresponding to the cooling degree detecting means. Specifically, similarly to the first post-evaporation temperature sensor 56, the air temperature in the second air passage 19 immediately after passing through the evaporator 15 (the second post-evaporation temperature, the outside air After the temperature)
It is a temperature detecting means.

A well-known microcomputer including a CPU, a ROM, a RAM, and the like (not shown) is provided inside the ECU 9, and signals from the sensors 51 to 56 are supplied to an A / A by an input circuit (not shown) in the ECU 9. D
After being converted, it is configured to be input to a microcomputer. The ECU 9 is supplied with power from a battery (not shown) when an ignition switch (not shown) of the vehicle engine is turned on.

Next, a control process of the microcomputer according to the present embodiment will be described with reference to FIGS. Here, FIG. 6 is a flowchart showing the control processing by the microcomputer.

First, when the ignition switch is turned on (ON) and power is supplied to the ECU 9, the routine shown in FIG. 6 is started, and initialization and initialization are performed (step S1). Subsequently, the set temperature set by the temperature setting switch is read (step S2). Subsequently, signals obtained by A / D conversion of the sensor signals from the inside temperature sensor 51, the outside temperature sensor 52, the solar radiation sensor 53, the water temperature sensor 54, and the first and second post-evaporation temperature sensors 55 and 56 are read (step S3). ).

Subsequently, the target blowing temperature (TAO) of the air blown into the vehicle compartment is calculated based on the following equation (1) stored in the ROM beforehand (step S4).

## EQU1 ## TAO = Kset × Tset−Kr × Tr−K
am × Tam−Ks × Ts + C where Tset is the temperature set by the temperature setting switch,
r is the inside air temperature detected by the inside air temperature sensor 51, Tam is the outside air temperature detected by the outside air temperature sensor 52, and Ts is the amount of solar radiation detected by the solar radiation sensor 53. Also, Kset,
Kr, Kam and Ks are gains, and C is a correction constant.

Subsequently, a blower voltage (voltage applied to the blower motor 33) corresponding to the target blowing temperature (TAO) is obtained from a characteristic diagram (map) (not shown) stored in the ROM in advance.
Is determined (step S5). Subsequently, an outlet mode corresponding to the target outlet temperature (TAO) is determined from a characteristic diagram (map) (not shown) stored in the ROM in advance (step S6). Here, in determining the outlet mode,
The target blowing temperature (TAO) is determined to be in the FACE mode, the B / L mode, the FOOT mode, and the F / D mode from a low temperature to a high temperature.

In the FACE mode, the foot door 2
1 is a mode in which the air conditioning air is blown toward the occupant's head and chest in the passenger compartment with the dashed line position in FIG. 1, the defroster door 22 set in the solid line position, and the face door 23 set in the dashed line position. In the B / L mode, the foot door 21 and the defroster door 22 are set to the solid line position in FIG. 1 and the face door 23 is set to the dashed line position to direct the conditioned air toward the occupant's head and chest and feet in the passenger compartment. This is a blowing mode.

In the FOOT mode, the foot door 21 and the face door 23 are set in the solid line position in FIG. 1, the defroster door 22 is set in the position in which the DEF opening 2b is slightly opened, and about 80% of the air-conditioned air is set in the vehicle interior. In this mode, the air blows toward the feet of the occupant and about 20% of the conditioned air is blown toward the inner surface of the front shield glass. In the F / D mode, the foot door 21 is set to a solid line position in FIG. 1, the defroster door 22 is set to a dashed line position, and the face door 23 is set to a solid line position. In this mode, the same amount is blown out.

In this embodiment, when the defroster switch provided on the operation panel 37 is operated, the foot door 21 and the defroster door 22 are set to the solid line position in FIG. 1, and the deface door 23 is set to the solid line position in FIG. A DEF mode in which wind is blown toward the inner surface of the front shield glass is also set. In any of the outlet modes, the side face outlet can be opened and closed by an outlet grill.

Subsequently, a subroutine shown in FIG. 9 is called to perform frost control. Specifically, the post-evaporation temperature T
The operation and stop of the compressor 11 are controlled based on E (frost control means: step S7). Subsequently, based on the following equation 2 previously stored in the ROM, the first,
The target door opening (SW) of the second air mix doors 3, 4 is calculated (step S8).

## EQU2 ## SW = {(TAO-TE) / (TW-TE)}
× 100 (%) Note that TE is the value of steps S32 and S33 in FIG.
The post-evaporation temperature (correction temperature) and TW determined in S36 and S38 are the cooling water temperature detected by the water temperature sensor 54.

When SW ≦ 0 (%) is calculated, the first and second air mixing doors 3 and 4 allow all of the cool air from the evaporator 15 to pass through the first and second bypass passages 1 and 2.
It is controlled to the position (MAXCOOL position) that passes through 8a and 19a. Furthermore, when it is calculated as SW ≧ 100 (%), the first and second air mix doors 3 and 4 are controlled to a position (MAXHOT position) where all of the cool air from the evaporator 15 passes through the heater core 17. And 0
(%) <SW <100 (%)
The first and second air mixing doors 3 and 4 are provided with an evaporator 1
5 is controlled to a position where the cool air from 5 flows through both the heater core 17 and the first and second bypass passages 18a and 19a.

Subsequently, control processing for determining the suction port mode is performed. That is, the subroutine shown in FIG. 7 is called, and the set positions of the first and second suction port switching doors 6, 7 are determined (step S9). Subsequently, control signals are output to the blower motor 33 and the servomotors 39 to 43 so that the control states calculated or determined in steps S5 to S9 are obtained (step S10). Then, in step S11, the process returns to step S2 after waiting for elapse of the control cycle time τ (for example, 0.5 seconds to 2.5 seconds).

Next, the control process for determining the suction port mode will be described with reference to FIG.
It will be described based on. Here, FIG. 7 is a flowchart showing a control process for determining the suction port mode. First, the suction port mode is determined from the characteristic diagram (map) of FIG. 8 stored in the ROM in advance (step S20). Subsequently, it is determined whether or not the suction port mode determined in step S20 is the outside air introduction mode (suction port mode determination means: step S21). When the determination result is NO, that is, when the suction port mode is determined to be the inside air circulation mode, the first suction switching door 6 is set to the solid line position in FIG. Set to the position indicated by the dashed line. That is, at this time, the first air passage 18 and the second air passage 19
Then, the suction port mode is determined so as to be controlled to the inside air circulation mode in which the inside air is introduced (step S22). Then, the process exits this subroutine.

If the result of the determination in step S21 is YES
In the case of, it is determined whether the outlet mode determined in step S6 of FIG. 6 is either the FOOT mode or the F / D mode. That is, it is determined whether or not the mode is the outlet mode for performing both heating of the vehicle interior and anti-fog of the front shield glass (outlet mode determining means: step S23). If the determination result is NO, the first suction port switching door 6 is set to the dashed line position in FIG. 4 and the second suction port switching door 7 is set to the solid line position. That is, at this time, the suction port mode is determined so that the outside air is introduced into the first air passage 18 and the second air passage 19 in the outside air introduction mode (step S24). Then, the process exits this subroutine.

If the result of the determination in step S23 is YES
In the case of, the air conditioning state (heating state) in the vehicle interior is MAXH
It is determined whether or not it is near OT. Specifically, it is determined whether or not the target door opening (SW) of the first and second air mix doors 3 and 4 determined in step S7 of FIG. 6 is 80 (%) or more. That is, the first and second air mix doors 3,
4 is controlled to be near the position (MAXHOT position) where most of the cool air from the evaporator 15 passes through the heater core 17 (maximum heating determining means: step S
25). If the result of this determination is NO, step S2
In the process of step 4, the suction port mode is determined so that the first air passage 18 and the second air passage 19 are both controlled to the outside air introduction mode in which outside air is introduced.

If the result of the determination in step S25 is YES
In this case, it means that the heating capacity is insufficient with respect to the target outlet temperature (TAO), and the first and second inlet switching doors 6 and 7 are set to the solid line positions in FIG. In other words, the suction port mode is determined so that the inside air is introduced into the first air passage 18 and the inside air is introduced into the second air passage 19 so as to be controlled to the inside / outside air two-layer mode (step S26). Then, the process exits this subroutine.

Next, control processing of frost control will be described with reference to FIG. Here, FIG. 9 is a flowchart showing the control processing of the frost control. First, it is determined whether or not the suction mode is controlled to the inside / outside air two-layer mode (step S30). If this determination is NO,
It is determined whether or not the suction port mode is controlled to the outside air introduction mode (step S31). If the result of this determination is NO, the suction port mode is controlled to the inside air circulation mode, so that the first post-evaporation temperature detected by the first post-evaporation temperature sensor 55 and the detection by the second post-evaporation temperature sensor 56 are detected. The temperature is equal to the second post-evaporation temperature. Therefore, for example, the first post-evaporation temperature TEin detected by the first post-evaporation temperature sensor 55 is determined as the post-evaporation temperature TE (step S32).

If the result of the determination in step S31 is YES
In the case of, since the suction port mode is controlled to the outside air introduction mode, the first post-evaporation temperature sensor 55 detects
The second post-evaporation temperature and the second post-evaporation temperature sensor 56
It matches the temperature after evaporation. Therefore, for example, the second post-evaporation temperature TEout detected by the second post-evaporation temperature sensor 56 is determined as the post-evaporation temperature TE (step S33).

If the result of the determination in step S30 is YES
In the case of, the first post-evaporation temperature sensor 55 detects the first
It is determined whether the post-evaporation temperature TEin is higher than or equal to the second post-evaporation temperature TEout detected by the second post-evaporation temperature sensor 56 (lower temperature side determination means: step S34). If this determination result is NO, that is, if the first post-evaporation temperature TEin
If the temperature is lower than the post-evaporation temperature TEout, the first post-evaporation temperature TEin is read as the post-evaporation temperature TE1 (step S35).

Subsequently, a correction value corrected by adding the influence of the second post-evaporation temperature TEout to the post-evaporation temperature TE1 read in step S35 is determined as the post-evaporation temperature (correction temperature) TE (post-evaporation temperature correction means: Step S36). Specifically, the post-evaporation temperature TE is calculated based on the following equation (3).

## EQU3 ## TE = TE1 + KEout × TEout + C1 Note that KEout is a gain and C1 is a correction constant.

If the result of the determination in step S34 is YES
In other words, if the second post-evaporation temperature TEout is lower than or equal to the first post-evaporation temperature TEin, the second post-evaporation temperature T
Eout is read as the post-evaporation temperature TE2 (step S37). Subsequently, a correction value corrected by adding the influence of the first post-evaporation temperature TEin to the post-evaporation temperature TE2 read in step S37 is determined as the post-evaporation temperature (correction temperature) TE (post-evaporation temperature correction means: step S38). . Specifically, the post-evaporation temperature TE is calculated based on the following equation (4).

## EQU4 ## TE = TE2 + KEin × TEin + C2 where KEin is a gain and C2 is a correction constant.

Subsequently, ON / OFF of the compressor 11 is determined using a characteristic diagram (map) stored in the ROM in advance (step S39). Specifically, step S
32, S33, S36, the post-evacuation temperature T determined in S38
When E is equal to or higher than the first predetermined temperature (4 ° C. in the present embodiment), the refrigeration cycle 10 is operated by controlling the energization of the electromagnetic clutch 16 so that the compressor 11 starts (ON). That is, the evaporator 15 is operated (air cooling action).
Let it. Steps S32, S33, S36, S3
When the post-evaporation temperature TE determined in step 8 is equal to or lower than the second predetermined temperature (3 ° C. in the present embodiment), the energization control of the electromagnetic clutch 16 is performed so that the operation of the compressor 11 is stopped (OFF), and the operation of the refrigeration cycle 10 is performed. To stop. That is, the air cooling operation of the evaporator 15 is stopped.

[Operation of the First Embodiment] Next, the operation of each air-conditioning means of the air-conditioning unit 1 when the inlet mode is the inside / outside air two-layer mode and the outlet mode is the FOOT mode or the F / D mode will be described. This will be briefly described with reference to FIGS.

When the air inlet mode is determined to be the outside air introduction mode, the air outlet mode is determined to be the FOOT mode or the F / D mode, and the air condition in the passenger compartment is near MAXHOT, the first and second air inlet switching doors 6 are provided. , 7 move to the solid line position in FIG. 4, the foot door 21 moves to the solid line position in FIG. 1, the defroster door 22 moves to the dashed-dotted line position, and the face door 23 moves to the solid line position. Is controlled as follows.

Therefore, the inside air existing in the passenger compartment is turned by the rotation of the first fan 31 of the blower 8 into the first inside air suction port 5.
a is sucked into the inside / outside air switching box 5 from the
Of the first scroll casing 3 through the first suction port 8a
It is sucked in 4. Then, the inside air enters the first air passage 18 of the air-conditioning duct 2 and the first air of the evaporator 15.
Pass through the cooling section. Then, after the inside air is cooled when passing through the first cooling section and becomes cool air, the temperature thereof is detected by the first post-evaporation temperature sensor 55, and the temperature is further detected by the heater core 17.
Pass through the first heating section. Then, the cold air is reheated when passing through the first heating unit to become hot air,
FOOT penetrates into the foot duct through the T opening 2a and
The air is blown out from the air outlet toward the foot of the occupant of the vehicle.
As a result, the interior of the vehicle is heated by the already warmed interior air, so that the heating performance is excellent.

On the other hand, the outside air existing outside the vehicle compartment is rotated by the rotation of the second fan 32 from the outside air suction port 5 c to the inside / outside air switching box 5.
And is further sucked into the second scroll casing part 35 through the second suction port 8b. Then, the outside air enters the second air passage 19 of the air conditioning duct 2 and passes through the second cooling unit of the evaporator 15. Then, after the outside air is cooled when passing through the second cooling unit and becomes cold air, the temperature is detected by the second post-evaporation temperature sensor 56,
Further, it passes through the second heating section of the heater core 17. Then, the cold air is reheated when passing through the second heating section to become hot air, and then enters the defroster duct from the DEF opening 2b and is directed from the DEF outlet toward the foot of the occupant of the vehicle. Is blown out. Thereby, low-humidity outside air blows out to the inner surface of the front shield glass, so that the front shield glass is excellent in anti-fog performance.

[Effects of the First Embodiment] In the present embodiment,
The first and second post-evaporation temperature sensors 55 and 56 are disposed in the first and second air passages 18 and 19, respectively, so that when the suction mode is controlled to the inside / outside air two-layer mode, 1st post-evacuation temperature TE immediately downstream of 1 cooling section
1 and the second post-evaporation temperature TE2 immediately downstream of the second cooling section of the evaporator 15, a corrected temperature obtained by adding a value taking into account the high-temperature side post-evaporation temperature to the low temperature side post-evaporation temperature TE. The frost control is performed based on the calculated post-evaporation temperature TE.

Therefore, in the control process of the frost control of the present embodiment, when the intake temperature of the inside air sucked into the first air passage 18 is lower than the suction temperature of the outside air sucked into the second air passage 19, By determining ON / OFF of the compressor 11 using the post-evaporation temperature TE associated with the first post-evaporation temperature TE1 which is the temperature on the inside air side, the first cooling unit of the evaporator 15 on the low temperature side is frosted. Since the operation of the evaporator 15 stops before,
The first cooling section of the evaporator 15 does not frost. Then, the second after-evacuation temperature TE is the temperature on the outside air side.
Since the correction temperature takes into account the post-evaporation temperature TE2, 10
The temperature after the second evaporation TE
Since the operation of the evaporator 15 is stopped when 2 is close to the second predetermined temperature, it is also possible to suppress a decrease in the dehumidifying performance of the second cooling unit of the evaporator 15, that is, the dehumidifying performance of the outside air.

When the intake temperature of the outside air drawn into the second air passage 19 is lower than the suction temperature of the inside air drawn into the first air passage 18, the second evaporator, which is the temperature on the outside air side, is used. By determining ON / OFF of the compressor 11 using the post-evaporation temperature TE related to the post-temperature TE2, the operation of the evaporator 15 is stopped before the second cooling unit of the low-temperature side evaporator 15 is frosted.
The second cooling part of the evaporator 15 does not frost. Then, the first temperature at which the post-evaporation temperature TE is the temperature on the inside air side is set.
Since it is a correction temperature in consideration of the post-evaporation temperature TE1, 10
Even after a low outside air temperature range of less than 100 ° C, the temperature TE after the first evaporation
Since the operation of the evaporator 15 is stopped when 1 is close to the second predetermined temperature, it is also possible to suppress a decrease in the dehumidifying performance of the first cooling unit of the evaporator 15, that is, the dehumidifying performance of the inside air.

As described above, in the air conditioning unit 1 of this embodiment, the post-evaporation temperature of only one of the first air passage (inside air passage) 18 and the second air passage (outside air passage) 19 is detected. Compared to the frost control, it is possible to perform frost control giving priority to the frost prevention effect, which is less susceptible to fluctuations in the intake air between summer when the outside air temperature is high and winter when the outside air temperature is low. Specifically, compared to an air conditioning unit provided with a post-evaporation temperature sensor only on the first air passage 18 side, clogging of the second cooling unit on the second air passage 19 side due to frost can be suppressed. Thus, a decrease in the amount of air blown from the DEF outlet toward the front shield glass can be suppressed, so that a decrease in the anti-fog performance of the front shield glass can be suppressed.

Further, as compared with an air conditioning unit provided with a post-evaporation temperature sensor only on the second air passage 19 side, it is possible to suppress a decrease in the dehumidifying performance of air blown out from the FOOT outlet toward the feet of the occupant. . As a result, an increase in the humidity of the inside air can be suppressed, so that the inner surfaces of the front shield glass, the side shield glass, and other shield glasses are less likely to be fogged.

Further, the first post-evaporation temperature TE1 immediately downstream of the first cooling portion of the evaporator 15 detected by the first post-evaporation temperature sensor 55 and the second cooling portion of the evaporator 15 detected by the second post-evaporation temperature sensor 56. By calculating the target door openings of the first and second air mix doors 3 and 4 using the second post-evaporation temperature TE2 immediately downstream of
The temperature of the air blown out from the DEF air outlet toward the front shield glass and the temperature of the air blown out from the FOOT air outlet toward the feet of the occupant can be appropriately adjusted.

[Structure of Second Embodiment] FIG. 10 shows a second embodiment of the present invention, and FIG. 10 is a flowchart showing control processing of frost control.

In the present embodiment, while the first embodiment performs frost control giving priority to the frost prevention effect,
Frost control is performed to give priority to the effect of preventing the dehumidification performance from decreasing. Specifically, the following control processing is performed. Steps S40 to S43 and S49 are performed in step S30 of FIG.
Since the control processing is the same as that of S33 and S39, the description is omitted.

If the suction port mode is controlled to the inside / outside air two-layer mode (the determination result in step S40 is YES), the first post-evaporation temperature TEin detected by the first post-evaporation temperature sensor 55 is set to the second It is determined whether the temperature is higher than or equal to the second post-evaporation temperature TEout detected by the post-evaporation temperature sensor 56 (high-temperature side determination means: step S44). If this determination result is YES, that is, if the first post-evaporation temperature TEin is higher than or equal to the second post-evaporation temperature TEout, the first post-evaporation temperature TEin is read as the post-evaporation temperature TE1 (step S45).

Subsequently, a correction value corrected by adding the influence of the second post-evaporation temperature TEout to the post-evaporation temperature TE1 read in step S45 is determined as the post-evaporation temperature (correction temperature) TE (post-evaporation temperature correction means: Step S46). Specifically, the post-evaporation temperature TE is calculated based on the following equation (5). Thereafter, the control processing of step S49 is performed.

## EQU5 ## TE = TE1−KEout × TEout + C1 where KEout is a gain and C1 is a correction constant.

If the result of the determination in step S44 is NO, that is, if the second post-evaporation temperature TEout is higher than the first post-evaporation temperature TEin, the second post-evaporation temperature TEout
out is read as the post-evaporation temperature TE2 (step S
47). Subsequently, a correction value corrected by adding the influence of the first post-evaporation temperature TEin to the post-evaporation temperature TE2 read in step S47 is determined as the post-evaporation temperature (correction temperature) TE (post-evaporation temperature correction means: step S48). . Specifically, the post-evaporation temperature TE is calculated based on the following equation (6). Thereafter, the control processing of step S49 is performed.

## EQU6 ## TE = TE2−KEin × TEin + C2 where KEin is a gain and C2 is a correction constant.

[Effect of Second Embodiment] In the present embodiment,
The first and second post-evaporation temperature sensors 55 and 56 are disposed in the first and second air passages 18 and 19, respectively, so that when the suction mode is controlled to the inside / outside air two-layer mode, 1st post-evacuation temperature TE immediately downstream of 1 cooling section
1 and the second post-evaporation temperature TE2 immediately downstream of the second cooling section of the evaporator 15, the post-evaporation temperature TE is a correction temperature obtained by adding a value in consideration of the low-temperature side post-evaporation temperature to the high-temperature side post-evaporation temperature. The frost control is performed based on the calculated post-evaporation temperature TE.

Therefore, in the control processing of the frost control of the present embodiment, when the suction temperature of the inside air sucked into the first air passage 18 is higher than the suction temperature of the outside air sucked into the second air passage 19, By determining ON / OFF of the compressor 11 using the post-evaporation temperature TE related to the first post-evaporation temperature TE1 which is the temperature on the inside air side, even in a low outside air temperature region of 10 ° C. or less, After one evaporator temperature TE1 is close to the second predetermined temperature, evaporator 15
Is stopped, so that the dehumidifying performance of the first cooling portion of the evaporator 15, that is, the dehumidifying performance of the inside air can be prevented from being lowered. And the temperature TE after evaporation
Is a correction temperature in consideration of the second post-evaporation temperature TE2, which is the temperature on the outside air, so that the frost of the second cooling unit of the evaporator 15 on the low temperature side can be suppressed even in a low outside air temperature region of 10 ° C. or less. Can also.

When the suction temperature of the outside air sucked into the second air passage 19 is higher than the suction temperature of the inside air sucked into the first air passage 18, the second air which is the temperature on the outside air side is used. By determining ON / OFF of the compressor 11 using the post-evaporation temperature TE, which is a correction temperature in consideration of the first post-evaporation temperature TE1, as the post-temperature TE2, 10 ° C.
Even in the following low outside air temperature range, the first post-evaporation temperature TE1
Is stopped at a value close to the second predetermined temperature, the operation of the evaporator 15 is stopped before the second cooling unit of the evaporator 15 on the low temperature side is frosted. The cooling section does not frost.

[Third Embodiment] FIG. 11 shows a third embodiment of the present invention, and FIG. 11 is a flowchart showing control processing of frost control.

In the present embodiment, the following control processing is performed.
Steps S50 to S53 and S59 are the same control processes as steps S30 to S33 and S39 in FIG. If the suction port mode is controlled to the inside / outside air two-layer mode (the determination result in step S50 is YES), the first post-evaporation temperature TEin detected by the first post-evaporation temperature sensor 55 becomes the second post-evaporation temperature. It is determined whether the temperature is higher than or equal to the second post-evaporation temperature TEout detected by the sensor 56 (high / low temperature side determining means: step S54). If this determination is YES, that is, if the first post-evaporation temperature TEin
When the temperature is equal to or higher than the post-evaporation temperature TEout, the first post-evaporation temperature TEin is set to the high-temperature side post-evaporation temperature TEH, and the second
The post-evaporation temperature TEout is read as the low-temperature-side post-evaporation temperature TEL (step S55).

If the determination result in step S54 is NO, that is, if the second post-evaporation temperature TEout is higher than the first post-evaporation temperature TEin, the second post-evaporation temperature TEout is set to the higher temperature side. The post-evaporation temperature TEH is read, and the first post-evaporation temperature TEin is read as the low-temperature post-evaporation temperature TEL (step S56).

Subsequently, the first data stored in the ROM in advance
The predetermined temperature and the second predetermined temperature are read. Specifically, as the first predetermined temperature, a first set value TEH0 on the high temperature side (for example, 11 ° C.) and a first set value TEL0 on the low temperature side (for example, 4 ° C.).
° C), and the second set value TEH0 (for example, 10 ° C) on the high temperature side and the second set value TEL0 (for example, 3 ° C) on the low temperature side are read as the second predetermined temperatures (step S5).
7).

Characteristic diagram (map) stored in ROM in advance
Is used to determine ON / OFF of the compressor 11 (step S58). Specifically, the post-evaporation temperature TEH on the high temperature side is set to the first set value (for example, 11 ° C.) TEH0 on the high temperature side.
At this time, or when the low-temperature side post-evaporation temperature TEL is equal to or higher than the low-temperature side first set value (for example, 4 ° C.) TEL0, the electromagnetic clutch 16 is energized so that the compressor 11 starts (ON) and the refrigeration cycle is performed. Activate 10 That is, the evaporator 15 is operated (air cooling action).
Let it.

When the post-evaporation temperature TEH on the high temperature side is equal to or lower than the second set value (for example, 10 ° C.) TEH0, or the post-evaporation temperature TEL on the low temperature side is set to the second set value (for example, 3 ° C.) T
When the pressure is equal to or less than EL0, the operation of the refrigeration cycle 10 is stopped by controlling the energization of the electromagnetic clutch 16 so that the operation of the compressor 11 is stopped (OFF). That is, the air cooling operation of the evaporator 15 is stopped.

In the present embodiment, by performing the above control processing at the time of the frost control, the air conditioning unit in which the post-evaporation temperature is provided only in the air passage having the high post-evaporation temperature is provided.
The air-conditioning unit 1 according to the present embodiment can avoid the possibility of the frost of the evaporator 15 in the air passage having the low temperature after the evaporation. In contrast to the air conditioning unit in which the post-evaporation temperature is provided only in the air passage having a low post-evaporation temperature, the air-conditioning unit 1 of the present embodiment has an air passage having a high post-evaporation temperature even in a low outside air temperature region. A decrease in the dehumidifying performance of the air flowing through the inside can be suppressed.

[Fourth Embodiment] FIG. 12 shows a fourth embodiment of the present invention, and FIG. 12 is a flowchart showing a control process for determining an air mix door opening degree.

The following control processing is performed for the control processing for determining the degree of opening of the air mix door in step S8 in FIG. 6 of the first embodiment. In the present embodiment, the target door opening (SW1) of the first air mix door 3 is calculated based on the following equation (7) stored in the ROM in advance (step S60).

(7) SW1 = ｛(TAO-TE1) / (TW-TE
1)｝ × 100 (%) Note that TE1 was detected by the first post-evaporation temperature sensor 55,
The first post-evaporation temperature (actually measured value), which is the air temperature in the first air passage 18 immediately downstream of the evaporator 15, and TW are the cooling water temperature detected by the water temperature sensor 54.

Subsequently, the target door opening (SW2) of the second air mix door 4 is calculated based on the following equation (8) stored in the ROM in advance (step S61).

## EQU8 ## SW2 = ｛(TAO-TE2) / (TW-TE
2)｝ × 100 (%) Note that TE2 was detected by the second post-evaporation temperature sensor 56,
The first post-evaporation temperature (actually measured value), which is the air temperature in the second air passage 19 immediately downstream of the evaporator 15, and TW are the cooling water temperature detected by the water temperature sensor 54.

In this embodiment, the first post-evaporation temperature sensor 5
At 5, the first cooling unit immediately downstream of the first cooling unit of the evaporator 15
The temperature after the evaporation TE1 is detected, and the second temperature after the evaporation
Detects the second post-evaporation temperature TE2 immediately downstream of the second cooling section of the evaporator 15, so that the target door opening of the first and second air mix doors 3, 4 is performed using the two post-evaporation temperatures. By calculating the respective degrees, the temperature of the air blown out from the DEF outlet toward the front shield glass and the temperature of the air blown out from the FOOT outlet toward the feet of the occupant are adjusted to an appropriate vertical temperature difference (for example, 10 ° C
-15 ° C). Here, in general, the upper outlet (DEF outlet or FACE outlet) depends on the shape of the air conditioning case 2 and the degree of opening of each door 21 to 23.
Outlet temperature (FOO) lower than the temperature of the air
T outlet), the temperature of the air blown out is, for example, 10 ° C.
The temperature is raised to about 15 ° C.

When the inlet mode is the inside / outside air two-layer mode, the target outlet temperature (TAO) is also equal to the target outlet temperature (TAO1) of the air blown from the FOOT outlet through the first air passage 18. (2) Target outlet temperature of air blown out of DEF outlet through air passage 19 (TAO2)
And a suitable vertical temperature difference (for example, 10 ° C. to 15 ° C.) between the temperature of the air blown out from the DEF outlet toward the front shield glass and the temperature of the air blown out from the FOOT outlet toward the feet of the occupant. ° C), the target door openings of the first and second air mix doors 3 and 4 may be controlled.

[Other Embodiments] In this embodiment, the evaporator 15 of the refrigeration cycle 10 is used as the cooling heat exchanger, and the heater core 17 is used as the heating heat exchanger. A heat exchanger incorporating an air cooling component such as an element may be used, or a heat exchanger incorporating an air heating component such as an electric heater may be used as a heat exchanger for heating.

In this embodiment, the first and second post-evaporation temperature sensors 55 and 56 for detecting the air temperature immediately after passing through the evaporator 15 are used as the first and second cooling degree detecting means. As the second cooling degree detecting means, first and second temperature sensors for detecting the fin temperature of the evaporator 15 and first and second switches may be used. First,
As the second cooling degree detecting means, first and second refrigerant pressure detecting means (refrigerant pressure sensor, refrigerant pressure switch) for detecting the low pressure of the refrigeration cycle 10 may be used.

In this embodiment, at the time of automatic control, the suction port mode is determined to be the outside air introduction mode, and the air outlet mode is set to F
Determined to be OOT mode or F / D mode, MAXH
When the OTT was determined, the first and second inlet switching doors 6 and 7 were moved to the inside / outside air two-layer mode. However, during manual control, the outside air introduction switch was turned on, and the foot switch or foot differential was turned on. When the switch is turned on and the heating state in the vehicle compartment is set to the maximum heating state (near MAXHOT) by an operation lever such as a temperature setting lever, the first and second suction port switching doors 6 and 7 are moved between the inside and outside air two layers. It may be moved so as to be in the mode.

In the present embodiment, the control for determining the suction port mode to the inside / outside air two-layer mode is performed near MAXHOT, that is, when the target door opening (SW) is determined to be 80% or more. When the target door opening (SW) is determined to be 100% or more, control may be performed to determine the suction mode to the inside / outside air two-layer mode. In the control process for determining the suction port mode, the target outlet temperature (TA
Control processing for determining one of the inside air circulation mode, the outside air introduction mode, and the inside / outside air two-layer mode based on the value of O) may be performed. Further, a suction port changeover switch for forcibly fixing the suction port mode to the inside / outside air two-layer mode may be provided.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing an overall configuration of a ventilation system of a vehicle air conditioner (first embodiment).

FIG. 2 is a sectional view taken along line AA of FIG. 1 (first embodiment).

FIG. 3 is a sectional view taken along line BB of FIG. 1 (first embodiment).

FIG. 4 is a schematic perspective view seen from the direction of arrow C in FIG. 1 (first embodiment).

FIG. 5 is a block diagram showing a control system of the vehicle air conditioner (first embodiment).

FIG. 6 is a flowchart showing a control process by the microcomputer (first embodiment).

FIG. 7 is a flowchart showing a control process for determining a suction port mode in FIG. 6 (first embodiment).

FIG. 8 is a characteristic diagram showing a relationship between an inlet mode and a target outlet temperature (first embodiment).

FIG. 9 is a flowchart showing a control process of frost control in FIG. 6 (first embodiment).

FIG. 10 is a flowchart showing a control process of frost control in FIG. 6 (second embodiment).

FIG. 11 is a flowchart showing a control process of frost control in FIG. 6 (third embodiment).

FIG. 12 is a flowchart showing a control process of determining an air mix door opening in FIG. 6 (fourth embodiment).

FIG. 13 shows experimental data when a temperature detecting means is provided on the first air passage side.

FIG. 14 shows experimental data when a temperature detecting means is provided on the second air passage side.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Air-conditioning unit 2 Air-conditioning case 3 1st air mix door 4 2nd air mix door 5 Inside / outside air switching box 6 1st inlet switching door 7 2nd inlet switching door 8 Blower (blowing means) 9 ECU (air conditioning control means) Reference Signs List 10 Refrigeration cycle 15 Evaporator (cooling heat exchanger) 17 Heater core 18 First air passage 19 Second air passage 20 Partition plate (partition member) 55 First post-evaporation temperature sensor (first cooling degree detecting means,
(First temperature detecting means) 56 Second post-evaporation temperature sensor (second cooling degree detecting means,
First temperature detecting means) 2a FOOT opening 2b DEF opening 2c FACE opening 5a First inside air suction port (first suction port) 5b Second inside air suction port 5c Outside air suction port (second suction port)

Claims (5)

[Claims] (A) an air conditioning case for sending air into a vehicle interior; (b) air blowing means for generating an air flow toward the vehicle interior in the air conditioning case; and (c) air in the air conditioning case. A partition member that is provided along the flow direction of the air-conditioning case and partitions the interior of the air-conditioning case into a first air passage through which vehicle interior air mainly flows and a second air passage mainly through which vehicle exterior air flows. A) a cooling heat exchanger that cools air flowing through the first air passage and the second air passage; and (e) a first heat exchanger provided in the first air passage and provided by the cooling heat exchanger. First cooling degree detecting means for detecting the degree of air cooling on the air passage side; and (f) detecting the degree of air cooling on the second air passage side provided by the cooling heat exchanger in the second air passage. (G) second cooling degree detecting means for performing The air cooling degree on the first air passage side detected by the first cooling degree detection means or the air cooling degree on the second air passage side detected by the second cooling degree detection means is determined by the air cooling degree. An air conditioner for a vehicle, comprising: air conditioning control means for controlling an operation state of the cooling heat exchanger in response. 2. The vehicle air conditioner according to claim 1, wherein the first air passage directs vehicle interior air sucked from a first suction port to a foot portion of a vehicle occupant from a first air outlet. The second air passage is a ventilation passage through which the outside air of the vehicle sucked in from the second suction port is blown out from the second air outlet toward the window glass. Vehicle air conditioner. 3. The air conditioner for a vehicle according to claim 1, wherein the first cooling degree detecting means is configured to detect the air on the first air passage side immediately after passing through the cooling heat exchanger. A first temperature detecting means for detecting a temperature, wherein the second cooling degree detecting means is a second temperature detecting means for detecting an air temperature on the second air passage side immediately after passing through the cooling heat exchanger. An air conditioner for a vehicle, comprising: 4. The air conditioner for a vehicle according to claim 3, wherein the air conditioning control means detects the air temperature on the first air passage side detected by the first temperature detection means or the air temperature on the side of the first air passage detected by the second temperature detection means. Operating the cooling heat exchanger when one of the air temperatures on the second air passage side is equal to or higher than a first predetermined temperature, and the one air temperature is lower than the first predetermined temperature. An air conditioner for a vehicle, wherein the operation of the cooling heat exchanger is stopped when the temperature is lower than a low second predetermined temperature. 5. The air conditioner for a vehicle according to claim 4, wherein the air conditioning control means detects the air temperature on the first air passage side detected by the first temperature detection means or the air temperature on the side of the first air passage detected by the second temperature detection means. Operating the cooling heat exchanger when the corrected temperature obtained by adding the effect of the other air temperature to the air temperature of one of the air temperatures on the second air passage side is equal to or higher than the first predetermined temperature, An air conditioner for a vehicle, wherein the operation of the cooling heat exchanger is stopped when the corrected temperature is equal to or lower than the second predetermined temperature.