JPH1191333A - Air conditioner for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the impairing of the dehumidifying performance and the frost formation of an evaporator in a low atmospheric temperature range and to prevent the generation of the white fog in a high atmospheric temperature range. SOLUTION: This device is provided with a partitioning plate 20 for partitioning an inside of an air conditioner case into a first air duct 18 for sucking the inside air, and a second air duct 19 for sucking an outside air, and has an inside and outside air two layered mode, an inside air circulating mode and an outside air introducing mode as the inlet port mode. In a case when it is judged that a compressor 11 of a refrigerating cycle is ON, the inlet port mode is switched from the inside and outside air two layered mode to the outside air introducing mode. Whereby the outside air sucked from the outside air inlet port, is blown into a cabin through the both of the first and second air passages 18, 19, so that the temperature difference is not generated on the temperature of the air passed through the first and second air passages 18, 19.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention comprises a partition member for partitioning the interior of an air-conditioning case into a first air passage through which vehicle interior air or outside vehicle air flows and a second air passage mainly through which vehicle exterior air flows. And a vehicle air conditioner.

[0002]

2. Description of the Related Art As a prior art of such an air conditioner for a vehicle, there is a technique disclosed in Japanese Patent Application Laid-Open No. 7-47831. In this prior art configuration, an inside air inlet and an outside air inlet are formed at one end of an air conditioning case, and a foot outlet, a defroster outlet, and a face outlet are formed at the other end. And the internal space of the air conditioning case,
A first air passage through which vehicle interior air mainly flows and a second air passage mainly through outside vehicle air are defined by a partition plate, and a blower, an evaporator and a heater core are provided in the air conditioning case. . Furthermore, the 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.

[0003]

However, in the above prior art, consideration has been given to concerns about the behavior of the evaporator in the inside / outside air two-layer mode when the outside air temperature is equal to or lower than a predetermined temperature (for example, 0 ° C.). Absent. Specifically, in the case where the post-evaporation temperature sensor is provided on the side of the first air passage through which the vehicle interior air flows, data shown in FIG. 9 is obtained,
The data shown in FIG. 10 was obtained when the post-evaporation temperature sensor was provided on the side of the second air passage through which the outside air flows mainly.

[0004] From these data, it can be understood that, when the post-evaporation temperature sensor is provided on the second air passage (outside air layer) side, as shown in FIG. Before the evaporator temperature on the side of the passage (inner air layer) decreases to the limit frost temperature (for example, 3 ° C.), the operation of the evaporator is stopped. descend. 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 first air passage (inner air layer) side, as shown in FIG. 10, dehumidifying performance can be ensured in each of the first and second air passages. When the outside air temperature is in the low outside air temperature range of 10 ° C. or lower, the post-evaporation temperature on the second air passage side 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 (outside air layer) 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. .

Further, when the outside air temperature is a predetermined value (for example, 35
In the case of a high outside air temperature range of not less than (° C.), the face mode is selected as the outlet mode. In this case, after mixing the vehicle interior air that has passed through the first air passage and the vehicle exterior air that has passed through the second air passage downstream of the evaporator, the air is blown out from the face outlet.
However, downstream of the evaporator, low-temperature (for example, 25 ° C.) vehicle interior air in the first air passage (inner air layer) and high-temperature (for example, 35 ° C.) vehicle outside air in the second air passage (outer air layer) Is mixed, there arises a problem that white fog is generated due to a difference in inside and outside air temperature.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to prevent a decrease in dehumidifying performance or a frost on a cooling heat exchanger in a low outside air temperature range,
Another object of the present invention is to provide an air conditioner for a vehicle that can solve the problems at the time of operating a cooling heat exchanger by preventing the generation of white fog in a high outside air temperature range.

[0008]

According to the first aspect of the present invention, when the cooling heat exchanger is operating, the mode is switched to the outside air introduction mode by the suction port mode switching means. Thereby, the vehicle outside air sucked from the outside air suction port is blown into the vehicle room through both the first air passage and the second air passage. As a result, the temperature of the air sucked into the cooling heat exchanger has no temperature difference between the first air passage side and the second air passage side. Frost of the heat exchanger for use can be prevented, and generation of white fog in a high outside air temperature range can be prevented. As a result, the problem at the time of operating the cooling heat exchanger can be solved.

According to the second or third aspect of the present invention, when the operation time of the refrigerant compressor is equal to or more than a predetermined value within a predetermined time, or when the discharge capacity of the refrigerant compressor is equal to or more than a predetermined value, the outside air By switching to the introduction mode, the vehicle outside air sucked from the outside air suction port is supplied to the first air passage and the second air passage.
The air is blown into the passenger compartment through both of the air passages. Thereby, the temperature of the air sucked into the cooling heat exchanger is
Since no temperature difference occurs between the first air passage side and the second air passage side, the same effect as the first aspect of the invention can be achieved.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION

[Configuration of First Embodiment] FIGS. 1 to 7 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 air conditioner for a vehicle according to 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 controller (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 FIG. 2 and FIG. 3, the first and second heater cores 17 allow the cool air to bypass the heater core 17.
A cooling heat exchanger is provided so as to form the bypass passages 18a and 19a, in which cooling water for cooling the engine flows, and the cooling water is used as a heat source for heating to reheat cold air. Further, the heater core 17 penetrates a partition plate 20 to be described later and is inside the air conditioning case 2.
A first heating unit for heating air flowing in a first air passage 18 described later and an air flowing in a second air passage 19 described later are disposed so as to partially block the width direction or the height direction of the air. And a second heating unit for heating the second heating unit.

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 outside air (hereinafter referred to as outside air) sucked from an outside air suction port 5c, which will be described later, through a defroster (DEF) opening 2b and a face (FACE) opening 2c, and a defroster outlet and a center. 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 component 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 center door duct. An air outlet switching door that opens and closes 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 servomotor 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 configurations 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. A first inside air suction port 5a is formed in the inside / outside air switching box 5 corresponding to the first suction port 8a of the blower 8, and the second suction port 8a of the blower 8 is formed.
b corresponding to the second inside air suction port 5b and the outside air suction port 5c.
Are formed.

The first suction port switching door 6 corresponds to the suction port mode switching means of the present invention, and includes the first inside air suction port 5a.
Is a plate-like door that opens and closes. The second suction port switching door 7 corresponds to the suction port mode switching means of the present invention, and is a plate-like door that opens and closes the second inside air suction port 5b and the outside air suction port 5c. Servo motors 42 and 43 (see FIG. 5) as driving means are connected to the first and second suction port switching doors 6 and 7, respectively. It is rotated between a solid line position and an alternate long and short dash line position.

The inside / outside air switching box 5 is provided with a communication passage 30 for communicating the second inside air suction port 5b or the outside air suction port 5c with the first suction port 8a. Then, the first suction port switching door 6 completely closes the communication passage 30 when the first inside air suction port 5a is fully opened (the position indicated by the solid line in FIG. 4), and completely closes the first inside air suction port 5a (see FIG. 4). 4 at the dot-dash line)
Fully open 0.

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. A switch signal from each switch on an operation panel 37 provided on the front surface of the vehicle compartment is input to an air conditioner 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, each switch on the operation panel 37 is
For example, the air conditioner switch 50 for instructing the start and stop of the refrigeration cycle 10, the temperature setting switch for the occupant to set the vehicle interior set temperature, the suction port changeover switch for changing the suction mode, and the changeover for the air outlet mode. Air outlet switch, first and second fans 3
An air volume changeover switch for switching the air volume of 1, 32;
It is an auto switch for instructing automatic control of each air conditioner.

Note 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 is a switch, a foot differential switch for fixing to a foot differential (F / D) mode, and a differential switch for fixing to a defroster (DEF) mode.

The air conditioner ECU 9 has an inside air temperature sensor 51 for detecting the air temperature inside the vehicle (inside air temperature) and an outside air temperature sensor 5 for detecting the air temperature outside the vehicle room (outside air temperature).
2. Solar radiation sensor 5 for detecting the amount of solar radiation applied to the vehicle interior
3. The sensor signals from the water temperature sensor 54 for detecting the temperature of the cooling water flowing into the heater core 17 and the post-evaporation temperature sensor 55 for detecting the degree of air cooling in the first air passage 18 immediately after the evaporator 15 are input. Among them, the post-evaporation temperature sensor 55 is a temperature detecting means such as a thermistor for detecting the air temperature in the first air passage 18 immediately after passing through the evaporator 15.

A well-known microcomputer including a CPU, a ROM, a RAM, and the like (not shown) is provided inside the air conditioner ECU 9.
Is converted from an A / D signal by an input circuit (not shown) in the air conditioner ECU 9 and then input to the microcomputer. Air conditioner E
The CU 9 is supplied with power from a battery (not shown) when an ignition switch (not shown) of the engine of the automobile is turned on.

Next, control processing 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 air conditioner ECU 9, the routine of FIG. 6 is started, and each initialization and initialization are performed (step S1). Subsequently, the set temperature set by the temperature setting switch is read (Step S).
2). Subsequently, an inside air temperature sensor 51, an outside air temperature sensor 52,
A / D converted signals of the sensor signals from the solar radiation sensor 53, the water temperature sensor 54, and the post-evaporation temperature sensor 55 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 (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 blowout 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 this embodiment, when the defroster switch provided on the operation panel 37 is operated, the foot door 21 and the defroster door 22 are moved to the position indicated by the dashed line in FIG.
The DEF mode in which the face door 23 is set to the solid line position and the conditioned air 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, the target door opening (SW) of the first and second air mixing doors 3, 4 is calculated based on the following equation (2) stored in the ROM in advance (step S7).

## EQU2 ## SW = {(TAO-TE) / (TW-TE)}
× 100 (%) Note that TE is the post-evaporation temperature detected by the post-evaporation temperature sensor 55 and TW is the cooling water temperature detected by the water temperature sensor 54.

On the other hand, 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.
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 and 7 are determined (step S8). Subsequently, control signals are output to the blower motor 33 and the servo motors 39 to 43 so that the control states calculated or determined in steps S5 to S9 are obtained (step S9). And
In step S10, the control waits for the control cycle time τ (for example, 0.5 to 2.5 seconds), and then proceeds to step S2.
Return to the processing of.

Next, the control process for determining the suction port mode is shown in 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 inside / outside air two-layer mode (suction port mode determination means: step S21).

If the decision result in the step S21 is NO, the first suction port switching door 6 is moved to the position indicated by the solid line in FIG.
The suction port switching door 7 is set at the position indicated by the dashed line. That is,
At this time, the first air passage 18 and the second air passage 1
In S9, the suction port mode is determined so as to be controlled to the inside air circulation mode in which inside air is introduced (step S22).
Thereafter, the process exits the subroutine of FIG.

If the result of the determination in step S21 is YES
In this case, it is determined whether or not the outlet mode determined in step S6 in FIG. 6 is the DEF mode (outlet mode determining means: step S23). This determination result is Y
In the case of ES, the first suction port switching door 6 is set to the position indicated by the dashed line 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 both the first air passage 18 and the second air passage 19 in the outside air introduction mode (step S).
24). Thereafter, the process exits the subroutine of FIG.

If the result of the determination in step S23 is NO, the electromagnetic clutch 16 of the compressor 11 is turned on.
It is determined whether or not it has been performed. Specifically, when the ON time of the electromagnetic clutch 16 is t and the predetermined value is t0 (for example, 10 seconds), t ≧ within a predetermined time (for example, 1 minute).
At time t0, it is determined that the compressor 11 is ON (step S25). If the result of this determination is YES, the process moves to step S24, where the first air passage 18 and the second
The suction port mode is determined so that the outside air is introduced into the air passage 19 in the outside air introduction mode.

If the determination result in step S25 is NO, 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, 7 are provided. Is set to the position indicated by the solid line in FIG. That is, the first
The suction port mode is determined so that the inside air is introduced into the air passage 18 and the inside and outside air two-layer mode in which outside air is introduced into the second air passage 19 is controlled (step S26). Thereafter, the process exits the subroutine of FIG.

[Operation of First Embodiment] Next, the operation of each air-conditioning means of the air-conditioning unit 1 of this embodiment will be described with reference to FIGS.
This will be briefly described based on the above.

When the suction port mode is determined to be the inside / outside air two-layer mode and the outlet mode is determined to be any of the FACE mode, B / L mode, FOOT mode or F / D mode, the compressor 11 During the ON state, that is, when it is determined that the evaporator 15 of the refrigeration cycle 10 is operating, the first suction port switching door 6 moves to the dashed line position in FIG. After moving to the solid line position, the suction port mode is switched to the outside air introduction mode.

Therefore, the outside air sucked into the inside / outside air switching box 5 from the outside air suction port 5c by the rotation of the first fan 31 passes through the first suction port 8a, is sucked into the first scroll casing portion 34, and the first air flows into the first scroll casing 34. It enters the air passage 18. The outside air that has entered the first air passage 18 is cooled when passing through the first cooling unit of the evaporator 15 to become cool air, and further passes through the first heating unit of the heater core 17.

On the other hand, the outside air sucked into the inside / outside air switching box 5 from the outside air suction port 5c by the rotation of the second fan 32 passes through the communication path 30, passes through the second suction port 8b, and enters the second scroll casing portion 35. And enters the second air passage 19. The outside air that has entered the second air passage 19 is cooled when passing through the second cooling unit of the evaporator 15 to become cool air, and then the second air of the heater core 17 is cooled.
Pass through the heating section.

Here, when the outlet mode is the FACE mode, the foot door 21 moves to the dashed line position, the defroster door 22 moves to the solid line position, and the face door 23 moves to the dashed line position in FIG. After passing through the communication hole 20a and mixing with the air passing through the second air passage 19, the air is blown out from the FACE outlet through the FACE opening 2c toward the occupant's head and chest in the passenger compartment. Further, when the outlet mode is the FACE mode, since the amount of air heating in the first and second heating portions of the heater core 17 is small, the air is blown out from the FACE outlet through the first and second air passages 18 and 19. The vehicle interior is cooled by the cold air.

On the other hand, when the outlet mode is the B / L mode, the first and second air passages 18 are set by setting the foot door 21 and the defroster door 22 to the solid line position in FIG. , 19 is blown out from the FACE outlet and the FOOT outlet toward the occupant's head and chest and feet in the passenger compartment. Also, when the outlet mode is the FOOT mode, by setting the foot door 21 and the face door 23 to the solid line position in FIG. 1 and the defroster door 22 to the position where the DEF opening 2b is slightly opened, about 80% of the conditioned air is reduced. The air is blown out from the FOOT outlet toward the feet of the occupants in the passenger compartment, and about 20% of the conditioned air is blown out from the DEF outlet toward the inner surface of the front shield glass. Furthermore, the outlet mode is F / D
In the mode, the foot door 21 is set to the solid line position in FIG. 1, the defroster door 22 is set to the dash-dot line position, and the face door 23 is set to the solid line position. The air-conditioning wind directed toward the inner surface of the front shield glass is blown out by the same amount.

[Effects of the First Embodiment] The air conditioner for a vehicle according to the present embodiment operates when the compressor 11 is turned on, that is, when it is determined that the evaporator 15 of the refrigeration cycle 10 is operating. The mouth mode can be switched from the inside / outside air two-layer mode to the outside air introduction mode. Thereby, the outside air sucked from the outside air suction port 5c is blown into the vehicle interior through both the first and second air passages 18 and 19. Therefore, the temperature of the air sucked into the evaporator 15 does not differ between the first air passage 18 side and the second air passage 19 side, and the post-evaporation temperature sensor 55 is connected to the first and second air passages 18 and 19. No matter which of the two is installed, it is possible to prevent the deterioration of the dehumidifying performance in the low outside air temperature range or the formation of frost on the evaporator 15, and to prevent the generation of white fog in the high outside air temperature region.

[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, when the evaporator 15 is operating, the suction mode is switched from the inside / outside air two-layer mode to the outside air introduction mode. However, when the evaporator 15 is operating, the suction mode is set to the inside air circulation mode. The mode may be switched to the outside air introduction mode.

In the present embodiment, the first air passage (inner air space)
Although the post-evaporation temperature sensor 55 is installed on the 18 side, a post-evaporation temperature sensor may be installed on the second air passage (outside air layer) 19 side. Further, a post-evaporation temperature sensor may be installed in each of the first and second air passages 18 and 19.

[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.

FIG. 9 shows experimental data when a temperature detecting means is provided on the first air passage side.

FIG. 10 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 mixing door 4 2nd air mixing door 5 Inside / outside air switching box 6 1st suction-port switching door (suction-mode switching means) 7 2nd suction-switching door (suction-mode switching means) 8) blower (blower means) 9 air conditioner ECU (air conditioning control means) 10 refrigeration cycle 11 compressor (refrigerant compressor) 15 evaporator (cooling heat exchanger) 16 electromagnetic clutch 18 first air passage 19 second air passage 20 partition plate (Partition member) 55 Post-evaporation temperature sensor 2a FOOT opening 2b DEF opening 2c FACE opening 5a First inside air suction port 5b Second inside air suction port 5c Outside air suction port

Claims (3)

[Claims] (A) an outside air suction port for sucking air outside the vehicle compartment;
And an air-conditioning case provided with an inside air suction port for sucking air in the passenger compartment on the upstream side in the direction of air flow; (b) air blowing means for generating an airflow toward the passenger compartment in the air-conditioning case; The air conditioning case is provided along a flow direction of air in the case, and the inside of the air conditioning case is divided into a first air passage through which either the vehicle interior air or the vehicle exterior air flows and a second air passage through which mainly the vehicle exterior air flows. (D) two layers of inside and outside air that sucks vehicle interior air into the first air passage from the inside air suction port and sucks vehicle outside air into the second air passage from the outside air suction port A suction port mode switching means for switching between a mode and an outside air introduction mode for sucking outside air into the first air passage and the second air passage from the outside air suction port, and (e) the first air passage. A cooling heat exchanger for cooling air flowing in the passage and in the second air passage; and (f) when the cooling heat exchanger is operated, the suction port mode switching means switches to the outside air introduction mode. An air conditioner for a vehicle, comprising: an air conditioning control unit for controlling the air conditioning. 2. The air conditioner for a vehicle according to claim 1, wherein the cooling heat exchanger is a refrigerant evaporator of a refrigeration cycle, and the refrigeration cycle compresses and discharges the refrigerant. Wherein the air conditioning control means controls the suction port mode switching means to switch to the outside air introduction mode when the operation time of the refrigerant compressor is equal to or more than a predetermined value within a predetermined time. Air conditioner for vehicles. 3. The air conditioner for a vehicle according to claim 1, wherein the cooling heat exchanger is a refrigerant evaporator of a refrigeration cycle, and the refrigeration cycle compresses and discharges the refrigerant. Wherein the air conditioning control means controls the suction port mode switching means so as to switch to the outside air introduction mode when the discharge capacity of the refrigerant compressor is equal to or greater than a predetermined value. apparatus.