JPH08318725A - Air conditioner for vehicle - Google Patents

Abstract

PURPOSE: To improve air conditioning propert,y in a bilevel mode for setting a temperature in an upper side to be lower than that in a lower side. CONSTITUTION: On the basis of at least a set value for a vehicle interior temperature and a temperature of cool wind fed from a cool wind feeding means 6, an opening for a first door 7 regulating a ratio of air flowing in a first flow passage and a second flow passage is computed, while on the basis of the set value for the vehicle interior temperature, a vehicle exterior temperature, a quantity of solar radiation, and a vehicle interior temperature, a target ventilator blowout wind temperature is computed, and in a bilevel mode, in which warm wind is blown out from a foot blowout port 11 while cool wind is blown out from a ventilator 10, control is carried out so as to accomplish the computed opening for the first door 7. On the basis of the computed target ventilator blowout wind temperature, an opening for the second door 17 regulating a flow rate of the cool wind is controlled.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle air conditioner,
In particular, it improves the air-conditioning characteristics of head cold foot heat in the bilevel mode.

[0002]

[Prior art and its problems] A fresh vent flow path is provided to blow out the cool air that has passed through the evaporator directly from the ventilator, and the cool air is blown from the ventilator while blowing warm air from the foot outlet (hereinafter referred to as "bi-level"). A vehicular air-conditioning system having a mode (known as "mode") is known (for example, Nissan New Model Manual Y3).
2-1 Issued June 1991). A fresh vent door is provided in the fresh vent passage, and in the bi-level mode, the fresh vent door is fully opened to introduce cool air from the evaporator. Normally, in the foot blowout mode and the ventilator blowout mode, the opening of the air mix door is adjusted to adjust the amount of cool air that has passed through the evaporator through the heater core, and the temperature of the blown air into the vehicle compartment is adjusted. On the other hand, in the bi-level mode that controls the temperature of the head cold foot heat, the fresh vent door is fully opened, and the cool air that has passed through the evaporator and the air whose temperature is adjusted by the air mix door are mixed and blown out from the ventilator. Only hot air whose temperature is adjusted by the air mix door is blown out from the room. FIG. 8 shows the blown-air temperature characteristics with respect to the opening degree of the air mix door in the bilevel mode. The solid line in the figure indicates the foot blown air temperature, and the broken line indicates the ventilator blown air temperature. In bi-level mode, the fresh vent door is set to fully open, and the air whose temperature is controlled by the air mix door and the cool air introduced directly from the evaporator through the fresh vent flow path are mixed, so the air blown out from the ventilator The temperature is lower than the temperature of the air-only foot blown air whose temperature is controlled by the air mix door.

However, in the conventional vehicle air conditioner, the amount of cold air introduced from the fresh vent flow path is small, and the fresh vent door is controlled only when it is fully opened or fully closed. Therefore, as shown in FIG. If the temperature difference between the hot air blown from the outlet and the cool air blown from the ventilator is small and the insolation hits the face in the middle outside temperature, lower the ventilator air temperature to cool the wind on the passenger's face. If you try to blow it out, there is a problem that the temperature of the blown air at the foot outlet will also drop.

It is an object of the present invention to provide a vehicle air conditioner with improved air conditioning characteristics for cold head and foot heat in the bilevel mode.

[0005]

In order to achieve the above object, the invention of claim 1 bypasses the air heating means and a first flow path provided with air heating means downstream of the cold air blowing means. A second flow path and a third flow path for directly guiding the cool air sent from the cool air blowing means to the ventilator, and by a first door provided upstream of the first flow path and the second flow path. By adjusting the ratio of the air flowing through the first flow path and the second flow path to blow out temperature-controlled air from the ventilator and / or the foot air outlet, and by the second door provided in the third flow path. An air conditioning unit that adjusts the flow rate of cold air, a temperature setting unit that sets the vehicle interior temperature, an outside air temperature detection unit that detects the vehicle exterior temperature, an inside air temperature degree detection unit that detects the vehicle interior temperature, and a solar radiation amount. Means for detecting the amount of solar radiation Based on the cold air temperature detecting means for detecting the temperature of the cold air sent from the air blowing means, at least the passenger compartment temperature set by the temperature setting means, and the cold air temperature detected by the cold air temperature detecting means, First door opening calculation means for calculating the opening of the door, vehicle interior temperature set by the temperature setting means, vehicle exterior temperature detected by the outside air temperature detection means, and solar radiation amount detection means Based on the amount of solar radiation and the vehicle interior temperature detected by the inside air temperature detecting means, a ventilator blowout air temperature calculating means for calculating a target ventilator blowout air temperature, and the foot outlet while blowing cool air from the ventilator In the bi-level mode in which hot air is blown out of the first door, the opening of the first door is controlled based on the calculation result of the first door opening calculating means. Rutotomoni, and control means for controlling the opening of the second door on the basis of the calculated target ventilator outlet air temperature by the ventilator outlet air temperature calculating means. The vehicle air conditioner according to claim 2, wherein the control means linearly expresses a characteristic curve of the ventilator blowing air temperature with respect to the opening of the first door, the cold air temperature detected by the cold air temperature detecting means, and the opening of the second door. The opening degree of the second door is controlled based on the linear approximation curve and the target ventilator blowing air temperature. In the vehicle air conditioner according to claim 3, the first bilevel mode and the second bilevel mode in which the amount of air blown out from the ventilator is different by the control means.
The target ventilator blowing air temperature is set differently in the bi-level mode.

[0006]

According to the vehicle air conditioner of the present invention, the ratio of the air flowing through the first flow passage and the second flow passage is based on at least the set value of the vehicle interior temperature and the temperature of the cool air sent from the cool air blowing means. The opening of the first door that adjusts the temperature is calculated, and the target ventilator blowing air temperature is calculated based on the set value of the vehicle interior temperature, the vehicle exterior temperature, the amount of solar radiation, and the vehicle interior temperature, while blowing cool air from the ventilator. In the bi-level mode in which hot air is blown out from the foot outlet, the second door is controlled so that the first door has the calculated opening degree and the flow rate of the cool air is adjusted based on the calculated target ventilator blown air temperature. Control the opening of. In the vehicle air conditioner according to claim 2, the characteristic curve of the ventilator blown air temperature with respect to the opening of the first door, the temperature of the cool air sent from the cool air blowing means, and the opening of the second door is linearly approximated, and this linear approximation is performed. The opening degree of the second door is controlled based on the curve and the target ventilator blowing air temperature. In the vehicle air conditioner according to the third aspect, different target ventilator blowing air temperatures are set in the first bi-level mode and the second bi-level mode, respectively.

[0007]

FIG. 1 is a sectional view showing the structure of an air conditioning duct of one embodiment. On the upstream side of the air conditioning duct 1 provided in the vehicle compartment, an inside air introduction port 2 for introducing air in the vehicle interior and an outside air introduction port 3 for introducing outside air are provided. An intake door 4 driven by an actuator (described later) is provided at a branch portion of these inlets 2 and 3 to open and close the inside air inlet 2 and the outside air inlet 3 at an arbitrary ratio. The blower fan 5 installed upstream of the air conditioning duct 1 is a blower motor 5
driven by m, and introduces air from the inside air inlet 2 and the outside air inlet 3 according to the opening / closing ratio of the intake door 4,
The air is blown to the evaporator 6 arranged downstream of the air conditioning duct 1. The evaporator 6 is an endothermic heat exchanger that absorbs heat from the air blown by the blower fan 5 into the refrigerant to create cold air.

An air mix door 7 is provided downstream of the evaporator 6, and the downstream of the air mix door 7 is branched into two flow paths. The first channel is the heater core 8
Is a flow path for warming the cool air, and the second flow path is a flow path that bypasses the heater core 8. Air mix door 7
Is opened and closed by an actuator (described later) to adjust the ratio of the air passing through the heater core 8 and the air bypassing the heater core 8. The air that has been absorbed by the evaporator 6 and cooled is partly heated by passing through the heater core 8 in accordance with the opening degree of the air mix door 7, and the rest is blown out as cold air bypassing the heater core 8. .
That is, the ratio of cold air to warm air is adjusted according to the opening of the air mix door 7. The opening degree Xdsc of the air mix door 7 is 0% (fully closed, Xdsc = 0) when the air mix door 7 is at the alternate long and short dash line position, and at this time, the ratio of cold air to warm air is 100%. On the other hand, the opening Xdsc when the air mix door 7 is at the illustrated position is 100% (fully open, Xdsc = 1), and at this time, the ratio of the cold air and the hot air is 100%.

An air mix chamber 9 is provided downstream of the air mix door 7, where cold air and warm air are mixed to produce temperature-controlled conditioned air. Downstream of the air mix chamber 9, a ventilator 10 that blows conditioned air toward the upper body of the occupant, a foot outlet 11 that blows conditioned air toward the feet of the occupant, and a defroster blow that blows conditioned air toward the windshield. An outlet 12 is installed. A ventilator door 13, a foot door 14 and a defroster door 1 are provided at the outlets 10 to 12, respectively.
5 and an actuator (described later) for driving each door are provided.

On the other hand, downstream of the evaporator 6, there is provided a third flow passage 16 or a fresh vent flow passage 16 for directly guiding the cool air passing through the evaporator 6 to the ventilator 10. The fresh vent passage 16 is provided with a fresh vent door 17 for adjusting the passing air volume, and is fully closed (opening XBL =
It is driven from 0) to full open (opening XBL = 1). The cool air introduced from the fresh vent channel 16 is mixed with the conditioned air from the air mix chamber 9 and blown out from the ventilator 10.

FIG. 2 is a block diagram showing the electrical structure of an embodiment. The controller 20 is composed of a microcomputer and its peripheral parts, and executes a control program described later to perform air conditioning control. Various switches and sensors are connected to the controller 20. The switch SW1 is a main switch for operating the air conditioner, and the switch SW2 is an automatic air conditioner switch for setting the automatic air conditioning mode. The room temperature setting device 21 is a setting device for setting the target temperature in the vehicle compartment. The outside air temperature sensor 22 detects the outside air temperature Ta, and the inside air temperature sensor 23 detects the vehicle interior temperature (hereinafter, referred to as inside temperature) T.
detect inc. Further, the solar radiation sensor 24 detects the solar radiation amount Qsun, and the suction temperature sensor 25 detects the suction air temperature Tint immediately after passing through the evaporator 6. A compressor 26 and drivers for driving various actuators are also connected to the controller 20. The driver 7d drives the actuator 7m of the air mix door 7. The opening Xds for the air mix door 7.
An opening sensor 7s for detecting c is provided, and the opening sensor 7s is an air mix door actuator 7m.
It is driven in conjunction with. Further, the driver 17d drives the actuator 17m of the fresh vent door 17. The fresh vent door 17 is provided with an opening sensor 17s for detecting the opening XBL.
7s is driven in conjunction with the fresh vent door actuator 17m. Furthermore, the drivers 13d and 14
d and 15d drive the ventilator door actuator 13m, the foot door actuator 14m, and the defroster door actuator 15m, respectively. Driver 4
d drives the intake door actuator 4m described above, and the driver 5d drives the blower motor 5m described above.

FIG. 3 is a flowchart showing an air conditioning control program of the controller 20. The operation of the embodiment will be described with reference to this flowchart. Controller 2
0 is the main switch SW1
When is input, execution of this control program is started.
In step 1, room temperature set value Tptc and inside air temperature Ti
nc, outside air temperature Ta, intake air temperature Tint, insolation Q
Set the initial values of sun, air mix door opening Xdsc, fresh vent door opening XBL, and various operation switches. In step 2, fail-safe processing is performed for backup when the microcomputer runs out of control, and the process proceeds to step 3, where each sensor 22-25, 7s,
Each detected value is input from 17s. Step 4
Then, the outside air temperature Ta detected by the outside air temperature sensor 22 is corrected to obtain a correction value T'a. Normally, the outside air temperature sensor 22 is attached to the radiator core support in the engine room, so if the detected value suddenly rises due to the heat effect of the radiator during idling immediately after running, the recognition temperature of the controller 20 will slowly increase. And correct it so that it rises. Further, in step 5, the amount of solar radiation Qsun detected by the solar radiation sensor 24 is corrected to obtain a correction value Q'sun. For example, when the detected value of the amount of solar radiation Qsun changes abruptly when entering or leaving a tunnel, the amount of solar radiation recognized by the controller 20 is corrected so as to change slowly. In step 6, the outside temperature Ta
The room temperature set value Tptc is corrected according to
get c. For example, the higher the outside air temperature Ta, the lower the room temperature set value, and the lower the outside air temperature Ta, the higher the room temperature set value.

In step 7, the intake air temperature Ti
nt, room temperature set value T'ptc, solar radiation Q'sun, etc., based on thermal environment conditions, the air mix door opening Xdsc for obtaining the target foot blown air temperature is calculated, and the driver is operated according to the calculated opening Xdsc. The air mix door 7 is driven and controlled by 7d and the actuator 7m. Thereby, the room temperature set value T'ptc set in the room temperature setting device 21, that is, the conditioned air having the target foot blown air temperature is blown from the foot outlet 11. Step 8
Then, the variable capacity control of the compressor 26 is performed based on the setting state of the defrost mode, the outside air temperature Ta, and the like. When the intake air temperature Tint is lower than a predetermined temperature, the compressor 2 is used to prevent the evaporator 6 from freezing.
Stop 6 Further, when the vehicle is rapidly accelerated, the compressor 26 is stopped to reduce the load on the engine. In step 9, a subroutine described later is executed to control the opening degree of the fresh vent door 17. This fresh vent control will be described later. In subsequent step 10, when the intake air temperature Tint is equal to or lower than a predetermined value, the engine speed is reduced to a normal value to reduce idle noise.

In step 11, the outlet air temperature Tof is calculated based on the air mix door opening Xdsc, the intake air temperature Tint, the solar radiation amount correction value Q'sun, etc., and the outlet is determined according to the outlet air temperature Tof. , And controls the drivers 13d to 15d and actuators 13m to 15m of the respective doors to drive the air outlets 10 to 12. Generally, when the outside air temperature Ta is low, the foot blowout mode is set, but when the outside air temperature Ta is very low, the defrost blowing mode is set to prevent the window shield from fogging. In addition, when the outlets are manually set, they are given priority. In step 12, the intake door 4 is driven by the driver 4d and the actuator 4m in accordance with the blowing air temperature Tof calculated in the above step to set the outside air introduction, the inside air circulation, or the half outside air introduction. In addition, when the outside temperature is low, priority is given to the introduction of outside air to prevent fogging of the window shield.
If the suction port is manually set by an inside air circulation switch or an outside air introduction switch (not shown), they are prioritized. In step 13, the air mix door opening Xds
The speed of the blower fan 5 is determined according to c, the outlet mode, the amount of solar radiation Qsun, etc., and the driver 5d and the motor 5m are drive-controlled. Next, in step 14, a diagnostic program (not shown) is executed to perform self-diagnosis of the apparatus, and if there is an abnormality, a predetermined process is performed, then the process returns to step 2 and the above-described process is repeated.

FIG. 4 is a flow chart showing a fresh vent control routine. According to this flowchart,
The fresh vent control of the embodiment will be described. Step 2
In step 1, it is determined whether or not the bilevel mode is set. If the bilevel mode is set, the process proceeds to step 23, and if not, the process proceeds to step 22.
If not in the bi-level mode, in step 22, processing such as defrost mode is performed. When the bi-level mode is set, in step 23, the opening sensor 7s
The air mix door opening Xdsc is read from. This air mix door opening Xdsc is the intake air temperature T
The opening degree is calculated in step 7 based on thermal environment conditions such as int, room temperature set value T'ptc, and solar radiation amount Q'sun, and set by the actuator 7m. In addition,
In the bi-level mode, the room temperature set value T'ptc becomes the target foot blowing air temperature. In the following step 24, the target ventilator blowout air temperature Tvent is calculated by the following equation based on the set room temperature T′ptc, the outside air temperature T′a, the solar radiation amount Q′sun and the inside air temperature Tinc described above.

## EQU1 ## Tvent = (a + d) T'ptc + bT'a
+ CQ'sun + dTinc + e Here, a, b, c, d, and e are constants. Step 2
5, open sensor 17s to fresh vent door 1
The opening XBL of 7 is read and the process proceeds to step 26. In step 26, it is determined whether or not the first bi-level mode (B / L1) is set. When the B / L1 mode is set, the process proceeds to step 27, and the target ventilator blowout air temperature Tvent is set to a predetermined value. Correct with α1. The correction value α1 is, for example, about −1.5 ° C. On the other hand, B
The / L1 mode means that when the second bi-level mode (B / L2) in which the air volume of the ventilator 10 is different, that is, the air volume ratio of the ventilator 10 and the foot outlet 11 is set, the routine proceeds to step 29, where the target ventilator blowout air temperature is set. Tvent is corrected with a predetermined value α2. The correction value α
2 is 0, for example.

FIG. 5 shows the blown air temperature characteristic with respect to the air mix door opening and the blown air temperature characteristic with respect to the fresh vent door opening. The second quadrant in the figure shows the foot blowout air temperature (solid line) and the ventilator blowout air temperature (broken line) with respect to the air mix door opening Xdsc when the fresh vent door is closed. Further, the first quadrant shows the temperature characteristics of the air blown from the ventilator 10 when the fresh vent door 17 is opened from the typical ventilator air temperature when the fresh vent is closed, which is indicated by the broken line in the second quadrant. . These curves are for the intake air temperature Tint,
It is measured under predetermined conditions such as the blower fan speed, the hot water temperature of the heater core and the hot water flow rate. In order to blow out conditioned air having different target temperatures from the ventilator 10 and the foot outlet 11, the fresh vent door 17 is drive-controlled as follows. (1) When the air mix door opening is set based on the room temperature set value T'ptc, that is, the target foot blowout air temperature in the bi-level mode at a certain intake air temperature Tint, the ventilator blowout air temperature when the fresh vent is closed becomes Decided. (2) The intersection of the fresh vent door opening XBL read from the opening sensor 17s and the ventilator outlet air temperature curve corresponding to the ventilator outlet air temperature when the fresh vent is closed, that is, the ventilator at the current fresh vent door opening XBL. The blown air temperature estimated value T'vent is obtained. (3) Assuming that the target ventilator blowout air temperature Tvent calculated by the formula 1 is compared with the ventilator blowout air temperature estimated value T'vent at the current fresh vent door opening XBL, the deviation SBL between them is obtained. (4) The driver 17d and the motor 17m are controlled according to the deviation SBL to drive the fresh vent door 17. The fresh vent door opening XBL is obtained from the intersection of the ventilator blowout air temperature curve corresponding to the ventilator blowout air temperature when the fresh vent is closed, and the target ventilator blowout air temperature Tvent, and the driver 17d and the motor 17m are controlled to control the fresh air. The vent door 17 may be driven.

In order to treat the characteristic shown in FIG. 5 by a mathematical expression, the estimated value T'vent of the ventilator blown air temperature is obtained by approximating the characteristic curve shown in the first quadrant with a polygonal line.

## EQU2 ## T'vent = (Tw-Tint) (Fb.X
BL + Gb) + Tint Here, Tw is the temperature of the hot water passing through the heater core 8,
Fb and Gb are calculation coefficients of the ventilator blowing air temperature. Note that Fb and Gb are the hot water temperature Tw in the steady state of 82.
Assuming that the intake air temperature Tint is 0 ° C., the estimated value T′vent of the ventilator blown air temperature is

[Equation 3] Since T'vent = 82 (Fb · XBL + Gb), it can be obtained from the outlet temperature T'vent, the opening XBL and the characteristic curve diagram. The calculation coefficients Fb and Gb of the ventilator outlet air temperature are the air mix door. Opening Xdsc
Therefore, the coefficients Fb and Gb are approximated by the following equation.

## EQU4 ## Fb = aF.Xdsc + bF, Gb = aG.Xdsc + bG where aF, bF, aG, bG are constants. To obtain these constants, the air mix door opening Xd is plotted on the horizontal axis.
Sc and Fb and Gb on the vertical axis are plotted on a graph. This graph is approximated to a broken line to create map data of constants aF, bF, aG and bG shown in Tables 1 to 4. In addition,
As can be seen from the first quadrant of the characteristic diagram, Fb and Gb are curved at the fresh vent door opening X21, so
Map data is also divided into two areas. Table 1 is B / L
Fb map data in 1 mode, Table 2 shows B / L1
The map data of Gb in mode is shown.

[Table 1]

[Table 2] Further, Table 3 shows Fb map data in the B / L2 mode, and Table 4 shows Gb map data in the B / L2 mode.

[Table 3]

[Table 4] Note that these map data are stored in advance in the memory inside the controller 20.

Returning to the fresh vent control routine of FIG. 4, when the B / L1 mode is set, step 2
8 shows the constant a in the B / L1 mode according to Table 1 and Table 2.
Determine F, bF, aG, bG. When the B / L2 mode is set, the constants aF, bF, aG and bG in the B / L2 mode are determined in step 30 according to Table 3 and Table 4. In a succeeding step 31, the calculation coefficients Fb, Gb of the ventilator blowout air temperature are calculated by Equation 4 based on the constants aF, bF, aG, bG, and the coefficients Fb, Gb, the fresh vent door opening XBL, the intake air temperature are calculated. Tint
Based on the hot water temperature Tw and the warm water temperature Tw, the estimated value T'vent of the ventilator blown air temperature is calculated by the above-described mathematical expression 2. In step 32, the deviation SBL between the target ventilator blowing air temperature Tvent and its estimated value T'vent
Is calculated by the following formula.

## EQU00005 ## SBL = Tvent-T'vent = Tvent- (Tw-Tint) (Fb.XBL + Gb) -Tint In step 33, the driver 17 is operated according to the deviation SBL.
d and the motor 17m are controlled, and the fresh vent door 17
Drive. That is, when the deviation SBL is less than -2, the process proceeds to step 34, the fresh vent door 17 is driven in the closing direction, and when the deviation SBL is greater than 2, step 3 is performed.
5, the fresh vent door 17 is driven in the opening direction. When the deviation SBL is greater than or equal to -2 and less than or equal to 2, the fresh vent door 17 is not driven and the current opening is maintained.

FIG. 6 shows the result of fresh vent control in the bilevel mode of the embodiment. When the amount of solar radiation suddenly increases at time t1 as shown in (a), the ventilator blowing air temperature decreases as shown in (b), but the foot blowing air temperature does not change. In other words, even if the occupant's face is suddenly exposed to the sunlight in bi-level mode, the ventilator blowout air temperature is reduced while keeping the blowout air temperature at the feet constant, so the thermal sensation of the face does not change. , Comfortable head cold foot heat air conditioning is achieved.

FIG. 7 shows the temperature characteristics of blown air with respect to the opening degree of the air mix door in the bi-level mode of the embodiment. The solid line in the figure indicates the foot blown air temperature, and the broken line indicates the ventilator blown air temperature. Compared with the temperature control characteristics of the conventional vehicle air conditioner shown in FIG. 8, there is a large temperature difference between the foot blowout air temperature and the ventilator blowout air temperature, and since the temperature difference can be made variable, the amount of solar radiation in the bi-level mode and Even when environmental conditions such as the outside temperature change, it is possible to supply the ventilator blowout air with the optimum temperature.

In this way, the air mix door opening Xdsc is calculated based on the thermal environment conditions such as the intake air temperature Tint, the room temperature set value T'ptc, and the solar radiation amount Q'sun, and the room temperature set value T'ptc is calculated. The target ventilator blowout air temperature is calculated based on the outside air temperature T'a, the amount of solar radiation Q'sun, and the inside air temperature Tinc, and the air is blown in the bilevel mode in which the cool air is blown from the ventilator 10 and the warm air is blown from the foot outlet 11. The mix door 7 is controlled to have the calculated opening, and the opening XBL of the fresh vent door 17 is controlled based on the calculated target ventilator blown air temperature.
Fresh vent flow path 16 compared to conventional vehicle air conditioners
In addition to increasing the flow rate by enlarging itself, the temperature difference between the foot blowing air temperature and the ventilator blowing air temperature can be made large, and the temperature difference is variable, and in bi-level mode environmental conditions such as insolation and outside air temperature. Even if the temperature changes, it is possible to supply the ventilator blown air of the optimum temperature while keeping the foot blown air temperature constant. Further, a characteristic curve of the ventilator blowout air temperature with respect to the air mix door opening Xdsc, the intake air temperature Tint and the fresh vent door opening XBL is linearly approximated, and the fresh vent door is based on the linear approximation curve and the target ventilator blown air temperature. Since the opening degree XBL of 17 is controlled, the load of the arithmetic processing of the controller 20 is reduced, the arithmetic processing time is shortened, and the control response can be improved. Furthermore, the air volume from the ventilator is different B
Since different target ventilator blowing air temperatures are set for the / L1 mode and the B / L2 mode respectively,
It is possible to supply the optimal ventilator blown air according to the air volume. Furthermore, although the blower fan 5 and the evaporator 6 are used as the blower means in the above-described embodiment, the blower means may be only the blower fan 5.

In the structure of the above embodiment, the blower fan 5 and the evaporator 6 serve as a cool air blowing means, the heater core 8 serves as an air heating means, and the air mix door 7 serves as the first.
The fresh vent door 17 is the second door, the room temperature setting device 21 is the temperature setting means, the outside air temperature sensor 22 is the outside air temperature detecting means, the inside air temperature sensor 23 is the inside air temperature detecting means, and the solar radiation sensor 24 is the solar radiation. The suction temperature sensor 25 constitutes a cold air temperature detection means, and the microcomputer 20 constitutes a first door opening calculation means, a ventilator blown air temperature calculation means and a control means.

[0023]

As described above, according to the invention of claim 1, the first flow path and the second flow path are based on at least the set value of the vehicle compartment temperature and the temperature of the cool air sent from the cool air blowing means. The opening of the first door that adjusts the ratio of the air flowing in the road is calculated, and the target ventilator blowing air temperature is calculated based on the set value of the vehicle interior temperature, the vehicle exterior temperature, the amount of solar radiation, and the vehicle interior temperature. , In the bi-level mode in which warm air is blown from the foot outlet while blowing cool air from the ventilator, the first door is controlled to have the calculated opening degree, and the cool air is blown based on the calculated target ventilator blown air temperature. Since the opening degree of the second door for adjusting the flow rate is controlled, the fresh vent flow path itself is made larger than that of the conventional vehicle air conditioner to increase the flow rate, and the foot blown air temperature and the vent air flow are reduced. In addition to being able to take a large temperature difference from the blower air temperature, the temperature difference is variable, and the foot air temperature remains constant even when environmental conditions such as the amount of solar radiation or the outside temperature change in bi-level mode. It is possible to supply the ventilator blown air with the optimum temperature.
Further, according to the invention of claim 2, the characteristic curve of the ventilator blown air temperature with respect to the opening of the first door, the temperature of the cold air sent from the cool air blowing means and the opening of the second door is linearly approximated, and this linear Since the opening of the second door is controlled based on the approximate curve and the target ventilator blowing air temperature, the calculation processing load on the controller is reduced and the calculation processing time is shortened, improving control response. it can. Further, according to the invention of claim 3, different target ventilator blowing air temperatures are set in the first bi-level mode and the second bi-level mode in which the air volume from the ventilator is different, so that the optimum ventilator according to the air volume is set. A blowing air can be supplied.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing the configuration of an air conditioning duct of one embodiment.

FIG. 2 is a block diagram showing an electrical configuration of one embodiment.

FIG. 3 is a flowchart showing an air conditioning control program of a controller.

FIG. 4 is a flowchart showing a fresh vent control routine.

FIG. 5 is a diagram showing an outlet air temperature characteristic with respect to an air mix door opening and an outlet air temperature characteristic with respect to a fresh vent door opening.

FIG. 6 is a diagram showing a fresh vent control result in a bi-level mode according to the embodiment.

FIG. 7 is a diagram showing blown air temperature characteristics with respect to the opening degree of the air mix door in the embodiment.

FIG. 8 is a view showing a blown air temperature characteristic with respect to an opening degree of an air mix door of a conventional vehicle air conditioner.

[Explanation of symbols]

 1 Air Conditioning Duct 2 Inside Air Inlet 3 Outside Air Inlet 4 Intake Door 4d Driver 4m Actuator 5 Blower Fan 5d Driver 5m Blower Motor 6 Evaporator 7 Air Mix Door 7d Driver 7m Actuator 7s Opening Sensor 8 Heater Core 9 Air Chamber 10 Ventilator 11 Foot Outlet 12 Defroster outlet 13 Ventilator door 13d Driver 13m Actuator 14 Foot door 14d Driver 14m Actuator 15 Defroster door 15d Driver 15m Actuator 16 Fresh vent channel 17 Fresh vent door 17d Driver 17m Actuator 17s Opening sensor 20 Controller 22 Outside room temperature setting device Air temperature sensor 23 Temperature sensor 24 Solar radiation sensor 25 Suction temperature sensor 26 Compressor SW1 Main switch SW2 Auto air conditioner switch

Claims (3)

[Claims] 1. A first flow path provided with an air heating means downstream of the cool air blowing means, a second flow path bypassing the air heating means, and the cool air sent from the cold air blowing means directly to a ventilator. A third flow path for guiding, and a first door provided upstream of the first flow path and the second flow path adjusts a ratio of air flowing through the first flow path and the second flow path. An air conditioning unit that blows out temperature-controlled air from the ventilator and / or the foot outlet, and adjusts the flow rate of cold air by the second door provided in the third flow path, and a temperature setting means that sets the vehicle interior temperature. The outside air temperature detecting means for detecting the outside temperature of the vehicle compartment, the inside air temperature detecting means for detecting the inside temperature of the vehicle compartment, the insolation amount detecting means for detecting the insolation amount, and the temperature of the cold air sent from the cold air blowing means Cold air temperature detection hand to detect A first door opening degree calculating means for calculating the opening degree of the first door based on at least the vehicle interior temperature set by the temperature setting means and the cold air temperature detected by the cold air temperature detecting means, The vehicle interior temperature set by the temperature setting means, the vehicle exterior temperature detected by the outside air temperature detecting means, the solar radiation amount detected by the solar radiation amount detecting means, and the vehicle detected by the inside air temperature detecting means. Based on the room temperature and
A ventilator blowout air temperature calculating means for calculating a target ventilator blowout air temperature; and a bilevel mode in which warm air is blown out of the foot outlet while blowing out cool air from the ventilator, based on the calculation result of the first door opening degree calculating means. The first
A control means for controlling the opening degree of the door and controlling the opening degree of the second door based on the target ventilator blowing air temperature calculated by the ventilator blowing air temperature calculating means. Air conditioner. 2. The vehicle air conditioner according to claim 1, wherein the control unit ventilator blowout with respect to an opening of the first door, a cold air temperature detected by the cold air temperature detecting unit, and an opening of the second door. A vehicle air conditioner characterized by linearly approximating a characteristic curve of wind temperature, and controlling the opening of the second door based on the linear approximation curve and the target ventilator blowing air temperature. 3. The vehicle air conditioner according to claim 1 or 2, wherein the control means has different targets in a first bi-level mode and a second bi-level mode in which the amount of air blown from the ventilator is different. A ventilator air conditioner that sets the temperature of blown air.