JP3324335B2 - Vehicle air conditioner - Google Patents

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, the present invention is to improve the air conditioning characteristics of head and foot heat in the bi-level mode.

[0002]

2. Description of the Related Art An air-conditioning mode (hereinafter referred to as a bi-level) in which a fresh vent channel is provided for allowing cool air that has passed through an evaporator to blow directly from a ventilator, and cool air is blown from a ventilator while blowing warm air from a foot outlet. An air conditioner for a vehicle equipped with a vehicle mode (for example, a new model Nissan Y3)
2-1 issued June 1991). A fresh vent door is provided in the fresh vent channel. In the bi-level mode, the fresh vent door is fully opened, and cool air is introduced from the evaporator. Normally, in the foot blow mode and the ventilator blow 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, the fresh vent door is fully opened, the cool air that has passed through the evaporator and the air that has been temperature-controlled by the air mix door are mixed and blown out from the ventilator, and the foot outlet Only hot air whose temperature has been adjusted by the air mix door is blown out of the air. FIG. 8 shows the outlet air temperature characteristics with respect to the air mix door opening in the bilevel mode. The solid line in the figure indicates the temperature of the air blown out from the foot, and the broken line indicates the temperature of the air blown out from the ventilator. In the bi-level mode, the fresh vent door is set to fully open, and the air temperature controlled by the air mix door is mixed with the cool air introduced directly from the evaporator through the fresh vent channel, so that the air blown out from the ventilator The temperature is lower than the temperature of the air-only foot blown air temperature-controlled by the air mix door.

However, in the conventional vehicle air conditioner, the amount of cool air introduced from the fresh vent passage is small, and the fresh vent door is controlled only when it is fully opened and fully closed. Therefore, as shown in FIG. If the temperature difference between the warm air blown out of the exit and the cool air blown out of the ventilator is small, and the sun shines on the face at an intermediate outside temperature, lower the temperature of the ventilator blown air to cool the occupant's face. If the air is blown out, there is a problem that the temperature of the air blown out of the foot outlet also decreases.

It is an object of the present invention to provide an air conditioner for a vehicle which has improved air conditioning characteristics of head and foot heat in a bi-level mode.

[0005]

In order to achieve the above object, according to a first aspect of the present invention, there is provided a first flow path provided with air heating means downstream of a cool air blowing means, and bypassing the air heating means. A second flow path, and a third flow path that directly guides the cool air sent from the cool air blowing means to the ventilator, and a first door provided upstream of the first flow path and the second flow path. The ratio of the air flowing through the first flow path and the second flow path is adjusted to blow out the temperature-controlled air from the ventilator and / or the foot outlet, and the second door provided in the third flow path. An air conditioning unit for adjusting the flow rate of cool air, temperature setting means for setting the temperature inside the vehicle, outside temperature detecting means for detecting the temperature outside the vehicle, inside temperature detecting means for detecting the temperature inside the vehicle, and detecting the amount of solar radiation Means for detecting the amount of solar radiation A cool air temperature detecting means for detecting a temperature of the cool air sent from the blowing means, and the first air temperature based on at least a vehicle interior temperature set by the temperature setting means and a cool air temperature detected by the cool air temperature detecting means. First door opening calculating means for calculating the degree of opening of the door, a vehicle interior temperature set by the temperature setting means, a vehicle outside temperature detected by the outside air temperature detecting means, and a detection by the solar radiation amount detecting means. A ventilator blow-out air temperature calculating means for calculating a target ventilator blow-out air temperature based on the measured amount of solar radiation and the vehicle interior temperature detected by the inside air temperature detecting means, and the foot air outlet while blowing cool air from the ventilator. Controlling the opening degree of the first door based on the calculation result of the first door opening degree calculation means in a bi-level mode in which warm air is blown from 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. 3. The vehicle air conditioner according to claim 2, wherein the control unit linearly changes a characteristic curve of the ventilator blown air temperature with respect to the opening degree of the first door, the cold air temperature detected by the cold air temperature detecting means, and the opening degree of the second door. The opening degree of the second door is controlled based on the approximated linear approximation curve and the target ventilator blown air temperature. The vehicle air conditioner according to claim 3, wherein the control means controls the first bi-level mode and the second bi-level mode in which the amount of air blown from the ventilator is different.
A different target ventilator outlet air temperature is set for each of 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 path and the second flow path 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. While calculating the opening degree of the first door, the target ventilator outlet 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 the warm air is blown from the foot outlet, the second door controls the first door to have the calculated opening degree and adjusts the flow rate of the cool air based on the calculated target ventilator blown air temperature. Control the opening degree. According to the vehicle air conditioner of the present invention, the characteristic curve of the ventilator air temperature with respect to the opening degree of the first door, the temperature of the cool air sent from the cool air blowing means, and the opening degree of the second door is linearly approximated. The degree of opening of the second door is controlled based on the curve and the target ventilator air temperature. In the vehicle air conditioner according to the third aspect, different target ventilator air outlet temperatures are set in the first bilevel mode and the second bilevel mode.

[0007]

FIG. 1 is a sectional view showing the structure of an air conditioning duct according to one embodiment. On the upstream side of the air conditioning duct 1 provided in the vehicle interior, 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 (to be described later) is provided at a branch portion between the inlets 2 and 3, and opens and closes the inside air inlet 2 and the outside air inlet 3 at an arbitrary ratio. A blower fan 5 installed upstream of the air conditioning duct 1 has a blower motor 5
m, and air is introduced 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 a heat-absorbing heat exchanger that absorbs heat from the air blown by the blower fan 5 into a refrigerant to generate cool 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
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), and adjusts the ratio of air passing through the heater core 8 and air bypassing the heater core 8. A part of the air that has been cooled by absorbing heat by the evaporator 6 passes through the heater core 8 and is heated according to the opening degree of the air mix door 7, and the rest is blown out with the cool air bypassing the heater core 8. .
That is, the ratio between the cool air and the 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 dashed-dotted line position. At this time, the ratio of cold air to warm air is 100% cold air. On the other hand, when the air mix door 7 is at the illustrated position, the opening degree Xdsc is set to 100% (fully opened, Xdsc = 1), and at this time, the ratio of cold air to hot air is 100%.

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

On the other hand, a third flow path, that is, a fresh vent flow path 16 for guiding the cool air passing through the evaporator 6 directly to the ventilator 10 is provided downstream of the evaporator 6. The fresh vent passage 16 is provided with a fresh vent door 17 for adjusting the amount of air passing therethrough, and is fully closed (opening XBL =
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 configuration of the electrical system according to one embodiment. The controller 20 includes a microcomputer and its peripheral components, 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 an automatic air conditioning mode. Further, the room temperature setting device 21 is a setting device for setting a 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 a vehicle interior temperature (hereinafter referred to as an inside air temperature) T
inc is detected. 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. The controller 20 is also connected with a compressor 26 and a driver for driving various actuators. The driver 7d drives the actuator 7m of the air mix door 7. The air mix door 7 has the opening Xds
c is provided, and the opening sensor 7s is provided with an air-mix door actuator 7m.
Driven in conjunction with 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, 14
d and 15d drive a ventilator door actuator 13m, a foot door actuator 14m, and a defroster door actuator 15m, respectively. Driver 4
d drives the above-described intake door actuator 4m, and the driver 5d drives the above-described blower motor 5m.

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
Microcomputer is the main switch SW1
Is started, the execution of this control program is started.
In step 1, the room temperature set value Tptc, the internal temperature Ti
nc, outside air temperature Ta, intake air temperature Tint, solar radiation Q
sun, an air mix door opening Xdsc, a fresh vent door opening XBL, and initial values of various operation switches are set. In step 2, a fail-safe process is performed for backup when the microcomputer runs out of control, and the process proceeds to step 3, where each of the sensors 22 to 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, since the outside temperature sensor 22 is attached to the radiator core support in the engine room, when the detected value rises rapidly due to the influence of the heat of the radiator at the time of idling immediately after traveling, the recognition temperature of the controller 20 slowly decreases. And so as to ascend. 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 exiting a tunnel, the correction is made so that the amount of solar radiation recognized by the controller 20 changes slowly. In step 6, the outside air temperature Ta
The room temperature set value Tptc is corrected in accordance with
Obtain 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 suction air temperature Ti
nt, a room temperature set value T'ptc, an amount of solar radiation Q'sun, and the like, to calculate an air mix door opening Xdsc for obtaining a target foot blown air temperature based on thermal environmental conditions such as a sunshine amount Q'sun, and a driver according to the calculated opening Xdsc. The drive of the air mix door 7 is controlled by the actuator 7d and the actuator 7m. As a result, the room temperature set value T'ptc set in the room temperature setting device 21, that is, the conditioned air having the target foot air temperature is blown out from the foot air outlet 11. Step 8
Then, the variable displacement control of the compressor 26 is performed based on the setting state of the defrost mode, the outside 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. When the vehicle is suddenly 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 of the fresh vent door 17. This fresh vent control will be described later. In the following 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 inlet air temperature Tint, the solar radiation correction value Q'sun, and the like, and the outlet is determined according to the outlet air temperature Tof. The driver controls each of the drivers 13d to 15d and the actuators 13m to 15m to drive the outlets 10 to 12. Generally, when the outside air temperature Ta is low, the foot blowing mode is set. When the outside air temperature Ta is extremely low, the defrost blowing mode is set to prevent fogging of the window shield. If 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 according to the blown air temperature Tof calculated in the above step to set the outside air introduction, inside air circulation, or semi-outside air introduction. If the outside temperature is low, prioritize the introduction of outside air to prevent fogging of the window shield,
If the suction port is manually set by a not-shown inside air circulation switch or outside air introduction switch, those are prioritized. In step 13, the air mix door opening degree Xds
The speed of the blower fan 5 is determined according to c, the outlet mode, the amount of solar radiation Qsun, and the like, and the driver 5d and the motor 5m are drive-controlled. Next, in step 14, a diagnostic program (not shown) is executed to perform a self-diagnosis of the apparatus. If there is an abnormality, predetermined processing is performed, and then the process returns to step 2 and the above-described processing is repeated.

FIG. 4 is a flowchart 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 the bi-level mode is set. If the bi-level mode is set, the process proceeds to step 23; otherwise, the process proceeds to step 22.
If the mode is not the bilevel mode, a process such as a defrost mode is performed in step S22. When the bi-level mode is set, in step 23, the opening sensor 7s
The air mixing door opening degree Xdsc is read from. The air mixing door opening Xdsc is determined by the suction air temperature T
Int, room temperature set value T'ptc, insolation Q'sun, etc. are calculated in step 7 based on the thermal environment conditions such as insolation, and the opening degree set by actuator 7m. In addition,
In the bi-level mode, the room temperature set value T'ptc becomes the target foot outlet wind temperature. In the following step 24, based on the above-mentioned set room temperature T'ptc, outside air temperature T'a, solar radiation Q'sun, and inside air temperature Tinc, the target ventilator outlet air temperature Tvent is calculated by the following equation.

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

FIG. 5 shows the outlet air temperature characteristics with respect to the air mix door opening and the outlet air temperature characteristics with respect to the fresh vent door opening. The second quadrant in the figure shows the foot outlet air temperature (solid line) and the ventilator outlet air temperature (dashed line) with respect to the air mix door opening Xdsc when the fresh vent door is closed. The first quadrant shows the temperature characteristics of the blown air from the ventilator 10 when the fresh vent door 17 is opened from the representative ventilator blown air temperature when the fresh vent is closed, indicated by a broken line in the second quadrant. . Note that these curves represent the suction air temperature Tint,
It is measured under predetermined conditions, such as blower fan speed, hot water temperature of the heater core, and hot water flow rate. In order to blow out conditioned air at different target temperatures from the ventilator 10 and the foot outlet 11, respectively, the drive of the fresh vent door 17 is controlled as follows. (1) At a certain intake air temperature Tint, if the air mix door opening is set based on the room temperature set value T'ptc, that is, the target foot airflow temperature in the bi-level mode, the ventilator airflow temperature when the fresh vent is closed is reduced. 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 blowout air temperature estimation value T'vent is obtained. (3) Assuming that the target ventilator outlet air temperature Tvent calculated by Equation 1 is used, the estimated ventilator outlet air temperature T′vent at the current fresh vent door opening XBL is compared to obtain a deviation SBL between the two. (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 air temperature curve corresponding to the ventilator air temperature when the fresh vent is closed and the target ventilator air temperature Tvent, and the driver 17d and the motor 17m are controlled to obtain the fresh vent door opening XBL. The vent door 17 may be driven.

In order to treat the characteristic shown in FIG. 5 in a mathematical expression, the characteristic curve shown in the first quadrant is approximated by a polygonal line to obtain an estimated value T'vent of the ventilator outlet air temperature.

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

## EQU3 ## Since T'vent = 82 (Fb.XBL + Gb), it can be obtained from the outlet temperature T'vent and the opening degree XBL and the characteristic curve diagram. The calculation coefficients Fb and Gb of the ventilator outlet air temperature are air mix doors. 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, and bG are constants. In order to obtain these constants, the horizontal axis indicates the air mix door opening Xd
sc and Fb and Gb are plotted on the vertical axis. This graph is broken-line approximation 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 bent at the fresh vent door opening X21,
The map data is also divided into two areas. Table 1 is B / L
Fb map data in one mode, Table 2 shows B / L1
8 shows map data of Gb in the mode.

[Table 1]

[Table 2] 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 a memory in the controller 20 in advance.

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

SBL = Tvent−T′vent = Tvent− (Tw−Tint) (Fb · XBL + Gb) −Tint In step 33, the driver 17 is determined according to the deviation SBL.
d and the motor 17m to control the fresh vent door 17
Drive. That is, when the deviation SBL is smaller than -2, the routine proceeds to step 34, the fresh vent door 17 is driven in the closing direction, and when the deviation SBL is larger than 2, the routine proceeds to step 34.
Proceed to 5 to drive the fresh vent door 17 in the opening direction. When the deviation SBL is equal to or more than −2 and equal to or less than 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 bi-level mode of the embodiment. As shown in (a), when the amount of solar radiation suddenly increases at time t1, as shown in (b), the ventilator outlet air temperature decreases, but the foot outlet air temperature does not change. In other words, in the bi-level mode, even if the sun suddenly hits the face of the occupant, the ventilator air temperature is reduced while the air temperature at the feet is kept constant, so that the thermal sensation on the face does not change. Air conditioning of comfortable head cold foot heat is achieved.

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

As described above, 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 Q'sun, and the room temperature set value T'ptc is calculated. Based on the outside air temperature T'a, the amount of solar radiation Q'sun, and the inside air temperature Tinc, the target ventilator outlet air temperature is calculated, and in the bi-level mode in which hot air is blown from the foot outlet 11 while blowing cool air from the ventilator 10. Since the mix door 7 is controlled so as to have the calculated opening degree, and the opening degree XBL of the fresh vent door 17 is controlled based on the calculated target ventilator outlet air temperature.
Fresh vent flow path 16 compared to a conventional vehicle air conditioner
By increasing the flow rate by increasing the size of itself, it is possible to obtain a large temperature difference between the temperature of the air discharged from the foot and the temperature of the air discharged from the ventilator, and the temperature difference becomes variable. Even when the temperature changes, it is possible to supply the ventilator air at the optimum temperature while keeping the foot air temperature constant. Further, a characteristic curve of the ventilator outlet 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 based on the linear approximation curve and the target ventilator outlet air temperature. Since the opening XBL of the seventeen is controlled, the load on the arithmetic processing of the controller 20 is reduced, the arithmetic processing time is shortened, and the responsiveness of the control can be improved. In addition, the air volume from the ventilator is different B
Since different target ventilator outlet air temperatures are set for the / L1 mode and the B / L2 mode,
It is possible to supply an optimal ventilator blowout wind according to the airflow. Furthermore, in the above-described embodiment, an example is shown in which the blower fan 5 and the evaporator 6 are used as the blowing means, but the blowing means may be the blower fan 5 alone.

In the configuration 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 mixing door 7 serves as a first air mixing means.
The door, the fresh vent door 17 is the second door, the room temperature setting unit 21 is the temperature setting unit, the outside air temperature sensor 22 is the outside air temperature detection unit, the inside air temperature sensor 23 is the inside air temperature detection unit, and the insolation sensor 24 is the sunshine. The amount detecting means, the suction temperature sensor 25 constitutes the cool air temperature detecting means, and the microcomputer 20 constitutes the first door opening degree calculating means, the ventilator outlet air temperature calculating means and the control means.

[0023]

As described above, according to the first aspect of the present invention, the first flow path and the second flow path are 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. In addition to calculating the degree of opening of the first door that adjusts the proportion of air flowing through the road, the target ventilator outlet air temperature is calculated based on the vehicle interior temperature set value, the vehicle exterior temperature, the amount of solar radiation, and the vehicle interior temperature. In the bi-level mode in which hot 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 cold air is blown based on the calculated target ventilator blown air temperature. Since the opening degree of the second door for controlling the flow rate is controlled, the flow rate is increased by increasing the fresh vent flow path itself as compared with the conventional vehicle air conditioner, and the foot outlet air temperature and the vent air temperature are increased. In addition to the large difference in temperature from the blast air temperature, the temperature difference is variable and the foot blast air temperature remains constant even when environmental conditions such as solar radiation and outside temperature change in the bi-level mode. Thus, it is possible to supply the ventilated air at the optimum temperature.
According to the second aspect of the present invention, the characteristic curves of the ventilator air temperature with respect to the opening degree of the first door, the temperature of the cool air sent from the cool air blowing means, and the opening degree of the second door are linearly approximated. Since the opening degree of the second door is controlled based on the approximated curve and the target ventilator air temperature, the load on the arithmetic processing of the controller is reduced and the arithmetic processing time is shortened, thereby improving control responsiveness. it can. Furthermore, in the invention of claim 3, different target ventilator outlet air temperatures are set in the first bi-level mode and the second bi-level mode in which the air flow from the ventilator is different, so that an optimal ventilator according to the air flow is set. The blowing wind can be supplied.

[Brief description of the drawings]

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

FIG. 2 is a block diagram showing an electrical configuration of the 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 bilevel mode of the embodiment.

FIG. 7 is a diagram showing a blow-off air temperature characteristic with respect to an air mix door opening degree in the embodiment.

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

[Explanation of symbols]

 DESCRIPTION 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 blowing 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 flow path 17 Fresh vent door 17d Driver 17m Actuator 17s Openness sensor 20 Controller 21 Room temperature setting unit 22 Outside Temperature sensor 23 Temperature sensor 24 Solar radiation sensor 25 Suction temperature sensor 26 Compressor SW1 Main switch SW2 Auto air conditioner switch

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-6-328928 (JP, A) JP-A-5-58145 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B60H 1/00 101 B60H 1/00 102 B60H 1/00 103

Claims (3)

(57) [Claims] 1. A first flow path provided with air heating means, a second flow path bypassing the air heating means, and a cool air sent from the cool air blowing means directly to a ventilator downstream of the cool air blowing means. A third flow path for guiding, wherein 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 a flow rate of cold air by a second door provided in the third flow path; and a temperature setting unit that sets a vehicle interior temperature. Outside air temperature detecting means for detecting the temperature outside the vehicle compartment, inside air temperature degree detecting means for detecting the temperature inside the vehicle, solar radiation amount detecting means for detecting the amount of solar radiation, and the temperature of the cool air sent from the cool air blowing means. Cold air temperature detection hand to detect First door opening 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 unit, the vehicle exterior temperature detected by the outside air temperature detection unit, the solar radiation amount detected by the solar radiation amount detection unit, and the vehicle detected by the indoor air temperature detection unit Based on the room temperature and
A ventilator outlet air temperature calculating means for calculating a target ventilator outlet air temperature; and a bi-level mode in which hot air is blown from the foot outlet while blowing cool air from the ventilator, based on a calculation result of the first door opening degree calculating means. The first
Control means for controlling the degree of opening of the door and controlling the degree of opening of the second door based on the target ventilator air temperature calculated by the ventilator air temperature calculating means. Air conditioner. 2. The vehicle air conditioner according to claim 1, wherein the control unit ventilates the opening of the first door, the cold air temperature detected by the cold air temperature detecting unit, and the opening of the second door. An air conditioner for a vehicle, wherein a characteristic curve of wind temperature is linearly approximated, and an opening degree of the second door is controlled based on the linearly approximated curve and the target ventilator blown air temperature. 3. The vehicle air conditioner according to claim 1, wherein the control unit is configured to set 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. An air conditioner for a vehicle, wherein a ventilated air temperature is set.