JPH06115341A - Air conditioner for vehicle - Google Patents

Abstract

PURPOSE:To secure the pleasant state of keeping the head cool and the feet warm in the case of a vehicle air conditioner having a cold air bypass passage. CONSTITUTION:The fuzzy inference of the opening thetac of a cold air bypass door is conducted on the basis of a number of conditions affecting the environment of keeping the head cool and the feet warm, that is, an insolation quantity Qsun, an evaporator blow-out temperature Te, an air mix door opening thetax, a blower control quantity Bv (step 106-108), and the cold air bypass door is driven and controlled so that this opening may be brought on (step 109).

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 having a cold air bypass passage for guiding cold air immediately after passing through an air mix door to a vent outlet.

[0002]

2. Description of the Related Art In a general vehicle air conditioner (automatic air conditioner), an in-vehicle temperature sensor for detecting a representative temperature in the vehicle is arranged at an appropriate place in the vehicle, and the in-vehicle temperature Tr detected by this sensor and an outside air temperature sensor. The outside air temperature Ta detected by the solar radiation sensor and the solar radiation amount Qsun detected by the solar radiation sensor,
The set temperature Tset set by the temperature setter is used to calculate the total signal T corresponding to the heat load inside the vehicle, and the opening of the air mix door is controlled based on the calculated total signal to blow out into the vehicle. In addition to adjusting the temperature, it also controls the blower output to adjust the amount of air blown into the vehicle.

By the way, recently, an air conditioner having a cold air bypass passage for introducing the cool air immediately after passing through the evaporator to the vent outlet has appeared. For example, Jikkou Sho 59-34
No. 497 publication and Japanese Utility Model Publication No. 60-151710 publication,
In order to cool only the temperature of the occupant's head more than usual when the sunlight is strong, a device has been proposed in which the cool air immediately after the evaporator is directly guided to the vent outlet through a cool air bypass passage provided separately from the main duct. There is. Usually, in an air conditioner having a cold air bypass passage of this kind, one end of the bypass passage is communicated immediately after the evaporator, the other end is communicated with the vent outlet, and a door is provided at the bypass passage inlet,
By adjusting the opening of the door, the temperature of the air blown out from the vent outlet is changed auxiliary.

[0004]

By the way, in the conventional air conditioner having the cold air bypass passage, the opening degree of the cold air bypass door is controlled based on a single condition (solar radiation). With the control based only on, it was not always possible to control the temperature of the head cold feet that suits the sensation of the occupant.

In view of the above circumstances, an object of the present invention is to provide a vehicle air conditioner capable of realizing a more comfortable head cold foot heat condition.

[0006]

In order to solve the above problems, the present invention provides a ventilation duct 10 having a vent outlet 22 and a foot outlet 23 at a downstream end, as shown in FIG.
The blower 12 that generates an air flow that blows into the vehicle in the ventilation duct 10, the evaporator 13 that is disposed in the ventilation duct 10, the heater core 15 that is disposed downstream of the evaporator 13, and the air flow after passing through the evaporator 13 are provided. , The flow passing through the heater core 15 and the flow bypassing the heater core 15 are divided, whereby the mixing ratio of the warm air passing through the heater core 15 and the cold air bypassing the heater core 15 is adjusted to adjust the temperature of air blown into the vehicle. An air mix door 14, a cold air bypass passage 40 that guides the cool air immediately after passing through the evaporator 13 before being mixed with the warm air to the vent outlet 22, a cold air bypass door 41 that opens and closes the cold air bypass passage 40, A cold air bypass door drive means 34 for adjusting the opening degree of the cold air bypass door 41, and a vehicle interior temperature sensor 51, Air temperature sensor 52, a solar radiation sensor 5
3. Means 1 for calculating the total signal T corresponding to the heat load in the vehicle based on the output signal of the temperature setter 54, and opening the air mix door for calculating the target opening θx of the air mix door 14 based on the total signal T Degree calculating means 2 and the air mix door 14 so as to converge to the target opening degree of the air mix door
An air mix door drive control means 3 for adjusting the opening degree of
An evaporator for a vehicle air conditioner having means 4 for calculating the control amount Bv of the blower 12 based on the total signal T, and blower drive control means 5 for controlling the blower 12 so that the calculated blower control amount Bv is obtained. Evaporator outlet temperature detecting means 56 for detecting the outlet temperature Te immediately after passing 13, the evaporator outlet temperature Te detected by the means 56, and the solar radiation amount Qsun detected by the solar radiation sensor 53.
, Fuzzy reasoning about the opening degree θc of the cold air bypass door 41 based on the air mixing door opening degree θx calculated by the air mixing door opening degree calculating means 2 and the blower control amount Bv calculated by the blower control amount calculating means 4. And a cold air bypass door control means 7 for inputting a control signal to the cold air bypass door drive means 34 so that the opening degree is calculated by the means 6. It has a feature.

[0007]

In the air conditioner of the present invention, the cold air bypass door opening fuzzy inference means 6 is based on four input conditions, namely the solar radiation amount Qsun, the evaporator outlet temperature Te, the air mix door opening θx, and the blower control amount Bv. Fuzzy calculation is performed on the optimum opening θc of the cold air bypass door 41. That is, in this case, the antecedent parameter (input) of the fuzzy calculation is the solar radiation amount Qsun, the evaporator outlet temperature Te, the air mix door opening θx, and the blower control amount Bv, and the consequent parameter (output) is the cold air bypass door opening. It is set to θc.

The fuzzy inference outputs an inference result in accordance with a fuzzy rule determined based on an empirical rule or the like. The procedure of the method is as follows, for example. However, since there are four antecedent variables here, the first fuzzy calculation is performed with the antecedent variables being the solar radiation amount Qsun and the evaporator outlet temperature Te, and the antecedent variables are the air mix door opening θx and the blower control. 2 of the second fuzzy operation with quantity Bv
One in parallel or one after another, and outputs the final inference result based on the results of both.

In the first fuzzy operation, first, according to each fuzzy rule, the grade of the variable Qsun of the antecedent part (also called the degree of membership to the fuzzy label, or membership value) is calculated by a given membership function.
Then, the grade of another variable Te is obtained, and the minimum value of both grades is taken. This process is called antecedent process. Next, as a consequent process, the output-side membership function is truncated at the above grade, and the trapezoidal output obtained by the trimming is ORed.

Similarly in the second fuzzy operation, first, according to each fuzzy rule, the grade of the variable θx of the antecedent is obtained by the membership function given in advance, and then the grade of the other variable Bv is obtained. Take the minimum grade. Next, the output-side membership function is truncated at the above grade, and the trapezoidal output obtained by the trimming is ORed.

Next, the two fuzzy operation outputs are further logically ORed to obtain the center of gravity of the trapezoidal portions that are superposed, and the position of the center of gravity is taken as the inference result, that is, the final output "cold air bypass door opening θc".

This inference method is disclosed in, for example, Japanese Patent Laid-Open No. 2-927.
This is an application of a method known in Japanese Patent No. 63, etc. Other inference methods may be adopted separately.

In this device, the opening θc of the cold air bypass door is
However, it is determined not only by the amount of solar radiation Qsun, but also by the conditions including the evaporator outlet temperature Te, the air mix door opening θx, and the blower control amount Bv, so the optimum opening is set in accordance with these conditions.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 2 is a diagram showing a specific configuration of the air conditioner of the embodiment. In this air conditioner, the inside air inlet 10A and the outside air inlet 10B are formed in the most upstream part of the main duct (ventilation duct) 10, and the inside air to be introduced into the main duct 10 is controlled by controlling the opening and closing of the intake door 11. The proportion of outside air can be adjusted.

The main duct 10 is provided with a blower 12, an evaporator 13, an air mix door 14, and a heater core 15 in this order as they go downstream. The evaporator 13, together with the compressor 16, the condenser 17, the receiver tank 18 and the expansion valve 19, is pipe-connected to form a refrigeration cycle. The compressor 16 is driven by the force transmitted from the engine, and its drive is controlled by connecting and disconnecting the electromagnetic clutch.

The air mix door 14 is
The ratio of the air passing through the heater core 15 and the air not passing through the heater core 15 is adjusted. And heater core 1
The air that has passed through 5 and the air that has not passed through 5 are mixed on the downstream side of the heater 15 to be temperature-controlled, and are blown out into the vehicle from the air outlet.

The rear end of the main duct 10 has a defrost outlet 21 for blowing air toward the inner surface of the windshield.
And a vent (VENT) outlet 22 that blows air toward the head of the occupant and a foot (FOOT) outlet 23 that blows air toward the feet of the occupant. Mode doors 24, 25, and 26 are provided at the outlets 21, 22, and 23, respectively. The blowing mode can be changed by selectively opening and closing the mode doors 24, 25 and 26.

The vent outlet 22 is further divided into left and right vent outlets 22R and 22L. Then, by opening and closing the air distribution door 27, the air distribution balance from the left and right vent outlets 22R and 22L can be adjusted.

In addition to the main duct 10, this air conditioner is provided with a cold air bypass duct (cold air bypass passage) 40 that bypasses a part of the main duct 10. One end of the cold air bypass duct 40 is the main duct 1
0 is connected to a position downstream of the evaporator 13 and upstream of the air mix door 14, and the other end is connected to a position in front of the air distribution door 27 of the vent outlet 22. Then, a part of the cool air that has passed through the evaporator 13 can be directly guided to the vent outlet 22. A cold air bypass door 41 is provided at the tip opening of the cold air bypass duct 40, and the vent outlet 22 is adjusted by adjusting the opening of the door 41.
You can adjust the amount of cold air to bypass.

The intake door 11, the air mix door 14, the mode doors 24 to 26, the air distribution door 27, and the cold air bypass door 41 described above are respectively provided with an actuator 30 and an actuator 30, respectively.
Opening / closing control is performed by 31, 32, 33, and 34. The actuators 30, 31, 32, 33, 34, the blower fan 12, and the compressor 16 are controlled by the control unit 50.

The control unit 50 includes a drive circuit for driving the actuator and the blower fan, a microcomputer for supplying a control signal to each drive circuit, an A / D converter connected to the microcomputer, and a multiplexer. It includes.

A in the control unit 50
The / D converter includes an in-vehicle temperature sensor 51 that detects a representative temperature in the vehicle interior and an outside air temperature sensor 52 that detects an outside air temperature.
And a solar radiation sensor 53 for detecting the amount of solar radiation entering the vehicle interior,
Temperature setter 5 for setting the representative temperature (average temperature) in the passenger compartment
4, a potentiometer 55 for detecting the opening degree of the air mix door 14, a duct sensor (evaporator outlet temperature detecting means) 56 for detecting the temperature of air blown at the outlet of the evaporator 13, and a temperature around the head of the occupant. The head temperature setting device 57 is connected.

In this embodiment, when the opening θm of the air mix door 14 is "0%" (the position shown by the solid line in FIG. 2), it is full cool, and when it is "100%" (FIG. 2). The position indicated by the chain double-dashed line) is full hot. The opening degree θb of the cold air bypass door 41 is fully closed when “0%” and fully opened when “100%”.

Next, the contents of the air conditioning control performed by the control unit 50 will be described with reference to the flowchart of FIG. In this embodiment, the microcomputer of the control unit performs arithmetic processing according to a predetermined program to cooperate with each actuator, drive circuit, etc., to realize each function realizing means shown in FIG. Total signal calculation means 1, air mix door opening calculation means 2, air mix door drive control means 3,
The blower control amount calculation means 4, the blower drive control means 5, the cold air bypass door opening fuzzy calculation means 6, the cold air bypass door control means 7, etc. are achieved. The main functions of these will be clarified from the following explanation.

When the control routine shown in FIG. 3 starts, first in step 101, detection signals of various sensors are input. Next, at step 102, the vehicle interior temperature Tr detected by the vehicle interior temperature sensor 51, the outside air temperature Ta detected by the outside air temperature sensor 52, the set temperature Tset by the temperature setter 53, and the solar radiation amount Qsun detected by the solar radiation sensor 54. The total signal T corresponding to the heat load in the vehicle is calculated based on the following equation: T = A.Tr + B.Ta + C.Qsun-D.Tset + E. However, A to D are constants, and E is a correction term.

Next, in step 103, the target opening θx of the air mix door 14 is calculated based on the calculated total signal T, and the air mix door 14 is drive-controlled based on the calculated value. Next, in step 104, the control amount (voltage value) Bv of the blower 12 is calculated based on the total signal T, and the blower 12 is drive-controlled by the control amount Bv.

Then, in step 105, the vent (VE
NT) It is determined whether or not the air outlet is open, and if it is open (YES), the process proceeds to steps 106 to 109 to perform cold air bypass door control, and if it is not open (NO), the process of steps 106 to 109 is performed. The cold air bypass door control passes, and the process proceeds to step 110, where controls other than the cold air bypass door control are performed.

When the process proceeds to step 106, the first fuzzy operation is performed here. In the first fuzzy calculation, the antecedent variable is the solar radiation amount Qsun, the evaporator outlet temperature Te, and the consequent variable is the cold air bypass door opening θc. In this fuzzy calculation, nine fuzzy rules shown by a matrix in FIG. 4 are set according to experience or results obtained by experiments. Hereinafter, each code (fuzzy label) has the following meaning.

PL: Large in the positive direction PM: Medium in the positive direction ZR: Almost "0"

As a membership function expressing the above label for each variable, (a), (b) of FIG.
The one shown in (c) is used. The function of (a) is the membership function of the input variable Qsun, the function of (b) is the membership function of the input variable Te, and the function of (c) is the membership function of the output variable θc.

In the fuzzy calculation step 106, the cold air bypass door opening θc is calculated according to the above-mentioned fuzzy rule using the MIN-MAX rule known from Japanese Patent Laid-Open No. 2-92763. The flow of the calculation is as follows. First, the grades of the antecedent variables Qsun and Te are obtained by the input side membership function for each rule, and the minimum value is output. Next, the output side membership function is used to obtain the consequent part output θc from the grade for each rule. Then, the consequent part output obtained for each rule is ORed. Do so far.

Next, in step 107, a second fuzzy operation is performed. In the second fuzzy calculation, the antecedent variable is the air mix door opening θx and the blower control amount Bv, and the antecedent variable is the cold air bypass door θc. In this fuzzy calculation, six fuzzy rules as shown by a matrix in FIG. 6 are set according to the experience obtained by the empirical rule or the experiment as in the above.

Then, as a membership function expressing the above label for each variable, (a), (b),
The one shown in (c) is used. The function of (a) is the membership function of the input variable θx, the function of (b) is the membership function of the input variable Bv, and the function of (c) is the membership function of the output variable θc.

In step 107 of the second fuzzy calculation, the cold air bypass door opening degree θc is calculated for each rule using the MIN-MAX rule in the same manner as the step of the first fuzzy calculation in accordance with the above fuzzy rules. , OR it.

Next, in step 108, the two calculation results θc1 and θ calculated in steps 106 and 107 are calculated.
c2 is further ORed to find its center of gravity, and the position of its center of gravity is taken as the final inference result. Then, in step 109, the cold air bypass door 41 is controlled so as to obtain the inferred opening degree θc, other control is performed in step 110, and the process returns to the first step.

As described above, the opening degree θc of the cold air bypass door 41 is controlled not only by the amount of solar radiation but also by the temperature at which the evaporator blows,
Since it is determined based on a number of factors such as the air mix door opening degree and the blower control amount (air amount), it is possible to perform more appropriate cold air bypass door control than before. Further, since this calculation is performed based on the fuzzy rule, it can be realized without requiring a complicated control logic, and a passenger can be provided with a comfortable air conditioning environment with a cold head and foot heat.

[0037]

As described above, according to the vehicle air conditioner of the present invention, the cold air bypass door door is controlled based on the amount of solar radiation, the evaporator outlet temperature, the air mix door opening, and the blower control amount. More appropriate cold air bypass door control is possible and a comfortable feeling of head cold foot heat can be secured.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of the present invention.

FIG. 2 is a block diagram showing a schematic configuration of an embodiment of the present invention.

FIG. 3 is a flowchart showing a control operation of the embodiment.

FIG. 4 is a table showing a rule of a first fuzzy operation in the above control.

FIG. 5 shows a membership function used in the first fuzzy operation, where (a) is the membership function of the antecedent variable Qsun, (b) is the membership function of the antecedent variable Te, and (c) is It is a membership function of the consequent part variable θc.

FIG. 6 is a table showing rules of a second fuzzy operation in the above control.

7A and 7B show membership functions used in the second fuzzy operation, where FIG. 7A is a membership function of the antecedent variable θx, FIG. 7B is a membership function of the antecedent variable Bv, and FIG. It is a membership function of the consequent part variable θc.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 General signal calculation means 2 Air mix door target opening calculation means 3 Air mix door drive control means 4 Blower control amount calculation means 5 Blower drive control means 6 Cold air bypass door opening fuzzy calculation means 7 Cold air bypass door control means 10 Ventilation duct 13 Evaporator 14 Air mix door 15 Heater core 22 Vent outlet 23 Foot outlet 40 Cold air bypass passage (Duct) 41 Cold air bypass door 50 Control unit 51 Vehicle temperature sensor 52 Outside air temperature sensor 53 Solar radiation sensor 54 Temperature setter 56 Evaporator outlet temperature detection Means (duct sensor)

[Procedure amendment]

[Submission date] April 7, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Brief description of the drawing

[Correction method] Change

[Correction content]

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of the present invention.

FIG. 2 is a block diagram showing a schematic configuration of an embodiment of the present invention.

FIG. 3 is a flowchart showing a control operation of the embodiment.

FIG. 4 is a chart showing a rule of a first fuzzy operation in the above control.

FIG. 5 shows a membership function used in the first fuzzy operation, where (a) is the membership function of the antecedent variable Qsun, (b) is the membership function of the antecedent variable Te, and (c) is It is a membership function of the consequent part variable θc.

FIG. 6 is a chart showing a rule of a second fuzzy operation in the above control.

7A and 7B show membership functions used in the second fuzzy operation, where FIG. 7A is a membership function of the antecedent variable θx, FIG. 7B is a membership function of the antecedent variable Bv, and FIG. It is a membership function of the consequent part variable θc.

[Explanation of Codes] 1 Comprehensive signal calculation means 2 Air mix door target opening calculation means 3 Air mix door drive control means 4 Blower control amount calculation means 5 Blower drive control means 6 Cold air bypass door opening fuzzy calculation means 7 Cold air bypass door Control means 10 Ventilation duct 13 Evaporator 14 Air mix door 15 Heater core 22 Vent outlet 23 Foot outlet 40 Cold air bypass passage (duct) 41 Cold air bypass door 50 Control unit 51 Vehicle temperature sensor 52 Outside air temperature sensor 53 Solar radiation sensor 54 Temperature setter 56 Evaporator outlet temperature detection means (duct sensor)

Claims (1)

[Claims] 1. A ventilation duct having a vent outlet and a foot outlet at a downstream end, a blower for generating an air flow blown into the vehicle in the ventilation duct, an evaporator arranged in the ventilation duct, and a downstream side of the evaporator. The air flow after passing through the heater core and the evaporator is divided into a flow passing through the heater core and a flow bypassing the heater core, thereby adjusting the mixing ratio of the warm air passing through the heater core and the cold air bypassing the heater core. And an air mix door for adjusting the temperature of air blown into the vehicle, a cool air bypass passage for guiding the cool air immediately after passing through the evaporator before being mixed with the warm air to the vent outlet, and a cold air bypass for opening and closing the cold air bypass passage. A door, a cold air bypass door drive means for adjusting the opening degree of the cold air bypass door, a vehicle interior temperature sensor, an outside air Degree sensor, solar radiation sensor, means to calculate the total signal corresponding to the heat load inside the vehicle based on the output signal of the temperature setting device, and air mix door opening calculation to calculate the target opening of the air mix door based on the total signal Means, an air mix door drive control means for adjusting the opening degree of the air mix door so as to converge to the target opening degree of the air mix door, a means for calculating a control amount of the blower based on the comprehensive signal, and a calculated blower In a vehicle air conditioner having a blower drive control means for controlling the blower to a controlled amount, an evaporator outlet temperature detecting means for detecting the outlet temperature immediately after passing through the evaporator, and an evaporator outlet temperature detected by the means. And the amount of solar radiation detected by the solar radiation sensor, the air mix door opening calculated by the air mix door opening calculating means, A cold air bypass door opening fuzzy calculation means for fuzzy inferring the opening degree of the cold air bypass door based on the blower control quantity calculated by the lower control amount calculation means, and a control signal for controlling the opening degree calculated by the means. A cold air bypass door control means for inputting to the cold air bypass door drive means, and a vehicle air conditioner.