JPH03112713A - Air conditioning control device for vehicle - Google Patents

Abstract

PURPOSE:To ensure temperature adjustment function even when outside temperature is extremely low, by controlling an air mixing door based on temperature setting instead of a general signal, upon judging the occurrence of a heating condition causing the loss of the temperature adjustment function. CONSTITUTION:A general signal corresponding to a thermal load in a cabin is operated with a general signal operation means 100, on the basis of outside temperature, cabin temperature and set temperature in the cabin. The opening of an air mixing door 16 is determined with the first opening determination means 110 based on the result of the operation. Furthermore, the opening of the door 16 is determined with the second opening determination means 120 based on the set temperature in the cabin. Also, a judgement signal corresponding to a thermal load in the cabin is operated with a judgement signal operation means 130 based on the outside temperature and cabin temperature. In addition, the output signals from the aforesaid means 110 and 120 are judged and selected with a judgement and selection means 140, depending upon whether the result of the operation with the means 130 is equal to or above a value in the predetermined heating condition. Finally, the air mixing door 16 is actuated with a drive means 150, depending upon the result of the selection.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a vehicle air conditioning control device, and particularly to a device that automatically controls air conditioning conditions according to environmental conditions.

(Prior art) Conventionally, as this type of device, for example,
As shown in Publication No. 849, a means for calculating the necessary temperature of air blown into the vehicle interior based on outside air temperature, vehicle interior temperature, etc., and a control characteristic determined in advance based on the result of this calculation means. It is well known that the air conditioner is equipped with a drive control means for controlling the drive of an air mix door, a blower, etc., and the air conditioning state is automatically controlled according to environmental conditions.

(Problem to be Solved by the Invention) However, in the above conventional example, as the outside temperature decreases, the air mix door opening degree is increased (in the direction of closing the bypass passage more) or the air volume is increased. I am trying to increase the heating level. Further, the set temperature of the temperature setting device is corrected so that it becomes higher as the outside air temperature becomes lower, and this correction value is used to calculate the total signal. This is to compensate for the fact that since the cabin is covered with glass, the influence of outside air radiation is large.

Therefore, if the outside temperature is extremely low (for example, -1
If the target temperature becomes too high (below 5°C) and there is not enough room in the heater capacity, the target temperature will not be reached even if the air mix door is opened to the maximum and the air volume is set to the maximum heating state. state.

In such a situation, even if you raise the set temperature of the temperature setting device, you will not be able to increase the temperature because the heating capacity is at its maximum, and even if you lower the set temperature, it will not work unless the variable range is extremely large. , the target temperature could not be lowered,
As a result, there was an inconvenience that the temperature adjustment function of the temperature setting device was lost.

SUMMARY OF THE INVENTION Therefore, the present invention solves the problems of the prior art and provides a vehicle air conditioning control device that does not lose its temperature control function even when the outside temperature is extremely low.

(Means for Solving the Problems) However, the vehicle air conditioning control device according to the present invention has the following advantages:
As shown in the figure, a total signal calculation means 100 calculates a total signal corresponding to the heat load in the vehicle interior based on at least the outside air temperature, the interior temperature of the vehicle, and the set temperature in the vehicle interior, and the computation of the total signal calculation means 100. First opening degree determining means 110 that determines the opening degree of the air mix door 16 based on the result.
and a second opening degree determining means 120 that determines the opening degree of the air mix door 16 based on the set temperature in the vehicle interior, and assuming that the set temperature in the vehicle interior is the lowest limit value of the temperature setting device, a determination signal calculating means 130 that calculates a determination signal corresponding to the heat load inside the vehicle based on at least the outside air temperature and the vehicle interior temperature; the output signal of the first opening determining means 110; and the second opening. The output signal of the determination means 120 and the calculation result of the judgment signal calculation means 130 are input, and if the calculation result of the judgment signal calculation means 130 is determined to be a value in a predetermined heating state or higher, the second opening degree is determined. Determination means 1
20 output signals are selected and output, and when the calculation result of the determination signal calculation means 130 is determined to be a value below a predetermined heating state, the output signal of the first opening determination means 110 is selected. and a drive means 150 that drives the air mix door 16 based on the output signal of the judgment selection means 140.

(Function) Therefore, the calculation result of the judgment signal calculation means that calculates a signal corresponding to the heat load in the passenger compartment under predetermined conditions including the condition that the set temperature of the temperature setting device is the lower limit value is displayed in the judgment selection means. When it is determined that the heating state is at or near the maximum heating state, instead of the conventional air mix door control based on the general signal, a second control is performed to determine the opening degree of the air mix door according to the set temperature of the temperature setting device. Since the output signal of the opening degree determining means is selected and inputted to the driving means for driving the air mix door, the above object can be achieved.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 2, the vehicle air conditioning control device is provided with an intake door switching device 2 on the most upstream side of an air conditioning duct 1, and this intake door switching device 2 has an internal air population 3 and an outside air population 4.
An inside/outside air switching door 5 is disposed at the separated part, and by operating this inside/outside air switching door 5 with an actuator 6, the air introduced into the air conditioning duct 1 can be selected between inside air and outside air.

The blower 7 sucks air into the air conditioning duct 1 and blows it downstream, and an evaporator 8 and a heater core 9 are provided behind the blower 7.

The evaporator 8 includes a compressor 10 and a capacitor 11.
, liquid tank 12 and expansion valve 13
The compressor 10 is connected to the engine 14 via an electromagnetic clutch 1 to form a cooling cycle.
The electromagnetic clutch 15 is connected via the electromagnetic clutch 15, and is controlled to be turned on and off by turning on and off the electromagnetic clutch 15. Further, the heater core 9 is configured so that cooling water from the engine 14 circulates therethrough to heat the air. An air mix door 16 is provided in front of the heater core 9, and by adjusting the opening degree of the air mix door 16 using an actuator 17, air passing through the heater core 9 and air bypassing the heater core 9 can be separated. The amount is varied so that the temperature of the blown air is controlled.

The downstream side of the air conditioning duct 1 is divided into a defrost outlet 18, a vent outlet 19, and a heat outlet 20, which open into the vehicle interior 21, and mode doors 22a, 22b, and 22c are provided in the divided portions. , this mode door 2
By operating 2a, 22b, and 22c with an actuator 23, a desired blowing mode can be obtained.

And the actuators 6, 17, 23, the blower 7
The electromagnetic clutch 15 of the compressor IO is controlled based on output signals from the microcomputer 25 via drive circuits 24a to 24e, respectively. This microcomputer 25 includes a central processing unit CPU (not shown),
Read-only memory ROM, random access memory RA
The microcomputer 25 is a well-known device having input/output board I10, etc.
A vehicle interior temperature sensor 26 that detects the outside air temperature TA, an outside air temperature sensor 27 that detects the outside air temperature TA, a solar radiation sensor 28 that detects the amount of solar radiation Ts, and the temperature T! of the evaporator 8. (or the temperature of the air passing through the evaporator 80), output signals corresponding to the set temperature T of the temperature setting device 30 that sets the temperature inside the vehicle, and the air mix door described above. Opening degree detector 3 that detects the opening degree of 16
1 is selected via a multiplexer MPX32, converted to a digital signal via an A/D converter 33, and inputted.

Further, an output signal from the operating section 34 is input to the microcomputer 25 . This operation unit 34 has an AUTO switch for selecting an automatic control state (AUTO) as the control state of the air conditioner, a changeover switch for the inside/outside air switching door 5, a switch for manually setting the speed of the blower 7, etc. be.

FIG. 3 shows an example of air conditioning control in the microcomputer 25 described above as a flowchart, and the contents thereof will be explained below with reference to the same figure.

First, the microcomputer 25 starts execution at step 200, proceeds to step 202, inputs signals from the various sensors mentioned above, and proceeds to step 300.

In step 300, a total signal T corresponding to the heat load in the vehicle interior is calculated, for example, according to equation (1) below.

T=TR+ K I Ta+ K zTg+ K 3T
E-K 4T (1+ C+ 0.41) where K, ~
4 is an arithmetic coefficient, and C1 is an arithmetic constant. Also, T.R.
is the vehicle interior temperature, TA is the outside air temperature, T3 is the amount of solar radiation, T is the evaporator temperature, and To is the set temperature.

Next, the process proceeds to step 400, where a determination signal S is calculated according to equation (2) below.

S = T * + K r T A0K z T E
+ Ct... (2) This (2) formula is Kz'''O in the above-mentioned formula (1).

TD=a predetermined value, and in equation (1), 4α+C is replaced by a new calculation constant 02. Here, α is the lower limit of the temperature that can be set by the temperature setting device 30 under normal usage conditions. Compared to equation (1), this equation (2) is in a form that more easily produces the value of the overall signal in a full heat state (a state in which the air mix door 16 closes the bypass passage) or in a state near full heat. It is. Therefore, this value has significance as a criterion, although it is indirect as will be described later.

In step 500, the air mix door opening degree θS corresponding to the value of S described above is calculated. That is, as is well known in devices that perform air conditioning control using the overall signal T, the air mix door opening degree relative to the overall signal T is predetermined as shown in FIG. Although not shown, the rotational speed of the blower, the blowing mode, etc. are determined in the same way.) In this characteristic line, the opening degree when the value of T is the value calculated in step 400 described above is θ.

It is sought as.

After this θ is determined, the process proceeds to step 600 where θ
, is larger than a predetermined value β, e.

is larger than the predetermined value β (YES), even if the temperature setting device 30 is set to the lowest temperature, the air mix door 16
It is assumed that the temperature is at or near the full heat position, and the process proceeds to step 602, where the air mix door control based on the set temperature is performed instead of the air mix door control based on the total signal T.

That is, as shown in FIG. 5, the opening degree of the air mix door 16 is set according to the air mix door opening degree characteristic curve for the temperature set by the predetermined temperature setting device 30. According to the characteristic curve in Figure 5, the set temperature is L.
Below r”C, the air mix door opening degree is 60%.
After that 1. Between ``C'' and 2℃, the opening degree increases in proportion to the increase in the set temperature, and above 12℃, the opening degree is controlled to be 100% (full heat state).Here, Ll+L! As a specific value of, for example, t+=19
°Lz=23 is used.

On the other hand, if it is determined in step 600 that θ3 is smaller than the predetermined value β (NO), the process proceeds to step 604 and performs air mix door control based on the conventional overall signal T, that is, as shown in FIG. The opening degree of the air mix door 16 with respect to the total signal T is set according to the characteristic curve.

After step 602 or 604, the process moves to another control routine via step 606.

(Effects of the Invention) As described above, according to the present invention, when it is determined based on the determination signal calculated under predetermined conditions that the heating state is such that the temperature control function of the temperature setting device is lost, , airmic doorless control is now controlled based on the setting value of the temperature setting device instead of control based on the general signal, so the temperature adjustment function of the temperature setting device can be used even when the outside temperature is extremely low as in the past. There will be no more loss,
Therefore, an air conditioning control state that ignores the occupant's intentions is not continued.

Furthermore, even when used in overseas regions with environmental conditions that cannot be imagined in Japan, the system can sufficiently meet the demands of passengers.

[Brief explanation of drawings]

FIG. 1 is a functional block diagram of a vehicle air conditioning control device according to the present invention, FIG. 2 is a block diagram showing the configuration of the same vehicle air conditioning control device, and FIG. 3 is a functional block diagram of the vehicle air conditioning control device used in the above vehicle air conditioning control device. A flowchart showing a control routine for air mix door control in a microcomputer, Figure 4 is a characteristic line diagram showing the air mix door opening degree with respect to the overall signal, and Figure 5 is a characteristic line diagram showing the air mix door opening degree with respect to the set temperature. be. 16...Air mix door, 17...Actuator, 25...Microcomputer, 30...Temperature setter, 100...Comprehensive signal calculation means, 110...
1st opening degree determining means, 120... second opening degree determining means, 130... judgment signal calculation means, 140... judgment selection means, 150... driving means. Figure 5 0

Claims (1)

[Scope of Claims] Comprehensive signal calculating means for calculating a comprehensive signal corresponding to the heat load inside the vehicle interior based on at least outside air temperature, vehicle interior temperature, and set temperature in the vehicle interior; and a computation result of the comprehensive signal computing means. a first opening determining means for determining the opening of the air mix door based on a set temperature in the vehicle interior; a second opening determining means for determining the opening degree of the air mix door based on a set temperature in the vehicle interior; a determination signal calculation means for calculating a determination signal corresponding to a heat load in the vehicle interior based on at least the outside air temperature and the vehicle interior temperature, assuming that the set temperature is the lowest limit value of the temperature setting device; inputting the output signal of the opening degree determining means, the output signal of the second opening degree determining means, and the calculation result of the judgment signal calculation means, and determining that the calculation result of the judgment signal calculation means is a value at a predetermined heating state or higher; If the output signal of the second opening determining means is selected and outputted, and if the calculation result of the determination signal calculating means is determined to be a value below a predetermined heating state, the first An air conditioning control for a vehicle, comprising: determination selection means for selecting and outputting an output signal of the opening determination means; and driving means for driving the air mix door based on the output signal of the determination selection means. Device.