JPS62268727A - Air conditioner for automobile - Google Patents

Abstract

PURPOSE:To improve comfortableness, by sensing a level of solar radiation and changing a reference to judge an outside air temperature when operation of a compressor is interrupted in the case that an outside air temperature is less than a prescribed temperature. CONSTITUTION:There are provided an outside air sensor 29 for sensing an outside air temperature and a level of solar radiation judging means 200 for judging a level of solar radiation shining upon a compartment 19. There is also provided an outside air judging means 300 having a plurality of reference values set according to the result of the judgment of the level of solar radiation judging means 200. The outside air judging means 300 compares the reference values set according to the result of the judgment of the level of solar radiation with an output from the outside air sensor 29. A compressor control means 400 controls a compressor 7 according to the result of the judgment of the judging means 300. With the arrangement, the temperature of air blown out is lower as the level of solar radiation is higher, whereby comfortableness of air conditioning is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to an air conditioner for a vehicle, particularly to improving compressor control.

(Prior Art) Since the compressor of a vehicle air conditioner usually uses a driving engine as its drive source, it is desirable to save power and energy by reducing the drive of the compressor as much as possible. In Publication No. 90721, when the outside air temperature is lower than a predetermined value, the compressor is stopped and the outside air is used to maintain the inside temperature at a comfortable temperature. If it is on the cool side, the cooling capacity is insufficient by introducing outside air, so the compressor is driven.

(Problems to be Solved by the Invention) However, in the conventional example described above, no consideration is given to the influence of solar radiation entering the vehicle interior. For example, if the outside air temperature is 18°C, the air temperature on the artificial side of the evaporator will rise by about 5°C due to the exhaust heat from the engine and the heat from the blower, so if the compressor is stopped, the air mix door will be fully cooled. If so, the blowing air temperature will be around 23°C.

This blowing air temperature is comfortable when there is no solar radiation, but
In the presence of sunlight, the occupants were highly disturbed, and unless the temperature of the blown air was lower, they would not experience cold heads or warm feet, causing discomfort and anger to the occupants.

Therefore, the present invention solves the above problems and provides a vehicle air conditioning control III device that can automatically adjust the hot water temperature according to solar radiation and improve comfort while saving power and energy. The challenge is to do so.

(Means for Solving the Problems) As shown in FIG. a solar radiation level determination means 200 for determining the solar radiation level determination means 200; and an outside air determination means for determining the magnitude of the output from the outside air sensor 29, in which a plurality of reference values are set according to the determination results of the solar radiation level determination means 200; 300, and a compressor control means 40 that controls the compressor 7 according to the determination result of the outside air determination means 300.
There is a vehicle air conditioner comprising:

(Function) Therefore, according to the present invention, the solar radiation level determining means 20
If the determination of the level of solar radiation by 0 is different, the reference value of the outside air temperature determination means 300 changes and the compressor 7 is controlled accordingly, so the temperature of the air blown into the vehicle interior also changes accordingly. It is something that can accomplish the task.

(Example) In Fig. 2, the vehicle air conditioner is formed in such a way that an inside air population 2 and an outside air population 3 are divided into two parts on the most upstream side of an air conditioning duct 1, and an inside/outside air switching door is installed in the divided part. 4 is provided, and the air to be introduced into the air conditioning duct 1 is selected by the inside/outside air switching door 4 between inside air and outside air.

The blower 5 is for sucking air into the air conditioning duct 1 and sending it to the downstream side, and an evaporator 6 is provided on the downstream side of the blower 5.

The evaporator 6 is connected to piping together with a compressor 7, a condenser 8, a receiver tank 9, an expansion valve 10, and a pressure control valve 11 to form a refrigeration cycle. The compressor 7 has an electromagnetic clutch 13 for connecting and connecting the driving force transmitted from the engine 12. The pressure control valve 11 controls the evaporation pressure of the evaporator 6 so that the temperature of the evaporator 6 does not drop below the freezing temperature even when the compressor 7 is continuously operated.

An air mix door 14 is provided on the downstream side of the evaporator 6.
and the heater core 15 are arranged, and the air mix door 14
The ratio of air sent to the heater core 15 and air bypassing the heater core 15 is adjusted according to the opening degree of the heater core 15 .

The rear end of the air conditioning duct 1 has a defrost outlet 16 that opens toward the windshield of the vehicle, an upper outlet 17 that opens toward the occupant's face, and a lower outlet that opens toward the occupant's feet in the vehicle interior 19. The air outlet 18 is formed separately, and mode doors 20a, 20b are provided in the separated parts, and the air outlet mode can be changed by selectively opening and closing the mode doors 20a, 2Qb. A mode in which only the upper outlet 17 is opened is called a vent mode, a mode in which both the upper outlet 17 and a lower outlet 18 are opened is called a pie level mode, and a mode in which only the lower outlet 18 is opened is called a heat mode.

The above-described internal/external air switching door 4, air mix door 14, and mode doors 20a, 20b are operated by actuators 21a to 21c, respectively, and the actuators 21a to 21c receive outputs from the microcomputer 23 via drive ports 122a to 22c. Controlled based on signals. In addition, the number of revolutions of the blower is 50 and the electromagnetic clutch is 13.
Similarly, the on/off state is controlled based on output signals from the microcomputer 23 via drive circuits 22d and 22e, respectively.

The microcomputer 23 includes a central processing unit CPU, a read-only memory ROM, and a random access memory RAM.
This is a well-known device that includes a clock generator that generates reference pulses with a crystal oscillator 24, and the like. An A/D converter 25 is connected to the microcomputer 23.

This A/D converter 25 includes an in-vehicle sensor 26 that detects the actual temperature inside the vehicle interior 19, a potentiometer 27 that detects the opening degree of the air mix door 14 (the detected opening degree is assumed to be e), Solar radiation sensor 28 that detects the amount of solar radiation entering the
(The detected amount is assumed to be T.), the outside air temperature is detected by the external air sensor 29 (the detected temperature is assumed to be T1).

), a mode sensor 30 that detects the temperature of the evaporator 6 or the temperature of the air that has passed through the evaporator 6, and a temperature setter 31 that sets the target temperature in the passenger compartment 19 (the set temperature is set to TD
shall be. ) are connected to the microcomputer 2, which converts the analog signals input from these into digital signals.
Send to 3. The microcomputer 23 also includes a fan switch 32 that commands the rotation of the blower 5, and an economy switch 33 that commands the economical operation of the compressor 7.
and an air conditioner switch 34 that commands the drive of the compressor 7. Based on these input signals, the microcomputer 23 calculates control signals to be output to the aforementioned drive circuits 22a to 22e.

Next, an example of the control operation of the microcomputer 23 will be described, but since the difference from the conventional one is only regarding the compressor III, only this example of the compressor control operation will be described, and explanations of other control operation examples will be omitted.

In Fig. 3, the compressor control is first performed in step 1.
At step 00, it is determined whether or not the aforementioned fan switch 32 is on. If it is determined at step 100 that the fan switch 32 is off, the process proceeds to step 109 to stop the compressor. On the other hand, if it is determined that the fan switch 32 is on, the process proceeds to step 101, and based on the output from the outside air sensor 29 mentioned above, the outside air temperature has become smaller than the predetermined value a or larger than the predetermined value a. Determine whether Predetermined value a.

b is, for example, -6°C3-2°C, and is the outside temperature T.

If the value is smaller than the predetermined value a, there is a risk that the compressor will compress the liquid, so in this case, it will be determined as "A" and step 1 will be executed.
Proceed to step 09 and stop the compressor. On the other hand, if it is determined that "B" is larger than the predetermined value, step 10
Proceed to step 2.

In this step 102, it is determined whether or not the above-mentioned economy switch 33 is on, and if the economy switch 33 is off, the process proceeds to step 108.
4 is on. If the economy switch 33 is off, it means that the passenger does not want economical driving, so if the air conditioner switch 34 is off, the process proceeds to step 109 and the compressor is stopped, but if the air conditioner switch 34 is on, then the compressor is stopped. If so, the process advances to step 111 and the compressor is controlled so that the evaporator does not freeze. That is, the pressure control valve 11 described above
If it has, drive the compressor continuously,
If the pressure control valve 11 is not provided, on/off control is performed near the freezing temperature, as shown by the two-dot chain line in FIG.

If it is determined in step 102 that the economy switch 33 is on, the process proceeds to step 103, where it is determined whether the temperature T set by the temperature setting device 31 described above is set to maximum cooling. do. Step 1 if set to maximum cooling
Proceed to step 11 and perform antifreeze control. On the other hand, if the maximum cooling is not set, the process advances to step 104.

In this step 104, the above-mentioned solar radiation sensor 2
Based on the output from 8, it is determined whether the amount of solar radiation T3 has become smaller than a predetermined value C or larger than a predetermined value d. If the amount of solar radiation T is "C" which is smaller than the predetermined value C, there is no solar radiation, and conversely, the solar radiation it'r s
If "D" is larger than the predetermined value d, it means that there is solar radiation.The process of step 104 constitutes the solar radiation level determining means 200 shown in FIG.

In step 104, if the determination is "C", the process proceeds to step 105; if the determination is "D", the process proceeds to step 106. Steps 105 and 106 are for determining whether the output from the outside air sensor 29 described above is larger or smaller than the reference value. In step 105, the outside air temperature T1 is compared with the reference values e and f, and the step 1
At 06, it is compared with reference values g and h. Standard value e, f
.

g and h are set to 10, 15, 16, and 21 degrees Celsius, for example. If the outside air temperature T1 is determined to be "E" smaller than the reference value e in step 105, or if the outside air temperature T1 is determined to be "G" smaller than the reference value g in step 106, step The process proceeds to step 107, and if it is determined in step 105 that the outside air temperature T, is greater than the reference value f, the process proceeds to step 111, where antifreeze control is performed, and in step 106, the outside air temperature T, is determined to be greater than the reference value. If the temperature is determined to be a large "H", the process proceeds to step 110 and the compressor is subjected to variable thermo-control.That is, as shown by the solid line in FIG. The outside air determination means 300 shown in FIG. 1 is configured by steps 105 and 106.

Step 107 is for determining whether there is surplus cooling capacity based on the opening degree θ of the air mix door 14, and when the opening degree e has reached a predetermined value i (for example, full cool), does not have excess cooling capacity, so step 110
Proceed to step 109 to set the compressor to variable thermo-control, and if the opening e is equal to or greater than a predetermined value j (for example, 50%) ("J"), it is possible to cool the passenger compartment with outside air only, so proceed to step 109. This will stop the compressor.

Note that the processing of steps 109 to 111 constitutes the compressor control means 400 shown in FIG.

In the above configuration, assuming that the fan switch 32 and the economy switch 33 are currently on and there is no solar radiation, the determination in step 104 is "C", so the process proceeds to step 106 and the outside air temperature T1 is set to 21° C., for example. If the outside air temperature T is lower than 16°C, for example, and the air mix door 14 is not on the full cool side, the compressor 7 is controlled by the variable thermostat in step 110. The vehicle is stopped, and the vehicle interior 19 is cooled while using outside air, with the temperature of the air blown from the upper air outlet 17 being kept at a limit of about 23°C.

On the other hand, assuming that there is solar radiation, the determination in step 104 is reversed to "D", so the process advances to step 105.
If the outside air temperature T1 is higher than, for example, 15°C, step 1
Since the compressor is controlled so that the temperature of the evaporator 6 becomes 0° C. by the process in step 11, the temperature of the air blown from the upper outlet 17 is lower than that in the case where there is no solar radiation. Further, when the outside air temperature T is lower than, for example, 10° C. and the evaporator 14 is not on the full cool side, the compressor 7 is stopped and outside air is used.

In addition, in general vehicle air conditioners, vent mode,
In the pie level mode, the structure is such that the air blown from the upper outlet 17 is not affected much by the air that has passed through the heater core 15, except when the air mix door 14 is on the full heat side. If the air temperature on the upstream side is low, the temperature of the air blown from the upper outlet 17 can be lowered regardless of the opening degree of the air mix door 14.

In addition, in the pie level mode, the upper air outlet 17 and the lower air outlet 18 where the air temperature on the upstream side of the heater core 15 is low
Since the temperature difference between the air and the air blown out becomes large, in this embodiment, when there is no solar radiation, the temperature difference can be made smaller than when there is solar radiation.

Note that in the above embodiment, the outside air judgment is performed in two stages depending on when there is solar radiation and when there is no solar radiation, but the invention is not limited to this, and the level of solar radiation can be divided into three or more stages. , Correspondingly, the outside air determination may also be performed in three or more stages.

(Effects of the Invention) As described above, according to the present invention, in a vehicle air conditioning control device that stops a compressor when the outside air temperature is below a predetermined value, the level of solar radiation is detected, and the solar radiation level is detected. Since the criterion for determining outside air temperature is changed depending on the level, the higher the level of solar radiation, the lower the temperature of the blown air can be. Furthermore, in the pie level mode, it is possible to reduce the difference in temperature of the air blown from the upper air outlet and the lower air outlet, where the level of solar radiation is low, and from this point of view, comfort can be improved.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram showing the configuration of the present invention, Fig. 2 is a schematic diagram showing an embodiment of the invention, Fig. 3 is a flow chart showing the compressor control routine of the microcomputer used in the above, and Fig. 4 is a schematic diagram showing the configuration of the present invention. FIG. 3 is a diagram showing control characteristics of a compressor. 7... Compressor, 19... Vehicle interior, 29... Outside air sensor, 200... Solar radiation level determination means, 300...
... Outside air determination means, 400 ... Compressor control means. Figure 3

Claims (1)

[Claims] An outside air sensor that detects the outside air temperature, a solar radiation level determining means that determines the level of solar radiation entering the vehicle interior, and a plurality of reference values according to the determination results of the solar radiation level determining means are set, and the reference value and the above-mentioned 1. An air conditioning control device for a vehicle, comprising an outside air determining means for determining the magnitude of an output from an outside air sensor, and a compressor control means for controlling a compressor according to a determination result of the outside air determining means.