JPS611525A - Air conditioner for automobile - Google Patents

Abstract

PURPOSE:To make a temperature adjustable range enlargeable, by finding the estimated blowoff temperature from temperature data at the upstream side of a heater core and opening data of an air mix door, while comparing it with the specified blowoff temperature and limiting the door opening to some extent. CONSTITUTION:A temperature operational device 47 inputs temperature TE at the upstream side of a heater core 9 by a temperature detecting device 17 and opening theta of an air mix door 16 by an opening detecting device 33, and finds the estimated blowoff temperature TF from an equation of TF=TE+Ktheta+D with compensation data K and D. And, an opening limit judging device 49 compares the temperature TF with the specified blowoff temperature on the basis of output out of a temperature operating device 47 and judges whether opening of the air mix door 16 is necessary to be limited or not, and according to the judged result, a controlling device 48 controls the opening of the door 16. Therefore, even if blowing temperature varies to some extent, the same blowoff temperature is maintainable all the time, thus a temperature adjustable range is enlargeable.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to an air conditioner for an automobile.

In particular, it relates to the opening degree control of the air mix door.

(Prior Art) The applicant has already disclosed this type of automobile air conditioner in Japanese Patent Application Laid-Open No. 58-22711.

When the air outlet is set to a mode that blows air at least toward the passenger's face, an air mix door is installed to prevent a large amount of warm air from reaching the maximum heating state and blowing a large amount of warm air toward the passenger's face. We are proposing a system that is equipped with a limiting means to limit the degree of opening. However, in the above conventional example, the opening degree of the air mix door is limited only for a constant suction temperature so that the blowout/outlet temperature does not exceed the target temperature, so when the suction temperature changes, However, the above-mentioned blowout temperature also changes and deviates from the target temperature, making it impossible to obtain a sufficient air conditioning function.

(Problem to be solved by the invention) Therefore, the present invention solves the above-mentioned conventional drawbacks caused by restricting the opening of the air mix door only for a constant suction temperature, and allows the air mix door to operate as needed even when the suction temperature changes. The purpose of the present invention is to provide an air conditioner for an automobile that can perform more appropriate air conditioning by restricting the opening degree of the air mix door.

(Means to accomplish the task) This W! The configuration for achieving i is shown in Figure 1,
The temperature calculation means 47 includes a temperature detection means 17 that detects the temperature TE on the upstream side of the heater core, and a temperature detection means 17 that detects the temperature TE on the upstream side of the heater core, and
By inputting the output signal from the opening degree detection means 33 for detecting the opening degree θ of No. 6, the predicted blowing temperature TF is calculated according to, for example, the following equation.

TF = Tt + K e + D ...... (1
) Note that K and D are correction data.

Then, the opening limit determination means 49 controls the mode setting means 26.
The predicted blowout temperature TF is compared with a predetermined blowout temperature based on the output from the temperature calculation means 47, and it is determined whether or not it is necessary to limit the opening degree of the air mix door 16. The control means 48 controls the opening degree of the air mix door 16 based on the output signal of the opening limit determination means 49. Although the temperature Tε on the upstream side of the heater core is detected by the temperature detecting means 17, the temperature setting means for setting the temperature TE to an average fixed value may be replaced with the temperature detecting means.

(Achievement of the problem) Therefore, an expected value of the blowout temperature is calculated from the temperature on the upstream side of the heater core 9 and the opening degree of the air mix door 16, and a predetermined value corresponding to the expected value and the set position of the mode door 23, 24 is calculated. Since the opening degree of the air mix door 16 is limited when the predicted value is below a predetermined value or above a predetermined value by comparing the blow ratio temperature, the opening degree of the air mix door 16 is restricted even if the suction temperature changes. The opening degree is properly restricted, and therefore,
The above-mentioned problems can be achieved.

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

In FIG. 2, the outline of the automotive air conditioner will first be explained.On the most upstream side of the air conditioning case 1 is an intake switching device! 2 is provided, and this intake switching device 2
In this case, an intake door 5 is arranged at a part where the inside air intake 3 and the outside air inlet 4 are separated.

The intake door 5 is operated by an actuator 6 to adjust the ratio of inside air to outside air taken into the air conditioning case 1.

The blower 7 sucks air into the air conditioning case 1 and blows it to the downstream side, and an evaporator 8 and a heater core 9 are provided on the downstream side of the blower 7. Evaporator 8
are compressor 10, capacitor 11. The compressor 1o is connected to the liquid tank 12 and the expansion valve 13 by piping to form a cooling cycle.

It is connected to the engine 14 of the automobile via an electromagnetic clutch 15, and the drive is controlled to be stopped by turning on and off the electromagnetic clutch 15. Also, the heater core 9.

Cooling water for the engine 14 is circulated to heat the air. An air mix door 16 is provided in front of the heater core 9, and further in front of the air mix door 16 is provided a temperature detection means 17 composed of, for example, a temperature sensor, for detecting the temperature of the evaporator 8. The air mix door 16 determines the ratio of air passing through the heater core 9 to air not passing through the heater core 9 by its opening degree θ. F, H, full cool position F,
It is operated up to C.

The rear end of the air conditioning case 1 has a defrost outlet 1.
9. It is divided into a vent outlet 2o and a heat outlet 21 and opens into the vehicle compartment 22, and a mode door 23 is installed in the separated part.
, 24 are provided, and the mode doors 23, 24 are operated by an actuator 25 so that the blowing mode can be switched to vent mode, pie level mode, foot mode or defrost mode.6. This mode switching is
For example, this is performed by a mode setting means 26 constituted by a mode switch or the like provided on a front board in the vehicle compartment 22, and an output signal of the mode switching setting means 26 operates the actuator 25 via a drive circuit (not shown).

The blower 7, electromagnetic clutch 15, actuator 18
are controlled via drive circuits 28a to 28c in accordance with instructions from the control unit 27, respectively. The control unit 27 includes a multiplexer 27a, an A/D
It is composed of a converter 27b and a microcomputer 27e, and the multiplexer 27a receives the vehicle interior temperature Tr from the vehicle interior temperature sensor 29, 2i! Set temperature Td from degree setting device 30, outside temperature T from outside temperature sensor 31
a.

Temperature 7JjTs corresponding to the amount of solar radiation from the solar radiation sensor 32.

Temperature detection means 1 for detecting the temperature on the upstream side of the heater core 9
7, the opening degree θ from the opening detecting means 33 which detects the opening degree of the air mix door 16, such as a potentiometer, and the mode data from the mode setting means 26. Each of the above signals is appropriately selected according to the control signal, and the A/D converter 2
Output to 7b. The A/D converter 127b converts the input signal into a predetermined digital signal and sends it to the microcomputer 27.
e, and the microcomputer 27c outputs this A
Calculations are performed based on the input signal from the /D converter 27b, and the previous v, 9! The blower 7. outputs a control signal to the dynamic circuits 28a to 28c. Electromagnetic clutch 15, air mix door 16
control.

Air mix door 16 of the microcomputer 27c
An example of the control is shown in FIG. 3, and the air mix door control will be explained based on the figure. In addition to externally inputting Ta, opening detection data 0, and mode data from the mode setting means 26, a read-only memory R provided in the microcomputer 27c is used.
D is read out from the correction data stored in the OM, and the process proceeds to the next step 36.

This step 36 is a step of calculating the expected blowing temperature T. The above data T! :, θ, and D as a calculation factor, the expected blowout temperature TF is calculated using the above equation (1). That is, in step 36, the temperature calculation means 4 of FIG.
7 are made up.

Next, the process proceeds to step 37, in which it is determined from the mode data whether the mode doors 23, 24 are set to the VENT mode. If it is determined that it is VENT mode, step 38
Proceed to the predicted blowout temperature TV obtained in step 36 above.
is compared with predetermined data A stored in the read-only memory ROM. This predetermined data A corresponds to the predetermined blowout temperature, and Tp>A, that is, the expected blowout temperature T
If F is determined to be higher than the predetermined blowing temperature A, the process proceeds to step 45, where the operation of the air mix door 16 is stopped and the opening degree is limited as shown in the characteristic diagram (dotted line) in FIG.
To prevent hot air from blowing out from the vent outlet 20. On the other hand, if it is determined that TF>A is not true, the process proceeds to step 40. Further, if it is determined in step 37 that the mode is not VENT mode, the process proceeds to step 39, and the pie level (Bl-L
) mode, and if it is determined that it is the BI-L mode, the process proceeds to step 38 described above; if it is determined that it is not the BI-L mode, the process proceeds to step 42, and the FOO
It is determined whether the mode is T mode or not.

If it is determined in step 42 that the mode is the FOOT mode, the process proceeds to step 41, and if it is determined that the mode is not the FOOT mode, the process proceeds to step 43.

In step 43, the predicted blowout temperature TF' is compared with predetermined data C, and TF<C1, that is.

If it is determined that the expected blowing temperature TF is smaller than the predetermined blowing temperature C, the process proceeds to step 45 described above, and if it is determined that TF<C does not hold, the process proceeds to step 44.

Therefore, in step 45, cold air is prevented from being blown out from the defrost outlet 19. On the other hand, in step 44, normal control of the air mix door 16 is performed. This control uses the microcomputer 27c to control the air mix door 16 as shown in FIG. As shown in the characteristic diagram (solid line), the setting is controlled to a predetermined position between the full heat position and the full cool position, and the specific processing procedure is based on a known method. That is, the control means 48 in FIG. 1 is constructed from steps 44 and 45.

On the other hand, in step 40, it is determined whether or not the mode is the pie level (BI-L) mode. If it is determined to be the BI-L mode, the process proceeds to step 41; and if it is determined that it is not the BI-L mode, the process proceeds to the step 44 described above. Proceed to.

In step 41, the predicted blowout temperature TF is compared with predetermined data B. If it is determined that TF < B, the process proceeds to step 45 described above, and if it is determined that TF is not less than B, the process proceeds to step 44 described above. Go forward, air mix door 1
No. 6 operation stop or normal control is performed. In particular, in step 45, the opening degree of the air mix door 16 is limited, thereby preventing cold air from being blown out from the defrost outlet 19 and the heat outlet 21.

That is, the steps 38, 41, and 43 constitute the relationship limit determining means 49 in FIG.

Finally, the process returns to the main routine in step 46.5 (Effects of the Invention) As described above, according to the present invention, the predicted blowout temperature is determined based on the temperature data on the upstream side of the heater core and the opening degree data of the air mix door. is calculated and compared with the predetermined blowout temperature, if the predicted blowout temperature is above or below a predetermined value, the opening degree of the air mix door is limited, so even if the suction temperature changes, the blowout temperature will always be the same. 1! The hair can be maintained, and the adjustable range of LI degree is wider than before. Furthermore, it has the effect of improving the air conditioning feeling and enriching the air conditioning function.

[Brief explanation of drawings]

Fig. 1 is a block diagram of the present invention, Fig. 2 is a block diagram showing an embodiment of the invention, Fig. 3 is a flow chart showing air mix door control of the microcomputer used in the above embodiment, and Fig. 4 is a block diagram showing an embodiment of the invention. FIG. 3 is a diagram showing control characteristics of air mix door control in the above embodiment. 9... Heater core, 16... Air mix door, 1
7... Temperature detector, 26... Mode setting means, 33
...Opening degree detection means, 47...Temperature calculation means, 48.
. . . Control means, 49 . . . Opening limit determination means. Figure 4 Control signal

Claims (1)

[Claims] temperature detection means or temperature setting means for detecting or setting the temperature on the upstream side of the heater core; opening degree detection means for detecting the opening degree of the air mix door; mode setting means for setting the position of the mode door; temperature calculation means for calculating an expected blowout temperature based on the outputs from the detection means and the opening degree detection means; and limiting the opening degree of the air mix door according to the outputs from the mode setting means and the temperature calculation means. A vehicle for use in an automobile, characterized in that it comprises: an opening limit determining means for determining whether or not it is necessary to Air conditioner.