JPH01190522A - Automobile air-condition control device - Google Patents

Abstract

PURPOSE:To compel air to mix with cold air so as to improve the temperature condition of the upper section of the passenger compartment of a vehicle by adjusting the opening degree of an air-mix door so as to limit the capacity of air blow off from a defroster blow-out port when the mode is automatically controlled up to a defroster mode. CONSTITUTION:A means 100 computes a blow-off mode change-over signal in accordance with a thermal load condition of a vehicle. Meanwhile, a detector 25 detects an opening degree of an air-mix door. Further, when the opening degree of an air-mix door is less than a predetermined value, a means 101 determines a blow-off mode including such a mode that air is blown off from a defroster blow-out port. Further, when the opening degree of the air-mix door exceeds the predetermined value, a means 102 determines another mode excepting such a mode that air is blown in an amount exceeding a predetermined value from the defroster blow-out port. Further, a means 103 drives each mode door in accordance with a result of determination of each mode.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to an air conditioner used in a vehicle such as an automobile, and particularly to blowing mode control.

(Prior Art) Examples of automatic control of switching the blowout outlet, so-called automatic control of switching the blowout mode, include Japanese Utility Model Publication No. 54-31704 and Japanese Patent Publication No. 59-19849.

As such an automatic control device, for example, the
In the publication No. 9849, the target blowout air temperature Tt is calculated by assembling room temperature, outside temperature, set temperature, etc. into a predetermined calculation formula. The mode is sequentially switched to vent, pie level, and heat modes from a direction in which the target blowing air temperature Tt is small to a large direction, and the defrost mode is not automatically controlled and is operated manually.

(Problem to be solved by the invention) Since the blowout mode is automatically controlled from vent mode to heat mode, it is necessary to manually switch to defrost mode when the outside temperature is extremely low in winter. Ta.

If the blowout mode is expanded to include a mode in which air is blown out from the defrost outlet, the warm air blown out from the defrost outlet, especially when the air mix door is in the fully open full heat position, has the disadvantage of worsening the upper cabin temperature. .

Therefore, in view of the above-mentioned drawbacks, it is an object of the present invention to prevent the upper temperature in the vehicle interior from deteriorating even when the air blowing mode in which air is blown from the defrost air outlet is selected.

(Means for Solving the Problem) As shown in FIG. 1, the means for solving the problem in the present invention includes a blow-off mode signal calculation means 100 that calculates a blow-off mode switching signal from heat load information of the vehicle, and an air mixer. Air mix door opening degree detector 2 that detects the door opening degree
5, a first blowout mode determination means 101 that determines a blowout mode including at least a mode in which air is blown out from the defrost outlet when the opening degree of the air mix door is determined to be less than a predetermined opening degree; A second blowing mode determining means 102 that determines a blowing mode other than a mode in which a predetermined amount or more of air is blown out from the defrost outlet when the opening degree of the mix door is determined to be a predetermined opening degree or more.
and a driving means 103 for driving each mode door according to the determination results of the first and second blowing mode determining means 101 and 102.

(Function) Therefore, the selection of the mode of blowing air from the defrost outlet, for example the defrost and heat mode, is made when the opening degree of the air mix door becomes smaller than the predetermined opening degree (maximum opening degree and its vicinity). , the air blown out from the defrost outlet is mixed with cold air,
The temperature is also lowered, making it possible to prevent the temperature conditions in the upper part of the vehicle interior from worsening.

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

In FIG. 2, an air conditioning control device for an automobile is shown, and an inside air inlet 2 and an outside air intake 3 are formed in the form of two branches on the most upstream side of an air conditioning duct 1, and an inside/outside air switch is formed at the divided part. A door 4 is provided, and the inside/outside air switching door 4 selects the air to be introduced into the air conditioning duct 1 between inside air and outside air.

The fan 5 is for sucking air into the air conditioning duct 1 and blowing it to the downstream side, and an evaporator 6 and a heater core 7 are arranged on the downstream side of the fan 5.

The evaporator 6 constitutes a cooling cycle together with a compressor (not shown), etc., and is designed to cool the air passing through it.The temperature of the air passing through the evaporator 6 is T.
e is detected by the evaporator outlet temperature sensor 8.

Further, the heater core 7 is inserted into a hot water cycle in which cooling water of an engine (not shown) circulates, for example, and heats the air passing therethrough.

An air mix door 9 is provided in front of the heater core 7, and the air mix door 9 adjusts the ratio of air passing through the heater core 7 to air bypassing the heater core 7 by adjusting its opening degree. be.

Note that the air that has passed through the heater core 7 and the air that has bypassed the heater core 7 meet and mix in an air mix chamber 10 formed on the downstream side of the air conditioning duct 1.

The downstream side of the air conditioning duct 1 is divided into a vent outlet 11, a foot outlet 12, and a defrost outlet 13, which open into the passenger compartment 18, and mode doors 14a, 14 are installed in the separated parts.
b, 14c are provided, and these mode doors 14a, 14
By selecting b and 14c, the blowing mode of the air blown into the vehicle interior 18 can be arbitrarily set.

15 is a bypass duct, one end of which is connected to the air conditioning duct 1 mentioned above.
It opens between the evaporator 6 and the heater core 7, and the other end opens to the vent outlet 11. A cold air bypass door 16 is provided in the bypass duct 15, and the cold air bypass door 16 and the bypass duct 1 are connected to each other.
5 constitutes a cold air bypass unit 17, which bypasses a part of the cold air that has passed through the evaporator 6 to the vent outlet 11 by opening and closing the cold air bypass door 16, and finely adjusts the air temperature blown out. It is now possible to do so.

Reference numerals 21 and 22 are actuators for adjusting the opening degree, which are used to rotate the air mix door 9 and the cold air bypass door 16 described above.

24 is a switching actuator for switching the mode doors 14a, 14b, and 14c described above.

25, 26, and 27 are for obtaining feedback signals, respectively. 25 is an air mix door opening degree that detects the opening degree of the air mix door 9, and 26 is a position detector that detects the opening degree of the cold air bypass door 16. , 27 is mode door 1
This is a position detector that detects the mode positions of 4a to 14c.

28 is a vehicle interior temperature detector that detects the vehicle interior temperature Trd, 29 is a solar radiation sensor that detects the solar radiation amount Ts, 30 is a vehicle interior upper temperature detector that detects the upper part of the vehicle interior (near the head) Tru, and 31 is a vehicle interior temperature detector that detects the vehicle interior temperature Trd. This is an outside air temperature sensor that detects outside air temperature Ta.

32 is a multiplexer, and the various sensors 8.25 mentioned above
- 31 are input, and the input signals are sequentially switched and output according to control signals from a microcomputer 34, which will be described later.

35 is a temperature setting device, and up/down switches 35a, 3
The set can be changed by pressing 5b appropriately.

36 is a mode setting device, at least VE NT (36a
), B I-L (36b), HEAT (36c).

It has a DEF (36d) push button, and when these are pressed, manual control is possible, and the AUTO switch 3
By pressing 7, mode control (VENT, B I
-L, HEAT, DEF/HEAT modes) are automatically controlled according to a predetermined program described below.

38 is a fan switch, FANI (38a)'.

It has push buttons for FAN2 (38b) and FAN3 (38c), and manual control is possible by pressing these buttons. Note that by pressing the AUTO switch 37, the rotation speed can be controlled automatically according to a predetermined pattern.

Reference numeral 39 is a switch for turning on the air conditioner, and when this is pressed, the compressor is operated and the air conditioning is controlled.

40 is an OFF switch for controlling the mode and stopping the fan rotation speed. Temperature setting device 3 like this
5. The signals of the mode setter 36 and fan switch 38 are as follows:
It is input to the microcomputer 34 and used for control.

The microcomputer 34 is a central processing unit (CPU)
, read-only memory (ROM), input/output device (I10
) etc., which are known per se. The microcomputer 34 operates the drive circuit 40 according to a predetermined program based on the input signals from the A/D converter 33, the temperature setting device 35, the mode setting device 36, the fan switch 38, etc. , 41, 42, 43.

Fan 5. Air mix door 9, cold air bypass door 16, mode door 14a-14. c. An example of the control operation of the microcomputer 34, particularly an example of the blowout mode switching operation, is shown as a flowchart in FIG.

That is, in FIG. 3, the microcomputer 34
When the device is started, execution of the program starts from step 200, and in the first step 201°, the above-mentioned signals, the lower cabin temperature Trd, the amount of solar radiation Ts, and the outside air temperature T are
a, Air temperature Te after evaporator blows out, Set temperature Td
, upper cabin temperature (near the head) Tru, engine water temperature T
Sequentially input w and the opening degree θX of the air mix door.

In step 202, a total signal T corresponding to the heat load condition of the vehicle necessary to bring the temperature inside the vehicle interior to the set target temperature is calculated based on data indicating the environmental conditions in the vehicle interior 18.

T = Trd + k x T s + k z Ta
+ k 3 T e- to 4 T d + C... (1
) formula, where 4 for K1- is the gain of each sensor or setting device,
C is a correction term.

Although not described in detail, based on this comprehensive signal T, the rotational speed of the blower and the opening degree of the air mix door are controlled so as to bring the temperature inside the vehicle compartment to a desired set value.

In step 203, a blowout mode switching signal Tf necessary for selecting a blowout mode is calculated based on the above-mentioned input signals of the air temperature Te after blowing out from the evaporator and the opening degree θX of the air mix door.

Tf=Te+, θx=(2) formula However, Ks is the gain of the opening degree of the air mix door.

In the next step 204, the mode setting is automatic (AUTO).
), and if NO, the process proceeds to step 205 of manual mode.

In the case of automatic (AUTO) mode, the next step 20
6, and in step 206 it is determined whether the outside air temperature is higher than a predetermined temperature (15° C. in the temperature increasing direction, 10° C. in the temperature decreasing direction), and if it is higher than the predetermined temperature (B), the process proceeds to step 207. If the temperature is lower than the predetermined temperature (A), the process proceeds to step 208.

In step 207, the vehicle interior upper temperature Te is set to a predetermined temperature (
It is determined whether the temperature is higher than 30° C. in the temperature increasing direction and 25° C. in the temperature decreasing direction. If the temperature is lower than the predetermined temperature (A), the process proceeds to the next step 208.

That is, in step 208, if the outside air temperature Ta is lower than the predetermined temperature (A), and if the vehicle interior upper temperature Tru is lower than the predetermined temperature (A), it is determined whether the blow mode control is completed. .

If the startup control has not been completed (No), the process proceeds to step 209, and if the temperature is below a predetermined temperature using the engine water temperature Tw as a parameter (A), the process proceeds to step 210 to select the defrost mode. If the engine water temperature is higher than the predetermined temperature (B),
The process advances to step 211 where control from defrost mode to heater mode is performed.

If the startup control is completed (YES), the process proceeds to the next step 212, and the opening degree θX of the air mix door 9 input in step 201 is the predetermined opening degree (96% in the opening direction). , 88% in the closing direction), and if the opening degree is smaller than the predetermined opening degree (B), the process proceeds to the next step 213. When the opening degree θX of the air mix door 9 is larger than the predetermined opening degree (A), it is in a full heat state, and in such a case, the following judgment step 2 is performed.
13° 215 is bypassed and the process proceeds to step 217.

Therefore, when the air mix door is fully open or in the vicinity thereof, the mode for blowing out from the defrost outlet is not set, and hot air is prevented from gathering near the head. Note that when the air mix door is closed rather than fully open, that is, when it is mixed with cold air, the temperature has decreased, and in that case, the process proceeds to step 213, and the air is blown out from the defrost outlet as described later. controlled.

In step 213, the blowout mode switching signal Tf necessary for selecting the blowout mode calculated in step 203 is
If the temperature is below a predetermined temperature (A), the process proceeds to step 214, and the defrost and heat mode is set, in which air is blown in 50% portions, for example.

If the temperature is higher than the predetermined temperature (B), step 21
Proceed to step 5.

In step 215, if the blowout mode switching signal Tf is below the predetermined temperature (A), the process proceeds to step 216 and the defrost blowout port is switched from the defrost and heat mode to the
Set to % bleed heat mode. If the temperature is higher than the predetermined temperature (B), the process proceeds to step 219.

In step 219, if the blowout mode switching signal Tf is below the predetermined temperature (A), the process proceeds to step 220, and from the vent mode to the pie level mode (a linear transition is possible).
The mode is set to an appropriate mode up to. If the temperature is higher than the predetermined temperature (B), the process proceeds to step 221 and the vent mode is set.

In addition, in the step 207, if the temperature is higher than the predetermined temperature (B), the step 208, 212°213.2
15 and 217 and proceeds to step 219. That is, under conditions where the outside air temperature Ta is above a predetermined temperature and the upper part of the vehicle interior temperature is above a predetermined temperature, the outside air is relatively warm and the temperature near the head is warm, only the modes excluding the defrost mode and the heat mode are determined. Not possible.

Therefore, under these conditions, only one of the vent mode and pie level mode will be selected, which allows the wind to flow near the head and prevent relatively warm air from accumulating. be.

The flow of determination as described above is returned to the start step 200 via step 221, and the control as described above is performed.

If the blowout mode switching pattern shown in the flow is illustrated, it will be a diagram as shown in FIG. 4.

In addition, in this embodiment, an example is shown in which the blowout mode is automatically controlled to the defrost and heater mode in which approximately 50% of the air is blown out from the defrost outlet in consideration of preventing fogging of the windshield. Of course, a defrost mode can also be added for automatic control.

(Effects of the Invention) As described above, according to the present invention, even when automatically controlling the mode in which air is blown out from the defrost outlet,
By setting a limit on when air is blown out from the defrost outlet by the opening degree of the air mix door, the air blown out from the defrost outlet is limited to when it is mixed with cold air, and the blowout temperature is also reduced. This prevents deterioration of the temperature conditions in the upper part of the vehicle interior.

[Brief explanation of the drawing]

FIG. 1 is a functional block diagram of the present invention, FIG. 2 is a configuration diagram of an embodiment of the present invention, FIG. 3 is a flowchart for controlling the switching of the blowout mode of the present invention, and FIG. 4 is a flowchart of the blowout mode of the present invention. It is a switching diagram. 8...Air temperature detector after evaporator blows out, 14a
, 14b, 14c'' mode door, 25... air mix door opening degree detector, 29... vehicle interior upper temperature detector, 31... outside air temperature detector, 100... mode signal calculation means , 101...first mode determining means, 102...second mode determining means, 103...driving means.

Claims (1)

[Scope of Claims] A blowout mode signal calculating means for calculating a blowout mode switching signal from heat load information of the vehicle; an air mix door opening degree detector for detecting the opening degree of the air mix door; and an air mix door opening degree that is less than a predetermined opening degree. a first blowout mode determination means for determining a blowout mode including at least a mode of blowing air out from a defrost outlet when it is determined that the air mix door is opened to a predetermined opening degree or more; a second blowout mode determining means for determining blowout modes other than a mode in which a predetermined amount or more of air is blown out from the defrost outlet; An air conditioning control device for an automobile, comprising: a drive means for driving a door;