JP2808157B2 - Automotive air conditioning controller - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioning control apparatus for an automobile that controls the temperature of air flowing through a cool air bypass passage by controlling an intake door.

2. Description of the Related Art Conventionally, it has been known that an air conditioning control device for a vehicle uses a cold air bypass unit for controlling (cooling) the temperature of an occupant's head particularly when there is solar radiation. For example, in Japanese Utility Model Publication No. 53-25350, the outlet of the cool air bypass unit is installed separately from the vent outlet and the foot outlet of the main air conditioning duct, for example, toward the head of the occupant, and the other outlets are provided. It is disclosed that the air conditioning feeling can be improved by arbitrarily applying cold air to the occupant's head independently of the air conditioner.

As a system not using the cold air bypass unit, Japanese Patent Laid-Open Publication No. 58-33509 discloses a system in which a ventilation duct is divided into at least two downstream of an air conditioning duct, and an air mixing door is provided in each of the ducts. It is disclosed that conditioned air blown out from a ventilation duct is supplied to different air conditioning zones in a vehicle interior.

(Problems to be Solved by the Invention) However, in the conventional example using the above-described cool air bypass unit, when the outside air temperature becomes low, for example, 0 ° C. or less, the temperature of the air flowing through the cool air bypass passage becomes too low. However, it is directly blown out to the occupant's head, giving a feeling that it is too cold. Also,
In a system in which the air flowing through the cool air bypass passage and the air in the main air conditioning duct are mixed and blown out from the vent outlet, the vent outlet temperature is reduced more than necessary, and the vent outlet temperature is set to a target value based on a comprehensive signal. Has the disadvantage that it cannot be controlled.

Further, in the conventional example in which the above-described cool air bypass unit is not used, control can be performed so that a desired head cool air feeling can be obtained, but the structure and control device of the heater unit are complicated, and the entire device is enlarged. However, there is a problem that the cost is increased as a result.

Therefore, the present invention solves the above-described conventional problems, and controls the temperature of the air flowing through the cool air bypass passage so that an appropriate head cool air feeling can be obtained even when the outside air temperature falls below a predetermined temperature. It is an object of the present invention to provide an air conditioner for a vehicle that has been made possible.

(Means for Solving the Problems) However, the gist of the present invention is that, first,
As shown in FIG. 1, the inside air inlet 3 and the outside air inlet 4 provided upstream of the air-conditioning passage through which temperature-controlled air is blown into the passenger compartment by the temperature control means, and the inside air inlet 3 or the outside air inlet 4 are selectively provided. An intake door 5 that opens and closes, a cool air bypass passage 20 that blows cold air in the air conditioning passage to the upper body of the occupant, a cool air bypass door 21 that controls opening and closing of the cool air bypass passage 20, and an evaporator outlet that detects an evaporator outlet temperature. Temperature detecting means 100, cold air bypass door control instruction determining means 200 for determining whether or not the cool air bypass door 21 is opened, compressor off mode detecting means 300 for detecting a compressor off mode, and opening of the cold air bypass door. The evaporator outlet target temperature calculating means 40 for calculating the evaporator outlet target temperature when the compressor is in the off mode.
0, and an intake door displacement amount calculating means 500 for calculating a displacement amount of the intake door 5 so that the evaporator blowout temperature approaches the evaporator blowout target temperature and outputting the displacement to the intake door driving means 600 for moving the intake door 5. Is to do.

Secondly, in addition to the first aspect of the present invention, a control opening degree regulating means 700 for limiting the intake door displacement calculated by the intake door displacement calculating means 500 so as to maintain at least a predetermined outside air introduction amount is provided. It is in.

(Operation) Therefore, the compressor off mode determining means 300 detects the off mode of the compressor, and furthermore, when the occupant's head feels hot due to solar radiation at low temperatures, the cold air bypass door 21 is opened, This state is determined by the cool air bypass door control instruction determining means 200.

In this case, the displacement (opening) of the intake door 5 is set so that the evaporator outlet temperature detected by the evaporator outlet temperature detector 100 becomes the evaporator outlet target temperature calculated by the evaporator outlet target temperature calculator 400. Is calculated by the intake door displacement amount calculating means 500, and is output to the intake door driving means 600 to move the intake door 5. Thereby, the outside air introduction amount is reduced to a predetermined amount of the inside air circulation amount, and the temperature of the air flowing through the cool air bypass passage can be adjusted.

By adding the control opening degree regulating means, at least the minimum outside air introduction amount is maintained without completely circulating the inside air, and the occurrence of cloudiness on the windshield surface is prevented.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

In FIG. 2, the automotive air conditioning control device includes an intake door switching device 2 provided on the most upstream side of the air conditioning passage 1,
In the intake door switching device 2, an intake door 5 is disposed at a portion where an inside air inlet 3 and an outside air inlet 4 are separated,
The intake door 5 is operated by an actuator 6 so that the air introduced into the air conditioning passage 1 can be selected from inside air and outside air.

The blower 7 sucks air into the air-conditioning passage 1 and blows the air downstream. An evaporator 8 and a heater core 9 are provided behind the blower 7.

The evaporator 8 is connected to a compressor and the like (not shown) by a pipe to form a cooling cycle, and cools the air sucked into the air conditioning passage 1. The heater core 9 circulates cooling water of an engine (not shown) to heat the air. This heater core 9
An air mixing door 10 is provided in front of the air mixing door 10. By adjusting the opening degree θx of the air mixing door 10 by the actuator 11, the amount of air passing through the heat core 9 and air bypassing the heater core 9 is changed. As a result, the temperature of the blown air is controlled.

The opening degree θx of the air mix door 10 is 0% when the position of the air mix door 10 is at the full cool position (I position),
It is 100% at the full heat position (II position).

The downstream end of the air-conditioning passage 1 is divided into a defrost outlet 12, a vent outlet 13, and a heat outlet 14 and opens to the vehicle interior 15, and the divided portions are the mode doors 16, 17, 19.
The mode doors 16, 17, 18 are provided with actuators.
By operating in step 19, a desired blowing mode can be obtained.

Further, this device is provided with a cool air bypass passage 20 that bypasses a part of the air conditioning passage 1. The cold air bypass passage 20 has one end connected downstream of the evaporator 8 of the air conditioning passage 1 and upstream of the air mix door 10, and the other end connected to a position upstream of the upper outlet 13. A part of the passed air can be supplied directly to the upper outlet 13. The amount of cool air supplied through the cool air bypass passage 20 can be adjusted by controlling the opening degree θy of the cool air bypass door 21 by the actuator 22. In addition, cold air bypass door
21 is controlled in its opening degree θy as described later.

Reference numeral 25 denotes a vehicle interior temperature detector that detects a representative temperature Tr in the vehicle interior, and is attached to an instrument panel or the like. In addition, 26 is a head temperature detector attached to the ceiling of the car or the like to detect the temperature Trh around the head, and 27 is the outside air temperature T.
an outside air temperature detector for detecting a; a solar radiation detector for detecting the amount of solar radiation Ts; 29 an evaporator 8 or an evaporator 8
And an evaporating air temperature sensor for detecting the cooling capacity of the air by the evaporator 8 as the temperature of the evaporator 8 or the temperature of the air passing through the evaporator 8. These output signals are selected through a multiplexer (MPX) 31. The signal is converted into a digital signal via the A / D converter 32 and input to the microcomputer 33.

Reference numeral 34 denotes an opening detector that detects the opening θy of the bypass door 21, 35 denotes a position detector that detects the positions of the mode doors 16, 17, and 18, and 36 detects the opening θx of the air mix door 10. Opening detectors, these output signals are also multiplexer
31 and input to the microcomputer 33 via the A / D converter 32, respectively.

Further, output signals from the control panel 37, the temperature setting device 38, and the head temperature setting device 39 are input to the microcomputer 33.

The control panel 37 sets the vent mode to VENT mode,
Mode switches 40a to 40e for manually setting the BI-L mode, HEAT mode, DEF / HEAT mode, and DFF mode, an A / C switch 41 for operating the cooling cycle, and a low (FAN1), medium speed rotation speed of the blower 7 (FAN2), high speed (FAN3)
Fan switches 42a, 42b, 42c, an automatic switch 43 for automatically controlling all of the air conditioning equipment such as a blower, an OFF switch 44 for stopping the driving of the air conditioning equipment, and the positions of the intake door 5 as FRESH (introducing outside air) and REC ( (Internal air circulation).

The temperature setting device 38 includes up-down switches 45a and 45b,
The display unit 46 displays the set temperature Test. The set temperature Tset shown on the display unit 46 can be changed within a predetermined range by operating the up / down switches 45a and 45b. The head temperature setting device 39 has, for example, a dial-type knob 39a, and can change the head setting temperature Thset within a predetermined range set in advance. The temperature setting device 38, the head temperature setting device 39, and the type in which the template bar is slid may be used.

The microcomputer 33 has a central processing unit (CPU), a read-only memory (ROM), a random access memory (RAM), an input / output port (I / O), etc. (not shown). Based on the signals, control signals are output to the actuators 6, 11, 19, 22 and the motor of the blower 7 via drive circuits 48a to 48e, respectively, and each door is
Drive control of 5,10,16,17,18,21 and rotation control of the motor are performed.

Next, a control operation example of the microcomputer 33 will be described.

FIG. 3 shows a flowchart of a main routine of the vehicle air conditioning control device of the present invention. Control is started from step 50, and in step 52, a setting signal input process for inputting a setting operation signal from the control panel 37 and a setting signal from the temperature setting device 38 to the microcomputer 33, and a heat load detection signal, that is, an outside air temperature Each detection signal Ta, Tr, etc. of the detector 27, the vehicle interior temperature detector 25, the head temperature detector 26, the insolation detector 28, the air temperature sensor 29, etc.
A detection signal input process for inputting Trh, Ts, and Te to the microcomputer 33 is performed, and the process proceeds to step 56.

In step 56, calculates in accordance with the overall signal T ₁ corresponding to the heat load of the passenger compartment (1) using the signal input at step 52 and 54 described above.

_{T 1 = K 1 (Tr-} 25) + K 2 (Tad-25) + K 3 Tsc-K 4 (Td-25) + C 1 + C 2 ... (1) where, K ₁ ~K ₄ the calculation coefficient, C ₂ is Operation constant. Tad is a signal obtained by subjecting the outside air temperature Ta detected by the outside air temperature sensor 27 to a predetermined signal delay processing, and Tsc is a solar radiation detector 28.
A predetermined signal processing is applied to the solar radiation amount Ts detected by the above, and the detailed description is omitted here.

Further, C ₁ is determined by the following equation (2).

C ₁ = K ₅ (0−Tad) (2) However, this is applied only when Tad is 0 ° C. or lower, and C ₁ = 0 when Tad is higher than 0 ° C.
Here K ₅ is a calculation factor.

Further, the calculation of the overall signal T ₂ of the air mixing door opening control for the addition of the evaporator air outlet temperature Te to this complex signal T ₁ as a regulator for the following (3) calculated by the formula In addition, the cool air bypass door opening calculating a head overall signal T ₃ for controlling (4) equation.

T ₂ = T ₁ + K ₅ (Te−5) (3) where K ₅ is a calculation coefficient.

T ₃ = K ₆ · Tsc−K ₇ (Thset−25) (4) where K ₆ and K ₇ are operation coefficients, and Tsc is a signal representing the amount of insolation subjected to the above-described signal processing. It is. After this calculation, the process proceeds to step 58.

In step 58, a _TF signal used as a determination value for switching the blowing mode is calculated by the following equation (5).

T _F = Te + K ₈ · θxt (5) where Te is the evaporator outlet temperature, K ₈ is the operation coefficient, θ
xt is the target opening of the air mix door. After performing this calculation, the process proceeds to step 60.

In step 60, according to the result of the overall signal T _1,
As shown in FIG. 4, the air volume of the blower 7 (voltage of the blower)
And the evaporator outlet temperature is controlled.
Proceed to.

In step 62, based on the total signal T ₂ of the operation result of the air mixing door opening control, as shown in FIG. 5, control of the air mix door 10 is carried out, the process proceeds to step 63.

In step 63, as shown in FIG. 6, the switching of the blowing mode is switched to the sixth mode by the _TF signal of the determination value of the switching of the blowing mode.
This is performed as shown in the figure, and the process proceeds to step 62.

In step 64, the control head Overall cool air bypass door 21 by the signal T ₃ and the evaporator outlet temperature is performed as shown in FIG. 8, the process proceeds to step 66.

In step 66, the control of the intake door 5 is performed as a subroutine shown in FIG.

FIG. 8 shows a flowchart of an intake door control routine including a control example of adjusting the temperature of the air flowing through the cool air bypass passage at a low outside air temperature by operating the intake door 5. Control is started from a start step 100. In step 102, an outside air temperature detector 27, an air outlet temperature sensor 29, and an opening degree detector of the air mix door 10 are provided.
A signal input process of inputting a detection signal such as 36 and an operation setting signal of the control panel 37 to the microcomputer 33 is performed. In the next step 104, it is determined whether or not the AUTO switch 43 of the control panel 37 has been pressed, and if YES (pressed), the process proceeds to step 106.
If NO (not pressed), go to step 108.

Here, first, the processing of step 108, in which the intake switch 45 is manually operated when the AUTO switch 42 is not pressed, will be described.

In step 108, it is determined whether the operation of the intake switch 47 is set to REC (inside air circulation). If YES (set), the process proceeds to step 110, where the intake door 5 is set to REC, and the routine is returned. Proceed to step 150.
If NO (not REC), the process proceeds to step 112, and it is determined whether the intake switch 45 is set to FRESH (introducing outside air). If YES (FRESH), the process proceeds to step 114 to take the intake. The door 5 is set to FRESH, and the process proceeds to the return step 150. NO (Intake switch 45
If the operation setting is not performed), the process directly proceeds to the return step 150 and returns to the main routine.

Next, the processing after step 106 when the AUTO switch 43 is pressed in step 104 will be described.

In step 56, it is determined whether or not the DEF switch 40d has been pressed. If YES (the switch has been pressed), the flow proceeds to step 140 to set the intake door 5 to FRESH (introducing outside air).
Proceed to return step 150. If NO (not pressed), go to step 116.

In step 116, it is determined whether or not the compressor is in the OFF mode because the outside air temperature is low, that is, whether or not the temperature of the air flowing through the cold air bias passage is too low, that is, the outside air temperature. YES (OFF mode) Then step 11
If it is NO (ON mode), proceed to step 120.

Next, in step 116, a normal process after step 120, in which the compressor is in the ON mode, that is, the temperature of the air flowing through the cool air bypass passage does not become too low, will be described.

In step 120, it is determined whether or not the vehicle interior set temperature Tset is 18 ° C., and if YES (Tset = 18 is set during maximum cooling), the process proceeds to step 136, where the intake door 5 is set to REC, and the return step 150 Proceed to. If NO (Tset # 18), the process proceeds to step 122.

In step 122, the determination of the outside air temperature Ta is performed.
When the temperature is not higher than 8 ° C., the process proceeds to step 140, the intake door is set to FRESH, and the process proceeds to return step 150. When the outside air temperature Ta is equal to or higher than 23 ° C. (the hysteresis is provided between 18 ° C. and 23 ° C.), the process proceeds to step.

In step 124, the air mixing door opening degree θx is determined. When the opening degree θx is equal to or less than 20 ° C., step 12
6, when the opening θx is equal to or greater than 50 ° (a hysteresis is provided between 20 ° and 50 °), the process proceeds to step 140, and the intake door 5 is set to FRESH. Proceed to return step 150.

In step 126, it is determined whether or not the air volume control of the blower 7 is an automatic control.
If NO (manual), go to step 130.

In step 130, the air volume B _LM of the blower 7 under manual control is compared with B _{LA under} automatic control. If B _LM > B _LA , the routine proceeds to step 132, where the air volume B under manual control is performed.
_{LM is set} to the current air volume (manual air volume B _LM is set to the current air volume B _L ). If B _LM ≦ B _LA , the above step 128
Then, the air volume B _LA by the automatic control is set to the current air volume (the automatic air volume B _LA is set to the current air volume B _L ). After step 128 or step 132,
Proceeding to 134, the size of the current air volume _BL (for example, divided into five levels) is determined. If the air volume _BL is equal to or less than one stage (small air volume), the routine proceeds to step 134, where the intake door 5 is set to the MIX position where REC and FRESH are mixed, and the routine proceeds to step 150. If the air volume _BL is greater than or equal to five levels (large air volume), the routine proceeds to step 136, where the intake door 5 is set to REC, and the routine proceeds to return step 150 to return to the main routine.

If it is determined in step 116 that the compressor is in the OFF mode (YES), the process proceeds to step 118. The step
At 118, it is determined whether or not the cool air bypass door opening is open. If NO, the process proceeds to step 120, and if YES, the process proceeds to step 142.

The processing after step 142 is a processing for controlling the intake door 5 when the temperature of the air passing through the cold air bypass passage is too low, and appropriately increasing the temperature of the air passing through the cold air bypass passage. The door opening θ _IN is displaced from the position of 100% FRESH when the outside air is low to a position on the REC side by a predetermined amount. This displacement amount (intake door target opening θ ′ _IN ) is the evaporator outlet temperature Te (Te is calculated based on the total signals T ₁ and T ₃ , respectively, whichever is smaller) and the total. It is calculated from the method based on the signal T _1.

First, in step 142, the intake door target opening θ ′ _IN is calculated, and the intake door target opening θ ′ _IN is obtained by converting Te ′ to an evaporator blow target temperature,
And the difference between Te and ΔTe (ΔTe = Te′−Te), It shall be calculated from The opening degree of the intake door 5 is a control in a case where the outside air temperature is 180 ° C. or less and the heating is performed when the compressor is in the off mode, so that the intake door 5 is completely FRESH (100%).

In step 144, as shown in FIG. 9, the internal air circulation is restricted, and since the position of at least A% needs to be held and the required minimum amount of external air needs to be introduced, the intake door target opening degree θ ' _It is determined whether or not _IN is larger than the A%, that is, whether or not the opening can be obtained by introducing a predetermined minimum amount of outside air. If YES (θ ′ _IN > A), the process proceeds to step 146;
The intake door opening θ _IN is set to the intake door target opening θ ′ _IN calculated in step 142, and the routine proceeds to return step 150. If NO (θ ′ _IN ≦ A), step 148
Then, the intake door opening θ _IN is set to the aforementioned A% opening, and the routine proceeds to return step 150.

Thus, when the outside air temperature is low, for example,
In the case of the OFF mode (step 116), the intake door 5 is brought closer to REC from the 100% FRESH position to the predetermined limit position (A%) in order to appropriately raise the temperature of the air flowing through the cold air bypass passage (step 116). By performing step 142 and subsequent steps), control is performed so that the cold outside air does not excessively enter the vehicle interior, so that the temperature of the air flowing through the cool air bypass passage is not too cold.

(Effects of the Invention) As described above, according to the present invention, the intake door is displaced by a predetermined amount from the 100% FRESH state to the REC side in the compressor OFF mode in which the outside air temperature is low, for example. The temperature of the air flowing through the cold air bypass passage is raised, which allows the outlet temperature of the vent outlet to rise to a temperature close to the target temperature inside the cabin, preventing the head temperature from becoming too cold and controlling the head temperature to a comfortable state. can do. Further, since the required minimum amount of outside air is ensured, it is possible to minimize the occurrence of fogging of the window glass.

[Brief description of the drawings]

FIG. 1 is a functional block diagram of the present invention, FIG. 2 is a block diagram of an air conditioning control apparatus for a vehicle according to the first embodiment, FIG. 3 is a flowchart showing a main routine of a microcomputer used in the first embodiment, and FIG. graph showing the characteristics of the evaporator outlet target temperature and blower voltage based on _1, Figure 5 is graph showing the characteristics of the air mix door target opening based on the total signal T _2, FIG. 6 is a switching outlet mode graph showing the characteristics of a blow mode based on the determination value T _F, FIG. 7 is graph showing the characteristics of the evaporator outlet target temperature and the cool air bypass door based on the total signal T _3, FIG. 8 is the control of the intake door FIG. 9 is a characteristic diagram of the opening degree of the intake door. 3 ... inside air inlet, 4 ... outside air inlet, 5 ... intake door, 20 ... cold air bypass passage, 21 ... cold air bypass door, 100 ... air blowout temperature detection means, 200 ... cold air bypass door control instruction judgment Means, 300: Compressor off mode detection means, 400: Evaporation target temperature calculation means, 500
... intake door displacement amount calculating means, 600 ... intake door driving means, 700 ... control opening degree regulating means.

Claims (2)

(57) [Claims] 1. An inside air inlet and an outside air inlet provided upstream of an air conditioning passage for blowing temperature-controlled air into a vehicle cabin by a temperature adjusting means, an intake door for selectively opening and closing the inside air inlet or the outside air inlet, A cool air bypass passage for blowing cold air in the air conditioning passage to the upper body of the occupant; a cool air bypass door for controlling opening and closing of the cool air bypass passage; an evaporator outlet temperature detecting means for detecting an evaporator outlet temperature; A cold air bypass door control instruction determining means for determining whether or not the compressor is off; a compressor off mode detecting means for detecting a compressor off mode; and an evaporator outlet for calculating an evaporator outlet target temperature when the cool air bypass door is opened and the compressor is in the off mode. A target temperature calculating means, wherein the evaporator outlet temperature is an evaporator outlet target temperature. Intake displacement amount calculated doors, automotive air conditioning control device characterized by comprising the intake door displacement calculating means for outputting to the intake door driving means for moving the intake door to approach. 2. A control opening restricting means for restricting an intake door displacement calculated by an intake door displacement calculating means so as to maintain at least a predetermined amount of outside air introduced. Automotive air conditioning controller.