JPS6212043B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vehicle internal/external air switching control method and device for controlling internal air circulation and external air introduction in a car air conditioner installed in a vehicle such as an automobile.

Conventionally, this type of switching control is based on simple judgment, such as one that controls whether to switch to outside air intake based on inside air conditions, and another that controls whether to switch to inside air circulation based on outside air conditions. There is something to do.

When air conditioning is controlled by internal air circulation, there is a problem that the air inside the vehicle gradually becomes contaminated, and when air conditioning is controlled by introducing fresh outside air, the cooling capacity may be insufficient in summer, etc.
There is a problem that strong cooling capacity is required.

The present invention has been made in view of the above problems, and by appropriately switching between inside air circulation and outside air introduction,
The first objective is to provide a method for switching between inside and outside air for a vehicle, which can compensate for the lack of air conditioning capacity while preventing air pollution in the vehicle interior, and which is useful for efficient air conditioner control. A second object is to provide a device which automatically and appropriately carries out the method.

The present invention will be described below with reference to embodiments shown in the accompanying drawings. In this embodiment, the present invention is applied to a generally known automobile air conditioner using a cold air/warm air mixing method. An outside air suction port 1a for internal air circulation and an internal air suction port 1b for internal air circulation are formed, and both suction ports are opened and closed by an internal and external air damper 2. Inside the ventilation duct 1, toward the downstream side, there is a blower motor 3, a cooling cycle CC
an evaporator 4 that forms part of the cooling water cycle HC of the engine EG, a heater core 5 that forms a part of the cooling water cycle HC of the engine EG, and a temperature control damper (A/ M dampers) 7 are arranged in order. Upper and lower air outlets 1e and 1d are formed at the most downstream part of the ventilation duct 1 to blow out the temperature-controlled air in the duct to the upper and lower parts of the vehicle interior, and both air outlets are air outlets. It is opened and closed by a damper 8.

The control circuit 10 receives various information signals and executes processing based on preset programs in order to perform temperature control and various operation mode controls, and electrically controls the operation of the functional elements 1 to 8. It is a command.

As means for inputting various information signals to the control circuit 10, an inside temperature sensor 21 including a heat-sensitive resistor that generates an analog voltage signal corresponding to the temperature Tr inside the vehicle interior, and an analog voltage signal corresponding to the temperature Ta outside the vehicle interior are used. an outside temperature sensor 22 including a resulting heat-sensitive resistance;
A temperature setting device 23 that includes a potentiometer that generates an analog voltage signal that corresponds to the set temperature Ts (set position), and an opening sensor 24 that includes a potentiometer that generates an analog voltage signal that corresponds to the opening degree Ar of the temperature control damper 7. , and a switch panel 11 that generates on/off signals by operating a group of switches such as run, stop, and operation mode selection.

In addition, the engine EG is used as a means for operating functional elements according to electrical commands from the control circuit 10.
an electromagnetic clutch 31 for intermittent driving force from to the cooling cycle CC; an electromagnetic valve 32 for opening and closing the cooling water circulation path to the heater core 5 in the heating cycle HC;
and negative pressure actuators 33, 34, 35 controlled by electromagnetic valves that use engine negative pressure to open and close the internal and external air damper 2, temperature control damper 7, and outlet damper 8.
is provided. The display panel 12 displays the operating status of the air conditioner and the control device based on the output signal of the control circuit 10.

The control circuit 10 receives power from the on-vehicle battery 14 when the ignition switch 13 of the vehicle is turned on, and becomes operational.

As shown in FIG. 2, the control circuit 10 includes a digital computer (microcomputer) 10a that performs information processing based on a preset control program, and signal input means 21, 22, 23, 2.
An analog input interface 10b selectively converts the analog voltage signal from the switch panel 11 into an analog-to-digital signal and inputs it to the computer 10a; Ace 10c, an amplifier circuit 10d that amplifies the operation command signals of the functional elements 3, 31 to 35 output from the computer 10a, an information processing clock generation circuit 10e, a constant voltage circuit, and the computer 10c immediately after the ignition switch 13 is turned on. It consists of an initialization circuit (none of which is shown) that starts the operation of 10a.

Next, the operation of the above configuration will be explained with reference to the calculation flowcharts shown in FIGS. 3 and 4, and the characteristic diagrams shown in FIGS. 5 and 6.

FIG. 3 is a calculation flowchart showing the calculation processing of the microcomputer 10a according to the switching control program in the control program.

First, the calculation processing of this microcomputer 10a will be explained. Now, in a car equipped with this device, when the vehicle starts operating, the microcomputer 10a receives a stabilized voltage from the stabilized power supply circuit and enters the operating state for several hundred milliseconds (m
The arithmetic processing of the switching control program is executed at a period of about several milliseconds (sec).

That is, the arithmetic processing of the switching control program is started from the step shown in FIG. 2, and the process proceeds to the various signal input step 101. In this various signal input step 101, digital detection data from various sensors 21 to 24 through the A/D converter 10b and each switch signal from the outside air switch and inside air switch installed on the switch panel 11 are input in sequence. The stored air is stored in the RAM and the register in the CPU, and the process proceeds to step 102 for determining the internal air switch.
In the inside air switch determination step 102, it is determined whether the inside air switch is set or not based on the signals inputted in the various signal input steps 101, and when the inside air switch is set, the determination becomes YES. On the other hand, if the set operation has not been performed, the determination becomes NO and the process proceeds to step 103 for determining the outside air switch. In this outside air switch determination step 103, it is determined whether the outside air switch is set or not in the same manner as described above. When the set operation is performed, the determination becomes YES, and on the other hand, when the set operation is not performed, the determination becomes YES.
If the answer is NO, the process proceeds to step 104 for determining incompetence. In this capacity deficiency determination step 104, the detection data indicating the opening degree of the temperature control damper 7 input and stored in the various signal input step 101 is compared with a set value having a predetermined hysteresis to determine if the margin of cooler capacity becomes zero. If the margin is zero, the determination becomes YES, and if the margin has not reached zero, the determination becomes NO, and the determination of the outside air switch determination step 103 becomes YES. As in the case of getting tired, the process proceeds to outside air command step 105. In this outside air command step 105, the outside air command signal is sent to the switching actuator 3 of the functional element.
3 and the display panel 12, the inside/outside air damper 2 is switched to the outside air side to control the outside air introduction state, and the display panel 12 is made to display that it is now on the outside air side, and the process proceeds to the outstep.

After this outstep, other control system calculations include car air conditioner temperature control, air blow control, and compressor control. After this outstep, calculation processing for other control systems is performed, and then the process returns to the instep, with a cycle of several hundred meters.
It is becoming sec.

On the other hand, when the judgment in the inside air switch judgment step 102 becomes YES, the inside air command step 1
Proceed to 06. In this inside air command step 106, the inside air command signal is applied to the switching actuator 33 and the display panel 12, and the inside/outside air switching damper 2 is switched to the inside air side to control the inside air circulation state.
Indicate that the player has become shy, and then proceed to the outstep.

Further, if the determination in the capacity shortage determination step 104 becomes YES, the process proceeds to a periodic switching routine 200, in which control is performed to alternately switch between internal air circulation and outside air introduction at times corresponding to the outside temperature, inside temperature, and set temperature.

That is, in this periodic switching routine 200, the routine first proceeds to an inside/outside air flag determination step 201 in FIG. The determination becomes NO, and the process proceeds to shyness time calculation step 202. In this inside air time calculation step 202, the inside air time tin at the time of alternating switching is calculated from the set temperature.
The difference between Ts and the outside temperature Tam is determined according to the function f ₁ (T ₁ ) shown in the characteristic diagram of FIG. 5 corresponding to T ₁ = Ts − Tam,
The process advances to the next coefficient calculation step 203. In this coefficient calculation step 203, _{the coefficient C is calculated according to the function f 2 (} T ₂ ) shown in the characteristic diagram of FIG. Proceed to the outside air time calculation step 204 and calculate the outside air time tout.
It is calculated using the calculation formula of tout=C・tin, the inside and outside air flag is set in the inside and outside air flag setting step 205, the timer for alternate switching is reset to zero in the timer reset step 206, and the next timer calculation step is started. Proceed to 207. In this timer calculation step 207, the timer data D up to that point is set to "1".
are integrated (D=D+1). At this time, since one cycle of calculation by the control program is processed at a substantially constant cycle, the timer data D corresponds to the elapsed time when the capacity is insufficient. Subsequently, in a first time determination step 208, it is determined whether the elapsed time according to the timer data D has reached the internal air time tin, and when the determination becomes NO, the process proceeds to an internal air command step 209 to issue an internal air command signal. It is generated and latched in the amplifier circuit 1d, and the inside/outside air damper 2 is switched to the inside air side through the switching actuator 33.

Further, when the determination in the first time elapse determination step 208 becomes YES, the process proceeds to the next second time elapse determination step 210, and the elapsed time according to the timer data D is equal to the sum of the inside air time tin and the outside air time tout. Determine whether (tin + tout) has been reached,
If the judgment is NO, the outside air command step 211
Then, an outside air command signal is generated, the outside air command signal is latched in place of the inside air command signal in the amplifier circuit 1d, and the inside and outside air damper 2 is switched to the outside air side through the functional element switching actuator 33.

Further, when the determination in the second time elapse determination step 210 becomes YES, the process proceeds to an inside/outside air flag release step 212 to cancel the outside air flag.

Next, the overall operation of switching control of the inside/outside air damper 2 in various states will be sequentially explained.

First, by turning on the key switch of the car, a stabilized power supply circuit (not shown) starts operating.
The stabilized voltage is supplied to each circuit including the microcomputer 10a, and the microcomputer 10a is put into operation. Upon this start of operation, the microcomputer 10a initializes the states of its registers, counters, latches, etc., and then starts arithmetic processing of the control program.

If the outside air and inside air switches are not operated at the time of starting calculation by turning on the key switch and there is no shortage of capacity, when the switching control program shown in FIG. Switch judgment step 102, outside air switch judgment step 10
3. When the judgments in the capacity insufficiency judgment step 104 and the like are all negative, an outside air command signal is applied to the switching actuator 33 and the display panel 12 at an outside air command step 105, and the process proceeds to the out step. At this time, the switching actuator 3 is activated by the outside air command signal.
3 controls the switching of the inside/outside air damper 2 to the outside air introducing state, and displays on the display panel 12 that it is now on the outside air side. As a result, one calculation process for the inside/outside air switching control is completed, and thereafter, the same calculation process from the in-step to the out-step described above is repeated at a cycle of several hundred milliseconds to maintain the outside air introduction state. .

During the air conditioner control with outside air being introduced by this repeated calculation, the determination in the capacity deficiency determination step 104 is made because there is no margin for cooling capacity.
The result is YES, and the process proceeds to the periodic switching routine 200. Thereafter, while the capacity is insufficient, the calculation is repeated to proceed through various signal input step 101, inside air switch judgment step 102, outside air switch judgment step 103, and capacity deficiency judgment step 104, and then proceed to the periodic switching routine 200.
By calculating 0, internal air circulation and outside air introduction are alternately switched, and each time the set temperature Ts and outside air temperature are changed.
It is determined appropriately based on Tam and internal temperature Tr to compensate for the lack of capacity and to prevent internal air from becoming contaminated.

That is, when the periodic switching routine 200 is first reached, the process starts from the inside/outside air flag determination step 201 to the inside/outside air time calculation step 20 in FIG.
2. Coefficient calculation step 203, outside air time calculation step 204, outside air flag setting step 20
5. Timer reset step 206, timer calculation step 207, first time elapse determination step 20
8. Execute the calculation to proceed to the inside air command step 209, determine the inside air time tin and the outside air time tout for alternate switching, and first switch the inside and outside air damper 2 to the inside air circulation state.

Thereafter, when the periodic switching routine 200 is reached for the second time, the determination in the inside/outside air flag determination step 201 is reversed to YES, and steps 202 to 206 are performed.
The process directly proceeds to a timer calculation step 207, and then to a first time elapse determination step 208 and an internal air command step 209, thereby maintaining the internal air circulation state. Thereafter, by repeating the same calculation, the timer data D in the timer calculation step 207 is
gradually increases, and when it reaches the shyness time tin calculated in the shyness time calculation step 202, the first
The determination at the time elapse determination step 208 is reversed to YES, and the calculation that proceeds from the second time elapse determination step 210 to the outside air command step 211 is executed, and the inside and outside air damper 2 is switched to the outside air introducing state. Thereafter, the same calculation is repeated, and when the timer data D reaches the time obtained by adding the previously calculated inside air time tin and outside air time tout, the determination in the second time elapse determination step 210 is reversed to YES, and the outside air flag is canceled. Step 2
The calculation proceeding to step 12 is executed to cancel the previously set inside/outside air flag.

Therefore, the above series of calculation operations calculates the internal air time.
Completes one alternation of inside and outside air corresponding to tin and outside air time tout. Thereafter, while the determination in the capacity insufficiency determining step 104 is YES, the series of calculation operations described above is repeated, and the alternating switching between inside and outside air can be controlled periodically. Furthermore, the inside air time tin is determined by the set temperature Ts and the outside temperature Tam at the start of the series of calculation operations, and the outside air time tout is determined by the set temperature Ts, the inside temperature Tr, and the above inside air time tin. Therefore, each time period changes according to changes in the air conditioning state, and it is possible to appropriately control alternate switching between inside and outside air in various states.

On the other hand, when the passenger manually turns on the outside air switch, the judgment becomes YES when the outside air switch judgment step 103 in FIG. Control to the introduced state.

Further, when the occupant turns on the inside air switch manually, the judgment becomes YES when the inside air switch judgment step 102 in FIG. Control in circulation.

In the above embodiment, the inside/outside air damper 2 is used as the switching means, but for example, a dedicated fan may be provided for each of the outside air suction port 1a and the inside air suction port 1b, and each fan may be selectively switched. Other configurations, such as actuators, may be used.

In addition, a microcomputer 1 that executes digital arithmetic processing based on a control program is provided in the control circuit.
Although an example using 0a is shown, it may be constructed using a hardware analog electronic circuit, a digital electronic circuit, or the like.

In addition, although we have shown a device that alternately switches between inside and outside air when the capacity is insufficient, during steady operation, it alternately switches between inside and outside air at regular intervals, and also changes the inside temperature Tr and the outside temperature.
Other controls, such as adjusting the switching duty ratio in accordance with the deviation of Tam, may be performed.

As described above, in the first invention of the present application, internal air circulation and outside air introduction are periodically switched, and this switching time is changed according to the air conditioning condition, so that air pollution in the vehicle interior can be temporarily removed. This is an excellent effect in that it can be prevented by introducing outside air and compensate for the lack of air conditioning capacity by combining the circulation of inside air, saving the air conditioning capacity and being useful for efficient air conditioner control.

Furthermore, the second invention of the present application has the excellent effect that, in addition to the effects of the first invention, it is possible to provide a device that automatically and appropriately switches between inside and outside air.

[Brief explanation of the drawing]

FIG. 1 is an overall configuration diagram showing an embodiment of the present invention;
Fig. 2 is a block diagram showing the configuration of the electric circuit section in Fig. 1, Fig. 3 is a calculation flow chart showing the main part calculation processing of the microcomputer in Fig. 2, and Fig. 4 is a block diagram showing the configuration of the electric circuit section in Fig. 1. A calculation flowchart showing detailed calculation processing of the periodic switching routine, FIG. 5 is a characteristic diagram showing the inside air time, and FIG. 6 is a characteristic diagram showing the coefficient for the outside air time. 1...Ventilation duct, 1a...Outside air intake port, 1b
. . . Inside air suction port, 2 .

Claims (1)

[Claims] 1. In a vehicle interior/exterior air switching control method for controlling switching between internal air circulation and outside air intake in a car air conditioner that controls air conditioning in a vehicle interior, the air conditioning status is detected and the internal air circulation and outside air intake are periodically controlled. A method for controlling internal/external air switching for a vehicle, characterized in that the switching time is changed according to the air conditioning state. 2 Inside air circulation and outside air by the switching means in a car air conditioner that controls the air conditioning inside the vehicle and is equipped with a switching means that selectively opens the inside air intake port that takes in the indoor air of the vehicle and the outside air intake port that takes in the air outside the vehicle. A vehicle interior/exterior air switching control device that controls installation includes a temperature sensor that detects the temperature of each part, and a ratio of inside air time and outside air time that is determined based on the detection signal of the temperature sensor when a predetermined condition of the vehicle interior air conditioning occurs. , a control circuit for alternately applying an inside air command signal and an outside air command signal to the switching means in accordance with each time.