JPS60100750A - Air contamination detecting method of air conditioning controller for vehicle - Google Patents

Abstract

PURPOSE:To judge the contamination in a vehicle room similarly to a human way of sensing and perform effective air conditioning control conforming with the feeling of human beings by judging that a contamination state is entered on the basis of variation in the variation rate of a sensor output signal only when the sensor output signal exceeds a contamination detection threshold value level. CONSTITUTION:A gas sensor 3 outputs an analog signal of a voltage, etc., corresponding to the degree of the contamination in the vehicle room and the sensor output increases gradually as the degree of the contamination increases gradually. The threshold level (b) for air contamination detection is a fixed value larger than the sensor output (a) and varies at a fixed variation rate following up the sensor output. A variation range having at least an upper limit is set as to variation in output (a), and the threshold level (b) is varied within this variation range at an optionally determined variation rate following up the output (a). When the variation of the output (a) is slow, the variation in the threshold level (b) varies following up the variation of the sensor output while the fixed value larger than the output (a), and it is judged that the air in the vehicle room is clean. When the output (a) varies so abruptly that the threshold level (b) can not follow up the variation and the sensor output exceeds the threshold level, it is judged than the air in the vehicle room is contaminated.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an air pollution detection method for a vehicle air conditioning control/device that detects air pollution in accordance with human olfactory characteristics.

Conventionally, it is known that vehicles are equipped with automatic air conditioning control devices. Automatic air conditioning control equipment for vehicles has gas sensors installed inside and outside the vehicle cabin to sense the degree of contamination inside and outside the vehicle interior, and then processes this data using a computer to control the operation of the pump and propeller motors. It operates to appropriately select the state of outside air introduction, ventilation, or inside air circulation.

Specifically, for example, if the degree of pollution inside the vehicle increases, it is necessary to introduce clean outside air into the vehicle, and if the degree of pollution within the vehicle interior decreases, it is necessary to circulate inside air.

However, when actually attempting to automatically operate the vehicle air conditioning control device based on the degree of contamination of the air inside and outside the vehicle interior, the following problem arises.

In other words, for example, if the air inside the vehicle is dirty and the air outside the vehicle is clean, the system will operate to provide ventilation, but whether the air inside the vehicle is dirty or not depends on the occupant's sense of smell. This means that it is difficult to accurately determine whether something is contaminated or not using a gas sensor that simply detects the magnitude of a physical quantity.

In other words, it is difficult to make a driver use the same sense as a human to make the decision to replace the dirty air inside the vehicle with clean air from outside.

In view of the above-mentioned problems, the inventors have created the present invention to effectively solve the problems.

An object of the present invention is to match the method of detecting the degree of contamination inside and outside the vehicle interior to the human olfactory characteristics in a vehicle air conditioning control system, thereby making judgments regarding contamination inside the vehicle interior consistent with the human sense of smell. Similarly, the aim is to enable effective air conditioning control that matches the human feeling.

The present invention is characterized in that, in a vehicle air conditioning control device,
A pollution detection threshold level is set based on the output signal of the air pollution sensor, and a change range having at least an upper limit is set for the change in the sensor output signal, and the pollution detection threshold level is set arbitrarily within the change range. The sensor output signal is changed to follow the sensor output signal at a rate of change determined by 4, and the contamination state is detected only when the sensor output signal exceeds the contamination detection threshold level based on the change in the rate of change of the sensor output signal. The reason is that I decided to judge that there is a problem.

Embodiments of the present invention will be described below based on the accompanying drawings.

First, the principle of the air pollution detection method according to the present invention will be outlined. An object of the present invention is to provide an automatic air conditioning control system for a vehicle that has standards for determining contamination that are similar to human feelings. In order to realize such an air conditioning control device, we will focus on the following pollution conditions and human olfactory characteristics.

(1) The concentration of exhaust gas inside and outside the vehicle, the amount of cigarette smoke, etc. change relatively rapidly.

(2) The human sense of smell cannot detect air pollution that changes slowly and rapidly.

As your sense of smell gradually adapts, you no longer find it unpleasant. That is, there is a range within which the human sense of smell can become accustomed to smells under certain temperature and humidity conditions.

(3) With respect to the above-mentioned range that one can get used to, there is a range above the upper limit where the odor is always felt as unpleasant, and a range below the lower limit where the odor is not felt.

Therefore, considering properties (1) and (2) above, a slow change in sensor output that cannot be detected by the human sense of smell is not judged to be "contaminated," but a rapid change that is detected by the human sense of smell. Contamination detection is carried out based on the principle that only when a change in sensor output is determined to be ``contamination''.

Further, in consideration of the above properties (2) and (3), the above detection method is performed only within a certain range that has an upper limit and a lower limit that can be used.

Next, a description will be given based on a specific example. FIG. 1 shows a block diagram of an air conditioning control device. 1 is a computer forming a control circuit. On the input side of the computer 1, an outside air gas sensor 2 mainly for detecting exhaust gas and an inside air gas sensor 3 mainly for detecting cigarette smoke are provided, and the sensing output of the gas sensor 2. This is input to the computer 1ζ. Output of computer 1 (
tllll includes, as controlled objects, a blower 6 in a duct 5 that forms an air flow path arranged in the automobile, and a blower 6 in the duct 5,
A switching damper 9 is provided at the confluence of the outside air intake duct 7 and the inside air intake duct 8, which are formed in a bifurcated shape on the upstream side of the The actuator 10 is configured so that a drive control signal is output from the computer 1 via a turbine drive circuit 11 and a blower drive circuit 12, respectively.

According to the above configuration, the computer 1 performs the necessary signal processing based on the pollution information from the gas sensors 2 and 3, and the output control signal causes the blower 6 to operate as appropriate to prevent pollution inside and outside the vehicle. Depending on the situation, air conditioning controls such as outside air intake, ventilation, and inside air circulation are automatically performed. In the above signal processing, it is determined whether or not the air inside and outside the vehicle is contaminated based on the sensing output of the gas sensor 2.3, thereby implementing the air pollution detection method according to the present invention.

Next, the output characteristics of the gas sensor 2.3 and the air pollution detection method will be explained. The gas sensor 3 for internal air will be described below as an example.

FIG. 2 shows an example of a change in the output of the gas sensor 3 over time. The output of the gas sensor 3 outputs an analog signal such as voltage 1 according to the degree of pollution in the vehicle interior, and in this case, as the degree of pollution gradually increases, the sensor output 3 gradually increases in proportion to the degree. . On the other hand, for such a sensor output a, there is a threshold level b for detecting air pollution that is larger than the sensor output by a certain value and changes at a constant rate of change to follow the sensor output when it changes. is set. This threshold level b is created in the computer 1, and is made to vary as described above only between the two predetermined limit values a1 and a lower limit a2. Then, when the sensor output a is below the lower limit value a2 or above the upper limit value, the threshold level a is set to a constant value so as to take the lower limit value a2 or the upper limit value a1. .

Here, the meaning of setting the upper limit value a1 and the lower limit value a2 and how to set them will be explained based on FIG. In Figure 3,
The horizontal axis is temperature and humidity, the vertical axis is sensor output voltage, and a3
indicates the limit line above which the user will feel unpleasant at any higher contamination concentration, and the environmental standard value is usually adopted, while a4 indicates the limit line below which the odor will not be felt at a lower contaminant concentration.

The range C defined by the limit lines a3 and a4 is the range in which the human sense of smell can adapt and get used to air pollution.

In the above, when the sensor output is above the limit line 83, it can be determined that the air is polluted regardless of the change state of the sensor output, while on the other hand, when the sensor output is below the limit line a4, the sensor output is It can be determined that the air is clean regardless of the state of change. Further, in range C in which the user can get used to it, it becomes necessary to judge the state of air pollution according to the changing state of the sensor output.

From the above, the sensor output voltage a3 in the normal temperature range e corresponding to the environmental standard value air pollution concentration is taken as the upper limit a1 of the follow-up change range d of the threshold level b,
On the other hand, the lower limit value a2 includes a normal temperature range e that corresponds to the air pollution concentration that cannot be detected by the human sense of smell unless it changes to this extent.
Take the sensor power voltage a4 at . Then, the intermediate range C, in which the user can get used to it, is set as the follow-up change range d of the threshold level b.

However, as is clear from FIG. 3, the above-mentioned range C in which the user can get used to it fluctuates due to the influence of temperature and humidity. Therefore, within this range cl that the user can get used to, the follow-up change range d is set to the lowest level of the sensor output voltage within the normal temperature e. By doing so, it is possible to achieve at least the purpose of always determining that air pollution is contaminated when it exceeds the environmental standard value.

Furthermore, as shown in Fig. 4, the characteristic 1 of the output voltage of the sensor is
3 may have a steep slope due to the influence of temperature and humidity. In such cases, it is necessary to cancel the slope using a temperature compensation thermistor and correct it to approximate the characteristics shown in Figure 3. be.

Therefore, regarding the change in the sensor output a in the follow-up change range d of the threshold level b, which is a range that can be used to, which is set by the lower limit value a2 and the upper limit value a1, if the change is slow, the threshold value The change in level b also follows the change in the sensor output by a certain value larger than the sensor output a, and in this case, the sensor output does not exceed the threshold direct level, so the cabin air is It is judged to be clean. On the other hand, if the sensor output a suddenly changes and the change in the threshold level b cannot follow this change,
Since the sensor output exceeds the threshold level, it is determined that the air inside the vehicle is contaminated. This judgment method is similar to the olfactory characteristics of humans. When the sensor output a changes above the upper limit value 81, the threshold level b becomes a certain upper limit value a1, so it is determined that it is always contaminated, and when the sensor output a changes below the lower limit value a2.
changes, the threshold level b becomes a constant lower limit value a
2, so it is always judged to be clean.

The tracking change range d is divided into, for example, 115 steps,
When the sensor output a changes slowly in the range d, the threshold level b is set to follow the sensor output aζ by ensuring a certain detection margin f of, for example, 25 steps. Therefore, inside the computer 1, calculation processing is performed to change the threshold level b while checking changes in the sensor output a of the gas sensor 3.

In the above example, gas sensor 3 detects the degree of pollution of the air inside the vehicle.
However, the same applies to the air pollution detection method related to the gas sensor 2 that detects the degree of pollution of the air outside the vehicle.

As described above, it is determined whether the air inside and outside the vehicle is clean or dirty, and based on the determination whether the air is clean or dirty inside or outside the vehicle interior, either outside air introduction, ventilation, or inside air circulation in the air conditioner is selected. will be done.

FIG. 5 is a flowchart relating to the above-mentioned ft air conditioning control executed within the computer 1. In the air conditioning control device according to the present invention, in process 14, the pollution state of the inside air and outside air in the vehicle is determined by the above-described detection method, and in process 15
There is a main routine A that outputs the contents of the output memory that stores the control mode in the output memory and executes the necessary control corresponding to the contents of the output memory, a subroutine B that changes the threshold level, The control program includes a subroutine D for setting a predetermined delay time depending on how the state of air pollution changes. The main routine A is repeatedly executed, for example, every 0.2 seconds, and based on the decision 16, the subroutine B is activated every 15 seconds, for example, to check the threshold level. Further, subroutine D for setting the delay time is configured to be executed only when the determination of the pollution state is different between the previous state and the off state as a result of the process 14 related to the determination of the inside and outside air pollution state ( Judgment 17).

In the main routine A, first, in initial setting 18, after the output of the sensor becomes stable, an initial threshold value is set and a threshold change timer is set.

The threshold value change timer is set to, for example, 15 seconds, and the threshold level is then checked and changed every 15 seconds in subroutine B in response to changes in the sensor output signal as described above. Next, in process 19, the outputs of the sensors 2 and 3 are read, and in process 20, the data related to the sensor outputs are integrated. Thereafter, if the process does not proceed to subroutine B, the degree of contamination of inside air and outside air is immediately determined separately based on the air contamination detection method described above, and a control mode is selected based on this (process 14). Combinations of contamination states of inside air and outside air and control modes correspond as shown in the following table.

The control mode determined as described above is stored in the volcanic force memo. and a control mode for the contents of the output memory;
If the control mode of the contents of the volcano memory is equal,
In process 15, the contents of the output memory are output, and the damper 9 and proar 6 are controlled.

Subroutine B for changing threshold level b is as follows:
Data integration (process 20) is performed after 15 seconds (decision 16). First, the average value of the sensor output signal for 15 seconds is determined by the following equation.

Then, take the difference between the above average value and the threshold value at that time,
When the difference is smaller than the detection margin f, the threshold level is raised by, for example, one step (process 21), when it is equal to the detection margin f, the current level is maintained (process 22), and when it is larger than the detection margin f, the threshold level is increased (process 22). For example, lowering the value level by one step (processing 23),
The threshold level b is changed. The amount by which the threshold value is changed is not limited to one step as described above, but can be set arbitrarily. However, this rate of change is determined to be constant. Thereafter, it is determined whether or not the changed threshold level b is within the range d (24), and if it is within the range d, the process directly proceeds to process 25 to reset the threshold value change timer and If it is outside the range, the upper limit value a1 or the lower limit value a2 is set as the threshold value (step 26), and then the threshold value change timer is reset. In this way, the threshold level b is checked every 15 seconds, and by executing subroutine B, the threshold level b changes at a constant rate of change in the sensor output signal a within the range d as described above. It follows and changes, and outside the range a, it is set to the upper limit value a1 or the lower limit value a2.

Therefore, in FIG. 2, if the sensor output a changes slowly, the threshold level b can be followed while maintaining the detection margin f (area F
, H), if the sensor output a changes rapidly, it cannot be followed immediately (area G). As a result, area F,
In area H, the air is determined to be clean, and in area G, the sensor output a exceeds the threshold level b, and the air is determined to be dirty. In addition, in area work, it is always determined to be dirty, and in principle, area E is determined to be clean, but if the sensor output a rises to fall within the range d as shown in the figure, it is determined to be dirty. Next, regarding subroutine D for setting the delay time, if the determination of the contamination state regarding the inside air and outside air determined in process 14 is different from the contamination state in the previous determination, , it becomes necessary to take a control mode corresponding to a new contamination state, but a certain delay time is set before executing the new control mode. Specific examples (some of them) are shown in the table below.

Therefore, according to the above table, if the judgment of the contamination status of inside air and outside air is different, the control mode is determined for the new judgment, but the control mode is determined according to the way the previous state changes from the previous state to the off state. A delay time N is set in a delay timer T. Such a program is executed in subroutine D. After the delay time N is set in the delay timer T,
The main routine is repeated, during which the delay timer T is
The contents of the volcano memory are transferred to the contents of the emerging memory, and a new control mode is then executed in process 15 (decision 27.28, process 29.30). However, if a new contamination state is determined again during the execution of the above main routine, judgment 17
Subroutine D is executed via , a control mode corresponding to the new contamination state is determined, and a delay time N corresponding to the manner in which the contamination state changes is set in the timer memory again.

The reason for setting the delay time as described above is to provide time for confirming that the determination made in process 14 is reliable.

As is clear from the above embodiments, the present invention detects the pollution state of the air inside and outside the vehicle interior, and automatically controls the air conditioner in accordance with the pollution state.
), (3) principles were adopted, making it possible to detect contamination with the same feeling as a human.

As is clear from the above explanation, according to the present invention, the contamination detection threshold level is less affected by direct fluctuations and is close to the human olfactory feeling. It has become possible to obtain contamination judgments and improve the comfort and environment of vehicles.

[Brief explanation of the drawing]

Figure 1 is a block configuration diagram of the air conditioning control device, Figure 2 is a graph showing the characteristics of gas sensor output changes and threshold level θ], and Figure 3 is a graph of sensor output σ] characteristics depending on temperature and humidity. , FIG. 4 is a diagram similar to FIG. 3 for other sensors, and FIG. 5 is a flowchart related to pollution detection and air conditioning control. In the drawing, 1 is a computer, 2 is an outside air sensor, and 3 is a computer.
is the internal air gas sensor, 6 is the follower, 9ζ is the damper, A
is the main routine, B is the subroutine for changing the threshold value, D is the bluechip for setting the delay time, a is the sensor output signal, b is the contamination detection threshold level, al is the upper limit value,
a2 is the lower limit value. Procedural amendment (voluntary) Director of the Patent Office Kazuinu Wakasugi1, Indication of the case Japanese Patent Application No. 58-2084653, Relationship with the person making the amendment Patent applicant (532) Honda Motor Co., Ltd.4, Agent Person 5゛ Date of amendment order Voluntary = 6 - = Addendum 1 GA・Invention 2 Amendment 6, No subject of amendment Description (2) The column for the title of the invention is revised as follows. In the third line of page 1 of the specification, the statement ``Method for detecting air pollution in a vehicle air conditioning control system'' has been corrected to read ``Method for detecting air pollution in an automatic air conditioning control system for a vehicle.'' (3. The Detailed Description of the Invention column is corrected as follows. ←) On page 3, line 12 of the specification, it says [... and sensor output]. The contamination detection threshold level is output from the sensor], and in the 14th line of the same page, it is corrected to read ``Set the range,'' instead of ``Set the range.'' (c) Page 12, line 13, line 14, 1 of the specification
Page 4, line 5, line 12, line 18, line 20,
In the first line of page 15, the word "threshold" is corrected to "threshold level." Attachment ``2. Claims In an automatic air conditioning control device for a vehicle, a pollution detection threshold level is set based on an output signal of an air pollution sensor, and the pollution detection threshold level is determined based on a change in the sensor output signal. The contamination detection threshold level is set to a change range having at least an upper limit, and the contamination detection threshold level is changed to follow the sensor output signal at an arbitrarily determined change rate within the change range, so that the sensor output signal An air pollution detection method for an automatic air conditioning control device for a vehicle, characterized in that air pollution is determined to be present only when the detection threshold level is exceeded.

Claims (1)

[Claims] In a vehicle air conditioning control device, a pollution detection threshold level is set based on the output signal of an air pollution sensor, and
A change range having at least an upper limit is set for the change in the sensor output signal, and the contamination detection threshold level is changed to follow the sensor output signal at an arbitrarily determined rate of change within the change range; An air pollution detection method for an air conditioning control device for a vehicle, characterized in that a state of pollution is determined only when the sensor output signal exceeds a pollution detection threshold level.