JP3255318B2 - Vehicle air conditioner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner for a vehicle, and more particularly to an air conditioner for a vehicle in which the degree of contamination of the outside air is detected by a gas sensor and the intake of the outside air can be adjusted in accordance with the output of the gas sensor. Regarding improvement.

[0002]

2. Description of the Related Art Conventionally, as an air conditioner for a vehicle such as an automobile, the degree of contamination of air outside the vehicle is detected by a gas sensor, and an air intake mode is switched between an inside air circulation mode and an outside air introduction mode according to the output of the gas sensor. There has been known a device in which the intake of air outside the vehicle can be automatically adjusted by appropriately switching the air conditioner (for example, Japanese Patent Laid-Open No. 59-237).
No. 22). By adopting such a configuration,
For example, when the outside air pollution level is high, such as when waiting for a traffic light on a congested road, the air intake mode of the air conditioner is automatically set to the inside air circulation mode, and the dirty air outside the vehicle enters the cabin. On the other hand, if the outside air is relatively clean (low pollution level), such as when driving in suburbs, the air intake mode is automatically switched to the outside air introduction mode, and fresh air outside the vehicle is prevented. It is possible to automatically set an appropriate air intake mode in accordance with the degree of contamination of outside air, such as by guiding air into the vehicle interior.

As a gas sensor for detecting the degree of contamination of air, for example, a metal oxide semiconductor such as tin oxide is used. When a reducing (flammable) gas reacts, air in the sensor (semiconductor) is contaminated or released into the sensor, causing the resistance of the sensor itself to change. A device for detecting the degree is conventionally known. For example, this type of gas sensor has a low resistance due to the presence of electrons in the sensor itself, for example, when tin oxide (SnO ₂ ) constituting an n-type semiconductor is used as the sensor. There is (that is, current flows well).
When this sensor is in the normal atmosphere, that is, in an atmosphere where the degree of air pollution is normal or lower and the oxygen (O ₂ ) concentration is a certain level or more, oxygen is easily adsorbed on the sensor surface. As shown in the following equation, oxygen near the sensor surface adsorbs negative charges while restraining electrons (e ⁻ ) inside the sensor. 1 / 2O ₂ + 2e ⁻ → O ² -... As a result, the sensor (tin oxide semiconductor) has a high resistance because the number of electrons inside the sensor decreases.

Here, when the degree of air pollution around the sensor, that is, the concentration of hydrogen (H ₂ ) or carbon monoxide (CO) increases, the surface of the sensor and these gases easily react with each other.
These combustible gases react with the adsorbed oxygen gas already adsorbed on the sensor surface. Taking the case of CO as an example, the following oxidation reaction (combustion) occurs. _{^{CO + O 2- → CO 2 +}} 2e - ...... As a result, the oxygen which has been adsorbed on the sensor surface is released into the atmosphere as oxidation product (carbon dioxide), the electrons in the sensor oxygen had restrained Released. That is, the sensor will return to low resistance as the electrons inside it increase.

As described above, the amount of oxygen adsorbed on the sensor surface side increases and decreases depending on the atmosphere surrounding the sensor, and the resistance value of the sensor itself changes depending on the amount of oxygen adsorption. Therefore, the change in the resistance value of the sensor itself is detected. By doing so, the atmospheric state around the sensor, that is, the degree of air pollution can be detected. In this case, the oxidation reaction (refer to the formula) on the sensor surface is unlikely to occur at room temperature. (° C.).

[0006]

However, when the outside air temperature is lower than a certain level, or when the traveling speed of the vehicle is high and the cooling effect of the traveling wind cannot sufficiently increase the temperature around the sensor, Even when heating with a heater, it may be difficult to stably maintain the sensor surface within the above-mentioned predetermined temperature range, and in such a case, the oxidation reaction of the combustible gas and the adsorbed oxygen according to the above formula is unlikely to occur. Become. Therefore, in such a case, the resistance value of the sensor itself is kept high for the actual air pollution degree,
There is a problem that the detection accuracy of the air pollution degree is reduced accordingly. It should be noted that examples of changes in the sensor resistance value when the ambient temperature and the vehicle speed are changed while the air pollution degree around the sensor is kept constant are schematically shown in the graphs of FIGS.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and when adjusting the intake of outside air in accordance with the output of a gas sensor for detecting the degree of contamination of outside air, the gas sensor is influenced by the traveling wind or the outside air temperature. It is an object of the present invention to provide a vehicle air conditioner that can automatically perform appropriate correction when a sensor output result changes due to a change in ambient temperature.

[0008]

SUMMARY OF THE INVENTION Accordingly, a first aspect of the present invention is directed to an air conditioner for a vehicle in which the intake of outside air can be adjusted in accordance with the output of a gas sensor for detecting the degree of pollution of outside air. Correction means for correcting the output result of the gas sensor in accordance with the vehicle speed, wherein the correction means corrects the output result of the gas sensor in a direction in which the higher the vehicle speed, the higher the degree of contamination of the outside air. It is characterized by the following.

According to a second aspect of the present invention, there is provided a vehicle air conditioner wherein the intake of outside air can be adjusted in accordance with the output of a gas sensor for detecting the degree of pollution of outside air. Correction means for correcting a determination criterion for determining the degree of contamination of the outside air based on the vehicle speed based on the vehicle speed, wherein the correction means corrects the determination criterion in a direction in which the determination criterion becomes stricter as the vehicle speed increases. It is what it was.

Further, a third invention of the present application is characterized in that, in the first or second invention, the correction means performs a correction corresponding to an outside air temperature in addition to a correction corresponding to a vehicle speed. Things.

Further, according to a fourth invention of the present application, in the third invention, the correction means is arranged such that as the vehicle speed increases,
The output result of the gas sensor is corrected in the direction in which the outside air pollution degree is determined to be high, and the output result of the gas sensor is corrected in the direction in which the outside air pollution degree is determined to be low as the outside air temperature is high. It is characterized by the following.

Further, according to a fifth aspect of the present invention, in the third aspect, the correction means is arranged such that the higher the vehicle speed is,
It is characterized in that the criterion for determining the degree of contamination of the outside air based on the output result of the gas sensor is corrected in a stricter direction, and the higher the outside air temperature, the more the criterion is corrected in a direction in which the criterion becomes loose. Things.

[0013]

According to the first aspect of the present invention, since the correction means is provided, the output result of the gas sensor is determined in accordance with the vehicle speed. In the direction where the degree of air pollution is determined to be high,
Can be corrected. Therefore, for example, the vehicle speed is high,
Even if the temperature around the sensor cannot be sufficiently increased due to the influence of the traveling wind and the sensor shows an output tendency that the air pollution degree is determined to be lower than the actual air pollution degree, this is effectively corrected. be able to. That is, even when the sensor output result changes due to a change in the ambient temperature of the gas sensor due to the influence of the traveling wind, this can be appropriately corrected and the detection accuracy when detecting the degree of contamination of the outside air can be increased. .

According to the second aspect of the present invention, since the correction means is provided, a criterion for determining the degree of air pollution outside the vehicle based on the output result of the gas sensor is determined in accordance with the vehicle speed. Specifically, the correction can be made in such a direction that the higher the vehicle speed is, the stricter the criterion becomes. Therefore, for example, when the vehicle speed is high, the temperature around the sensor cannot be sufficiently increased due to the influence of the traveling wind, and the sensor shows an output tendency such that the pollution degree is determined to be lower than the actual air pollution degree. However, an effective measure can be taken by correcting the criterion for determining the degree of contamination of the outside air on the basis of the output result so as to be strict. In other words, even when a change occurs in the sensor output result due to a change in the ambient temperature of the gas sensor due to the influence of the traveling wind, the determination criterion is appropriately corrected and the determination accuracy when determining the degree of contamination of the outside air is improved. Can be enhanced.

Further, according to the third aspect of the present invention, basically the same effects as those of the first or second aspect can be obtained. In addition, since the correction means can perform a correction according to the outside air temperature in addition to a correction according to the vehicle speed, the ambient temperature of the gas sensor changes due to the influence of the outside air temperature in addition to the influence of the traveling wind. However, even when the sensor output result changes accordingly, more appropriate correction is performed in consideration of the influence of the outside air temperature, and the detection accuracy or determination accuracy of the degree of contamination of the outside air can be further improved.

Further, according to the fourth invention of the present application,
Basically, the same effects as in the third aspect can be obtained. In particular, the correction means can correct the correction according to the outside air temperature, specifically, the output result of the gas sensor as the outside air temperature increases, in the direction in which the degree of contamination of the outside air is determined to be low. . Therefore, for example, even when the outside air temperature is high and the sensor shows an output tendency such that the pollution degree is determined to be higher than the actual air pollution degree, this can be effectively corrected. That is, if a change occurs in the sensor output result due to a change in the ambient temperature of the gas sensor, a more appropriate correction should be made in consideration of the influence of the outside air temperature in addition to the influence of the traveling wind when correcting the change. Therefore, the detection accuracy when detecting the degree of air pollution outside the vehicle can be further improved.

Further, according to the fifth invention of the present application,
Basically, the same effects as in the third aspect can be obtained. In particular, regarding the correction in accordance with the outside air temperature, specifically, the higher the outside air temperature is, the less the criterion for determining the degree of contamination of the outside air based on the output result of the gas sensor is reduced. Therefore, for example, even when the outside air temperature is high and the sensor shows an output tendency such that the pollution degree is determined to be higher than the actual air pollution degree, it can be corrected based on the output result. This can be dealt with effectively by correcting the criterion for determining the degree of pollution of the outside air to be loose. That is, when a change occurs in the sensor output result due to a change in the ambient temperature of the gas sensor, a more appropriate correction that takes into account the influence of the outside air temperature in addition to the influence of the traveling wind when correcting the above-described determination criterion is performed. It is possible to further improve the determination accuracy when determining the degree of air pollution outside the vehicle.

[0018]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is an overall configuration diagram schematically illustrating the outline of the configuration of the vehicle air conditioner according to the present embodiment. As shown in this figure, the air conditioner 10 cools the conditioned air by a blower unit 11 that takes in the conditioned air and sends it into the device 10 in order from the upstream side and an evaporator 25 that has a cooling function by evaporating a liquid refrigerant, for example. A cooling unit 12 for heating the conditioned air by a heater core 26 for introducing and circulating cooling water for an engine (not shown), and the heater unit 13 supplies the conditioned air to the passenger compartment. It is connected to a duct 16. Each terminal of the air conditioning duct 16 is mainly provided with vent outlets 17,..., 17 for blowing conditioned air toward the head and upper body of the occupant, a heat outlet 18 for blowing conditioned air mainly from the feet of the occupant, and a front port. And defroster outlets 19,..., 19 for blowing conditioned air toward a side window glass (not shown).

The blower unit 11 includes the outside air intake 2
1a, an inside air intake 21b, and an inside / outside air switching damper 24; an air intake box 21; a blower fan 22 for taking in outside air or inside air via the air intake box 21 and supplying it to the downstream side; And a blower motor 23 for driving the rotation of the blower 22.
And when setting the air-conditioning state by manual operation,
By operating an operation lever or button for setting an air intake mode provided on an air-conditioning operation panel (not shown), a damper actuator 30 for opening and closing the inside / outside air switching damper 24 is operated, and the inside / outside air switching damper 24 is operated. The outside air, the inside air, or the air in which both are mixed are introduced into the apparatus 10 by adjusting the opening degree of the air. In addition, by controlling the rotation speed of the blower fan 22, the amount of air taken into the air conditioner 10 (to the vehicle interior) can be adjusted. As described in detail later, by setting the air intake mode to an auto mode, the drive control of the damper actuator 30 is automatically performed in accordance with the degree of contamination of the outside air.
The intake of outside air can be adjusted.

Further, the heater unit 13 is provided with air mix doors 27 and 28 for changing the flow direction of the air passing through the cooling unit 12 and adjusting the flow rate of the air passing through the heater core 26 to perform manual setting. At this time, the air mix doors 27 and 2 are operated by operating a temperature control lever of an air conditioning operation panel (not shown).
By adjusting the opening of 8, the temperature of the conditioned air can be adjusted. Further, the air conditioning duct 16 is provided with a vent door 31 and a heat door 3 in order to adjust the amount of conditioned air blown out from each of the air outlets 17, 18, and 19.
2 and a defroster door 33 are provided.
By adjusting the opening degrees of 1, 32, and 33, the air-conditioning air blowing mode can be switched. When the manual setting is performed, the three doors 31, 32, and 33 are interlocked with each other by operating an operation lever or a button for setting a blowing mode provided on an air conditioning operation panel (not shown). The opening degree of each of the doors 31, 32, 33 is adjusted by operating the doors. The temperature setting of the conditioned air and the setting of the blowing mode are described in the air conditioner 10.
By setting the operation mode to the automatic mode, it is possible to automatically set the optimum temperature and the blow-out mode according to the air-conditioning state of the vehicle interior and the like.

In the air conditioner 10 according to the present embodiment, for example, when waiting for a traffic light on a congested road,
When the degree of pollution of the outside air is high, the air intake mode of the air conditioner 10 is automatically set to the inside air circulation mode to prevent the outside air of the vehicle from being introduced into the vehicle interior.
The air outside the vehicle is relatively clean, such as when traveling in the suburbs
If the air pollution mode is low, the air intake mode is automatically switched to the outside air introduction mode to guide fresh air outside the vehicle into the cabin. A so-called gas sensor for detecting the degree of air pollution outside the vehicle is provided in order to automatically carry out the above-mentioned operations. Although not specifically shown in FIG. 1, the gas sensor is provided in, for example, an outside air intake system of the air conditioner 10 (for example, in a passage of an outside air intake 21 a of the air intake box 21). The degree of contamination of the outside air taken into the air conditioner 10 can be detected.

The above-mentioned gas sensor, as a single sensor,
For example, it is formed of a metal oxide semiconductor such as tin oxide (SnO ₂ ). As shown in FIG. 2, a heater 4 is provided to heat the semiconductor sensor 3 to a predetermined temperature range.
The heating unit 4 and the semiconductor sensor 3 form a sensing unit 2. The sensor unit 1 is configured by adding a fixed resistor 5 to the sensing unit 2. Both ends of the sensor unit 1 are connected to a battery 6. When a battery voltage (Vb volt) is applied between both ends of the sensor unit 1, the voltage value (Vr volt) between both ends of the fixed resistor 5 is adjusted. By measuring, the semiconductor sensor 3
(Sensor resistance: Rs) can be calculated.

That is, the sensor unit 1 outputs a voltage value Vr across the fixed resistor 5 as a sensor signal,
This sensor signal is input to the air intake mode control unit 40 of the air conditioner 10 via the A / D (analog / digital) converter 8. In the control unit 40, the sensor signal Vr that has been digitally converted by the A / D converter 8 is converted into the sensor resistance Rs of the semiconductor sensor 3 by the Rs conversion unit described below based on the following equation. Rs = Rr (Vb / Vr-1) Basically, the damper actuator 30 is driven using the sensor resistance Rs as a control signal, and the opening degree of the inside / outside air switching damper 24 is automatically adjusted. Has become.

The higher the degree of contamination around the semiconductor sensor 3 (that is, the degree of contamination of the outside air), the more actively the oxidation reaction of the above formula occurs on the sensor surface. The voltage value Vr between both ends of the resistor 5 increases. In addition, the higher the ambient temperature of the semiconductor sensor 3 (that is, the higher the outside air temperature or the lower the vehicle speed), the more the oxidation reaction of the formula on the sensor surface is promoted, so that the sensor resistance Rs becomes smaller, and therefore,
The voltage value Vr between both ends of the fixed resistor 5 increases. That is, in this case, the sensor resistance Rs appears lower than the actual air pollution degree. Conversely, when the ambient temperature of the semiconductor sensor 3 is low (when the outside air temperature is low, or when the vehicle speed is high), the sensor resistance Rs increases and the voltage value V
r becomes smaller. That is, in this case, the sensor resistance Rs
Will be kept high for the actual air pollution degree.

In the present embodiment, when the sensor output result changes due to a change in the ambient temperature of the semiconductor sensor 3 due to the influence of the running wind during the running of the vehicle, this is corrected appropriately and the air pollution degree is detected. In order to improve the accuracy, the air intake mode control unit 40 is provided with a correction means for correcting the output result of the sensor unit 1 according to the vehicle speed. Hereinafter, the air intake mode control unit 4
0 will be described. The air intake mode control unit 40 is mainly composed of a microcomputer, for example, and has an A / D converter 8 as shown in FIG.
A Rs converter 41 for converting the signal (sensor signal Vr) from the sensor unit 1 converted into a digital signal into a sensor resistance Rs of the semiconductor sensor 3 based on the above equation, and a memory 39 provided outside the control unit 40, for example. Vehicle speed correction coefficient determination which determines a correction coefficient (vehicle speed correction coefficient β) corresponding to a signal (vehicle speed signal v) from the vehicle speed sensor 7 which is digitally converted by the A / D converter 8 based on the correction map stored therein. And a correction calculation unit that calculates a correction value β · Rs of the sensor resistance Rs based on the vehicle speed correction coefficient β determined by the correction coefficient determination unit 42 and the sensor resistance Rs obtained by the Rs conversion unit 41. 43.

The air intake mode control unit 40 has a sensor resistance correction value for switching the open / close position of the inside / outside air switching damper 24 of the air intake box 21 between the inside air circulation mode position and the outside air introduction mode position. β
A reference value setting unit 44 for setting a reference value Rso as a reference for determining a threshold value of Rs, and the reference value Rso
And a comparison unit 45 for comparing the sensor resistance correction value β · Rs at each measurement time with the comparison unit 45.
Based on the result of the comparison, a control signal for the damper actuator 30 is output via the output unit 46, and the open / close position of the inside / outside air switching damper 24 is controlled.

Next, an example of the control of the air intake mode by the air intake mode control unit 40 according to the degree of contamination of the outside air will be described with reference to the flowchart of FIG. When the system is started, first, in step # 1, it is determined whether or not the system is in the initial stage of activation (that is, whether the measurement is the first time).
At 2, the reference value Rso is initialized. In the present embodiment, the initial value of the reference value Rso is set to, for example, 0 (zero) (0 → Rso). On the other hand, if the determination result in step # 1 is N
In the case of O, step # 2 is skipped and step #
3 is executed.

In step # 3, more preferably,
The elapsed time t after the system starts is a first predetermined value t ₁ (for example, 6
It is determined whether or not the time has reached (0 seconds) or more, and the next step (step # 4) is executed only when the answer is YES.
Although not specifically shown, the air intake mode control unit 40 is provided with a timer for measuring an elapsed time t after the system is started. Thus, since the elapsed time t after system startup not allowed to proceed control until reaching the first predetermined value t ₁ is in the initial start-up, which takes some time to rise of the heater 4,
The ambient temperature of the semiconductor sensor 3 is within a specified temperature range (for example, 3
This is because the measurement result of the degree of pollution of the outside air may be unstable.

In step # 4, the vehicle speed correction coefficient determining section 4
In 2, the vehicle speed correction coefficient β corresponding to the vehicle speed v is determined based on the vehicle speed correction map called from the memory 39. The vehicle speed correction coefficient β determined in this way is input to the correction calculation unit 43. As described above, as the vehicle speed v increases, it becomes more difficult to sufficiently increase the ambient temperature of the semiconductor sensor 3 due to the effect of the cooling effect of the traveling wind, and the resistance value Rs of the sensor 3 itself becomes a percentage of the actual air pollution degree. Kept high. That is, as the vehicle speed v increases, the semiconductor sensor 3 exhibits an output tendency such that the pollution degree is determined to be lower than the actual air pollution degree. The vehicle speed correction coefficient β
Is to correct this. FIG. 9 shows an example of a vehicle speed correction map used for this correction. As can be clearly understood from FIG. 9, the vehicle speed correction coefficient β is set to be the largest when the vehicle speed v is 0 (zero) (β = 1.0), and to decrease as the vehicle speed v increases. Therefore, the semiconductor sensor 3 generally shows an output tendency such that the higher the vehicle speed v, the lower the air pollution degree is determined to be than the actual air pollution degree (that is, the sensor resistance Rs is smaller than the actual air pollution degree). However, the output result (sensor resistance Rs) of the semiconductor sensor 3 is corrected in a direction in which the degree of air pollution is determined to be high (a direction in which the sensor resistance Rs is low) by using the correction coefficient β. Can be. That is, a change in the output tendency of the semiconductor sensor 3 accompanying a change in the vehicle speed v can be effectively corrected.

In step # 4, the vehicle speed correction coefficient β is determined, and in step # 5, the Rs converter 41 converts the sensor signal Vr from the sensor unit 1 digitally converted by the A / D converter 8 into the above-described signal. It is converted into the sensor resistance Rs of the semiconductor sensor 3 based on the equation. The value of the sensor resistance Rs is obtained from the Rs conversion unit 41 by the correction calculation unit 4.
3 is input. Then, in step # 6, a correction value β · Rs of the sensor resistance Rs is calculated based on the sensor resistance Rs and the vehicle speed correction coefficient β, and thereafter, the correction value β · Rs is used as the sensor resistance Rs ( Rs = β · Rs).

Next, in step # 7, it is determined whether or not the elapsed time t after the system startup has reached a _second predetermined value t ₂ (for example, 120 seconds). Control is performed. That is, step # 8
Then, it is determined whether or not the air intake mode is the outside air introduction mode. If YES, the corrected sensor resistance Rs (= β · Rs) is compared with the reference value Rso in step # 9. Then, the degree of contamination of the outside air becomes relatively high, and the corrected sensor resistance Rs (= β · Rs) becomes, for example, 80% of the reference value Rso.
If it is less than (0.8Rso) (step # 9: YES), the air intake mode is switched to the inside air circulation mode (step # 10). On the other hand, if the determination result in step # 8 is NO, that is, if the air intake mode is the inside air circulation mode, in step # 11, the corrected sensor resistance Rs (= β · Rs) is set to the reference value Rso. Is compared to And
The degree of pollution of the outside air becomes relatively low, and the corrected sensor resistance Rs (= β · Rs) is, for example, 90% (0.
9Rso) or more (step # 11: YES), the air intake mode is switched to the outside air introduction mode (step # 12). As described above, the sensor resistance Rs (= β) when the air intake mode is switched from the inside air mode to the outside air mode.
The reason why the threshold value (0.9Rso) of (Rs) is set to be higher than the threshold value (0.8Rso) when switching from the outside air mode to the inside air mode is that dirty air outside the vehicle when switching to the outside air mode is used. This is to more reliably prevent the vehicle from entering the vehicle interior.

Thereafter, in step # 13, the corrected sensor resistance Rs (= β · Rs) is compared with a reference value Rso.
If the sensor resistance Rs (= β · Rs) is larger than the reference value Rso (step # 13: YES), the reference value Rso
Is replaced by this sensor resistance Rs (= β · Rs). That is, the reference value Rso is equal to the larger value of the sensor resistance Rs.
When (= β · Rs) is detected, that is, when a state where the outside air is cleaner is detected, the value indicating the clean state is updated. Note that after the elapsed time t from system startup has exceeded a first predetermined time t _1, until the second reaches a predetermined value t ₂ (step # 7: NO) between the actual air intake mode control Instead, only the update of the reference value Rso is performed by taking in the value of the sensor resistance Rs (see step # 13 and step # 14). in this way,
The elapsed time t from system startup is not performed air intake mode control reaches a predetermined value t ₂ of the second, the until after this much time after the start of activation, the ambient temperature of the semiconductor sensor 3 Within a specified temperature range (for example, 300 to 40
At 0 ° C.), the measurement result of the degree of pollution of the air outside the vehicle may still be unstable.

As described above, according to this embodiment, the air intake mode control unit 40 determines the vehicle speed correction coefficient (vehicle speed correction coefficient β) corresponding to the vehicle speed v based on the correction map. And a correction calculation unit 43 for calculating a correction value β · Rs of the sensor resistance Rs based on the vehicle speed correction coefficient β determined by the correction coefficient determination unit 42. The correction value β
Since Rs is set to be small, the output result of the sensor unit 1 is determined according to the vehicle speed v, specifically, the vehicle speed v
Is higher, the output result of the sensor unit 1 can be corrected in a direction in which the degree of contamination of the outside air is determined to be higher. Therefore, for example, the vehicle temperature v is high, and the ambient temperature of the semiconductor sensor 3 cannot be sufficiently increased due to the influence of the traveling wind.
Even when the sensor 3 shows an output tendency such that the air pollution degree is determined to be lower than the actual air pollution degree, this can be effectively corrected. That is, even if the sensor output result changes due to a change in the ambient temperature of the sensor 3 due to the influence of the traveling wind, it is necessary to appropriately correct this and improve the detection accuracy when detecting the degree of contamination of the outside air. You can.

In the above embodiment (hereinafter referred to as the first embodiment), the output result of the sensor unit 1 is changed according to the vehicle speed.
Although the (sensor resistance Rs) is corrected, the reference value for determining the degree of contamination of the outside air may be corrected according to the vehicle speed instead. Less than,
A second embodiment of the present invention will be described. In the following description, components having the same configuration and operation as those in the first embodiment are denoted by the same reference numerals, and further description is omitted.

As shown in FIG. 5, the air intake mode control unit 50 according to the present embodiment has a sensor signal V from the sensor unit 1 which is digitally converted by the A / D converter 8.
Let r be the sensor resistance Rs of the semiconductor sensor 3 based on the above equation.
And an open / close position of the inside / outside air switching damper 24 of the air intake box 21 between the inside air circulation mode position and the outside air introduction mode position based on the sensor resistance Rs obtained by the Rs conversion unit 51. A reference value setting unit 53 for setting a reference value Rso serving as a reference for determining a threshold value of the sensor resistance value Rs when switching between the two, and a vehicle speed signal from the vehicle speed sensor 7 based on a correction map stored in the memory 49.
a vehicle speed correction coefficient determining unit 52 that determines a correction coefficient (vehicle speed correction coefficient ε) according to v, the vehicle speed correction coefficient ε determined by the correction coefficient determining unit 52, and the reference value Rso obtained by the reference value setting unit 53. And the correction value Rso ′ (= ε ·
Rso). Further, the air intake mode control unit 50 is provided with a comparison unit 55 for comparing the corrected reference value Rso ′ with the sensor resistance Rs at each measurement time obtained by the Rs conversion unit 51. A control signal for the damper actuator 30 is output via the output unit 56 based on the comparison result of the comparison unit 55, and the open / close position of the inside / outside air switching damper 24 is controlled.

Next, an example of control of the air intake mode by the air intake mode control unit 50 according to the degree of contamination of the outside air will be described with reference to the flowchart of FIG. After the system starts, step # 21
From step # 23 to step # 23, exactly the same step contents as steps # 1 to # 3 (see FIG. 4) in the first embodiment are executed. In step # 24, the vehicle speed correction coefficient determination unit 52 determines a correction coefficient (vehicle speed correction coefficient ε) corresponding to the vehicle speed v based on the vehicle speed correction map called from the memory 49. The vehicle speed correction coefficient ε thus determined is input to the correction calculation unit 54.

As described above, as the vehicle speed v increases,
The semiconductor sensor 3 shows an output tendency such that the pollution degree is determined to be lower than the actual air pollution degree, and the vehicle speed correction coefficient ε sets the reference value Rso according to the vehicle speed in response to the output tendency. It is to be corrected. FIG. 10 shows an example of a vehicle speed correction map used for this correction. As can be clearly understood from this figure, the vehicle speed correction coefficient ε is set to be the smallest (ε = 1.0) when the vehicle speed v is 0 (zero), and to increase as the vehicle speed v increases. Therefore, in general, the vehicle speed
As v becomes higher, the semiconductor sensor 3 shows an output tendency such that the pollution degree is determined to be lower than the actual air pollution degree.
(That is, the sensor resistance Rs is higher than the actual air pollution degree.) However, by using the correction coefficient ε, the air pollution degree is determined when the open / close position of the inside / outside air switching damper 24 is switched. In the direction of stricter standards (that is,
(The direction in which the reference value Rso increases). That is, the reference value Rso can be corrected according to a change in the output tendency of the semiconductor sensor 3 with a change in the vehicle speed v.

In step # 24, the vehicle speed correction coefficient ε is determined. In step # 25, the same processing as in step # 5 in the first embodiment is executed. 3 is converted into the sensor resistance Rs. The value of this sensor resistance Rs is R
The data is input from the s conversion unit 51 to the reference value setting unit 53. Then, in step # 26, a correction value Rso ′ (= ε · Rso) of the reference value Rso is calculated based on the reference value Rso corresponding to the sensor resistance Rs and the vehicle speed correction coefficient ε, and thereafter, the reference value is updated. This correction value Rso 'is used as a reference value except for the processing (see steps # 33 and # 34).

Thereafter, from step # 27 to step # 3
Up to step 4, the same step contents as those from step # 7 to step # 14 in the first embodiment are executed, and the control of the air intake mode is performed. As described above, in each of these steps, the corrected reference value R
so 'is used as the reference value. However, updating the reference value
(See Steps # 33 and # 34), the actual uncorrected reference value Rso and the sensor resistance Rs
(Step # 33), and when the sensor resistance Rs is larger than the actual reference value Rso (step # 3).
3: YES), the actual reference value Rso is replaced by the sensor resistance Rs.

As described above, according to this embodiment, the air intake mode control unit 50 determines the vehicle speed correction coefficient (vehicle speed correction coefficient ε) according to the vehicle speed v based on the correction map. Based on the vehicle speed correction coefficient ε determined by the correction coefficient determination unit 52 and the reference value Rso that determines the criterion for determining the degree of air pollution in order to switch the open / close position of the inside / outside air switching damper 24. A correction calculating unit 54 for calculating a correction value Rso '(= ε · Rso);
Is set to be large, so that the criterion for determining the degree of contamination of the outside air based on the output result of the gas sensor depends on the vehicle speed v. Specifically, the higher the vehicle speed v, the more the above criterion is determined. Correction can be made in a direction that becomes more severe. Therefore, for example, the vehicle temperature v is high, and the ambient temperature of the semiconductor sensor 3 cannot be sufficiently increased due to the influence of the traveling wind.
Even when the sensor 3 shows an output tendency such that the degree of pollution is determined to be lower than the actual degree of air pollution, a reference value for determining a criterion for determining the degree of pollution of air outside the vehicle based on the output result. Rso can be dealt with effectively by correcting it so that the determination becomes strict. That is,
Even when a change occurs in the sensor output result due to a change in the ambient temperature of the sensor 3 due to the influence of the traveling wind, the above criterion is appropriately corrected, and the determination accuracy when determining the degree of contamination of the outside air is increased. You can do it.

In each of the above embodiments, when automatically controlling the air intake mode in accordance with the output of the sensor 3 for detecting the degree of contamination of the outside air, the influence of the traveling wind (ie, the vehicle speed v
Effect), but in addition to this, by taking into account the effect of changes in the outside air temperature,
The detection accuracy when detecting the degree of contamination of the outside air can be further enhanced. Next, a description will be given of a third embodiment in which a correction according to the outside air temperature is performed in addition to the correction according to the vehicle speed v.

As shown in FIG. 7, the air intake mode control unit 70 according to this embodiment converts the sensor signal Vr digitally converted by the A / D converter 68 into the sensor resistance of the semiconductor sensor 3 based on the above equation. A correction coefficient corresponding to the vehicle speed signal v from the vehicle speed sensor 7 based on an Rs conversion unit 71 for converting the data into Rs and a correction map called from the memory 69.
(Vehicle speed correction coefficient β). In addition, the A / D converter 68 according to the present embodiment includes, in addition to the vehicle speed signal v and the sensor signal Vr, an outside air temperature signal Ta from an outside air temperature sensor (not shown) for measuring the outside air temperature.
Is input, and this outside air temperature signal Ta
Is converted into a digital signal, which is then input to an outside reference air temperature setting unit 73 and a deviation calculation unit 74 provided in the air intake mode control unit 70.

The reference outside air temperature setting unit 73 calculates the outside air temperature after turning on the power or after resetting, for example, as the reference outside air temperature Tas.
The deviation calculating section 74 calculates the deviation (Tas) between the outside air temperature Ta and the reference outside air temperature Tas at each measurement time point.
-Ta) is calculated. Then, the calculation result is input to the outside temperature correction coefficient determination unit 75, and the correction coefficient determination unit 75
Based on the correction map called from the memory 69, a correction coefficient (outside air temperature correction coefficient α) corresponding to the outside air temperature deviation (Tas−Ta) is determined. Further, the air intake mode control unit 70 includes a vehicle speed correction coefficient β, an outside air temperature correction coefficient α determined by the correction coefficient determination units 72 and 75, and a sensor resistance Rs obtained by the Rs conversion unit 71.
And a correction calculation unit 76 for calculating a correction value αβRs of the sensor resistance Rs based on the above, and a switching operation of the open / close position of the inside / outside air switching damper 24 of the air intake box 21 between the inside air circulation mode position and the outside air introduction mode position. A reference value setting unit 77 is provided for setting a reference value Rso as a reference for determining a threshold value of the sensor resistance correction value αβRs. The reference value Rso and the sensor resistance correction value α at each measurement time are provided.
and a control signal for the damper actuator 30 is output via an output unit 79 based on the comparison result of the comparison unit 78, and the open / close position of the inside / outside air switching damper 24 is provided. Is controlled.

The control of the air intake mode by the air intake mode control unit 70 according to the degree of contamination of the air outside the vehicle follows a control flow similar to that shown in the flowchart (see FIG. 4) for explaining the first embodiment. Can be performed. However, in the present embodiment, in the step of determining the correction coefficient (FIG. 4: Step # 4), the vehicle speed correction coefficient β
And the outside air temperature correction coefficient α are determined respectively. In this case, when determining the vehicle speed correction coefficient β, for example, the correction map shown in FIG. 9 is used as in the case of the first embodiment. FIG. 11 shows an example of a correction map used for determining the outside air temperature correction coefficient α. As can be clearly understood from FIG. 11, when the outside air temperature deviation (Tas−Ta) is 0 (zero), the correction coefficient α = 1 is set as a reference. As the deviation (Tas−Ta) becomes smaller, that is, the outside air temperature Ta Is set so that the outside air temperature correction coefficient α becomes larger as the value of.

Therefore, in general, as the outside air temperature Ta increases, the semiconductor sensor 3 shows an output tendency such that the pollution degree is determined to be higher than the actual air pollution degree (that is, the output degree is higher than the actual air pollution degree). Although the sensor resistance Rs is low, the output result of the semiconductor sensor 3 (sensor resistance Rs) is determined by using the correction coefficient α in the direction in which the air pollution degree is determined to be low (that is, the sensor resistance Rs is high). Direction). That is, the sensor output result Rs can be corrected according to a change in the output tendency of the semiconductor sensor 3 due to a change in the outside air temperature Ta.

As described above, according to the present embodiment, the vehicle speed v is supplied to the air intake mode control unit 70.
Since the vehicle speed correction coefficient determination unit 72 for determining the correction coefficient (vehicle speed correction coefficient β) according to the present embodiment is provided, basically the same effects as those of the first or second embodiment can be obtained. Moreover, in addition to the above, the air intake mode control unit 70 is provided with an outside air temperature correction coefficient determining section 75 for determining a correction coefficient (outside air temperature correction coefficient α) corresponding to the outside air temperature Ta, and each of the correction coefficient determining sections 72 and 75. The correction calculation unit 76 that calculates the correction value αβRs of the sensor resistance Rs based on the correction coefficients β and α determined in the above is provided. In particular, regarding the correction according to the outside air temperature Ta, specifically, the outside air temperature Ta As a result, the output result (sensor resistance Rs) of the sensor 3 can be corrected in a direction in which the degree of contamination of the outside air is determined to be low.

Therefore, for example, even when the outside air temperature Ta is high and the sensor 3 shows an output tendency that the air pollution degree is determined to be higher than the actual air pollution degree, this can be effectively corrected. That is, when a change occurs in the sensor output result due to a change in the ambient temperature of the sensor 3, more appropriate correction is performed in consideration of the influence of the outside air temperature in addition to the influence of the traveling wind when correcting the change. As a result, the detection accuracy when detecting the degree of air pollution outside the vehicle can be further improved.

Next, instead of correcting the sensor output result, the reference value for determining the degree of contamination of the outside air is determined by the vehicle speed v
A description will be given of a fourth embodiment of the present invention in which correction is made according to the outside air temperature Ta. FIG. 8 is a block diagram of the air intake mode control unit 80 according to the fourth embodiment. As shown in this figure, the air intake mode control unit 80 according to the present embodiment includes a Rs for converting the digitally converted sensor signal Vr into a sensor resistance Rs of the semiconductor sensor 3 in the same manner as in the above-described embodiments. Converter 8
1, a vehicle speed correction coefficient determining unit 82 that determines a correction coefficient (vehicle speed correction coefficient ε) according to the vehicle speed signal v based on a correction map called from the memory 99, for example, as in the case of the third embodiment, Reference outside air temperature setting unit 83 that sets the outside air temperature after power-on or after reset as reference outside air temperature Tas
And the outside air temperature Ta and the reference outside air temperature Tas at each measurement time point.
And a correction coefficient (outside air temperature) corresponding to the outside air temperature deviation (Tas−Ta) based on the calculation result and a correction map called from the memory 99. Outside temperature correction coefficient determining unit 8 for determining the correction coefficient δ)
5 is provided.

The air intake mode control unit 80 has a sensor resistance Rs obtained by the Rs conversion unit 81.
A reference value Rs serving as a reference for determining a threshold value of the sensor resistance value Rs when the open / close position of the inside / outside air switching damper 24 is switched between the inside air circulation mode position and the outside air introduction mode position based on
o, a correction value for the reference value Rso based on the reference value Rso, the vehicle speed correction coefficient ε, and the outside temperature correction coefficient δ determined by the correction coefficient determination sections 82 and 85. A correction calculation unit 87 for calculating Rso ′ (= δεRso) is provided, and a comparison unit 88 for comparing the corrected reference value Rso ′ with the sensor resistance value Rs at each measurement time is provided. A control signal for the damper actuator 30 is output via the output unit 89 based on the comparison result of the comparison unit 88, and the inside / outside air switching damper 24
Is controlled.

The control of the air intake mode by the air intake mode control unit 80 in accordance with the degree of contamination of the air outside the vehicle follows a control flow similar to that shown in the flowchart (see FIG. 6) for explaining the second embodiment. Can be performed. However, in this embodiment, in the step of determining the correction coefficient (FIG. 6: step # 24), both the vehicle speed correction coefficient ε and the outside air temperature correction coefficient δ are respectively determined. In this case, when determining the vehicle speed correction coefficient ε, for example, the second
The correction map shown in FIG. 10 is used as in the case of the embodiment. FIG. 12 shows an example of a correction map used for determining the outside temperature correction coefficient δ. As can be clearly understood from FIG. 12, when the outside air temperature deviation (Tas−Ta) is 0 (zero), the correction coefficient δ = 1 is set as a reference, and as the deviation (Tas−Ta) becomes smaller, that is, the outside air temperature Ta Is higher,
The outside temperature correction coefficient δ is set to be small.

Therefore, in general, as the outside air temperature Ta increases, the semiconductor sensor 3 exhibits an output tendency such that the pollution degree is determined to be higher than the actual air pollution degree (that is, the output tendency is higher than the actual air pollution degree). The sensor resistance Rs becomes low), but by using the correction coefficient δ, the inside / outside air switching damper 2
4 in order to switch the open / close position and determine the air pollution degree in a direction in which the determination standard becomes loose (that is, the reference value Rso
(In the direction in which becomes smaller). That is, the reference value Rso can be corrected according to a change in the output tendency of the semiconductor sensor 3 due to a change in the outside air temperature Ta.

As described above, according to the present embodiment, the vehicle speed v is supplied to the air intake mode control unit 80.
Since the vehicle speed correction coefficient determining unit 82 for determining the correction coefficient (vehicle speed correction coefficient ε) according to the above is provided, basically the same effects as in the first or second embodiment can be obtained. In addition, the air intake mode control unit 80 is provided with an outside air temperature correction coefficient determining section 85 for determining a correction coefficient (outside air temperature correction coefficient δ) according to the outside air temperature Ta, and each correction coefficient determining section 82, 85 And a correction calculation unit 87 that calculates a correction value Rso ′ of a reference value Rso that determines a criterion for determining the degree of air pollution based on the correction coefficients ε and δ determined in the above. Specifically, the correction can be made in such a direction that the higher the outside air temperature Ta, the more the above-mentioned criterion becomes looser.

Therefore, for example, even when the outside air temperature Ta is high and the sensor 3 shows an output tendency that the air pollution degree is determined to be higher than the actual air pollution degree, this can be effectively corrected. That is, when a change occurs in the sensor output result due to a change in the ambient temperature of the sensor 3, more appropriate correction is performed in consideration of the influence of the outside air temperature in addition to the influence of the traveling wind when correcting the change. This makes it possible to further enhance the determination accuracy when determining the degree of air pollution outside the vehicle.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a vehicle air conditioner according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram illustrating a configuration of a sensor unit and a transmission system of a sensor signal according to the first embodiment.

FIG. 3 is a block diagram of an air intake mode control unit according to the first embodiment.

FIG. 4 is a flowchart for explaining mode control by the air intake mode control unit according to the first embodiment.

FIG. 5 is a block diagram of an air intake mode control unit according to a second embodiment of the present invention.

FIG. 6 is a flowchart illustrating mode control by an air intake mode control unit according to a second embodiment.

FIG. 7 is a block diagram of an air intake mode control unit according to a third embodiment of the present invention.

FIG. 8 is a block diagram of an air intake mode control unit according to a fourth embodiment of the present invention.

FIG. 9 is a graph showing an example of a vehicle speed correction map for correcting a sensor output result according to a vehicle speed.

FIG. 10 is a graph showing an example of a vehicle speed correction map for correcting a reference value according to a vehicle speed.

FIG. 11 is a graph showing an example of an outside air temperature correction map for correcting a sensor output result according to an outside air temperature.

FIG. 12 is a graph showing an example of an outside air temperature correction map for correcting a reference value according to an outside air temperature.

FIG. 13 is a graph showing an influence of an outside air temperature on a sensor resistance value.

FIG. 14 is a graph showing an influence of a vehicle speed on a sensor resistance value.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Sensor unit 3 ... Semiconductor sensor 10 ... Vehicle air conditioner 24 ... Inside / outside air switching damper 40,50,70,80 ... Air intake mode control unit 42,52,72,82 ... Vehicle speed correction coefficient determination unit 43,54, 76, 87: Correction calculation unit 44, 53, 77, 86: Reference value setting unit 75, 85: Outside air temperature correction coefficient determination unit Rs: Sensor resistance value (output result) Rso: Reference value of sensor resistance Ta: Outside air temperature v … Vehicle speed α, δ… Outdoor temperature correction coefficient β, ε… Vehicle speed correction coefficient

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hiroshi Aso 3-1 Shinchi, Fuchu-cho, Aki-gun, Hiroshima Prefecture Inside Mazda Corporation (72) Inventor Eiji Ukita 3-1 Shinchi, Fuchu-cho, Aki-gun, Hiroshima Mazda (56) References JP-A-59-23722 (JP, A) JP-A-4-281813 (JP, A) JP-A-2-152515 (JP, A) JP-A-6-130014 (JP, A) A) Japanese Utility Model Hei 5-64762 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) B60H 1/24 661 B60H 1/24 B60H 3/06

Claims (5)

(57) [Claims] 1. A vehicle air conditioner wherein the intake of outside air can be adjusted according to the output of a gas sensor for detecting the degree of pollution of outside air. A correction means for correcting the output result of the gas sensor according to the vehicle speed. Wherein the correction means corrects the output result of the gas sensor in a direction in which the degree of contamination of the outside air is determined to be higher as the vehicle speed is higher. 2. An air conditioner for a vehicle, wherein the intake of outside air can be adjusted in accordance with the output of a gas sensor for detecting the degree of contamination of outside air, wherein the degree of outside air pollution is determined based on the output result of the gas sensor. An air conditioner for a vehicle, comprising: a correction unit that corrects a criterion for determination according to a vehicle speed, wherein the correction unit corrects the criterion in a direction in which the criterion becomes stricter as the vehicle speed increases. 3. A vehicle air conditioner according to claim 1, wherein said correction means performs a correction according to an outside air temperature in addition to a correction according to a vehicle speed. Air conditioner. 4. The vehicle air conditioner according to claim 3, wherein the correction means corrects the output result of the gas sensor in a direction in which the degree of contamination of the outside air is determined to be higher as the vehicle speed is higher. A vehicle air conditioner wherein the output result of the gas sensor is corrected in a direction in which the degree of contamination of the outside air is determined to be lower as the outside air temperature is higher. 5. The vehicle air conditioner according to claim 3, wherein the correction means sets a stricter criterion for determining the degree of contamination of outside air based on an output result of the gas sensor as the vehicle speed increases. An air conditioner for a vehicle, wherein the correction is performed in a direction in which the determination is made, and the determination criterion is corrected in a direction in which the determination criterion becomes looser as the outside air temperature increases.