JP7767202B2 - Vehicle air conditioning control device - Google Patents

Description

This invention relates to a vehicle air conditioning control device that switches and controls the airflow from foot vents to both foot vents and defroster vents to prevent windows from fogging up during heating and other conditions.

Conventionally, some vehicle air conditioning control devices are equipped with an automatic air conditioning function that automatically adjusts the temperature of the air conditioning device (hereinafter also referred to as air conditioner) to the temperature desired by the occupant.The temperature of the conditioned air is calculated based on detection signals from various sensors and controlled to be blown out from the optimal outlet (see, for example, Patent Document 1).

In order to prevent window fogging, some automatic air conditioning systems automatically switch the air outlets to blow conditioned air from the footwell and defroster outlets when certain conditions are met. Specifically, the system determines whether window fogging is occurring based on whether all or some of the detected values from the outside air temperature sensor, engine water temperature sensor, solar radiation sensor, vehicle speed sensor, and air conditioner outlet temperature sensor are above predetermined values, and then determines whether to switch the air outlets to prevent window fogging and performs the switching control.

Japanese Patent Application Publication No. 6-206435

However, if the determination of whether to control the air outlet switching is based on whether the detected values of the outside air temperature sensor, engine water temperature sensor, solar radiation sensor, vehicle speed sensor, and air conditioner outlet temperature sensor are above a predetermined value, it is not possible to accurately determine the occurrence of window fogging, which creates the problem of not being able to automatically switch the air outlets to prevent window fogging at the timing expected by the occupants.

The present invention aims to enable, for example, precise determination of the occurrence of window fogging, and, when automatic switching of air outlets is required, to accurately switch the air outlets that blow out conditioned air at the timing expected by the occupants.

In order to achieve the above-mentioned object, the vehicle air conditioning control device of the present invention controls switching from blowing conditioned air from foot vents to blowing conditioned air from foot vents and defroster vents to prevent window fogging, and includes wiper speed, outside air temperature, vehicle speed, solar radiation, and interior temperature detection units that detect wiper speed, outside air temperature, vehicle speed, solar radiation, and interior temperature, respectively, and uses preset fuzzy inference membership functions for each of the detection values from the detection units to determine whether the wiper speed is fast or slow, and the outside air temperature, using the bad weather rate based on the detected wiper speed value as a factor. The system is characterized by having a derivation unit that classifies the output values into high/low outside air temperature as an element, high/low vehicle speed as an element, high/low solar radiation as an element, and high/low interior vehicle temperature as an element, and derives a weighting correction value from a combination of at least two of these classification results; and a control unit that determines whether the weighting correction value derived by the derivation unit is equal to or greater than a preset value, and determines whether to blow conditioned air from the foot outlet or from both the foot outlet and the defroster outlet, and controls the switching.

With this configuration, using preset fuzzy inference membership functions for the detected values from each detection unit that detects wiper speed, outside air temperature, vehicle speed, solar radiation, and cabin temperature, the derivation unit classifies the wiper speed as fast or slow using the bad weather rate based on the detected wiper speed value as a factor, the outside air temperature as high or low using the detected outside air temperature as a factor, the vehicle speed as high or low using the detected vehicle speed as a factor, the solar radiation as high or low using the detected solar radiation as a factor, and the cabin temperature as high or low using the detected cabin temperature as a factor. A weighting correction value is derived from a combination of at least two of these classification results, and the control unit determines whether the derived weighting correction value is equal to or greater than a preset value. Depending on the determination result, the control unit determines whether to blow conditioned air from the foot vents or from both the foot vents and the defroster vent, and controls the switching.

As a result, a weighting correction value is derived using a fuzzy inference membership function, and if the derived weighting correction value is equal to or greater than a preset value, control is performed, such as switching to a state in which conditioned air is blown out from the foot vents and defroster vents. This eliminates the need to install a new sensor to determine whether or not an outlet switch is necessary, preventing the configuration from becoming complicated. Furthermore, compared to installing a new sensor, the cost of installing software to derive a weighting correction value using a fuzzy inference membership function is less than the cost of installing hardware for a new sensor. This simple, inexpensive configuration enables automatic switching of the vents blowing conditioned air with precision at the timing expected by vehicle occupants.

Furthermore, the weighting correction value derived by the derivation unit is for window fogging to determine whether or not the window is fogging, and the higher the degree of window fogging, the higher the weighting correction value.The control unit may determine that the window is fogging if the weighting correction value for window fogging is equal to or greater than a predetermined value, and control the state of air conditioning air being blown out from the foot vents and defroster vents.

With this configuration, the control unit determines that the windows are fogging if the weighting correction value for window fogging is equal to or greater than a predetermined value, and controls the state of conditioned air being blown out from the foot vents and defroster vents. This allows for precise determination of the occurrence of window fogging, and enables automatic switching of the vents blowing out conditioned air with precision at the timing expected by the occupants.

The vehicle may further include an engine water temperature detection unit and an air volume detection unit that detect the engine water temperature and the volume of the conditioned air, respectively. The derivation unit uses preset fuzzy inference membership functions for the detection values of the engine water temperature detection unit and the air volume detection unit to classify the detected engine water temperature as high/low and the detected air volume as strong/weak, using the detected engine water temperature as a factor, and derives a weighting correction value for hot flushes from a combination of these classification results to determine whether the occupant is hot flushed, the correction value increasing as the degree of hot flushes decreases. If the sum of the weighting correction value for window fogging and the weighting correction value for hot flushes derived by the derivation unit is equal to or greater than a preset value, the control unit may determine that the window is fogging and that hot flushes are not present, and control the state of the conditioned air being blown out from the foot vents and the defroster vents.

With this configuration, if the sum of the weighting correction value for window fogging and the weighting correction value for hot flush derived by the derivation unit is equal to or greater than a preset value, the control unit determines that there is window fogging but no hot flush, and controls the state of air conditioning air being blown out from the foot vents and defroster vents. This allows for precise determination of the state of window fogging and the occupant's state of hot flush, and enables automatic switching of the air conditioning air outlets at the timing expected by the occupant.

According to this invention, if the weighting correction value derived using the membership function of fuzzy inference is equal to or greater than a preset value, control is performed, such as switching to a state in which conditioned air is blown out from the foot vents and defroster vents. This makes it possible to automatically switch the vents that blow out conditioned air with precision at the timing expected by the vehicle occupants, with a simple and inexpensive configuration, without the need for a new sensor to determine whether or not the vents need to be switched. This is ideal for in-vehicle automatic air conditioners.

1 is a block diagram of a first embodiment of a vehicle air conditioning control device according to the present invention; FIG. 2 is an explanatory diagram of the operation of FIG. 1, showing an example of a membership function of the wiper speed. FIG. 2 is an explanatory diagram of the operation of FIG. 1, showing an example of a membership function of the outside air temperature. 2 is an explanatory diagram of the operation of FIG. 1, showing an example of a weighting correction value for window fogging. 2 is a flowchart illustrating the operation of FIG. 1 . FIG. 10 is a block diagram of a second embodiment of the present invention. 7 is a flowchart illustrating the operation of FIG. 6;

(First embodiment)
A first embodiment of the vehicle air conditioning control device of the present invention will be described in detail with reference to FIGS. 1 to 5. FIG.

Figure 1 shows a vehicle air conditioning control device 1 that controls an on-board automatic air conditioner, and includes a wiper speed sensor 2, an outside air temperature sensor 3, a vehicle speed sensor 4, a solar radiation sensor 5, and an inside vehicle temperature sensor 6, which are wiper speed, outside air temperature, vehicle speed, solar radiation, and inside vehicle temperature detection units that detect wiper speed, outside air temperature, vehicle speed, solar radiation, and inside vehicle temperature, respectively.

Then, the detection values from each sensor 2-6 are input into the derivation unit 7, and using membership functions preset in the membership function setting unit 8 for each of the detection values from each sensor 2-6, the derivation unit 7 classifies the wiper speed as fast/slow using the bad weather rate based on the detected wiper speed value as a factor, the outside temperature as high/low using the detected outside air temperature as a factor, the vehicle speed as high/low using the detected vehicle speed as a factor, the amount of solar radiation as high/low using the detected amount of solar radiation as a factor, and the interior temperature as high/low using the detected interior temperature as a factor, and derives a weighting correction value for window fogging from the combination of these classification results.

Here, the membership function setting unit 8 is configured, for example, by a memory, and stores a preset wiper speed membership function as shown in FIG. 2 for classifying wiper speeds into fast and slow using the bad weather rate based on the value detected by the wiper speed sensor 2 as a factor, and a preset outside air temperature membership function as shown in FIG. 3 for classifying outside air temperatures into high and low using the value detected by the outside air temperature sensor 3 as a factor. The membership function setting unit 8 also stores a preset vehicle speed membership function for classifying vehicle speeds into high and low using the value detected by the vehicle speed sensor 4 as a factor, a preset solar radiation membership function for classifying solar radiation into high and low using the value detected by the solar radiation sensor 5 as a factor, and a preset vehicle interior temperature membership function for classifying vehicle interior temperatures into high and low using the value detected by the vehicle interior temperature sensor 6 as a factor.

Now, the operation of deriving the weighting correction value by the deriving unit 7 will be described. Based on the detection values from the five sensors 2 to 6 shown in Fig. 1, the wiper speed is classified as fast or slow, and the outside air temperature, vehicle speed, amount of solar radiation, and interior temperature are each classified as high or low using membership functions preset in the membership function setting unit 8 as shown in Figs. 2 and 3. Each of these is classified into two states, so there are 32 possible combinations of these classification results, from 2 to ⁵ , as shown in Fig. 4. In this case, a "fast" wiper speed indicates bad weather and window fogging is likely, a "low" outside air temperature indicates that the outside of the vehicle is cold and window fogging is likely, a "high" vehicle speed indicates that the vehicle is traveling in a luminous flux and is cold and window fogging is likely, a "low" amount of solar radiation indicates that there is little sunlight and window fogging is likely, and a "high" interior temperature indicates that the inside of the vehicle is colder than the outside of the vehicle and window fogging is likely. The sum of the number of categories indicating that the window is prone to fogging is then derived as a weighted correction value by the derivation unit 7. In order to make it easy to determine whether or not the window is prone to fogging, as shown in Fig. 4, categories indicating a state in which the window is prone to fogging, i.e., "window fogging present", are not shaded, and categories indicating a state in which the window is not prone to fogging, i.e., "window not fogging", are shaded.

For example, the first combination in Figure 4, where the wiper speed is "fast," the outside air temperature is "low," the vehicle speed is "high," the amount of solar radiation is "low," and the interior temperature is "high," indicates "window fogging" with no shading in any of the five categories of wiper speed, outside air temperature, vehicle speed, amount of solar radiation, and interior temperature. Therefore, as shown in Figure 4, the derivation unit 7 derives "5," which is the sum of the five categories of wiper speed, outside air temperature, vehicle speed, amount of solar radiation, and interior temperature that indicate "window fogging," as the weighting correction value for window fogging to correspond to the presence of window fogging.

Furthermore, in the second combination in Figure 4, where the wiper speed is "fast," the outside air temperature is "low," the vehicle speed is "high," the amount of solar radiation is "low," and the vehicle interior temperature is "low," the four categories of wiper speed, outside air temperature, vehicle speed, and amount of solar radiation represent "window fogging" (without shading), while the "low" category of vehicle interior temperature in Figure 4 represents "window fogging" (with shading). Therefore, the derivation unit 7 derives "4," which is the sum of the four categories of wiper speed, outside air temperature, vehicle speed, and amount of solar radiation that represent "window fogging," as shown in Figure 4, as the weighting correction value for window fogging to correspond to the presence of window fogging.

Furthermore, in the 31st combination in Figure 4, where the wiper speed is "slow," the outside air temperature is "high," the vehicle speed is "low," the amount of solar radiation is "high," and the interior temperature is "high," the shaded areas of the wiper speed, the outside air temperature, the vehicle speed, and the amount of solar radiation are "slow," representing "no window fogging." However, only the unshaded area of the "high" interior temperature in Figure 4 represents "window fogging." Therefore, as shown in Figure 4, the derivation unit 7 derives "1" based on only one area of the interior temperature as the weighting correction value for window fogging to correspond to the presence of window fogging.

Furthermore, in the 32nd combination in Figure 4, where the wiper speed is "slow," the outside air temperature is "high," the vehicle speed is "low," the amount of solar radiation is "high," and the vehicle interior temperature is "low," all five categories of wiper speed, outside air temperature, vehicle speed, amount of solar radiation, and vehicle interior temperature represent the shaded "no window fogging" category, so the window fogging weighting correction value derived by the derivation unit 7 to correspond to the presence of window fogging is "0," as shown in Figure 4.

In this way, by creating a two-dimensional map as shown in Figure 4 and storing the combinations of wiper speed, outside air temperature, vehicle speed, solar radiation, and cabin temperature in memory, it is possible to easily derive a weighting correction value for window fogging corresponding to the number of "window fogging" categories from the two-dimensional map.

The control unit 9 then determines whether the weighting correction value derived by the derivation unit 7 is equal to or greater than a predetermined value. If the determination result is equal to or greater than the predetermined value, and the conditioned air is currently being blown from the foot vents, the control unit 9 controls the outlet switching unit 10 to switch the state of conditioned air being blown from the foot vents and the defroster vents.

Next, we will explain the control procedure for switching the air conditioning air outlet depending on whether the window is fogging up, with reference to Figure 5.

As shown in FIG. 5, when the detection values from the sensors 2-6 are input by the derivation unit 7 (step S1), the wiper speed is classified as fast or slow using the wiper speed membership function preset in the membership function setting unit 8 for the detection value from the wiper speed sensor 2 (step S2). The outside air temperature is classified as high or low using the outside air temperature membership function preset in the membership function setting unit 8 for the detection value from the outside air temperature sensor 3 (step S3). Similarly, the vehicle speed, solar radiation, and interior temperature are classified as high or low (steps S4-S6).

Then, based on the combination of the classification results of wiper speed, outside air temperature, vehicle speed, solar radiation, and cabin temperature shown in the two-dimensional map of Figure 4, the derivation unit 7 derives a weighting correction value for window fogging to correspond to the presence of window fogging (step S7). It is then determined whether the derived weighting correction value C is equal to or greater than a predetermined value C1 (C≧C1) (step S8). If the determination result is YES, it is determined that window fogging is present, and the control unit 9 controls the outlet switching unit 10 to switch the conditioned air to be blown from the foot outlet and defroster outlet (step S9), after which the operation ends. On the other hand, if the determination result in step S8 is NO, it is determined that window fogging is not present, and the control unit 9 controls the outlet switching unit 10 to switch the conditioned air to be blown from the foot outlet (step S10), after which the operation ends.

Therefore, according to the first embodiment described above, the derivation unit 7 derives a weighting correction value C for window fogging, using a fuzzy inference membership function preset in the membership function setting unit 8. If the derived weighting correction value C is equal to or greater than a preset value C1 (C≧C1), the control unit 9 controls the outlet switching unit 10 to switch the air conditioning air outlets to the footwell outlets and the defroster outlets. This allows for a more precise determination of window fogging than conventional methods that determine whether window fogging is present based on whether the wiper speed is faster or slower than a predetermined speed or whether the outside air temperature is higher or lower than a predetermined temperature, and allows for accurate automatic switching of the air conditioning air outlets at the timing expected by the occupant. Furthermore, since there is no need to install a new sensor, such as a humidity sensor, to detect window fogging, the configuration can be kept simple and inexpensive.

Furthermore, compared to installing a new humidity sensor, etc., the cost of installing software to derive weighting correction values using fuzzy inference membership functions is less than the cost of installing hardware such as a new humidity sensor. Therefore, with a simple and inexpensive configuration, it is possible to automatically switch the air outlets that blow out conditioned air with precision at the timing expected by the vehicle occupants.

Second Embodiment
Next, a second embodiment of the vehicle air conditioning control device of the present invention will be described in detail with reference to Figures 6 and 7. In Figure 6, the same reference numerals as those in Figure 1 of the first embodiment indicate the same or corresponding parts, and the following description will mainly focus on the differences from the first embodiment.

The vehicle air conditioning control device 1A shown in Figure 6 further includes the configuration of Figure 1, an engine water temperature sensor 11, and an air volume sensor 12, which are an engine water temperature detection unit and an air volume detection unit that detect engine water temperature and air volume, respectively. The membership function setting unit 8 stores, in addition to preset membership functions for each of the detection values of sensors 2-6, a preset engine water temperature membership function for classifying engine water temperature as high or low using the detection value of engine water temperature sensor 11 as a factor, and a preset air volume membership function for classifying air volume as strong or weak using the detection value of air volume sensor 12 as a factor, in order to determine whether the occupant is flushed.

The derivation unit 7 derives a weighting correction value corresponding to the presence of window fogging from the classification results using the membership functions shown in Figure 4, which indicate the likelihood of window fogging, as described above. In addition, the derivation unit 7 derives a weighting correction value corresponding to the absence of hot flushing using the membership functions for engine water temperature and airflow through a similar derivation process. The control unit 9 determines whether the sum C of the weighting correction value Ca corresponding to the presence of window fogging and the weighting correction value Cb corresponding to the absence of hot flushing is equal to or greater than a preset value C2. If the sum (Ca + Cb) is equal to or greater than the preset value C2, it is determined that the window is fogging and the presence of hot flushing is absent, and the outlet switching unit 10 is controlled to switch the air conditioner to blowing air from the foot outlets and the defroster outlets. This differs from the first embodiment in that the weighting correction value Cb corresponding to hot flushing is larger the lower the degree of hot flushing is, and smaller the higher the degree of hot flushing is.

Next, the control procedure for switching the air conditioning air outlet depending on whether the window is fogging up or whether the face is flushed in the second embodiment shown in Figure 6 will be explained with reference to Figure 7.

As shown in FIG. 7, when the detection values from the sensors 2-6 are input by the derivation unit 7 (step S21), the wiper speed is classified as fast or slow using the wiper speed membership function preset in the membership function setting unit 8 for the detection value from the wiper speed sensor 2 (step S22). The outside air temperature is classified as high or low using the outside air temperature membership function preset in the membership function setting unit 8 for the detection value from the outside air temperature sensor 3 (step S23). Similarly, the vehicle speed, solar radiation, and interior temperature are classified as high or low (steps S24-S26). Then, based on the combination of the classification results for wiper speed, outside air temperature, vehicle speed, solar radiation, and interior temperature shown in the two-dimensional map of FIG. 4, the derivation unit 8 derives a window fogging weighting correction value Ca to correspond to the presence of window fogging (step S27).

Furthermore, the engine water temperature is classified as high or low using the engine water temperature membership function preset in the membership function setting unit 8 for the value detected by the engine water temperature sensor 11 (step S28), and the air volume of the conditioned air is classified as strong or weak using the air volume membership function preset in the membership function setting unit 8 for the value detected by the air volume sensor 3 (step S29). Based on the combination of the engine water temperature and air volume classification results similar to the two-dimensional map of Figure 4, the derivation unit 7 derives a weighting correction value Cb for facial flushing to accommodate no facial flushing (step S30).

Then, the derivation unit 7 determines whether the sum of the weighting correction value Ca for window fogging derived in step S27 and the weighting correction value Cb for hot flushing derived in step S30 is equal to or greater than the preset value C2 (Ca + Cb ≥ C2) (step S31). If the determination result is YES, it is determined that there is window fogging and the occupant is not hot flushing, and the control unit 9 controls the outlet switching unit 10 to switch the conditioned air to be blown from the foot outlets and defroster outlets (step S32), after which the operation ends. On the other hand, if the determination result in step S31 is NO, it is determined that there is no window fogging and the occupant is hot flushing, and the control unit 9 controls the outlet switching unit 10 to switch the conditioned air to be blown from the foot outlets (step S33), after which the operation ends.

Accordingly, according to the second embodiment, if the sum of the weighting correction value Ca for window fogging and the weighting correction value Cb for facial flushing derived by the derivation unit 7 is equal to or greater than the preset value C2, the control unit 9 determines that the windows are fogging but the occupant is not flushed, and controls the state of conditioned air being blown out from the foot vents and defroster vents. This allows for precise determination of the state of window fogging and the state of occupant facial flushing, and enables automatic switching of the vents blowing out conditioned air with precision at the timing expected by the occupant.

The present invention is not limited to the above-described embodiments, and various modifications other than those described above are possible as long as they do not deviate from the spirit of the invention.

For example, in the first embodiment described above, a weighting correction value C for window fogging to deal with the presence of window fogging was derived using a preset fuzzy inference membership function for each of the detection values from sensors 2 to 6 that detect wiper speed, outside air temperature, vehicle speed, solar radiation, and cabin temperature, respectively. However, a weighting correction value for window fogging may also be derived using at least two of the preset fuzzy inference membership functions for each of the detection values from sensors 2 to 6.

Furthermore, examples of fuzzy inference membership functions in the above-described embodiment are shown in Figures 2 and 3, but the membership functions are not limited to those shown in Figures 2 and 3.

The present invention can also be applied to a vehicle air conditioning control device that switches from blowing conditioned air from the foot vents to blowing conditioned air from the foot vents and defroster vents to prevent windows from fogging up.

1, 1A... Vehicle air conditioning control device 2... Wiper speed sensor (wiper speed detection unit)
3...Outside air temperature sensor (outside air temperature detection unit)
4... Vehicle speed sensor (vehicle speed detection unit)
5...Solar radiation sensor (solar radiation detection unit)
6... Vehicle interior temperature sensor (vehicle interior temperature detection unit)
7: Derivation section 9: Control section 11: Engine water temperature sensor (engine water temperature detection section)
12...Air volume sensor (air volume detection unit)

Claims (3)

In a vehicle air conditioning control device that controls switching from a state in which conditioned air is blown from a foot outlet to a state in which conditioned air is blown from a foot outlet and a defroster outlet in order to prevent windows from fogging up,
a wiper speed, outside air temperature, vehicle speed, solar radiation, and vehicle interior temperature detection unit that detects a wiper speed, an outside air temperature, a vehicle speed, a solar radiation amount, and a vehicle interior temperature, respectively;
a derivation unit that uses a preset fuzzy inference membership function for each of the detection values by the detection units to classify the wiper speed into fast/slow using a bad weather rate based on the detected wiper speed as an element, high/low outside air temperature using the detected outside air temperature as an element, high/low vehicle speed using the detected vehicle speed as an element, high/low solar radiation using the detected solar radiation as an element, and high/low inside vehicle temperature using the detected inside vehicle temperature as an element, and derives a weighted correction value from a combination of at least two of these classification results;
a control unit that determines whether the weighting correction value derived by the derivation unit is equal to or greater than a preset value, and determines whether to blow conditioned air from the foot outlet or to blow conditioned air from both the foot outlet and the defroster outlet, and controls the switching. the weighting correction value derived by the derivation unit is for determining whether or not a window is fogging, and the higher the degree of fogging of the window, the higher the weighting correction value;
2. The vehicle air conditioning control device according to claim 1, wherein the control unit determines that the window is fogging up if the weighting correction value for window fogging is equal to or greater than a predetermined value, and controls the blowing state of conditioned air from the foot outlets and the defroster outlets. The vehicle further includes an engine water temperature detector and an air volume detector that detect an engine water temperature and an air volume of the air conditioning air, respectively.
The lead-out portion is
using membership functions of fuzzy inference preset for the detection values of the engine water temperature detection unit and the air volume detection unit, respectively, to classify the detected value of the engine water temperature as an element into high/low engine water temperature and the detected value of the air volume detection unit into strong/weak air volume, and deriving a weighted correction value for flushing for determining whether the occupant is flushed or not from a combination of these classification results, the correction value becoming higher as the degree of flushing becomes lower;
The control unit
3. The vehicle air conditioning control device according to claim 2, wherein if the sum of the weighting correction value for window fogging and the weighting correction value for facial flushing derived by the derivation unit is equal to or greater than a preset value, it is determined that there is window fogging and no facial flushing, and the air conditioning air blowing state from the foot outlets and the defroster outlets is controlled.