JP3085342B2 - 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 having a defroster switch (hereinafter abbreviated as DEF switch) for removing fogging of window glass.

[0002]

2. Description of the Related Art Conventionally, there is an air conditioner in which a DEF switch is set on an operation panel of an air conditioner in order to remove fogging on the inner surface of a window glass of a vehicle (Japanese Patent Publication No. 62-5892).
No. 6). The DEF switch discharges dehumidified air from the defroster outlet (hereinafter abbreviated as DEF outlet) to the inner surface of the window glass. When the DEF switch is turned on, an outside air mode is generally set to introduce outside air. Is performed, and by driving the refrigerant compressor of the refrigeration cycle, air having a low absolute humidity is blown to the window glass, and the fogging of the window glass is eliminated.

[0003]

However, in the conventional vehicle air conditioner in which the DEF switch is set, the fogging of the window glass is eliminated, and once the DEF switch is turned off, the humidity outside the cabin becomes lower. Since the window glass has not significantly changed from the time when it was fogged, after a while, the window glass becomes clouded again. For this reason, the DEF switch is turned on each time the window glass becomes cloudy, and the DEF switch is turned off each time the clouding is eliminated, which involves the trouble of repeatedly turning on and off the DEF switch. . By keeping the DEF switch turned on, the trouble of repeatedly turning the DEF switch on and off can be relieved, but it is necessary to always operate the refrigerant compressor at the maximum dehumidifying capacity. However, it is not preferable from the viewpoint of power saving. The present invention has been made based on the above circumstances, and an object of the present invention is to reduce troublesome switch operations in eliminating fogging of a window glass, and to save power of a refrigerant compressor. An object of the present invention is to provide an air conditioner.

[0004]

In order to achieve the above object, according to the present invention, a refrigeration cycle is provided together with a ventilation path for guiding air into a vehicle interior, a refrigerant compressor, a refrigerant condenser, and expansion means. The cooling and dehumidifying capacity is adjusted by the operation of the refrigerant compressor, and a refrigerant evaporator for cooling and dehumidifying the air in the ventilation passage and a driver's manual operation to notify that the vehicle compartment needs to be dehumidified. Dehumidification command signal output means for outputting a dehumidification command signal, and first control means for controlling the refrigerant compressor so as to increase the cooling and dehumidification capacity of the refrigerant evaporator when the dehumidification command signal is input. An air conditioner that performs economy control to reduce the cooling and dehumidifying capacity of the refrigerant evaporator as necessary, wherein when the input state of the dehumidifying command signal is released, the cooling and dehumidifying capacity of the refrigerant evaporator is reduced. It is referred to as technical means, further comprising a second control means for controlling the refrigerant compressor so as to be larger than the cooling dehumidification capacity before entering the dehumidification command signal.

According to a second aspect of the present invention, there is provided a refrigeration cycle including a ventilation path for introducing air into a vehicle interior, a refrigerant compressor, a refrigerant condenser, and expansion means, and cooling and dehumidification by the operation of the refrigerant compressor. The capacity is adjusted, a refrigerant evaporator that cools and dehumidifies the air in the ventilation path, and a dehumidification command signal output unit that outputs a dehumidification command signal indicating that it is necessary to dehumidify the cabin by a driver's manual operation. A first control means for controlling the refrigerant compressor so as to increase the cooling and dehumidifying ability of the refrigerant evaporator when the dehumidifying command signal is input, and the cooling and dehumidifying ability of the refrigerant evaporator is required. Air-conditioning state determining means for determining whether the air-conditioning state of the vehicle is in a transient state or a steady state in the air-conditioning in which economy control is performed in accordance with If it is determined that the air-conditioning state is a steady state, the cooling dehumidification capability of the refrigerant evaporator before the dehumidification command signal is input is changed according to the cancellation of the input state of the dehumidification command signal. Second control means for controlling the refrigerant compressor to be larger than the capacity,
If the air conditioning state determining means determines that the air conditioning state of the vehicle is in a transient state, the dehumidification command signal is released from the input state of the dehumidification command signal and the cooling / dehumidification capacity of the refrigerant evaporator is reduced by the dehumidification command signal. And a third control means for controlling the refrigerant compressor so as to return to the cooling / dehumidifying capacity before the input.

[0006]

The air conditioner according to the first aspect of the present invention has the following effects. By operating the refrigerant compressor, the cooling and dehumidifying ability of the refrigerant evaporator is adjusted, and the air in the ventilation passage is cooled and dehumidified. When the driver manually operates the dehumidification command signal output means to output a dehumidification command signal, the first control means controls the refrigerant compressor so as to increase the cooling and dehumidification capacity of the refrigerant evaporator. . Thereafter, when the dehumidification command signal is released, the second control means controls the refrigerant compressor so that the cooling / dehumidification capacity of the refrigerant evaporator is larger than the cooling / dehumidification capacity before the dehumidification command signal is input. Do. With the above control, it is possible to prevent the windowpane from fogging again after the dehumidification command signal is released. The “operation of the refrigerant compressor” is, for example, turning on / off an electromagnetic clutch or controlling the capacity of the refrigerant compressor. Also, "increase the cooling and dehumidifying capacity"
For example, maximizing the capacity of the refrigerant compressor controlled by a certain capacity to maximize the cooling and dehumidifying capacity, or turning on the electromagnetic clutch which is off.

The air conditioner of the present invention according to claim 2 is
The following operation is achieved. When the dehumidification command signal is released,
When the air-conditioning state determining means determines that the air-conditioning state of the vehicle is a steady state, the second control means
The refrigerant compressor is controlled such that the cooling and dehumidifying capacity of the refrigerant evaporator is larger than the cooling and dehumidifying capacity before the input of the dehumidifying command signal. That is, when the air-conditioning state of the vehicle is in a steady state, after outputting the dehumidification command signal to dehumidify the vehicle interior,
If the cooling and dehumidifying ability of the refrigerant evaporator is returned to the previous (before input of the dehumidifying instruction signal) when the dehumidifying command signal is released, there is a high possibility that the window glass becomes cloudy again. It is known that fogging of window glass occurs when the temperature of the window glass is equal to or lower than the dew point temperature of vehicle interior air. Also,
The window glass temperature increases as the temperature inside the vehicle interior increases.
Therefore, in a transient state in which the window glass temperature is changing, the window glass often clears even if the window glass becomes cloudy if the temperature becomes stable and the window glass temperature rises and stabilizes. On the other hand, in a steady state, that is, when the window glass temperature rises completely and is stable, under conditions where the window glass becomes cloudy, fogging always occurs. is there. Therefore, when the air-conditioning state of the vehicle is in a steady state, when the dehumidification command signal is released, the cooling dehumidification capacity of the refrigerant evaporator is made larger than the cooling dehumidification capacity before the dehumidification command signal is input, so that the window is opened. Glass fogging is prevented.

When the air conditioning state determining means determines that the air conditioning state of the vehicle is in a transient state, the third control means determines the cooling / dehumidifying capacity of the refrigerant evaporator before inputting the dehumidifying command signal. The refrigerant compressor is controlled so as to return to the cooling and dehumidifying ability of the compressor. In other words, when the air-conditioning state of the vehicle is in a transient state, for example, in winter, when the temperature in the vehicle interior is rising, fogging is likely to occur in the window glass. Therefore, when transitioning from the transient state to the steady state,
There is a high possibility that the window glass will not become cloudy. Therefore, when the air-conditioning state of the vehicle is in a transient state, when the dehumidification command signal is released, even if the cooling / dehumidifying capacity of the refrigerant evaporator is returned to the cooling / dehumidifying capacity before the input of the dehumidifying command signal, the window glass is not removed. Fog is unlikely to occur.

[0009]

Next, an embodiment of the air conditioner of the present invention will be described with reference to FIGS. FIG. 1 is an overall configuration diagram of the air conditioner, and FIG. 2 is a block diagram illustrating the configuration of the air conditioner. The air-conditioning apparatus 1 of the present embodiment includes a blower duct (ventilation path of the present invention) 2 that guides blown air into a vehicle interior, a blower 3 that generates an airflow toward the vehicle interior in the blower duct 2,
This is an auto air conditioner that includes a refrigerant evaporator 5 and a heater core 6 of a refrigeration cycle 4 disposed in an air duct 2 and that can be automatically controlled by an air conditioner control device 7 to be described later so as to always keep a vehicle interior at a set temperature. . At the upstream end of the air duct 2, there are formed an inside air inlet 8 for circulating the air in the cabin and an outside air inlet 9 for taking in the air outside the cabin, and the inside air inlet 8 and the outside air inlet 9. Is opened and closed by an inside / outside air switching damper 10 that operates according to the selected inside / outside air mode. Blower 3
Consists of a centrifugal fan 3a and a motor 3b that drives the fan 3a to rotate by a voltage applied from the outside. The downstream ends of the blower ducts 2 are branched ducts 11, 1 respectively.
A DEF outlet 14 that discharges blast air toward a window glass (not shown) in the vehicle cabin through FPCs 2 and 13 and a FACE that discharges blast air toward the head and chest of the occupant.
The air outlet 15 communicates with a FOOT air outlet 16 that discharges air toward the feet of the occupant. Each outlet 14 ~
Reference numeral 16 denotes a DEF damper 17, a FACE damper 18, and a FO damper 17 which operate according to the selected outlet mode (described later).
It is opened and closed by the OT damper 19.

The refrigeration cycle 4 is a refrigerant compressor 21 driven by an engine (not shown) of the vehicle via an electromagnetic clutch 20, and sends a high-temperature and high-pressure refrigerant compressed by the refrigerant compressor 21 to a cooling fan 22. A refrigerant condenser 23 which receives and condenses and liquefies a refrigerant, a receiver 24 for temporarily storing the refrigerant guided from the refrigerant condenser 23 and flowing only the liquid refrigerant, and an expansion valve for decompressing and expanding the refrigerant guided from the receiver 24 (expansion means of the present invention) And 25) a refrigerant evaporator 5 for evaporating the refrigerant decompressed by the expansion valve 25 by receiving the air blown by the blower 3 and connected in an annular manner by refrigerant pipes 26. The heater core 6 is connected to a cooling water circuit (not shown) of the engine via a pipe (not shown).
The air passing through the heater core 6 is heated by using the engine cooling water heated by cooling the engine as a heat source. In the air duct 2 in which the heater core 6 is arranged,
A bypass passage 27 bypassing the heater core 6 is formed, and the amount of air passing through the heater core 6 and the bypass passage 27
Is adjusted by the air mix damper 28. A potentiometer 29 (see FIG. 2) for detecting the opening of the air mix damper 28 is connected to the air mix damper 28.

The inside / outside air switching damper 10, the DEF damper 17, the FACE damper 18, the FOOT damper 19, and the air mix damper 28 are each provided with an air conditioner control device 7.
Driven by servo motors 30 to 34 (see FIG. 2) controlled by As shown in FIG. 2, the air conditioner control device 7 includes an internal air temperature sensor 37 that detects an air temperature in the vehicle compartment when a desired temperature is set by a temperature setting switch 36 provided on the air conditioner operation panel 35.
An outside air temperature sensor 38 for detecting outside air temperature, a solar irradiation sensor 39 for detecting the amount of solar radiation entering the vehicle interior, a water temperature sensor 40 for detecting engine cooling water temperature, and an evaporator for detecting air temperature after passing through the refrigerant evaporator 5. Post-temperature sensor 4
1 and various signals from the potentiometer 29 are input to perform a predetermined calculation, and output a control signal for controlling the motor 3b of the blower 3, the electromagnetic clutch 20, and each of the servomotors 30 to 34 based on the calculation result. I do.

Here, the air conditioner operation panel 35 will be described with reference to FIG. 3 (a plan view of the air conditioner operation panel 35). The air conditioner operation panel 35 is provided on a dashboard (not shown) in the front of the passenger compartment.
2. AUTO switch 43, OFF switch 44, inside / outside air changeover switch 45, fan switches 46 to 48, air outlet changeover switches 49 to 52, air conditioner (A / C) switch 53, DEF switch (dehumidification command signal output means of the present invention) ) 54, a rear defogger switch 55 is provided. The temperature setting switch 36 includes an up switch 36a for increasing the set temperature and a down switch 36 for decreasing the set temperature.
By operating these switches 36a and 36b, the set temperature can be set in the range of 18 ° C. to 32 ° C.

The set temperature display section 42 digitally displays the set temperature set by the temperature setting switch 36 (in the figure, 25 ° C. is displayed). AUTO switch 4
Numeral 3 is for outputting an instruction signal to the air conditioner control device 7 to automatically control the motor 3b, the electromagnetic clutch 20, and the servomotors 30 to 34 so that the temperature in the passenger compartment is always at the set temperature. When the AUTO switch 43 is pressed, the display lamp 43a is turned on. OFF
The switch 44 is used to set the voltage applied to the motor 3b to 0 and to stop energizing the electromagnetic clutch 20. When the OFF switch 44 is pressed while the AUTO switch 43 is being pressed, an indicator lamp is displayed. 43a goes out.

The inside / outside air changeover switch 45 sets an outside air mode for designating introduction of outside air and an inside air mode for designating circulation of inside air, and alternately switches between the outside air mode and the inside air mode for each operation. When the outside air mode is set, the display lamp 45a corresponding to the outside air mode is turned on, and the inside / outside air switching damper 10 opens the outside air introduction port 9 and closes the inside air introduction port 8. When the inside air mode is set, the display lamp 45b corresponding to the inside air mode is turned on, and the inside / outside air switching damper 10 opens the inside air inlet 8 and closes the outside air inlet 9. Also, A
When the UTO switch 43 is pressed, the display lamp 45b corresponding to the inside air mode is lit when the opening degree of the inside / outside air switching damper 10 is on the 100% inside air circulation side, and otherwise corresponds to the outside air mode. The display lamp 45a is turned on. The fan switches 46 to 48 are used to set a voltage applied to the motor 3b of the blower 3, and are provided with a Lo switch 46 that minimizes the amount of air blown into the vehicle compartment, a Me switch 47 that achieves an intermediate amount of air, and a maximum amount of air. And a Hi switch 48. When the fan switches 46 to 48 are pressed, the display lamps 46a to 48a corresponding to the respective fan switches 46 to 48 are turned on.

The air outlet changeover switches 49 to 52 are for manually setting the air outlet mode. The air outlet mode is a FACE mode in which air is discharged from the left side to the upper body of the occupant. Bi-level (B / L) mode for discharging air, FOOT mode for discharging blast air toward the occupant's feet, FOOT-D for discharging blast air toward the occupant's feet and window glass
A switch for specifying the EF mode. When the outlet switch 49 to 52 is pressed, each switch 49
The display lamps 49a to 52a corresponding to. The air conditioner switch 53 is for manually designating ON / OFF of the electromagnetic clutch 20. When the electromagnetic clutch 20 is turned on, the display lamp 53a is turned on, and when the electromagnetic clutch 20 is turned off, the display lamp 53a is turned off.

The DEF switch 54 is provided for clearing the fogging generated on the front window glass. By turning on the DEF switch 54, the DEF outlet 14 is automatically selected ( When the electromagnetic clutch 20 is turned on and the refrigeration cycle 4 is operated together with the DEF mode, dehumidified air is discharged from the DEF outlet 14. The DEF switch 54 is repeatedly turned on and off each time the DEF switch 54 is operated.
It can be confirmed by the presence or absence of lighting of 4a. The rear defogger switch 55 is provided in order to clear the fogging of the rear window glass. Like the DEF switch 54, the rear defogger switch 55 is repeatedly turned on and off each time the switch is operated, and the operation status is confirmed by whether or not the display lamp 55a is lit. can do.

Next, a control process of the air conditioner control device 7 when the AUTO switch 43 is pressed will be described with reference to a flowchart shown in FIG. First, in step 100,
From the temperature setting switch 36, the internal temperature sensor 37, the external temperature sensor 38, the solar radiation sensor 39, the water temperature sensor 40, and the post-evaporator temperature sensor 41, the set temperature Tset, the internal temperature Tr, the external temperature Tam, the solar radiation Ts, the engine cooling water temperature, respectively. T
w and post-evaporator temperature Te.

Next, in step 101, step 1
Based on each data input at 00, a target blow-out temperature (hereinafter referred to as TAO) into the vehicle compartment is obtained from the following equation 1.

TAO = Kset × Tset−Kr × Tr−Kam × Tam−Ks × Ts + C where Kset: temperature setting gain, Kr: inside air temperature gain, Kam: outside air temperature gain, Ks: solar radiation gain, C: correction constant It is. In step 102, based on the data input in step 100, the opening degree SW (unit%) of the air mix damper 28 is obtained from the following equation (2).

## EQU00002 ## SW = (TAO-Te) .times.100 / (Tw-Te)

Next, in step 103, step 1
01, the voltage BLW applied to the motor 3b according to the relative characteristics between the TAO previously stored in the air conditioner control device 7 and the voltage applied to the motor 3b.
To determine. Next, in step 104, the TAO
From the TAO stored in the air conditioner control device 7 in advance.
The opening degree SWI of the inside / outside air switching damper 10 is determined according to inside / outside air characteristics indicating the relationship between the opening degree of the inside / outside air switching damper 10 and the opening degree of the inside / outside air switching damper 10. In the present embodiment, when the TAO is low, it is more efficient to cool the inside air having a little lower temperature than to introduce and cool the hot air (outside air) outside the vehicle compartment. In consideration of this, the inside / outside air switching damper 10 is switched to the inside air circulation side, and then, when the inside of the vehicle is cooled to a certain extent and the TAO becomes high, in order to introduce clean outside air into the inside of the vehicle, The inside / outside air characteristics are created so that the air switching damper 10 is switched to the outside air introduction side.

Next, at step 105, the TAO
From the TAO stored in the air conditioner control device 7 in advance.
The outlet mode is determined according to the relative characteristics of the outlet mode. In this embodiment, when the TAO is low, the FACE mode in which the blown air is discharged from the FACE outlet 15 is selected, and as the TAO increases, the blown air is discharged from the FACE outlet 15 and the FOOT outlet 16. The characteristic is created so that the B / L mode to be performed and the FOOT mode in which the blowing air is discharged from the FOOT outlet 16 are selected. Next, in step 106, based on the characteristic indicating the on / off state of the electromagnetic clutch 20 with respect to the deviation between the outside air temperature TAM and the above-mentioned TAO, whether the electromagnetic clutch 20 is turned on in the automatic state (the state in which the AUTO switch 43 is pressed) is determined. Determine the output to turn off. Output value: A / CF (TA
O-TAM)

Next, the operation of this embodiment when the DEF switch 54 is turned on in the automatic state will be described with reference to the flowchart shown in FIG. First, when the DEF switch 54 is turned on (step 20).
0), the DEF counter (CDEF) is updated (step 201). That is, every time the DEF switch 54 is turned on, the value of CDEF is incremented by one. In addition,
In the present embodiment, the initial value of CDEF is 0, and the value of CDEF updated in step 201 is reset when the ignition switch is turned on. Also,
A separate timer may be provided so as to be reset on a daily basis. Then, the updated CDEF and the predetermined value C
By multiplying by 1 (for example, −3 ° C.), the set value DELT
Is determined (step 202). Next, the output value A / C · F obtained in step 106 of the flowchart of FIG.
In step 203, which is the second control means of the present invention, the target temperature TEO after the evaporator after the DEF switch 54 is released is obtained by adding the above DELT to (TAO-TAM). Here, the dehumidifying ability of the refrigeration cycle 4 when the DEF switch 54 is turned off (canceled) to return to the automatic state is determined. In the present embodiment, the dehumidifying ability in the automatic state before the DEF switch 54 is turned on is
This is to increase the dehumidifying capacity in the automatic state after the DEF switch 54 is turned off.

Next, it is determined whether or not the DEF switch 54 has been turned off (step 204). If the DEF switch 54 has been turned off, the TEO obtained in step 203 is set to a predetermined value C.
It is determined whether it is smaller than 2 (for example, 3 ° C.) (Step 205). Note that the predetermined value C2 is the value of the refrigeration cycle 4
Is based on the temperature after the evaporator obtained at the maximum dehumidifying capacity. If TEO is greater than the predetermined value C2 in the determination in step 205, it is determined whether the actual post-evaporator temperature TE is lower than TEO obtained in step 203 (step 206). And TE is T
If it is larger than EO, the electromagnetic clutch 20 is turned on (step 207). That is, the refrigeration cycle 4 is operated until the actual post-evaporator temperature TE decreases to the post-evaporator target temperature TEO after the DEF switch 54 is released.

If it is determined in step 204 that the DEF switch 54 has not been turned off,
If TEO is smaller than the predetermined value C2, TEO is replaced with the predetermined value C2 in step 208, which is the first control means of the present invention. Here, when the DEF switch 54 is not turned off, that is, during the DEF mode, the purpose is to remove the fogging of the window glass. Therefore, since the dehumidifying capacity of the refrigeration cycle 4 is maximized, the TEO is set to the predetermined value C2. And Further, even if TEO is set smaller than the predetermined value C2, the post-evaporator temperature TE obtained at the maximum dehumidifying capacity of the refrigeration cycle 4 does not become smaller than the predetermined value C2, so that TEO is smaller than the predetermined value C2. In this case, TEO is set to a predetermined value C2. Step 20
If TE is smaller than TEO in step 6, the electromagnetic clutch 20 is turned off (step 209). That is, when the actual post-evaporator temperature TE is already lower than TEO, there is no need to turn on the electromagnetic clutch 20 to operate the refrigeration cycle 4, so the electromagnetic clutch 20 is turned off.

As described above, in the present embodiment, when the DEF switch 54 is turned on in the automatic state, the maximum dehumidification capacity of the refrigeration cycle 4 is obtained, and the fogging of the window glass can be removed. After the fogging of the window glass is removed and the DEF switch 54 is turned off, the DEF switch 54 is turned on again to prevent the fogging of the window glass.
Is controlled so that the dehumidifying capacity of the refrigeration cycle 4 becomes higher than the dehumidifying capacity before the DEF switch 54 is turned on. As a result, the number of times the DEF switch 54 is operated is reduced. If the window glass is still fogged, the DEF switch 54 is turned on to remove the fogging of the window glass, and if the DEF switch 54 is turned off, the dehumidifying capacity of the refrigeration cycle 4 is further increased. Controlled. Therefore, as the number of times the DEF switch 54 is operated increases, the dehumidifying capacity of the refrigeration cycle 4 is gradually increased, and is controlled so as to finally reach the maximum dehumidifying capacity.

Next, a second embodiment of the present invention will be described. FIG. 6 is a flowchart showing the operation of the second embodiment. In the present embodiment, when the DEF switch 54 is turned off, it is determined whether the air conditioning state of the vehicle is in a transient state or a steady state, and the dehumidifying capacity of the refrigerant evaporator 5 is determined based on the determination result. Is what you do. Therefore, in this embodiment,
Step 2 of the flowchart shown in FIG. 5 of the first embodiment
Between step 04 and step 205, control is performed to determine the air conditioning state of the vehicle. Hereinafter, control for determining the air-conditioning state of the vehicle will be described based on a flowchart shown in FIG.
Steps 200 to 2 in the flowchart shown in FIG.
04 and steps 205 to 209 are the same as the contents of the flowchart shown in FIG. 5, and a description thereof will be omitted.

If it is determined in step 204 that the DEF switch 54 has been turned off, the absolute value of the difference between the set temperature Tset and the internal air temperature Tr is set in step 300, which is the air-conditioning state determining means of the present invention. It is determined whether it is smaller than α (for example, 5 ° C.). If the result of this determination is YES, since the inside air temperature Tr is close to the set temperature Tset, it is determined that the air-conditioning state of the vehicle is in a steady state and step 205
Proceed to. If the window glass becomes cloudy when the vehicle air condition is in a steady state, the DEF switch 5 is turned on even after the window glass is removed by turning on the DEF switch 54.
By turning off 4, it is highly possible that the window glass is again clouded. The reason will be described below. It is known that fogging of window glass occurs when the window glass temperature is equal to or lower than the dew point temperature of the vehicle interior air. In addition, the window glass temperature rises as the temperature inside the vehicle interior rises. Therefore, in a transient state in which the window glass temperature is changing, the window glass often clears even if the window glass becomes cloudy if the window glass temperature rises and stabilizes in a steady state even if the window glass becomes cloudy. On the other hand, under steady conditions, that is, when the window glass becomes cloudy when the temperature of the window glass has risen completely and is stable, the window glass always becomes cloudy. There is. Therefore, when the air-conditioning state determining means (step 300) determines that the air-conditioning state of the vehicle is in a steady state, the dehumidifying capacity of the refrigeration cycle 4 is changed to the value before the DEF switch 54 is turned on, as in the first embodiment. The energization control of the electromagnetic clutch 20 is performed so as to be higher than the dehumidifying ability of the electromagnetic clutch 20.
Thereby, even if the DEF switch 54 is turned off, it is possible to prevent the window glass from fogging again.

If the decision result in the step 300 is NO,
Since the difference between the set temperature Tset and the internal temperature Tr is large, that is, the internal temperature Tr is rising, it is determined that the air conditioning state of the vehicle is in a transitional state, and the routine proceeds to step 301. In step 301 (third control means of the present invention), the post-evaporator target temperature TEO is set to a control value before the DEF switch 54 is turned on, and then the process proceeds to step 205. When the air-conditioning state of the vehicle is in a transient state, the window glass tends to be fogged when the temperature in the vehicle interior is rising, in winter, when the vehicle interior temperature is rising. Therefore, when the transition from the transient state to the steady state occurs, there is a high possibility that the window glass will not be fogged. Therefore, when the air-conditioning state of the vehicle is in a transient state, the window glass may be fogged even if the dehumidifying capacity of the refrigeration cycle 4 is returned to the dehumidifying capacity before the DEF switch 54 is turned on when the DEF switch 54 is turned off. The nature is low. Therefore, if the air-conditioning state determining means (step 300) determines that the air-conditioning state of the vehicle is in a transient state, step 301 is executed to determine the dehumidifying capacity of the refrigeration cycle 4 before the DEF switch 54 is turned on. The energization control of the electromagnetic clutch 20 is performed so as to return to the dehumidifying ability. Thereby, when the air conditioning state of the vehicle is changed from the transient state to the steady state and the window glass becomes less cloudy, the DEF switch 54 is turned off, and the dehumidifying capacity of the refrigeration cycle 4 is unnecessarily increased by consumption. An increase in power can be prevented. In the second embodiment, the set temperature T
The absolute value of the difference between set and the internal temperature Tr was compared with the set value α. However, when the difference between the set temperature Tset and the internal temperature Tr is a negative value, that is, the internal temperature Tr is larger than the set temperature Tset. In this case, since the cooling mode is set, the set temperature T
The difference between set and the internal temperature Tr may be compared with a set value α.

Next, a third embodiment of the present invention will be described. FIG. 7 is a flowchart showing the operation of the third embodiment. In the second embodiment, the absolute value of the difference between the set temperature Tset and the internal temperature Tr is compared with the set value α to determine whether the air conditioning state of the vehicle is in the transient state or the steady state. In the third embodiment, it is determined whether the air-conditioning state of the vehicle is in a transient state or a steady state based on an elapsed time since an ignition switch (a signal instructing activation of the refrigerant compressor) is turned on. Therefore, in the present embodiment, the processing of step 300 in the flowchart shown in FIG. 6 is changed to the processing of step 310 described below, and control for determining the air conditioning state of the vehicle is performed. Note that the processing contents other than step 310 are the same as the processing contents shown in FIG. 6, and a description thereof will be omitted. In step 310, step 20
When it is determined in step 4 that the DEF switch 54 has been turned off, it is determined whether a predetermined time β (for example, 10 minutes) has elapsed since the ignition switch was turned on. If the determination result of step 310 is YES,
At the time when the DEF switch 54 is turned off, since a sufficient time has elapsed since the ignition switch was turned on, it is determined that the air conditioning state of the vehicle is in a steady state. If the result of the determination in step 310 is NO, sufficient time has not elapsed since the ignition switch was turned on at the time when the DEF switch 54 was turned off. In other words, after the window glass is clouded and the DEF switch 54 is turned on, D
This means that the EF switch 54 has been turned off. Therefore, in this case, it is determined that the air conditioning state of the vehicle is in a transient state. With the above control, it is determined whether the air-conditioning state of the vehicle is a steady state or a transient state, and the energization control of the electromagnetic clutch 20 is performed according to the air-conditioning state.

Next, a fourth embodiment of the present invention will be described. FIG. 8 is a flowchart showing the operation of the fourth embodiment. In the above-described second and third embodiments, the control example for determining the air-conditioning state of the vehicle when the DEF switch 54 is turned off has been described.
4 is a control example for determining the air-conditioning state of the vehicle when the vehicle is turned on. Hereinafter, a control example of the present embodiment will be described based on a flowchart shown in FIG. Note that, in the processing contents of the flowchart shown in FIG. 8, the same processing contents as those in the flowchart shown in FIG. Step 20 is performed when the DEF switch 54 is turned on.
After executing step 1, it is determined whether or not the absolute value of the difference between the set temperature Tset and the internal temperature Tr is smaller than a set value α (for example, 5 ° C.) (step 300).

If the decision result in the step 300 is YES, "1" is set in the FLAG counter (step 32).
0) and proceed to step 202. Step 300
Is "NO", the FLAG counter is set to "0".
Is set (step 330), and the routine proceeds to step 202. After performing steps 202 and 203, step 2
If it is determined in step 04 that the DEF switch 54 has been turned off, step 3 constituting the air-conditioning state determining means of the present invention
At 40, it is determined whether or not '1' is set in the FLAG counter. If the determination result of step 340 is Y
In the case of ES, it indicates that the inside air temperature Tr is close to the set temperature Tset (the temperature difference is within 5 ° C.). As a result, the energization control of the electromagnetic clutch 20 is performed so that the dehumidifying capacity of the refrigeration cycle 4 becomes higher than the dehumidifying capacity before the DEF switch 54 is turned on. Glass can be prevented from fogging.

If the decision result in the step 340 is NO, it indicates that the difference between the set temperature Tset and the internal temperature Tr is large, that is, the internal temperature Tr is increasing, and the air conditioning state of the vehicle is in a transient state. It proceeds to step 301. In step 301 (third control means of the present invention), the evaporator target temperature TEO is set to a control value before the DEF switch 54 is turned on. Thereafter, the process proceeds to step 205. As a result, the energization control of the electromagnetic clutch 20 is performed so as to return the dehumidifying capacity of the refrigeration cycle 4 to the dehumidifying capacity before the DEF switch 54 is turned on, so that the DEF switch 54 is turned off unnecessarily. It is possible to prevent the dehumidification capacity of the refrigeration cycle 4 from being increased, thereby preventing an increase in power consumption. Note that the processing content of step 300 of the present embodiment may be replaced with the processing content of step 310 described in the third embodiment. That is, after executing step 201, in step 310, it is determined whether or not a predetermined time β (for example, 10 minutes) has elapsed since the ignition switch was turned on. If the determination result is YES, the process proceeds to step 320. The process proceeds to step 330 if the determination result is NO.

According to the air conditioner of the present invention, when the dehumidification command signal is released, the cooling dehumidification capacity of the refrigerant evaporator is made larger than the cooling dehumidification capacity before the dehumidification command signal is input. By performing the control of the refrigerant compressor, it is possible to reduce the trouble of the switch operation in eliminating the fogging of the window glass. Further, it is not necessary to always operate the refrigerant compressor with the maximum dehumidifying capacity, and power saving of the refrigerant compressor can be achieved.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of an air conditioner of the present embodiment.

FIG. 2 is a block diagram illustrating a configuration of an air conditioner of the present embodiment.

FIG. 3 is a plan view of an air conditioner operation panel according to the embodiment.

FIG. 4 is a flowchart showing the operation of the air conditioner control device.

FIG. 5 is a flowchart showing the operation of the embodiment when the DEF switch is pressed.

FIG. 6 is a flowchart showing an operation of the air conditioner according to the second embodiment.

FIG. 7 is a flowchart showing the operation of the air conditioner according to the third embodiment.

FIG. 8 is a flowchart showing an operation of the air conditioner according to the fourth embodiment.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 air conditioner 2 ventilation duct (ventilation path) 4 refrigeration cycle 5 refrigerant evaporator 7 air conditioner control device (first, second, third control means,
Air-conditioning state determining means) 21 refrigerant compressor 23 refrigerant condenser 25 expansion valve (expansion means) 54 DEF switch (dehumidification command signal output means)

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yuji Ito 1-1-1, Showa-cho, Kariya-shi, Aichi Japan Inside Denso Co., Ltd. (72) Inventor Katsuhiko Samugawa 1-1-1, Showa-cho, Kariya-shi, Aichi Japan Nihon Denso Co., Ltd. (72) Inventor Sugi Hikari 1-1-1, Showa-cho, Kariya-shi, Aichi Japan Inside Denso Co., Ltd. (58) Field surveyed (Int. Cl. ⁷ , DB name) B60H 1/32 B60H 3/00

Claims (2)

(57) [Claims] 1. A refrigerating cycle comprising a ventilation path for introducing air into a vehicle interior, a refrigerant compressor, a refrigerant condenser and expansion means, wherein the cooling and dehumidifying capacity is adjusted by the operation of the refrigerant compressor. A refrigerant evaporator that cools and dehumidifies the air of the air; a dehumidification command signal output unit that outputs a dehumidification command signal that indicates that it is necessary to dehumidify the cabin by a driver's manual operation; and the dehumidification command signal is input. And first control means for controlling the refrigerant compressor so as to increase the cooling and dehumidifying capacity of the refrigerant evaporator, and performs economy control for reducing the cooling and dehumidifying capacity of the refrigerant evaporator as necessary. In the air conditioner, when the input state of the dehumidification command signal is released, the cooling and dehumidifying capacity of the refrigerant evaporator is made larger than the cooling and dehumidifying capacity before the dehumidification command signal is input. An air conditioning apparatus characterized in that it comprises a second control means for controlling the urchin the refrigerant compressor. 2. A refrigeration cycle comprising an air passage for guiding air into the vehicle interior, a refrigerant compressor, a refrigerant condenser, and expansion means, wherein the operation of the refrigerant compressor regulates the cooling and dehumidifying capacity. A refrigerant evaporator that cools and dehumidifies the air of the air; a dehumidification command signal output unit that outputs a dehumidification command signal that indicates that it is necessary to dehumidify the cabin by a driver's manual operation; and the dehumidification command signal is input. And first control means for controlling the refrigerant compressor so as to increase the cooling and dehumidifying capacity of the refrigerant evaporator, and performs economy control for reducing the cooling and dehumidifying capacity of the refrigerant evaporator as necessary. In the air conditioner, an air-conditioning state determining unit that determines whether the air-conditioning state of the vehicle is in a transient state or a steady state, and the air-conditioning state of the vehicle is in a steady state by the air-conditioning state determining means. If it is determined that the input state of the dehumidification command signal is canceled, the cooling dehumidification capacity of the refrigerant evaporator is set to be larger than the cooling dehumidification capacity before the dehumidification command signal is input. The second controlling the refrigerant compressor
When the air-conditioning state of the vehicle is determined to be in a transitional state by the air-conditioning state determining means, the input / output state of the dehumidification command signal is released and the cooling / dehumidifying capacity of the refrigerant evaporator is reduced. And a third control unit for controlling the refrigerant compressor so as to return to the cooling / dehumidifying capacity before the dehumidification command signal is input.