JP2005254862A - Air conditioner for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent unpleasant humid air from an evaporator from blowing into a cabin when the evaporator is wet. <P>SOLUTION: When it is detected that the evaporator is wet based on a dew-point temperature during stopping of an air blower of the air conditioner, a door for switching inside and outside air is controlled to be in an inside air mode when the vehicle is in the traveling state. That is, the air flow by the outside air introduced into a ventilation duct in traveling in the outside air mode takes moisture out of the wet evaporator, and the humid air flow including an unpleasant odor is prevented from flowing into the cabin by changing the mode to the inside air mode. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a vehicle air conditioner.

2. Description of the Related Art Conventionally, there is a vehicle air conditioner that calculates a target blowing temperature and controls a blower air volume in a stepless manner according to the target blowing temperature, a so-called auto air conditioner (see, for example, Patent Document 1).
JP 58-26618 A

  Immediately after the blower of the air conditioner and the refrigerant compressor are stopped, the evaporator, which is a cooling heat exchanger, may condense, that is, the evaporator may be wet depending on the temperature and humidity state of the air. In such a state, for example, when the vehicle is running in the outside air mode, an air flow is generated around the evaporator due to the introduced outside air even when the blower is stopped, and air that has taken moisture away from the wet evaporator is blown. It will be blown out from the exit into the passenger compartment.

  In this case, the occupant is exposed to the wind blown from the outlet, that is, the humid air from the evaporator and the unpleasant wind due to the odor contained in the moisture. No measures were taken.

  The present invention has been made in view of the above points, and it is an object of the present invention to prevent damp and unpleasant wind from an evaporator from being blown into a vehicle interior when the evaporator is wet.

  In order to achieve the above object, the invention described in claim 1 includes a ventilation duct (2) for sending air toward the passenger compartment, an outside air mode for introducing outside air into the ventilation duct, and a vehicle in the ventilation duct. An inside / outside air switching door (6) for switching between an inside air mode for introducing indoor air, a blower (8) for generating an air flow toward the passenger compartment in the ventilation duct, and the ventilation duct to cool the air flow In an air conditioner for a vehicle having an evaporator (9) that performs, an evaporator wetness detecting means (S210) that detects the wet state of the evaporator, and when the wet state of the evaporator is detected, the inside / outside air switching door is set to the inside air mode. Switching control means (S240).

  According to the present invention, when the evaporator is in a wet state, the door for switching the inside / outside air is set to the inside air mode for introducing the inside air, so that the outside air is not introduced into the evaporator. At this time, the moisture of the evaporator is absorbed and blown out into the passenger compartment. Therefore, it is possible to prevent the unpleasant wind containing the moisture of the wet evaporator from hitting the occupant and to improve the comfort of the occupant.

  The invention according to claim 2 further includes traveling state determination means (S230) for determining whether or not the vehicle is in a traveling state, and the switching control means determines that the traveling state means is in the traveling state. In this case, the inside / outside air switching door is set to the inside air mode.

  According to the present invention, when the evaporator is wet and the vehicle is running, the inside / outside air switching door is set to the inside air mode, so that outside air is introduced into the ventilation duct as the vehicle runs. Therefore, when the outside air hits the wet evaporator, the moisture of the evaporator is absorbed and blown out into the passenger compartment. Therefore, it is possible to prevent the unpleasant wind containing the moisture of the wet evaporator from hitting the occupant and to improve the comfort of the occupant.

  The invention according to claim 3 is characterized in that when the blower is in a stopped state, the switching control means sets the inside / outside air switching door to the inside air mode.

  According to this invention, since the blower is stopped and the inside / outside air switching door is set to the inside air mode, no air flow is generated in the ventilation duct, and therefore, an air flow passing through the wet evaporator is also generated. do not do. Thus, since the air flow does not hit the evaporator, the air flow hits the wet evaporator and absorbs the moisture of the evaporator and is not blown into the vehicle interior. Therefore, it is possible to prevent the unpleasant wind containing the moisture of the wet evaporator from hitting the occupant and to improve the comfort of the occupant.

  According to a fourth aspect of the present invention, there is provided a determination means (S60) for determining that the air conditioning thermal load for maintaining the temperature in the passenger compartment at a set temperature is in a minimum range of a predetermined amount or less, and the air conditioning thermal load is in a minimum range And a blower stopping means (S90) for automatically stopping the blower when it is determined that the switching control means sets the inside / outside air switching door to the inside air mode according to the magnitude of the air conditioning heat load. And

  In this invention, “the air conditioning heat load for maintaining the temperature in the vehicle interior at the set temperature” corresponds to the amount of heat for heating or cooling the air blown into the vehicle interior in order to maintain the vehicle interior temperature at the set temperature. When the air-conditioning heat load is in a minimum range equal to or less than a predetermined amount, the vehicle interior temperature is maintained in the vicinity of a set temperature that is comfortable for the passenger.

  Therefore, by determining that the air-conditioning heat load is in the minimum range equal to or less than a predetermined amount and automatically stopping the blower, the operation noise of the blower is eliminated and the passenger compartment is not disturbed by the manual operation. It can be a quiet environment.

  Moreover, since the inside air mode is set according to the heat load of the air conditioning, uncomfortable winds including wet evaporator moisture are prevented from blowing into the passenger compartment and hitting the occupant, thereby improving the comfort of the occupant. it can.

  Furthermore, as described in claim 5, the compressor (11) of the refrigeration cycle that creates the cooling state of the evaporator, and the compressor that automatically stops the compressor when it is determined that the air conditioning heat load is in the minimum range If the stop means (S100) is provided, the condition of the air-conditioning heat load can be determined and the compressor of the refrigeration cycle can be automatically stopped in conjunction with the automatic stop of the blower, thus reducing the power consumption of the blower. In addition, the driving power of the compressor can be reduced.

  In addition, since the compressor is stopped when the air conditioning heat load is at a minimum range, the evaporator in the refrigeration cycle is wet and moisture is easily absorbed by the air flow in the ventilation duct. Therefore, if the outside air is not introduced as the inside air mode at this time, an unpleasant wind containing the moisture of the wet evaporator is prevented from being blown into the passenger compartment and hitting the occupant, thereby improving the comfort of the occupant. it can.

  According to the sixth aspect of the present invention, the temperature adjusting means (17) for adjusting the temperature of the air blown into the passenger compartment, and the temperature adjusting means so that the temperature of the air blown into the passenger compartment becomes the target outlet temperature (TAO). It is characterized by comprising temperature control means (S40, S50) for automatic control and blower control means (S70) for automatically controlling the air volume of the blower according to the target blowing temperature when the air conditioning heat load is outside the minimum range. To do.

  According to this, when the air-conditioning heat load is outside the minimum range, the air volume of the blower is automatically controlled according to the target blowing temperature, whereby the vehicle interior blowing volume can be automatically controlled according to the target blowing temperature. In such an automatic air volume control, unpleasant winds including wet evaporator moisture are prevented from being blown into the passenger compartment and hitting the occupant, and passenger comfort can be improved.

  As described in claim 7, when the air conditioning heat load is in the minimum range, the switching control means sets the inside / outside air switching door to the inside air mode so that the outside air introduced into the ventilation duct gets wet. When hitting the evaporator, moisture is absorbed from the evaporator, and unpleasant wind containing the moisture is prevented from being blown into the passenger compartment and hitting the occupant, thereby improving the comfort of the occupant.

  Alternatively, as described in claim 8, the blower control means sets the blower air volume to the minimum air volume when the air conditioning heat load is outside the minimum range, and the switching control means sets the air conditioning heat load to the minimum range and the predetermined range. In this case, the inside / outside air switching door can be set to the inside air mode.

  The determination means can determine that the air-conditioning heat load is in the minimum range based on the target blowing temperature as described in claim 9, and further, the setting temperature can be set as described in claim 10. It is also possible to determine that the air conditioning heat load is in the minimum range based on at least one of the vehicle interior temperature, the outside air temperature, and the amount of solar radiation.

  The invention according to claim 11 is a temperature / humidity detecting means (31, 32, 33) for detecting the temperature and humidity of the air introduced into the ventilation duct, and a post-evaporation temperature sensor for detecting the air temperature immediately after passing through the evaporator ( 35) and the wetness detecting means calculates the dew point temperature of the air according to the detected temperature and humidity of the air, and the dew point temperature is higher than the temperature detected by the post-evaporation temperature sensor. And determining that the evaporator is in a wet state.

  According to this invention, by comparing the air introduced into the ventilation duct, that is, the dew point of the outside air in the case of the outside air mode, or the dew point of the inside air in the case of the inside air mode, and the air temperature immediately after passing through the evaporator. Since it is determined that the evaporator is in a wet state, the wet state of the evaporator can be detected with a simple configuration.

  Further, as described in claim 12, an outside air temperature sensor (31) for detecting the temperature of outside air and a post-evaporation temperature sensor (35) for detecting the air temperature immediately after passing through the evaporator, The evaporator can be determined to be in a wet state based on the detected outside air temperature and the temperature detected by the post-evaporation temperature sensor. Thereby, when the outside air temperature is a temperature in the vicinity of the set temperature that is comfortable for passengers in the passenger compartment, the wet state of the evaporator can be easily detected without using humidity detecting means.

  Alternatively, as described in claim 13, the evaporator wetness detecting means can easily detect the evaporator wet state even by determining that the evaporator is in a wet state within a predetermined time from the stop of the blower.

  Furthermore, as described in claim 14, an evaporator humidity sensor (38) for detecting the humidity in the vicinity of the evaporator and a humidity sensor (33) for detecting the humidity of the air introduced into the ventilation duct are provided. The wetness detection means can determine that the evaporator is wet by comparing the detected humidity in the vicinity of the evaporator and the detected humidity of the air introduced into the ventilation duct.

  In addition, the code | symbol in the bracket | parenthesis of each said means shows the correspondence with the specific means as described in embodiment mentioned later.

(First embodiment)
FIG. 1 shows an outline of the overall configuration of the first embodiment. A vehicle air conditioner includes an indoor air conditioning unit 1 disposed inside an instrument panel (not shown) at the foremost part of a vehicle interior. Yes. This indoor air-conditioning unit 1 has a case 2, and an air passage through which air is blown toward the vehicle interior is formed inside the case 2, and constitutes the ventilation duct 2 of the present invention.

  An inside / outside air switching box 5 having an inside air introduction port 3 and an outside air introduction port 4 is arranged at the most upstream part of the ventilation duct 2. Inside / outside air switching box 5, an inside / outside air switching door 6 as inside / outside air switching means is rotatably arranged.

  The inside / outside air switching door 6 is driven by a servo motor 7, and an inside air mode for introducing inside air (vehicle compartment air) from the inside air introduction port 3 and an outside air mode for introducing outside air (vehicle compartment outside air) from the outside air introduction port 4. And switch.

  On the downstream side of the inside / outside air switching box 5, an electric blower 8 that generates an air flow toward the vehicle interior is disposed. The blower 8 is configured to drive a centrifugal blower fan 8a by a motor 8b. An evaporator 9 that cools the air flowing in the case 2 is disposed on the downstream side of the blower 8. The evaporator 9 is a cooling heat exchanger that cools the air blown from the blower 8, and is one of the elements constituting the refrigeration cycle apparatus 10.

  Note that the refrigeration cycle apparatus 10 is a well-known one that is configured so that refrigerant circulates from the discharge side of the compressor 11 to the evaporator 9 via the condenser 12, the liquid receiver 13, and the expansion valve 14 that constitutes the pressure reducing means. It is. Outdoor air (cooling air) is blown to the condenser 12 by an electric cooling fan 12a.

  In the refrigeration cycle apparatus 10, the compressor 11 is driven by a vehicle engine (not shown) via an electromagnetic clutch 11a. Therefore, the operation of the compressor 11 can be intermittently controlled by the energization of the electromagnetic clutch 11a. In addition, the evaporator 9 cools the blown air when the low-temperature and low-pressure gas-liquid two-phase refrigerant that has been decompressed by the expansion valve 14 absorbs heat from the blown air of the blower 8 and evaporates.

  On the other hand, in the indoor air conditioning unit 1, a heater core 15 that heats the air flowing in the case 2 is disposed on the downstream side of the evaporator 9. The heater core 15 is a heating heat exchanger that heats the air (cold air) that has passed through the evaporator 9 using warm water (engine cooling water) of the vehicle engine as a heat source. A bypass passage 16 is formed on the side of the heater core 15, and the bypass air of the heater core 15 flows through the bypass passage 16.

  Between the evaporator 9 and the heater core 15, an air mix door 17 serving as a temperature adjusting means is rotatably arranged. The air mix door 17 is driven by a servo motor 18 so that its rotational position (opening) can be continuously adjusted.

  The ratio of the amount of air passing through the heater core 15 (warm air amount) and the amount of air passing through the bypass passage 16 and bypassing the heater core 15 (cold air amount) is adjusted by the opening degree of the air mix door 17. The temperature of the air blown into the room is adjusted.

  At the most downstream part of the air passage of the case 2, a defroster outlet 19 for blowing conditioned air toward the front window glass W of the vehicle, a face outlet 20 for blowing conditioned air toward the face of the occupant, A total of three types of air outlets 21 are provided, which are foot outlets 21 for blowing air-conditioned air toward the feet of passengers.

  A defroster door 22, a face door 23, and a foot door 24 are rotatably disposed upstream of the air outlets 19 to 21. The doors 22 to 24 are opened and closed by a common servo motor 25 via a link mechanism (not shown).

  Next, the outline of the electric control unit according to the present embodiment will be described. The air conditioning control device 30 includes a known microcomputer including a CPU, a ROM, a RAM, and the like and peripheral circuits thereof. The air conditioning control device 30 stores a control program for air conditioning control in its ROM, and performs various calculations and processes based on the control program.

  Sensor detection signals are input from the sensor groups 31 to 37 to the input side of the air conditioning control device 30, and various operation signals are input from the air conditioning panel 40 disposed near the instrument panel (not shown) in the front of the vehicle interior. Is done.

  Specifically, the sensor group includes an outside air temperature sensor 31 that detects an outside air temperature (outside temperature of the passenger compartment) Tam, an inside air temperature sensor 32 that detects an inside air temperature (vehicle interior temperature) Tr, and the relative humidity ψ of the inside air and the outside air. Humidity sensor (inside air humidity sensor, outside air humidity sensor) 33 to be detected, solar radiation sensor 34 to detect the amount of solar radiation Ts entering the vehicle interior, evaporator air temperature (hereinafter referred to as post-evaporation temperature) disposed in the air blowing portion of the evaporator 9 A post-evaporation temperature sensor 35 for detecting Te, a water temperature sensor 36 for detecting the temperature Tw of hot water (engine cooling water) flowing into the heater core 15, a vehicle speed sensor 37 for detecting the vehicle speed V, and the like are provided.

  Among these, the humidity sensor 33 is arranged in the air duct 2 at the upstream side of the air flow of the blower fan 8a, for example, the suction port of the blower fan 8a. Thereby, the relative humidity of the inside air can be detected in the inside air mode, and the relative humidity of the outside air can be detected in the outside air mode.

  Further, the air conditioning panel 40 is provided with switches 41 to 47 shown in FIG. 2 as various operation switches. The temperature setting switch 41 outputs a signal of a set temperature in the passenger compartment, and includes an operation knob 41a for increasing the set temperature, an operation knob 41b for decreasing the set temperature, and a set temperature display portion 41c.

  The blowing mode switch 42 outputs signals for manually setting various blowing modes set by the blowing mode doors 22 to 24, and includes a face mode setting knob 42a, a bi-level mode setting knob 42b, and a foot mode setting knob. 42c, a foot defroster mode setting knob 42d, and a defroster mode setting knob 42e.

  The inside / outside air changeover switch 43 outputs a signal for manually setting the inside air mode and the outside air mode by the inside / outside air switching door 6, and includes an inside air mode setting knob 43a and an outside air mode setting knob 43b.

  The air conditioner switch 44 outputs an operation command signal for the compressor 11 (ON signal for the electromagnetic clutch 11a). The economy switch 45 outputs a signal for raising the target post-evaporation temperature TEO to lower the operating rate of the compressor 11.

  The blower operation switch 46 outputs a signal for manually setting the air volume switching of the blower 8, and includes an OFF knob 46a for stopping the blower 8, an operation knob 46b for low air volume, an operation knob 46c for the first medium air volume, An operation knob 46d for a second medium air volume that is a predetermined amount larger than the first medium air volume, and an operation knob 46e for a large air volume are provided.

  The auto switch 47 outputs a command signal for the air conditioning automatic control state. When the auto switch 47 is turned on, the electromagnetic clutch 11a is energized to operate the compressor 11 even when the air conditioner switch 44 is turned off. In addition, the operation of various air conditioners is automatically controlled.

  On the output side of the air conditioning control device 30, there are an electromagnetic clutch 11a of the compressor 11, servo motors 7, 18, 25 serving as electric drive means for each device, a motor 8b of the blower 8, a motor 12b of the condenser cooling fan 12a, and the like. The operation of these devices is controlled by the output signal of the air conditioning control device 30.

  Next, the operation of this embodiment in the above configuration will be described. First, the outline of the operation of the indoor air conditioning unit 1 will be described. By operating the blower 8, the air introduced from the inside air introduction port 3 or the outside air introduction port 4 is blown through the case 2 toward the vehicle interior. . Also, the refrigerant is circulated in the refrigeration cycle apparatus 10 by energizing the electromagnetic clutch 11a to bring the electromagnetic clutch 11a into a connected state and driving the compressor 11 with a vehicle engine.

  The blown air of the blower 8 first passes through the evaporator 9 to be cooled and dehumidified, and this cold air then passes through the heater core 15 and the bypass passage 16 according to the rotation position (opening degree) of the air mix door 17. The flow is divided into The flow passing through the heater core 15 is heated to become hot air, and the flow passing through the bypass passage 16 remains cold air.

  Therefore, the ratio of the amount of air passing through the heater core 15 (warm air amount) and the amount of air passing through the bypass passage 16 (cold air amount) is adjusted by the opening degree of the air mix door 17, and thereby the air blown into the vehicle interior The temperature can be adjusted. And this temperature-controlled conditioned air is supplied from any one or more of the defroster air outlet 19, the face air outlet 20 and the foot air outlet 21 located at the most downstream part of the air passage of the case 2. It blows out into the passenger compartment and performs air conditioning in the passenger compartment and fogging prevention of the front window glass W of the vehicle.

  Next, automatic control of air conditioning in the present embodiment will be described with reference to FIG. FIG. 3 is a flowchart of an air conditioning control routine executed by the microcomputer of the air conditioning control device 30. This air conditioning control routine starts when the auto switch 47 is turned on. First, in step S10, the detection signals of the sensor groups 31 to 37 are detected. Various operation signals from the air conditioning panel 40 are read.

  Next, the target blowing temperature TAO of the blowing air into the vehicle interior is calculated in step S20. This target blowout temperature TAO is a vehicle cabin blowout air temperature required to maintain the vehicle cabin temperature at the set temperature Tset set by the occupant by the temperature setting switch 41 of the air conditioning panel 40 regardless of the air conditioning thermal load fluctuation. This TAO is calculated by the following formula (1) based on the set temperature Tset, the outside air temperature Tam, the inside air temperature Tr, and the solar radiation amount Ts.

TAO = Kset × Tset−Kr × Tr−Kam × Tam−Ks × Ts + C (1)
Where Kset, Kr, Kam, Ks: Control gain
C: Correction constant Next, in step S30, a target post-evaporation temperature TEO is calculated. Here, the target post-evaporation temperature TEO is a control value determined mainly for controlling the temperature of the air blown into the vehicle interior, controlling fogging of the vehicle front window glass W, controlling the power saving (economy) of the compressor 11, and the like. Thus, it is calculated according to the target blowout temperature TAO, the outside air temperature Tam, and the like.

  Specifically, the temperature is decreased between the first target post-evaporation temperature TEOa having a characteristic that decreases in accordance with the decrease in the target outlet temperature TAO, the low temperature range and the high temperature range of the outside air temperature Tam, and the intermediate temperature range of the outside air temperature Tam. Of the second target post-evaporation temperature TEOb having the characteristic of increasing at a lower value, the lower one is finally determined as the target post-evaporation temperature TEO.

  Note that the third target post-evaporation temperature TEOc determined according to the vehicle interior humidity for the vehicle interior humidity control is calculated, and the first, second, and third target post-evaporation temperatures TEOa, TEOb, and TEOc are the most. A low temperature may be finally determined as the target post-evaporation temperature TEO.

  Next, in step S40, the target opening degree SW of the air mix door 17 is changed to the target outlet temperature TAO, the post-evaporation temperature Te detected by the post-evaporation temperature sensor 35, and the hot water temperature Tw detected by the water temperature sensor 44. Is calculated by the following equation (2).

SW = {(TAO−Te) / (Tw−Te)} × 100 (%) (2)
Next, in step S50, the air mix door 17 is driven and controlled by the servo motor 18 so that the actual opening degree of the air mix door 17 becomes the target opening degree SW. Thus, the vehicle interior outlet temperature is controlled to become the target outlet temperature TAO, and the vehicle interior temperature Tr is maintained at the set temperature Tset.

  SW = 0 (%) is the maximum cooling position of the air mix door 17, and the bypass passage 16 is fully opened and the ventilation path on the heater core 15 side is fully closed. On the other hand, SW = 100 (%) is the maximum heating position of the air mix door 17 and fully closes the bypass passage 16 and fully opens the ventilation path on the heater core 15 side.

  Next, in step S60, it is determined whether the target blowing temperature TAO is in a predetermined intermediate temperature range near the set temperature Tset. Specifically, the predetermined intermediate temperature range in the vicinity of the set temperature Tset is 18 ° C to 34 ° C. The set temperature Tset is a temperature at which the passenger feels comfortable, and is usually set to a temperature around 25 ° C. Therefore, it can be said that this intermediate temperature range of TAO = 18 ° C. to 34 ° C. is a temperature range in which the air conditioning heat load of the indoor air conditioning unit 1 is minimized. Here, the air conditioning heat load of the indoor air conditioning unit 1 refers to the amount of heat that cools or heats the intake air of the indoor air conditioning unit 1 in order to maintain the vehicle interior temperature Tr at the set temperature Tset.

  When the air conditioner is started, for example, when the air conditioner is started in the summer, the interior of the vehicle interior may become as high as 50 ° C. or higher. Therefore, the target blowing temperature TAO is calculated as a low temperature of −30 ° C. or lower when the air conditioner starts. . For this reason, the determination in step S60 is NO.

  In addition, since the interior of the passenger compartment becomes a low temperature of 0 ° C. or lower when heating is started in winter, the target blowing temperature TAO is calculated as a high temperature of 90 ° C. or higher when heating is started. For this reason, the determination in step S60 is NO.

  Thus, at the time of cooling start-up immediately after the start of the air conditioner and at the time of heating start-up, the air-conditioning heat load of the indoor air-conditioning unit 1 becomes very large, and the target blowout temperature TAO is set as a high temperature or a low temperature far from the set temperature Tset. Since it is calculated, the determination in step S60 is NO and the process proceeds to step S70.

  In step S70, the blower 8 is turned on (ON), and the air volume of the blower 8 is automatically controlled in accordance with the change in the target blowing temperature TAO.

  This air volume control will be described in detail with reference to FIG. 4. Since the target blowing temperature TAO is normally calculated as a temperature lower than the first predetermined temperature T1 (for example, −30 ° C.) in FIG. The voltage applied to the drive motor 8b of the blower 8 is maximized, and the air volume of the blower 8 is set to the maximum air volume (Hi).

  And the target blowing temperature TAO rises as cooling of a vehicle interior advances and vehicle interior temperature (inside temperature) Tr falls. When the target blowing temperature TAO rises to the first predetermined temperature T1 or higher, the applied voltage to the drive motor 8b of the blower 8 is continuously lowered to continuously reduce the air volume of the blower 8.

  When the target blowing temperature TAO rises to a second predetermined temperature T2 (for example, 8 ° C.), the air volume of the blower 8 is reduced to the minimum air volume (Lo).

  On the other hand, since the target blowing temperature TAO is normally calculated as a temperature higher than the sixth predetermined temperature T6 (eg, 90 ° C.) in FIG. 4 at the start of heating in winter, the applied voltage to the drive motor 8b of the blower 8 is maximized. Thus, the air volume of the blower 8 is set to the maximum air volume (Hi).

  In FIG. 4, the maximum air volume (Hi) on the low temperature side (cooling side) of the target blowing temperature TAO and the maximum air volume (Hi) on the high temperature side (heating side) of the target blowing temperature TAO are shown as the same value. In general, since the required air volume during maximum cooling is greater than the required air volume during maximum heating, the maximum air volume (Hi) on the high temperature side (heating side) of the target blowing temperature TAO is actually set to the low temperature side of the target blowing temperature TAO. A predetermined amount smaller than the maximum air volume (Hi) on the (cooling side) is set.

  Then, as the heating of the vehicle interior proceeds and the vehicle interior temperature (inside air temperature) Tr increases, the target blowing temperature TAO decreases. When the target blowing temperature TAO falls below the sixth predetermined temperature T6, the applied voltage to the drive motor 8b of the blower 8 is continuously lowered to continuously reduce the air volume of the blower 8.

  When the target blowing temperature TAO decreases to the fifth predetermined temperature T5 (for example, 44 ° C.), the air volume of the blower 8 is decreased to the minimum air volume (Lo).

  In FIG. 3, in the next step S80, the compressor 11 is turned on (ON) and the capacity control of the compressor 11 is performed. Specifically, the capacity control of the compressor 11 is performed so that the blown air temperature Te (detected temperature of the post-evaporation temperature sensor 35) of the evaporator 9 becomes the target post-evaporation temperature TEO.

  In the present embodiment, since a fixed displacement compressor that always operates with a constant discharge capacity is used as the compressor 11, specifically, the operation of the compressor 11 is intermittently controlled as shown in FIG. That is, when the post-evaporation temperature Te, which is the actual blown air temperature of the evaporator 9, rises to the target post-evaporation temperature TEO, the electromagnetic clutch 11 a is energized to bring the compressor 11 into operation, and the actual post-evaporation temperature Te of the evaporator 9. When the temperature drops to the target post-evaporation temperature TEO-α, the energization of the electromagnetic clutch 11a is cut off and the compressor 11 is stopped (OFF). Here, α is a hysteresis width for preventing hunting, and is about 1 ° C., for example.

  Thus, by controlling the operation of the compressor 11 intermittently, the operating rate of the compressor 11 and thus the refrigerant discharge capacity are controlled, and the actual post-evaporation temperature Te of the evaporator 9 is maintained near the target post-evaporation temperature TEO. Is done.

  By the way, in the middle season of spring and autumn, the heat load of the air conditioning in the passenger compartment is originally small, so even if the air volume of the blower 8 is reduced to the minimum air volume (Lo), the passenger set the passenger compartment temperature (inside temperature) Tr. It can be maintained near the set temperature Tset. Under such an air conditioning heat load condition, the target blowout temperature TAO is changed from the third predetermined temperature T3 (= 18 ° C.) to the fourth predetermined temperature T4 (= 34 ° C.), which is a predetermined intermediate temperature range in the vicinity of the set temperature Tset. Within range.

  In this case, since the determination in step S60 of FIG. 3 is YES, the process proceeds to step S90, the energization to the drive motor 8b of the blower 8 is cut off, and the blower 8 is completely stopped (OFF). Subsequently, in step S100, energization of the electromagnetic clutch 11a is maintained in a cut-off state, and the compressor 11 is maintained in a complete stop (OFF) state. In each process in steps S70 to S100, a flag that can identify whether the blower 8 and the compressor 11 are in the ON state or the OFF state is set.

  As a result, the interior of the vehicle interior can be made a quiet atmosphere with no fan noise, the comfort of the vehicle interior can be improved, and the power consumption of the fan 8 can be reduced and the driving power of the compressor 11 can be reduced. Moreover, since the automatic stop control of the blower 8 and the compressor 11 is performed by determining a situation where the heat load of the air conditioning in the vehicle interior is small, no manual operation of the occupant is required and no operation burden is imposed on the occupant.

  Further, a third predetermined range that is a predetermined temperature range that falls within a temperature range (for example, 8 ° C. to 4 ° C.) between the second predetermined temperature T2 and the fifth predetermined temperature T5 that sets the air volume of the blower 8 to the minimum air volume (Lo). A range between the temperature T3 and the fourth predetermined temperature T4 (for example, 18 ° C. to 34 ° C.) is set as a range in which the heat load of the air conditioning in the vehicle interior is minimized, and the blower 8 and the compressor 11 are in this minimum air conditioning heat load range. Is automatically stopped, the stopped state of the blower 8 and the compressor 11 is maintained, and when the target blowing temperature TAO fluctuates outside the above-mentioned minimum air conditioning heat load range (for example, 18 ° C to 34 ° C), The blower 8 is always restarted with the minimum air volume.

  Therefore, it is possible to reliably avoid giving the occupant the uncomfortable feeling that the blower 8 is suddenly restarted with an air volume higher than the minimum air volume. This can also contribute to improving passenger comfort.

  Next, the inside / outside air switching control in the embodiment of the present invention will be described with reference to FIG. FIG. 6 is a flowchart of an inside / outside air switching control routine executed by the microcomputer of the air conditioning control device 30. This inside / outside air switching control routine is executed in parallel with the air conditioning control routine.

  First, in step S200, it is determined whether or not the blower 8 is in a stopped state. This is performed based on the flag state when the blower 8 is stopped (OFF) in step S90 or when the blower 8 is set to be activated (ON) in step S70. The determination of the stop state of the blower 8 is performed by determining whether the target blowing temperature TAO calculated in step S20 is a value between the third predetermined temperature T3 (= 18 ° C.) and the fourth predetermined temperature T4 (= 34 ° C.). It may be performed depending on whether or not T3 ≦ TAO ≦ T4).

  As described above, in the present embodiment, the compressor 11 is also stopped in the subsequent step S100. Therefore, the stop state of the blower 8 determined in step S200 is substantially the same as the compressor 11 being stopped. It has become. If the determination result in step S200 is no, the process returns to the start. If the determination result is yes, the process proceeds to step S210.

  In step S210, based on the temperature Tam or Tr and humidity ψ of the air flowing into the evaporator 9 and the post-evaporation temperature Te as the read sensor information, it is estimated by calculation whether the evaporator 9 is in a wet state. To detect.

  Specifically, in step S210, if the state of the inside / outside air switching door 6 at that time is the outside air mode, the outside air temperature Tam from the outside air temperature sensor 31 and the outside air detected by the humidity sensor 33 in the outside air mode are relative to each other. The dew point temperature Tdp of the outside air is calculated from the humidity ψam. The dew point temperature is stored in advance in the computer as well-known wet air diagram data as a map, and is calculated from the detected ambient temperature Tam and relative humidity ψam based on the wet air diagram.

  Alternatively, if it is the inside air mode at the time of execution of step S210, the inside air is calculated from the inside air temperature Tr from the inside air temperature sensor 32 and the relative humidity ψr of the inside air detected by the humidity sensor 33 in the inside air mode based on the wet air diagram. The dew point temperature Tdp is calculated.

  In step S220, the dew point temperature Tdp of the outside air (or the inside air) is compared with the post-evaporation temperature Te detected by the post-evaporation temperature sensor 35, and the dew point temperature is higher than the post-evaporation temperature (Tdp> Te). In addition, it is determined that the evaporator 9 is wet, and when Tdp ≦ Te, it is determined that the evaporator 9 is not wet. If it is determined that the evaporator 9 is not wet, the process returns to the start.

  If it is determined that the evaporator 9 is wet, it is next determined in step S230 based on whether or not the vehicle is traveling and whether or not the vehicle speed V detected by the vehicle speed sensor 37 is zero. If it is determined that the vehicle speed V ≠ 0, that is, the vehicle is traveling, the inside / outside air switching door 6 is set to the inside air mode in step S240. That is, if it is currently the inside air mode, the inside air mode is maintained, and if it is currently the outside air mode, the inside / outside air switching door 6 is controlled to switch from the outside air mode to the inside air mode.

  If it is determined that the vehicle speed V = 0, that is, the vehicle is stopped, the inside / outside air switching door 6 is set to the outside air mode in step S250. That is, if it is the outside air mode, the outside air mode is maintained, and if it is the inside air mode, the inside / outside air switching door 6 is controlled to switch from the inside air mode to the outside air mode.

  As described above, in the present embodiment, the blower 8 is under the condition that the heat load of the air conditioning in the vehicle interior is small, that is, the condition where the target blowing temperature TAO is maintained near the set temperature Tset (18 ° C. ≦ TAO ≦ 34 ° C.). It will be in a stop (OFF) state below. In this state, when an air flow is generated around the wet evaporator 9, the moisture of the evaporator 9 is taken away by the air flow, and the air flow contains moisture. When the air is blown out to the passenger compartment from ˜21, an unpleasant wind hits the occupant.

  Therefore, in this embodiment, when it is determined that the evaporator 9 is wet (condensation) when the blower 8 is controlled to be stopped under a condition where the air conditioning heat load is small, Since the inside / outside air switching door 6 is set to the inside air mode, no air flow is generated around the evaporator 9, and therefore, moist air deprived of moisture from the wet evaporator 9 flows from the ventilation duct 2 into the vehicle interior. There is no. Therefore, it is possible to prevent an unpleasant wind including the moisture of the wet evaporator 9 and further an unpleasant smell from hitting the occupant, thereby improving the comfort of the occupant.

  Further, in the present embodiment, when the evaporator 9 is wet when the blower 8 is stopped, the inside / outside air switching door 6 is set to the inside air mode particularly during vehicle travel. The inflow of air into the ventilation duct 2 can be prevented, and therefore unpleasant winds including the moisture of the wet evaporator 9 and further including unpleasant odors are blown out from the air outlet into the passenger compartment and hit the passenger. Can be prevented and passenger comfort can be improved. Further, when the vehicle is not running, the outside air flows into the ventilation duct 2 and the possibility that unpleasant winds are blown into the passenger compartment is low, so the outside air mode can be set.

  The correspondence between the specific means in the first embodiment and the components of the present invention will be described as follows. The outside air temperature sensor 31, the inside air temperature sensor 32, and the humidity sensor 33 in FIG. Temperature / humidity detection means for detecting the temperature and humidity.

  3 constitutes “determination means for determining that the air-conditioning heat load is in the minimum range equal to or less than a predetermined amount”. 3 constitutes “a blower stopping means for automatically stopping the blower 8 that blows air toward the passenger compartment when it is determined that the air conditioning thermal load is in the minimum range”.

  3 constitutes “compressor stopping means for automatically stopping the compressor 11 when it is determined that the air-conditioning heat load is in the minimum range”.

  3 constitutes “a temperature control means for automatically controlling the air mix door (temperature adjusting means) 17 so that the temperature of the air blown into the passenger compartment becomes the target blowing temperature (TAO)”.

  And step S70 of FIG. 3 constitutes “a blower control means for automatically controlling the air volume blown out into the passenger compartment in accordance with the target blowing temperature (TAO) when the air conditioning heat load is outside the minimum range”.

  Furthermore, step S210 (and S220) in FIG. 6 constitutes “evaporation wetness detection means for detecting the wet state of the evaporator”. Further, the “running state determination means for determining whether or not the vehicle is in a traveling state” is configured by step S230 of FIG. Further, “switching control means for setting the inside / outside air switching door to the inside air mode when the wet state of the evaporator is detected” is configured by step S240 in FIG.

(Second Embodiment)
In the said 1st Embodiment, in the state which the air blower 8 stopped completely, switching control to the inside air mode based on the wetness determination of the evaporator 9 is performed, but in 2nd Embodiment, the air volume of the air blower 8 is the minimum air volume ( Even in the state Lo), switching control to the inside air mode based on the wetness determination of the evaporator 9 is performed.

  FIG. 7 shows the inside / outside air switching control routine of the second embodiment. The same processing steps as those of the inside / outside air switching control routine of the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  In step S202, it is determined whether or not the target blowing temperature TAO is a value (T2 ≦ TAO ≦ T5) between the second predetermined temperature T2 (= 8 ° C.) and the fifth predetermined temperature T5 (= 44 ° C.). That is, in the blower control characteristic diagram shown in FIG. 4, the target blowing temperature TAO is in the range between the second predetermined temperature T2 and the third predetermined temperature T3, and in the range between the fourth predetermined temperature T4 and the fifth predetermined temperature T5. The air volume of the blower 8 is set to the minimum air volume Lo.

  Then, as in the first embodiment, the process after step S210 is a case where it is determined that the evaporator 9 is wet, and the vehicle is switched to or maintained in the inside air mode while the vehicle is traveling.

  When the airflow of the blower 8 is operating at the minimum airflow, the airflow hitting the occupant is extremely small, and the occupant may not feel the presence of the wind. Therefore, in such a state of the minimum air volume Lo, as in the state where the blower 8 is completely stopped, when the evaporator 9 is wet, the wet air from the wet evaporator 9 is included due to the introduction of the outside air during traveling. However, an unpleasant wind containing an unpleasant odor may be blown into the passenger compartment and hit the passenger.

  Therefore, in the second embodiment, as described above, the blower operating state in which the inside / outside air switching control is performed so as not to apply unpleasant wind to the occupant, as described above, the complete stop state of the blower 8 and the minimum air volume Lo state. In the state where there is a possibility that unpleasant wind may hit the occupant, when the wetting of the evaporator 9 is detected, the inside / outside air switching door 6 is set to the inside air mode if the vehicle is traveling. Thus, it is possible to reliably prevent unpleasant wind from being blown into the passenger compartment and hitting the occupant, thereby improving the comfort of the occupant.

(Third embodiment)
In the said 1st Embodiment, in the state which the air blower 8 stopped completely, although switching control to the inside air mode based on the wetness determination of the evaporator 9 is performed, in the state which the evaporator 9 became wet in 3rd Embodiment, Furthermore, switching control to the inside air mode is performed when the post-evaporation temperature Te is equal to or higher than a predetermined temperature.

  FIG. 8 shows an inside / outside air switching control routine of the third embodiment. The same processing steps as those of the inside / outside air switching control routine of the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  In the third embodiment, when it is determined in step S220 that the evaporator 9 is wet, it is determined in step S225 whether the post-evaporation temperature Te is equal to or higher than a predetermined temperature (15 ° C.). When this determination result is YES, that is, when the blower 8 is stopped, the evaporator 9 is wet, and the post-evaporation temperature Te is equal to or higher than a predetermined temperature (for example, 15 ° C.), as in the first embodiment. The process proceeds to step S230 to perform processing for setting the inside / outside air switching door 6 to the inside air mode if the vehicle is traveling and setting the inside / outside air switching door 6 to the outside air mode if the vehicle is not traveling.

  When the determination result in step S225 is NO, the process proceeds to step S250, and the inside / outside air switching door 6 is set to the outside air mode regardless of the traveling state of the vehicle.

  If the evaporator 9 is wet when the post-evaporation temperature Te is relatively high (for example, 15 ° C. or higher), the air that has passed through the evaporator 9 is more unpleasant for the passenger, that is, hot humid air, It becomes a wind containing an unpleasant odor more felt by the high temperature dampness. Therefore, in the third embodiment, it is possible to reliably prevent an unpleasant wind from being applied to the occupant in such a case.

  Even when the evaporator 9 is wet, when the post-evaporation temperature Te is lower than a predetermined temperature (15 ° C.) or when the vehicle is not running, the possibility of unpleasant wind hitting the occupant is low. Mode.

(Other embodiments)
The present invention is not limited to the above embodiments, and can be variously modified as exemplified below.

  (1) In each of the above embodiments, the air conditioning control device 30 automatically stops (OFF) the blower 8 or operates it with a predetermined air volume in accordance with the target blowing temperature TAO. That is, when the blower 8 is automatically stopped, the inside / outside air switching door 6 is controlled to the inside air mode so that unpleasant wind does not hit the occupant. However, the present invention is not limited to this. That is, for example, even when the occupant manually stops the blower 8 by operating the OFF knob 46a, the air conditioning control device 30 can detect the stop state of the blower 8 by a flag or the like. Therefore, as in the above embodiments, the wetness of the evaporator 9 is detected based on the comparison between the dew point temperature of the air and the post-evaporation temperature, and when the vehicle is running, the inside / outside air switching door 6 is controlled to the inside air mode. Further, it is possible to prevent a damp and unpleasant wind from being blown into the passenger compartment and hitting the occupant, thereby improving the comfort of the occupant.

  (2) In each of the above embodiments, by installing the humidity sensor 33 at the suction port of the blower fan 8a, the humidity sensor 33 detects the humidity of the inside air in the inside air mode and the humidity of the outside air in the outside air mode. Although shown, not only this but the humidity sensor is arrange | positioned in the predetermined location in a vehicle interior, for example, the face blower outlet 19 vicinity of an instrument panel, The inside air humidity and the evaporator 9 are dry by this humidity sensor Thus, the humidity of the outside air introduced into the vehicle compartment in the outside air mode may be detected.

  (3) For the outside air humidity, instead of using the humidity sensor 33 installed at the suction port of the blower fan 8a, a humidity sensor is provided outside the vehicle interior, for example, upstream in the vicinity of the external air introduction port 4, and the humidity sensor outside the vehicle interior May be detected directly.

  (4) The outside air humidity is not detected by a humidity sensor mounted in or out of the vehicle, but is air-conditioned by humidity information included in weather information obtained by communication from outside the vehicle, which can be obtained from the communication information terminal mounted on the vehicle. You may make it input into the control apparatus 30. FIG.

  (5) In each of the above-described embodiments, when the wetness of the evaporator 9 is detected in step S210, the humidity sensor (inside air humidity sensor, outside air humidity sensor) 33 disposed at the suction port of the blower fan 8a is used. The dew point temperature of the air passing through the evaporator 9 is calculated using the temperature and humidity of the inside air, or the dew point temperature Tdp of the air passing through the evaporator 9 is calculated using the temperature and humidity of the outside air in the outside air mode. Although an example of detecting the wetting of the evaporator 9 by comparing the magnitude of Tdp with the detected post-evaporating temperature Te has been shown, the present invention is not limited to this, and the wetting state of the evaporator 9 is detected by the following method that does not use the dew point temperature. (Estimation) may be performed.

  (5-1) After-evaporation temperature sensor when the outside air temperature Tam detected by the outside air temperature sensor 31 is a temperature within an intermediate temperature range (for example, 10 to 20 ° C.) that is relatively comfortable for the passenger. If the post-evaporation temperature Te detected by 35 is a temperature at which the evaporator 9 is not frozen (for example, 3 ° C. or more), it is estimated that the evaporator 9 is wet without calculating the dew point temperature of the air.

  (5-2) When the blower 8 is automatically stopped or manually stopped, the evaporator 9 is wet until a predetermined time (for example, 3 minutes) elapses after the blower 8 is stopped. It is considered.

  (5-3) A humidity sensor 38 is further provided in the vicinity of the evaporator 9, and the humidity around the evaporator detected by the humidity sensor 38 is detected in the ventilation duct 2 detected by the humidity sensor 33 disposed at the suction port of the blower fan 8 a. It is estimated that the evaporator 9 is wet when the humidity of the introduced air is higher.

  Based on the estimation results as described above, when the blower 8 is stopped, if the vehicle is running, the air is not blown out from the outlet by controlling the inside / outside air switching door 6 to be in the inside air mode. An unpleasant wind is prevented from hitting the passenger.

  (6) In each of the above embodiments, the minimum heat load range of the vehicle interior air conditioning for determining the stop and operating state of the blower 8 is determined based on the target blowing temperature TAO, but instead of the target blowing temperature TAO, the following Thus, it is possible to determine the minimum heat load range for air conditioning based on various factors.

  (6-1) Using the vehicle interior temperature (inside air temperature) Tr and the solar radiation amount Ts instead of the target outlet temperature TAO, the minimum heat load range for air conditioning is determined. In this case, a temperature range (specifically, a range of 18 ° C. to 25 ° C.) that the occupant feels comfortable is set as the vehicle interior temperature Tr when there is no solar radiation in the vehicle interior. As the amount of solar radiation increases, it shifts to the low temperature side to compensate for the effects of solar radiation. Then, when the vehicle interior temperature Tr is within the comfort temperature range A set in this way, it is determined that the air load is in the minimum heat load range, and automatic stop control of the blower 8 and the compressor 11 is performed. Even if such a determination method is employed, the same operational effects as those of the above embodiments can be exhibited.

When the vehicle interior temperature Tr is outside the comfortable temperature range A corrected by the solar radiation amount, and when the solar radiation amount is equal to or higher than the upper limit value (for example, 700 W / m ² ) of the comfortable temperature range A, the blower 8 and the compressor 11 is activated, and the control of S70 and S80 in FIG. 3 is performed.

  As a modified example, the minimum heat load range of the air conditioning may be determined only by the vehicle interior temperature Tr without considering the solar radiation amount Ts. For example, when the vehicle interior temperature Tr is within the passenger's comfort temperature range (for example, a range of 15 ° C. to 25 ° C.), it may be determined that the heat load minimum range of the air conditioning.

  (6-2) Using the outside air temperature Tam and the amount of solar radiation Ts instead of the target outlet temperature TAO, the minimum heat load range for air conditioning is determined. In this case, a temperature range (specifically, a range of 13 ° C. to 20 ° C.) that the occupant feels comfortable is set as the outside temperature Tam when there is no solar radiation in the passenger compartment, and this comfortable temperature range B is set as the solar radiation. As the amount increases, it shifts to the low temperature side to compensate for the effects of solar radiation. Then, when the outside air temperature Tam is within the comfortable temperature range B set in this way, it is determined that it is the minimum heat load range of the air conditioning, and automatic stop control of the blower 8 and the compressor 11 is performed. Even if such a determination method is employed, the same operational effects as those of the above embodiments can be exhibited.

When the vehicle interior temperature Tr is outside the comfortable temperature range B corrected by the solar radiation amount and when the solar radiation amount is equal to or higher than the upper limit value (for example, 700 W / m ² ) of the comfortable temperature range B, the blower 8 and the compressor 11 is activated, and the control of S70 and S80 in FIG. 3 is performed.

  As a modified example, the minimum heat load range of the air conditioning may be determined only by the outside air temperature Tam without considering the solar radiation amount Ts. For example, when the outside air temperature Tam is within the passenger's comfortable temperature range (for example, a range of 10 ° C. to 20 ° C.), it may be determined as the minimum heat load range of the air conditioning.

  (6-3) Instead of the target outlet temperature TAO, the minimum temperature range of the air conditioning is determined using the temperature difference between the passenger compartment temperature Tr and the set temperature Tset. That is, focusing on the fact that the thermal load of the air conditioning decreases as the temperature difference between the vehicle interior temperature Tr and the set temperature Tset decreases, the temperature difference between the vehicle interior temperature Tr and the set temperature Tset is a predetermined value. It can be determined that the temperature is within the minimum range (for example, within ± 3 ° C.) that is the minimum heat load range for air conditioning.

  (6-4) Instead of the target blowing temperature TAO, the minimum temperature range of the air conditioning is determined using the temperature difference between the outside air temperature Tam and the set temperature Tset. That is, paying attention to the relationship that the thermal load of the air conditioning decreases as the temperature difference between the outside temperature Tam and the set temperature Tset decreases, the temperature difference between the outside temperature Tam and the set temperature Tset is within a predetermined value ( For example, when it is within ± 5 ° C., it can be determined that it is the heat load minimum range of air conditioning.

1 is an overall system configuration diagram showing a first embodiment of the present invention. It is a front view of the air-conditioning panel in a 1st embodiment. It is a flowchart which shows the outline | summary of the air-conditioning control of 1st Embodiment. It is a characteristic view of the air blower control by 1st Embodiment. It is a characteristic figure of the intermittent control of the fixed capacity type compressor by a 1st embodiment. It is a flowchart which shows the outline | summary of the inside / outside air switching control of 1st Embodiment. It is a flowchart which shows the outline | summary of the inside / outside air switching control of 2nd Embodiment. It is a flowchart which shows the outline | summary of the inside / outside air switching control of 3rd Embodiment.

Explanation of symbols

2 ... Ventilation duct (case), 6 ... Inside / outside air switching door, 8 ... Blower
9 ... Evaporator (evaporator as a heat exchanger for cooling), 11 ... Compressor,
30 ... Air conditioning control device, 31 ... Outside air temperature sensor, 32 ... Inside air temperature sensor,
33 ... Humidity sensor, 35 ... Post-evaporation temperature sensor, 37 ... Vehicle speed sensor.

Claims (14)

A ventilation duct (2) for sending air to the passenger compartment;
An inside / outside air switching door (6) for switching between an outside air mode for introducing air outside the vehicle into the ventilation duct and an inside air mode for introducing air inside the vehicle compartment into the ventilation duct;
A blower (8) for generating an air flow toward the passenger compartment in the ventilation duct;
In the vehicle air conditioner, which is disposed in the ventilation duct and includes an evaporator (9) for cooling the air flow.
Evaporation wetness detection means (S210) for detecting the wet state of the evaporator,
A vehicle air conditioner comprising switching control means (S240) for setting the inside / outside air switching door to an inside air mode when a wet state of the evaporator is detected. The vehicle further includes traveling state determining means (S230) for determining whether or not the vehicle is in a traveling state,
2. The vehicle air conditioner according to claim 1, wherein the switching control unit sets the inside / outside air switching door to the inside air mode when the traveling state unit determines that the vehicle is in a traveling state. . 3. The vehicle air conditioner according to claim 1, wherein when the blower is in a stopped state, the switching control unit sets the inside / outside air switching door to the inside air mode. 4. A determination means (S60) for determining that an air conditioning heat load for maintaining the temperature in the passenger compartment at a set temperature is in a minimum range of a predetermined amount or less;
A blower stopping means (S90) for automatically stopping the blower when it is determined that the air conditioning heat load is in the minimum range;
The vehicle air conditioner according to claim 1 or 2, wherein the switching control unit sets the inside / outside air switching door to the inside air mode in accordance with a magnitude of the air conditioning heat load. A refrigeration cycle compressor (11) for creating a cooling state of the evaporator;
The vehicle air conditioner according to claim 4, further comprising compressor stop means (S100) for automatically stopping the compressor when it is determined that the air conditioning heat load is in the minimum range. Temperature adjusting means (17) for adjusting the temperature of the air blown into the vehicle interior;
Temperature control means (S40, S50) for automatically controlling the temperature adjusting means so that the temperature of the air blown into the passenger compartment becomes a target blowing temperature (TAO);
The blower control means (S70) for automatically controlling the air volume of the blower according to the target blowing temperature when the air-conditioning heat load is outside the minimum range. Vehicle air conditioner. The vehicle air conditioner according to claim 6, wherein the switching control means sets the inside / outside air switching door to the inside air mode when the air conditioning heat load falls within the minimum range. The blower control means sets the blower air volume as a minimum air volume in a predetermined range where the air conditioning heat load is outside the minimum range,
The vehicular air conditioning according to claim 6, wherein the switching control means sets the inside / outside air switching door to the inside air mode when the air conditioning heat load becomes a size of the minimum range and the predetermined range. apparatus. The vehicle air conditioner according to any one of claims 4 to 8, wherein the determination unit determines that the air conditioning heat load is in the minimum range based on the target outlet temperature. The said determination means determines that the said air-conditioning heat load exists in the said minimum range based on at least 1 of the said set temperature, the said vehicle interior temperature, external temperature, and the amount of solar radiation. The vehicle air conditioner according to any one of the above. Temperature / humidity detection means (31, 32, 33) for detecting the temperature and humidity of the air introduced into the ventilation duct, and a post-evaporation temperature sensor (35) for detecting the air temperature immediately after passing through the evaporator,
The evaporative wetness detection means calculates the dew point temperature of the air according to the detected temperature and humidity of the air, and when the dew point temperature is higher than the temperature detected by the post-evaporation temperature sensor. The vehicle air conditioner according to any one of claims 1 to 10, wherein the evaporator is determined to be in a wet state. An outside air temperature sensor (31) for detecting the temperature of the outside air, and a post-evaporation temperature sensor (35) for detecting the air temperature immediately after passing through the evaporator,
11. The evaporator wetness detection means determines that the evaporator is in a wet state based on the detected outside air temperature and the temperature detected by the post-evaporation temperature sensor. The vehicle air conditioner described in 1. The vehicle air conditioner according to any one of claims 1 to 10, wherein the evaporative wetness detecting means determines that the evaporator is in a wet state within a predetermined time from the stop of the blower. An humidity sensor (38) for detecting the humidity in the vicinity of the evaporator and a humidity sensor (33) for detecting the humidity of the air introduced into the ventilation duct;
2. The evaporator wetness detection means determines that the evaporator is in a wet state by comparing the detected humidity in the vicinity of the evaporator with the humidity of air introduced into the ventilation duct. The vehicle air conditioner according to any one of 10.

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