JP2009227193A - Air conditioner for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To restrain the temporary generation of the frost in an evaporator. <P>SOLUTION: An inside/outside air switching door 15 for selectively opening and closing an inside air introducing port 12 and an outside air introducing port 13 formed on an air conditioning case 11 is moved between an inside air close position for closing the inside air introducing port 12 and an outside air close position for closing the outside air introducing port 13 by an inside/outside air switching control means. In movement of the inside/outside air switching door 15 from the outside air close position to the inside air close position, when a cabin inner temperature detected by a cabin inner temperature detecting means 41c is higher than an outside air temperature detected by an outside air temperature detecting means 41b by a first prescribed temperature or more, the inside/outside air switching control means performs gradual change control for making the movement time of the inside/outside air switching door 15 from the outside air close position to the inside air close position longer than the case when the cabin inner temperature is not higher than the outside air temperature by the first prescribed temperature or more. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a vehicle air conditioner.

  2. Description of the Related Art Conventionally, in an air conditioner having a variable capacity compressor capable of changing the refrigerant discharge capacity, the blowing temperature of the evaporator (evaporator) cooled by the supply of the refrigerant becomes a low temperature that causes frost (freezing). In some cases, the refrigerant flow rate is suppressed to prevent frost (for example, see Patent Document 1).

  By the way, the capacity change of the compressor is usually detected by a temperature sensor that calculates the target outlet temperature Teo of the evaporator and detects the outlet temperature of the evaporator so that the actual outlet temperature of the evaporator becomes the target outlet temperature Teo. This is realized by feedback control according to the deviation En (= Te−Teo) from the temperature Te.

At this time, in a low temperature region where the occurrence of frost is a concern, the target temperature Teo is increased when the sensing temperature Te of the temperature sensor that detects the outlet temperature of the evaporator is lower than the frost prevention temperature (for example, 2 ° C.). Performs control to set.
JP 2005-178560 A

  However, even when a load decrease occurs such that the outlet temperature of the evaporator suddenly decreases, feedback control is continued, so that the outlet temperature of the evaporator reaches the frost prevention temperature due to the follow-up delay of the feedback control, Temporary frost will occur. There is a problem that a frozen odor is generated along with the temporary frosting of the evaporator, and the frozen odor deteriorates the air-conditioning feeling of passengers in the passenger compartment.

  An object of this invention is to suppress generation | occurrence | production of the temporary frost of an evaporator in view of the said point.

  The present inventors diligently studied a factor that causes a load decrease such that the temperature of the evaporator (18) rapidly decreases within a temperature deviation. After the study, when the air conditioner is in operation in the cold season such as winter, the occupant or the like changes the setting to switch the inside / outside air switching door (15) from the inside air introduction mode to the outside air introduction mode. It has been found that outside air flows into the evaporator (18) and the cooling load of the evaporator (18) is temporarily reduced.

  Therefore, in the invention described in claim 1, the inside / outside air switching door (15) for selectively opening and closing the inside air introduction port (12) and the outside air introduction port (13) formed in the air conditioning case (11), and the inside / outside air Inside / outside air switching control means for moving the switching door (15) between an inside air closing position for closing the inside air introduction port (12) and an outside air closing position for closing the outside air introduction port (13), and an air conditioning case (11) An evaporator (18) arranged to cool the air introduced from at least one of the inside air inlet (12) and the outside air inlet (13), and an evaporator for detecting the temperature of the air that has passed through the evaporator (18) A temperature detection means (41a), an outside air temperature detection means (41b) for detecting the outside air temperature outside the vehicle interior, and a vehicle interior temperature detection means (41c) for detecting the vehicle interior temperature. Inside / outside air switching door (15) outside air When moving from the chain position to the inside air closed position, the vehicle interior temperature detected by the vehicle interior temperature detecting means (41c) is equal to or higher than the first predetermined temperature with respect to the outside air temperature detected by the outside air temperature detecting means (41b). When the temperature is high, the vehicle interior temperature is gradually changed to increase the time required to move the inside / outside air switching door (15) from the outside air closed position to the inside air closed position as compared with the case where the vehicle interior temperature is not higher than the first predetermined temperature. It is characterized by performing control.

  Thus, when the vehicle interior temperature is higher than the outside air temperature by the first predetermined temperature or more, the movement time from the outside air closing position of the inside / outside air switching door (15) by the inside / outside air switching control means to the inside air closing position is lengthened. Thus, a rapid decrease in the temperature of the air flowing into the evaporator (18) can be suppressed.

  Thereby, since the reduction | decrease of the cooling load by the rapid fall of the air temperature which flows in into an evaporator (18) can be suppressed, generation | occurrence | production of temporary frost of an evaporator (18) can be suppressed.

  Further, as in the invention described in claim 2, in the invention described in claim 1, the inside / outside air switching control means moves the inside / outside air switching door (15) from the outside air closed position to the inside air closed position during the gradual change control. You may move to stepwise.

  Further, as in the invention described in claim 3, in the invention described in claim 1, the inside / outside air switching control means moves the inside / outside air switching door (15) from the outside air closing position to the inside air closing time during the gradual change control. It may be moved continuously to the position.

  According to a fourth aspect of the invention, in the invention according to any one of the first to third aspects, the inside / outside air switching control means is the evaporator blown air detected by the evaporator temperature detecting means (41a). When the temperature of the inside / outside air switching door (15) is less than or equal to the second predetermined temperature and the temperature of the evaporator blown air is not less than or equal to the second predetermined temperature, It is characterized by lengthening.

  When the temperature of the evaporator blowing air that has passed through the evaporator (18) is low, frost is likely to be generated in the evaporator (18). By making the movement time to the longer, temporary frost generation of the evaporator (18) can be suppressed.

  Further, as in the invention described in claim 5, in the invention described in any one of claims 1 to 4, a compressor (19) that compresses the refrigerant and circulates it in the evaporator (18); In the case of including discharge capacity control means (19b) for controlling the discharge capacity of the compressor (19) so that the air temperature detected by the evaporator temperature detection means (41a) becomes the target evaporator temperature, the discharge capacity Temporary frost generation in the evaporator (18) due to the follow-up delay of the discharge capacity control of the compressor (19) of the control means (19b) can be suppressed.

  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)
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows an outline of the overall configuration of the first embodiment, and the vehicle air conditioner includes an indoor air conditioning unit 10. The air conditioning unit 10 is disposed inside an instrument panel (not shown) at the foremost part of the vehicle interior, and air-conditions the vehicle interior.

  The air conditioning unit 10 has an air conditioning case 11, and an air passage through which air is blown toward the vehicle interior is formed in the air conditioning case 11. An inside / outside air switching box 14 having an inside air introduction port 12 and an outside air introduction port 13 is disposed at the most upstream portion of the air passage of the air conditioning case 11. An inside / outside air switching door 15 is rotatably disposed in the inside / outside air switching box 14.

  The inside / outside air switching door 15 is driven by a servo motor 16, and is an inside air introduction mode for introducing inside air (vehicle compartment air) from the inside air introduction port 12 and an outside air for introducing outside air (vehicle compartment outside air) from the outside air introduction port 13. Switching to introduction mode. Here, in the inside air introduction mode, the inside / outside air switching door 15 is moved to the outside air closing position where the outside air introduction port 13 is closed, and in the outside air introduction mode, the inside / outside air switching door 15 is moved to the inside air closing position where the inside air introduction port 12 is closed. Moved.

  On the downstream side of the inside / outside air switching box 14, an electric blower 17 that generates an air flow toward the passenger compartment is disposed. The blower 17 is configured such that a centrifugal blower fan 17a is driven by a motor 17b. An evaporator 18 that cools the air flowing in the air conditioning case 11 is disposed on the downstream side of the blower 17. The evaporator 18 is a cooling heat exchanger that cools the air blown from the blower 17 and is one of the elements constituting the refrigeration cycle apparatus 100.

  Note that the refrigeration cycle apparatus 100 is a well-known configuration in which refrigerant is circulated from the discharge side of the compressor 19 to the evaporator 18 via the condenser 20, the liquid receiver 21 and the expansion valve 22 that serves as a decompression unit. Is. In this embodiment, HFC-134a is used as the refrigerant.

  The compressor 19 is rotationally driven by the rotational power of a vehicle engine (not shown) being transmitted through an electromagnetic clutch 19a, a pulley, a belt, and the like. In this example, an external variable capacity compressor that continuously varies the discharge capacity by a control signal from the outside is used as the compressor.

  This external variable capacity compressor is a known one. For example, a discharge capacity control means having an electromagnetic pressure control device for controlling the pressure of the swash plate chamber using the discharge pressure and the suction pressure in the swash plate compressor is provided. A variable capacity device 19b is provided. By controlling the pressure of the swash plate chamber with this capacity changing device 19b, the inclination angle of the swash plate is varied to continuously change the stroke of the piston, that is, the compressor discharge capacity in the range of approximately 0% to 100%. Can do.

  The electromagnetic pressure control device of the capacity variable device 19b changes the control pressure (swash plate chamber pressure) using the discharge pressure and suction pressure of the compressor 19, and the electromagnetic force is adjusted by the control current In. An electromagnetic mechanism and a valve body that is displaced by the balance between the electromagnetic force of the electromagnetic mechanism and the suction pressure, and the pressure loss of the passage that guides the discharge pressure of the compressor 19 into the swash plate chamber is adjusted by this valve body. The pressure is changed.

  Next, the refrigerant is compressed to high temperature and high pressure by the compressor 19, and the high temperature and high pressure refrigerant discharged from the compressor 19 is introduced into a condenser (heat radiator) 20. In this condenser 20, the gas refrigerant dissipates heat to the outside air blown by the cooling electric fan 20a and condenses. The refrigerant that has passed through the condenser 20 is separated into a gas-phase refrigerant and a liquid-phase refrigerant by a liquid receiver 21, and the liquid-phase refrigerant is stored in the liquid receiver 21.

  The high-pressure liquid refrigerant from the liquid receiver 21 is decompressed to a low-pressure gas-liquid two-phase state by the temperature type expansion valve 22, and the decompressed low-pressure refrigerant absorbs heat from the conditioned air and evaporates in the evaporator 18. It has become. The gas refrigerant evaporated in the evaporator 18 is again sucked into the compressor 19 and compressed. As is well known, the temperature type expansion valve 22 automatically adjusts the valve opening so that the degree of refrigerant superheat at the evaporator outlet is maintained at a predetermined value.

  On the other hand, in the air conditioning unit 10, a heater core 23 for heating the air flowing in the air conditioning case 11 is disposed on the downstream side of the evaporator 18. The heater core 23 is a heating heat exchanger that heats the air (cold air) that has passed through the evaporator 18 using warm water (engine cooling water) of the vehicle engine as a heat source, and bypasses the heater core 23 to the side of the air. Is formed.

  An air mix door 25 is rotatably disposed between the evaporator 18 and the heater core 23. The air mix door 25 is driven by a servo motor 26, and its rotational position (opening degree) can be continuously adjusted. The amount of air passing through the heater core 23 (warm air amount) and the amount of air passing through the bypass passage 24 and bypassing the heater core 23 (cold air amount) are adjusted by the opening degree of the air mix door 25, thereby blowing out into the vehicle interior. The temperature of the air is adjusted.

  At the most downstream part of the air passage of the air conditioning case 11, a defroster outlet 27 for blowing the conditioned air toward the front window glass WS of the vehicle, and a face outlet 28 for blowing the conditioned air toward the occupant's face. In addition, three types of air outlets, a foot air outlet 29 for blowing air-conditioned air toward the feet of the passenger, are provided.

  A defroster door 30, a face door 31, and a foot door 32 are rotatably disposed upstream of the air outlets 27 to 29. These doors 30 to 32 are opened and closed by a common servo motor 33 through a link mechanism (not shown).

  Next, the outline of the electric control unit of this embodiment will be described with reference to FIG. 2. A control unit (ECU) 40 constitutes the control means of the present invention, and is a known microcomputer including a CPU, a ROM, a RAM, and the like. And its peripheral circuits.

  The control device 40 stores a control program for air conditioning control in the ROM, and performs various calculations and processes based on the control program. A sensor detection signal from the sensor group 41 and an operation signal from the air conditioning panel 42 are input to the input side of the control device 40.

  The sensor group 41 includes an evaporator temperature sensor 41a that is disposed in the air blowing portion of the evaporator 18 and detects the evaporator blowing air temperature Te, and an outside air temperature sensor that is disposed outside the vehicle and detects the outside air temperature Tam outside the vehicle compartment. 41b, a vehicle interior temperature sensor 41c that is disposed in the vehicle interior and detects the vehicle interior temperature Tr is provided. In addition, various types of sensors that detect the intake air humidity RH, the solar radiation amount Ts, the hot water temperature Tw, and the like are provided. Sensors 41d to 41f are provided.

  Here, the evaporator temperature sensor 41a corresponds to the evaporator temperature detecting means, the outside air temperature sensor 41b corresponds to the outside air temperature detecting means, and the vehicle interior temperature sensor 41c corresponds to the vehicle interior temperature detecting means.

  The air conditioning panel 42 is disposed in the vicinity of an instrument panel (not shown) in front of the driver's seat in the passenger compartment, and includes the following operation switches 42a to 42e that are operated by a passenger. The temperature setting switch 42a outputs a signal of the set temperature in the passenger compartment, and the inside / outside air switching switch 42b outputs a signal for manually setting the inside air mode and the outside air mode by the inside / outside air switching door 15.

  The blowout mode switch 42c outputs a signal for manually setting a face mode, a bi-level mode, a foot mode, a foot defroster mode, and a defroster mode known as blowout modes. The air volume changeover switch 42d outputs a signal for manually setting on / off of the blower 17 and airflow change of the blower 17.

  The air conditioner switch 42e switches between the operating state and the stopped state of the compressor 19. When the air conditioner switch 42e is turned off, the control current In is forcibly set to 0, and the discharge capacity of the compressor 19 is set to substantially 0 capacity. The compressor 19 is substantially stopped. When the air conditioner switch 42e is turned on, a predetermined control current In calculated by the control device 40 is output, and the compressor 19 is activated.

  Connected to the output side of the control device 40 are an electromagnetic clutch 19a of the compressor 19, a variable capacity device 19b, servo motors 16, 26, 33 that form electric drive means for each device, a motor 17b of the blower 17, an electric fan 20a, and the like. The operation of these devices is controlled by the output signal of the control device 40.

  Next, the operation of this embodiment in the above configuration will be described. First, the outline of the operation as the vehicle air conditioner will be described. By turning on the air volume switching switch 42d of the air conditioning panel 42 and operating the blower 17, air is blown into the ventilation path in the air conditioning unit 10.

  When the air conditioner switch 42e which is a compressor operation switch of the air conditioning panel 42 is turned on, the electromagnetic clutch 19a is energized by the control device 40, the electromagnetic clutch 19a is connected, and the compressor 19 is rotationally driven by the vehicle engine.

  Further, the control device 40 determines the control current In of the capacity varying device 19b of the compressor 19 according to the flowchart of FIG. 3 described later, and the compressor 19 operates in a state of a predetermined discharge capacity. Thereby, since the refrigerant circulates in the evaporator 18 in the refrigeration cycle 100, the blown air can be cooled and dehumidified by the evaporator 18, and the conditioned air can be blown into the passenger compartment.

  Next, the overall capacity control executed by the control device 40 will be described with reference to FIG. 3. First, in step S100, the control device 40 reads a detection signal from the sensor group 41, an operation signal from the operation panel 42, and the like. Next, the target blowing temperature Tao of the blowing air into the vehicle interior is calculated in step S110. This target blowing temperature Tao is the temperature of the air blown into the vehicle interior required to maintain the vehicle interior at the set temperature Tset set by the occupant by the temperature setting switch 42a of the operation panel 42 regardless of the air conditioning thermal load fluctuation. The target blowing temperature Tao is calculated based on the set temperature Tset, the outside air temperature Tam, the inside air temperature Tr, and the solar radiation amount Ts as is well known.

  Next, in step S120, the target evaporator temperature Teo of the evaporator 18 is calculated based on the above-described target blowing temperature Tao. This target evaporator temperature Teo is the target temperature of the evaporator blown air Te. Thereafter, in step S130, a control current In for compressor capacity control is calculated.

  This control current In determines the target low pressure of the electromagnetic pressure control device in the capacity variable device 19b of the compressor 19, and the control current In is the actual evaporator blowout detected by the evaporator temperature sensor 41a. The air temperature Te is determined to be the target evaporator temperature Teo.

  In step S140, the control current In is output to the variable capacity device 19b, and the capacity control of the compressor 19 is executed.

  By the way, the control current In is supplied from the evaporator temperature sensor 41a that detects the outlet temperature of the evaporator 18 so that the actual evaporator outlet air temperature Te detected by the evaporator temperature sensor 41a becomes the target evaporator temperature Teo. It is determined by feedback control according to the deviation En (= Te−Teo) between the sensed temperature Te and the target evaporator temperature Teo.

  For this reason, when the load on the evaporator 18 is suddenly reduced, frost is temporarily generated in the evaporator 18 due to a delay in following the feedback control. In addition, when the setting change which changes the inside / outside air switching door 15 from inside air introduction mode to outside air introduction mode is made, the load of the evaporator 18 decreases rapidly.

  Therefore, in the present embodiment, gradual change control is performed to suppress the temporary frost generation of the evaporator 18 at the time of mode switching for switching the inside / outside air switching door 15 from the inside air introduction mode to the outside air introduction mode.

  Next, the gradual change control of the inside / outside air switching door 15 of this embodiment will be described based on the control flowchart of FIG. Here, FIG. 4 is a flowchart showing a flow of gradual change control of the inside / outside air switching door 15.

  The gradual change control of the inside / outside air switching door 15 starts when the inside / outside air switching switch 42b is set to the outside air introduction mode by the occupant. First, in step S200, the outside air temperature Tam detected by the outside air temperature sensor 41b and the vehicle interior temperature Tr detected by the vehicle interior temperature sensor 41c are read.

  In step S210, the outside air temperature Tam is subtracted from the vehicle interior temperature Tr to calculate the inside / outside temperature difference ΔT between the vehicle interior temperature Tr and the outside air temperature Tam (ΔT = Tr−Tam).

  In step S230, it is determined whether the internal / external temperature difference ΔT is equal to or higher than a first predetermined temperature. Here, if the inside / outside temperature difference ΔT is large, when the servo motor 16 moves the inside / outside air switching door 15 from the outside air closed position to the inside air closed position, the temperature of the air blown from the evaporator 18 rapidly decreases. Frost is likely to occur in the evaporator 18. The first predetermined temperature is set in advance to a temperature at which temporary frost is expected to be generated in the evaporator 18 through experiments or the like, and is set to 10 ° C., for example.

  Therefore, if it is determined in step S230 that the internal / external temperature difference ΔT is equal to or higher than the first predetermined temperature, in step S240, the temporary movement time (temporary slowdown) of the internal / external air switching door 15 from the external air closed position to the internal air closed position is determined. Variable time).

  The temporary gradual change time f (ΔT) is calculated based on a control map in which the gradual change time is set according to the internal / external temperature difference ΔT. For example, when the internal / external temperature difference ΔT is 10 ° C., the temporary gradual change time is set to 10 seconds, and when the internal / external temperature difference ΔT is 30 ° C., the temporary gradual change time is set to 15 seconds. To do.

  Next, in step S240, the true gradual change time RFtime is calculated from the gradual change constant K determined in accordance with the cooling capacity for cooling the blown air of the evaporator 18 and the temporary gradual change time f (ΔT) ( RFtime = K × f (ΔT)).

  The gradual change constant K is a constant determined based on the condition that the frost is likely to be generated in the evaporator 18, and when the evaporator blown air temperature Te of the evaporator 18 is equal to or lower than the second predetermined temperature, 2 A larger value is set as compared with a case where the temperature is higher than the predetermined temperature. The gradual change constant K is stored in advance in the air conditioning controller 40. That is, when frost is likely to occur in the evaporator 18, the gradual change time RFtime is lengthened.

  In step S250, the inside / outside air switching door 15 is moved from the outside air closed position to the inside air closed position over the gradual change time RFtime. The movement of the inside / outside air switching door 15 is performed based on a control map stored in advance in a ROM or the like of the control device 40. In this embodiment, the inside / outside air switching door 15 is continuously moved from the outside air closed position to the inside air closed position. Moved.

  On the other hand, if it is determined in step S230 that the internal / external temperature difference ΔT is not equal to or higher than the first predetermined temperature, the internal / external air switching door 15 is set without setting the gradual change time because it is difficult for the evaporator 18 to generate frost. The normal control for moving from the outside air closed position to the inside air closed position is performed.

  As described above, when the passenger compartment temperature is higher than the outside air temperature by the first predetermined temperature or more, the control device 40 evaporates by increasing the movement time from the outside air closing position of the inside / outside air switching door 15 to the inside air closing position. A sudden drop in the air flowing into the vessel 18 can be suppressed.

  Thereby, since the reduction | decrease in the cooling load by the rapid fall of the air which flows in into the evaporator 18 can be suppressed, generation | occurrence | production of the temporary frost of the evaporator 18 can be suppressed.

  Further, when the temperature of the evaporator blown air that has passed through the evaporator 18 is low, frost is likely to be generated in the evaporator 18, and therefore the movement time of the inside / outside air switching door 15 from the outside air closed position to the inside air closed position is long. By making the length longer, generation of temporary frost in the evaporator 18 can be suppressed.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIG. Parts that are the same as or equivalent to those in the first embodiment are given the same reference numerals, and descriptions thereof are omitted. Here, FIG. 5 is a flowchart showing a main part of the gradual change control of the inside / outside air switching door 15 in the present embodiment.

  In the first embodiment, in step S250, the inside / outside air switching door 15 is continuously moved from the outside air closing position to the inside air closing position over the gradual change time RTtime. However, in this embodiment, the inside / outside air switching door 15 is moved. Then, a gradual change time RTtime is waited at an intermediate position between the outside air closing position and the inside air closing position, and the stage is moved stepwise from the outside air closing position to the inside air closing position.

  Specifically, as shown in FIG. 5, in step S250, based on the control map stored in advance in the ROM or the like of the control device 40, the outside air closed position is moved to the intermediate position, and the gradual change time RTtime is reached at the intermediate position. Wait and move from the intermediate position to the inside air closed position.

  As described above, the same effect as that of the first embodiment can be obtained by the gradual change control of the inside / outside air switching door 15 that moves the inside / outside air switching door 15 stepwise from the outside air closing position to the inside air closing position.

(Other embodiments)
The present invention is not limited to the above-described embodiment, and can be variously modified as follows.

  (1) In the above-described embodiment, the evaporator temperature sensor 41a detects the temperature of the blown air from the evaporator 18, but is not limited to this. For example, the surface temperature of the evaporator 18 is directly measured. It may be detected.

  (2) In the above-described embodiment, the gradual change constant K is determined based on the evaporator blown air temperature Te. However, the present invention is not limited to this, and the condition that the frost of the evaporator 18 is likely to occur. It may be determined according to. For example, you may determine according to the characteristics of cycle structure apparatus, such as the magnitude | size of the cooling capacity of the evaporator 18. FIG.

  (3) In the above-described embodiment, the control device 40 starts the gradual change control of the inside / outside air switching door 15 when the inside / outside air switching switch 42b is set to the outside air introduction mode (manual setting) by the occupant. However, the gradual change control of the inside / outside air switching door 15 may be started when switching from the inside air introduction mode to the outside air introduction mode in the automatic air conditioner mode.

  (4) In the second embodiment described above, the control device 40 moves the inside / outside air switching door 15 stepwise from the outside air closing position to the intermediate position to the inside air closing position in the gradual change control of the inside / outside air switching door 15. However, the present invention is not limited to this, and the movement may be performed in stages by dividing it into a plurality of stages.

It is a schematic block diagram of the vehicle air conditioner in 1st Embodiment. It is a schematic block diagram of the electric control part in 1st Embodiment. It is a schematic flowchart of the capacity | capacitance control of the compressor in 1st Embodiment. It is a flowchart which shows the flow of the gradual change control of the inside / outside air switching door in 1st Embodiment. It is a flowchart which shows the principal part of the gradual change control of the inside / outside air switching door in 2nd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Air-conditioning case 12 Inside air introduction port 13 Outside air introduction port 15 Inside / outside air switching door 17 Blower 18 Evaporator 19 Compressor 41a Evaporator temperature detection means 41b Outside air temperature detection means 41c Car interior temperature detection means

Claims (5)

An inside / outside air switching door (15) that selectively opens and closes the inside air introduction port (12) and the outside air introduction port (13) formed in the air conditioning case (11);
An inside / outside air switching control means for moving the inside / outside air switching door (15) between an inside air closing position for closing the inside air introduction port (12) and an outside air closing position for closing the outside air introduction port (13);
An evaporator (18) which is disposed in the air conditioning case (11) and cools air introduced from at least one of the inside air inlet (12) and the outside air inlet (13);
Evaporator temperature detecting means (41a) for detecting the temperature of the evaporator blown air that has passed through the evaporator (18);
An outside air temperature detecting means (41b) for detecting outside air temperature outside the passenger compartment;
Vehicle interior temperature detecting means (41c) for detecting the vehicle interior temperature,
In the case where the inside / outside air switching control means moves the inside / outside air switching door (15) from the outside air closed position to the inside air closed position, the vehicle interior temperature detected by the vehicle interior temperature detecting means (41c) When the outside air temperature detected by the outside air temperature detecting means (41b) is higher than the first predetermined temperature by a temperature higher than the first predetermined temperature, the vehicle interior temperature is not higher than the first predetermined temperature by the outside air temperature. In comparison, the vehicular air conditioner is characterized in that gradual change control is performed to increase the movement time of the inside / outside air switching door (15) from the outside air closing position to the inside air closing position.   The vehicle according to claim 1, wherein the inside / outside air switching control means moves the inside / outside air switching door (15) stepwise from the outside air closing position to the inside air closing position in the gradual change control. Air conditioner.   The vehicle according to claim 1, wherein the inside / outside air switching control means continuously moves the inside / outside air switching door (15) from the outside air closing position to the inside air closing position in the gradual change control. Air conditioner. Evaporator temperature detecting means (41a) for detecting the temperature of the air that has passed through the evaporator (18);
The inside / outside air switching control means is configured such that when the temperature of the evaporator outlet air detected by the evaporator temperature detecting means (41a) is equal to or lower than a second predetermined temperature, the temperature of the evaporator outlet air is the second temperature. The movement time from the outside air closed position to the inside air closed position of the inside / outside air switching door (15) is increased as compared with a case where the temperature is not lower than a predetermined temperature. The vehicle air conditioner described. A compressor (19) for compressing the refrigerant and circulating it in the evaporator (18);
Discharge capacity control means (19b) for controlling the discharge capacity of the compressor (19) so that the air temperature detected by the evaporator temperature detection means (41a) becomes a target evaporator temperature. The vehicle air conditioner according to any one of claims 1 to 4.