JP6024305B2 - Air conditioner for vehicles - Google Patents

Description

  The present invention relates to a vehicle air conditioner including a heat pump cycle.

  Conventionally, Patent Document 1 discloses a vehicle air conditioner that heats air blown into a vehicle interior by a heat pump cycle to heat the vehicle interior. Furthermore, in the heat pump cycle of Patent Document 1, when frost formation occurs in the outdoor heat exchanger that functions as an evaporator that evaporates the refrigerant during heating operation, the high-temperature and high-pressure refrigerant discharged from the compressor is removed from the outdoor heat exchanger. The outdoor heat exchanger is defrosted by switching to a refrigerant circuit in a defrosting mode that flows into the refrigerant.

Japanese Utility Model Publication No. 6-61526

  However, in the vehicle air conditioner disclosed in Patent Document 1, if the heat pump cycle is switched to the refrigerant circuit in the defrost mode in order to defrost the outdoor heat exchanger during the heating operation, the blown air can be heated. Since it will be lost, a passenger | crew's feeling of heating will be worsened while defrosting an outdoor heat exchanger.

  In view of the above points, an object of the present invention is to suppress a passenger's feeling of heating from deteriorating when performing defrosting of an outdoor heat exchanger in a vehicle air conditioner including a heat pump cycle.

The present invention has been devised in order to achieve the above object. In the first aspect of the present invention, the compressor (11) that compresses and discharges the refrigerant, and the blown air that is blown into the refrigerant and the passenger compartment. A heat pump cycle having an indoor condenser (13) for exchanging heat with each other, an outdoor heat exchanger (16) for exchanging heat between the refrigerant and the outside air, and refrigerant circuit switching means (15a, 20) for switching a refrigerant circuit through which the refrigerant circulates. (10), the refrigerant circuit switching means (15a, 20), when heating the passenger compartment, causes the refrigerant discharged from the compressor (11) to flow into the indoor condenser (13) and the outdoor heat. When switching to a heating mode refrigerant circuit that evaporates the refrigerant in the exchanger (16) and defrosting the outdoor heat exchanger (16), the refrigerant discharged from the compressor (11) is used as the outdoor heat exchanger. (16) Defrost mode to flow into Is configured to switch the refrigerant circuit de further provides a viable constructed vehicular air conditioning system pre-air conditioning to start air-conditioning the cabin before an occupant gets into the vehicle,
Frost determination means (S62, S65) for determining that frost formation has occurred in the outdoor heat exchanger (16), refrigerant circuit control means (50c) for controlling the operation of the refrigerant circuit switching means (15a, 20), With
The refrigerant circuit control means (50c) switches to the refrigerant circuit in the defrosting mode when it is determined by the frost determination means (S62, S65) that frost formation has occurred and pre-air conditioning is being executed. To control the operation of the refrigerant circuit switching means (15a, 20),
The frost formation determination means (S62, S65) determines that frost formation has occurred when the outdoor unit temperature (Tout) of the outdoor heat exchanger (16) is lower than a predetermined reference temperature (KT1 to KT3). as well as, at the start of the pre-air conditioning, which determines whether frost is generated on the basis of the value stored at the previous vehicle system stop, as the reference temperature (KT1~KT3), execution of the flop les conditioning The reference temperature (KT2, KT3) used in the vehicle is set to a value lower than the reference temperature (KT1, KT2) used when determining based on the value stored when the vehicle system was stopped last time. Features.

  According to this, the refrigerant circuit control means (50c) determines that frost formation has occurred in the outdoor heat exchanger (16) by the frost formation determination means (S62, S65), and pre-air conditioning is executed. Since the refrigerant circuit is switched to the defrost mode refrigerant circuit, the defrosting of the outdoor heat exchanger (16) is performed during pre-air conditioning before the occupant gets into the vehicle.

  In other words, the refrigerant circuit control means (50c) is not performing pre-air conditioning even if frost formation determination means (S62, S65) determines that frost formation has occurred in the outdoor heat exchanger (16). At this time, switching to the refrigerant circuit in the defrosting mode is prohibited.

Therefore, it is not switched to the refrigerant circuit in the defrosting mode when the occupant is in the vehicle, and deterioration of the occupant's feeling of heating when defrosting the outdoor heat exchanger (16) can be suppressed.
In the invention according to claim 2, the compressor (11) that compresses and discharges the refrigerant, the indoor condenser (13) that exchanges heat between the refrigerant and the blown air blown into the vehicle interior, the refrigerant and the outside air The heat pump cycle (10) having the outdoor heat exchanger (16) for exchanging heat and the refrigerant circuit switching means (15a, 20) for switching the refrigerant circuit through which the refrigerant circulates, and the refrigerant circuit switching means (15a, 20) When heating the passenger compartment, a refrigerant circuit in a heating mode in which the refrigerant discharged from the compressor (11) flows into the indoor condenser (13) and evaporates in the outdoor heat exchanger (16). When the defrosting of the outdoor heat exchanger (16) is performed, the refrigerant discharged from the compressor (11) is switched to the defrosting mode refrigerant circuit that flows into the outdoor heat exchanger (16). Composed Furthermore, an executable-configured vehicular air-conditioning system pre-air conditioning to start air-conditioning the cabin before an occupant gets into the vehicle,
Frost determination means (S62, S65) for determining that frost formation has occurred in the outdoor heat exchanger (16), refrigerant circuit control means (50c) for controlling the operation of the refrigerant circuit switching means (15a, 20), With
The refrigerant circuit control means (50c) switches to the refrigerant circuit in the defrosting mode when it is determined by the frost determination means (S62, S65) that frost formation has occurred and pre-air conditioning is being executed. To control the operation of the refrigerant circuit switching means (15a, 20),
When the outdoor unit temperature (Tout) of the outdoor heat exchanger (16) is lower than a predetermined reference temperature (KT1 to KT3), the frost formation determination means (S62, S65) ), And it is determined that the reference temperature (KT1 to KT3) is set to a lower temperature with the elapsed time from the start of the pre-air conditioning.
According to this, the same effect as that of the first aspect of the invention can be obtained.

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

1 is an overall configuration diagram of a vehicle air conditioner according to an embodiment. It is a block diagram which shows the electric control part of the vehicle air conditioner of one Embodiment. It is a flowchart which shows the control processing of the vehicle air conditioner of one Embodiment. It is a flowchart for determining an operation mode among control processing of an air-conditioner for vehicles of one embodiment. It is a flowchart for determining an air blower voltage among the control processing of the vehicle air conditioner of one Embodiment. It is a flowchart for determining the rotation speed of a compressor among the control processing of the vehicle air conditioner of one Embodiment. It is another flowchart for determining the rotation speed of a compressor among the control processing of the vehicle air conditioner of one Embodiment.

  Hereinafter, an embodiment of the present invention will be described with reference to FIGS. The vehicle air conditioner 1 of the present embodiment is applied to an electric vehicle that obtains a driving force for traveling from a traveling electric motor. In this electric vehicle, electric power supplied from an external power supply (commercial power supply) when the vehicle is stopped is charged in the battery B as the storage means, and electric power stored in the battery B is supplied to the electric motor for traveling when the vehicle travels. Run.

  Furthermore, in the electric vehicle according to the present embodiment, the electric power (electric energy) stored in the battery B is supplied to various electric components of the vehicle air conditioner 1 through the air conditioning control device 50 described later, thereby The air conditioner 1 is operated. In other words, the vehicle air conditioner 1 according to the present embodiment operates when supplied with the electric power stored in the battery B.

  Next, the detailed structure of the vehicle air conditioner 1 is demonstrated using FIG. 1, FIG. The vehicle air conditioner 1 of the present embodiment can perform pre-air conditioning that performs air conditioning of the passenger compartment before the occupant gets into the vehicle, in addition to normal air conditioning that performs air conditioning of the passenger compartment when the vehicle is traveling. Further, in the vehicle air conditioner 1, during the charging of the battery B, pre-air conditioning can be performed not only with the electric power stored in the battery B but also with electric power supplied from an external power source.

  The vehicle air conditioner 1 includes a heat pump cycle (vapor compression refrigeration cycle) 10 as temperature adjusting means for adjusting the temperature of the blown air blown into the vehicle interior, and the blown air adjusted in temperature by the heat pump cycle 10 in the vehicle interior. And an air conditioning control device 50 for controlling the operation of various electric components of the vehicle air conditioning device 1.

  First, the heat pump cycle 10 recirculates the air in the heating mode that heats the air and heats the vehicle interior, the refrigerant circuit in the cooling mode that cools the air and cools the air, and the air that has been cooled and dehumidified. When frosting occurs in the refrigerant circuit in the dehumidifying and heating mode for heating and dehumidifying and heating the vehicle interior, and further in the outdoor heat exchanger 16 functioning as an evaporator for evaporating the refrigerant in the heat pump cycle 10 in the heating mode, The refrigerant circuit in the defrosting mode for defrosting can be switched.

  In FIG. 1, the refrigerant flow in the heating mode is indicated by a white arrow, the refrigerant flow in the cooling mode is indicated by a black arrow, the refrigerant flow in the dehumidifying heating mode is indicated by a hatched arrow, The flow of the refrigerant in the frost mode is indicated by a hatched arrow.

  The heat pump cycle 10 includes a compressor 11 that compresses and discharges refrigerant, an indoor condenser 13 and an indoor evaporator 18 that serve as indoor heat exchangers that heat or cool blown air, and heating that serves as decompression means that decompresses and expands the refrigerant. A fixed throttle 14, a cooling fixed throttle 17, and an on-off valve 15a as a refrigerant circuit switching means and a three-way valve 20 are provided.

  The heat pump cycle 10 employs an HFC refrigerant (specifically, R134a) as a refrigerant, and constitutes a vapor compression subcritical refrigeration cycle in which the high-pressure side refrigerant pressure does not exceed the refrigerant critical pressure. ing. Of course, you may employ | adopt HFO type refrigerant | coolants (for example, R1234yf). Furthermore, refrigeration oil for lubricating the compressor 11 is mixed in the refrigerant, and a part of the refrigeration oil circulates in the cycle together with the refrigerant.

  The compressor 11 is disposed inside a vehicle hood outside the passenger compartment, and sucks refrigerant in the heat pump cycle 10 and compresses and discharges it. A fixed displacement type compression mechanism 11a having a fixed discharge capacity is used as an electric motor 11b. It is comprised as an electric compressor which drives. Specifically, various types of compression mechanisms such as a scroll type compression mechanism and a vane type compression mechanism can be adopted as the fixed capacity type compression mechanism 11a.

  The electric motor 11b is an AC motor whose operation (number of rotations) is controlled by the AC voltage output from the inverter 61. Further, the inverter 61 outputs an AC voltage having a frequency corresponding to the control signal output from the air conditioning control device 50. And the refrigerant | coolant discharge capability of the compressor 11 is changed by this frequency (rotation speed) control. Therefore, the electric motor 11b constitutes a discharge capacity changing unit of the compressor 11.

  The refrigerant inlet side of the indoor condenser 13 is connected to the discharge port side of the compressor 11. The indoor condenser 13 is disposed in a casing 31 that forms an air passage for the blown air blown into the vehicle interior in the indoor air conditioning unit 30 and blows air by exchanging heat between the refrigerant circulating in the interior and the blown air. It is a heat exchanger for heating which heats air.

  The refrigerant outlet side of the indoor condenser 13 is connected to the refrigerant inlet side of the outdoor heat exchanger 16 through a heating fixed throttle 14 that depressurizes the refrigerant in the heating mode. As the heating fixed throttle 14, an orifice, a capillary tube or the like can be adopted. Of course, as long as the function of depressurizing the refrigerant in the heating mode can be exhibited, a variable throttle mechanism such as an electric expansion valve with a fully open function may be adopted without being limited to the fixed throttle.

  Further, in the present embodiment, a bypass passage 15 is provided that guides the refrigerant flowing out of the indoor condenser 13 to the refrigerant inlet side of the outdoor heat exchanger 16 by bypassing the heating fixed throttle 14. An opening / closing valve 15 a for opening and closing the bypass passage 15 is disposed in the bypass passage 15.

  The on-off valve 15a constitutes refrigerant circuit switching means for switching a refrigerant circuit in the cooling mode, a refrigerant circuit in the heating mode, a refrigerant circuit in the dehumidifying heating mode, and a refrigerant circuit in the defrosting mode, and is output from the air conditioning control device 50. This is a solenoid valve whose operation is controlled by a control signal. Specifically, the on-off valve 15a of the present embodiment opens during the cooling mode and the defrost mode, and closes during the heating mode and the dehumidifying heating mode.

  Note that the pressure loss that occurs when the refrigerant passes through the bypass passage 15 with the on-off valve 15a open is in contrast to the pressure loss that occurs when the refrigerant passes through the heating fixed throttle 14 with the on-off valve 15a closed. And very small. Accordingly, when the on-off valve 15 a is open, almost the entire flow rate of the refrigerant flowing out of the outdoor heat exchanger 16 flows to the refrigerant inlet side of the outdoor heat exchanger 16 through the bypass passage 15.

  The outdoor heat exchanger 16 is disposed in the vehicle bonnet, and exchanges heat between the refrigerant on the downstream side of the indoor condenser 13 that circulates inside and the air outside the vehicle (outside air) blown from the blower fan 16a. The blower fan 16 a is an electric blower in which the rotation speed (blowing capacity) is controlled by a control voltage output from the air conditioning control device 50.

  A three-way valve 20 is connected to the refrigerant outlet side of the outdoor heat exchanger 16. The three-way valve 20 constitutes a refrigerant circuit switching means for switching the refrigerant circuit in each operation mode described above together with the on-off valve 15a, and an electric type whose operation is controlled by a control signal output from the air conditioning control device 50. This is a three-way valve.

  Specifically, the three-way valve 20 of the present embodiment switches to a refrigerant circuit that connects the refrigerant outlet side of the outdoor heat exchanger 16 and the cooling fixed throttle 17 during the cooling mode and the dehumidifying heating mode, In the defrosting mode, the refrigerant circuit is switched to a refrigerant circuit that connects the refrigerant outlet side of the outdoor heat exchanger 16 and the refrigerant inlet side of the accumulator 19 disposed on the suction port side of the compressor 11.

  The basic configuration of the cooling fixed throttle 17 is the same as that of the heating fixed throttle 14. The refrigerant inlet side of the indoor evaporator 18 is connected to the outlet side of the cooling fixed throttle 17. The indoor evaporator 18 is arranged in the casing 31 of the indoor air-conditioning unit 30 on the upstream side of the blower air flow of the indoor condenser 13, and exchanges heat between the refrigerant circulating in the interior and the blown air so that the blown air is exchanged. A cooling heat exchanger for cooling.

  The inlet side of the accumulator 19 is connected to the refrigerant outlet side of the indoor evaporator 18. The accumulator 19 is a gas-liquid separator that separates the gas-liquid of the refrigerant that has flowed into the accumulator and stores excess refrigerant in the cycle. Further, the suction port side of the compressor 11 is connected to the gas phase refrigerant outlet of the accumulator 19.

  Next, the indoor air conditioning unit 30 will be described. The indoor air-conditioning unit 30 is disposed inside the instrument panel (instrument panel) at the foremost part of the vehicle interior, and the blower 32, the above-described indoor evaporator 18, the indoor condenser 13, air, and the like are formed in a casing 31 that forms the outer shell. The mix door 34 and the like are accommodated.

  The casing 31 is formed of a resin (for example, polypropylene) having a certain degree of elasticity and excellent in strength, and forms an air passage for blown air to be blown into the vehicle interior. An inside / outside air switching device 33 as an inside / outside air switching means for switching and introducing the inside air (vehicle compartment air) and the outside air (vehicle compartment outside air) into the casing 31 is arranged on the most upstream side of the blast air flow of the casing 31. Yes.

  The inside / outside air switching device 33 adjusts the opening area of the inside air introduction port through which the inside air is introduced into the casing 31 and the outside air introduction port through which the outside air is introduced, by the inside / outside air switching door, and the air volume between the inside air volume and the outside air volume. The ratio is continuously changed. The inside / outside air switching door is driven by an electric actuator 62 for the inside / outside air switching door, and the operation of the electric actuator 62 is controlled by a control signal output from the air conditioning controller 50.

  On the downstream side of the air flow of the inside / outside air switching device 33, a blower 32 that blows air sucked through the inside / outside air switching device 33 toward the vehicle interior is arranged. The blower 32 is an electric blower that drives a centrifugal multiblade fan (sirocco fan) with an electric motor, and the number of rotations (air flow rate) is controlled by a control voltage output from the air conditioning control device 50.

  On the downstream side of the air flow of the blower 32, the indoor evaporator 18 and the indoor condenser 13 are arranged in the order of the indoor evaporator 18 → the indoor condenser 13 with respect to the flow of the blown air. In other words, the indoor evaporator 18 is arranged on the upstream side of the air flow with respect to the indoor condenser 13.

  In the casing 31, an air mix door 34 that adjusts the air volume ratio between the air volume that passes through the indoor condenser 13 and the air volume that does not pass through the indoor condenser 13 among the blown air after passing through the indoor evaporator 18 is disposed. Has been. The air mix door 34 is driven by an electric actuator 63 for driving the air mix door, and the operation of the electric actuator 63 is controlled by a control signal output from the air conditioning control device 50.

  Further, in the most downstream part of the air flow of the casing 31, blown air that has passed through the indoor condenser 13 or blown air that has passed through the cold air bypass passage that bypasses the indoor condenser 13 is blown out to the vehicle interior that is the air-conditioning target space. Opening holes are provided. Specifically, the opening hole includes a defroster opening hole 37a that blows conditioned air toward the inner surface of the vehicle front window glass, a face opening hole 37b that blows conditioned air toward the upper body of the passenger in the passenger compartment, and the feet of the passenger The foot opening hole 37c which blows air-conditioning wind toward is provided.

  The air flow downstream sides of the defroster opening hole 37a, the face opening hole 37b, and the foot opening hole 37c are respectively connected to a face air outlet, a foot air outlet, and a defroster air outlet provided in the vehicle interior via ducts that form air passages. It is connected to an outlet (both not shown).

  During the cooling mode and the dehumidifying heating mode, the hot air reheated by the indoor condenser 13 among the blown air cooled by the indoor evaporator 18 by adjusting the opening degree of the air mix door 34. And the air volume ratio of the cool air that bypasses the indoor condenser is adjusted. And the temperature of the mixed air which mixed warm air and cold air, ie, the blowing air which blows off into a vehicle interior, is adjusted by adjustment of this air volume ratio.

  In the cooling mode, the air mix door 34 may be displaced to a position where the total air volume of the blown air after passing through the indoor evaporator 18 bypasses the indoor condenser 13.

  Further, on the upstream side of the air flow of the defroster opening hole 37a, the face opening hole 37b, and the foot opening hole 37c, the opening areas of the defroster door 38a and the face opening hole 37b for adjusting the opening area of the defroster opening hole 37a are adjusted. A foot door 38c for adjusting the opening area of the face door 38b and the foot opening hole 37c is disposed.

  The defroster door 38a, the face door 38b, and the foot door 38c constitute the outlet mode switching means for switching the outlet mode, and are connected to the electric actuator 64 for driving the outlet mode door via a link mechanism or the like. It is connected and rotated in conjunction with it. The operation of the electric actuator 64 is also controlled by a control signal output from the air conditioning control device 50.

  In addition, as the air outlet mode switched by the air outlet mode switching means, the face air outlet is fully opened and air is blown out from the face air outlet toward the passenger's upper body, both the face air outlet and the foot air outlet. A bi-level mode that blows air toward the upper body and feet of passengers in the passenger compartment, a foot that fully opens the foot outlet and opens the defroster outlet by a small opening, and mainly blows air from the foot outlet. There is a mode and a foot defroster mode in which the foot outlet and the defroster outlet are opened to the same extent and air is blown out from both the foot outlet and the defroster outlet.

  Furthermore, it can also be set as the defroster mode which fully opens a defroster blower outlet and blows air from a defroster blower outlet to the vehicle front window glass inner surface by a passenger's manual operation of the blowout mode changeover switch provided in the operation panel.

  Next, the electric control unit of this embodiment will be described. The air conditioning control device 50 shown in FIG. 2 includes a known microcomputer including a CPU, a ROM, a RAM, and the like and its peripheral circuits. Then, various computations and processes are performed based on the air conditioning control program stored in the ROM, and the on-off valve 15a and the three-way valve 20 constituting the inverter for the compressor 11 and the refrigerant circuit switching means connected to the output side thereof. The operation of various air conditioning components such as the blower fan 16a, the blower 32, and the various electric actuators 62 to 65 described above is controlled.

  Further, on the input side of the air-conditioning control device 50, an inside air sensor 51 as an inside air temperature detecting means for detecting a vehicle interior temperature (inside air temperature) Tr, and an outside air temperature detecting means for detecting a vehicle outside temperature (outside air temperature) Tam. An outside air sensor 52, a solar radiation sensor 53 as a solar radiation amount detecting means for detecting the solar radiation amount Ts irradiated into the passenger compartment, a discharge temperature sensor 54 for detecting the refrigerant discharge temperature Td of the compressor 11 discharge refrigerant, and the refrigerant discharge refrigerant 11 The discharge pressure sensor 55 for detecting the discharge refrigerant pressure Pd, the evaporator temperature sensor 56 for detecting the refrigerant evaporation temperature (evaporator temperature) Te in the indoor evaporator 18, and the outdoor heat for detecting the outdoor temperature Tout of the outdoor heat exchanger 16. A detection signal of a sensor group for air conditioning control such as the exchanger temperature sensor 57 is input.

  In the cooling mode, the discharge refrigerant pressure Pd of the present embodiment is the high-pressure side refrigerant pressure of the cycle from the refrigerant discharge port side of the compressor 11 to the cooling fixed throttle 17 inlet side, and in the heating mode, the compressor 11 This is the high-pressure side refrigerant pressure of the cycle from the refrigerant discharge port side to the heating fixed throttle 17 inlet side.

  Moreover, the evaporator temperature sensor 56 of this embodiment specifically detects the heat exchange fin temperature of the indoor evaporator 18. Of course, as the evaporator temperature sensor 56, temperature detection means for detecting the temperature of other portions of the indoor evaporator 18 may be employed, or temperature detection for directly detecting the temperature of the refrigerant itself flowing through the indoor evaporator 18. Means may be employed. The same applies to the outdoor heat exchanger temperature sensor 57.

  Further, on the input side of the air conditioning control device 50, operation signals from various air conditioning operation switches provided on an operation panel disposed in the vicinity of the instrument panel in the front part of the vehicle interior are input. Specifically, various air conditioning operation switches provided on the operation panel include an operation switch of the vehicle air conditioner 1, an auto switch for setting or canceling the automatic control of the vehicle air conditioner 1, and an operation mode switching for switching the operation mode. Switch, blow-out mode switching switch for switching the blow-out port mode, air volume setting switch of the blower 32, vehicle interior temperature setting switch as target temperature setting means for setting the vehicle interior target temperature Tset, reduction of energy consumed for air conditioning There is an economy switch or the like which is a means for requesting energy saving.

  In addition, the air conditioning control device 50 according to the present embodiment transmits and receives control signals to and from a wireless terminal 70 (specifically, a remote controller) or mobile communication means (specifically, a mobile phone and a smartphone) carried by a passenger. A transmission / reception unit 50a is provided.

  The operation panel 60 and the wireless terminal 70 are requested to execute pre-air conditioning operations such as a pre-air conditioning start switch for starting the pre-air conditioning operation and a timer setting switch for starting the pre-air conditioning operation at a predetermined time. Air conditioning request means are provided.

  The air-conditioning control device 50 is configured integrally with control means for controlling various air-conditioning components connected to the output side of the air-conditioning control device 50, but is configured to control the operation of each air-conditioning component (hardware). Software and software) constitutes a control means for controlling the operation of each component for air conditioning.

  For example, in the present embodiment, in the air conditioning control device 50, the configuration (hardware and software) that controls the operation of the on-off valve 15a and the three-way valve 20 constituting the refrigerant circuit switching unit constitutes the refrigerant circuit control unit 50c, The structure which controls the action | operation of the air blower 32 which blows ventilation air toward a vehicle interior comprises the air blower control means 50b.

  Next, the operation of this embodiment in the above configuration will be described using the flowcharts of FIGS. This control process is executed if power is supplied from the battery to the air conditioning control device 50 even when the vehicle is stopped. Each of the control steps in FIG. 3 to FIG. 7 constitutes various function realizing means that the air conditioning control device 50 has.

  First, in step S1, whether or not the vehicle air conditioner 1 is to be operated, that is, whether or not the auto switch is turned on (ON) while the operation switch of the operation panel 60 is turned on, or pre-air conditioning is started. It is determined whether or not the switch is turned on. And when it determines with operating the vehicle air conditioner 1, it progresses to step S2. Note that the fact that the pre-air-conditioning start switch is turned on includes the start of the pre-air-conditioning operation by the timer setting described above.

  In step S2, initialization such as initialization of a flag, a timer, and initial position alignment of the stepping motor constituting the electric actuator described above is performed. In this initialization, some of the flags and calculation values that are stored when the previous operation of the vehicle air conditioner 1 is completed or when the vehicle system is stopped may be maintained.

  Next, in step S3, an operation signal of the operation panel 60 is read and the process proceeds to step S4. In step S4, the vehicle environmental state signal used for air conditioning control, that is, the detection signals of the above-described sensor groups 51 to 57 for air conditioning control, etc. are read, and the process proceeds to step S5.

In step S5, a target blowing temperature TAO of the vehicle cabin blowing air is calculated. The target blowing temperature TAO is a value that is determined in order to quickly bring the inside air temperature Tr close to the occupant's desired target temperature Tset, and is calculated by the following formula F1.
TAO = Kset × Tset−Kr × Tr−Kam × Tam−Ks × Ts + C (F1)
Here, Tset is the target temperature in the vehicle interior set by the vehicle interior temperature setting switch, Tr is the vehicle interior temperature (inside air temperature) detected by the inside air sensor 51, and Tam is detected by the outside air sensor 52. The temperature outside the passenger compartment (outside air temperature), and Ts is the amount of solar radiation detected by the solar radiation sensor 53. Kset, Kr, Kam, and Ks are control gains, and C is a correction constant.

  The target outlet temperature TAO can also be expressed as an index indicating the air conditioning heat load required for the vehicle air conditioner 1 in order to keep the passenger compartment at a desired temperature. Further, the target blowout temperature TAO calculated by the above formula F1 is a control target value that can be used in both the cooling mode and the heating mode. In the heating mode, the above formula F1 is used to suppress power consumption. You may correct | amend so that it may be a value a little lower than the target blowing temperature TAO calculated by (1).

  In step S6, the operation mode of the heat pump cycle 10 is determined. Details of the control in step S6 will be described with reference to FIG. In step S6, basically, the occupant determines the operation mode selected by the operation mode switch on the operation panel 60 (hereinafter, the operation mode selected by the occupant is referred to as the normal mode), and the outdoor heat exchanger 16 When it is determined that frost formation has occurred, the defrosting mode is determined.

  First, in step S61 of FIG. 4, based on the outdoor unit temperature Tout detected by the outdoor heat exchanger temperature sensor 57, the frosting level is referred to with reference to a control map stored in advance in the ROM of the air conditioning controller 50. Determine FL. More specifically, in this embodiment, it is determined that the frost level FL is increased as the outdoor unit temperature Tout decreases.

  The frost level FL is a variable (parameter) that increases as the possibility of frost formation in the outdoor heat exchanger 16 increases, and the frost level FL is 1 or more. It shows that there is a high possibility that frost formation has actually occurred.

  Specifically, as shown in the control characteristic diagram described in step S61 of FIG. 4, when the outdoor unit temperature Tout is in the decreasing process, if the outdoor unit temperature Tout ≦ the first reference temperature KT1, the frost level is set. If FL = 3 and the first reference temperature KT1 <outdoor temperature Tout ≦ second reference temperature KT2, the frost level FL = 2 and the second reference temperature KT2 <outdoor temperature Tout ≦ third reference temperature KT2 If the third reference temperature KT3 <the outdoor unit temperature Tout, the frost level FL = 0.

  On the other hand, when the outdoor unit temperature Tout is in the process of rising, if the fourth reference temperature KT4 ≦ the outdoor unit temperature Tout, the frost level FL = 0, and the third reference temperature KT3 ≦ the outdoor unit temperature Tout <fourth reference temperature. If KT4, the frost level FL = 1, and if the second reference temperature KT2 ≦ outdoor temperature Tout <the third reference temperature KT3, the frost level FL = 2, and the outdoor temperature Tout <the second reference temperature KT2. If there is frost level FL = 3.

  Each predetermined temperature has a relationship of KT1 <KT2 <KT3 <KT4. In this embodiment, specifically, KT1 = −20 ° C., KT2 = −17 ° C., KT3 = −14 ° C., KT4 = −. 11 ° C. Moreover, the temperature difference of each predetermined temperature is set as a hysteresis width for preventing control hunting.

  Next, in step S62, it is determined whether or not the value FL_OLD storing the frost level FL at the previous stop of the vehicle system is 1 or more. If it is determined in step S62 that the frost level FL_OLD at the previous vehicle system stop is 1 or more, the process proceeds to step S63. On the other hand, if it is determined that the frost level FL at the previous stop of the vehicle system is less than 1, that is, 0, the process proceeds to step S65.

  In step S63, it is determined whether or not the pre-air conditioning is started. When it is determined in step S63 that the pre-air conditioning is started, the process proceeds to step S64, the operation mode of the heat pump cycle 10 is determined as the defrosting mode, and the process proceeds to step S65. On the other hand, if it is determined that the pre-air conditioning is not started, the process proceeds to step S65.

  The start time of pre-air conditioning in step S63 means a timing (that is, when the vehicle air-conditioning apparatus 1 starts air-conditioning of the vehicle interior when the pre-air-conditioning start switch is turned on (ON)). Accordingly, it is determined in step S63 that the pre-air-conditioning is started, only once until the vehicle air-conditioning apparatus 1 is activated and stopped.

  In step S65, it is determined whether or not the frost level FL is 2 or more. If it is determined in step S65 that the frost level FL is 2 or more, the process proceeds to step S66. On the other hand, if it is determined that the frost level FL is not 2 or higher, the process proceeds to step S68, the operation mode of the heat pump cycle 10 is determined to be the normal mode, and the process proceeds to step S7.

  In step S66, it is determined whether or not the pre-air conditioning operation is being executed. If it is determined in step S66 that the pre-air conditioning operation is being performed, the process proceeds to step S67, the operation mode is determined as the defrosting mode, and the process proceeds to step S7. On the other hand, if it is determined that the pre-air conditioning operation is not being executed, the process proceeds to step S68, and the operation mode is determined to be the normal mode.

  As described above, when the frost level FL or FL_OLD is 1 or more, there is a high possibility that the outdoor heat exchanger 16 is frosted. Therefore, in the control steps S62 and S65 of the present embodiment, when the frost level FL or FL_OLD is 1 or more, it is determined that frost is generated in the outdoor heat exchanger 16. That is, the control steps S62 and S65 of the present embodiment constitute a frost formation determining means described in the claims.

  In subsequent steps S7 to S12, control states of various air conditioning component devices connected to the output side of the air conditioning control device 50 are determined. First, in step S <b> 7, a target air flow rate of air blown by the blower 32, that is, a blower motor voltage to be applied to the electric motor of the blower 32 is determined.

  Details of the control in step S7 will be described with reference to FIG. First, in step S71, it is determined whether or not the auto switch of the operation panel 60 is turned on. If it is determined in step S71 that the auto switch is not turned on, the process proceeds to step S72, and the blower motor voltage that is the passenger's desired air volume set by the air volume setting switch of the operation panel 60 is determined. Proceed to S8.

  Specifically, the air volume setting switch of the present embodiment can set five levels of air volume of Lo → M1 → M2 → M3 → Hi, and the blower motor voltage is set in the order of 4V → 6V → 8V → 10V → 12V. Determined to be higher.

  On the other hand, if it is determined in step S71 that the auto switch is turned on, the process proceeds to step S73, and the target air temperature determined in step S4 is referred to with reference to the control map stored in advance in the air conditioning control device 50. A temporary blower level f (TAO) is determined based on TAO.

  More specifically, as shown in the control characteristic diagram described in step S73 of FIG. 5, the target blowing temperature TAO has an extremely low temperature range (−30 ° C. or lower in this embodiment) and an extremely high temperature range (in this embodiment). The temporary blower level f (TAO) is set near the maximum value at 80 ° C. or higher), and the air volume of the blower 32 is brought close to the maximum value.

  Further, as the target blowing temperature TAO increases from the extremely low temperature range toward the intermediate temperature range (10 ° C. to 40 ° C. in the present embodiment), the temporary blower level f (TAO) is decreased, and further, the target As the blowing temperature TAO decreases from the extremely high temperature range toward the intermediate temperature range, the provisional blower level f (TAO) is decreased to decrease the air volume of the blower 32. Further, when the target blowing temperature TAO enters the intermediate temperature range, the provisional blower level f (TAO) is set near the minimum value, and the air volume of the blower 32 is brought close to the minimum value.

  In the next step S74, it is determined whether or not the pre-air conditioning operation is being executed. If it is determined in step S74 that the pre-air conditioning operation is not being executed, the process proceeds to step S75, and the upper limit value f (outdoor heat exchanger) of the blower level is set to 30 (maximum value), and the process proceeds to step S77. On the other hand, if it is determined that the pre-air conditioning operation is being performed, the process proceeds to step S76, and an upper limit value f (outdoor heat exchanger) corresponding to the outdoor unit temperature Tout is determined.

  Specifically, as shown in the control characteristic diagram described in step S76 of FIG. 5, as the outdoor unit temperature Tout of the outdoor heat exchanger 16 decreases, the blower level upper limit value f (outdoor heat exchanger) Reduce. Further, when the outdoor unit temperature Tout becomes lower than the first reference temperature KT1 (specifically, −20 ° C.) at which the frost level FL described in step S61 of FIG. The upper limit value f (outdoor heat exchanger) is lowered.

  In subsequent step S77, the temporary blower level f (TAO) determined in step S73 is compared with the upper limit value f (outdoor heat exchanger) of the blower level determined in step S75 or S76. The value is determined as the blower level, and the process proceeds to step S78. In step S78, the blower motor voltage actually applied to the electric motor of the blower 32 is determined according to the blower level, and the process proceeds to step S8.

  Next, in step S8 shown in FIG. 3, the control signal output to the suction port mode, that is, the electric actuator 62 for driving the inside / outside air switching door is determined. This suction port mode is also determined with reference to a control map stored in advance in the air conditioning control device 50 based on the target outlet temperature TAO. In the present embodiment, the outside air mode for introducing outside air is basically given priority, but the inside air mode for introducing inside air is selected when the target blowing temperature TAO is in a very low temperature range and high cooling performance is desired. The

  In step S9, a control signal output to the electric actuator 63 for driving the outlet mode, that is, the outlet mode door is determined. This air outlet mode is also determined based on the target air temperature TAO with reference to a control map stored in the air conditioning controller 50 in advance. In the present embodiment, the outlet mode is sequentially switched from the face mode to the bi-level mode to the foot mode as the target outlet temperature TAO increases from the low temperature region to the high temperature region.

  Therefore, in summer, when the target air temperature TAO tends to be in the low temperature range, the face mode is mainly used. In spring and autumn, when the target air temperature TAO is likely to be in the middle temperature region, mainly in the bi-level mode. Foot mode is selected.

  Furthermore, a humidity detecting means for detecting the relative humidity in the vicinity of the vehicle window glass is provided, and the window glass is highly likely to be fogged based on the relative humidity RHW on the surface of the window glass calculated from the detection value of the humidity detecting means. If it is determined, the foot defroster mode or the defroster mode may be selected.

  In step S10, the opening degree of the air mix door 34, that is, the control signal output to the electric actuator 63 for driving the air mix door is determined. In the present embodiment, in the heating mode, the air mix door 34 is displaced so that the total air volume of the blown air after passing through the indoor evaporator 18 flows into the indoor condenser 13.

  In the defrosting mode, the air mix door 34 is displaced so that the total air volume of the blown air after passing through the indoor evaporator 18 bypasses the indoor condenser 13. Further, during the cooling mode and the dehumidifying heating mode, the air mix door 34 is displaced so that the temperature TAV of the blown air blown into the room approaches the target blowing temperature TAO.

  In the present embodiment, a value calculated from the evaporator temperature Te and the discharge refrigerant temperature Td is used as the temperature TAV of the blown air. Of course, a blown air temperature detecting means for detecting the temperature of the blown air blown into the passenger compartment may be provided, and the value detected thereby may be used as the blown air temperature TAV.

  In step S11, the refrigerant discharge capacity of the compressor 11, that is, the rotational speed of the compressor 11 is determined. Here, a basic method for determining the rotational speed of the compressor 11 will be described. For example, in the cooling mode, the refrigerant evaporation temperature (evaporator temperature) in the indoor evaporator 18 is referred to with reference to a control map stored in advance in the air conditioning control device 50 based on the target outlet temperature TAO determined in step S5. Te target blowing temperature TEO is determined.

  Then, a deviation En (TEO−Te) between the target blowing temperature TEO and the blowing air temperature Te is calculated, and a deviation change rate Edot (En− (En− ()) obtained by subtracting the previously calculated deviation En−1 from the currently calculated deviation En. En-1)), and based on the fuzzy inference based on the membership function and rules stored in the air conditioning controller 50 in advance, the rotational speed change amount Δf_C with respect to the previous compressor rotational speed fCn-1 is calculated. Ask.

  Further, in the heating mode and the dehumidifying heating mode, the discharge-side refrigerant pressure (high-pressure side refrigerant pressure) is referred to a control map stored in advance in the air-conditioning control device 50 based on the target blowing temperature TAO determined in step S5. ) Determine the target high pressure PDO for Pd.

  Then, a deviation Pn (PDO−Pd) between the target high pressure PDO and the discharge side refrigerant pressure Pd is calculated, and a deviation change rate Pdot (Pn− (Pn− ( Pn-1)) is used to calculate the rotational speed change amount Δf_H with respect to the previous compressor rotational speed fHn-1 based on the fuzzy inference based on the membership function and rules stored in the air conditioning controller 50 in advance. Ask.

  Details of the control in step S11 will be described with reference to FIGS. First, in step S111, a rotational speed change amount Δf_C in the cooling mode is obtained. Step S111 in FIG. 6 describes a fuzzy rule table used as a rule. In this rule table, Δf_C is determined based on the above-described deviation En and deviation change rate Edot so that frosting of the indoor evaporator 26 is prevented.

  In step S112, the rotational speed change amount Δf_H in the heating mode and the dehumidifying mode is obtained. In FIG.6 S112, the fuzzy rule table | surface used as a rule is described. In this rule table, Δf_H is determined so as to prevent an abnormal increase in the high-pressure side refrigerant pressure Pd based on the above-described deviation Pn and deviation change rate Pdot.

  Next, in step S113, it is determined whether or not the current operation of the vehicle air conditioner 1 is an operation as pre-air conditioning. If it is determined in step S113 that the operation is pre-air conditioning, the process proceeds to step S114. If it is determined in step S113 that the operation is not pre-air conditioning, the process proceeds to step S125 described later. move on.

  In step S114, it is determined whether or not the air conditioning stop flag f (A / C) indicating that the operation of the vehicle air conditioner 1 is prohibited is 1. The air conditioning stop flag f (A / C) is 1 when the operation of the vehicle air conditioner 1 is prohibited.

  When it is determined in step S114 that the air conditioning stop flag f (A / C) is 1, the process proceeds to step S115, and the start switch (IG switch) of the vehicle system is not turned on by a user operation. It is determined whether or not the state (OFF) is changed to the input state (ON). On the other hand, when it is determined in step S114 that the air conditioning stop flag f (A / C) is not 1, the process proceeds to step S117.

  Further, if it is determined in step S115 that the start switch has been changed to ON, the air conditioning stop flag f (A / C) is set to 0 in step S116, and the process proceeds to step S117. On the other hand, if it is not determined in step S115 that the start switch has been changed to ON, the process proceeds to step S117 without changing the air conditioning stop flag f (A / C).

  In step S117, it is determined whether or not the remaining charge amount SOC of the battery B is higher than the reference remaining charge amount KSOC (in this embodiment, KSOC = 24%). If it is determined in step S117 that the remaining power SOC of the battery B is not higher than the reference remaining power KSOC, that is, it is determined that the remaining power SOC of the battery B is less than or equal to the reference remaining power KSOC. In S118, the power supply voltage of the external power supply is determined.

  In step S118, it is determined whether the voltage (execution value) of the external power source is 100V (error range ± 10V) or 200V (error range ± 20V). When it is determined in step S118 that the power supply voltage is 200 V, the process proceeds to step S119, and the upper limit value of power that can be consumed by the various electric components of the vehicle air conditioner 1 for air conditioning is determined. Is set to 1600 W, and the process proceeds to step S124.

  On the other hand, if it is determined in step S118 that the power supply voltage is 100 V or if it is not charged, the process proceeds to step S120, the air conditioning stop flag f (A / C) is set to 1, and the process proceeds to step S121. In step S121, the use permitted power f (POWER) is set to 0 W, and the process proceeds to step S124. That is, in step S121, it is determined to stop the operation of the vehicle air conditioner 1.

  If it is determined in step S117 that the remaining charge SOC of the battery B is higher than the reference remaining charge KSOC, the process proceeds to step S122. In step S122, it is determined whether or not the air conditioning stop flag f (A / C) is zero. When it is determined in step S122 that the air conditioning stop flag f (A / C) is 0, the process proceeds to step S123, and it is determined that the air conditioning stop flag f (A / C) is not 0. In this case, the process proceeds to step S121.

  In step S123, as shown in FIG. 7, the permitted use power f (POWER) is determined, and the process proceeds to step S124. Specifically, in step S123, when the economy switch of the operation panel 60 is not turned on, regardless of whether or not the vehicle is supplied with power from external power, the permitted use power f (POWER) is set to 2500 W. To decide. On the other hand, when the economy switch is turned on and the vehicle is not supplied with power from external power, the permitted power f (POWER) is determined to be 800W.

  In addition, when the economy switch is turned on and the vehicle is supplied with power from external power of 100V (effective value), the allowable power f (POWER) is determined to be 900 W, and the economy switch is turned on. Furthermore, when the vehicle is supplied with power from an external power of 200 V (effective value), the use permission power f (POWER) is determined to be 1700 W.

  In step S124, based on the power consumption difference obtained by subtracting the actual power consumption of various electric components from the use permitted power f (POWER), the compressor is referred to by referring to a control map stored in the air conditioning control device 50 in advance. 11 is determined, and the process proceeds to step S125. Specifically, as shown in step S124 of FIG. 7, the upper limit value Δf_PRE is determined to increase as the power consumption difference increases.

  In step S125, it is determined whether or not the operation mode determined in step S6 is the cooling mode. If it is determined in step S125 that the operation mode determined in step S6 is the cooling mode, the process proceeds to step S126, where Δf_C and Δf_PRE are compared, and the smaller value is changed in the rotation speed of the compressor 11. The amount Δf is determined, and the process proceeds to step S128.

  On the other hand, if it is determined in step S125 that the operation mode determined in step S6 is not the cooling mode, the process proceeds to step S127, where Δf_H and Δf_PRE are compared and the smaller value is changed in the rotational speed of the compressor 11. The amount Δf is determined, and the process proceeds to step S128.

  In step S128, it is determined whether or not the economy switch of operation panel 60 is turned on. In step S128, if the economy switch is not turned on, the process proceeds to step S129, the upper limit value IVOmax of the rotation speed of the compressor 11 is set to 10000 rpm, and if the economy switch is turned on, the process proceeds to step S130 and the compression is performed. The upper limit value IVOmax of the rotation speed of the machine 11 is set to 7000 rpm.

  In the next step S131, the value obtained by adding the rotational speed change amount Δf to the previous compressor rotational speed fn−1 is compared with the upper limit value IVOmax of the rotational speed of the compressor 11, and the smaller value is determined this time. The compressor speed fn is determined, and the process proceeds to step S12. The determination of the compressor speed fn in step S11 is not performed every control cycle τ in which the main routine of FIG. 7 is repeated, but every predetermined control interval (1 second in the present embodiment).

  Next, in step S12 shown in FIG. 3, the operating state of the refrigerant circuit switching means, that is, the operating states of the on-off valve 15a and the three-way valve 20 is determined. Specifically, as described above, the on-off valve 15a of the present embodiment opens during the cooling mode and the defrost mode, and closes during the heating mode and the dehumidifying heating mode.

  The three-way valve 20 switches to a refrigerant circuit connecting the refrigerant outlet side of the outdoor heat exchanger 16 and the cooling fixed throttle 17 in the cooling mode and the dehumidifying heating mode, and exchanges outdoor heat in the heating mode and the defrosting mode. It switches to the refrigerant circuit which connects the refrigerant | coolant exit side of the container 16, and the refrigerant | coolant inlet side of the accumulator 19 arrange | positioned at the inlet side of the compressor 11. FIG.

  In step S13, the air-conditioning control device 50 applies various air-conditioning components 11 (61), 15a, 20, 16a, 32, 62-64 to the control state determined in steps S7 to S12 described above. Control signal and control voltage are output. In continuing step S14, it waits for control period (tau), and if progress of control period (tau) is determined, it will return to step S3.

  Since the vehicle air conditioner 1 according to the present embodiment performs the control process as described above, it operates as follows according to the operation mode.

(A) Heating mode In the heating mode, the refrigerant circuit of the heat pump cycle 10 is connected to the compressor 11, the indoor condenser 13, the heating fixed throttle 14, the outdoor heat exchanger 16 (→ The refrigerant circuit is switched to the refrigerant circuit in which the refrigerant circulates in the order of the three-way valve 20) → the accumulator 19 → the compressor 11. That is, a refrigeration cycle is configured in which the indoor condenser 13 functions as a radiator and the outdoor heat exchanger 16 functions as an evaporator.

  Therefore, in the heat pump cycle 10 in the heating mode, the refrigerant compressed by the compressor 11 radiates heat to the blown air blown from the blower 32 by the indoor condenser 13. Thereby, the blowing air which passes the indoor condenser 13 is heated, and heating of a vehicle interior is implement | achieved. The refrigerant that has flowed out of the indoor condenser 13 is decompressed by the heating fixed throttle 14 and flows into the outdoor heat exchanger 16.

  The refrigerant that has flowed into the outdoor heat exchanger 16 absorbs heat from the vehicle exterior air blown from the blower fan 16a and evaporates. The refrigerant that has flowed out of the outdoor heat exchanger 16 flows into the accumulator 19 through the three-way valve 20. The gas-phase refrigerant separated from the gas and liquid by the accumulator 19 is sucked into the compressor 11 and compressed again.

(B) Cooling mode In the cooling mode, the refrigerant circuit of the heat pump cycle 10 is connected to the compressor 11 → the indoor condenser 13 (→ bypass passage 15) → the outdoor heat exchanger 16 (→ The refrigerant circuit circulates in the order of three-way valve 20) → cooling fixed throttle 17 → indoor evaporator 18 → accumulator 19 → compressor 11 in this order. That is, a refrigeration cycle is configured in which the indoor condenser 13 and the outdoor heat exchanger 16 function as a radiator that radiates heat to the refrigerant, and the indoor evaporator 18 functions as an evaporator that evaporates the refrigerant.

  Therefore, in the heat pump cycle 10 in the cooling mode, the high-pressure and high-temperature refrigerant compressed by the compressor 11 exchanges heat with a part of the blown air after passing through the indoor evaporator 18 in the indoor condenser 13 to Part is heated. Furthermore, the refrigerant that has flowed out of the indoor evaporator 18 flows into the outdoor heat exchanger 16 through the bypass passage 15, and radiates heat by exchanging heat with the outside air blown from the blower fan 16 a in the outdoor heat exchanger 16.

  The refrigerant that has flowed out of the outdoor heat exchanger 16 flows into the cooling fixed throttle 17 via the three-way valve 20 and is decompressed and expanded by the cooling fixed throttle 17. The low-pressure refrigerant decompressed by the cooling fixed throttle 17 flows into the indoor evaporator 18, absorbs heat from the blown air blown from the blower 32, and evaporates. The air blown through the indoor evaporator 18 is cooled by the endothermic action of the refrigerant.

  As described above, a part of the blown air cooled by the indoor evaporator 18 is heated by the indoor condenser 13 so that the blown air blown into the vehicle interior approaches the target blowing temperature TAO. It is adjusted and cooling of the passenger compartment is realized. Further, the refrigerant that has flowed out of the indoor evaporator 18 flows into the accumulator 19. The gas-phase refrigerant separated from the gas and liquid by the accumulator 19 is sucked into the compressor 11 and compressed again.

(C) Dehumidifying Heating Mode In the dehumidifying heating mode, the refrigerant circuit of the heat pump cycle 10 is, as shown by the hatched arrows in FIG. 1, the compressor 11 → the indoor condenser 13 → the heating fixed throttle 14 → the outdoor heat exchanger. The refrigerant circuit circulates in the order of 16 (→ three-way valve 20) → cooling fixed throttle 17 → indoor evaporator 18 → accumulator 19 → compressor 11. That is, a refrigeration cycle is configured in which the indoor condenser 13 and the outdoor heat exchanger 16 function as a radiator that radiates heat to the refrigerant, and the indoor evaporator 18 functions as an evaporator that evaporates the refrigerant.

  Therefore, in the heat pump cycle 10 in the dehumidifying and heating mode, the high-pressure and high-temperature refrigerant compressed by the compressor 11 exchanges heat with a part of the blown air that has passed through the indoor evaporator 18 in the indoor condenser 13 and blown air. A part of is heated. Further, the refrigerant flowing out of the indoor evaporator 18 is decompressed by the heating fixed throttle 14 and flows into the outdoor heat exchanger 16. The refrigerant flowing into the outdoor heat exchanger 16 exchanges heat with the outside air blown from the blower fan 16a to radiate heat.

  The refrigerant that has flowed out of the outdoor heat exchanger 16 flows into the cooling fixed throttle 17 via the three-way valve 20 and is decompressed and expanded by the cooling fixed throttle 17. The low-pressure refrigerant decompressed by the cooling fixed throttle 17 flows into the indoor evaporator 18, absorbs heat from the blown air blown from the blower 32, and evaporates. Due to the endothermic action of the refrigerant, the blown air passing through the indoor evaporator 18 is cooled and dehumidified. The subsequent operation is the same as in the cooling mode.

  As described above, in the dehumidifying and heating mode, as in the cooling mode, the blown air cooled by the indoor evaporator 18 is heated by the indoor condenser 13 and blown out into the vehicle interior to perform dehumidification heating in the vehicle interior. be able to. At this time, since the on-off valve 15a is closed in the dehumidifying and heating mode, the pressure and temperature of the refrigerant flowing into the outdoor heat exchanger 16 can be lowered than in the cooling mode.

  Therefore, the temperature difference between the refrigerant temperature and the outside air temperature in the outdoor heat exchanger 16 can be reduced, and the heat radiation amount of the refrigerant in the outdoor heat exchanger 16 can be reduced. Thereby, in dehumidification heating mode, the thermal radiation amount of the refrigerant | coolant in the indoor condenser 12 can be increased, and the heating capability of the ventilation air in the indoor condenser 12 can be improved rather than the cooling mode.

(D) Defrosting mode In the defrosting mode, it is determined in control steps S62 and S65 constituting the frosting determining means that frosting has occurred in the outdoor heat exchanger 16, and at the start of pre-air conditioning or Performed during pre-air conditioning. In this embodiment, once switched to the defrosting mode, it is not switched to the normal mode until a predetermined time (in this embodiment, 5 minutes) elapses.

  In the defrost mode, the refrigerant circuit of the heat pump cycle 10 is connected to the compressor 11 (→ the indoor condenser 13 → the bypass passage 15) → the outdoor heat exchanger 16 (→ the three-way valve) as shown by the hatched arrows in FIG. 20) → Accumulator 19 → Hot gas cycle in which the refrigerant circulates in the order of compressor 11.

  In the defrosting mode, the operation of the air mix door 34 is controlled so that the total air volume of the blown air bypasses the indoor condenser 13, so that the refrigerant hardly dissipates heat in the indoor condenser 13. For this reason, blown air is not heated by the indoor condenser 13.

  Therefore, in the heat pump cycle 10 in the defrosting mode, the high-pressure and high-temperature refrigerant compressed by the compressor 11 flows into the outdoor heat exchanger 16 and dissipates heat. Thereby, the outdoor heat exchanger 16 is heated and defrosting of the outdoor heat exchanger 16 is realized. The refrigerant that has flowed out of the outdoor heat exchanger 16 flows into the accumulator 19 through the three-way valve 20. The gas-phase refrigerant that has been gas-liquid separated by the accumulator 19 is sucked into the compressor 11.

  The vehicle air conditioner 1 according to the present embodiment operates as described above to realize cooling, heating, and dehumidifying heating in the passenger compartment, and when the frost is generated in the outdoor heat exchanger 16, it is removed. The outdoor heat exchanger 16 can be defrosted by switching to the frost mode.

  Furthermore, in the vehicle air conditioner 1 of the present embodiment, the refrigerant circuit control means 50c that controls the operation of the on-off valve 15a and the three-way valve 20 is an outdoor heat exchanger in control steps S62 and S65 that constitute the frosting determination means. When it is determined that frost formation has occurred in 16 and pre-air conditioning is being executed (including when the pre-air conditioning is started), the refrigerant circuit is switched to the defrost mode refrigerant circuit.

  In other words, the refrigerant circuit control means 50c of the present embodiment, when it is determined that frost formation has occurred in the outdoor heat exchanger 16 in the control steps S62 and S65, Switching to the refrigerant circuit in the defrosting mode is prohibited.

  Therefore, the defrosting of the outdoor heat exchanger 16 of the present embodiment is performed when pre-air conditioning is performed before the occupant gets into the vehicle. Thereby, it can suppress that a passenger | crew's feeling of heating deteriorates because the heat pump cycle 10 is switched to the refrigerant circuit of a defrost mode.

  Moreover, in the vehicle air conditioner of this embodiment, as explained in control step S61, when the outdoor unit temperature Tout of the outdoor heat exchanger 16 is lower than the predetermined reference temperatures KT1 to KT3, the outdoor unit It is determined that frost formation has occurred in the heat exchanger 16. Each reference temperature has a relationship of KT1 <KT2 <KT3.

  Further, in control step S63, when the frost level FL (specifically, FL_OLD) is 1 or more, it is determined whether or not pre-air conditioning is started. In control step S65, the frost level FL is determined. Is equal to or greater than 2, it is determined whether pre-air conditioning is in progress.

  That is, in this embodiment, it is determined whether or not frost is generated in the outdoor heat exchanger 16 using a low reference temperature (high frost level FL) with the passage of time from the start of pre-air conditioning. It will be. For this reason, it becomes difficult to determine that frost formation has occurred in the outdoor heat exchanger 16 as time elapses from the start of pre-air conditioning.

  Accordingly, in the control step S6, the operation mode is hardly determined to be the defrosting mode as time elapses from the start of the pre-air conditioning (that is, as time until the passenger gets into the vehicle approaches). As a result, it is possible to suppress the operation in the defrost mode immediately before the occupant gets into the vehicle, and to suppress the deterioration of the feeling of heating when the occupant gets into the vehicle interior.

  Further, in the vehicle air conditioner 1 of the present embodiment, as described in the control step S76, the outdoor unit temperature Tout is the first reference temperature KT1 (specifically, −20) with the frost level FL set to 3. When the temperature is lower than (° C.), the upper limit value f (outdoor heat exchanger) of the blower level is lowered.

  Therefore, even if it is determined that frost formation has occurred in the outdoor heat exchanger 16 and pre-air conditioning is not being performed, the refrigerant in the indoor condenser 13 is reduced by reducing the blowing capacity of the blower 32. The amount of heat release can be reduced, the amount of refrigerant absorbed in the outdoor heat exchanger 16 can be reduced, and the progress of frost formation on the outdoor heat exchanger 16 can be delayed.

  Thereby, when pre-air-conditioning is not executed, that is, when the occupant is in the vehicle compartment, not only can the operation in the defrost mode be suppressed, but also in the normal mode (heating mode). Therefore, it is possible to suppress the occurrence of fogging on the vehicle window glass and to ensure the visibility (safety) of the occupant.

  As described above, according to the vehicle air conditioner 1 of the present embodiment, the reference temperatures KT1 to KT3 for determining that frost formation has occurred are reduced stepwise, and frost formation is started at the start of pre-air conditioning. Switch to defrost mode when level FL = 1, switch to defrost mode when frosting level FL = 2 during pre-air conditioning, and frost after pre-air conditioning ends When the level FL = 3, the blowing capacity of the blower 32 is reduced. As a result, when the occupant gets into the vehicle interior, the outdoor heat exchanger 16 is defrosted, so that the temperature of the conditioned air can be effectively suppressed.

  Further, in the vehicle air conditioner 1 of the present embodiment, as described in the control step S11, the remaining charge SOC of the battery B is equal to or less than the reference charged remaining charge KSOC even during pre-air conditioning. When sufficient electric power is not supplied from the external power source, the air conditioning stop flag f (A / C) is set to 1 in control step S120, and the operation of the vehicle air conditioner 1 is stopped. Thereby, the passenger can be prompted to charge the battery B.

  Further, even during pre-air conditioning, when the economy switch is turned on, as explained in control step S123, the electric power that can be consumed by various electric components of the vehicle air conditioner 1 The use permission power f (POWER), which is the upper limit value, is reduced. Thereby, reduction of the energy consumed for the air conditioning of a vehicle interior can be aimed at.

(Other embodiments)
The present invention is not limited to the above-described embodiment, and can be variously modified as follows without departing from the spirit of the present invention.

  (1) In the above-described embodiment, an example in which an electric compressor is employed as the compressor 11 has been described. However, the format of the compressor 11 is not limited to this. For example, you may employ | adopt the compressor 11 which obtains a driving force from an engine via a belt, an electromagnetic clutch, etc. Therefore, application of the vehicle air conditioner 1 of the present invention is not limited to an electric vehicle.

  For example, a normal vehicle that travels by obtaining a driving force for traveling from an internal combustion engine (engine), a so-called hybrid vehicle that obtains a driving force for traveling from both the internal combustion engine and the traveling electric motor, and an external device when the vehicle is stopped You may apply to what is called a plug-in hybrid vehicle which can charge the battery B with the electric power supplied from a power supply (commercial power supply).

  In addition, in a vehicle equipped with an engine, in addition to the indoor condenser 13, a heating heat exchanger (heater core) for heating the blown air using engine cooling water as a heat source may be provided as auxiliary heating means for the blown air.

  (2) In the above-described embodiment, the heat pump cycle 10 configured to be able to switch the refrigerant circuit in the heating mode, the cooling mode, the dehumidifying heating mode, and the defrosting mode has been described. The present invention is applicable to a vehicle air conditioner including a heat pump cycle configured to be able to switch between a circuit and a refrigerant circuit in a defrost mode.

  Moreover, in the above-described embodiment, the example of switching to the refrigerant circuit in the defrost mode when defrosting the outdoor heat exchanger 16 has been described. However, when the outdoor heat exchanger 16 is defrosted, the refrigerant circuit in the cooling mode is described. You may make it switch to.

  (3) In the above-described embodiment, once switched to the defrost mode, an example in which the operation in the defrost mode is continued until a predetermined time elapses has been described. Switching to is not limited to this. For example, the defrost mode may be switched to the normal mode when the outdoor unit temperature Tout becomes equal to or higher than a predetermined switching reference temperature.

DESCRIPTION OF SYMBOLS 10 Heat pump cycle 11 Compressor 13 Indoor condenser 15a On-off valve (refrigerant circuit switching means)
16 Outdoor heat exchanger 20 Three-way valve (refrigerant circuit switching means)
50c Refrigerant circuit control means

Claims (3)

A compressor (11) that compresses and discharges the refrigerant, an indoor condenser (13) that exchanges heat between the refrigerant and the blown air blown into the vehicle interior, and an outdoor heat exchanger (16) that exchanges heat between the refrigerant and the outside air And a heat pump cycle (10) having refrigerant circuit switching means (15a, 20) for switching the refrigerant circuit through which the refrigerant circulates,
When the vehicle interior is heated, the refrigerant circuit switching means (15a, 20) causes the refrigerant discharged from the compressor (11) to flow into the indoor condenser (13) and the outdoor heat exchange. When the outdoor heat exchanger (16) is defrosted by switching to a heating mode refrigerant circuit that evaporates the refrigerant in the cooler (16), the refrigerant discharged from the compressor (11) is used as the outdoor heat. It is configured to switch to a refrigerant circuit in a defrost mode that flows into the exchanger (16),
Further, the vehicle air conditioner configured to be able to perform pre-air conditioning that starts air conditioning in the passenger compartment before the occupant enters the vehicle,
Frosting determination means (S62, S65) for determining that frost formation has occurred in the outdoor heat exchanger (16);
Refrigerant circuit control means (50c) for controlling the operation of the refrigerant circuit switching means (15a, 20),
When the refrigerant circuit control means (50c) determines that the frost formation has occurred by the frost formation determination means (S62, S65) and the pre-air conditioning is being executed, the refrigerant circuit control means (50c) The operation of the refrigerant circuit switching means (15a, 20) is controlled so as to switch to the refrigerant circuit,
When the outdoor temperature (Tout) of the outdoor heat exchanger (16) is lower than a predetermined reference temperature (KT1 to KT3), the frost determination means (S62, S65) At the start of the pre-air conditioning, it is determined whether or not the frost has occurred based on the value stored when the previous vehicle system stopped,
As the reference temperature (KT1~KT3), before Symbol the reference temperature used during the execution of the pre-air conditioning (KT2, KT3) is, the criteria used in determining on the basis of the value stored at the previous vehicle system stop A vehicle air conditioner characterized in that it is set to a value lower than the temperature (KT1, KT2) . A compressor (11) that compresses and discharges the refrigerant, an indoor condenser (13) that exchanges heat between the refrigerant and the blown air blown into the vehicle interior, and an outdoor heat exchanger (16) that exchanges heat between the refrigerant and the outside air And a heat pump cycle (10) having refrigerant circuit switching means (15a, 20) for switching the refrigerant circuit through which the refrigerant circulates,
When the vehicle interior is heated, the refrigerant circuit switching means (15a, 20) causes the refrigerant discharged from the compressor (11) to flow into the indoor condenser (13) and the outdoor heat exchange. When the outdoor heat exchanger (16) is defrosted by switching to a heating mode refrigerant circuit that evaporates the refrigerant in the cooler (16), the refrigerant discharged from the compressor (11) is used as the outdoor heat. It is configured to switch to a refrigerant circuit in a defrost mode that flows into the exchanger (16),
Further, the vehicle air conditioner configured to be able to perform pre-air conditioning that starts air conditioning in the passenger compartment before the occupant enters the vehicle,
Frosting determination means (S62, S65) for determining that frost formation has occurred in the outdoor heat exchanger (16);
Refrigerant circuit control means (50c) for controlling the operation of the refrigerant circuit switching means (15a, 20),
When the refrigerant circuit control means (50c) determines that the frost formation has occurred by the frost formation determination means (S62, S65) and the pre-air conditioning is being executed, the refrigerant circuit control means (50c) The operation of the refrigerant circuit switching means (15a, 20) is controlled so as to switch to the refrigerant circuit ,
When the outdoor temperature (Tout) of the outdoor heat exchanger (16) is lower than a predetermined reference temperature (KT1 to KT3), the frosting determination means (S62, S65) is configured to perform the outdoor heat exchange. It is determined that frosting has occurred in the vessel (16),
The vehicle air conditioner is characterized in that the reference temperature (KT1 to KT3) is determined to become a low temperature with an elapsed time from the start of the pre-air conditioning. A blower (32) for blowing the blown air toward the vehicle interior;
A blower control means (50b) for controlling the operation of the blower (32),
The blower control means (50b) determines that the frost formation has occurred by the frost formation determination means (S62, S65) and when the pre-air conditioning is not being executed, The air conditioner for vehicles according to claim 1 or 2, wherein the air blowing capacity is lowered.

Images