JP6390431B2 - Refrigeration cycle equipment - Google Patents

Description

  The present invention relates to a refrigeration cycle apparatus applied to an air conditioner that performs dehumidifying heating of a space to be air-conditioned.

  Conventionally, Patent Document 1 discloses a refrigeration cycle apparatus applied to a vehicle air conditioner that performs dehumidification heating in a vehicle interior that is an air conditioning target space. The refrigeration cycle apparatus of Patent Document 1 includes an outdoor heat exchanger that exchanges heat between refrigerant and outside air, an indoor evaporator that exchanges heat between refrigerant flowing out of the outdoor heat exchanger and blown air blown into the vehicle interior, and An indoor condenser that exchanges heat between the high-pressure refrigerant discharged from the compressor and the blown air after passing through the indoor evaporator is provided.

  In the dehumidifying and heating mode for dehumidifying and heating the passenger compartment, the refrigerant is circulated in the order of the compressor, the indoor condenser, the pressure reducing device, the outdoor heat exchanger, the indoor evaporator, and the compressor, and is cooled by the indoor evaporator. The blown air dehumidified in this way is reheated by the indoor condenser and blown to the air-conditioning target space. That is, in the refrigeration cycle apparatus of Patent Document 1, dehumidification heating of the air-conditioning target space is realized with a simple cycle configuration in which an outdoor heat exchanger and an indoor evaporator are connected in series.

Japanese Patent No. 3331765

  By the way, in the refrigeration cycle apparatus of patent document 1, in order to suppress frost formation of the indoor evaporator, the refrigerant evaporation temperature in the indoor evaporator is set higher than a predetermined reference frost suppression temperature (3 ° C. in patent document 1). It is adjusted to a high temperature. For this reason, in the cycle configuration in which the outdoor heat exchanger and the indoor evaporator are connected in series to the refrigerant flow as in the refrigeration cycle apparatus of Patent Document 1, the refrigerant evaporation temperature in the outdoor heat exchanger is also the reference frost formation. It tends to be higher than the suppression temperature.

  Therefore, when the outside air temperature is low (for example, when the outside air temperature is 10 ° C. or lower), the temperature difference between the refrigerant evaporation temperature and the outside air temperature in the outdoor heat exchanger is reduced, and the refrigerant is The amount of heat absorbed from the heat will decrease. As a result, in the refrigeration cycle apparatus of Patent Document 1, in the dehumidifying and heating mode, the amount of heat radiation that the refrigerant can radiate to the blown air is reduced in the indoor condenser, and the heating capacity of the blown air may be reduced There is.

  An object of this invention is to provide the refrigerating-cycle apparatus which can suppress the fall of the heating capability of blowing air at the time of dehumidification heating mode, without causing complication of a cycle structure in view of the said point.

The present invention has been devised to achieve the above object, and in the invention described in claim 1, a refrigeration cycle apparatus applied to an air conditioner,
A compressor (11) that compresses and discharges the refrigerant, and a heating means (12, 70) that heats the air blown into the air-conditioning target space by dissipating the refrigerant discharged from the compressor (11), Outdoors for exchanging heat between the high pressure reducing means (13, 13a) for reducing the pressure of the refrigerant flowing out of the heating means (12, 70) and the refrigerant decompressed by the high pressure reducing means (13, 13a) A heat exchanger (14), and a cooling means (17) for evaporating the refrigerant flowing out of the outdoor heat exchanger (14) and cooling the blown air,
The heating means (12, 70) heats the blown air cooled by the cooling means (17) in the dehumidifying heating mode for performing dehumidifying heating of the air-conditioning target space,
The outdoor heat exchanger (14) evaporates the refrigerant in the dehumidifying heating mode,
As the refrigerant, a non-azeotropic refrigerant mixture in which a saturation temperature increases with an increase in dryness is employed.

  According to this, in the dehumidifying heating mode, the compressor (11) → the heating means (12, 70) → the high pressure side decompression means (13, 13a) → the outdoor heat exchanger (14) → the cooling means (17) → the compression In a simple cycle configuration in which the refrigerant is circulated in the order of the machine (11), the blown air cooled and dehumidified by the cooling means (17) is reheated by the heating means (12, 70), and Dehumidification heating can be performed.

  Furthermore, since a non-azeotropic refrigerant mixture whose saturation temperature increases as the dryness increases is employed as the refrigerant, the refrigerant evaporation temperature in the outdoor heat exchanger (14) connected to the refrigerant flow upstream side is It can be made lower than the refrigerant evaporation temperature in the cooling means (17) connected to the downstream side of the refrigerant flow.

  Therefore, even when the outdoor temperature is low, the temperature difference between the refrigerant evaporating temperature and the outdoor temperature in the outdoor heat exchanger (14) is suppressed, and the refrigerant is stored in the outdoor heat exchanger (14). A decrease in the amount of heat absorbed from the outside air can be suppressed. As a result, it is possible to suppress a decrease in the amount of heat radiation that can be radiated from the refrigerant to the blown air by the heating means (12, 70).

  That is, according to the invention described in the present claims, it is possible to suppress a decrease in the heating capacity of the blown air during the dehumidifying heating mode without causing a complicated cycle configuration.

  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.

It is a whole block diagram of the vehicle air conditioner which shows the refrigerant | coolant flow of the air_conditioning | cooling mode of the refrigerating-cycle apparatus of 1st Embodiment. It is a whole block diagram of the vehicle air conditioner which shows the refrigerant | coolant flow of the heating mode of the refrigerating-cycle apparatus of 1st Embodiment. It is a whole block diagram of the vehicle air conditioner which shows the refrigerant | coolant flow in the dehumidification heating mode of the refrigeration cycle apparatus of 1st Embodiment. It is a block diagram which shows the electric control part of the vehicle air conditioner of 1st Embodiment. It is a Mollier diagram which shows the change of the state of the refrigerant | coolant in the refrigerating-cycle apparatus of the dehumidification heating mode of 1st Embodiment. It is a whole block diagram of the vehicle air conditioner which shows the refrigerant | coolant flow of the air_conditioning | cooling mode of the refrigerating-cycle apparatus of 2nd Embodiment. It is a whole block diagram of the vehicle air conditioner which shows the refrigerant | coolant flow of the heating mode of the refrigerating-cycle apparatus of 2nd Embodiment. It is a whole block diagram of the vehicle air conditioner which shows the refrigerant | coolant flow in the dehumidification heating mode of the refrigerating-cycle apparatus of 2nd Embodiment. It is a whole block diagram of the vehicle air conditioner of 3rd Embodiment.

(First embodiment)
1st Embodiment of this invention is described using FIGS. In the present embodiment, the refrigeration cycle apparatus 10 according to the present invention is applied to a vehicle air conditioner 1 for an electric vehicle that obtains a driving force for vehicle traveling from a traveling electric motor. The refrigeration cycle apparatus 10 fulfills a function of cooling or heating the air blown into the vehicle interior, which is the air-conditioning target space, in the vehicle air conditioner 1.

  Further, the refrigeration cycle apparatus 10 of the present embodiment includes a cooling mode refrigerant circuit (see FIG. 1) that cools the blown air to cool the vehicle interior, and a heating mode refrigerant circuit that heats the blown air and heats the vehicle interior. The refrigerant circuit (see FIG. 3) in the dehumidifying and heating mode in which the blown air that has been cooled and dehumidified is reheated to perform dehumidifying heating in the passenger compartment (see FIG. 3) can be switched.

  In the refrigeration cycle apparatus 10, a non-azeotropic refrigerant mixture is adopted as the refrigerant. The non-azeotropic refrigerant mixture is a refrigerant in which a plurality of types of refrigerants are mixed, and has a property that the saturation temperature changes with a phase change. More specifically, in the present embodiment, a non-azeotropic refrigerant mixture that mainly includes R1234yf and R32 and whose saturation temperature rises as the dryness increases is employed.

  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.

  Among the components of the refrigeration cycle apparatus 10, the compressor 11 is disposed in the vehicle bonnet, and sucks, compresses, and discharges the refrigerant in the refrigeration cycle apparatus 10. The compressor 11 of this embodiment is configured as an electric compressor that drives a fixed capacity type compression mechanism with a fixed discharge capacity by an electric motor. Specifically, various compression mechanisms such as a scroll type compression mechanism and a vane type compression mechanism can be employed as the compression mechanism.

  The operation (rotation speed) of the electric motor is controlled by a control signal output from the air conditioning control device 40 described later, and either an AC motor or a DC motor may be adopted. And the refrigerant | coolant discharge capability of a compression mechanism is changed because the air-conditioning control apparatus 40 controls the rotation speed of an electric motor.

  The refrigerant inlet side of the indoor condenser 12 is connected to the discharge port of the compressor 11. The indoor condenser 12 is disposed in a casing 31 of an indoor air conditioning unit 30 to be described later. In the heating mode and the dehumidifying heating mode, the indoor condenser 12 radiates the refrigerant discharged from the compressor 11 and blows air by the radiated heat. It is a heating means for heating air.

  More specifically, the indoor condenser 12 is a heating heat exchanger that heats the blown air by exchanging heat between the high-temperature and high-pressure refrigerant discharged from the compressor 11 and the blown air in the heating mode or the like. .

  An inlet side of the first expansion valve 13 is connected to the refrigerant outlet of the indoor condenser 12. The first expansion valve 13 is a high-stage decompression unit that decompresses the refrigerant flowing out of the indoor condenser 12 during the heating mode and the dehumidifying heating mode. More specifically, the first expansion valve 13 includes a valve body configured to be able to change the throttle opening, and an electric actuator including a stepping motor that changes the throttle opening of the valve body. Variable aperture mechanism.

  Further, the first expansion valve 13 is a variable throttle mechanism with a full opening function that functions as a simple refrigerant passage with almost no refrigerant decompression effect by fully opening the throttle opening. The operation of the first expansion valve 13 is controlled by a control signal (control pulse) output from the air conditioning control device 40.

  The outlet of the first expansion valve 13 is connected to the refrigerant inlet side of the outdoor heat exchanger 14. The outdoor heat exchanger 14 is disposed on the front side of the vehicle in the vehicle bonnet, and exchanges heat between the refrigerant flowing inside the vehicle and outside air (outside air) blown from a blower fan (not shown). The blower fan is an electric blower whose number of rotations (blowing capacity) is controlled by a control voltage output from the air conditioning control device 40.

  A refrigerant inlet of the first three-way joint 15 is connected to the refrigerant outlet of the outdoor heat exchanger 14. The first three-way joint 15 may be formed by joining a plurality of pipes, or may be formed by providing a plurality of refrigerant passages in a metal block or a resin block. Further, in the first three-way joint 15, one of the three refrigerant inflow / outflow ports is used as the refrigerant inflow port, and the remaining two are used as the refrigerant outflow ports.

  One refrigerant outlet of the first three-way joint 15 is connected to the inlet side of the second expansion valve 16. The second expansion valve 16 is a low-stage decompression unit that decompresses the refrigerant flowing out of the outdoor heat exchanger 14 and flows it out to the indoor evaporator 17 side in the dehumidifying heating mode. The basic configuration of the second expansion valve 16 is the same as that of the first expansion valve 13.

  Furthermore, the second expansion valve 16 not only fully opens the refrigerant passage from the first three-way joint 15 to the indoor evaporator 17 when the throttle opening is fully opened, but also fully closes the throttle opening and applies the refrigerant. It consists of a variable throttle mechanism with a fully closed function that closes the passage.

  Accordingly, the second expansion valve 16 includes a refrigerant circuit that communicates one refrigerant outlet of the first three-way joint 15 and the refrigerant inlet of the indoor evaporator 17, and one refrigerant outlet and the room evaporation of the first three-way joint 15. The refrigerant circuit that does not communicate with the refrigerant inlet of the vessel 17 can be switched. That is, the second expansion valve 16 of the present embodiment also has a function as refrigerant circuit switching means.

  The outlet of the second expansion valve 16 is connected to the refrigerant inlet side of the indoor evaporator 17. The indoor evaporator 17 is disposed in the casing 31 of the indoor air conditioning unit 30 on the upstream side of the blower air flow of the indoor condenser 12, and flows out of the outdoor heat exchanger 14 in the cooling mode and the dehumidifying heating mode. It is a cooling means for evaporating the refrigerant and cooling the blown air.

  More specifically, the indoor evaporator 17 causes the low-pressure refrigerant that has flowed out of the outdoor heat exchanger 14 to evaporate by exchanging heat with the blown air before passing through the indoor condenser 12 in the cooling mode or the like, and absorbs heat to the low-pressure refrigerant. It is a heat exchanger for cooling which cools ventilation air by exhibiting an effect | action.

  One refrigerant inlet of the second three-way joint 18 is connected to the refrigerant outlet side of the indoor evaporator 17. The basic configuration of the second three-way joint 18 is the same as that of the first three-way joint 15. In the second three-way joint 18, two of the three refrigerant inlets / outlets are used as refrigerant inlets, and the remaining one is used as a refrigerant outlet. The other refrigerant outlet of the first three-way joint 15 is connected to the other refrigerant inlet of the second three-way joint 18 via a heating bypass passage 19.

  A heating on / off valve 20 that opens and closes the heating bypass passage 19 is disposed in the heating bypass passage 19. The heating on-off valve 20 is an electromagnetic valve that is opened and closed by a control voltage output from the air-conditioning control device 40.

  Accordingly, the heating on-off valve 20 includes a refrigerant circuit that connects the other refrigerant outlet of the first three-way joint 15 and the other refrigerant inlet of the second three-way joint 18, and the other refrigerant flow of the first three-way joint 15. This is a refrigerant circuit switching means for switching a refrigerant circuit that does not allow communication between the outlet and the other refrigerant inlet of the second three-way joint 18.

  The refrigerant outlet of the second three-way joint 18 is connected to the inlet side of the accumulator 21. The accumulator 21 is a gas-liquid separation unit that separates the gas-liquid of the refrigerant that has flowed into the accumulator and stores excess refrigerant in the cycle, and causes the separated gas-phase refrigerant to flow out downstream. The suction port side of the compressor 11 is connected to the gas phase refrigerant outlet of the accumulator 21.

  Next, the indoor air conditioning unit 30 will be described. The indoor air conditioning unit 30 is for blowing out the blown air whose temperature has been adjusted by the refrigeration cycle apparatus 10 into the vehicle interior, and is disposed inside the instrument panel (instrument panel) at the forefront of the vehicle interior. Furthermore, the indoor air conditioning unit 30 is configured by housing the blower 32, the indoor evaporator 17, the indoor condenser 12, and the like in a casing 31 that forms an outer shell thereof.

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

  The inside / outside air switching device 33 continuously 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, so that the air volume of the inside air and the air volume of the outside air are adjusted. The air volume ratio is continuously changed. The inside / outside air switching door is driven by an electric actuator for the inside / outside air switching door, and the operation of the electric actuator is controlled by a control signal output from the air conditioning control device 40.

  On the downstream side of the blown air flow of the inside / outside air switching device 33, a blower (blower) 32 is disposed as a blowing means for blowing the air sucked through the inside / outside air switching device 33 toward the vehicle interior. 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 40.

  On the downstream side of the blower air flow of the blower 32, the indoor evaporator 17 and the indoor condenser 12 are arranged in this order with respect to the flow of the blown air. In other words, the indoor evaporator 17 is disposed upstream of the blower air flow with respect to the indoor condenser 12. Further, in the casing 31, a cold air bypass passage 35 is formed in which the blown air that has passed through the indoor evaporator 17 bypasses the indoor condenser 12 and flows downstream.

  An air mix door 34 is arranged on the downstream side of the blower air flow of the indoor evaporator 17 and on the upstream side of the blower air flow of the indoor condenser 12. The air mix door 34 of this embodiment is a ventilation path switching unit that switches between a ventilation path that guides the blown air that has passed through the indoor evaporator 17 to the indoor condenser 12 side and a ventilation path that leads to the cold air bypass path 35 side.

  The air mix door 34 can also function as an air volume ratio adjusting unit that adjusts an air volume ratio that allows the indoor condenser 12 to pass through the blown air that has passed through the indoor evaporator 17. The air mix door 34 is driven by an electric actuator for driving the air mix door, and the operation of the electric actuator is controlled by a control signal output from the air conditioning control device 40.

  The blower air heated by the indoor condenser 12 or the blown air not heated by the indoor condenser 12 through the cold air bypass passage 35 flows into the downstream side of the blower air flow of the indoor condenser 12 (not shown). An inflow space is provided. Furthermore, the opening hole which blows off the blowing air (air-conditioning wind) which flowed into the inflow space to the vehicle interior which is an air-conditioning object space is arrange | positioned at the most downstream part of the ventilation air flow of the casing 31.

  Specifically, the opening hole includes a face opening hole that blows air-conditioned air toward the upper body of the passenger in the passenger compartment, a foot opening hole that blows air-conditioned air toward the feet of the passenger, and an inner surface of the front window glass of the vehicle. A defroster opening hole (both not shown) for blowing the conditioned air toward is provided.

  The air flow downstream of these face opening holes, foot opening holes, and defroster opening holes is connected to the face air outlet, foot air outlet, and defroster air outlet provided in the vehicle interior via ducts that form air passages, respectively. Neither is shown).

  Further, on the upstream side of the air flow of the face opening hole, foot opening hole, and defroster opening hole, a face door for adjusting the opening area of the face opening hole, a foot door for adjusting the opening area of the foot opening hole, and a defroster opening, respectively. A defroster door (both not shown) for adjusting the opening area of the hole is disposed.

  These face doors, foot doors, and defroster doors constitute opening hole mode switching means for switching the opening hole mode, and are linked to an electric actuator for driving the outlet mode door via a link mechanism or the like. And rotated. The operation of this electric actuator is also controlled by a control signal output from the air conditioning controller 40.

  Specific examples of the air outlet mode switched by the air outlet mode switching means include a face mode, a bi-level mode, a foot mode, and a foot defroster mode.

  The face mode is an air outlet mode in which the face air outlet is fully opened and air is blown out from the face air outlet toward the upper body of the passenger in the passenger compartment. The bi-level mode is an air outlet mode in which both the face air outlet and the foot air outlet are opened and air is blown toward the upper body and the feet of the passengers in the passenger compartment. The foot mode is a blow-out mode in which the foot blow-out opening is fully opened and the defroster blow-out opening is opened by a small opening so that air is mainly blown out from the foot blow-out opening. The foot defroster mode is an air outlet mode in which the foot air outlet and the defroster air outlet are opened to the same extent and air is blown out from both the foot air outlet and the defroster air outlet.

  In addition, the defroster mode in which the occupant manually operates a blow mode switching switch provided on the operation panel 60, which will be described later, fully opens the defroster outlet and blows air from the defroster outlet to the inner surface of the front windshield of the vehicle. it can.

  Next, the electric control unit of the present embodiment will be described with reference to FIG. The air conditioning control device 40 includes a known microcomputer including a CPU, a ROM, a RAM, and the like and peripheral circuits thereof. Then, various calculations and processes are performed based on the air conditioning control program stored in the ROM, and the compressor 11, the first expansion valve 13, the second expansion valve 16, and the heating on-off valve connected to the output side thereof. 20. Control the operation of various air conditioning control devices such as the blower 32.

  Further, on the input side of the air conditioning control device 40, an inside air sensor 51, an outside air sensor 52, a solar radiation sensor 53, a condenser inlet side temperature sensor 54a, a condenser outlet side temperature sensor 54b, a high pressure side pressure sensor 55, and an evaporator inlet side. A group of sensors for air conditioning control such as a temperature sensor 56a, an evaporator outlet side temperature sensor 56b, and a blown air temperature sensor 57 are connected. Then, detection signals detected by these sensor groups for air conditioning control are input to the air conditioning control device 40.

  The inside air sensor 51 is an inside air temperature detecting means for detecting a passenger compartment temperature (inside air temperature) Tr. The outside air sensor 52 is an outside air temperature detecting means for detecting a vehicle compartment outside temperature (outside air temperature) Tam. The solar radiation sensor 53 is a solar radiation amount detecting means for detecting the solar radiation amount As irradiated into the vehicle interior.

  The condenser inlet side temperature sensor 54a is a condenser inlet side temperature detecting means for detecting the condenser inlet side temperature Tcin of the refrigerant discharged from the compressor 11 and flowing into the indoor condenser 12. The condenser outlet side temperature sensor 54b is a condenser outlet side temperature detecting means for detecting the condenser outlet side temperature Tcout of the refrigerant flowing out from the indoor condenser 12. The high-pressure side pressure sensor 55 is high-pressure side pressure detection means for detecting the pressure (high-pressure side refrigerant pressure) Pd of the refrigerant on the outlet side of the indoor condenser 12.

  The evaporator inlet side temperature sensor 56 a is an evaporator inlet side temperature detecting means for detecting the evaporator inlet side temperature Tein of the refrigerant flowing into the indoor evaporator 17. The evaporator outlet side temperature sensor 56 b is an evaporator outlet side temperature detecting means for detecting the evaporator outlet side temperature Teout of the refrigerant flowing out from the indoor evaporator 17.

  The blown air temperature sensor 57 is a blown air temperature detection unit that detects a blown air temperature TAV blown from the inflow space into the vehicle interior. When the blowing air temperature detection means is abolished, the blowing air temperature TAV is calculated based on the condenser inlet side temperature Tcin, the condenser outlet side temperature Tco, the evaporator inlet side temperature Tein, the evaporator outlet side temperature Teout, and the like. May be adopted.

  Furthermore, an operation panel 60 disposed near the instrument panel in the front of the passenger compartment is connected to the input side of the air conditioning control device 40, and operation signals of various air conditioning operation switches provided on the operation panel 60 are input. The

  Specifically, various air conditioning operation switches of the operation panel 60 include an auto switch for setting or canceling the automatic control operation of the vehicle air conditioner 1, and a cooling switch (A / C switch) for requesting cooling of the vehicle interior. There are provided an air volume setting switch for manually setting the air volume of the blower 32, a temperature setting switch for setting the vehicle interior set temperature Tset, which is a target temperature in the vehicle interior, a blow mode switching switch for manually setting the blow mode, and the like.

  The air-conditioning control device 40 is configured integrally with control means for controlling various air-conditioning control devices connected to the output side of the air-conditioning control device 40, but is configured to control the operation of each air-conditioning control device (hardware and Software) constitutes a control means for controlling the operation of each air conditioning control device.

  For example, in the present embodiment, the configuration for controlling the operation (refrigerant discharge capability) of the compressor 11 constitutes the discharge capability control means 40a, and the configuration for controlling the operation (high-stage throttle opening) of the first expansion valve 13. Constitutes the high stage side throttle opening degree control means 40b, and the configuration for controlling the operation (low stage side throttle opening degree) of the second expansion valve 16 constitutes the low stage side throttle opening degree control means 40c.

  Of course, the discharge capacity control means 40a, the high stage side throttle opening degree control means 40b, the low stage side throttle opening degree control means 40c, etc. may be configured as a separate control device for the air conditioning control device 40.

  Next, the operation of the vehicle air conditioner 1 of the present embodiment having the above configuration will be described. As described above, in the vehicle air conditioner 1 of the present embodiment, the operation in the cooling mode, the heating mode, and the dehumidifying heating mode can be switched. Switching between these operation modes is performed by executing an air conditioning control program stored in the air conditioning control device 40 in advance.

  This air conditioning control program is executed when the auto switch of the operation panel 60 is turned on. More specifically, in the main routine of the air conditioning control program, the detection signals of the sensor groups 51 to 57 for air conditioning control, the operation signals of the operation panel 60, and the like are read. And based on the read detection signal and operation signal, the target blowing temperature TAO which is the target temperature of the blowing air which blows off into the vehicle interior is calculated.

This target blowing temperature TAO is calculated by the following formula F1.
TAO = Kset × Tset−Kr × Tr−Kam × Tam−Ks × As + C (F1)
Here, Tset is the vehicle interior set temperature set by the temperature setting switch, Tr is the vehicle interior temperature (inside air temperature) detected by the inside air sensor 51, and Tam is the outside air temperature detected by the outside air sensor 52. Yes, As is the amount of solar radiation detected by the solar radiation sensor 53. Kset, Kr, Kam, Ks are control gains, and C is a correction constant.

  Further, when the cooling switch of the operation panel is turned on and the target blowout temperature TAO is lower than the predetermined cooling reference temperature α, the operation in the cooling mode is executed. Further, when the cooling switch is turned on and the target blowing temperature TAO is equal to or higher than the cooling reference temperature α, the operation in the dehumidifying heating mode is executed. When the cooling switch is not turned on, the operation in the heating mode is executed. Below, the operation | movement in each operation mode is demonstrated.

(A) Cooling mode In the cooling mode, the air conditioning control device 40 opens the first expansion valve 13 fully, places the second expansion valve 16 in a throttle state that exerts a refrigerant decompression action, and closes the heating on-off valve 20. Thereby, in the cooling mode, as shown by the solid line arrow in FIG. 1, the compressor 11 → the indoor condenser 12 → (the first expansion valve 13 →) the outdoor heat exchanger 14 → the second expansion valve 16 → the indoor evaporator 17. A refrigeration cycle in which the refrigerant is circulated in the order of the accumulator 21 → the suction port of the compressor 11 is configured.

  Further, the air-conditioning control device 40 determines the operating states of the various control target devices (control signals to be output to the various control target devices) based on the target blowing temperature TAO, the detection signal of the sensor group, and the like with the configuration of the refrigerant circuit. To do.

  For example, the refrigerant discharge capacity of the compressor 11 (control signal output to the electric motor of the compressor 11) is determined as follows. First, the target refrigerant evaporation temperature TEO in the indoor evaporator 17 is determined on the basis of the target outlet temperature TAO with reference to a control map stored in the air conditioning controller 40 in advance.

  More specifically, in this control map, the target refrigerant evaporation temperature TEO is determined to decrease with a decrease in the target outlet temperature TAO. Furthermore, in this control map, in order to suppress frost formation of the indoor evaporator 17, it is determined that the target refrigerant evaporation temperature TEO is equal to or higher than a reference frost formation suppression temperature KTf (for example, 1 ° C.).

  Based on the deviation between the target evaporator outlet temperature TEO and the evaporator inlet side temperature Tein detected by the evaporator temperature sensor, the evaporator inlet side temperature Tein is converted to the target evaporator outlet temperature TEO using a feedback control method. The control signal output to the electric motor of the compressor 11 is determined so as to approach

  For this reason, in this embodiment, the rotation speed (refrigerant discharge capability) of the compressor 11 is increased as the target evaporator outlet temperature TEO decreases, and the compressor 11 rotates as the target evaporator outlet temperature TEO increases. Will reduce the number.

  Further, the throttle opening of the second expansion valve 16 (control signal output to the second expansion valve 16) flows into the second expansion valve 16 with reference to a control map stored in the air conditioning control device 40 in advance. The degree of supercooling of the refrigerant is determined so as to approach the target degree of supercooling determined so that the coefficient of performance (COP) of the cycle approaches the maximum value.

  As for the opening degree of the air mix door 34 (control signal output to the electric actuator for the air mix door 34), the air mix door 34 opens the cold air bypass passage 35 and opens the air after passing through the indoor evaporator 17. Is determined so as to pass through the cold air bypass passage 35.

  In the cooling mode, the opening degree of the air mix door 34 may be controlled so that the blown air temperature TAV detected by the blown air temperature sensor 57 approaches the target blowing temperature TAO.

  Then, the control signal determined as described above is output to various devices to be controlled. After that, until the operation stop of the vehicle air conditioner 1 is requested, the above detection signal and operation signal are read at every predetermined control cycle → the target blowing temperature TAO is calculated → the operating states of various control target devices are determined → control Control routines such as voltage and control signal output are repeated. Such a control routine is repeated in the other operation modes.

  Therefore, in the refrigeration cycle apparatus 10 in the cooling mode, the refrigerant discharged from the compressor 11 flows into the indoor condenser 12. At this time, in the cooling mode, since the air mix door 34 fully opens the cold air bypass passage 35, the refrigerant flowing into the indoor condenser 12 flows out of the indoor condenser 12 without releasing heat to the blown air.

  The refrigerant that has flowed out of the indoor condenser 12 flows into the outdoor heat exchanger 14 through the first expansion valve 13 that is fully open. The refrigerant flowing into the outdoor heat exchanger 14 exchanges heat with the outside air blown from the blower fan and dissipates heat. The refrigerant flowing out of the outdoor heat exchanger 14 flows into the second expansion valve 16 and is decompressed because the heating on-off valve 20 is closed.

  The refrigerant decompressed by the second expansion valve 16 flows into the indoor evaporator 17. The refrigerant flowing into the indoor evaporator 17 absorbs heat from the blown air blown from the blower 32 and evaporates. Thereby, blowing air is cooled. The refrigerant flowing out of the indoor evaporator 17 flows into the accumulator 21 and is separated into gas and liquid. The gas-phase refrigerant separated by the accumulator 21 is sucked into the compressor 11 and compressed again.

  Therefore, in the vehicle air conditioner 1 in the cooling mode, the vehicle interior can be cooled by blowing the blown air cooled by the indoor evaporator 17 into the vehicle interior.

(B) Heating mode
In warm tufts mode, the air conditioning controller 40, the first expansion valve 13 and the throttle state, the second expansion valve 16 is fully closed, opening the heating on-off valve 20. Thereby, in the heating mode, as indicated by the solid line arrow in FIG. 2, the compressor 11 → the indoor condenser 12 → the first expansion valve 13 → the outdoor heat exchanger 14 → the heating bypass passage 19 → the accumulator 21 → the compressor 11. A refrigeration cycle in which the refrigerant is circulated in the order of the suction ports is configured.

  Further, the air-conditioning control device 40 determines the operating states of the various control target devices (control signals to be output to the various control target devices) based on the target blowing temperature TAO, the detection signal of the sensor group, and the like with the configuration of the refrigerant circuit. To do.

  For example, the refrigerant discharge capacity of the compressor 11 (control signal output to the electric motor of the compressor 11) is determined as follows. First, the target condensation temperature TCO in the indoor condenser 12 is determined based on the target outlet temperature TAO with reference to a control map stored in the air conditioning control device 40 in advance. More specifically, in this control map, the target condensing temperature TCO is determined to increase as the target blowing temperature TAO increases.

Further, the condenser average temperature Tca is calculated as shown in Formula F2 below.
Tca = (Tcin + Tcout) / 2 (F2)
Here, Tcin is the condenser inlet side temperature detected by the condenser inlet side temperature sensor 54a, and Tcout is the condenser outlet side temperature detected by the condenser outlet side temperature sensor 54b.

  Then, based on the deviation between the target condensation temperature TCO and the condenser average temperature Tca, the feedback control method is used to output the condenser average temperature Tca to the electric motor of the compressor 11 so as to approach the target condensation temperature TCO. A control signal is determined. For this reason, in this embodiment, the rotation speed (refrigerant discharge capability) of the compressor 11 is increased as the target condensation temperature TCO increases, and the rotation speed of the compressor 11 is decreased as the target condensation temperature TCO decreases. It will be.

  Further, the throttle opening degree of the first expansion valve 13 (control signal output to the first expansion valve 13) flows into the first expansion valve 13 with reference to a control map stored in the air conditioning control device 40 in advance. The degree of supercooling of the refrigerant is determined so as to approach the target degree of supercooling determined so that the coefficient of performance (COP) of the cycle approaches the maximum value.

  As for the opening degree of the air mix door 34 (a control signal output to the electric actuator for the air mix door 34), the air mix door 34 fully closes the cold air bypass passage 35 and blows air after passing through the indoor evaporator 17. The total air flow is determined to pass through the indoor condenser 12.

  Therefore, in the refrigeration cycle apparatus 10 in the heating mode, the refrigerant discharged from the compressor 11 flows into the indoor condenser 12. The refrigerant flowing into the indoor condenser 12 exchanges heat with the blown air that has passed through the indoor evaporator 17 to dissipate heat. Thereby, blowing air is heated.

  The refrigerant that has flowed out of the indoor condenser 12 flows into the first expansion valve 13 and is depressurized. The refrigerant decompressed by the first expansion valve 13 flows into the outdoor heat exchanger 14. The low-pressure refrigerant flowing into the outdoor heat exchanger 14 absorbs heat from the outside air blown from the blower fan and evaporates. The refrigerant that has flowed out of the outdoor heat exchanger 14 flows into the accumulator 21 through the heating bypass passage 19 because the heating on-off valve 20 is open and the second expansion valve 16 is fully closed. The subsequent operation is the same as in the cooling mode.

  Therefore, in the vehicle air conditioner 1 in the heating mode, the vehicle interior can be heated by blowing the blown air heated by the indoor condenser 12 into the vehicle interior.

(C) Dehumidification heating mode In the dehumidification heating mode, the air-conditioning control device 40 sets the first expansion valve 13 to the throttle state, opens the second expansion valve 16 to the full or throttle state, and closes the heating on-off valve 20. Thereby, in the dehumidification heating mode, as shown by the solid line arrow in FIG. 3, the compressor 11 → the indoor condenser 12 → the first expansion valve 13 → the outdoor heat exchanger 14 → the second expansion valve 16 → the indoor evaporator 17 → A refrigeration cycle in which the refrigerant is circulated in the order of the accumulator 21 → the suction port of the compressor 11 is configured. That is, a refrigeration cycle in which the refrigerant is circulated in substantially the same order as in the cooling mode is configured.

  Further, the air-conditioning control device 40 determines the operating states of the various control target devices (control signals to be output to the various control target devices) based on the target blowing temperature TAO, the detection signal of the sensor group, and the like with the configuration of the refrigerant circuit. To do.

  For example, the refrigerant discharge capacity of the compressor 11 (control signal output to the electric motor of the compressor 11) is determined so that the evaporator inlet side temperature Tein approaches the target evaporator outlet temperature TEO, as in the cooling mode. Is done. As for the throttle opening of the first expansion valve 13 (control signal output to the first expansion valve 13), the degree of supercooling of the refrigerant flowing into the first expansion valve 13 is the target supercooling, as in the heating mode. Determined to approach the degree.

  Further, the throttle opening degree of the second expansion valve 16 (control signal output to the second expansion valve 16) is determined as follows. First, the target condensation temperature TCO in the indoor condenser 12 is determined based on the target outlet temperature TAO with reference to a control map stored in the air conditioning control device 40 in advance. More specifically, in this control map, the target condensing temperature TCO is determined to increase as the target blowing temperature TAO increases.

  Further, the condenser average temperature Tca is calculated as in the heating mode. Then, based on the deviation between the target condensation temperature TCO and the condenser average temperature Tca, the feedback control method is used to output the condenser average temperature Tca to the second expansion valve 16 so as to approach the target condensation temperature TCO. A control signal is determined.

Therefore, in this embodiment, in accordance with the increase of the target condensing temperature TCO, increases the throttle opening degree of the second expansion valve 1 6 lowers the refrigerant evaporation temperature in the outdoor heat exchanger 14, the target condensation temperature TCO reducing the throttle opening degree of the second expansion valve 1 6 with the decrease results in increasing the refrigerant evaporation temperature in the outdoor heat exchanger 14.

  As for the opening degree of the air mix door 34 (control signal output to the electric actuator for the air mix door 34), the air mix door 34 fully closes the cold air bypass passage 35 as in the heating mode. It is determined.

Therefore, in the refrigeration cycle apparatus 10 in the dehumidifying and heating mode, the state of the refrigerant changes as shown in the Mollier diagram of FIG. In the Mollier diagram of FIG. 5, the target condensation temperature TCO has become relatively high, the second expansion valve 1 6 is shows a state in which a throttle opening degree close to the fully open.

  That is, in the refrigeration cycle apparatus 10 in the dehumidifying heating mode, the refrigerant discharged from the compressor 11 (point a5 in FIG. 5) flows into the indoor condenser 12 and is cooled and dehumidified by the indoor evaporator 17. Heat is exchanged with the blown air to dissipate heat (point a5 → b5 in FIG. 5). Thereby, blowing air is heated.

  The refrigerant flowing out of the indoor condenser 12 flows into the first expansion valve 13 and is depressurized (b5 point → c5 point in FIG. 5). The refrigerant decompressed by the first expansion valve 13 flows into the outdoor heat exchanger 14. The low-pressure refrigerant that has flowed into the outdoor heat exchanger 14 absorbs heat from the outside air blown from the blower fan and evaporates (point c5 → point d5 in FIG. 5).

  Since the heating on-off valve 20 is closed, the refrigerant flowing out of the outdoor heat exchanger 14 flows into the second expansion valve 16 and is depressurized (point d5 → point e5 in FIG. 5). The refrigerant decompressed by the second expansion valve 16 flows into the indoor evaporator 17. The refrigerant flowing into the indoor evaporator 17 absorbs heat from the blown air blown from the blower 32 and evaporates (point e5 → point f5 in FIG. 5). Thereby, blowing air is cooled. The subsequent operation is the same as in the cooling mode.

  Therefore, in the vehicle air conditioner 1 in the dehumidifying and heating mode, the dehumidifying and heating in the vehicle interior is performed by reheating the blown air cooled by the indoor evaporator 17 and dehumidified by the indoor condenser 12 and blowing it out into the vehicle interior. It can be performed.

Further, in the refrigeration cycle apparatus 10 of the present embodiment, when the dehumidifying and heating mode, the cycle configuration the outdoor heat exchanger 14 and the indoor evaporator 17 is series connected with respect to the refrigerant flow. Therefore, dehumidifying heating of the air-conditioning target space (vehicle interior) can be realized with a simpler cycle configuration than the cycle configuration in which the outdoor heat exchanger 14 and the indoor evaporator 17 are connected in parallel to the refrigerant flow. .

Here, the heating capacity Qc of the blown air in the indoor condenser 12 in the dehumidifying and heating mode (that is, the heat radiation amount of the refrigerant in the indoor condenser 12) will be described. The heating capacity Qc of the blown air in the indoor condenser 12 can be defined by the following formula F3.
Qc = Qe + L + Qo (F3)
In addition, Qe in Formula F2 is the dehumidifying ability of the blown air in the indoor evaporator 17 (that is, the heat absorption amount of the refrigerant in the indoor condenser 12), L is the compression work amount of the compressor 11, and Qo is This is the amount of heat absorbed by the refrigerant in the outdoor heat exchanger 14.

  Therefore, in the configuration in which the refrigerant discharge capacity of the compressor 11 is adjusted to obtain the desired dehumidification capacity Qe as in the dehumidification heating mode of the present embodiment, the heat absorption amount Qo is increased in order to increase the heating capacity Qc. It is necessary to let Furthermore, the heat absorption amount Qo increases as the temperature difference between the refrigerant evaporation temperature and the outside air temperature in the outdoor heat exchanger 14 increases.

  However, if the evaporator inlet side temperature Tein is controlled to be equal to or higher than the reference frost suppression temperature KTf in order to suppress the frost formation of the indoor evaporator 17, the refrigerant evaporation temperature in the outdoor heat exchanger 14 is also suppressed to the reference frost formation. The temperature tends to be higher than the temperature KTf.

  For this reason, when the outside air temperature is low (for example, when the outside air temperature is 10 ° C. or less), the temperature difference between the refrigerant evaporation temperature and the outside air temperature in the outdoor heat exchanger 14 is reduced, and the outdoor heat exchanger 14 The amount of heat absorbed by the refrigerant from the outside air tends to decrease. As a result, the heating capacity Qc of the blown air in the indoor condenser 12 may be insufficient.

  On the other hand, in the refrigeration cycle apparatus 10 of the present embodiment, a non-azeotropic refrigerant mixture whose saturation temperature rises as the dryness increases is employed as the refrigerant. As shown in FIG. The isotherm on the diagram is tilted. Thereby, the refrigerant | coolant evaporation temperature in the outdoor heat exchanger 14 connected to a refrigerant | coolant flow upstream can be made lower than the refrigerant | coolant evaporation temperature in the indoor evaporator 17 connected to a refrigerant | coolant flow downstream.

  Therefore, even when the outside air temperature is low, the reduction in the temperature difference between the outside air temperature and the refrigerant evaporation temperature in the outdoor heat exchanger 14 is suppressed, and the heat absorption amount Qo that the refrigerant absorbs heat from the outside air in the outdoor heat exchanger 14 is reduced. It can suppress that it reduces. As a result, it is possible to suppress a decrease in the heat dissipation amount of the refrigerant in the indoor condenser 12.

  That is, according to the refrigeration cycle apparatus 10 of the present embodiment, it is possible to suppress a decrease in the blowing air heating capacity Qc without complicating the cycle configuration in the dehumidifying heating mode.

  Further, in the refrigeration cycle apparatus 10 of the present embodiment, the second expansion valve 16 configured by a variable throttle mechanism is employed as the low-stage decompression means, so that the throttle opening of the second expansion valve 16 is in the dehumidifying heating mode. Can be changed. Thereby, the refrigerant | coolant evaporation temperature in the outdoor heat exchanger 14 can be changed, and the heating capability Qc of the blowing air in the indoor condenser 12 can be adjusted.

  Further, in the refrigeration cycle apparatus 10 of the present embodiment, the refrigerant discharge capacity of the compressor 11 is controlled so that the evaporator inlet side temperature Tein is equal to or higher than the reference frosting suppression temperature KTf in the cooling mode and the dehumidifying heating mode. Yes. Therefore, even if a non-azeotropic refrigerant mixture whose saturation temperature increases with an increase in dryness is employed, frost formation in the indoor evaporator 17 can be reliably suppressed.

  Further, in the refrigeration cycle apparatus 10 of the present embodiment, the condenser average temperature Tca is controlled so as to approach the target condensation temperature TCO during the heating mode and the dehumidifying heating mode. According to this, even if a temperature difference occurs between the condenser inlet side temperature Tcin and the condenser outlet side temperature Tcout by adopting the non-azeotropic refrigerant mixture, the blown air heated by the indoor condenser 12 The blast air temperature TAV is easily brought close to the user's desired temperature.

(Second Embodiment)
This embodiment demonstrates the example which changed the component apparatus of the refrigerating-cycle apparatus 10 as shown in FIGS. 6-8 with respect to 1st Embodiment. 6 to 8 correspond to FIGS. 1 to 3 of the first embodiment, and the same or equivalent parts as those of the first embodiment are denoted by the same reference numerals. The same applies to the following drawings.

  First, the refrigerant outlet of the indoor condenser 12 of this embodiment is connected to the inlet side of a high stage fixed throttle 13a as a high stage decompression means. An orifice, a capillary tube, or the like can be adopted as such a high stage side fixed throttle 13a.

  Furthermore, in this embodiment, the high stage side bypass passage 13b which guides the refrigerant | coolant which flowed out from the indoor condenser 12 to the refrigerant | coolant inlet side of the outdoor heat exchanger 14 by detouring the high stage side fixed throttle 13a is provided. The high stage side bypass passage 13b is provided with a high stage side opening / closing valve 13c which is a high stage side opening / closing means for opening and closing the high stage side bypass passage 13b. The basic configuration of the high stage side opening / closing valve 13c is the same as that of the heating opening / closing valve 20.

  Here, when the high stage side on-off valve 13c is open, the pressure loss that occurs when the refrigerant passes through the high stage side bypass passage 13b is the pressure loss that occurs when the refrigerant passes through the high stage side fixed throttle 13a. Is extremely small. Therefore, when the high stage side opening / closing valve 13c opens the high stage side bypass passage 13b, almost the entire flow rate of the refrigerant flowing out of the indoor condenser 12 is passed through the high stage side bypass passage 13b. 14 flows to the refrigerant inlet side.

  Moreover, the refrigerant | coolant inflow port of the electric three-way valve 15a is connected to the refrigerant | coolant outlet side of the outdoor heat exchanger 14 of this embodiment. The electric three-way valve 15a is connected to the refrigerant outlet side of the outdoor heat exchanger 14 and the other refrigerant inlet of the second three-way joint 18, and is fixed to the refrigerant outlet side and the lower stage side of the outdoor heat exchanger 14. It is a refrigerant circuit switching means for switching the refrigerant circuit that communicates with the inlet side of the throttle 16a. The operation of the electric three-way valve 15 a is controlled by a control voltage output from the air conditioning control device 40.

  One refrigerant outlet of the electric three-way valve 15a is connected to an inlet side of a low stage side fixed throttle 16a as a low stage side pressure reducing means. The basic configuration of the low stage side fixed aperture 16a is the same as that of the high stage side fixed aperture 13a.

  Further, in the present embodiment, a low-stage bypass passage 16b that guides the refrigerant flowing out from the electric three-way valve 15a to the refrigerant inlet side of the indoor evaporator 17 by bypassing the low-stage fixed throttle 16a is provided. A low-stage opening / closing valve 16c, which is a low-stage opening / closing means for opening / closing the low-stage bypass passage 16b, is disposed in the low-stage bypass passage 16b.

  The basic configurations of the low stage side bypass passage 16b and the low stage side opening / closing valve 16c are the same as those of the high stage side bypass passage 13b and the high stage side opening / closing valve 13c, respectively. Other configurations of the refrigeration cycle apparatus 10 and the vehicle air conditioner 1 are the same as those in the first embodiment.

  Next, the operation of the vehicle air conditioner 1 of the present embodiment having the above configuration will be described. Also in the vehicle air conditioner 1 of the present embodiment, the operation in the cooling mode, the heating mode, and the dehumidifying heating mode is switched just as in the first embodiment. Below, the operation | movement in each operation mode is demonstrated.

(A) Cooling mode In the cooling mode, the air conditioning control device 40 opens the high-stage side on-off valve 13c, closes the low-stage side on-off valve 16c, and further, the refrigerant outlet side and the low-stage side fixed throttle of the outdoor heat exchanger 14 The operation of the electric three-way valve 15a is controlled so as to communicate with the inlet side of 16a.

  Thereby, in the cooling mode, as shown by the solid line arrow in FIG. 6, the compressor 11 → the indoor condenser 12 → the high stage side bypass passage 13 b → the outdoor heat exchanger 14 → the low stage side fixed throttle 16 a → the indoor evaporator 17. A refrigeration cycle in which the refrigerant is circulated in the order of the accumulator 21 → the suction port of the compressor 11 is configured. The operations of the other components are the same as in the cooling mode of the first embodiment.

  Therefore, also in the cooling mode of the present embodiment, the vehicle interior can be cooled by blowing the blown air cooled by the indoor evaporator 17 into the vehicle interior, as in the cooling mode of the first embodiment. .

(B) Heating Mode In the heating mode, the air conditioning control device 40 closes the high stage side opening / closing valve 13c, and further communicates the refrigerant outlet side of the outdoor heat exchanger 14 and the other refrigerant inlet of the second three-way joint 18. Thus, the operation of the electric three-way valve 15a is controlled.

  As a result, in the heating mode, as indicated by the solid line arrow in FIG. 7, the compressor 11 → the indoor condenser 12 → the high-stage fixed throttle 13a → the outdoor heat exchanger 14 → the heating bypass passage 19 → the accumulator 21 → the compressor A refrigeration cycle in which the refrigerant is circulated in the order of 11 intake ports is configured. The operations of the other components are the same as in the heating mode of the first embodiment.

  Therefore, also in the heating mode of the present embodiment, similarly to the heating mode of the first embodiment, the vehicle interior can be heated by blowing the blown air heated by the indoor condenser 12 into the vehicle interior. .

(C) Dehumidification heating mode In the dehumidification heating mode, the air-conditioning control device 40 closes the high stage side opening / closing valve 13c, and further communicates the refrigerant outlet side of the outdoor heat exchanger 14 with the inlet side of the low stage side fixed throttle 16a. Thus, the operation of the electric three-way valve 15a is controlled.

  Thus, in the dehumidifying heating mode, as indicated by the solid line arrow in FIG. 8, the compressor 11 → the indoor condenser 12 → the high stage fixed throttle 13a → the outdoor heat exchanger 14 → the low stage fixed throttle 16a or the low stage side. A refrigeration cycle in which the refrigerant is circulated in the order of the bypass passage 16b → the indoor evaporator 17 → the accumulator 21 → the suction port of the compressor 11 is configured.

  Further, the air-conditioning control device 40 determines the operating states of the various control target devices (control signals to be output to the various control target devices) based on the target blowing temperature TAO, the detection signal of the sensor group, and the like with the configuration of the refrigerant circuit. To do.

  For example, the open / close state of the low-stage side opening / closing valve 16c is determined so that the condenser average temperature Tca approaches the target condensation temperature TCO, as in the first embodiment. More specifically, when the heating capacity Qc of the blown air in the indoor condenser 12 is increased, the low-stage side opening / closing valve 16c is opened to allow the refrigerant to flow into the low-stage side bypass passage 16b side. On the other hand, when decreasing the heating capacity Qc, the low-stage side on-off valve 16c is closed, and the refrigerant flows into the low-stage side fixed throttle 16a side. The operations of the other components are the same as in the cooling mode of the first embodiment.

  Therefore, also in the dehumidifying and heating mode of the present embodiment, similarly to the dehumidifying and heating mode of the first embodiment, the blast air cooled and dehumidified by the indoor evaporator 17 is reheated by the indoor condenser 12 and the vehicle is By blowing out into the room, dehumidifying heating in the passenger compartment can be performed. Furthermore, also in the refrigeration cycle apparatus 10 of the present embodiment, similarly to the first embodiment, it is possible to suppress a decrease in the blowing air heating capability Qc without complicating the cycle configuration.

  Further, since the refrigeration cycle apparatus 10 of the present embodiment includes the low-stage side on-off valve 16c, a refrigerant circuit that depressurizes the refrigerant with the low-stage side fixed throttle 16a and the refrigerant bypasses the low-stage side fixed throttle 16a. Thus, the refrigerant circuit that leads to the indoor evaporator 17 side can be switched. Thereby, the refrigerant | coolant evaporation temperature in the outdoor heat exchanger 14 can be changed, and the heating capability Qc of the blowing air in the indoor condenser 12 can be adjusted.

  Furthermore, the low stage side opening / closing valve 16c is intermittently opened / closed to adjust the valve opening rate (the time ratio at which the low stage side opening / closing valve 16c is open per unit time). The refrigerant evaporation temperature may be adjusted.

(Third embodiment)
In the present embodiment, an example in which the heating means is changed as shown in FIG. 9 with respect to the first embodiment will be described. A heating device 70 as heating means of the present embodiment includes a heat medium circulation circuit 71 that circulates a heat medium, a water pump 72 arranged in the heat medium circulation circuit 71, a heat medium-refrigerant heat exchanger 73, and a heater core. 74.

  The heat medium-refrigerant heat exchanger 73 heats the heat medium by exchanging heat between the refrigerant discharged from the compressor 11 and the heat medium. The heater core 74 is disposed in the casing 31 similarly to the indoor condenser 12 described in the first embodiment, and heats the blown air using the heat medium heated by the heat medium-refrigerant heat exchanger 73 as a heat source. Is.

  The water pump 72 is an electric pump that pumps the heat medium flowing out from the heater core 74 to the heat medium-refrigerant heat exchanger 73 side. In the present embodiment, when the water pump 72 is operated, the heat medium circulates in the order of the water pump 72 → the heat medium-refrigerant heat exchanger 73 → the heater core 74 → the water pump 72. The operation of the water pump 72 is controlled by a control voltage output from the air conditioning controller 40.

  Therefore, in the heating device 70 of the present embodiment, the refrigerant discharged from the compressor 11 can be radiated, and the blown air can be heated by the radiated heat. Other configurations of the refrigeration cycle apparatus 10 and the vehicle air conditioner 1 are the same as those in the first embodiment.

  Next, the operation of the vehicle air conditioner 1 of the present embodiment having the above configuration will be described. In the present embodiment, during the heating mode and the dehumidifying heating mode, the water pump 72 is operated so that the air conditioning control device 40 exhibits a predetermined water pressure feeding capability. Thereby, at the time of heating mode and dehumidification heating mode, the heat medium heated with the heat medium-refrigerant heat exchanger 73 can be flowed into the heater core 74, and blowing air can be heated.

  Other operations are the same as those in the first embodiment. Therefore, also in the vehicle air conditioner 1 of the present embodiment, it is possible to perform cooling, heating, and dehumidifying heating in the passenger compartment, as in the first embodiment. Furthermore, also in the refrigeration cycle apparatus 10 according to the present embodiment, it is possible to suppress a reduction in the heating capacity Qc of the blown air without complicating the cycle configuration in the dehumidifying heating mode.

  In the present embodiment, the example in which the heating unit is changed with respect to the first embodiment has been described. However, the cooling unit may be similarly changed. That is, as a cooling means, instead of the indoor evaporator 17, a cooling heat medium circulation circuit that circulates the heat medium, a cooling water pump disposed in the cooling heat medium circulation circuit, and cooling heat A cooling device having a medium-refrigerant heat exchanger and a cooler core may be employed.

  More specifically, the cooling heat medium-refrigerant heat exchanger only needs to cool the heat medium by evaporating the refrigerant flowing out of the second expansion valve 16 and exhibiting an endothermic action. The cooler core is disposed in the casing 31 in the same manner as the indoor evaporator 17 described in the first embodiment, and cools the blown air using the heat medium cooled by the cooling heat medium-refrigerant heat exchanger as a cooling heat source. Anything to do.

  And the effect similar to 1st Embodiment is acquired by operating the water pump for cooling so that the air-conditioning control apparatus 40 may exhibit the predetermined water pumping capability at least at the time of air_conditioning | cooling mode and dehumidification heating mode. Can do.

(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, the example in which the refrigeration cycle apparatus 10 of the present invention is applied to the vehicle air conditioner 1 mounted on an electric vehicle has been described, but the application of the present invention is not limited to this. For example, the driving force for driving the vehicle may be applied to a vehicle air conditioner mounted on a normal vehicle that obtains from the internal combustion engine (engine), or the driving force for driving from both the driving electric motor and the internal combustion engine. You may apply to the vehicle air conditioner mounted in the hybrid vehicle which obtains.

  Moreover, when applying to the vehicle which has an internal combustion engine, you may provide the auxiliary | assistant heating means which heats blowing air by using the cooling water of an internal combustion engine as a heat source as auxiliary | assistant heating means of blowing air. Furthermore, the refrigeration cycle apparatus 10 of the present invention is not limited to a vehicle, and may be applied to a stationary air conditioner or the like.

  (2) In the above-described embodiment, the example in which the evaporator inlet side temperature Tein is controlled to be equal to or higher than the reference frost suppression temperature KTf has been described. The evaporator outlet side temperature Teout may be controlled to be equal to or higher than a predetermined reference temperature, or the average value of the evaporator inlet side temperature Tein and the evaporator outlet side temperature Teout may be equal to or higher than a predetermined reference temperature. You may control to.

  (3) In the above-described embodiment, the example in which each operation mode is switched by executing the air conditioning control program has been described. However, the switching of each operation mode is not limited to this. For example, an operation mode setting switch for setting each operation mode may be provided on the operation panel, and the operation mode may be switched according to an operation signal of the operation mode setting switch.

  (4) The means disclosed in each embodiment described above may be combined as appropriate within a feasible range. For example, in the refrigeration cycle apparatus 10 described in the first embodiment, the electric three-way valve 15a described in the second embodiment may be employed instead of the first three-way joint 15.

  Further, in the refrigeration cycle apparatus 10 described in the first embodiment, the first stage expansion valve 13 is not changed, and instead of the second expansion valve 16, the low-stage fixed throttle 16a described in the second embodiment is reduced. A stage-side bypass passage 16b and a low-stage side opening / closing valve 16c may be employed. Moreover, you may apply the heating apparatus 70 demonstrated in 3rd Embodiment to the refrigerating-cycle apparatus 10 of 2nd Embodiment.

  (5) In the above-described embodiment, the refrigeration cycle apparatus 10 configured to be able to switch the operation mode has been described. However, at least if the operation in the dehumidifying heating mode can be performed, the effect of the present invention can be obtained. .

  (6) In the above-described embodiment, a refrigerant mainly composed of R1234yf and R32 is adopted as the refrigerant. However, the refrigerant is not limited to this, and the saturation temperature increases as the dryness increases. Any non-azeotropic refrigerant mixture can be used.

11 Compressor 12, 70 Indoor condenser, heating device (heating means)
13, 13a First expansion valve, high stage fixed throttle (high stage decompression means)
14 Outdoor heat exchanger 16, 16a Second expansion valve, low stage fixed throttle (low stage decompression means)
17 Indoor evaporator (cooling means)

Claims (5)

A refrigeration cycle apparatus applied to an air conditioner,
A compressor (11) for compressing and discharging the refrigerant;
Heating means (12, 70) for dissipating the refrigerant discharged from the compressor (11) and heating the air blown into the air-conditioning target space;
High-stage decompression means (13, 13a) for decompressing the refrigerant flowing out of the heating means (12, 70);
An outdoor heat exchanger (14) for exchanging heat between the refrigerant decompressed by the high-stage decompression means (13, 13a) and the outside air;
Cooling means (17) for evaporating the refrigerant flowing out of the outdoor heat exchanger (14) and cooling the blown air,
The heating means (12, 70) heats the blown air cooled by the cooling means (17) in a dehumidifying heating mode for performing dehumidifying heating of the air-conditioning target space,
The outdoor heat exchanger (14) evaporates the refrigerant during the dehumidifying heating mode,
As the refrigerant, a non-azeotropic refrigerant mixture whose saturation temperature increases with an increase in dryness is employed. Furthermore, a low-stage depressurization means (16) for depressurizing the refrigerant flowing out of the outdoor heat exchanger (14) and causing it to flow out to the cooling means (17) side,
The refrigeration cycle apparatus according to claim 1, wherein the low-stage depressurization means (16) includes a variable throttle mechanism configured to be capable of changing a throttle opening. Furthermore, a low-stage depressurization means (16a) for depressurizing the refrigerant flowing out of the outdoor heat exchanger (14) and causing the refrigerant to flow out to the cooling means (17) side,
A low-stage bypass passage (16b) for guiding the low-pressure refrigerant to the cooling means (17) side by bypassing the low-stage decompression means (16a);
The refrigeration cycle apparatus according to claim 1, further comprising low-stage side opening / closing means (16c) for opening and closing the low-stage side bypass passage (16b).   The temperature (Tein) of the refrigerant flowing into the cooling means (17) is adjusted so as to be equal to or higher than a predetermined reference temperature (KTf). Refrigeration cycle equipment.   The refrigeration cycle apparatus according to any one of claims 1 to 4, wherein the non-azeotropic refrigerant mixture is a mixture of at least R1234yf and R32.

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