JPWO2018229864A1 - Air conditioner - Google Patents

Abstract

A main circuit in which a compressor, a condenser, a throttle device, an evaporator, and an accumulator are sequentially connected, and a non-azeotropic mixed refrigerant including a first refrigerant and a second refrigerant having a higher boiling point than the first refrigerant circulates; A control device for controlling a circuit. The main circuit has a first regulating valve provided on the upstream side of the accumulator, a second regulating valve provided on the downstream side of the accumulator, and a bypass pipe for bypassing the accumulator. The control device controls the ratio of the first refrigerant in the non-azeotropic refrigerant mixture to be sucked into the compressor by controlling the first adjustment valve and the second adjustment valve, respectively.

Description

  The present invention relates to an air conditioner using a non-azeotropic mixed refrigerant.

  BACKGROUND ART Conventionally, an air conditioner having a refrigerant circuit in which a compressor, a condenser, an expansion valve, an evaporator, and an accumulator are sequentially connected by piping has been known (for example, see Patent Document 1). When performing the dehumidifying operation, the air conditioner of Patent Literature 1 raises the temperature of the air cooled by the evaporator by the condenser acting as a reheater, and suppresses the temperature decrease of the air blown into the room. I have.

  By the way, the refrigerant circulating through the refrigerant circuit includes a single refrigerant and a mixed refrigerant, and the mixed refrigerant includes an azeotropic mixed refrigerant obtained by mixing refrigerants having the same boiling point and a non-azeotropic mixed refrigerant obtained by mixing refrigerants having different boiling points. There is an azeotropic mixed refrigerant. The non-azeotropic refrigerant mixture includes a low-boiling refrigerant having a relatively low boiling point and a high-boiling refrigerant having a relatively high boiling point.

JP 2007-78242 A

  However, when a non-azeotropic mixed refrigerant is simply applied to a conventional air-conditioning apparatus as in Patent Document 1, a low-boiling refrigerant and a high-boiling refrigerant are mixed in the non-azeotropic mixed refrigerant. The discharge temperature is less likely to increase as compared with the case where a single refrigerant is used. That is, the conventional air conditioner has a problem in that it is not possible to perform efficient operation utilizing characteristics of the non-azeotropic mixed refrigerant.

  The present invention has been made to solve the above-described problem, and has as its object to provide an air conditioner that realizes efficient operation utilizing characteristics of a non-azeotropic mixed refrigerant.

  The air conditioner according to the present invention includes a compressor, a condenser, a throttle device, an evaporator, and an accumulator, which are sequentially connected, and includes a non-azeotropic mixture including a first refrigerant and a second refrigerant having a higher boiling point than the first refrigerant. A main circuit in which the refrigerant circulates, and a control device for controlling the main circuit, wherein the main circuit has a first regulating valve provided on the upstream side of the accumulator, and a second regulating valve provided on the downstream side of the accumulator. A valve connecting the valve between the evaporator and the first regulating valve, and between the second regulating valve and the compressor, and bypassing the accumulator; By controlling the first control valve and the second control valve, the ratio of the first refrigerant in the non-azeotropic refrigerant mixture to be sucked into the compressor is adjusted.

  According to the air conditioner of the present invention, by controlling the first adjustment valve and the second adjustment valve, respectively, the ratio of the first refrigerant in the non-azeotropic mixed refrigerant to be sucked into the compressor is adjusted. Since the pressure can be increased and the high pressure and the temperature of the refrigerant discharged from the compressor can be increased, an efficient operation utilizing the characteristics of the non-azeotropic mixed refrigerant can be realized.

FIG. 2 is a diagram showing a configuration related to a refrigerant circuit of the air conditioning system according to Embodiment 1 of the present invention. FIG. 2 is a block diagram illustrating a control system of the air-conditioning apparatus of FIG. 1. 2 is a flowchart showing an operation mainly of a dehumidifying operation and a defrosting operation of the air-conditioning apparatus of FIG. 1. 2 is a flowchart illustrating an operation of the air-conditioning apparatus of FIG. 1 in a heating amount increasing mode. FIG. 9 is a diagram illustrating a configuration related to a refrigerant circuit of an air conditioning system according to Embodiment 2 of the present invention. FIG. 6 is a block diagram illustrating a control system of the air-conditioning apparatus of FIG. 5. It is a flowchart which shows operation | movement centering on the dehumidification operation | movement and the defrost operation | movement of the air conditioner of FIG. It is a flowchart which shows the operation | movement in the heating amount up mode of the air conditioner of FIG.

Embodiment 1 FIG.
FIG. 1 is a diagram showing a configuration related to a refrigerant circuit of the air conditioning system according to Embodiment 1 of the present invention. As shown in FIG. 1, the air conditioning system 100 includes an air conditioner 200 and a controller 300. In the first embodiment, the air conditioner 200 is a dehumidifier installed in a room such as a room. The air conditioner 200 may be an industrial dehumidifier or a dehumidifier installed in a general home.

  The air conditioner 200 includes a compressor 1, a condenser 2, a throttle device 3, an evaporator 4, an accumulator (ACC) 6, a hot gas solenoid valve 7, a first solenoid valve 8, and a second solenoid valve 9. I have. The first solenoid valve 8 is provided upstream of the accumulator 6, that is, between the evaporator 4 and the accumulator 6. The second solenoid valve 9 is provided downstream of the accumulator 6, that is, between the accumulator 6 and the compressor 1.

  In the air conditioner 200, the compressor 1, the condenser 2, the expansion device 3, the evaporator 4, the first solenoid valve 8, the accumulator 6, and the second solenoid valve 9 are sequentially connected by the main pipe 20, and the refrigerant circulates. It has a main circuit 10. The main pipe 20 includes a discharge pipe 21 disposed on the high pressure side, a liquid pipe 22 disposed on the high pressure side, a liquid pipe 23 disposed on the low pressure side, and a suction pipe disposed on the low pressure side. 24.

  The discharge pipe 21 is a pipe that connects the discharge side of the compressor 1 and the inflow side of the condenser 2. The high-pressure refrigerant discharged from the compressor 1 flows through the discharge pipe 21. The liquid pipe 22 is a pipe connecting the outflow side of the condenser 2 and the inflow side of the expansion device 3. The high-pressure liquid refrigerant flowing out of the condenser 2 flows through the liquid pipe 22. The liquid pipe 23 is a pipe connecting the outflow side of the expansion device 3 and the inflow side of the evaporator 4. The low-pressure two-phase refrigerant flowing out of the expansion device 3 flows through the liquid pipe 23. The suction pipe 24 connects the outlet side of the evaporator 4 and the suction side of the compressor 1. The low-pressure gas refrigerant collected from the evaporator 4 flows through the suction pipe 24.

  The suction pipe 24 connects between the evaporator 4 and the first electromagnetic valve 8 and between the second electromagnetic valve 9 and the compressor 1, and has a bypass pipe 24 a that bypasses the accumulator 6. More specifically, upstream branch means 24b is provided in the suction pipe 24 upstream of the first electromagnetic valve 8, that is, between the evaporator 4 and the first electromagnetic valve 8. A downstream branching means 24 c is provided in the suction pipe 24 downstream of the second solenoid valve 9, that is, between the second solenoid valve 9 and the compressor 1. That is, the upstream branching unit 24b and the downstream branching unit 24c are connected by the bypass pipe 24a.

  Further, the air conditioner 200 has a hot gas bypass circuit 15 that connects between the discharge side of the compressor 1 and the condenser 2 and between the condenser 2 and the expansion device 3. The hot gas bypass circuit 15 has a hot gas defrost pipe 25 and the hot gas solenoid valve 7. More specifically, a first branching unit 25a is provided in the middle of the discharge pipe 21, and a second branching unit 25b is provided in the middle of the liquid pipe 22. That is, the first branching means 25a and the second branching means 25b are connected by the hot gas defrost pipe 25, and the hot gas defrost pipe 25 is provided with the hot gas solenoid valve 7.

  The air-conditioning apparatus 200 according to Embodiment 1 uses the first refrigerant and the second refrigerant having a higher boiling point than the first refrigerant as the refrigerant circulating in the refrigerant circuit formed by the main circuit 10 and the hot gas bypass circuit 15. And a non-azeotropic mixed refrigerant containing the same. In the non-azeotropic mixed refrigerant, the first refrigerant is a low-boiling refrigerant having a relatively low boiling point, and the second refrigerant is a high-boiling refrigerant having a relatively high boiling point.

More specifically, the non-azeotropic refrigerant mixture is, for example, R407C or R448A. Non-azeotropic mixed refrigerant, the R32, and R125, and R134a, and R1234yf, a mixed refrigerant of CO _2, and the condition is the ratio of R32 XR32 (wt%) is "33 <XR32 <39", R125 And the condition that the ratio XR134a (wt%) of R134a is “11 <XR134a <17”, and the condition that the ratio XR1234yf (wt%) of R1234yf is “27 <XR125 <33”. and conditions of "11 <XR1234yf <17", a condition percentage _XCO 2 of CO ₂ (wt%) is "3 _<XCO 2 <9", the sum of the XR32 and XR125 and XR134a and XR1234yf and XCO ₂ The refrigerant may satisfy all of the conditions of 100.

  The compressor 1 compresses a refrigerant. The compressor 1 may be a constant speed compressor or an inverter compressor having a motor driven by an inverter. The condenser 2 condenses the refrigerant compressed in the compressor 1. The condenser 2 is composed of, for example, a fin-and-tube heat exchanger, and exchanges heat between the refrigerant and the air. The expansion device 3 includes, for example, an electronic expansion valve and expands the refrigerant condensed in the condenser 2. The evaporator 4 evaporates the refrigerant expanded in the expansion device 3. The evaporator 4 is formed of, for example, a fin-and-tube heat exchanger, and exchanges heat between the refrigerant and air.

  By the way, when the refrigerant that cannot be evaporated by the evaporator 4 is sucked into the compressor 1 in a liquid state, the compressor 1 causes liquid compression. That is, when the liquid refrigerant is sucked into the compressor 1, a large pressure is generated inside the compressor 1 because the liquid is incompressible, and a strong impact sound is generated. Further, when the liquid refrigerant dissolves in the oil in the compressor 1, the concentration of the oil is diluted and the viscosity of the oil is reduced, so that the compressor 1 may fail due to poor lubrication. In order to prevent such inconvenience, the main circuit 10 of the air conditioner 200 is provided with an accumulator 6. Whether the liquid refrigerant has returned to the compressor 1 can be determined based on the value of the suction superheat degree (hereinafter, referred to as suction SH). The suction SH can be obtained by subtracting the low pressure saturation temperature from the suction temperature measured by the suction pipe temperature sensor 33, which will be described in detail later.

  The accumulator 6 separates the refrigerant flowing into the container into a gas and a liquid, and returns the gas refrigerant to the compressor 1. The hot gas electromagnetic valve 7 is an electromagnetic valve that is in an open state for allowing the refrigerant to pass when in the ON state, and is in a closed state for shutting off the refrigerant when in the OFF state. If the hot gas solenoid valve 7 is in the ON state, the refrigerant discharged from the compressor 1 passes through the hot gas bypass circuit 15.

  Each of the first solenoid valve 8 and the second solenoid valve 9 is an open valve that allows the refrigerant to pass therethrough when it is in the ON state, and is a closed valve that shuts off the refrigerant when it is off. When the first solenoid valve 8 and the second solenoid valve 9 are ON, the refrigerant that has passed through the evaporator 4 passes through the accumulator 6. The first solenoid valve 8 corresponds to a “first regulating valve” of the present invention, and the second solenoid valve 9 corresponds to a “second regulating valve” of the present invention.

  Further, the air conditioner 200 has a fan 5 shared by the evaporator 4 and the condenser 2. The fan 5 can send air to the evaporator 4 and also send air to the condenser 2. That is, the fan 5 acts to promote the evaporation of the refrigerant in the evaporator 4, that is, the release of cold heat, and to promote the condensation of the refrigerant in the condenser 2, that is, the release of warm heat.

  Further, the air conditioner 200 includes a discharge pipe temperature sensor 31, a high pressure sensor 32, a suction pipe temperature sensor 33, and a low pressure sensor 34. The discharge pipe temperature sensor 31 is provided around the discharge port of the compressor 1 and measures a discharge temperature that is the temperature of the refrigerant discharged from the compressor 1. The high pressure sensor 32 is provided around a discharge port of the compressor 1 and measures a high pressure, which is a pressure of the refrigerant discharged from the compressor 1. The suction pipe temperature sensor 33 is provided around the suction port of the compressor 1 and measures the suction temperature which is the temperature of the refrigerant drawn into the compressor 1. The low pressure sensor 34 is provided around the suction port of the compressor 1 and measures a low pressure that is the pressure of the refrigerant sucked into the compressor 1.

  The air conditioner 200 includes a control device 50 that controls the main circuit 10, the hot gas bypass circuit 15, and the fan 5. That is, the control device 50 controls the operation of various actuators in the air-conditioning apparatus 200 such as the compressor 1, the throttle device 3, the hot gas solenoid valve 7, the first solenoid valve 8, the second solenoid valve 9, and the fan 5. And manage it. For example, the controller 50 adjusts the ratio of the first refrigerant in the non-azeotropic refrigerant mixture to be sucked into the compressor 1 by adjusting the open / close state of each of the first solenoid valve 8 and the second solenoid valve 9. It is. Hereinafter, the ratio of the first refrigerant in the non-azeotropic refrigerant mixture to be drawn into the compressor 1 is also simply referred to as “the ratio of the first refrigerant”.

(Basic refrigerant flow)
Next, the basic flow of the refrigerant in the refrigerant circuit of the air conditioner 200 will be described.
The high-temperature and high-pressure gas refrigerant discharged from the compressor 1 enters the condenser 2 through the discharge pipe 21. The gas refrigerant that has entered the condenser 2 exchanges heat with the air, thereby releasing heat and liquefying. The refrigerant liquefied in the condenser 2 flows into the expansion device 3 through the liquid pipe 22 and is decompressed in the expansion device 3 to be in a gas-liquid two-phase state. Then, the refrigerant in the gas-liquid two-phase state in the expansion device 3 flows into the evaporator 4 through the liquid pipe 23 and exchanges heat with air in the evaporator 4 to release cold heat. And gasify. Further, the refrigerant gasified by the evaporator 4 passes through the suction pipe 24, is sucked from the suction side of the compressor 1, and is compressed again. That is, in the air-conditioning apparatus 200, the refrigeration cycle is formed by repeating the above-described circulation process of the refrigerant in the refrigerant circuit.

  By the way, in the air-conditioning apparatus 200, as shown by the dashed-dotted white arrow in FIG. 1, the room air sucked from the room passes through the evaporator 4 and then passes through the condenser 2. . Therefore, the room air is cooled when passing through the evaporator 4 and is heated when passing through the condenser 2. That is, when the room air passes through the evaporator 4, it receives cold heat and becomes lower than the dew point. Therefore, part of the room air is condensed on the evaporator 4 and is cooled and dehumidified. On the other hand, the room air that has passed through the evaporator 4 receives heat and reaches a predetermined temperature when passing through the condenser 2, and is discharged indoors as air having a low relative humidity. That is, in the air conditioner 200, the condenser 2 acts as a reheater that reheats the cooled air when passing through the evaporator 4.

  FIG. 2 is a block diagram showing a control system of the air conditioner of FIG. The configuration of the control device 50 will be specifically described with reference to FIG. As shown in FIG. 2, the control device 50 includes a control unit 51, an operation unit 52, and a storage unit 53. The operation unit 52 receives an input operation regarding various settings such as a target temperature and a target pressure, and outputs a signal corresponding to the content of the input operation to the control unit 51. The storage unit 53 includes a RAM (Random Access Memory) for storing various data, and a ROM (Read Only Memory) for storing a program for the control unit 51 to perform control in each operation mode. Have been.

  The control unit 51 includes, for example, a CPU (Central Processing Unit), a microcomputer, or a DSP (Digital Signal Processor). The control unit 51 includes information on the discharge temperature measured by the discharge pipe temperature sensor 31, information on the high pressure measured by the high pressure sensor 32, information on the suction temperature measured by the suction pipe temperature sensor 33, and information on the low pressure sensor. The information of the low pressure measured by 34 is input.

  The control unit 51 causes the air-conditioning apparatus 200 to execute the dehumidifying operation, the operation in the heating amount increasing mode, and the defrosting operation. The control unit 51 controls operations of various actuators in the air conditioner 200 based on information output from various sensors, signals output from the operation unit 52, signals transmitted from the controller 300, and the like. It is.

  For example, the control unit 51 appropriately controls the open / close state of the first solenoid valve 8 and the second solenoid valve 9 according to a program in the ROM of the storage unit 53, and adjusts the composition of the refrigerant to be drawn into the compressor 1. is there. That is, the control unit 51 controls the opening and closing of the first solenoid valve 8 and the second solenoid valve 9 and adjusts the amount of the liquid refrigerant remaining in the accumulator 6, thereby changing the composition of the refrigerant in the refrigerant circuit, that is, the refrigerant circuit. This is to change the ratio of the circulating low-boiling refrigerant.

  The control unit 51 can increase the ratio of the first refrigerant by opening the first solenoid valve 8 and the second solenoid valve 9. When the ratio of the first refrigerant increases, the value of the low pressure measured by the low pressure sensor 34 increases, the amount of the refrigerant circulating in the refrigerant circuit increases, and the value of the high pressure measured by the high pressure sensor 32 increases. The value of the discharge temperature measured by the tube temperature sensor 31 increases. Therefore, since the temperature difference between the temperature of the evaporator 4 and the temperature of the refrigerant flowing into the evaporator 4 increases, the defrosting time in the defrosting operation can be reduced, and the dehumidifying efficiency can be increased. The dehumidification efficiency in the first embodiment is determined using a value obtained by dividing the dehumidification operation time by the defrost time (dehumidification operation time / defrost time) as an index.

  The controller 300 is connected to the control device 50 by wire or wirelessly, and communicates with the control unit 51. The controller 300 is provided with an ON switch for starting operation of the air conditioner 200, an OFF switch for stopping operation of the air conditioner 200, a heating amount adjustment switch for increasing a heating amount, and the like. I have. The controller 300 receives an input operation by a user and transmits a signal corresponding to the content of the input operation to the control unit 51.

(During dehumidification operation)
The controller 51 determines the open / close state of the first solenoid valve 8 and the second solenoid valve 9 by checking whether the suction SH is higher or lower than the first threshold during the dehumidifying operation. More specifically, the control unit 51 obtains the suction SH by subtracting the low pressure saturation temperature from the suction temperature input from the suction pipe temperature sensor 33. The low pressure saturation temperature is a value obtained by converting the value of the low pressure input from the low pressure sensor 34 into a saturation temperature. The storage unit 53 stores, for example, a conversion table, which is table information that associates the low-pressure pressure with the saturation temperature. The control unit 51 illuminates the low-pressure information input from the low-pressure sensor 34 with the conversion table. Thus, the low pressure saturation temperature is determined. Then, the control unit 51 determines whether or not the obtained suction SH is equal to or less than the first threshold, and if the suction SH is equal to or less than the first threshold, the control unit 51 opens the first solenoid valve 8 and the second solenoid valve 9. State.

  When the first solenoid valve 8 and the second solenoid valve 9 are opened, the ratio of the first refrigerant sucked into the compressor 1 increases, and the discharge temperature rises. The temperature difference with the temperature of the entering refrigerant increases. Therefore, when trying to obtain the same heat exchange amount in the condenser 2, if the compressor 1 is an inverter compressor whose frequency can be adjusted by an inverter, the compressor 1 is more effective than when the compressor 1 is a constant speed compressor. Since the operation frequency can be reduced, the operation efficiency can be improved. That is, according to the air conditioner 200 equipped with the inverter compressor as the compressor 1, it is possible to increase the COP (Coefficient of Performance: coefficient of performance).

  More specifically, when the first solenoid valve 8 and the second solenoid valve 9 are opened, the control unit 51 performs a COP up operation that lowers the frequency of the compressor 1, that is, the operating frequency of the motor of the compressor 1. It may be. For example, when the control unit 51 opens the first solenoid valve 8 and the second solenoid valve 9 or when the waiting time elapses after the first solenoid valve 8 and the second solenoid valve 9 are opened, the control unit 51 performs compression. The frequency of the machine 1 may be reduced. The waiting time may be set and changed via the operation unit 52 or the controller 300, or may be automatically set by the control unit 51 according to the operating state or the installation environment. However, the control unit 51 may increase the frequency of the compressor 1 when the first solenoid valve 8 and the second solenoid valve 9 are closed. The control unit 51 can perform such a COP increase operation and the like also during the defrost operation and the operation in the heating amount increase mode.

  Further, after opening the first solenoid valve 8 and the second solenoid valve 9, the control unit 51 calculates the suction SH over time and determines whether the calculated suction SH is equal to or more than a second threshold value. It is. The control unit 51 closes the first solenoid valve 8 and the second solenoid valve 9 when the suction SH reaches the second threshold.

  Here, the first threshold value is a temperature serving as a reference for timing of opening the first solenoid valve 8 and the second solenoid valve 9 during the dehumidifying operation, and is set to, for example, 5K. The second threshold value is a temperature serving as a reference for the timing of closing the first solenoid valve 8 and the second solenoid valve 9 that have been opened once during the dehumidifying operation. The second threshold is set to a temperature higher than the first threshold, for example, 15K. The first threshold and the second threshold can be appropriately changed according to the configuration of the air-conditioning apparatus 200, the installation environment, and the like. The user can set and change the first threshold value and the second threshold value by operating the operation unit 52 or the controller 300.

(During operation in the heating up mode)
The user can perform, via the operation unit 52 or the controller 300, a setting operation of the heating amount up mode for increasing the heating amount by the condenser 2. The heating-up mode is a mode in which the control unit 51 controls the opening and closing of the first solenoid valve 8 and the second solenoid valve 9 in accordance with a change in the discharge temperature measured by the discharge pipe temperature sensor 31, thereby increasing the heating capacity. This is an operation mode in which rapid dehumidification operation is performed by adjustment. Here, the rapid dehumidifying operation is an operation in which air having a low relative humidity is supplied into a room to provide an air environment having a desired humidity in a shorter time than a normal dehumidifying operation.

  In the setting operation of the heating amount up mode, in addition to the operation of instructing the start of the heating amount up mode, the operation of setting the time to start the heating amount up mode, or the time until starting the heating amount up mode is set. Operations are included. Further, the setting operation of the heating amount up mode includes an operation of setting the heating amount up continuation time, which is a time period during which the control unit 51 continues the control in the heating amount up mode. That is, the user can set and change the heating amount increase continuation time by operating the operation unit 52 or the controller 300.

  In the heating amount increasing mode, the control unit 51 first opens the first solenoid valve 8 and the second solenoid valve 9 while the compressor 1 is operating. More specifically, the control unit 51 detects the start of the heating amount increase mode in accordance with a signal from the operation unit 52 or the controller 300 or a setting content of the operation unit 52 or the controller 300. When detecting the start of the heating amount increasing mode in a state where the compressor 1 is operating, the control unit 51 opens the first solenoid valve 8 and the second solenoid valve 9. When detecting the start of the heating amount increasing mode, if the compressor 1 is stopped, the control unit 51 waits until the compressor 1 starts operating, and when the compressor 1 starts operating. , The first solenoid valve 8 and the second solenoid valve 9 are opened.

  When the first solenoid valve 8 and the second solenoid valve 9 are opened, the composition of the non-azeotropic mixed refrigerant in the refrigerant circuit changes, and the ratio of the first refrigerant circulating in the refrigerant circuit increases. That is, the control unit 51 can increase the ratio of the first refrigerant by opening the first solenoid valve 8 and the second solenoid valve 9. When the ratio of the first refrigerant circulating in the refrigerant circuit increases, the low pressure increases, the amount of refrigerant circulating in the refrigerant circuit increases, and the high pressure and the discharge temperature increase. The control unit 51 causes the first solenoid valve 8 and the second solenoid valve 9 to maintain the open state until the discharge temperature input from the discharge pipe temperature sensor 31 reaches a closed threshold set at, for example, 120 ° C.

  After opening the first solenoid valve 8 and the second solenoid valve 9, the controller 51 sets the first solenoid valve 8 and the second solenoid valve 9 when the discharge temperature input from the discharge pipe temperature sensor 31 rises to the close threshold. The second solenoid valve 9 is closed. Further, after closing the first solenoid valve 8 and the second solenoid valve 9, the control unit 51 lowers the discharge temperature input from the discharge pipe temperature sensor 31 to, for example, a set open threshold value of 110 ° C. Until the first solenoid valve 8 and the second solenoid valve 9 are closed. The control unit 51 opens the first solenoid valve 8 and the second solenoid valve 9 when the discharge temperature input from the discharge pipe temperature sensor 31 decreases to the open threshold.

  Here, the closing threshold value is a temperature that is a reference for the timing of closing the first solenoid valve 8 and the second solenoid valve 9 during the operation in the heating amount increasing mode. The closed threshold may be set to a temperature higher than the closed reference threshold. The open threshold value is a temperature that is a reference for the timing of reopening the first solenoid valve 8 and the second solenoid valve 9 once closed during the operation in the heating amount increasing mode, and is set to a temperature lower than the close threshold value. The open threshold may be set to a temperature lower than the close reference temperature and higher than the open reference temperature. The closed threshold and the open threshold can be appropriately changed according to the configuration of the air conditioner 200, the installation environment, and the like. By operating the operation unit 52 or the controller 300, the user can set and change the open threshold value and the close threshold value.

  In addition, the control unit 51 has a heating amount up timer (not shown) for measuring an elapsed time after opening the first solenoid valve 8 and the second solenoid valve 9. That is, when the first solenoid valve 8 and the second solenoid valve 9 are opened, the control unit 51 starts time counting by the heating amount up timer. Then, when the heating amount up timer counts up, that is, when the heating amount up time has elapsed since the first solenoid valve 8 and the second solenoid valve 9 were first opened, the control unit 51 starts heating. This ends the quantity increase mode and shifts to normal operation. In the first embodiment, the normal operation corresponds to a normal dehumidification operation.

(During defrosting operation: Hot gas defrosting)
The control unit 51 determines whether or not the air conditioner 200 is performing a defrosting operation based on the open / closed state of the hot gas solenoid valve 7. During the defrosting operation, the hot gas solenoid valve 7 is open. That is, the control unit 51 determines that the defrosting operation is being performed when the hot gas solenoid valve 7 is open, and determines that the defrosting operation is not being performed when the hot gas solenoid valve 7 is closed. The judgment is made. In the first embodiment, if the hot gas solenoid valve 7 is in the closed state, the control unit 51 determines that the dehumidifying operation is being performed.

  When determining that the air-conditioning apparatus 200 is in the defrosting operation, the control unit 51 opens the first solenoid valve 8 and the second solenoid valve 9 to open the non-azeotropic mixed refrigerant to be sucked into the compressor 1. By changing the composition, the ratio of the first refrigerant is increased. After opening the first solenoid valve 8 and the second solenoid valve 9, the control unit 51 sets the first electromagnetic valve when the discharge temperature input from the discharge pipe temperature sensor 31 reaches the closed reference threshold. The valve 8 and the second solenoid valve 9 are closed once to suppress an increase in the discharge temperature. Further, after closing the first solenoid valve 8 and the second solenoid valve 9, the controller 51 sets the first solenoid valve when the discharge temperature input from the discharge pipe temperature sensor 31 falls to the open reference threshold. The valve 8 and the second solenoid valve 9 are opened again.

  Here, the closing reference threshold value is a temperature serving as a reference for timing of closing the first solenoid valve 8 and the second solenoid valve 9 during the defrosting operation, and is set to, for example, 115 ° C. The opening reference threshold value is a temperature that is a reference for timing when the first solenoid valve 8 and the second solenoid valve 9 that have been closed are reopened during the defrosting operation. The open reference threshold is set to a temperature lower than the close reference threshold, for example, 105 ° C. The open reference threshold and the close reference threshold can be appropriately changed according to the configuration of the air conditioner 200, the installation environment, and the like. By operating the operation unit 52 or the controller 300, the user can set and change the open reference threshold and the close reference threshold.

  The control unit 51 has a function of determining whether or not the defrosting operation end condition has been satisfied. When the defrosting operation end condition is satisfied, the defrosting operation is ended. For example, the control unit 51 may be configured to start the defrosting operation by estimating that the evaporator 4 is in a frosted state when the dehumidifying operation is continuously performed for a predetermined set time. In the case of adopting such a configuration, for example, a temperature sensor such as a thermistor is provided at the air suction port of the air conditioner 200, and the control unit 51 determines the set time of the dehumidifying operation based on the temperature measured by the temperature sensor, You may make it determine the defrost time which is the time which continues a frost driving | operation. Then, the control unit 51 may start timing when the defrosting operation is started, and may end the defrosting operation when the defrosting time has elapsed. In this case, when the defrost time has elapsed, the defrost operation end condition is satisfied.

  Further, the control unit 51 may determine the start and end timings of the defrosting operation according to the temperature of the evaporator 4. In the case of adopting such a configuration, for example, an evaporator 4 may be provided with an evaporating temperature sensor including a thermistor or the like. Then, the control unit 51 starts the defrosting operation when the temperature measured by the evaporating temperature sensor has decreased to the start threshold, and thereafter, when the temperature measured by the evaporating temperature sensor has increased to the end threshold. The operation may be terminated. In this case, when the temperature measured by the evaporation temperature sensor rises to the termination threshold, the defrosting operation termination condition is satisfied. Note that the end threshold is set to a temperature higher than the start threshold.

(Method of Opening / Closing Control of First Adjustment Valve 11 and Second Adjustment Valve 12)
FIG. 3 is a flowchart illustrating an operation centering on the dehumidifying operation and the defrosting operation of the air-conditioning apparatus of FIG. 1. FIG. 4 is a flowchart illustrating an operation of the air-conditioning apparatus of FIG. 1 in a heating amount increasing mode. A method for controlling the opening and closing of the first solenoid valve 8 and the second solenoid valve 9 will be described with reference to FIGS. First, an operation control method centering on the dehumidifying operation and the defrosting operation of the air conditioner will be described with reference to FIG.

  The control unit 51 determines whether or not the compressor 1 is operating (step S101). If the compressor 1 is not operating, the control unit 51 waits until the compressor 1 starts operating (step S101 / NO). ). When detecting the start of the heating amount increasing mode (step S102 / YES) during operation of the compressor 1 (step S101 / YES), the control unit 51 shifts to the heating amount increasing mode (see FIG. 4). When the control unit 51 does not detect the start of the heating amount increasing mode during the operation of the compressor 1 (step S101 / YES) (step S102 / NO), whether the air-conditioning apparatus 200 is performing the defrosting operation. It is determined whether or not it is (step S103).

(Defrosting operation)
The control unit 51 detects that the hot gas electromagnetic valve 7 is open and determines that the air-conditioning apparatus 200 is performing the defrosting operation (step S103 / YES), and the first electromagnetic valve 8 and the second electromagnetic valve The ratio of the first refrigerant is increased by opening the second solenoid valve 9 (step S104).

  Next, the control unit 51 determines whether or not the discharge temperature input from the discharge pipe temperature sensor 31 is equal to or higher than the close reference threshold (Step S105). If the discharge temperature is less than the closing reference threshold (step S105 / NO), the control unit 51 determines whether or not the defrosting operation end condition is satisfied (step S106). If the defrosting operation end condition is satisfied (step S106 / YES), the control unit 51 returns to the process of step S102. If the defrosting operation end condition is not satisfied (step S106 / NO), the control unit 51 returns to the process of step S105.

  On the other hand, when the discharge temperature reaches the close reference threshold value (step S105 / YES), the control unit 51 closes the first solenoid valve 8 and the second solenoid valve 9 to suppress a rise in the discharge temperature (step S107). . Then, the control unit 51 determines whether or not the discharge temperature input from the discharge pipe temperature sensor 31 is equal to or lower than the open reference threshold (Step S108).

  If the discharge temperature is higher than the open reference threshold, the control unit 51 causes the first solenoid valve 8 and the second solenoid valve 9 to maintain the closed state (step S108 / NO). However, after closing the first solenoid valve 8 and the second solenoid valve 9 in step S107, the controller 51 sets the defrosting operation end condition until the discharge temperature falls to the open reference threshold (step S108 / NO). If so, the process returns to step S102.

  When the discharge temperature has dropped to the open reference threshold (step S108 / YES), the control unit 51 opens the first solenoid valve 8 and the second solenoid valve 9 (step S109). Next, the control unit 51 determines whether or not the defrosting operation end condition is satisfied (Step S110). If the defrosting operation end condition is satisfied (step S110 / YES), control unit 51 returns to the process of step S102. If the defrosting operation end condition is not satisfied (step S110 / NO), control unit 51 returns to step S105.

(Dehumidification operation)
The control unit 51 detects that the hot gas solenoid valve 7 is closed and determines that the air-conditioning apparatus 200 is in the dehumidifying operation (step S103 / NO), calculates the suction SH, and calculates the calculated suction. It is determined whether SH is equal to or less than a first threshold (step S201).

  When the suction SH is higher than the first threshold value (step S201 / NO), the control unit 51 determines that the first electromagnetic valve 8 and the second electromagnetic valve 9 do not perform liquid compression in the compressor 1. The process returns to step S102 while maintaining the closed state. On the other hand, if the suction SH is equal to or less than the first threshold (step S201 / YES), the control unit 51 opens the first solenoid valve 8 and the second solenoid valve 9 (step S202).

  Further, the control unit 51 obtains the inhalation SH over time, and determines whether or not the obtained inhalation SH is equal to or larger than the second threshold (step S203). The control unit 51 causes the first solenoid valve 8 and the second solenoid valve 9 to maintain the open state until the obtained suction SH reaches the second threshold value (step S203 / NO). Then, when the suction SH reaches the second threshold value (step S203 / YES), the control unit 51 closes the first solenoid valve 8 and the second solenoid valve 9 (step S204), and returns to the processing of step S102.

  Next, an operation control method in the heating amount increasing mode of the air conditioner will be described with reference to FIG. When detecting the start of the heating amount increasing mode in step S102 of FIG. 3 (step S102 / YES), the control unit 51 determines whether or not the compressor 1 is operating (step S301). Then, if the compressor 1 is not operating, the control unit 51 waits until the compressor 1 starts operating (step S301 / NO).

  When the compressor 1 is operating or when the compressor 1 starts operating (step S301 / YES), the control unit 51 opens the first solenoid valve 8 and the second solenoid valve 9 to control the refrigerant. And the ratio of the first refrigerant is increased. At that time, the control unit 51 starts time measurement by the heating amount up timer (step S302).

  Next, the control unit 51 determines whether or not the discharge temperature input from the discharge pipe temperature sensor 31 is equal to or higher than the close threshold (Step S303). If the discharge temperature is lower than the closing threshold, the control unit 51 causes the first solenoid valve 8 and the second solenoid valve 9 to maintain the open state (step S303 / NO). On the other hand, when the discharge temperature has risen to the open threshold (step S303 / YES), the control unit 51 determines whether or not the heating amount up timer has counted up (step S304).

  When the heating amount up timer counts up (step S304 / YES), the control unit 51 ends the heating amount up mode (step S305), and shifts to the normal operation. On the other hand, if the heating amount up timer does not count up (step S304 / NO), the control unit 51 closes the first solenoid valve 8 and the second solenoid valve 9 (step S306).

  Then, when the heating amount up timer counts up (step S307 / YES), the control unit 51 ends the heating amount up mode (step S308) and shifts to the normal operation. On the other hand, if the heating amount up timer does not count up (step S307 / NO), the control unit 51 determines whether the discharge temperature input from the discharge pipe temperature sensor 31 is equal to or less than the open threshold. A determination is made (step S309).

  If the discharge temperature is higher than the open threshold (step S309 / NO), the control unit 51 causes the first solenoid valve 8 and the second solenoid valve 9 to maintain the closed state, and returns to the processing of step S307. On the other hand, when the discharge temperature has dropped to the opening threshold (step S309 / YES), the control unit 51 opens the first solenoid valve 8 and the second solenoid valve 9 (step S310), and returns to the process of step S303.

  As described above, according to the air-conditioning apparatus 200, by controlling the first solenoid valve 8 and the second solenoid valve 9, respectively, the ratio of the first refrigerant in the non-azeotropic mixed refrigerant to be drawn into the compressor 1 is reduced. adjust. Therefore, since the low pressure can be increased, and the high pressure and the temperature of the refrigerant discharged from the compressor 1 can be increased, an efficient operation utilizing the characteristics of the non-azeotropic refrigerant mixture can be realized. it can.

  By the way, in the conventional air conditioner, when the non-azeotropic refrigerant mixture is applied, the discharge temperature is less likely to increase than when the single refrigerant having a low boiling point is applied. Therefore, the defrosting of the evaporator 4 during the defrosting operation is performed. There is a problem that the amount of heat to perform is insufficient, and it takes time to complete the defrosting. In this regard, the air conditioner 200 of Embodiment 1 opens the first solenoid valve 8 and the second solenoid valve 9 during the defrosting operation to increase the ratio of the first refrigerant that is a low-boiling refrigerant. Can be. Therefore, the temperature difference between the temperature of the evaporator 4 and the temperature of the refrigerant circulating in the refrigerant circuit and entering the evaporator 4 increases, so that the defrosting time can be reduced. And since the ratio of the defrosting time to the dehumidifying operation time can be reduced, the defrosting efficiency can be improved.

  In the heating amount increasing mode, the control unit 51 controls the opening and closing of the first solenoid valve 8 and the second solenoid valve 9 based on the discharge temperature measured by the discharge pipe temperature sensor 31. Thereby, the control unit 51 can adjust the heat exchange amount of the condenser 2 acting as the reheater, so that the rapid dehumidifying operation can be realized. In addition, when the air-conditioning apparatus 200 includes an inverter compressor as the compressor 1, the control unit 51 can perform the COP-up operation, so that the operation efficiency can be improved. In addition, when a DC fan is mounted as the fan 5 during the COP up operation, the COP can be further improved by adjusting the air volume.

  Further, after opening the first solenoid valve 8 and the second solenoid valve 9, when the discharge temperature, which is the temperature of the refrigerant discharged from the compressor, reaches the closed reference threshold, the control unit 51 performs the first electromagnetic control. Since the valve 8 and the second solenoid valve 9 are closed, an excessive rise in the discharge temperature can be suppressed. Moreover, since the first solenoid valve 8 and the second solenoid valve 9 are solenoid valves having an open state and a closed state, respectively, the air conditioner 200 can improve air conditioning control efficiency by simple control. Can be achieved.

  That is, the air conditioner 200 opens the first solenoid valve 8 and the second solenoid valve 9 at a predetermined timing and increases the ratio of the low boiling point refrigerant circulating in the refrigerant circuit, thereby increasing the low pressure and increasing the refrigerant circuit pressure. Increase the amount of refrigerant circulating in the chamber, and increase the discharge temperature and high pressure. For this reason, the defrosting time can be reduced, the defrosting efficiency can be increased, and the operating efficiency can be improved.

Embodiment 2 FIG.
FIG. 5 is a diagram showing a configuration related to a refrigerant circuit of an air conditioning system according to Embodiment 2 of the present invention. As shown in FIG. 5, the configuration of an air conditioning system 100A according to the second embodiment is the same as that of the air conditioning system 100 according to the first embodiment, but the configuration of the refrigerant circuit is different. That is, it is characterized in that the main circuit 10 of the air conditioner 200 </ b> A has the first regulating valve 11 and the second regulating valve 12 instead of the first solenoid valve 8 and the second solenoid valve 9. The same components as those in the first embodiment will be denoted by the same reference numerals, and description thereof will be omitted. Hereinafter, the configuration and operation particularly related to the control of the first adjustment valve 11 and the second adjustment valve 12 will be described.

  As shown in FIG. 5, the air conditioning system 100A includes an air conditioner 200A and a controller 300. In the air conditioner 200A, the first adjustment valve 11 and the second adjustment valve 12 are provided in the suction pipe 24 of the main circuit 10. The first regulating valve 11 is provided on the upstream side of the accumulator 6, that is, between the evaporator 4 and the accumulator 6. The second adjustment valve 12 is provided downstream of the accumulator 6, that is, between the accumulator 6 and the compressor 1. Each of the first adjustment valve 11 and the second adjustment valve 12 includes, for example, an electronic expansion valve, and is capable of adjusting the opening degree.

  The bypass pipe 24a according to the second embodiment connects between the evaporator 4 and the first adjustment valve 11, and between the second adjustment valve 12 and the compressor 1. That is, in the suction pipe 24 of the second embodiment, the upstream branching means 24b is provided upstream of the first regulating valve 11, and the downstream branching means 24c is provided downstream of the second regulating valve 12.

  FIG. 6 is a block diagram showing a control system of the air conditioner of FIG. As shown in FIG. 6, the control device 50A has a control unit 51A, and the control unit 51A adjusts the respective opening degrees of the first adjustment valve 11 and the second adjustment valve 12. That is, the control unit 51 </ b> A controls the first adjustment valve 11 and the second adjustment valve 12 based on information output from various sensors, a signal output from the operation unit 52, and a signal transmitted from the controller 300. Each opening is configured to be adjusted.

  During the dehumidifying operation, the control unit 51A determines the respective opening degrees of the first adjusting valve 11 and the second adjusting valve 12 according to the change of the suction SH. That is, if the suction SH is equal to or less than the first threshold value, the control unit 51A operates the first adjustment valve 11 and the second adjustment valve 12 in the opening direction to open the first adjustment valve 11 and the second adjustment valve 12. It is designed to increase the degree.

  When the opening degree of the first adjustment valve 11 and the second adjustment valve 12 is increased, the ratio of the first refrigerant sucked into the compressor 1 increases, and the discharge temperature increases. The temperature difference with the temperature of the entering refrigerant increases. Therefore, when trying to obtain the same heat exchange amount in the condenser 2, if the compressor 1 is an inverter compressor, the operating frequency can be lower than when the compressor 1 is a constant speed compressor. Operation efficiency can be improved.

  Further, the control unit 51A calculates the suction SH over time even after increasing the opening degrees of the first adjustment valve 11 and the second adjustment valve 12, and determines whether the calculated suction SH is equal to or more than the second threshold. The judgment is made. Then, when the suction SH reaches the second threshold, the control unit 51A operates the first adjustment valve 11 and the second adjustment valve 12 in the closing direction, and controls the first adjustment valve 11 and the second adjustment valve 12. The opening is reduced.

  In the second embodiment, the first threshold value is a temperature that is a reference of timing for operating the first adjustment valve 11 and the second adjustment valve 12 in the opening direction during the dehumidifying operation, and is set to, for example, 5K. In addition, the second threshold value is a temperature which is a reference for timing when the first adjustment valve 11 and the second adjustment valve 12 once operated in the opening direction are operated in the closing direction during the dehumidifying operation. The second threshold is set to a temperature higher than the first threshold, for example, 15K. The first threshold value and the second threshold value can be appropriately changed according to the configuration of the air conditioner 200A, the installation environment, and the like. The user can set and change the first threshold value and the second threshold value by operating the operation unit 52 or the controller 300.

  In the heating amount increasing mode, the control unit 51A first operates the first adjustment valve 11 and the second adjustment valve 12 in the opening direction during the operation of the compressor 1, and the first adjustment valve 11 and the second adjustment valve 12 Is designed to increase the opening. Then, the control unit 51A controls the first adjustment valve 11 and the second adjustment valve 12 to set the current opening degree until the discharge temperature input from the discharge pipe temperature sensor 31 reaches a close threshold set at, for example, 120 ° C. Let it be maintained.

  Further, after increasing the opening degrees of the first adjustment valve 11 and the second adjustment valve 12, the controller 51 </ b> A sets the first adjustment valve when the discharge temperature input from the discharge pipe temperature sensor 31 rises to the close threshold. 11 and the second regulating valve 12 are operated in the closing direction. Further, after reducing the opening degrees of the first adjustment valve 11 and the second adjustment valve 12, the control unit 51A reduces the discharge temperature input from the discharge pipe temperature sensor 31 to a set open threshold value of, for example, 110 ° C. Until the first adjustment valve 11 and the second adjustment valve 12 maintain the current opening. When the discharge temperature input from the discharge pipe temperature sensor 31 falls to the open threshold, the control unit 51 sets the first solenoid valve 8 and the second solenoid valve 9 to the open state.

  Here, the closing threshold value is a temperature that is a reference for timing when the opening degrees of the first adjustment valve 11 and the second adjustment valve 12 are reduced during the operation in the heating amount increasing mode. The closed threshold may be set to a temperature higher than the closed reference threshold. The opening threshold value is a temperature that is a reference for timing when the opening degrees of the first adjustment valve 11 and the second adjustment valve 12 that are once reduced during operation in the heating amount increasing mode, and is set to a temperature lower than the closing threshold value. Is done. The open threshold may be set to a temperature lower than the close reference temperature and higher than the open reference temperature. The closed threshold value and the open threshold value can be appropriately changed according to the configuration of the air conditioner 200A, the installation environment, and the like. By operating the operation unit 52 or the controller 300, the user can set and change the open threshold value and the close threshold value.

  During the defrosting operation, the control unit 51A first operates the first adjustment valve 11 and the second adjustment valve 12 in the opening direction so as to increase the opening degrees of the first adjustment valve 11 and the second adjustment valve 12. Has become. Thereby, the control unit 51A changes the composition of the non-azeotropic mixed refrigerant to be sucked into the compressor 1, and increases the ratio of the first refrigerant.

  Further, after increasing the degree of opening of the first adjustment valve 11 and the second adjustment valve 12, the controller 51A performs the first adjustment when the discharge temperature input from the discharge pipe temperature sensor 31 reaches the close reference threshold. The valve 11 and the second regulating valve 12 are operated in the closing direction to suppress an increase in the discharge temperature. Further, after the opening degree of the first adjustment valve 11 and the second adjustment valve 12 is reduced, the control unit 51A performs the first adjustment when the discharge temperature input from the discharge pipe temperature sensor 31 falls to the open reference threshold. The degree of opening of the valve 11 and the second regulating valve 12 is increased.

  Here, the closing reference threshold value is a temperature that is a reference of a timing at which the openings of the first adjustment valve 11 and the second adjustment valve 12 are reduced during the defrosting operation, and is set to, for example, 115 ° C. The opening reference threshold value is a temperature that becomes a reference of a timing at which the opening degrees of the first adjustment valve 11 and the second adjustment valve 12 that have once decreased during the defrosting operation are increased. The open reference threshold is set to a temperature lower than the close reference threshold, for example, 105 ° C. The closed reference threshold and the open reference threshold can be changed as appropriate according to the configuration of the air conditioner 200A, the installation environment, and the like. By operating the operation unit 52 or the controller 300, the user can set and change the open reference threshold and the close reference threshold. Other functions of the control unit 51A are the same as those of the control unit 51 of the first embodiment.

(Method of controlling the degree of opening of first solenoid valve 8 and second solenoid valve 9)
FIG. 7 is a flowchart illustrating an operation centering on the dehumidifying operation and the defrosting operation of the air-conditioning apparatus of FIG. 5. FIG. 8 is a flowchart illustrating an operation of the air-conditioning apparatus of FIG. 5 in a heating amount increasing mode. A method of controlling the opening of the first adjustment valve 11 and the second adjustment valve 12 will be described with reference to FIGS. 7 and 8.

  First, an operation control method centering on the dehumidifying operation and the defrosting operation of the air conditioner will be described with reference to FIG. The same operations as those in FIG. 3 are denoted by the same reference numerals, and description thereof is omitted.

  The control unit 51A executes the processing from step S101 to step S103 in the same manner as in the case of FIG. Then, the controller 51A detects that the hot gas solenoid valve 7 is in the open state, and determines that the air-conditioning apparatus 200 is performing the defrosting operation (step S103 / YES), and determines that the first regulating valve 11 is in operation. Then, the second adjustment valve 12 is operated in the opening direction (step S401).

  Next, the control unit 51A executes the processing from step S105 to step S106, as in the case of FIG. Then, when the discharge temperature input from the discharge pipe temperature sensor 31 reaches the close reference threshold (step S105 / YES), the control unit 51A operates the first adjustment valve 11 and the second adjustment valve 12 in the closing direction. (Step S402). Subsequently, the control unit 51A executes the process of step S108 in the same manner as in FIG. 3, and when the discharge temperature input from the discharge pipe temperature sensor 31 falls to the open reference threshold (step S108 / YES). Then, the first control valve 11 and the second control valve 12 are operated in the opening direction (step S403).

  Control unit 51A detects that hot gas solenoid valve 7 is closed, and determines that air-conditioning apparatus 200 is in the dehumidifying operation (step S103 / NO). Execute in the same manner as in the case of 3. If the suction SH is equal to or less than the first threshold value (step S201 / YES), the control unit 51A operates the first adjustment valve 11 and the second adjustment valve 12 in the opening direction (step S501), and illustrates the process of step S203. Execute in the same manner as in the case of 3. Then, when the suction SH reaches the second threshold, the control unit 51A operates the first adjustment valve 11 and the second adjustment valve 12 in the closing direction (Step S502), and returns to the processing of Step S102.

  Next, an operation control method in the heating amount increasing mode of the air conditioner will be described with reference to FIG. Operations that are the same as those in FIG. 4 are denoted by the same reference numerals, and description thereof is omitted.

  When detecting the start of the heating amount increasing mode in Step S102 of FIG. 3 (Step S102 / YES), the control unit 51A determines whether or not the compressor 1 is operating (Step S301). When the compressor 1 is operating or when the compressor 1 starts operating (step S301 / YES), the control unit 51 operates the first adjustment valve 11 and the second adjustment valve 12 in the opening direction. And increase the ratio of the first refrigerant. At that time, the control unit 51A starts time measurement by the heating amount up timer (step S601).

  Next, the control unit 51A executes the processing from step S303 to step S305 in the same manner as in the case of FIG. If the discharge temperature input from the discharge pipe temperature sensor 31 is equal to or higher than the close threshold value (step S303 / YES) and the heating amount up timer has not counted up (step S304 / NO), The first adjustment valve 11 and the second adjustment valve 12 are operated in the closing direction (Step S602).

  Next, the control unit 51A executes the processing from step S307 to step S309 in the same manner as in the case of FIG. Then, when the discharge temperature input from the discharge pipe temperature sensor 31 falls to the open threshold (step S309 / NO), the control unit 51A operates the first adjustment valve 11 and the second adjustment valve 12 in the opening direction. (Step S603), and the process returns to step S303.

  By the way, in the above description, the case where the control unit 51A causes the first adjustment valve 11 and the second adjustment valve 12 to maintain the current opening degree until the discharge temperature reaches the close threshold has been described, but the invention is not limited thereto. Not something. For example, the control unit 51A may finely adjust the degree of opening of the first adjustment valve 11 and the second adjustment valve 12 according to information output from various sensors. Further, in the above description, the case where the control unit 51A causes the first adjustment valve 11 and the second adjustment valve 12 to maintain the current opening degree until the discharge temperature decreases to the opening threshold has been described as an example, but the invention is not limited thereto. Not something. For example, the control unit 51A may finely adjust the degree of opening of the first adjustment valve 11 and the second adjustment valve 12 according to information output from various sensors. This makes it possible to more flexibly adjust the ratio of the first refrigerant in the non-azeotropic refrigerant mixture circulating in the refrigerant circuit.

  As described above, according to the air-conditioning apparatus 200A, by controlling the first adjustment valve 11 and the second adjustment valve 12, respectively, the ratio of the first refrigerant in the non-azeotropic mixed refrigerant to be sucked into the compressor 1 is increased. adjust. Therefore, since the low pressure can be increased, and the high pressure and the temperature of the refrigerant discharged from the compressor can be increased, an efficient operation utilizing the characteristics of the non-azeotropic mixed refrigerant can be realized. . Further, since the first adjustment valve 11 and the second adjustment valve 12 are each an electronic expansion valve whose opening degree can be adjusted, the ratio of the first refrigerant can be adjusted more flexibly.

  That is, the air conditioner 200A increases the opening degree of the first adjustment valve 11 and the opening degree of the second adjustment valve 12 at a predetermined timing, and increases the ratio of the low boiling point refrigerant circulating in the refrigerant circuit, thereby reducing the low pressure. The pressure is increased to increase the circulation amount of the refrigerant in the refrigerant circuit, and the discharge temperature and the high pressure are increased. For this reason, the defrosting time can be reduced, the defrosting efficiency can be increased, and the operating efficiency can be improved.

  Further, when air conditioner 200A includes an inverter compressor as compressor 1, control unit 51A can perform a COP-up operation similarly to control unit 51 of the first embodiment. Here, the control device 50A stores, in the storage unit 53, a frequency adjustment table in which the opening adjustment amounts of the first adjustment valve 11 and the second adjustment valve 12 are associated with the frequency of the compressor 1. Is also good. The frequency adjustment table may be configured so that the frequency of the compressor 1 decreases as the opening adjustment amount increases in a range in which the opening adjustment amount indicates the amount by which the opening is increased. In addition, the frequency adjustment table may be configured such that the frequency of the compressor 1 increases as the opening adjustment amount increases in a range in which the opening adjustment amount indicates the amount by which the opening is reduced. In other words, the control unit 51A adjusts the opening adjustment amounts of the first adjustment valve 11 and the second adjustment valve 12 when adjusting the opening degrees of the first adjustment valve 11 and the second adjustment valve 12, respectively. The frequency of the compressor 1 may be adjusted in light of a table. Other effects and the like are the same as in the first embodiment.

  Each of the above embodiments is a preferred specific example in an air conditioner and an air conditioner system, and the technical scope of the present invention is not limited to these modes. For example, in each of the above-described embodiments, the case where the air conditioners 200 and 200A are dehumidifiers has been described as an example. However, the present invention is not limited to this. Machine. That is, the air conditioners 200 and 200A only need to be air conditioners that can execute at least the dehumidifying operation and the defrosting operation.

  REFERENCE SIGNS LIST 1 compressor, 2 condenser, 3 throttle device, 4 evaporator, 5 fan, 6 accumulator, 7 hot gas solenoid valve, 8 first solenoid valve, 9 second solenoid valve, 10 main circuit, 11 first regulating valve, 12 second regulating valve, 15 hot gas bypass circuit, 20 main pipe, 21 discharge pipe, 22, 23 liquid pipe, 24 suction pipe, 24a bypass pipe, 24b upstream branch means, 24c downstream branch means, 25 hot gas defrost pipe, 25a first branching means, 25b second branching means, 31 discharge pipe temperature sensor, 32 high pressure pressure sensor, 33 suction pipe temperature sensor, 34 low pressure pressure sensor, 50, 50A control unit, 51, 51A control unit, 52 operation unit, 53 storage unit, 100, 100A air conditioning system, 200, 200A air conditioning device, 300 controller.

Claims (14)

A compressor, a condenser, a throttle device, an evaporator, and an accumulator are sequentially connected, and a main circuit in which a non-azeotropic mixed refrigerant including a first refrigerant and a second refrigerant having a higher boiling point than the first refrigerant circulates,
A control device for controlling the main circuit;
Has,
The main circuit includes:
A first regulating valve provided upstream of the accumulator,
A second regulating valve provided downstream of the accumulator,
A bypass pipe connecting between the evaporator and the first regulating valve, between the second regulating valve and the compressor, and bypassing the accumulator;
The control device includes:
By controlling the first adjusting valve and the second adjusting valve, respectively, the ratio of the first refrigerant in the non-azeotropic mixed refrigerant to be sucked into the compressor is adjusted.
Air conditioner. A circuit for connecting between the discharge side of the compressor and the condenser and between the condenser and the expansion device, further comprising a hot gas bypass circuit provided with a hot gas solenoid valve. ,
The control device is for controlling the hot gas bypass circuit,
The air conditioner according to claim 1. The control device includes:
During the defrosting operation in which the hot gas solenoid valve is open,
By opening the first regulating valve and the second regulating valve, the ratio of the first refrigerant in the non-azeotropic mixed refrigerant to be sucked into the compressor is increased.
The air conditioner according to claim 2. The control device includes:
During the defrosting operation, after opening the first adjustment valve and the second adjustment valve,
When the discharge temperature that is the temperature of the refrigerant discharged from the compressor reaches a close reference threshold, the first control valve and the second control valve are closed.
The air conditioner according to claim 3. The control device includes:
During the defrosting operation, after closing the first adjustment valve and the second adjustment valve,
When the discharge temperature falls to an open reference temperature set to a temperature lower than the close reference threshold, the first adjustment valve and the second adjustment valve are opened.
The air conditioner according to claim 4. The control device includes:
When detecting the start of the heating amount up mode to increase the heating amount by the condenser,
By opening the first regulating valve and the second regulating valve, the ratio of the first refrigerant in the non-azeotropic mixed refrigerant to be sucked into the compressor is increased.
The air conditioner according to any one of claims 2 to 5. The control device includes:
In the heating amount increasing mode, after opening the first regulating valve and the second regulating valve,
When the discharge temperature, which is the temperature of the refrigerant discharged from the compressor, rises to a close threshold, the first control valve and the second control valve are closed.
The air conditioner according to claim 6. The control device includes:
In the heating amount up mode, after closing the first adjustment valve and the second adjustment valve,
When the discharge temperature falls to an open threshold set at a temperature lower than the close threshold, the first adjustment valve and the second adjustment valve are opened.
The air conditioner according to claim 7. The control device includes:
During the dehumidifying operation in which the hot gas solenoid valve is closed,
If the suction superheat degree, which is the superheat degree on the suction side of the compressor, is equal to or less than a first threshold value, the non-azeotropic liquid to be sucked into the compressor is opened by opening the first adjustment valve and the second adjustment valve. It is to increase the ratio of the first refrigerant in the mixed refrigerant,
The air conditioner according to any one of claims 2 to 8. The control device includes:
After opening the first regulating valve and the second regulating valve during the dehumidifying operation,
When the suction superheat reaches a second threshold set at a temperature higher than the first threshold, the first control valve and the second control valve are closed.
The air conditioner according to claim 9. The first adjustment valve and the second adjustment valve are solenoid valves having an open state and a closed state, respectively.
The control device includes:
When opening the first adjustment valve and the second adjustment valve, the first adjustment valve and the second adjustment valve are respectively changed from a closed state to an open state.
The air conditioner according to any one of claims 3 to 10. The first adjusting valve and the second adjusting valve are electronic expansion valves each capable of adjusting an opening degree,
The control device includes:
When opening the first adjustment valve and the second adjustment valve, the opening degree of each of the first adjustment valve and the second adjustment valve is increased.
The air conditioner according to any one of claims 3 to 10. The compressor is an inverter compressor whose frequency can be adjusted by an inverter,
The control device includes:
When the first regulating valve and the second regulating valve are opened, the frequency of the compressor is reduced.
The air conditioner according to any one of claims 3 to 12. The main circuit is configured such that air cooled through the evaporator is heated through the condenser.
The air conditioner according to any one of claims 1 to 13.

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