JP6755396B2 - Air conditioner - Google Patents

Description

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

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 is known (see, for example, Patent Document 1). The air conditioner of Patent Document 1 raises the temperature of the air cooled by the evaporator by a condenser acting as a reheater during the dehumidifying operation, and suppresses the temperature drop of the air blown into the room. There is.

By the way, there are a single refrigerant and a mixed refrigerant as the refrigerant that circulates in the refrigerant circuit, and the mixed refrigerant is a non-azeotropic mixed refrigerant in which refrigerants having the same boiling point and a refrigerant having different boiling points are mixed. There is an azeotropic mixed refrigerant. The non-azeotropic mixed refrigerant is a mixture of a low boiling point refrigerant having a relatively low boiling point and a high boiling point refrigerant having a relatively high boiling point.

JP-A-2007-78242

However, when the non-azeotropic mixed refrigerant is simply applied to the conventional air conditioner as in Patent Document 1, the non-azeotropic mixed refrigerant contains a low boiling point refrigerant and a high boiling point refrigerant, so that the low boiling point is low. The discharge temperature is less likely to rise than when the single refrigerant of. That is, the conventional air conditioner has a problem that it cannot perform efficient operation by utilizing the characteristics of the non-azeotropic mixed refrigerant.

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

In the air conditioner according to the present invention, a compressor, a condenser, a drawing device, an evaporator, and an accumulator are sequentially connected, and a non-coborous mixture containing a first refrigerant and a second refrigerant having a boiling point higher than that of the first refrigerant. It has a main circuit through which the refrigerant circulates and a control device that controls the main circuit. The main circuit has a first regulating valve provided on the upstream side of the accumulator and a second adjusting valve provided on the downstream side of the accumulator. The control device has a valve, a bypass pipe that connects between the evaporator and the first regulating valve, a second regulating valve and the compressor, and bypasses the accumulator, and the control device is the first regulating valve. By controlling each of the and the second adjusting valve, the ratio of the first refrigerant in the non-coboiling mixed refrigerant to be sucked into the compressor is adjusted.

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

It is a figure which showed the structure which concerns on the refrigerant circuit of the air-conditioning harmony system which concerns on Embodiment 1 of this invention. It is a block diagram which shows the control system of the air conditioner of FIG. It is a flowchart which shows the operation centering on the dehumidifying operation and the defrosting operation of the air conditioner of FIG. It is a flowchart which shows the operation in the heating amount up mode of the air conditioner of FIG. It is a figure which showed the structure which concerns on the refrigerant circuit of the air-conditioning harmony system which concerns on Embodiment 2 of this invention. It is a block diagram which shows the control system of the air conditioner of FIG. It is a flowchart which shows the operation centering on the dehumidifying operation and the defrosting operation of the air conditioner of FIG. It is a flowchart which shows the operation in the heating amount up mode of the air conditioner of FIG.

Embodiment 1.
FIG. 1 is a diagram showing a configuration related to a refrigerant circuit of the air conditioning harmonization system according to the first embodiment of the present invention. As shown in FIG. 1, the air conditioning system 100 includes an air conditioning device 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 household.

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. There is. The first solenoid valve 8 is provided on the upstream side of the accumulator 6, that is, between the evaporator 4 and the accumulator 6. The second solenoid valve 9 is provided on the downstream side 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 throttle 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 arranged on the high pressure side, a liquid pipe 22 arranged on the high pressure side, a liquid pipe 23 arranged on the low pressure side, and a suction pipe arranged on the low pressure side. It is composed of 24 and.

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 that connects the outflow side of the condenser 2 and the inflow side of the throttle 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 that connects the outflow side of the throttle device 3 and the inflow side of the evaporator 4. A low-pressure two-phase refrigerant flowing out of the drawing device 3 flows through the liquid pipe 23. The suction pipe 24 is a pipe that connects the outflow side of the evaporator 4 and the suction side of the compressor 1. A low-pressure gas refrigerant collected from the evaporator 4 flows through the suction pipe 24.

The suction pipe 24 has a bypass pipe 24a that connects between the evaporator 4 and the first solenoid valve 8 and between the second solenoid valve 9 and the compressor 1 and bypasses the accumulator 6. More specifically, the suction pipe 24 is provided with an upstream branching means 24b upstream of the first solenoid valve 8, that is, between the evaporator 4 and the first solenoid valve 8. Further, the suction pipe 24 is provided with a downstream branching means 24c downstream of the second solenoid valve 9, that is, between the second solenoid valve 9 and the compressor 1. That is, the upstream branching means 24b and the downstream branching means 24c are connected by a 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 throttle device 3. The hot gas bypass circuit 15 includes a hot gas defrost pipe 25 and a hot gas solenoid valve 7. More specifically, the first branching means 25a is provided in the middle of the discharge pipe 21, and the second branching means 25b is provided in the middle of the liquid pipe 22. That is, the first branch means 25a and the second branch means 25b are connected by the hot gas defrost pipe 25, and the hot gas solenoid valve 7 is arranged in the hot gas defrost pipe 25.

The air conditioner 200 of the first embodiment uses a first refrigerant and a second refrigerant having a boiling point higher than that of the first refrigerant as a refrigerant for circulating the refrigerant circuit formed by the main circuit 10 and the hot gas bypass circuit 15. It uses a non-azeotropic mixed refrigerant containing. In the non-azeotropic mixed refrigerant, the first refrigerant is a low boiling point refrigerant having a relatively low boiling point, and the second refrigerant is a high boiling point refrigerant having a relatively high boiling point.

More specifically, the non-azeotropic mixed refrigerant is, for example, R407C or R448A. The non-co-boiling mixed refrigerant is a mixed refrigerant of R32, R125, R134a, R1234yf, and CO _2, and the condition that the ratio XR32 (wt%) of R32 is "33 <XR32 <39" and R125. The condition that the ratio XR125 (wt%) of R134a is "27 <XR125 <33", the condition that the ratio XR134a (wt%) of R134a is "11 <XR134a <17", and the ratio XR1234yf (wt%) of R1234yf are The condition that "11 <XR1234yf <17", the condition that the ratio XCO ₂ (wt%) of CO ₂ is "3 <XCO ₂ <9", and the sum of XR32, XR125, XR134a, XR1234yf, and XCO ₂ are It may be a refrigerant that satisfies all of the conditions of 100.

The compressor 1 compresses the refrigerant. The compressor 1 may be a constant speed compressor or an inverter compressor including 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 air. The throttle device 3 is composed of, for example, an electronic expansion valve, and expands the refrigerant condensed in the condenser 2. The evaporator 4 evaporates the refrigerant expanded in the drawing device 3. The evaporator 4 is composed of, for example, a fin-and-tube type 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, since the liquid is incompressible, a large pressure is generated inside the compressor 1 and a violent 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 lowered, so that the compressor 1 may fail due to poor lubrication. In order to prevent such inconvenience, an accumulator 6 is provided in the main circuit 10 of the air conditioner 200. Whether or not 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 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 is for separating the refrigerant flowing into the container into a gas and a liquid, and returning the gas refrigerant to the compressor 1. The hot gas solenoid valve 7 is a solenoid valve that is in an open state for passing the refrigerant when it is in the ON state and in a closed state for shutting off the refrigerant when it is 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.

The first solenoid valve 8 and the second solenoid valve 9 are solenoid valves that are in an open state for passing the refrigerant when in the ON state and in a closed state for shutting off the refrigerant when in the OFF state, respectively. When the first solenoid valve 8 and the second solenoid valve 9 are in the ON state, the refrigerant that has passed through the evaporator 4 passes through the accumulator 6. The first solenoid valve 8 corresponds to the "first regulating valve" of the present invention, and the second solenoid valve 9 corresponds to the "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 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 the condensation of the refrigerant in the condenser 2, that is, the release of heat.

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

The air conditioner 200 has a main circuit 10, a hot gas bypass circuit 15, and a control device 50 that controls the fan 5. That is, the control device 50 controls the operation of various actuators in the air conditioner 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. It is to be managed. For example, the control device 50 adjusts the open / closed state of each of the first solenoid valve 8 and the second solenoid valve 9 to adjust the ratio of the first refrigerant in the non-azeotropic mixed refrigerant to be sucked into the compressor 1. Is. Hereinafter, the ratio of the first refrigerant in the non-azeotropic mixed refrigerant to be sucked into the compressor 1 is also simply referred to as “the ratio of the first refrigerant”.

(Basic flow of refrigerant)
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 passes through the discharge pipe 21 and enters the condenser 2. The gas refrigerant contained in the condenser 2 releases heat and liquefies by exchanging heat with air. The refrigerant liquefied by the condenser 2 flows into the throttle device 3 through the liquid pipe 22, and is depressurized by the throttle device 3 to be in a gas-liquid two-phase state. Then, the refrigerant in the gas-liquid two-phase state in the drawing device 3 flows into the evaporator 4 through the liquid pipe 23, and releases cold heat by exchanging heat with air in the evaporator 4. To 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 conditioner 200, the refrigerating cycle is formed by repeating the circulation process as described above for the refrigerant in the refrigerant circuit.

By the way, in the air conditioner 200, as shown by the white arrow of the alternate long and short dash line in FIG. 1, the indoor air sucked from the room passes through the evaporator 4 and then the condenser 2. .. Therefore, the room air is cooled as it passes through the evaporator 4 and warmed as it passes through the condenser 2. That is, when the indoor air passes through the evaporator 4, it receives cold heat and becomes below the dew point. Therefore, a part of the indoor air condenses on the evaporator 4, and is cooled and dehumidified. On the other hand, the indoor air that has passed through the evaporator 4 receives heat when passing through the condenser 2, reaches a predetermined temperature, and is discharged into the room 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 as it passes 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 input operations related to various settings such as a target temperature and a target pressure, and outputs a signal corresponding to the content of the input operations to the control unit 51. The storage unit 53 includes a RAM (Random Access Memory) that stores various types of data, and a ROM (Read Only Memory) that stores a program or the like for the control unit 51 to perform control in each operation mode. Has been done.

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

The control unit 51 causes the air conditioner 200 to perform a dehumidifying operation, an operation in the heating amount up mode, and a defrosting operation. The control unit 51 controls the operation 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. Is.

For example, the control unit 51 appropriately controls the open / closed state of the first solenoid valve 8 and the second solenoid valve 9 according to the program in the ROM of the storage unit 53, and adjusts the composition of the refrigerant to be sucked 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 to control the composition of the refrigerant in the refrigerant circuit, that is, the refrigerant circuit. It changes the ratio of the circulating low boiling point 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 pressure measured by the low pressure pressure sensor 34 increases, the amount of the refrigerant circulating in the refrigerant circuit increases, and the value of the high pressure pressure measured by the high pressure pressure sensor 32 and the discharge 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 becomes large, the defrosting time in the defrosting operation can be shortened, and the dehumidifying efficiency can be improved. The dehumidifying efficiency in the first embodiment is determined by using a value obtained by dividing the dehumidifying operation time by the defrosting time (dehumidifying operation time / defrosting 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 the operation of the air conditioner 200, an OFF switch for stopping the operation of the air conditioner 200, a heating amount adjusting switch for increasing the heating amount, and the like. There is. The controller 300 accepts an input operation by the user and transmits a signal according to the content of the input operation to the control unit 51.

(During dehumidifying operation)
The control unit 51 determines the open / closed state of the first solenoid valve 8 and the second solenoid valve 9 by observing whether the suction SH is higher or lower than the first threshold value during the dehumidifying operation. More specifically, the control unit 51 obtains the suction SH by subtracting the low pressure pressure saturation temperature from the suction temperature input from the suction pipe temperature sensor 33. The low pressure pressure saturation temperature is a value obtained by converting the low pressure pressure value input from the low pressure pressure sensor 34 into a saturation temperature. For example, the storage unit 53 stores a conversion table which is table information relating the low pressure pressure and the saturation temperature, and the control unit 51 illuminates the low pressure pressure information input from the low pressure pressure sensor 34 with the conversion table. Therefore, the low pressure saturation temperature is obtained. Then, the control unit 51 determines whether or not the obtained intake SH is equal to or less than the first threshold value, and if the intake SH is equal to or less than the first threshold value, the first solenoid valve 8 and the second solenoid valve 9 are opened. It is to make it a 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, so that the temperature of the condenser 2 and the condenser 2 are affected. The temperature difference from the temperature of the incoming refrigerant becomes large. Therefore, when trying to obtain the same amount of heat exchange 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 than when the compressor 1 is a constant speed compressor. Since the operating frequency can be lowered, the operating efficiency can be improved. That is, according to the air conditioner 200 equipped with the inverter compressor as the compressor 1, the COP (Coefficient of Performance: coefficient of performance) can be increased.

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, the control unit 51 compresses when the first solenoid valve 8 and the second solenoid valve 9 are opened, or when the waiting time elapses after opening the first solenoid valve 8 and the second solenoid valve 9. The frequency of the machine 1 may be lowered. 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, the installation environment, or the like. 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 also perform such a COP up operation during the defrosting operation and the operation in the heating amount up mode.

Further, the control unit 51 obtains the suction SH over time even after the first solenoid valve 8 and the second solenoid valve 9 are opened, and determines whether or not the obtained suction SH is equal to or higher than the second threshold value. Is. Then, the control unit 51 closes the first solenoid valve 8 and the second solenoid valve 9 when the suction SH reaches the second threshold value.

Here, the first threshold value is a temperature that serves as a reference for the 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 that serves as a reference for the timing of closing the first solenoid valve 8 and the second solenoid valve 9 that have been once opened 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 contents of the air conditioner 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.

(When operating in the heating amount up mode)
The user can perform the setting operation of the heating amount up mode for increasing the heating amount by the condenser 2 via the operation unit 52 or the controller 300. In the heating amount up mode, the heating capacity is increased by the control unit 51 controlling the opening and closing of the first solenoid valve 8 and the second solenoid valve 9 according to the change in the discharge temperature measured by the discharge pipe temperature sensor 31. This is an operation mode that adjusts to realize rapid dehumidification operation. Here, the rapid dehumidification operation is an operation in which an air environment having a desired humidity is provided in a time faster than a normal dehumidification operation by supplying air having a low relative humidity into the room.

The heating amount up mode setting operation includes an operation of instructing the start of the heating amount up mode, an operation of setting the time to start the heating amount up mode, or a time until the heating amount up mode is started. Operations etc. are included. The operation for setting the heating amount up mode also includes an operation for setting the heating amount up duration, which is the time for the control unit 51 to continue the control in the heating amount up mode. That is, the user can set and change the heating amount increase duration by operating the operation unit 52 or the controller 300.

In the heating amount up mode, the control unit 51 first opens the first solenoid valve 8 and the second solenoid valve 9 during the operation of the compressor 1. More specifically, the control unit 51 detects the start of the heating amount up mode according to the signal from the operation unit 52 or the controller 300 or the setting content in the operation unit 52 or the controller 300. The control unit 51 opens the first solenoid valve 8 and the second solenoid valve 9 when the start of the heating amount up mode is detected while the compressor 1 is operating. Further, when the control unit 51 detects the start of the heating amount up mode, if the compressor 1 is stopped, the control unit 51 waits until the compressor 1 starts the operation, and when the compressor 1 starts the operation. , 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 pressure rises, the amount of the refrigerant circulating in the refrigerant circuit increases, and the high pressure pressure and the discharge temperature rise. 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 value set to, for example, 120 ° C.

The control unit 51 opens the first solenoid valve 8 and the second solenoid valve 9, and then when the discharge temperature input from the discharge pipe temperature sensor 31 rises to the closed threshold value, the first solenoid valve 8 and the second solenoid valve 9 The second solenoid valve 9 is closed. Further, after the first solenoid valve 8 and the second solenoid valve 9 are closed, 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 this is done, the first solenoid valve 8 and the second solenoid valve 9 are kept in the closed state. Then, 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 drops to the open threshold value.

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

In addition, the control unit 51 has a heating amount up timer (not shown) that measures the elapsed time from 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 timing by the heating amount up timer. Then, the control unit 51 heats when the heating amount up timer counts up, that is, when the heating amount up time elapses after the first solenoid valve 8 and the second solenoid valve 9 are first opened. The amount up mode is ended and the normal operation is started. In the first embodiment, the normal operation corresponds to the normal dehumidifying operation.

(During defrosting operation: During hot gas defrost)
The control unit 51 determines whether or not the air conditioner 200 is in the 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 in the open state. That is, if the hot gas solenoid valve 7 is in the open state, the control unit 51 determines that the defrosting operation is in progress, and if the hot gas solenoid valve 7 is in the closed state, the defrosting operation is not in progress. It is designed to judge. 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 in progress.

When the control unit 51 determines that the air conditioner 200 is in the defrosting operation, the control unit 51 opens the first solenoid valve 8 and the second solenoid valve 9 and causes the compressor 1 to suck the non-azeotropic mixed refrigerant. The composition is changed to increase the ratio of the first refrigerant. Further, the control unit 51 opens the first solenoid valve 8 and the second solenoid valve 9 and then reaches the closing reference threshold when the discharge temperature input from the discharge pipe temperature sensor 31 reaches the closing reference threshold value. The valve 8 and the second solenoid valve 9 are closed once to suppress an increase in the discharge temperature. Further, the control unit 51 closes the first solenoid valve 8 and the second solenoid valve 9, and then when the discharge temperature input from the discharge pipe temperature sensor 31 drops to the open reference threshold value, the first solenoid valve The valve 8 and the second solenoid valve 9 are opened again.

Here, the closing reference threshold value is a temperature that serves as a reference for the 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 open reference threshold value is a temperature that serves as a reference for the timing of reopening the first solenoid valve 8 and the second solenoid valve 9 that were once closed during the defrosting operation. The open reference threshold is set to a temperature lower than the closed reference threshold, for example 105 ° C. The open reference threshold value and the closed reference threshold value can be appropriately changed according to the configuration contents of the air conditioner 200, the installation environment, and the like. The user can set and change the open reference threshold value and the closed reference threshold value by operating the operation unit 52 or the controller 300.

The control unit 51 has a function of determining whether or not the defrosting operation end condition is satisfied, and ends the defrosting operation when the defrosting operation end condition is satisfied. For example, the control unit 51 may be configured to start the defrosting operation by presuming that the evaporator 4 is in the frosted state when the dehumidifying operation is continuously performed for a predetermined set time. When adopting such a configuration, for example, a temperature sensor including a thermistor is provided at the air suction port of the air conditioner 200, and the control unit 51 dehumidifies the set time of the dehumidifying operation based on the measured temperature of the temperature sensor. The defrosting time, which is the time for continuing the frost operation, may be determined. Then, the control unit 51 may start the time counting when the defrosting operation is started, and end the defrosting operation when the defrosting time elapses. In this case, when the defrosting time elapses, the defrosting 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. When adopting such a configuration, for example, an evaporation temperature sensor including a thermistor or the like may be provided in the evaporator 4. Then, the control unit 51 starts the defrosting operation when the temperature measured by the evaporation temperature sensor drops to the start threshold value, and then defrosts when the temperature measured by the evaporation temperature sensor rises to the end threshold value. The operation may be terminated. In this case, when the temperature measured by the evaporation temperature sensor rises to the end threshold value, the defrosting operation end condition is satisfied. The end threshold is set to a temperature higher than the start threshold.

(Method of opening / closing control of the first solenoid valve 8 and the second solenoid valve 9 )
FIG. 3 is a flowchart showing an operation centered on the dehumidifying operation and the defrosting operation of the air conditioner of FIG. FIG. 4 is a flowchart showing the operation of the air conditioner of FIG. 1 in the heating amount up mode. A method of opening / closing control of the first solenoid valve 8 and the second solenoid valve 9 will be described with reference to FIGS. 3 and 4. First, with reference to FIG. 3, an operation control method centering on the dehumidifying operation and the defrosting operation of the air conditioner will be described.

The control unit 51 determines whether or not the compressor 1 is in operation (step S101), and if the compressor 1 is not in operation, waits until the compressor 1 starts operation (step S101 / NO). ). When the control unit 51 detects the start of the heating amount up mode (step S102 / YES) during the operation of the compressor 1 (step S101 / YES), the control unit 51 shifts to the heating amount up mode (see FIG. 4). If the control unit 51 has not detected the start of the heating amount up mode during the operation of the compressor 1 (step S101 / YES) (step S102 / NO), is the air conditioner 200 in the defrosting operation? It is determined whether or not (step S103).

(Defrosting operation)
When the control unit 51 detects that the hot gas solenoid valve 7 is in the open state and determines that the air conditioner 200 is in the defrosting operation (step S103 / YES), the first solenoid valve 8 and the first solenoid valve 7 are determined. 2 By opening the solenoid valve 9, the ratio of the first refrigerant is increased (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 closing reference threshold value (step S105). If the discharge temperature is less than the closing reference threshold value (step S105 / NO), the control unit 51 determines whether or not the defrosting operation end condition is satisfied (step S106). If the control unit 51 satisfies the defrosting operation end condition (step S106 / YES), the control unit 51 returns to the process of step S102. If the control unit 51 does not satisfy the defrosting operation end condition (step S106 / NO), the control unit 51 returns to the process of step S105.

On the other hand, when the discharge temperature reaches the closing reference threshold value (step S105 / YES), the control unit 51 closes the first solenoid valve 8 and the second solenoid valve 9 to suppress the 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 less than the open reference threshold value (step S108).

If the discharge temperature is higher than the open reference threshold value, 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, the control unit 51 sets the defrosting operation end condition (step S108 / NO) after closing the first solenoid valve 8 and the second solenoid valve 9 in step S107 and before the discharge temperature drops to the open reference threshold value. If the condition is satisfied, the process returns to the process of step S102.

The control unit 51 opens the first solenoid valve 8 and the second solenoid valve 9 when the discharge temperature drops to the open reference threshold value (step S108 / YES) (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), the control unit 51 returns to the process of step S102, and if the defrosting operation end condition is not satisfied (step S110 / NO), the control unit 51 returns to the process of step S105.

(Dehumidifying operation)
When the control unit 51 detects that the hot gas solenoid valve 7 is in the closed state and determines that the air conditioner 200 is in the dehumidifying operation (step S103 / NO), the control unit 51 obtains the suction SH and obtains the obtained suction. It is determined whether or not SH is equal to or less than the first threshold value (step S201).

When the suction SH is higher than the first threshold value (step S201 / NO), the control unit 51 is considered not to cause liquid compression in the compressor 1, so that the first solenoid valve 8 and the second solenoid valve 9 are set. 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 value (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 higher than the second threshold value (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 process of step S102.

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

The control unit 51 opens the first solenoid valve 8 and the second solenoid valve 9 when the compressor 1 is in operation or when the compressor 1 starts operation (step S301 / YES), thereby causing the refrigerant. The composition of the first refrigerant is changed to increase the ratio of the first refrigerant. At that time, the control unit 51 starts timing 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 closed threshold value (step S303). If the discharge temperature is lower than the closed threshold value, 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 rises to the open threshold value (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, the control unit 51 closes the first solenoid valve 8 and the second solenoid valve 9 (step S306) unless the heating amount up timer counts up (step S304 / NO).

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 or not the discharge temperature input from the discharge pipe temperature sensor 31 is equal to or lower than the open threshold value. Determine (step S309).

If the discharge temperature is higher than the open threshold value (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 process of step S307. On the other hand, when the discharge temperature drops to the open threshold value (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 conditioner 200, by controlling the first solenoid valve 8 and the second solenoid valve 9, the ratio of the first refrigerant in the non-azeotropic mixed refrigerant to be sucked into the compressor 1 is determined. adjust. Therefore, the low pressure can be raised and the high pressure and the temperature of the refrigerant discharged from the compressor 1 can be raised, so that efficient operation utilizing the characteristics of the non-azeotropic mixed refrigerant can be realized. it can.

By the way, in the conventional air conditioner, when a non-azeotropic mixed refrigerant is applied, the discharge temperature is less likely to rise than when a single refrigerant having a low boiling point is applied, so that the evaporator 4 is defrosted during the defrosting operation. There is a problem that the amount of heat for performing is insufficient and it takes time to complete the defrosting. In this respect, the air conditioner 200 of the first embodiment opens the first solenoid valve 8 and the second solenoid valve 9 during the defrosting operation to increase the ratio of the first refrigerant which is a low boiling point refrigerant. Can be done. 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 becomes large, so that the defrosting time can be shortened. Then, since the ratio of the defrosting time to the dehumidifying operation time can be reduced, the defrosting efficiency can be improved.

Further, in the heating amount up 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. As a result, the control unit 51 can adjust the amount of heat exchange of the condenser 2 that acts as a reheater, so that rapid dehumidification operation can be realized. In addition, when the air conditioner 200 is equipped with an inverter compressor as the compressor 1, the control unit 51 can perform a 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, the control unit 51 opens the first solenoid valve 8 and the second solenoid valve 9, and then when the discharge temperature, which is the temperature of the refrigerant discharged from the compressor, reaches the closing reference threshold value, the first solenoid valve Since the valve 8 and the second solenoid valve 9 are closed, it is possible to suppress an excessive rise in the discharge temperature. Further, 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 conditioning device 200 improves the efficiency of air conditioning control by simple control. Can be planned.

That is, the air conditioner 200 opens the first solenoid valve 8 and the second solenoid valve 9 at a predetermined timing to increase the ratio of the low boiling point refrigerant circulating in the refrigerant circuit to raise the low pressure pressure and raise the refrigerant circuit. The amount of refrigerant circulating inside is increased, and the discharge temperature and high-pressure pressure are increased. Therefore, the defrosting time can be shortened, the defrosting efficiency can be increased, and the operating efficiency can be improved.

Embodiment 2.
FIG. 5 is a diagram showing a configuration related to the refrigerant circuit of the air conditioning harmonization system according to the second embodiment of the present invention. As shown in FIG. 5, the configuration of the air conditioning system 100A of the second embodiment is the same as that of the air conditioning system 100 of the first embodiment described above, but the configuration of the refrigerant circuit is different. That is, the main circuit 10 of the air conditioner 200A is characterized in that it has a first regulating valve 11 and a 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 omitted with reference to the same reference numerals, and the configurations and operations particularly related to the control of the first regulating valve 11 and the second regulating valve 12 will be described below.

As shown in FIG. 5, the air conditioning system 100A includes an air conditioning device 200A and a controller 300. In the air conditioner 200A, the suction pipe 24 of the main circuit 10 is provided with the first regulating valve 11 and the second regulating valve 12. 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 regulating valve 12 is provided on the downstream side of the accumulator 6, that is, between the accumulator 6 and the compressor 1. The first regulating valve 11 and the second regulating valve 12 are each composed of, for example, an electronic expansion valve, and the opening degree can be adjusted.

The bypass pipe 24a of the second embodiment connects between the evaporator 4 and the first regulating valve 11 and between the second regulating valve 12 and the compressor 1. That is, the suction pipe 24 of the second embodiment is provided with the upstream branching means 24b upstream of the first regulating valve 11 and the downstream branching means 24c 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 opening degree of each of the first adjusting valve 11 and the second adjusting valve 12. That is, the control unit 51A of the first adjustment valve 11 and the second adjustment valve 12 based on the information output from various sensors, the signal output from the operation unit 52, the signal transmitted from the controller 300, and the like. It is configured to adjust each opening.

During the dehumidifying operation, the control unit 51A determines the opening degree of each 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 regulating valve 11 and the second regulating valve 12 in the opening direction to open the first regulating valve 11 and the second regulating valve 12. It is designed to increase the degree.

When the opening degree of the first regulating valve 11 and the second regulating valve 12 is increased, the ratio of the first refrigerant sucked into the compressor 1 increases and the discharge temperature rises, so that the temperature of the condenser 2 and the condenser 2 are increased. The temperature difference from the temperature of the incoming refrigerant becomes large. 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 lowered as compared with the case where the compressor 1 is a constant speed compressor. The operating efficiency can be improved.

Further, the control unit 51A obtains 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 or not the obtained suction SH is equal to or higher than the second threshold value. It is designed to judge. Then, when the suction SH reaches the second threshold value, the control unit 51A operates the first regulating valve 11 and the second regulating valve 12 in the closing direction to form the first regulating valve 11 and the second regulating valve 12. The opening is designed to be small.

In the second embodiment, the first threshold value is a temperature that serves as a reference for the timing of operating the first regulating valve 11 and the second regulating valve 12 in the opening direction during the dehumidifying operation, and is set to, for example, 5K. The second threshold value is a temperature that serves as a reference for the timing at which the first regulating valve 11 and the second regulating valve 12, which are 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 contents 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 up mode, the control unit 51A first operates the first adjusting valve 11 and the second adjusting valve 12 in the opening direction while the compressor 1 is operating, and first, the first adjusting valve 11 and the second adjusting valve 12 The opening degree of is increased. Then, the control unit 51A adjusts the current opening degree to the first regulating valve 11 and the second regulating valve 12 until the discharge temperature input from the discharge pipe temperature sensor 31 reaches a closed threshold value set to, for example, 120 ° C. To maintain.

Further, the control unit 51A increases the opening degree of the first adjusting valve 11 and the second adjusting valve 12, and then when the discharge temperature input from the discharge pipe temperature sensor 31 rises to the closed threshold value, the first adjusting valve The 11 and the second regulating valve 12 are operated in the closing direction. Further, after reducing the opening degree of the first adjusting valve 11 and the second adjusting valve 12, the control unit 51A reduces the discharge temperature input from the discharge pipe temperature sensor 31 to, for example, a set open threshold value of 110 ° C. Until this is done, the first regulating valve 11 and the second regulating valve 12 are allowed to maintain the current opening degree. Then, 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 drops to the open threshold value.

Here, the closed threshold value is a temperature that serves as a reference for timing for reducing the opening degree of the first regulating valve 11 and the second regulating valve 12 during operation in the heating amount up mode. The closed threshold value may be set to a temperature higher than the closed reference threshold value. The open threshold value is a temperature that serves as a reference for timing for increasing the opening degree of the first regulating valve 11 and the second regulating valve 12 that have been once reduced during operation in the heating amount up mode, and is set to a temperature lower than the closed threshold value. Will be done. The open threshold value may be set to a temperature lower than the closing reference temperature and higher than the opening reference temperature. The closed threshold value and the open threshold value can be appropriately changed according to the configuration contents of the air conditioner 200A, the installation environment, and the like. The user can set and change the open threshold value and the closed threshold value by operating the operation unit 52 or the controller 300.

During the defrosting operation, the control unit 51A first operates the first adjusting valve 11 and the second adjusting valve 12 in the opening direction so as to increase the opening degree of the first adjusting valve 11 and the second adjusting valve 12. It has become. As a result, the control unit 51A changes the composition of the non-azeotropic mixed refrigerant to be sucked into the compressor 1 to increase the ratio of the first refrigerant.

Further, the control unit 51A makes the first adjustment when the discharge temperature input from the discharge pipe temperature sensor 31 reaches the closing reference threshold value after increasing the opening degrees of the first adjustment valve 11 and the second adjustment valve 12. The valve 11 and the second adjusting valve 12 are operated in the closing direction to suppress an increase in the discharge temperature. Further, the control unit 51A makes the first adjustment when the discharge temperature input from the discharge pipe temperature sensor 31 drops to the open reference threshold value after reducing the opening degrees of the first adjustment valve 11 and the second adjustment valve 12. The opening degree of the valve 11 and the second adjusting valve 12 is increased.

Here, the closing reference threshold value is a temperature that serves as a reference for timing for reducing the opening degree of the first regulating valve 11 and the second regulating valve 12 during the defrosting operation, and is set to, for example, 115 ° C. The open reference threshold value is a temperature that serves as a reference for timing for increasing the opening degree of the first regulating valve 11 and the second regulating valve 12, which have been once reduced during the defrosting operation. The open reference threshold is set to a temperature lower than the closed reference threshold, for example 105 ° C. The closed reference threshold value and the open reference threshold value can be appropriately changed according to the configuration contents of the air conditioner 200A, the installation environment, and the like. The user can set and change the open reference threshold value and the closed reference threshold value by operating the operation unit 52 or the controller 300. Other functions of the control unit 51A are the same as those of the control unit 51 of the first embodiment.

(Method of adjusting the opening degree of the first adjusting valve 11 and the second adjusting valve 12 )
FIG. 7 is a flowchart showing an operation centered on the dehumidifying operation and the defrosting operation of the air conditioner of FIG. FIG. 8 is a flowchart showing the operation of the air conditioner of FIG. 5 in the heating amount up mode. A method of adjusting the opening degree of the first adjusting valve 11 and the second adjusting valve 12 will be described with reference to FIGS. 7 and 8.

First, with reference to FIG. 7, an operation control method centering on the dehumidifying operation and the defrosting operation of the air conditioner will be described. The same reference numerals are used for the operations equivalent to those in FIG. 3, and the description thereof will be omitted.

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

Next, the control unit 51A executes the processes from step S105 to step S106 in the same manner as in the case of FIG. Then, when the discharge temperature input from the discharge pipe temperature sensor 31 reaches the closing reference threshold value (step S105 / YES), the control unit 51A operates the first adjusting valve 11 and the second adjusting 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 the case of FIG. 3, and when the discharge temperature input from the discharge pipe temperature sensor 31 drops to the open reference threshold value (step S108 / YES). , The first regulating valve 11 and the second regulating valve 12 are operated in the opening direction (step S403).

Further, when the control unit 51A detects that the hot gas solenoid valve 7 is in the closed state and determines that the air conditioner 200 is in the dehumidifying operation (step S103 / NO), the process of step S201 is shown. It is executed 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 regulating valve 11 and the second regulating valve 12 in the opening direction (step S501), and processes the step S203. It is executed in the same manner as in the case of 3. Then, when the suction SH reaches the second threshold value, the control unit 51A operates the first regulating valve 11 and the second regulating valve 12 in the closing direction (step S502), and returns to the process of step S102.

Next, the operation control method in the heating amount up mode of the air conditioner will be described with reference to FIG. The same reference numerals are used for the operations equivalent to those in FIG. 4, and the description thereof will be omitted.

When the control unit 51A detects the start of the heating amount up mode in step S102 of FIG. 3 (step S102 / YES), the control unit 51A determines whether or not the compressor 1 is in operation (step S301). The control unit 51 operates the first adjusting valve 11 and the second adjusting valve 12 in the opening direction when the compressor 1 is in operation or when the compressor 1 starts operation (step S301 / YES). , Increase the ratio of the first refrigerant. At that time, the control unit 51A starts timing by the heating amount up timer (step S601).

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

Next, the control unit 51A executes the processes 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 drops to the open threshold value (step S309 / NO), the control unit 51A operates the first adjusting valve 11 and the second adjusting valve 12 in the opening direction. (Step S603), the process returns to the process of step S303.

By the way, in the above description, the case where the control unit 51A causes the first adjusting valve 11 and the second adjusting valve 12 to maintain the current opening degree until the discharge temperature reaches the closing threshold is illustrated, but the present invention is limited to this. It's not a thing. For example, the control unit 51A may finely adjust the opening degrees of the first adjusting valve 11 and the second adjusting valve 12 according to information output from various sensors and the like. Further, in the above description, the case where the control unit 51A causes the first adjusting valve 11 and the second adjusting valve 12 to maintain the current opening degree until the discharge temperature drops to the open threshold value has been illustrated, but the present invention is limited to this. It's not something. For example, the control unit 51A may finely adjust the opening degrees of the first adjusting valve 11 and the second adjusting valve 12 according to information output from various sensors and the like. In this way, the ratio of the first refrigerant in the non-azeotropic mixed refrigerant circulating in the refrigerant circuit can be adjusted more flexibly.

As described above, according to the air conditioner 200A, by controlling the first regulating valve 11 and the second regulating valve 12, the ratio of the first refrigerant in the non-azeotropic mixed refrigerant to be sucked into the compressor 1 is determined. adjust. Therefore, the low pressure can be raised and the high pressure and the temperature of the refrigerant discharged from the compressor can be raised, so that efficient operation utilizing the characteristics of the non-azeotropic mixed refrigerant can be realized. .. Further, since the first regulating valve 11 and the second regulating valve 12 are electronic expansion valves whose opening degrees can be adjusted, respectively, the ratio of the first refrigerant can be adjusted more flexibly.

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

Further, when the air conditioner 200A is equipped with an inverter compressor as the compressor 1, the control unit 51A can perform the COP up operation in the same manner as the 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 degree adjustment amounts of the first adjustment valve 11 and the second adjustment valve 12 and the frequency of the compressor 1 are associated with each other. May be good. The frequency adjustment table may be configured so that the frequency of the compressor 1 decreases as the opening degree adjusting amount increases within the range in which the opening degree adjusting amount indicates the amount of increasing the opening degree. Further, the frequency adjustment table may be configured so that the frequency of the compressor 1 increases as the opening degree adjusting amount increases within the range in which the opening degree adjusting amount indicates the amount of decreasing the opening degree. That is, when the control unit 51A adjusts the opening degree of each of the first adjusting valve 11 and the second adjusting valve 12, the control unit 51A adjusts the frequency of each opening degree adjusting amount of the first adjusting valve 11 and the second adjusting valve 12. The frequency of the compressor 1 may be adjusted in the light of the table. Other effects and the like are the same as in the first embodiment.

Each of the above embodiments is a suitable specific example in an air conditioner and an air conditioner system, and the technical scope of the present invention is not limited to these embodiments. For example, in each of the above embodiments, the case where the air conditioners 200 and 200A are dehumidifiers is illustrated, but the present invention is not limited to this, and the air conditioners 200 and 200A are air conditioners having a function of performing a heating operation or a cooling operation. It may be a machine. That is, the air conditioners 200 and 200A may be air conditioners capable of performing at least dehumidifying operation and defrosting operation.

1 Compressor, 2 Condenser, 3 Squeezer, 4 Evaporator, 5 Fan, 6 Accumulator, 7 Hot Gas Electromagnetic Valve, 8 1st Electromagnetic Valve, 9 2nd Electromagnetic Valve, 10 Main Circuit, 11 1st Adjusting Valve, 12 2nd 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 branching means, 24c downstream branching means, 25 hot gas defrost piping, 25a 1st branching means, 25b 2nd 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 device, 51, 51A control unit, 52 operation unit, 53 Storage unit, 100, 100A air conditioner, 200, 200A air conditioner, 300 controller.

Claims (14)

A main circuit in which a compressor, a condenser, a drawing device, an evaporator, and an accumulator are sequentially connected, and a non-azeotropic mixed refrigerant containing a first refrigerant and a second refrigerant having a boiling point higher than that of the first refrigerant circulates.
A control device that controls the main circuit and
Have,
The main circuit
The first regulating valve provided on the upstream side of the accumulator and
A second regulating valve provided on the downstream side of the accumulator and
It has a bypass pipe that connects between the evaporator and the first regulating valve, and between the second regulating valve and the compressor, and bypasses the accumulator.
The control device is
By controlling the first regulating valve and the second regulating valve, respectively, the ratio of the first refrigerant to the non-azeotropic mixed refrigerant to be sucked into the compressor is adjusted.
Air conditioner. It is a circuit that connects between the discharge side of the compressor and the condenser, and between the condenser and the throttle device, and further has a hot gas bypass circuit provided with a hot gas solenoid valve. ,
The control device controls the hot gas bypass circuit.
The air conditioner according to claim 1. The control device is
During the defrosting operation when 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 is
After opening the first adjusting valve and the second adjusting valve during the defrosting operation,
When the discharge temperature, which is the temperature of the refrigerant discharged from the compressor, reaches the closing reference threshold value, the first adjusting valve and the second adjusting valve are closed.
The air conditioner according to claim 3. The control device is
After closing the first adjusting valve and the second adjusting valve during the defrosting operation,
The first regulating valve and the second regulating valve are opened when the discharge temperature drops to an open reference temperature set to a temperature lower than the closing reference threshold.
The air conditioner according to claim 4. The control device is
When the start of the heating amount up mode for increasing the heating amount by the condenser is detected,
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 is
After opening the first regulating valve and the second regulating valve in the heating amount up mode,
The first regulating valve and the second regulating valve are closed when the discharge temperature, which is the temperature of the refrigerant discharged from the compressor, rises to the closing threshold value.
The air conditioner according to claim 6. The control device is
After closing the first regulating valve and the second regulating valve in the heating amount up mode,
The first regulating valve and the second regulating valve are opened when the discharge temperature drops to an open threshold set to a temperature lower than the closed threshold.
The air conditioner according to claim 7. The control device is
During the dehumidifying operation in which the hot gas solenoid valve is closed,
If the suction superheat degree, which is the degree of superheat on the suction side of the compressor, is equal to or less than the first threshold value, the non-co-boiling that causes the compressor to suck by opening the first adjusting valve and the second adjusting valve. It increases 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 is
After opening the first adjusting valve and the second adjusting valve during the dehumidifying operation,
When the suction superheat degree reaches a second threshold value set to a temperature higher than the first threshold value, the first regulating valve and the second regulating valve are closed.
The air conditioner according to claim 9. The first regulating valve and the second regulating valve are solenoid valves having an open state and a closed state, respectively.
The control device is
When the first regulating valve and the second regulating valve are opened, the first regulating valve and the second regulating valve are changed from the closed state to the open state, respectively.
The air conditioner according to any one of claims 3 to 10. The first regulating valve and the second regulating valve are electronic expansion valves whose opening degrees can be adjusted, respectively.
The control device is
When the first adjusting valve and the second adjusting valve are opened, the opening degrees of the first adjusting valve and the second adjusting valve are 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 is
When the first regulating valve and the second regulating valve are opened, the frequency of the compressor is lowered.
The air conditioner according to any one of claims 3 to 12. The main circuit is such that the 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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