WO2017010007A1

WO2017010007A1 - Air conditioner

Info

Publication number: WO2017010007A1
Application number: PCT/JP2015/070441
Authority: WO
Inventors: 侑哉森下
Original assignee: 三菱電機株式会社
Priority date: 2015-07-16
Filing date: 2015-07-16
Publication date: 2017-01-19

Abstract

An air conditioner is provided with: a refrigeration cycle circuit for circulating a refrigerant through pipelines connecting a compressor, a heat-source-side heat exchanger that is divided into a plurality of regions for performing heat exchange between the refrigerant and outside air, a refrigerant flow path switching device for changing the direction in which the refrigerant flows through the heat-source-side heat exchanger divided into the plurality of regions, a decompressor, and a load-side heat exchanger; a receiver for storing the refrigerant, the receiver branching from the refrigerant pipeline between the heat-source-side heat exchanger and the load-side heat exchanger, and being provided partway along the refrigerant pipeline linked to the intake side of the compressor; a first valve branching from the refrigerant pipeline between the heat-source-side heat exchanger and the load-side heat exchanger, the first valve being provided to the refrigerant pipeline connected to the flow-in side of the receiver; a second valve connected to the flow-out side of the receiver, the second valve being provided to the refrigerant pipeline linked to the flow-in side of the compressor; and a control device for using only a part of the heat-source-side heat exchanger when the air-cooling load of the load-side heat exchanger is less than a predetermined value, and controlling the storage of refrigerant in the receiver.

Description

Air conditioner

The present invention relates to an air conditioner used for a building multi air conditioner or the like.

As an air conditioner used in a conventional multi air conditioner for buildings, for example, a receiver is provided as an excess refrigerant storage device, and the amount of refrigerant circulating in the refrigerant circuit can be adjusted according to the operating capacity of the indoor unit. The thing is known (for example, patent document 1).

International Publication No. 2012/120868

However, in the air conditioner of Patent Document 1, for example, when the cooling operation is performed in a temperature environment where the outside air is 25 ° C. or less, the amount of refrigerant circulating in the refrigerant circuit becomes excessive, and the pressure in the outdoor unit increases. . Therefore, in the air conditioner of Patent Document 1, depending on the temperature condition of the cooling operation, the compressor input increases due to an increase in the pressure in the outdoor unit, which may reduce the operating efficiency of the air conditioner.

The present invention has been made to solve the above-described problems, and provides an air conditioner capable of efficiently operating by appropriately adjusting the input of the compressor according to the temperature condition of the outside air during cooling. For the purpose.

An air conditioner according to the present invention is divided into a compressor that compresses a refrigerant, a heat source side heat exchanger that is divided into a plurality of regions that perform heat exchange between the refrigerant and outside air, and each of the plurality of regions. A refrigerant flow switching device that changes the flow direction of the refrigerant passing through the heat source side heat exchanger, a decompression device that depressurizes the refrigerant, and a load side heat exchanger that exchanges heat between the refrigerant and the indoor space. A refrigeration cycle circuit that circulates refrigerant by connecting a pipe, and is provided in the middle of the refrigerant pipe that branches from the refrigerant pipe between the heat source side heat exchanger and the load side heat exchanger and leads to the suction side of the compressor The refrigerant is stored in the refrigerant pipe between the heat source side heat exchanger and the load side heat exchanger, and is connected to the inlet side of the receiver. Connected to the first valve and the outlet side of the receiver When the cooling load of the second valve provided on the refrigerant pipe connected to the suction side of the compressor and the load side heat exchanger is smaller than a predetermined value, the heat source side divided into the plurality of regions A control device that uses only some of the heat source side heat exchangers of the heat exchanger and performs control to store the refrigerant in the receiver.

According to the present invention, since the input of the compressor is appropriately adjusted according to the temperature condition of the outside air during cooling, an efficient operation can be realized. Therefore, according to this invention, the air conditioning apparatus which can reduce energy consumption can be provided.

It is the schematic which shows the example of installation of the air conditioning apparatus 1 which concerns on Embodiment 1 of this invention. It is a schematic refrigerant circuit diagram which shows an example of the air conditioning apparatus 1 which concerns on Embodiment 1 of this invention. It is the schematic which shows simply the structure and arrangement | positioning of the receiver 60 of the air conditioning apparatus 1 which concern on Embodiment 1 of this invention. FIG. 3 is a schematic refrigerant circuit diagram illustrating an example of a refrigerant flow in the first cooling operation mode (normal cooling operation) of the air-conditioning apparatus 1 according to Embodiment 1 of the present invention. It is the schematic refrigerant circuit figure which showed the flow of the refrigerant | coolant in the 2nd air_conditionaing | cooling operation mode of the air conditioning apparatus 1 which concerns on Embodiment 1 of this invention. It is a flowchart which shows an example of the control processing in 2nd air_conditionaing | cooling operation mode in the control apparatus 90 of the air conditioning apparatus 1 which concerns on Embodiment 1 of this invention. It is a flowchart which shows an example of the control processing in the 3rd air_conditionaing | cooling operation mode in the control apparatus 90 of the air conditioning apparatus 1 which concerns on Embodiment 2 of this invention. It is the schematic refrigerant circuit figure which showed the flow of the refrigerant | coolant in the heating operation mode of the air conditioning apparatus 1 which concerns on Embodiment 3 of this invention.

Embodiment 1 FIG.
An air conditioner 1 according to Embodiment 1 of the present invention will be described. FIG. 1 is a schematic diagram illustrating an installation example of the air-conditioning apparatus 1 according to the first embodiment. In the following drawings including FIG. 1, the dimensional relationship and shape of each component may be different from the actual one. Further, in the following drawings including FIG. 1, the same or similar members or parts are denoted by the same reference numerals, or the reference numerals are omitted.

As shown in FIG. 1, the air conditioner 1 includes an outdoor unit 100 (for example, an outdoor unit that is a heat source unit), and a plurality of indoor units 200 (for example, indoor units) arranged in parallel to the outdoor unit 100. Is provided. In the air conditioning apparatus 1 according to Embodiment 1, the outdoor unit 100 and the plurality of indoor units 200 are configured as separate housings. The outdoor unit 100 and the indoor unit 200 are connected by a first communication pipe 300 and a second communication pipe 400. In addition, in the air conditioning apparatus 1 of FIG. 1, although it is set as the structure which connected the two indoor units 200, it is good also as a structure which connected the one indoor unit 200, and good also as a structure connected three or more. Further, the first connection pipe 300 and the second connection pipe 400 may be local pipes that are existing pipes.

The outdoor unit 100 (heat source side unit) is usually disposed in an outdoor space 600 (for example, the rooftop of a building 500 such as a building), and the indoor unit passes through the first communication pipe 300 or the second communication pipe 400. 200 is supplied with cold or warm heat. The indoor unit 200 (load-side unit) supplies air for cooling or heating to an indoor space 700 (for example, a living room of the building 500). For example, the indoor unit 200 is a ceiling cassette type room as shown in FIG. Can be configured as a machine. Further, as shown in FIG. 1, the outdoor unit 100 can be configured to supply warm heat to the underfloor pipe 800 in the indoor space 700 to provide floor heating for the indoor space 700.

FIG. 2 is a schematic refrigerant circuit diagram illustrating an example of the air-conditioning apparatus 1 according to the first embodiment. In FIG. 2, one outdoor unit 100 and one indoor unit 200 are connected by a first connecting pipe 300 and a second connecting pipe 400.

The air conditioner 1 of the first embodiment includes a compressor 2, an oil separator 4, a first refrigerant flow switching device 6, a second refrigerant flow switching device 7, and a heat source side heat exchanger. 8, the supercooling heat exchanger 10, the first heat source side pressure reducing device 12, the load side pressure reducing device 14, the load side heat exchanger 16, and the accumulator 18 are connected via a refrigerant pipe, A refrigeration cycle circuit for circulation is provided. Compressor 2, oil separator 4, first refrigerant flow switching device 6, second refrigerant flow switching device 7, heat source side heat exchanger 8, supercooling heat exchanger 10, first heat source side pressure reducing device 12 and the accumulator 18 are accommodated in the outdoor unit 100. The load-side decompressor 14 and the load-side heat exchanger 16 are accommodated in the indoor unit 200. The oil separator 4, the supercooling heat exchanger 10, and the accumulator 18 are not essential components and may not be provided depending on the application of the air conditioner 1. Further, FIG. 2 shows an example of mounting each unit, but each element does not necessarily have to be mounted as shown in FIG.

Compressor 2 compresses the sucked low-pressure refrigerant and discharges it as a high-pressure refrigerant. As the compressor 2, for example, a scroll compressor or a rotary compressor capable of capacity control (frequency control) by an inverter is used.

The oil separator 4 separates and removes refrigeration oil contained in the high-pressure refrigerant discharged from the compressor 2 to reduce the amount of refrigeration oil contained in the high-pressure refrigerant. The separated and removed refrigeration oil is returned to the compressor 2 via an oil return pipe (not shown).

The first refrigerant flow switching device 6 is a device configured to switch the refrigerant flow channel inside the first refrigerant flow switching device 6. The first refrigerant flow switching device 6 is controlled so as to supply cold heat from the outdoor unit 100 to the indoor unit 200 via the first communication pipe 300 during the cooling operation. In addition, the first refrigerant flow switching device 6 is controlled so as to supply heat from the outdoor unit 100 to the indoor unit 200 via the second communication pipe 400 during the heating operation.

The second refrigerant flow switching device 7 is a device configured to switch the refrigerant flow path inside the second refrigerant flow switching device 7, similarly to the first refrigerant flow switching device 6. The second refrigerant flow switching device 7 is controlled to supply cold heat from the outdoor unit 100 to the indoor unit 200 via the first communication pipe 300 during the cooling operation. In addition, the second refrigerant flow switching device 7 is controlled so as to supply heat from the outdoor unit 100 to the indoor unit 200 via the second communication pipe 400 during the heating operation.

For example, a four-way valve is used as the first refrigerant flow switching device 6 and the second refrigerant flow switching device 7. In the first embodiment, a terminal member 7a for blocking the refrigerant flow path is connected to one end of the refrigerant flow path inside the second refrigerant flow switching device 7. The “cooling operation” is an operation for supplying a low-temperature and low-pressure refrigerant to the load-side heat exchanger 16, and an operation for supplying air for cooling to the indoor space 700 in FIG. The “heating operation” is an operation for supplying a high-temperature and high-pressure refrigerant to the load-side heat exchanger 16, and an operation for supplying heating air to the indoor space 700 of FIG. Further, as the first refrigerant flow switching device 6 and the second refrigerant flow switching device 7, a two-way valve or a three-way valve may be used.

The heat source side heat exchanger 8 is a heat exchanger that functions as a radiator (condenser) during cooling operation and functions as an evaporator (cooler) during heating operation. The heat source side heat exchanger 8 includes a refrigerant flowing inside the heat source side heat exchanger 8 and outside air (for example, outdoor air in the outdoor space 600 of FIG. 1) blown by a heat source side fan (not shown). It is configured to perform heat exchange. As the heat source side heat exchanger 8, for example, a cross fin type fin-and-tube heat exchanger composed of a heat transfer tube and a plurality of fins is used.

2, the heat source side heat exchanger 8 is divided into two heat exchange regions, region A and region B. One end of a heat transfer tube (not shown) in the region A of the heat source side heat exchanger 8 is connected to a plurality of first header branch tubes 82 branched from the first header main tube 81. The other end of the heat transfer tube in the region A of the heat source side heat exchanger 8 is connected to a plurality of second header branch tubes 83 branched from the second header main tube 84. In FIG. 2, the heat source side heat exchanger 8 is configured to be divided into two heat exchange regions, region A and region B, but may be configured to be divided into three or more heat exchange regions. .

On the other hand, one end of a heat transfer tube (not shown) of the heat source side heat exchanger 8 in the region B is connected to a plurality of third header branch tubes 86 branched from the third header main tube 85. . The other end portion of the heat transfer pipe of the heat source side heat exchanger 8 in the region B is connected to a plurality of fourth header branch pipes 87 branched from the fourth header main pipe 88.

The supercooling heat exchanger 10 is a heat exchanger that further cools the high-pressure refrigerant flowing from the heat source side heat exchanger 8 during the cooling operation. The supercooling heat exchanger 10 is, for example, a double-tube heat exchanger having an inner pipe (not shown) and an outer pipe (not shown) arranged concentrically when viewed from the end of the inner pipe. It is possible to perform heat exchange between the high-pressure refrigerant flowing in the inner pipe and the decompressed refrigerant flowing in the outer pipe. When the supercooling heat exchanger 10 is a double-pipe heat exchanger, during the heating operation, the supercooling heat exchanger 10 functions as a part of the refrigerant pipe constituting the refrigeration cycle circuit. A specific configuration of the refrigerant circuit when the supercooling heat exchanger 10 is a double-pipe heat exchanger will be described later. In addition, you may comprise the supercooling heat exchanger 10 with a plate type heat exchanger.

The first heat source side decompression device 12 expands and decompresses the high-pressure refrigerant during the cooling operation, and flows into the first communication pipe 300 as a refrigerant having a pressure lower than the design pressure of the first communication pipe 300. It functions as a (squeezing device for liquid equalization between outdoor units). For example, when the first connecting pipe 300 is an existing pipe, the design pressure of the first connecting pipe 300 is set to the pressure resistance reference value of the first connecting pipe 300. Further, the first heat source side decompression device 12 functions as a throttle device that expands and decompresses the refrigerant flowing from the first communication pipe 300 and flows into the heat source side heat exchanger 8 during the heating operation. As the first heat source side pressure reducing device 12, an electronic expansion valve such as a linear electronic expansion valve (LEV) whose opening degree can be adjusted in multiple stages or continuously is used.

During the cooling operation, the load side decompression device 14 further expands and decompresses the refrigerant having a pressure lower than the design pressure of the first communication pipe 300 flowing from the first communication pipe 300 and flows into the load side heat exchanger 16. It functions as an expansion device (indoor expansion device). Further, the load-side decompression device 14 is a throttling device that expands and decompresses the high-pressure refrigerant during the heating operation, and flows into the first communication pipe 300 as a refrigerant having a pressure lower than the design pressure of the first communication pipe 300. Function. The load side pressure reducing device 14 is configured as an electronic expansion valve such as a linear electronic expansion valve whose opening degree can be adjusted in multiple stages or continuously.

The load side heat exchanger 16 (use side heat exchanger) is a heat exchanger that functions as an evaporator (cooler) during cooling operation and as a radiator (condenser) during heating operation. The load-side heat exchanger 16 is configured to exchange heat between, for example, a refrigerant flowing inside the load-side heat exchanger 16 and outside air (for example, indoor air in the indoor space 700 in FIG. 1). As the load side heat exchanger 16, for example, a cross fin type fin-and-tube heat exchanger composed of a heat transfer tube and a plurality of fins is used. Moreover, the load side heat exchanger 16 can be comprised so that external air may be supplied by the ventilation from a load side ventilation fan (not shown).

The accumulator 18 is a storage container having a refrigerant storage function for storing excess refrigerant generated due to a difference in refrigerant amount during heating operation and cooling operation. Further, the accumulator 18 retains the liquid refrigerant that is temporarily generated when the operation state of the air conditioner 1 is changed, such as a transient operation change, so that a large amount of liquid refrigerant flows into the compressor 2. It is also a storage container having a gas-liquid separation function to prevent this.

Next, the refrigerant piping of the outdoor unit 100 in the air conditioner 1 of Embodiment 1 will be described.

In the outdoor unit 100, a discharge pipe (not shown) of the compressor 2 and the inlet of the oil separator 4 are connected by a first heat source side refrigerant pipe 21. The refrigerant outlet of the oil separator 4 and the first refrigerant flow switching device 6 are connected by a second heat source side refrigerant pipe 22. A check valve 41 is disposed in the second heat source side refrigerant pipe 22 to prevent the high-pressure refrigerant from flowing back to the compressor 2. Between the branch part 22a of the 2nd heat source side refrigerant | coolant piping 22 located between the non-return valve 41 and the 1st refrigerant | coolant flow path switching apparatus 6, and the 2nd refrigerant | coolant flow path switching apparatus 7, it is 5th. The heat source side refrigerant pipe 25 is branched and connected.

The first refrigerant flow switching device 6 and the first header main pipe 81 are connected by a third heat source side refrigerant pipe 23. The second refrigerant flow switching device 7 and the third header main pipe 85 are connected by a sixth heat source side refrigerant pipe 26. One end of the fourth heat source side refrigerant pipe 24 is connected to the second header main pipe 84. One end of the seventh heat source side refrigerant pipe 27 is connected to the fourth header main pipe 88. The other one end of the fourth heat source side refrigerant pipe 24 and the seventh heat source side refrigerant pipe 27 joins the fourth heat source side refrigerant pipe 24 and the seventh heat source side refrigerant pipe 27 during the cooling operation. It is connected to a connecting member 43 that functions as a merger. The connecting member 43 is a member that functions as a distributor for diverting the refrigerant to the fourth heat source side refrigerant pipe 24 and the seventh heat source side refrigerant pipe 27 during the heating operation.

The connecting member 43 and the supercooling heat exchanger 10 are connected by an eighth heat source side refrigerant pipe 28. The subcooling heat exchanger 10 and the first communication pipe 300 are connected by a ninth heat source side refrigerant pipe 29. The first heat source side decompression device 12 is disposed in the ninth heat source side refrigerant pipe 29. In addition, a first heat source side connection valve 47a is disposed at the end of the ninth heat source side refrigerant pipe 29 on the first communication pipe 300 side, and the first heat source side connection valve 47a has a first end. A first joint portion 49a such as a flare joint is attached to the connecting pipe 300 side. The ninth heat source side refrigerant pipe 29 is connected to the first communication pipe 300 at the first joint portion 49a. The first heat source side connection valve 47a is constituted by, for example, a two-way valve such as a two-way electromagnetic valve that can be switched between open and closed. Further, in the ninth heat source side refrigerant pipe 29, a position between the first heat source side pressure reducing device 12 and the first heat source side connection valve 47a is used to scavenge dust, impurities, etc. contained in the refrigerant. The 1st strainer 45a which is a filter is arrange | positioned.

The first refrigerant flow switching device 6 and the second communication pipe 400 are connected by a tenth heat source side refrigerant pipe 30. A second heat source side connection valve 47b is disposed at the end of the tenth heat source side refrigerant pipe 30 on the second communication pipe 400 side, and the second connection pipe of the second heat source side connection valve 47b. On the 400 side, a second joint portion 49b such as a flare joint is attached. The 10th heat source side refrigerant | coolant piping 30 is connected with the 2nd connection piping 400 by the 2nd coupling part 49b. The second heat source side connection valve 47b is configured by, for example, a two-way valve such as a two-way electromagnetic valve that can be switched between open and closed. In addition, in the tenth heat source side refrigerant pipe 30, a position between the first refrigerant flow switching device 6 and the second heat source side connection valve 47b removes dust, impurities, and the like contained in the refrigerant. The 2nd strainer 45b which is a filter of this is arrange | positioned.

The first refrigerant flow switching device 6 and the first branch portion 32a of the twelfth heat source side refrigerant pipe 32 are connected by an eleventh heat source side refrigerant pipe 31. The twelfth heat source side refrigerant pipe 32 is a refrigerant pipe that connects the second refrigerant flow switching device 7 and the inlet of the accumulator 18. The inlet of the accumulator 18 and the suction pipe (not shown) of the compressor 2 are connected by a thirteenth heat source side refrigerant pipe 33.

Next, the refrigerant piping of the indoor unit 200 in the air conditioner 1 of the first embodiment will be described.

The first communication pipe 300 and the load side heat exchanger 16 are connected by a first load side refrigerant pipe 35. The load side decompression device 14 is disposed in the first load side refrigerant pipe 35. Further, a joint portion (not shown) such as a flare joint is provided on the first communication pipe 300 side of the first load-side refrigerant pipe 35, and is connected to the first communication pipe 300 at the joint portion. Has been.

The load side heat exchanger 16 and the second communication pipe 400 are connected by a second load side refrigerant pipe 36. A joint portion (not shown) such as a flare joint is provided on the second load-side refrigerant pipe 36 on the second communication pipe 400 side, and is connected to the second communication pipe 400 at the joint. Yes.

In the air-conditioning apparatus 1 according to the first embodiment, any kind of refrigerant can be selected as the refrigerant that circulates through the refrigerant pipe described above depending on the application of the air-conditioning apparatus 1. As the refrigerant to be circulated in the refrigeration cycle circuit, for example, a single refrigerant such as R22, R134a, R32, HFO1234yf, HFO1234ze, or HFO1123, a pseudo-azeotropic refrigerant mixture such as R410A or R404A, a non-azeotropic refrigerant mixture such as R407C, Alternatively, a refrigerant with a low global warming potential such as CF ₃ CF═CH ₂ containing a double bond in the chemical formula can be used. The above-mentioned refrigerant may be used as a mixture in which two or more kinds are mixed. As the refrigerant circulates in the refrigeration cycle, it is possible to use natural refrigerant such as CO ₂ or propane.

Next, a specific configuration of the refrigerant circuit of the supercooling heat exchanger 10 housed in the outdoor unit 100 in the air conditioner 1 of Embodiment 1 will be described.

As described above, the supercooling heat exchanger 10 can be configured as a double-pipe heat exchanger. As described above, the double-tube supercooling heat exchanger 10 has an inner tube (not shown) and an outer tube (not shown) arranged concentrically when viewed from the end of the inner tube. The heat exchange is performed between the high-pressure refrigerant flowing in the inner pipe and the decompressed refrigerant flowing in the outer pipe.

As for the 8th heat source side refrigerant | coolant piping 28 by which one edge part was connected to the connection member 43, the other one edge part is connected with one edge part of the inner tube | pipe of the supercooling heat exchanger 10. FIG. The ninth heat source side refrigerant pipe 29 whose one end is connected to the first connecting pipe 300 has the other end connected to the other end of the inner pipe of the supercooling heat exchanger 10. Has been. The branch portion 29a of the ninth heat source side refrigerant pipe 29 located between the supercooling heat exchanger 10 and the first heat source side decompression device 12, and the ninth heat source of the outer pipe of the supercooling heat exchanger 10 A first heat source side branch refrigerant pipe 51 is connected to the end on the side refrigerant pipe 29 side. One end of the second heat source side branch refrigerant pipe 53 is connected to the end of the outer pipe of the supercooling heat exchanger 10 on the side of the eighth heat source side refrigerant pipe 28. The other end of the second heat source side branch refrigerant pipe 53 is connected to the second branch part 32 b of the twelfth heat source side refrigerant pipe 32 connected to the inlet of the accumulator 18.

The second heat source side decompression device 13 is disposed in the first heat source side branch refrigerant pipe 51. The second heat source-side decompression device 13 expands and decompresses the high-pressure refrigerant that flows from the branch portion 29a of the ninth heat source-side refrigerant pipe 29 to the first heat source-side branch refrigerant pipe 51 during cooling operation. Thus, it functions as a throttle device (heat source side throttle device) that causes the decompressed refrigerant to flow into the outer tube of the supercooling heat exchanger 10. The second heat source side pressure reducing device 13 is configured as an electronic expansion valve such as a linear electronic expansion valve (LEV) whose opening degree can be adjusted in multiple stages or continuously.

Next, in the outdoor unit 100 of the air-conditioning apparatus 1 according to Embodiment 1, the configuration of the bypass refrigerant circuit provided between the seventh heat source side refrigerant pipe 27 and the second heat source side branch refrigerant pipe 53 is described. explain.

As described above, the seventh heat source side refrigerant pipe 27 is a refrigerant pipe connected between the fourth header main pipe 88 and the connecting member 43. The fourth header main pipe 88 is a refrigerant pipe connected to a heat transfer pipe (not shown) of the heat source side heat exchanger 8 in the region B via a plurality of fourth header branch pipes 87.

Further, as described above, one end of the second heat source side branch refrigerant pipe 53 is connected to the refrigerant outlet side end of the outer tube of the supercooling heat exchanger 10 and the other one end is the twelfth. It is the refrigerant | coolant piping connected to the 2nd branch part 32b of the heat source side refrigerant | coolant piping 32 of this. The twelfth heat source side refrigerant pipe 32 is a refrigerant pipe connected to the inflow port of the accumulator 18.

A flow path switching valve 55 is disposed in the seventh heat source side refrigerant pipe 27. The flow path switching valve 55 and the branch portion 53 a of the second heat source side branch refrigerant pipe 53 are connected by a third heat source side branch refrigerant pipe 57. The flow path switching valve 55 switches the refrigerant flow path inside the flow path switching valve 55 during the cooling operation, and connects the connection destination of the seventh heat source side refrigerant pipe 27 on the fourth header main pipe 88 side to the connecting member 43. The second heat source side refrigerant pipe 27 or the second heat source side branch refrigerant pipe 53 is switched to two directions. The flow path switching valve 55 is configured to connect the seventh heat source side refrigerant pipe 27 on the connecting member 43 side and the seventh heat source side refrigerant pipe 27 on the fourth header main pipe 88 side during the heating operation. Is done. For example, a three-way valve is used as the flow path switching valve 55.

Next, the configuration of the receiver 60 (liquid receiver) disposed in the outdoor unit 100 of the air-conditioning apparatus 1 according to Embodiment 1 will be described with reference to FIGS.

FIG. 3 is a schematic diagram schematically showing the configuration and arrangement of the receiver 60 of the air-conditioning apparatus 1 according to Embodiment 1. In FIG. 3, the flow direction of the refrigerant is indicated by white block arrows.

The receiver 60 includes a storage 60a that is a casing that stores liquid refrigerant, an inflow pipe 60b that is a refrigerant pipe that flows the refrigerant into the storage 60a, an outflow pipe 60c that is a refrigerant pipe that causes the refrigerant to flow out of the storage 60a, and a storage And a leg portion 60d which is a support member for supporting the bottom portion of 60a. The receiver 60 is configured as a vertical-type surplus liquid refrigerant storage container.

As shown in FIG. 3, the branch portion 28 a of the eighth heat source side refrigerant pipe 28 and the end portion on the inlet side of the inflow pipe 60 b of the receiver 60 are connected by a fourth heat source side branch refrigerant pipe 61. Yes. As shown in FIG. 3, the fifth heat source side branch is provided between the end portion on the outlet side of the outlet pipe 60 c of the receiver 60 and the third branch portion 32 c of the twelfth heat source side refrigerant pipe 32. The refrigerant pipe 65 connects. As described above, the eighth heat source side refrigerant pipe 28 is a refrigerant pipe connecting the connecting member 43 and the inner pipe of the supercooling heat exchanger 10, and the twelfth heat source side refrigerant pipe 32 is the accumulator 18. It is refrigerant piping connected to the inflow port.

As shown in FIG. 3, the branching portion 28 a of the eighth heat source side refrigerant pipe 28 is arranged so as to be located above the end of the inlet of the inflow pipe 60 b of the receiver 60. The fourth heat source side branch refrigerant pipe 61 is connected to the branch portion 28 a of the eighth heat source side refrigerant pipe 28 so as to be positioned below the eighth heat source side refrigerant pipe 28. Moreover, the inflow pipe 60b of the receiver 60 is arrange | positioned at the top part of the storage 60a, and the edge part by the side of the outflow port of the inflow pipe 60b is connected with the internal space of the storage 60a. Therefore, in the receiver 60 according to the first embodiment, the liquid refrigerant flowing into the fourth heat source side branch refrigerant pipe 61 from the branch portion 28a of the eighth heat source side refrigerant pipe 28 flows into the receiver 60 by its own weight. The pipe 60b is surely introduced and stored in the storage 60a.

In the first embodiment, the outflow pipe 60c of the receiver 60 is disposed at the bottom of the storage 60a, and the end of the outflow pipe 60c on the inlet side communicates with the internal space below the storage 60a. Therefore, the receiver 60 according to the first embodiment can cause the liquid refrigerant stored at the bottom of the storage 60a to flow into the fifth heat source side branch refrigerant pipe 65 from the outflow pipe 60c.

In the fourth heat source side branch refrigerant pipe 61, an electromagnetic valve 63 is arranged. The solenoid valve 63 is a valve on the refrigerant inflow side to the receiver 60 that opens or closes the refrigerant flow path of the fourth heat source side branched refrigerant pipe 61 by supplying power or stopping power. In the first embodiment, instead of the electromagnetic valve 63, an electronic expansion valve such as a linear electronic expansion valve (LEV) whose opening degree can be adjusted in multiple steps or continuously may be used.

A flow rate adjustment valve 67 is arranged in the fifth heat source side branch refrigerant pipe 65. The flow rate adjusting valve 67 is a valve that adjusts the amount of refrigerant returned to the refrigeration cycle circuit by storing the refrigerant in the accumulator 18 through the fifth heat source side branched refrigerant pipe 65. As the flow rate adjusting valve 67, for example, an electronic expansion valve such as a linear electronic expansion valve (LEV) whose opening degree can be adjusted in multiple stages or continuously is used.

In FIG. 3, in order to clarify the arrangement of the eighth heat source side refrigerant pipe 28, the fourth heat source side refrigerant pipe 24, the seventh heat source side refrigerant pipe 27, the connecting member 43, and the second header are shown. Although the branch pipe 83 and the second header main pipe 84 are shown in the drawing, the description thereof is omitted because these components have already been described. FIG. 3 shows a second temperature sensor 74 that is a liquid refrigerant temperature detection sensor. The second temperature sensor 74 will be described later.

Next, the sensor arranged in the air conditioner 1 according to the first embodiment will be described with reference to FIG.

The air conditioner 1 according to Embodiment 1 includes a first pressure sensor 70, a second pressure sensor 71, a first temperature sensor 73, a second temperature sensor 74, and a third temperature sensor. 75, a fourth temperature sensor 76, and a refrigerant leakage detection sensor 78.

The first pressure sensor 70 is disposed in the second heat source side refrigerant pipe 22. The first pressure sensor 70 is a high-pressure sensor that detects the pressure of the high-temperature and high-pressure refrigerant that flows into the second heat source side refrigerant pipe 22 from the discharge pipe of the compressor 2 via the oil separator 4.

The second pressure sensor 71 is disposed in the twelfth heat source side refrigerant pipe 32. The second pressure sensor 71 is a low-pressure sensor that detects the pressure of the low-pressure refrigerant flowing into the suction port of the compressor 2 from the twelfth heat source side refrigerant pipe 32 via the accumulator 18.

As the first pressure sensor 70 and the second pressure sensor 71, a crystal piezoelectric pressure sensor, a semiconductor sensor, a pressure transducer, or the like is used. The first pressure sensor 70 and the second pressure sensor 71 may be the same type or different types.

The first temperature sensor 73 is disposed, for example, on the upstream side of a heat source side fan (not shown), and is sucked by the heat source side fan and is sent to the heat source side heat exchanger 8 (for example, outside air shown in FIG. 1). This is an outdoor temperature sensor that detects the temperature of the outdoor air in the outdoor space 600.

The second temperature sensor 74 is disposed in the eighth heat source side refrigerant pipe 28. The second temperature sensor 74 detects the temperature of the liquid refrigerant flowing from the heat source side heat exchanger 8 into the eighth heat source side refrigerant pipe 28 via the eighth heat source side refrigerant pipe 28 during the cooling operation. It is a temperature sensor (liquid refrigerant temperature detection sensor). The second temperature sensor 74 is a temperature sensor that detects the temperature of the two-phase refrigerant decompressed by the first heat source side decompression device 12 via the eighth heat source side refrigerant pipe 28 during the heating operation. is there.

The third temperature sensor 75 is disposed in the first load side refrigerant pipe 35. The third temperature sensor 75 is a temperature sensor (use side heat exchanger) that detects the temperature of the two-phase refrigerant decompressed by the load side decompression device 14 via the first load side refrigerant pipe 35 during the cooling operation. Liquid side sensor). Further, the third temperature sensor 75 detects the temperature of the liquid refrigerant flowing from the load-side heat exchanger 16 to the first load-side refrigerant pipe 35 via the first load-side refrigerant pipe 35 during the heating operation. It is a temperature sensor.

The fourth temperature sensor 76 is disposed in the second load side refrigerant pipe 36. The third temperature sensor 75 detects the temperature of the low-pressure refrigerant flowing from the load-side heat exchanger 16 to the second load-side refrigerant pipe 36 through the second load-side refrigerant pipe 36 during the cooling operation. Sensor (use side heat exchanger gas side sensor). Further, the fourth temperature sensor 76 determines the temperature of the high-temperature and high-pressure refrigerant flowing into the second load-side refrigerant pipe 36 from the discharge pipe of the compressor 2 through the oil separator 4 during the heating operation. It is a temperature sensor detected via the load side refrigerant | coolant piping 36.

Examples of materials for the first temperature sensor 73, the second temperature sensor 74, the third temperature sensor 75, and the fourth temperature sensor 76 include a semiconductor (for example, a thermistor) or a metal (for example, a resistance temperature detector). Is used. The first temperature sensor 73, the second temperature sensor 74, the third temperature sensor 75, and the fourth temperature sensor 76 may be made of the same material or different materials. Good.

The refrigerant leakage detection sensor 78 is disposed in the indoor unit 200 and detects refrigerant leakage from the indoor unit 200. The refrigerant leakage detection sensor 78 is disposed in the indoor space 700 of FIG. 1 in order to prevent, for example, refrigerant leakage into the indoor space 700 of FIG. 1 (for example, the living room of the building 500). As the refrigerant leakage detection sensor 78, for example, a gas sensor such as a semiconductor gas sensor or a hot wire semiconductor gas sensor is used.

Two or more refrigerant leakage detection sensors 78 may be arranged in the indoor space 700 in order to prevent refrigerant leakage into the indoor space 700. Further, for example, in a portion where the refrigerant leakage inside the indoor unit 200 is likely to occur, such as a connection portion between the first load side refrigerant pipe 35 or the second load side refrigerant pipe 36 and the load side heat exchanger 16. You may arrange.

Next, the control device 90 of the air-conditioning apparatus 1 according to Embodiment 1 will be described with reference to FIG.

The control device 90 according to the first embodiment controls the operation of the entire air conditioner 1 including driving or stopping of the outdoor unit 100. Further, as shown in FIG. 2, the control device 90 is also connected to an indoor unit control device 95 (indoor control device) that controls the operation of the indoor unit 200 via a transmission line 98. It is comprised so that it can communicate. In addition, you may comprise so that communication between the control apparatus 90 and the indoor unit control apparatus 95 can be performed by radio | wireless.

The control device 90 and the indoor unit control device 95 have a microcomputer having a CPU that functions as a calculation unit, a memory (for example, ROM, RAM, etc.) that functions as a storage unit, an I / O port that functions as a communication unit, and the like. is doing.

The indoor unit controller 95 receives the electrical signal of the temperature information in the indoor unit 200 detected by the third temperature sensor 75 and the fourth temperature sensor 76 or the electrical signal of the refrigerant leak detected by the refrigerant leak detection sensor 78. , And configured to transmit to the control device 90 via the transmission line 98. Further, the indoor unit control device 95 is configured to transmit information related to the operating state of the indoor unit 200 to the control device 90 via the transmission line 98. The information related to the operating state of the indoor unit 200 includes information on driving or stopping of the indoor unit 200, power consumption of the indoor unit 200, information on the operating capacity of the indoor unit 200, information on switching between cooling operation and heating operation, etc. It is included.

The control device 90 receives the electrical signal of the pressure information detected by the first pressure sensor 70 and the second pressure sensor 71 and the electrical signal of the temperature information detected by the first temperature sensor 73 and the second temperature sensor 74. Configured to receive. In addition, the control device 90 is configured to receive temperature information or an electric signal of refrigerant leakage transmitted from the indoor unit control device 95 via the transmission line 98 and information related to the operating state of the indoor unit 200. The control device 90 controls operations of various actuators of the air conditioning device 1 based on the received information. The various actuators of the air conditioner 1 include, for example, the compressor 2, the first refrigerant flow switching device 6, the second refrigerant flow switching device 7, the first heat source side pressure reducing device 12, and the second heat source side. The pressure reducing device 13, the load side pressure reducing device 14, the flow path switching valve 55, the electromagnetic valve 63, and the flow rate adjusting valve 67 are included.

The control device 90 and the first pressure sensor 70, the second pressure sensor 71, the first temperature sensor 73, and the second temperature sensor 74 are connected by a communication line (not shown). Can be configured. Similarly, the indoor unit control device 95, the third temperature sensor 75, the fourth temperature sensor 76, and the refrigerant leakage detection sensor 78 can be connected by a communication line (not shown). In addition to the memory such as ROM and RAM, the control device 90 may be configured to have a storage unit (not shown) that can store various data such as a standard outside air temperature range.

Next, the operation of the refrigeration cycle circuit during normal cooling operation of the air-conditioning apparatus 1 according to Embodiment 1 will be described.

“Normal cooling operation” means, for example, a cooling operation under the cooling condition defined in the JIS standard (JIS B 8616) of the package air conditioner. In the subsequent embodiments including the first embodiment, the “normal cooling operation” is referred to as a first cooling operation mode. In the first cooling operation mode, the outside air temperature is in the standard temperature range, the indoor unit 200 is in the standard operation capacity range, and the air is discharged from the compressor 2 detected by the first pressure sensor 70. This refers to a cooling operation performed by the air-conditioning apparatus 1 according to Embodiment 1 when the pressure of the high-temperature and high-pressure gas refrigerant is within the range of the standard high-pressure.

In the following embodiments including the first embodiment, the standard temperature range of the outside air temperature is, for example, a temperature range of 25 ° C. to 43 ° C. The lower limit value of the standard operating capacity range is, for example, 50% operating capacity when the total operating capacity of the indoor unit 200 in the air conditioner 1 is 100%. In addition, the upper limit value of the standard high pressure range is, for example, 36 kg / cm ² .

FIG. 4 is a schematic refrigerant circuit diagram showing a refrigerant flow in the first cooling operation mode (normal cooling operation) of the air-conditioning apparatus 1 according to Embodiment 1. In FIG. 4, the flow direction of the refrigerant is indicated by solid line arrows.

The high-temperature and high-pressure gas refrigerant discharged from the compressor 2 flows into the oil separator 4 via the first heat source side refrigerant pipe 21. In the oil separator 4, the components of the refrigerating machine oil are separated and removed from the high-temperature and high-pressure gas refrigerant discharged from the compressor 2. A part of the high-temperature and high-pressure gas refrigerant from which the components of the refrigerating machine oil are separated and removed by the oil separator 4 includes the second heat source side refrigerant pipe 22, the first refrigerant flow switching device 6, and the third heat source side refrigerant pipe. 23, the first header main pipe 81, and the plurality of first header branch pipes 82 flow into the region A of the heat source side heat exchanger 8. The remaining portion of the high-temperature and high-pressure gas refrigerant from which the components of the refrigeration oil are separated and removed by the oil separator 4 is the second heat source side refrigerant pipe 22, the fifth heat source side refrigerant pipe 25, and the second refrigerant flow. It flows into the region B of the heat source side heat exchanger 8 via the path switching device 7, the sixth heat source side refrigerant pipe 26, the third header main pipe 85, and the plurality of third header branch pipes 86. . The high-temperature and high-pressure gas refrigerant that has flowed into the heat source side heat exchanger 8 is heat-exchanged by releasing heat to a low-temperature medium such as outdoor air in the outdoor space 600 in FIG. 1, and the high-temperature and high-pressure gas refrigerant is condensed and liquefied. And high pressure liquid refrigerant.

The high-pressure liquid refrigerant condensed and liquefied in the region A of the heat source side heat exchanger 8 passes through the plurality of second header branch pipes 83 and the second header main pipe 84 to form a fourth heat source side refrigerant pipe. 24. In addition, the high-pressure liquid refrigerant condensed and liquefied in the region B of the heat source side heat exchanger 8 passes through the fourth header branch pipe 87 and the fourth header main pipe 88 to the seventh heat source side. It flows into the refrigerant pipe 27. The high-pressure liquid refrigerant flowing through the fourth heat source side refrigerant pipe 24 and the seventh heat source side refrigerant pipe 27 is joined by the connecting member 43 and flows into the eighth heat source side refrigerant pipe 28.

The high-pressure liquid refrigerant flowing through the eighth heat source side refrigerant pipe 28 flows into the inner pipe of the supercooling heat exchanger 10 and is heat-exchanged with the refrigerant flowing through the outer pipe of the supercooling heat exchanger 10 to be supercooled. The high-pressure liquid refrigerant becomes a supercooled high-pressure liquid refrigerant and flows into the ninth heat source side refrigerant pipe 29. In the air conditioner 1 of the first embodiment, the refrigerant flowing through the outer pipe of the supercooling heat exchanger 10 is divided by the branch portion 29a of the ninth heat source side refrigerant pipe 29, and the first heat source side branched refrigerant. The liquid refrigerant or the two-phase refrigerant flows into the pipe 51 and is expanded and depressurized by the second heat source side decompression device 13 (for example, medium pressure). The liquid refrigerant or the two-phase refrigerant that has been expanded and depressurized by the second heat source side pressure reducing device 13 (for example, medium pressure) is connected to the inner pipe of the supercooling heat exchanger 10 by the outer pipe of the supercooling heat exchanger 10. Heat exchange with the flowing high-pressure liquid refrigerant results in a high-temperature gas refrigerant or a two-phase refrigerant with high dryness. The high-temperature gas refrigerant or the two-phase refrigerant having a high dryness flowing from the outer pipe of the supercooling heat exchanger 10 into the second heat source side branch refrigerant pipe 53 passes through the twelfth heat source side refrigerant pipe 32 to be an accumulator. 18 is injected.

The high-pressure liquid refrigerant that was supercooled by the supercooling heat exchanger 10 and flowed into the ninth heat source side refrigerant pipe 29 was expanded and depressurized by the first heat source side decompression device 12 to be depressurized (for example, (Pressure) liquid refrigerant or two-phase refrigerant. The decompressed liquid refrigerant or two-phase refrigerant flows out of the outdoor unit 100 and flows into the indoor unit 200 via the first connection pipe 300.

The liquid refrigerant or the two-phase refrigerant that has flowed into the indoor unit 200 flows into the load-side decompression device 14 via the first load-side refrigerant pipe 35. The liquid refrigerant or two-phase refrigerant that has flowed into the load-side decompression device 14 is further expanded and decompressed by the load-side decompression device 14 to become a low-temperature and low-pressure two-phase refrigerant. The low-temperature and low-pressure two-phase refrigerant flows into the load-side heat exchanger 16 and is heat-exchanged by absorbing heat from a high-temperature medium such as indoor air in the indoor space 700 of FIG. The gas is evaporated and becomes a two-phase refrigerant or gas refrigerant having a low temperature and low pressure and high dryness, and flows into the second load side refrigerant pipe 36. The low-temperature and low-pressure two-phase refrigerant or low-temperature and low-pressure gas refrigerant that has flowed into the second load-side refrigerant pipe 36 flows out of the indoor unit 200 and passes through the second connecting pipe 400 to the outdoor unit. 100 flows in. The low-temperature and low-pressure two-phase refrigerant or gas refrigerant flowing into the outdoor unit 100 includes a tenth heat source side refrigerant pipe 30, a first refrigerant flow switching device 6, an eleventh heat source side refrigerant pipe 31, and It is injected into the accumulator 18 via the twelfth heat source side refrigerant pipe 32. In the accumulator 18, the liquid phase component of the refrigerant injected from the twelfth heat source side refrigerant pipe 32 is separated and stored, and the low-temperature and low-pressure gas refrigerant flows into the thirteenth heat source side refrigerant pipe 33 from the accumulator 18, and the compressor 2 is inhaled. The refrigerant sucked into the compressor 2 is compressed to become a high-temperature and high-pressure gas refrigerant and is discharged from the compressor 2. In the cooling operation of the air conditioner 1, the above cycle is repeated.

Next, control processing of the control device 90 of the air-conditioning apparatus 1 according to Embodiment 1 in the first cooling operation mode will be described.

The control device 90 causes the refrigerant to flow through the refrigerant flow path inside the first refrigerant flow switching device 6 from the second heat source side refrigerant pipe 22 to the third heat source side refrigerant pipe 23, and the tenth heat source side refrigerant. The pipe 30 communicates with the eleventh heat source side refrigerant pipe 31 so that the refrigerant flows. In addition, the control device 90 causes the refrigerant flow path inside the second refrigerant flow switching device 7 to communicate so that the refrigerant flows from the fifth heat source side refrigerant pipe 25 to the sixth heat source side refrigerant pipe 26. In addition, the control device 90 causes the refrigerant flow path inside the second refrigerant flow switching device 7 to which the termination member 7a is connected to communicate with the twelfth heat source side refrigerant pipe 32, and the twelfth heat source side refrigerant pipe 32. The refrigerant is prevented from flowing backward in the direction opposite to the inlet direction of the accumulator 18. Further, the controller 90 connects the refrigerant flow path of the flow path switching valve 55 provided in the seventh heat source side refrigerant pipe 27 from the seventh heat source side refrigerant pipe 27 on the fourth header main pipe 88 side. The refrigerant is communicated with the seventh heat source side refrigerant pipe 27 on the 43 side so that the refrigerant flows.

Further, the control device 90 performs control to close the electromagnetic valve 63 and block the flow of high-pressure liquid refrigerant from the fourth heat source side branch refrigerant pipe 61 to the receiver 60. Further, the control device 90 opens the flow rate adjustment valve 67 to a predetermined opening degree (for example, when the fully open state opening degree of the flow rate adjustment valve 67 is 1 and the opening degree of the closed state is 0, the opening degree is about 1/8. And the refrigerant stored in the storage 60 a of the receiver 60 passes through the fifth heat source side branch refrigerant pipe 65 and the twelfth heat source side refrigerant pipe 32 due to the pressure difference generated by the flow rate adjustment valve 67. , Control to flow to the accumulator 18.

As described above, when the air-conditioning apparatus 1 is driven in the first cooling operation mode, the cooling load is high and the amount of refrigerant used in the refrigeration cycle circuit is increased. Control is performed to return the refrigerant stored in the receiver 60 to the refrigeration cycle circuit.

The control device 90 calculates the saturation temperature (evaporation temperature) in the load-side heat exchanger 16 from the refrigerant suction pressure detected by the second pressure sensor 71. The control device 90 subtracts the refrigerant temperature detected by the fourth temperature sensor 76 from the calculated evaporation temperature, calculates the degree of superheat in the refrigeration cycle circuit of the air conditioner 1, and the degree of superheat is a predetermined temperature range (for example, 5 ° C.), the opening degree of the load side decompression device 14 is controlled. Further, the control device 90 controls the operation frequency of the compressor 2 so that the evaporation temperature becomes the target temperature. The target value of the evaporation temperature may be a fixed value (for example, −30 ° C.), or an indoor temperature sensor (not shown) is arranged in the indoor space 700 of FIG. 1, and the temperature detected by the indoor temperature sensor and the user The control device 90 may be configured to change the target temperature by calculating the maximum value of the set temperature difference set by the control device 90.

Next, the operation of the refrigeration cycle circuit in the second cooling operation mode (the cooling operation mode under the cooling intermediate load condition) of the air-conditioning apparatus 1 according to Embodiment 1 will be described. The “second cooling operation mode” means that the outside air temperature is less than the lower limit (for example, less than 25 ° C.) of the standard temperature range of the outside air temperature in the first cooling operation mode, and the indoor unit In the case where 200 operating capacity is less than the lower limit value of the standard operating capacity range (for example, operating capacity less than 50% of the total operating capacity) (in the cooling intermediate load condition), the first embodiment is used. The cooling operation performed with the air conditioning apparatus 1 which concerns is said.

FIG. 5 is a schematic refrigerant circuit diagram showing a refrigerant flow in the second cooling operation mode of the air-conditioning apparatus 1 according to Embodiment 1. In FIG. 5, the flow direction of the refrigerant is indicated by solid arrows.

In the second cooling operation mode, the air conditioner 1 is discharged from the compressor 2, passes through the oil separator 4, and the high-temperature high-pressure gas refrigerant flowing into the second heat source side refrigerant pipe 22 is the first Only the region A of the heat source side heat exchanger 8 passes through the refrigerant flow switching device 6, the third heat source side refrigerant pipe 23, the first header main pipe 81, and the plurality of first header branch pipes 82. Configured to flow into. That is, in the second cooling operation mode, the refrigerant flow inside the second refrigerant flow switching device 7 that communicates with the fifth heat source side refrigerant pipe 25 branched from the branch portion 22a of the second heat source side refrigerant pipe 22. The path is blocked by a termination member 7 a connected to the second refrigerant flow switching device 7. Therefore, in the second cooling operation mode, the high-temperature and high-pressure gas refrigerant that has flowed into the second heat source side refrigerant pipe 22 does not flow into the region B of the heat source side heat exchanger 8. Other operations of the refrigeration cycle circuit are the same as those in the first cooling operation mode.

Next, control processing of the control device 90 of the air-conditioning apparatus 1 according to Embodiment 1 in the second cooling operation mode will be described.

As in the first cooling operation mode, the control device 90 changes the refrigerant flow path in the first refrigerant flow switching device 6 from the second heat source side refrigerant pipe 22 to the third heat source side refrigerant pipe 23. The refrigerant flows and communicates so that the refrigerant flows from the tenth heat source side refrigerant pipe 30 to the eleventh heat source side refrigerant pipe 31. Further, as described above, the control device 90 causes the refrigerant flow path inside the second refrigerant flow switching device 7 to which the termination member 7a is connected to communicate with the fifth heat source side refrigerant pipe 25 so that the high temperature and high pressure Control is performed so that the gas refrigerant does not flow into the region B of the heat source side heat exchanger 8.

Further, the control device 90 moves the refrigerant flow path of the flow path switching valve 55 provided in the seventh heat source side refrigerant pipe 27 from the seventh heat source side refrigerant pipe 27 to the third header main pipe 88 side. The heat source side branch refrigerant pipe 57 is communicated so that the refrigerant flows. By switching the flow path of the flow path switching valve 55, the refrigerant that stays (sleeps) in the region B of the heat source side heat exchanger 8 is changed to the second heat source side branch refrigerant pipe 53, the third heat source side branch refrigerant pipe 57, And it can return to the accumulator 18 via the 12th heat source side refrigerant | coolant piping 32. FIG. Therefore, in the second cooling operation mode, it is possible to prevent an increase in high pressure due to the refrigerant staying in the region B of the heat source side heat exchanger 8 (high stopping), and the compressor is reduced by reducing the high pressure. Therefore, the energy consumption of the air conditioner 1 can be reduced.

The control of the operation frequency of the compressor 2 and the control of the opening degree of the load side pressure reducing device 14 in the control device 90 are the same as the control processing in the first cooling operation mode.

Next, control processing of the electromagnetic valve 63 and the flow rate adjustment valve 67 by the control device 90 of the air-conditioning apparatus 1 according to Embodiment 1 in the second cooling operation mode will be described with reference to FIG. FIG. 6 is a flowchart illustrating an example of a control process in the second cooling operation mode in the control device 90 of the air-conditioning apparatus 1 according to Embodiment 1. It is assumed that the cooling operation in the first cooling operation mode is performed in the air conditioner 1 at the start of control processing of the electromagnetic valve 63 and the flow rate adjustment valve 67.

In step S11, whether or not the outside air temperature T detected by the first temperature sensor 73 is less than the lower limit value T0 of the standard temperature range of the outside air temperature, or the operating capacity V of the indoor unit 200 is standard. It is determined in control device 90 whether or not the lower limit value V0 of the range of the correct operating capacity. For example, the lower limit value T0 of the standard temperature range of the outside air temperature is set to 25 ° C. The lower limit value V0 of the standard operating capacity range is set to 50% of the total operating capacity. When it is determined that the outside air temperature T is equal to or higher than the lower limit value T0 or the operating capacity V of the indoor unit 200 is equal to or higher than the lower limit value V0, the operation in the first cooling operation mode is continued, The determination process is performed regularly (for example, once an hour).

The outside temperature T detected by the first temperature sensor 73 is less than the lower limit value T0 of the standard temperature range of the outside temperature, or the operating capacity V of the indoor unit 200 is the lower limit of the standard operating capacity range. When it is determined that the value is less than the value V0, in step S12, the control device 90 opens the electromagnetic valve 63 and opens the flow rate adjustment valve 67 at a predetermined opening. The predetermined opening is an opening at which the amount of refrigerant flowing out from the receiver 60 is smaller than the amount of refrigerant flowing into the receiver 60. When the refrigerant flows out from the outflow pipe 60c, the refrigerant is stored in the storage 60a of the receiver 60. The amount can be prevented from decreasing. For example, the opening degree of the flow rate adjusting valve 67 can be set to about 1/8 when the opening degree of the flow rate adjusting valve 67 is 1 and the opening degree of the closed state is 0. In addition, the refrigerant temperature detected by the second temperature sensor 74 is subtracted from the saturation temperature (condensation temperature) calculated from the pressure detected by the first pressure sensor 70, thereby causing an excess in the heat source side heat exchanger 8. The degree of cooling ΔT is calculated, and the opening degree of the flow rate adjusting valve 67 is controlled so that the degree of supercooling ΔT becomes a predetermined temperature width ΔT0 (for example, 3 ° C.). In step S <b> 12, the refrigerant can be stored in the storage 60 a of the receiver 60 by the dead weight of the refrigerant by opening the electromagnetic valve 63 and the pressure difference generated in the flow rate adjustment valve 67 by opening the flow rate adjustment valve 67.

In step S13, the control device 90 subtracts the refrigerant temperature detected by the second temperature sensor 74 from the saturation temperature (condensation temperature) calculated from the pressure detected by the first pressure sensor 70. The degree of supercooling ΔT in the heat source side heat exchanger 8 is calculated.

Then, the control device 90 determines whether or not the degree of supercooling ΔT in the heat source side heat exchanger 8 is less than a predetermined temperature range ΔT0 (for example, 3 ° C.). That is, the control device 90 determines how much the refrigerant in the region A of the heat source side heat exchanger 8 becomes liquid refrigerant and exists in the refrigerant circuit as a surplus, based on the degree of supercooling ΔT in the heat source side heat exchanger 8. To do. Since it can be determined that the larger the degree of supercooling ΔT is, the more excess refrigerant is in the region A of the heat source side heat exchanger 8 of the refrigerant circuit, the electromagnetic valve 63 and the flow rate adjustment until this difference reaches a predetermined value. The operation of the valve 67 is maintained. The predetermined temperature range ΔT0 may not be a fixed value. For example, the predetermined temperature range ΔT0 may be decreased as the value of the outside air temperature T detected by the first temperature sensor 73 decreases. Further, the predetermined temperature range ΔT0 may be decreased as the operating capacity of the indoor unit 200 decreases.

When it is determined in step S13 that the degree of supercooling ΔT is equal to or greater than the predetermined temperature range ΔT0, the electromagnetic valve 63 is maintained open and the flow rate adjustment valve 67 is maintained open at a predetermined opening. ing. In step S15, whether or not the outside air temperature T detected by the first temperature sensor 73 is less than the lower limit value T0 of the standard temperature range of the outside air temperature, or the operating capacity V of the indoor unit 200 is standard. It is determined in the control device 90 whether or not the lower limit value V0 of the operating capacity range. The outside temperature T detected by the first temperature sensor 73 is less than the lower limit value T0 of the standard temperature range of the outside temperature, or the operating capacity V of the indoor unit 200 is the lower limit of the standard operating capacity range. If it is determined that the value is less than the value V0, the control device 90 performs the determination process in step S13 again. The outside temperature T detected by the first temperature sensor 73 is not less than the lower limit value T0 of the standard temperature range of the outside temperature, or the operating capacity V of the indoor unit 200 is the lower limit of the standard operating capacity range. If it is determined that the value is equal to or greater than V0, in step S17, the control device 90 closes the electromagnetic valve 63, opens the flow rate adjustment valve 67 at a predetermined opening degree, and the cooling operation is performed in the first cooling mode. Thus, the control process ends.

When it is determined in step S13 that the degree of supercooling ΔT is less than the predetermined temperature range ΔT0, the controller 90 closes the electromagnetic valve 63, closes the flow rate adjustment valve 67, and closes the receiver 60 in step S14. The refrigerant is confined in the storage 60a. At the time of the control process in step S14, the amount of refrigerant flowing through the area A of the heat source side heat exchanger 8 is an appropriate amount.

In step S16, whether or not the outside air temperature T detected by the first temperature sensor 73 is less than the lower limit value T0 of the standard temperature range of the outside air temperature, or the operating capacity V of the indoor unit 200 is standard. It is determined in the control device 90 whether or not the lower limit value V0 of the operating capacity range. The outside temperature T detected by the first temperature sensor 73 is less than the lower limit value T0 of the standard temperature range of the outside temperature, or the operating capacity V of the indoor unit 200 is the lower limit of the standard operating capacity range. When it is determined that the value is less than the value V0, the control device 90 closes the electromagnetic valve 63 and maintains the flow rate adjustment valve 67, and the determination process of step S16 is performed again. The outside temperature T detected by the first temperature sensor 73 is not less than the lower limit value T0 of the standard temperature range of the outside temperature, or the operating capacity V of the indoor unit 200 is the lower limit of the standard operating capacity range. If it is determined that the value is equal to or greater than V0, in step S17, the control device 90 closes the electromagnetic valve 63, opens the flow rate adjustment valve 67 at a predetermined opening degree, and the cooling operation is performed in the first cooling mode. Thus, the control process ends.

Next, the effect of the present invention according to the first embodiment will be described.

The air conditioner 1 according to the first embodiment includes a compressor 2 that compresses a refrigerant, and heat source side heat that is divided into a plurality of regions (for example, a region A and a region B) that perform heat exchange between the refrigerant and outside air. Exchanger 8, a refrigerant flow switching device (first refrigerant flow switching) that changes the flow direction of refrigerant passing through the heat source side heat exchanger 8 divided into a plurality of regions (for example, region A and region B). Device 6, second refrigerant flow switching device 7), a decompression device (first heat source side decompression device 12, load side decompression device 14) for decompressing the refrigerant, and heat exchange between the refrigerant and the indoor space 700. Refrigeration cycle circuit for circulating the refrigerant by connecting the load side heat exchanger 16 to be piped, and refrigerant pipe between the heat source side heat exchanger 8 and the load side heat exchanger 16 (eighth heat source side refrigerant pipe 28) From the refrigerant pipe connected to the suction side of the compressor 2 (fourth heat source side branch refrigerant pipe 61 The refrigerant | coolant piping (8th heat source side) between the receiver 60 provided in the middle of the 5th heat source side branch refrigerant | coolant piping 65) and the heat source side heat exchanger 8 and the load side heat exchanger 16 is provided. A first valve (for example, an electromagnetic valve 63) provided in a refrigerant pipe (fourth heat source side branch refrigerant pipe 61) branched from the refrigerant pipe 28) and connected to the inflow pipe 60b side of the receiver 60; A second valve (for example, a flow rate adjusting valve 67) provided in a refrigerant pipe (fifth heat source side branch refrigerant pipe 65) connected to the outlet side of the compressor 60 and connected to the suction side of the compressor 2; When the cooling load of the heat exchanger 16 is smaller than a predetermined value, only the lower heat source side heat exchanger (part of the region A of the heat source side heat exchanger 8) of the heat source side heat exchanger 8 is used. The receiver 60 includes a control device 90 that performs control for storing the refrigerant.

According to the configuration of the first embodiment, the control device 90 determines that the cooling load is small from the outside air temperature and the capacity of the indoor unit 200, and also determines that the amount of refrigerant in the heat source side heat exchanger 8 is large. In this case, the refrigerant can be stored in the storage 60 a of the receiver 60 by opening the electromagnetic valve 63 and setting the flow rate adjustment valve 67 to a predetermined opening degree. In the air conditioner 1 of the first embodiment, by storing the refrigerant in the storage 60a of the receiver 60, the refrigerant amount of the heat source side heat exchanger 8 is made appropriate, the high pressure is reduced, and the operating load of the compressor 2 ( Input) can be reduced. Therefore, according to the configuration of the first embodiment, the air conditioner 1 can be operated efficiently, and the air conditioner 1 that can reduce the energy consumption of the air conditioner 1 can be provided. Further, when the cooling load of the load side heat exchanger 16 is smaller than a predetermined value, the volume of the heat source side heat exchanger 8 through which the refrigerant flows can be reduced by using only the area A of the heat source side heat exchanger 8. Can be reduced.

Moreover, in the air conditioning apparatus 1 of the first embodiment, the control device 90 sets the first valve (for example, the electromagnetic valve 63) when the cooling load of the load-side heat exchanger 16 is smaller than a predetermined value. The second valve (for example, the flow rate adjusting valve 67) is opened to a predetermined opening degree. According to the above-described configuration, the liquid refrigerant flowing from the heat source side heat exchanger 8 can be stored in the receiver 60 due to the weight of the refrigerant and the pressure difference between the receiver 60 and the suction side of the compressor 2.

Embodiment 2. FIG.
In the second embodiment of the present invention, a third cooling operation mode that is a modification of the cooling operation mode in the air-conditioning apparatus 1 according to the above-described first embodiment will be described. The configuration of the air conditioner 1 and the operation of the refrigeration cycle circuit according to Embodiment 2 of the present invention are the same as those in the first cooling operation mode of Embodiment 1 described above.

In the “third cooling operation mode”, the outside air temperature exceeds the upper limit (for example, 43 ° C.) of the standard temperature range of the outside air temperature in the first cooling operation mode, and the high pressure is standard. The cooling operation performed by the air-conditioning apparatus 1 according to Embodiment 1 when the upper limit (for example, 36 kg / cm ² ) of the range of a typical high pressure is exceeded.

A control process of the control device 90 of the air-conditioning apparatus 1 according to Embodiment 2 in the third cooling operation mode will be described. In the control device 90, the first refrigerant flow switching device 6, the second refrigerant flow switching device 7, the flow switching valve 55, the operating frequency of the compressor 2, and the opening degree of the load side pressure reducing device 14 are set. The control is the same as the control process in the first cooling operation mode.

Hereinafter, control processing of the electromagnetic valve 63 and the flow rate adjustment valve 67 of the control device 90 of the air-conditioning apparatus 1 according to Embodiment 2 in the third cooling operation mode will be described with reference to FIG. FIG. 7 is a flowchart illustrating an example of a control process in the third cooling operation mode in the control device 90 of the air-conditioning apparatus 1 according to Embodiment 2. It is assumed that the cooling operation in the first cooling operation mode is performed in the air conditioner 1 when the control process by the control device 90 is started.

In step S21, whether or not the outside air temperature T detected by the first temperature sensor 73 exceeds the upper limit value T1 of the standard temperature range of the outside air temperature, and the high pressure detected by the first pressure sensor 70. The controller 90 determines whether or not the pressure P exceeds the upper limit value P1 of the standard high pressure range. For example, the upper limit value T1 of the standard temperature range of the outside air temperature is set to 43 ° C. The upper limit value P1 of the standard high pressure range is set to 36 kg / cm ² . When it is determined that the outside air temperature T is equal to or lower than the upper limit value T1 and the high pressure P is equal to or lower than the upper limit value P1, the operation in the first cooling operation mode is continued, and the determination process in step S21 is periodically performed. (For example, once an hour).

The outside temperature T detected by the first temperature sensor 73 exceeds the upper limit value T1 of the standard temperature range of the outside temperature, and the high pressure P detected by the first pressure sensor 70 is the standard high pressure. If it is determined that the upper limit value P1 of the pressure range is exceeded, in step S22, the control device 90 opens the electromagnetic valve 63 and opens the flow rate adjustment valve 67 at a predetermined opening. The predetermined opening is an opening at which the amount of refrigerant flowing out from the receiver 60 is smaller than the amount of refrigerant flowing into the receiver 60. When the refrigerant flows out from the outflow pipe 60c, the refrigerant is stored in the storage 60a of the receiver 60. Prevent the amount from decreasing. For example, the opening degree of the flow rate adjusting valve 67 can be set to about 1/8 when the opening degree of the flow rate adjusting valve 67 is 1 and the opening degree of the closed state is 0. Further, the opening degree of the flow rate adjustment valve 67 can be adjusted so that the value of the high pressure detected by the first pressure sensor 70 is reduced to the upper limit value P1 or less. In step S <b> 22, the refrigerant can be stored in the storage 60 a of the receiver 60 by the dead weight of the refrigerant by opening the electromagnetic valve 63 and the pressure difference generated in the flow rate adjustment valve 67 by opening the flow rate adjustment valve 67.

In step S23, the controller 90 determines whether or not the high pressure P detected by the first pressure sensor 70 is equal to or lower than the upper limit value P1 of the standard high pressure range. When it is determined that the high pressure P detected by the first pressure sensor 70 exceeds the upper limit value P1 of the standard high pressure range, the control device 90 periodically performs the determination process in step S23.

When it is determined that the high pressure P detected by the first pressure sensor 70 is equal to or lower than the upper limit value P1 of the standard high pressure range, in step S24, the control device 90 closes the electromagnetic valve 63. The flow regulating valve 67 is closed and the refrigerant is confined in the storage 60 a of the receiver 60.

In step S25, the controller 90 determines whether or not the high pressure P detected by the first pressure sensor 70 is equal to or lower than the upper limit value P1 of the standard high pressure range. When it is determined that the high pressure P detected by the first pressure sensor 70 exceeds the upper limit value P1 of the standard high pressure range, the control device 90 performs the control process of step S22 and sets the electromagnetic valve 63. The flow control valve 67 is opened at a predetermined opening.

On the other hand, if the determination in step S25 is “Yes”, whether or not the outside temperature T detected by the first temperature sensor 73 exceeds the upper limit value T1 of the standard temperature range of the outside temperature in step S26. Is determined by the control device 90. When it is determined that the outside air temperature T detected by the first temperature sensor 73 exceeds the upper limit value T1 of the standard temperature range of the outside air temperature, the control device 90 closes the electromagnetic valve 63 and the flow rate adjusting valve. 67 is kept closed, and the determination process in step S25 is periodically performed. When it is determined that the outside air temperature T detected by the first temperature sensor 73 is equal to or lower than the upper limit value T1 of the standard temperature range of the outside air temperature, in step S27, the control device 90 causes the electromagnetic valve 63 to Is closed, the flow rate adjustment valve 67 is opened at a predetermined opening, the cooling operation is in the first cooling mode, and the control process is terminated.

As described above, the control device 90 in the air-conditioning apparatus 1 according to the second embodiment has the cooling load on the load side heat exchanger 16 and the receiver 60 receives the air temperature when the outside air temperature is higher than a predetermined value. It controls to store the refrigerant. According to the configuration of the second embodiment, the control device 90 determines that suppression of the high pressure is necessary based on the information on the outside air temperature by the first temperature sensor 73 and the information on the high pressure by the first pressure sensor 70. In this case, the refrigerant can be stored in the storage 60 a of the receiver 60 by opening the electromagnetic valve 63 and setting the flow rate adjustment valve 67 to a predetermined opening. Therefore, according to the second embodiment, the amount of refrigerant in the heat source side heat exchanger 8 is reduced, an increase in high pressure is suppressed, and air conditioning is caused by a high pressure abnormality (for example, a pressure of 38.5 kg / cm ² or more). The apparatus 1 can be prevented from abnormally stopping.

Embodiment 3 FIG.
In Embodiment 3 of the present invention, a heating operation mode in the air-conditioning apparatus 1 according to Embodiment 1 described above will be described. FIG. 8 is a schematic refrigerant circuit diagram illustrating a refrigerant flow in the heating operation mode of the air-conditioning apparatus 1 according to Embodiment 3. In FIG. 8, the flow direction of the refrigerant is indicated by solid line arrows.

An example of the operation of the refrigeration cycle circuit during the heating operation of the air-conditioning apparatus 1 according to Embodiment 3 will be described with reference to FIG.

Compressor 2 sucks and compresses low-temperature and low-pressure refrigerant and discharges high-temperature and high-pressure gas refrigerant. The high-temperature and high-pressure gas refrigerant discharged from the compressor 2 flows from the outdoor unit 100 into the indoor unit 200 through the first refrigerant flow switching device 6. The refrigerant flowing into the indoor unit 200 is condensed and liquefied while dissipating heat to the indoor space 700, and becomes a high-pressure liquid refrigerant. The high-pressure liquid refrigerant is decompressed and expanded when passing through the load-side decompression device 14, and becomes a low-temperature and low-pressure (gas-liquid) two-phase refrigerant. The two-phase refrigerant flows from the indoor unit 200 to the outdoor unit 100. The refrigerant that has flowed into the outdoor unit 100 flows into the heat source side heat exchanger 8 (including both the region A and the region B) that functions as an evaporator.

The refrigerant that has flowed into the heat source side heat exchanger 8 absorbs heat from the outside air in the heat source side heat exchanger 8, and becomes a low-temperature and low-pressure gas refrigerant. The low-temperature and low-pressure gas refrigerant that has flowed out of the heat source side heat exchanger 8 is again sucked into the compressor 2 via the first refrigerant flow switching device 6, the second refrigerant flow switching device 7, and the accumulator 18. .

Next, control processing of the control device 90 of the air-conditioning apparatus 1 according to Embodiment 3 in the heating operation mode will be described.

The control device 90 causes the refrigerant to flow through the refrigerant flow path inside the first refrigerant flow switching device 6 from the second heat source side refrigerant pipe 22 to the tenth heat source side refrigerant pipe 30, and thereby the third heat source side refrigerant. The pipe 23 is connected to the eleventh heat source side refrigerant pipe 31 so that the refrigerant flows. In addition, the control device 90 causes the refrigerant flow path inside the second refrigerant flow switching device 7 to communicate so that the refrigerant flows from the sixth heat source side refrigerant pipe 26 to the twelfth heat source side refrigerant pipe 32. Further, the controller 90 connects the refrigerant flow path of the flow path switching valve 55 provided in the seventh heat source side refrigerant pipe 27 from the seventh heat source side refrigerant pipe 27 on the fourth header main pipe 88 side. The refrigerant is communicated with the seventh heat source side refrigerant pipe 27 on the 43 side so that the refrigerant flows. In addition, the control device 90 causes the refrigerant flow path inside the second refrigerant flow switching device 7 to which the termination member 7a is connected to communicate with the fifth heat source side refrigerant pipe 25 to thereby provide a fifth heat source side refrigerant pipe 25. The refrigerant flow is blocked.

Further, the control device 90 opens the electromagnetic valve 63 and fully opens the flow rate adjustment valve 67, thereby passing the inflow pipe 60 b of the receiver 60, the storage 60 a of the receiver 60, and the outflow pipe 60 c of the receiver 60 to the accumulator 18. A refrigerant flow path for returning the refrigerant is formed. That is, the control device 90 opens the electromagnetic valve 63 and fully opens the flow rate adjustment valve 67, so that a part of the refrigerant that leaves the load side heat exchanger 16 and goes to the heat source side heat exchanger 8 is heated to the heat source side heat. Control is performed to return the refrigerant to the accumulator 18 without going through the exchanger 8.

The control device 90 calculates a saturation temperature (condensation temperature) in the load-side heat exchanger 16 from the pressure detected by the first pressure sensor 70. The controller 90 subtracts the refrigerant temperature detected by the third temperature sensor 75 from the calculated condensation temperature, calculates the degree of supercooling in the refrigeration cycle circuit of the air conditioner 1, and the degree of supercooling is a predetermined temperature range. (For example, 5 degreeC) The opening degree of the load side decompression device 14 is controlled. Further, the control device 90 controls the operating frequency of the compressor 2 so that the condensation temperature becomes the target temperature. The target value of the condensation temperature may be a fixed value (for example, 30 ° C.), or an indoor temperature sensor (not shown) is arranged in the indoor space 700 of FIG. The controller 90 may be configured to change the target temperature by calculating the maximum value of the set temperature difference to be set by the controller 90. Moreover, the 2nd heat-source side decompression device 13 may be open | released and may be closed.

As described above, in the air-conditioning apparatus 1 of Embodiment 3, when the load-side heat exchanger 16 has a heating load, the control device 90 is a part of the refrigerant that has come out of the load-side heat exchanger 16. Is returned to the compressor 2 via the receiver 60 without passing through the heat source side heat exchanger 8. According to the third embodiment, the pressure loss due to passing through the heat source side heat exchanger 8 can be reduced, so that the low pressure reduction can be suppressed, frost formation due to the low pressure reduction and the circulation amount discharged from the compressor 2 can be suppressed. Reduction can be suppressed.

Embodiment 4 FIG.
In the fourth embodiment of the present invention, the refrigerant recovery mode when the refrigerant leaks into the indoor space 700 in the air-conditioning apparatus 1 according to the first embodiment described above will be described. Note that the configuration of the air-conditioning apparatus 1 and the operation of the refrigeration cycle circuit according to Embodiment 4 of the present invention are the same as those in the first cooling operation mode of Embodiment 1 described above.

When the indoor unit control device 95 detects from the signal from the refrigerant leak detection sensor 78 that the refrigerant is leaking into the indoor space 700, a refrigerant leak signal is transmitted to the control device 90 via the transmission line 98.

The control device 90 passes through the first refrigerant flow switching device 6 and the second refrigerant flow switching device 7 of the outdoor unit 100 so that the refrigerant discharged from the compressor 2 flows into the heat source side heat exchanger 8. Switch to the same refrigerant flow path as in the first cooling operation mode. The control device 90 moves the refrigerant flow path of the flow path switching valve 55 provided in the seventh heat source side refrigerant pipe 27 from the seventh heat source side refrigerant pipe 27 on the fourth header main pipe 88 side to the connection member 43. The refrigerant is communicated with the seventh heat source side refrigerant pipe 27 so that the refrigerant flows.

The control device 90 opens the electromagnetic valve 63, and the flow rate adjustment valve 67 has a predetermined opening degree (for example, when the opening degree of the flow adjustment valve 67 is 1 and the opening degree of the closed state is 0, 1 / 8). Further, the control device 90 determines the flow rate adjustment valve based on the difference in the refrigerant temperature detected by the second temperature sensor 74 from the saturation temperature (condensation temperature) calculated from the pressure detected by the first pressure sensor 70. The opening degree of 67 can be changed. The first heat source side decompression device 12 is closed. The load side decompression device 14 is fully opened.

In the refrigerant recovery mode, the compressor 2 sucks low-temperature and low-pressure refrigerant and discharges high-temperature and high-pressure gas refrigerant. The high-temperature and high-pressure gas refrigerant discharged from the compressor 2 flows into the heat source side heat exchanger 8 via the first refrigerant flow switching device 6 and the second refrigerant flow switching device 7. Since the first heat source side decompression device 12 is closed, the refrigerant is stored in the heat source side heat exchanger 8. Since there is no refrigerant flowing into the indoor unit 200, the refrigerant in the indoor unit 200 is collected by the outdoor unit 100. Further, the refrigerant collected in the outdoor unit 100 is also stored in the storage 60 a of the receiver 60 via the electromagnetic valve 63 and the inflow pipe 60 b of the receiver 60.

As described above, in the air-conditioning apparatus 1 according to the fourth embodiment, when the control device 90 detects that the refrigerant is leaking in the indoor space 700, the heat source side heat exchanger 8 and the receiver 60 Both are controlled to store the refrigerant. According to the configuration of the fourth embodiment, when the indoor unit control device 95 detects refrigerant leakage from the refrigerant leakage detection sensor 78, the control device 90 supplies the refrigerant to the receiver 60 in addition to the heat source side heat exchanger 8. Can be stored. Therefore, according to the configuration of the fourth embodiment, in the refrigerant recovery mode, it is possible to recover a large amount of refrigerant in the outdoor unit 100 and reduce the refrigerant flowing out into the indoor space 700.

Other embodiments.
The present invention is not limited to the above-described embodiment, and various modifications can be made. For example, in the above-described embodiment, the installation position of the control device 90 is not particularly limited. For example, the outdoor unit 100 or the indoor unit 200 may be used. Moreover, the air conditioning apparatus 1 of the above-described embodiment may include two or more control devices 90.

In the above-described embodiment, the control device 90 closes the electromagnetic valve 63 in step S17 in the first cooling operation mode, the second cooling operation mode, or step S27 in the third cooling operation mode. However, the electromagnetic valve 63 may be opened for a certain period. When the electromagnetic valve 63 is opened, the pressure difference generated by the flow rate adjustment valve 67 increases, so that the refrigerant stored in the storage 60 a of the receiver 60 is transferred to the fifth heat source side branch refrigerant pipe 65 and the twelfth heat source side refrigerant pipe 32. It is possible to increase the flow rate of the refrigerant flowing through the accumulator 18 via.

Further, the above-described embodiments can be used in combination with each other.

1 air conditioner, 2 compressor, 4 oil separator, 6 first refrigerant flow switching device, 7 second refrigerant flow switching device, 7a termination member, 8 heat source side heat exchanger, 10 supercooling heat exchange 12, 1st heat source side pressure reducing device, 13 2nd heat source side pressure reducing device, 14 load side pressure reducing device, 16 load side heat exchanger, 18 accumulator, 20 control device, 21 1st heat source side refrigerant piping, 22 2nd heat source side refrigerant pipe, 22a Branch part of 2nd heat source side refrigerant pipe, 23 3rd heat source side refrigerant pipe, 24 4th heat source side refrigerant pipe, 25 5th heat source side refrigerant pipe, 26 6th Heat source side refrigerant piping, 27 seventh heat source side refrigerant piping, 28 eighth heat source side refrigerant piping, 28a branching portion of eighth heat source side refrigerant piping, 29 ninth heat source side refrigerant piping, 29a ninth heat source Branch of side refrigerant piping, 3 10th heat source side refrigerant pipe, 31 eleventh heat source side refrigerant pipe, 32 twelfth heat source side refrigerant pipe, 32a first branch portion of twelfth heat source side refrigerant pipe, 32b twelfth heat source side refrigerant pipe 2nd branch part, 32c 3rd branch part of 12th heat source side refrigerant pipe, 33 13th heat source side refrigerant pipe, 35 1st load side refrigerant pipe, 36 2nd load side refrigerant pipe, 41 reverse Stop valve, 43 connecting member, 45a first strainer, 45b second strainer, 47a first heat source side connection valve, 47b second heat source side connection valve, 49a first joint part, 49b second joint part , 51 1st heat source side branch refrigerant pipe, 53 2nd heat source side branch refrigerant pipe, 53a branching section, 55 flow path switching valve, 57 3rd heat source side branch refrigerant pipe, 60 receiver, 60a storage, 6 b Inflow pipe, 60c Outflow pipe, 60d Leg, 61 Fourth heat source side branch refrigerant pipe, 63 Solenoid valve, 65 Fifth heat source side branch refrigerant pipe, 67 Flow control valve, 70 First pressure sensor, 71st 2 pressure sensors, 73 first temperature sensor, 74 second temperature sensor, 75 third temperature sensor, 76 fourth temperature sensor, 78 refrigerant leakage detection sensor, 81 first header main pipe, 82 first Header branch pipe, 83 Second header branch pipe, 84 Second header main pipe, 85 Third header main pipe, 86 Third header branch pipe, 87 Fourth header branch pipe, 88 Fourth header main pipe, 90 Control device, 95 indoor unit control device, 98 transmission line, 100 outdoor unit, 200 indoor unit, 300 first communication piping, 400 second communication piping, 500 building, 6 00 outdoor space, 700 indoor space, 800 under floor piping.

Claims

The compressor that compresses the refrigerant, the heat source side heat exchanger that is divided into a plurality of regions that perform heat exchange between the refrigerant and the outside air, and the heat source side heat exchanger that is divided into the plurality of regions. A refrigerant flow switching device that changes the flow direction of the refrigerant, a decompression device that depressurizes the refrigerant, and a refrigeration that circulates the refrigerant by piping connection to a load-side heat exchanger that exchanges heat between the refrigerant and the indoor space A cycle circuit;
A receiver for storing the refrigerant, which is branched from a refrigerant pipe between the heat source side heat exchanger and the load side heat exchanger and provided in the middle of the refrigerant pipe connected to the suction side of the compressor;
A first valve provided in the refrigerant pipe branched from the refrigerant pipe between the heat source side heat exchanger and the load side heat exchanger and connected to the inlet side of the receiver;
A second valve provided in a refrigerant pipe connected to the outlet side of the receiver and connected to the suction side of the compressor;
When the cooling load of the load side heat exchanger is smaller than a predetermined value, only a part of the heat source side heat exchanger divided into the plurality of regions is used, and the receiver An air conditioning apparatus comprising: a control device that performs control for storing refrigerant.
The control device opens the first valve and opens the second valve to a predetermined opening when a cooling load of the load-side heat exchanger is smaller than a predetermined value. The air conditioning apparatus according to claim 1.
The air conditioner according to claim 1, wherein the control device performs control to store the refrigerant in the receiver when the load-side heat exchanger has a cooling load and an outside air temperature is higher than a predetermined value.
When there is a heating load in the load side heat exchanger, the control device passes a part of the refrigerant from the load side heat exchanger through the receiver without passing through the heat source side heat exchanger. The air conditioning apparatus according to claim 1, wherein control for returning to the compressor is performed.
5. The control device according to claim 1, wherein, when detecting that the refrigerant leaks in the indoor space, the control device performs control to store the refrigerant in both the heat source side heat exchanger and the receiver. The air conditioning apparatus according to one item.