JP2011257020A - Air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air conditioner capable of easily manufacturing and managing heat source machines in air conditioners of different types.SOLUTION: An outdoor unit 51 has a compressor 1 compressing the refrigerant, an outdoor heat exchanger 2 carrying out heat exchange between outside air and the refrigerant, and a four-way valve 3. An indoor unit 52 has an indoor heat exchanger 5 carrying out heat exchange between air and the refrigerant, and an indoor throttle device 6. Either a refrigerant heat exchange unit 55 having a heat exchange throttle device 7 decompressing the refrigerant and a refrigerant heat exchanger 8 supercooling the refrigerant flowing from an indoor unit 51 side to an outdoor unit 52 side, or a combination of a relay 54 forming a passage supplying gas refrigerant to the indoor unit 52 carrying out heating and supplying liquid refrigerant to the indoor unit 52 carrying out cooling and a refrigerant flow regulating unit 53 regulating a flow of the refrigerant between the outdoor unit 51 and the relay 54, is connected by piping between the outdoor unit 51 and the indoor unit 52.

Description

  The present invention relates to an air conditioner. In particular, a plurality of types of air conditioners can be efficiently produced and managed.

  There are several types of air conditioners (systems) having a plurality of indoor units installed in buildings such as buildings. For example, there is a cooling / heating switching type air conditioner in which all indoor units in operation can perform either cooling or heating. There is also a cooling and heating simultaneous operation type air conditioner that can perform operation by arbitrarily selecting cooling or heating in each indoor unit related to operation.

  Such a cooling / heating switching type air conditioner and a cooling / heating simultaneous operation type air conditioner have different configurations of heat source units. For this reason, the heat source machine used for each type is manufactured separately, and management is also performed separately (for example, refer to patent documents 1).

JP 2009-121707 A

  As described above, since the heat source units of different types of air conditioners were manufactured separately, it took time and effort to separate the parts, and it took a lot of time to sort and assemble the parts by changing the assembly.

  In addition, since the cooling / heating switching type air conditioner and the cooling / heating simultaneous operation type air conditioner are managed separately, only one of the air conditioners may increase in stock or run out of stock. It was.

  Then, it aims at obtaining the air conditioning apparatus which can manufacture and manage the heat source machine in a different type air conditioning apparatus efficiently.

  The air conditioner of the present invention includes a compressor that compresses and discharges a refrigerant, an outdoor heat exchanger that exchanges heat between the outside air and the refrigerant, an outdoor unit that has a four-way valve, and heat exchange between air to be conditioned and the refrigerant. An indoor unit having an indoor heat exchanger and an indoor expansion device to perform, a heat exchange expansion device that decompresses a part of the refrigerant flowing from the outdoor unit, and an indoor unit from the outdoor unit side by heat exchange with the refrigerant that has passed through the heat exchange expansion device To supply a refrigerant heat exchanger unit having a refrigerant heat exchanger that supercools the refrigerant flowing to the unit side, or an indoor unit that performs heating, and a liquid refrigerant to an indoor unit that performs cooling One of a combination of a relay that forms the flow path of the refrigerant and a refrigerant flow control unit that controls the flow of refrigerant between the outdoor unit and the relay is used as an outdoor unit and an indoor unit. And it constitutes a refrigerant circuit by piping connection between.

  According to the present invention, either a refrigerant heat exchanger unit or a combination of a relay machine and a refrigerant flow control unit is connected between an outdoor unit and an indoor unit having a compressor, an outdoor heat exchanger, and a four-way valve. Since the air conditioner is configured as described above, the outdoor unit can be shared by different types of air conditioners, and it is not necessary to separately manufacture and manage the heat source unit. For this reason, productivity can be improved and inventory management can be made easy. In addition, the type (system) can be changed even after installation.

1 is a diagram illustrating a configuration of a cooling / heating switching type air conditioning apparatus according to Embodiment 1. FIG. It is a figure showing the structure of the cooling-heating simultaneous operation type air conditioning apparatus which concerns on Embodiment 1. FIG. It is a figure showing the structure of the air conditioning apparatus which concerns on Embodiment 2 of this invention. It is a figure showing the relationship of the apparatus which concerns on the control in the air conditioning apparatus of Embodiment 2. FIG. It is a figure which shows the flowchart of the process which determines the operating frequency etc. of the compressor. It is a figure which shows the flowchart of the process which determines the opening degree of the heat exchange expansion device. It is a figure which shows the flowchart of the process which determines the opening degree of the indoor expansion device. It is a figure showing the structure of the air conditioning apparatus which concerns on Embodiment 3 of this invention. It is a figure showing the relationship of the apparatus which concerns on the control in the air conditioning apparatus of Embodiment 2. FIG. It is a figure which shows the flowchart of the process which determines the operating frequency etc. of the compressor. It is a figure which shows the flowchart which determines the opening degree of the heat exchange expansion device 7a, 7b. It is a figure showing the relationship of the apparatus which concerns on the control in the air conditioning apparatus of Embodiment 4. FIG. It is a figure showing the relationship of the apparatus which concerns on the control in the air conditioning apparatus of Embodiment 5. FIG.

Embodiment 1 FIG.
FIG. 1 is a diagram illustrating a configuration of a cooling / heating switching type air conditioner according to Embodiment 1 of the present invention. As shown in FIG. 1, the cooling / heating switching type air conditioner according to the present embodiment is connected to a refrigerant heat exchanger unit 55 between an outdoor unit 51 and an indoor unit 52 to circulate refrigerant. A refrigeration cycle). In the present embodiment, the indoor unit 52 and the refrigerant heat exchanger unit 55 are connected by a liquid pipe 101 and a gas pipe 102 which are refrigerant pipes. Here, the level of the pressure in the refrigerant circuit is not related to the reference pressure, but represents the level of the relative pressure generated by the compression of the compressor or the like, or the pressure reduction by the refrigerant flow control or the like. The same applies to the temperature level.

[Outdoor unit 51]
The outdoor unit 51 of the present embodiment is configured by connecting the compressor 1, the four-way valve 3, the outdoor heat exchanger 2, and the accumulator 4 by piping. The compressor 1 compresses and discharges the sucked refrigerant. Here, although not particularly limited, the compressor 1 can change the capacity of the compressor 1 (the amount of refrigerant sent out per unit time) by arbitrarily changing the operation frequency, for example, by an inverter circuit or the like. You may be able to. The outdoor heat exchanger 2 performs heat exchange between the refrigerant and air (outdoor air). For example, it functions as an evaporator during heating operation, evaporating and evaporating the refrigerant. Moreover, it functions as a condenser during the cooling operation, and condenses and liquefies the refrigerant. The four-way valve 3 is a valve for switching the flow of refrigerant according to, for example, a cooling operation and a heating operation. The accumulator 4 is means for storing, for example, liquid surplus refrigerant.

[Refrigerant heat exchanger unit 55]
The refrigerant heat exchanger unit 55 is configured by connecting the heat exchange expansion device 7, the refrigerant heat exchanger 8, and the check valve 9 by piping. Here, in the refrigerant heat exchanger unit 55, the refrigerant is branched by using a part of the pipe between the refrigerant heat exchanger 8 and the liquid pipe 101 as a branch pipe, and a part of the refrigerant flows to the heat exchange expansion device 7. I am doing so.

  The refrigerant heat exchanger 8 exchanges heat between the refrigerants. For example, during cooling operation, the refrigerant flowing from the outdoor unit 51 side to the liquid pipe 101 side is supercooled by exchanging heat with the refrigerant partially branched by the aforementioned branch pipe and passing through the heat exchange expansion device 7, Flow in liquid pipe 101. The heat exchange throttle device 7 functions as a pressure reducing valve or an expansion valve, and expands the refrigerant by reducing the pressure. Here, the heat exchange throttle device 7 is constituted by a flow rate control means capable of precisely controlling the flow rate by changing the opening degree, such as an electronic expansion valve, but an inexpensive refrigerant flow rate control such as a capillary tube, for example. You may comprise by a means. The check valve 9 is a valve for preventing the refrigerant from flowing backward and causing the refrigerant to flow in one direction.

[Indoor unit 52]
The indoor unit 52 is configured by connecting the indoor heat exchanger 5 and the indoor expansion device 6 in series. The indoor heat exchanger 5 performs heat exchange between the air to be air-conditioned and supplied by a blower (not shown) and the refrigerant. For example, it functions as a condenser during heating operation and condenses and liquefies the refrigerant. Moreover, it functions as an evaporator during cooling operation, evaporating and evaporating the refrigerant. The indoor expansion device 6 functions as a pressure reducing valve or an expansion valve, and expands the refrigerant by reducing the pressure. The indoor throttling device 6 may be composed of a flow rate control means such as the electronic expansion valve described above.

  Next, the operation of the cooling / heating switching air conditioner of FIG. 1 will be described based on the refrigerant flow in the refrigerant circuit. First, the operation of the refrigerant in the cooling operation will be described. A high-temperature, high-pressure gaseous refrigerant (hereinafter referred to as a gas refrigerant) that is compressed and discharged by the compressor 1 passes through the outdoor heat exchanger 2 from the four-way valve 3 and exchanges heat with outdoor air. Condensed and liquefied, for example, flows out of the outdoor unit 51 as a liquid refrigerant (hereinafter referred to as a liquid refrigerant).

  The refrigerant that has flowed into the refrigerant heat exchanger unit 55 passes through the refrigerant heat exchanger 8, and is then partially branched by the branch pipe and passes through the heat exchange expansion device 7. At this time, the refrigerant is decompressed. The decompressed refrigerant passes through the refrigerant heat exchanger 8 and cools the refrigerant flowing from the outdoor unit 51 by heat exchange. Thereby, the supercooling degree of the refrigerant | coolant which flows out out of the refrigerant | coolant heat exchanger unit 55 increases. The refrigerant that has flowed out of the refrigerant heat exchanger unit 55 passes through the liquid pipe 101 and flows into the indoor unit 52.

  The refrigerant flowing into the indoor unit 52 is depressurized by the indoor expansion device 6, passes through the indoor heat exchanger 5, and flows out of the indoor unit 52. At this time, in the indoor heat exchanger 5, the refrigerant is evaporated and vaporized (gasified) by heat exchange, and for example, air in the air-conditioning target space is cooled. Thereby, the air-conditioning target space is cooled.

  The refrigerant flowing out of the indoor unit 52 passes through the gas pipe 102 and the refrigerant heat exchanger unit 55 and flows into the outdoor unit 51. At this time, the refrigerant heat exchanger unit 55 merges with the refrigerant flowing from the check valve 9 side. The refrigerant flowing into the outdoor unit 51 is sucked into the compressor 1 through the four-way valve 3 and the accumulator 4, and circulates by being compressed and discharged as described above.

  Next, the operation of the refrigerant in the heating operation will be described. Since it is not necessary to supercool the refrigerant in the heating operation, the heat exchange throttle device 7 is closed so that the refrigerant does not branch. The high-temperature, high-pressure gas (gas) refrigerant compressed and discharged by the compressor 1 passes through the four-way valve 3 and flows out of the outdoor unit 51. The refrigerant flowing out of the outdoor unit 51 passes through the refrigerant heat exchanger unit 55 and the gas pipe 102 and flows into the indoor unit 52.

  The refrigerant that has flowed into the indoor unit 52 passes through the indoor heat exchanger 5. At this time, in the indoor heat exchanger 5, the refrigerant is condensed and liquefied by heat exchange, and for example, air in the air-conditioning target space is heated. Thereby, the air-conditioning target space is heated. The refrigerant that has passed through the indoor heat exchanger 5 is decompressed by the indoor expansion device 6 and flows out of the indoor unit 52.

  The refrigerant flowing out of the indoor unit 52 passes through the liquid pipe 101 and the refrigerant heat exchanger unit 55 and flows into the outdoor unit 51. The refrigerant that has flowed into the outdoor unit 51 passes through the outdoor heat exchanger 2, and evaporates and vaporizes by exchanging heat with, for example, outdoor air. Thereafter, the refrigerant is sucked into the compressor 1 through the four-way valve 2 and the accumulator 4, and circulated by being compressed and discharged as described above.

  FIG. 2 is a diagram showing the configuration of the cooling and heating simultaneous operation type air conditioner according to Embodiment 1 of the present invention. As shown in FIG. 2, the cooling and heating simultaneous operation type air conditioner in the present embodiment has a refrigerant flow control unit 53 and a relay 54 connected between an outdoor unit 51 and a plurality of indoor units 52a and 52b. A refrigerant circuit (refrigeration cycle) for circulating the refrigerant is configured. In the present embodiment, the outdoor unit 51 and the refrigerant flow control unit 53 are connected by a liquid pipe 101 and a gas pipe 102 which are refrigerant pipes. Further, the refrigerant flow control unit 53 and the relay 54 are connected by a low pressure pipe 103 and a high pressure pipe 104 which are refrigerant pipes. And the relay machine 54 and each indoor unit 52a, 52b are connected by liquid piping 105a, 105b and gas piping 106a, 106b which are refrigerant piping, respectively. Hereinafter, units, means, and the like may be described with subscripts omitted unless it is particularly necessary to distinguish or specify units.

[Outdoor unit 51]
The configuration of the outdoor unit 51 in the cooling / heating simultaneous operation type air conditioner is the same as the configuration of the outdoor unit 51 of the cooling / heating switching type air conditioner. For this reason, manufacture, management, etc. can be performed in common.

[Refrigerant flow control unit 53]
The refrigerant flow control unit 53 includes connection pipes 130 to 133 and check valves 10a to 10d. The connection pipe 130 is a pipe that connects a part of the connection pipe 133 near the liquid pipe 101 (connection part a) and a part of the connection pipe 132 from the high-pressure pipe 104 (connection part c). The connection pipe 131 is a pipe that connects a portion of the connection pipe 132 near the gas pipe 102 (connection portion d) and a portion of the connection pipe 133 near the high-pressure pipe 104 (connection portion b). Further, the connection pipe 132 is a pipe that connects the gas pipe 102 and the low-pressure pipe 103. The connection pipe 133 is a pipe that connects the liquid pipe 101 and the high-pressure pipe 104.

  The check valve 10a is provided between the connection part c and the connection part d of the connection pipe 132, and allows passage of the refrigerant flowing from the low-pressure pipe 103 (relay machine 54) to the gas pipe 102 (outdoor unit 51). To do. The check valve 10b is provided between the connection part a and the connection part b of the connection pipe 133, and the passage of the refrigerant flowing from the liquid pipe 101 (outdoor unit 51) to the high-pressure pipe 104 (relay machine 54). Is acceptable. Further, the check valve 10c is provided in the connection pipe 131 and allows passage of the refrigerant flowing from the gas pipe 102 (connection portion d) to the high-pressure pipe 104 (connection portion b). The check valve 10d is provided in the connection pipe 131 and allows passage of the refrigerant flowing from the low-pressure pipe 103 (connection part c) toward the liquid pipe 101 (connection part a).

[Repeater 54]
The relay unit 54 is configured so that each indoor unit 52 can be operated between the indoor unit 52 and the refrigerant flow control unit 53 (outdoor unit 51) so that each indoor unit 52 can be individually cooled or heated. Control the flow of refrigerant to the. Therefore, the relay 54 includes the gas-liquid separator 11, the first on-off valves 12a and 12b, the second on-off valves 13a and 13b, the first throttling device 14, the second throttling device 15, the first refrigerant heat exchanger 16, The second refrigerant heat exchanger 17, the bypass pipe 110, and the connection pipes 111 and 112 are configured.

  The gas-liquid separator 11 separates the refrigerant flowing from the high-pressure pipe 104 into a gas refrigerant and a liquid refrigerant. The liquid refrigerant flows through the connection pipe 111, and the gas refrigerant flows through the connection pipe 112. The first on-off valve 12 controls the passage and blocking of the refrigerant between the connection pipe 112 and the gas pipe 106 by opening and closing. In the present embodiment, two first on-off valves 12a and 12b are provided in accordance with the number of gas pipes 106 (indoor units 52) (for this reason, the connecting pipe 112 branches into two on the way). When the corresponding indoor unit 52 is heating, it is opened to allow the refrigerant to pass therethrough, and when cooling is being performed, the indoor unit 52 is closed to block the passage of the refrigerant. The second on-off valve 13 controls the passage and blocking of the refrigerant between the low-pressure pipe 103 and the gas pipe 106 by opening and closing. The second on-off valve 13 also has two second on-off valves 13a and 13b in accordance with the number of gas pipes 106 (indoor units 52). When the corresponding indoor unit 52 is performing cooling, it is opened to allow the refrigerant to pass therethrough, and when heating is being performed, the indoor unit 52 is closed to block the passage of the refrigerant.

  The first expansion device 14 flows out of the gas-liquid separator 11 between the first refrigerant heat exchanger 16 and the second refrigerant heat exchanger 17 and passes through the connection pipe 111 and the first refrigerant heat exchanger 16. The refrigerant (liquid refrigerant) is depressurized and flows into the second refrigerant heat exchanger 17. Further, the second expansion device 15 depressurizes a part of the refrigerant branched through the second refrigerant heat exchanger 17. Here, the first throttling device 14 and the second throttling device 15 can be configured by a flow rate control means capable of precisely controlling the flow rate by changing the opening of an electronic expansion valve or the like.

  The first refrigerant heat exchanger 16 performs heat exchange between the refrigerants. For example, heat exchange is performed between the refrigerant that has flowed out of the gas-liquid separator 11 and the refrigerant that relates to the reduced pressure that is about to flow through the second expansion device 15 and flow into the low-pressure pipe 103. The second refrigerant heat exchanger 17 also exchanges heat between the refrigerants. For example, heat exchange is performed between the refrigerant related to the reduced pressure that has passed through the first expansion device 14 and the refrigerant related to the reduced pressure that is about to flow through the second expansion device 15 and flow into the low-pressure pipe 103.

  When the refrigerant (liquid refrigerant) flows out from the gas-liquid separator 11, the bypass pipe 110 serves as a flow path that allows the refrigerant that supercools the refrigerant to pass through the low-pressure pipe 103. Further, when the refrigerant (liquid refrigerant) does not flow out from the gas-liquid separator 11, such as when all the indoor units 52 are heating, the refrigerant flowing from the liquid pipe 105 (indoor unit 52) is supplied to the low-pressure pipe 103. It becomes a flow path to flow.

[Indoor unit 52]
The configuration of the indoor unit 52 in the cooling / heating simultaneous operation type air conditioner is the same as the configuration of the indoor unit 52 of the cooling / heating switching type air conditioner. For this reason, manufacture, management, etc. can be performed in common.

  Next, the operation of the cooling and heating simultaneous operation type air conditioner will be described based on the flow of the refrigerant in the refrigerant circuit. There are four operation modes in the cooling and heating simultaneous operation type air conditioner. First, an operation in which all the indoor units 52 perform cooling (hereinafter referred to as “all cooling operation”) will be described in association with the flow of the refrigerant. Here, it is assumed that both the indoor units 52a and 52b are performing cooling.

  The high-temperature and high-pressure gas (gas) refrigerant compressed and discharged by the compressor 1 passes through the outdoor heat exchanger 2 from the four-way valve 3 and is condensed and liquefied by exchanging heat with outdoor air. Out of unit 51.

  The refrigerant flowing out of the outdoor unit 51 passes through the liquid pipe 101 and flows into the refrigerant flow control unit 53. In the refrigerant flow control unit 53, the refrigerant flows out through the connection pipe 133 (the check valve 10b). Then, it passes through the high pressure pipe 104 and flows into the repeater 54. Here, in the refrigerant flow control unit 53, the refrigerant cannot pass through the connection pipe 130 by the check valve 10 d.

  The refrigerant flowing into the relay machine 54 is separated into a gas refrigerant and a liquid refrigerant by the gas-liquid separator 11. Here, since the refrigerant flowing into the relay 54 during the cooling only operation is a liquid refrigerant, no gas refrigerant flows through the connection pipe 112.

  The liquid refrigerant that has passed through the gas-liquid separator 11 passes through the first refrigerant heat exchanger 16, the first expansion device 14, and the second refrigerant heat exchanger 17, and a part thereof is the second expansion device 15 (bypass piping 110). ) And the remainder flows out of the relay 54. At this time, the degree of supercooling is increased by the first refrigerant heat exchanger 16, the pressure is reduced to an intermediate pressure by the first expansion device 14, and the degree of supercooling is further increased by the second refrigerant heat exchanger 17.

  The liquid refrigerant flowing into the second expansion device 15 is depressurized to a low pressure, passes through the second refrigerant heat exchanger 17 and the first refrigerant heat exchanger 16, and passes through the liquid refrigerant from the gas-liquid separator 11 by heat exchange. As it cools, it evaporates and gasifies. The refrigerant that has passed through the first refrigerant heat exchanger 16 passes through the bypass pipe 110, merges with the gas refrigerant from the indoor units 52a and 52b side, and flows out from the relay unit 54.

  On the other hand, the refrigerant flowing out of the relay machine 54 passes through the liquid pipes 105a and 105b and flows into the indoor units 52a and 52b, respectively. The refrigerant that has flowed into the indoor units 52a and 52b is decompressed in the indoor expansion devices 6a and 6b, passes through the indoor heat exchangers 5a and 5b, and flows out of the indoor units 52a and 52b. At this time, in the indoor heat exchangers 5a and 5b, the refrigerant is evaporated and vaporized (gasified) by heat exchange, and for example, air in the air-conditioning target space is cooled. Thereby, the air-conditioning target space is cooled. The refrigerant that has flowed out of the indoor units 52a and 52b passes through the gas pipes 106a and 106b and flows into the relay 54.

  The refrigerant that has flowed into the relay machine 54 passes through the second on-off valve 13a and the second on-off valve 13b to join, and further joins the refrigerant that has passed through the bypass pipe 110 and flows out of the relay machine 54. The refrigerant flowing out from the relay machine 54 passes through the low pressure pipe 103 and flows into the refrigerant flow control unit 53. In the refrigerant flow control unit 53, the refrigerant flows out through the connection pipe 132 (the check valve 10a). Then, the gas passes through the gas pipe 102 and flows into the outdoor unit 51. Here, in the refrigerant flow control unit 53, since the refrigerant pressure is higher on the connection pipe 133 side, the refrigerant flowing into the refrigerant flow control unit 53 cannot pass through the check valves 10c and 10d.

  The refrigerant flowing into the outdoor unit 51 is sucked into the compressor 1 through the four-way valve 3 and the accumulator 4, and circulates by being compressed and discharged as described above.

  Next, when the indoor unit 52 that performs cooling and the indoor unit 52 that performs heating exist at the same time and the cooling load is higher than the heating load (hereinafter referred to as cooling main operation), the operation is made to correspond to the flow of the refrigerant. I will explain. Here, it is assumed that the indoor unit 52a performs heating and the indoor unit 52b performs cooling.

  The high-temperature, high-pressure gas (gas) refrigerant compressed and discharged by the compressor 1 passes through the outdoor heat exchanger 2 from the four-way valve 3 and exchanges heat with outdoor air, so that a part of the refrigerant is condensed. It liquefies and flows out of the outdoor unit 51 as a gas-liquid two-phase refrigerant. Here, the amount of refrigerant condensed and liquefied in the outdoor heat exchanger 2 (the ratio of gas refrigerant to liquid refrigerant) is determined according to the cooling load and the heating load.

  The refrigerant flowing out of the outdoor unit 51 passes through the liquid pipe 101 and flows into the refrigerant flow control unit 53. In the refrigerant flow control unit 53, the refrigerant flows out through the connection pipe 133 (the check valve 10b). Then, it passes through the high pressure pipe 104 and flows into the repeater 54.

  The refrigerant flowing into the relay machine 54 is separated into a gas refrigerant and a liquid refrigerant by the gas-liquid separator 11. The liquid refrigerant separated by the gas-liquid separator 11 passes through the first refrigerant heat exchanger 16, the first expansion device 14, and the second refrigerant heat exchanger 17, and a part thereof is the second expansion device 15 (bypass piping). 110), and the remainder flows out of the repeater 54. At this time, the degree of supercooling is increased by the first refrigerant heat exchanger 16, the pressure is reduced to an intermediate pressure by the first expansion device 14, and the degree of supercooling is further increased by the second refrigerant heat exchanger 17.

  The liquid refrigerant flowing into the second expansion device 15 is depressurized to a low pressure, passes through the second refrigerant heat exchanger 17 and the first refrigerant heat exchanger 16, and passes through the liquid refrigerant from the gas-liquid separator 11 by heat exchange. As it cools, it evaporates and gasifies. The refrigerant that has passed through the first refrigerant heat exchanger 16 passes through the bypass pipe 110, merges with the gas refrigerant from the indoor units 52a and 52b side, and flows out from the relay unit 54.

  On the other hand, the gas refrigerant separated by the gas-liquid separator 11 passes through the first on-off valve 12a and flows out from the relay unit 54. Then, the gas passes through the gas pipe 106a and flows into the indoor unit 52a. The refrigerant flowing into the indoor unit 52a passes through the indoor heat exchanger 5a. At this time, in the indoor heat exchanger 5a, the refrigerant is condensed and liquefied by heat exchange, and for example, air in the air-conditioning target space is heated. Thereby, the air-conditioning target space is heated. The refrigerant that has passed through the indoor heat exchanger 5a is depressurized by the indoor expansion device 6a to become an intermediate-pressure liquid refrigerant, flows out of the indoor unit 52a, and passes through the liquid pipe 105a.

  In addition, the refrigerant that has flowed out of the relay machine 54 merges with the refrigerant that has passed through the liquid pipe 105a, passes through 105b, and flows into the indoor unit 52b. The refrigerant flowing into the indoor unit 52b is decompressed in the indoor expansion device 6b, passes through the indoor heat exchangers 5a and 5b, and flows out of the indoor unit 52b. At this time, in the indoor heat exchanger 5b, the refrigerant is evaporated and vaporized (gasified) by heat exchange, and for example, air in the air-conditioning target space is cooled. Thereby, the air-conditioning target space is cooled. The refrigerant that has flowed out of the indoor unit 52b passes through the gas pipe 106b and flows into the relay unit 54.

  The refrigerant that has flowed into the relay machine 54 passes through the second on-off valve 13b, merges with the refrigerant that has passed through the bypass pipe 110, and flows out of the relay machine 54. The refrigerant flowing out from the relay machine 54 passes through the low pressure pipe 103 and flows into the refrigerant flow control unit 53. In the refrigerant flow control unit 53, the refrigerant flows out through the connection pipe 132 (the check valve 10a). Then, the gas passes through the gas pipe 102 and flows into the outdoor unit 51.

  The refrigerant flowing into the outdoor unit 51 is sucked into the compressor 1 through the four-way valve 3 and the accumulator 4, and circulates by being compressed and discharged as described above.

  Next, the operation when the indoor unit 52 that performs cooling and the indoor unit 52 that performs heating simultaneously exist and the heating load is higher than the cooling load (hereinafter referred to as heating-main operation) is made to correspond to the flow of the refrigerant. I will explain. Here, it is assumed that the indoor unit 52a performs heating and the indoor unit 52b performs cooling.

  The high-temperature, high-pressure gas (gas) refrigerant compressed and discharged by the compressor 1 passes through the four-way valve 3 and flows out of the outdoor unit 51.

  The refrigerant flowing out of the outdoor unit 51 passes through the gas pipe 102 and flows into the refrigerant flow control unit 53. In the refrigerant flow control unit 53, the refrigerant flows out through the connection pipe 131 (check valve 10c). Then, it passes through the high pressure pipe 104 and flows into the repeater 54. Here, in the refrigerant flow control unit 53, the refrigerant cannot pass through the low-pressure pipe 103 side by the check valve 10 a.

  The refrigerant flowing into the relay machine 54 is separated into a gas refrigerant and a liquid refrigerant by the gas-liquid separator 11. In the heating main operation, the liquid refrigerant does not flow through the connection pipe 111. The gas refrigerant that has passed through the gas-liquid separator 11 passes through the first on-off valve 12a and flows out of the repeater 54. Then, the gas passes through the gas pipe 106a and flows into the indoor unit 52a. The refrigerant flowing into the indoor unit 52a passes through the indoor heat exchanger 5a. At this time, in the indoor heat exchanger 5a, the refrigerant is condensed and liquefied by heat exchange, and for example, air in the air-conditioning target space is heated. Thereby, the air-conditioning target space is heated. The refrigerant that has passed through the indoor heat exchanger 5a is depressurized by the indoor expansion device 6a to become an intermediate-pressure liquid refrigerant, flows out of the indoor unit 52a, and passes through the liquid pipe 105a.

  Part of the refrigerant that has passed through the liquid pipe 105 a passes through the liquid pipe 105 b and flows into the indoor unit 52 b, and the rest flows into the relay unit 54. The refrigerant flowing into the relay 54 passes through the second expansion device 15, the second refrigerant heat exchanger 17, the first refrigerant heat exchanger 16, and the bypass pipe 110, and merges with the gas refrigerant from the indoor unit 52b side. It flows out from the repeater 54.

  The refrigerant flowing into the indoor unit 52b is decompressed in the indoor expansion device 6b, passes through the indoor heat exchangers 5a and 5b, and flows out of the indoor unit 52b. At this time, in the indoor heat exchanger 5b, the refrigerant is evaporated and vaporized (gasified) by heat exchange, and for example, air in the air-conditioning target space is cooled. Thereby, the air-conditioning target space is cooled. The refrigerant that has flowed out of the indoor unit 52b passes through the gas pipe 106b and flows into the relay unit 54.

  The refrigerant that has flowed into the relay machine 54 passes through the second on-off valve 13b, merges with the refrigerant that has passed through the bypass pipe 110, and flows out of the relay machine 54. The refrigerant flowing out from the relay machine 54 passes through the low pressure pipe 103 and flows into the refrigerant flow control unit 53. In the refrigerant flow control unit 53, the refrigerant flows out through the connection pipe 130 (the check valve 10d). Then, it passes through the liquid pipe 101 and flows into the outdoor unit 51.

  The refrigerant flowing into the outdoor unit 51 passes through the outdoor heat exchanger 2, evaporates and vaporizes (gasifies) by exchanging heat with outdoor air, and is further compressed through the four-way valve 3 and the accumulator 4. It is sucked into the machine 1 and circulated by being compressed and discharged as described above.

  Finally, an operation of heating all the indoor units 52 (hereinafter referred to as a heating only operation) will be described in correspondence with the flow of the refrigerant. Here, it is assumed that both the indoor units 52a and 52b are heating.

  The high-temperature, high-pressure gas (gas) refrigerant compressed and discharged by the compressor 1 passes through the four-way valve 3 and flows out of the outdoor unit 51.

  The refrigerant flowing out of the outdoor unit 51 passes through the gas pipe 102 and flows into the refrigerant flow control unit 53. In the refrigerant flow control unit 53, the refrigerant flows out through the connection pipe 131 (check valve 10c). Then, it passes through the high pressure pipe 104 and flows into the repeater 54.

  The refrigerant flowing into the relay machine 54 is separated into a gas refrigerant and a liquid refrigerant by the gas-liquid separator 11. In the all heating operation, the liquid refrigerant does not flow through the connection pipe 111. The gas refrigerant that has passed through the gas-liquid separator 11 passes through the first on-off valve 12 and flows out from the relay unit 54. Then, the gas passes through the gas pipe 106 and flows into the indoor unit 52. The refrigerant that has flowed into the indoor unit 52 passes through the indoor heat exchanger 5. At this time, in the indoor heat exchanger 5, the refrigerant is condensed and liquefied by heat exchange, and for example, air in the air-conditioning target space is heated. Thereby, the air-conditioning target space is heated. The refrigerant that has passed through the indoor heat exchanger 5a is decompressed by the indoor expansion device 6 to become liquid refrigerant, flows out of the indoor unit 52, passes through the liquid pipe 105, and flows into the relay 54.

  The refrigerant that has flowed into the relay 54 passes through the second expansion device 15, the second refrigerant heat exchanger 17, the first refrigerant heat exchanger 16, and the bypass pipe 110, and then flows out of the relay 54. The refrigerant that has flowed out passes through the low-pressure pipe 103 and flows into the refrigerant flow control unit 53. In the refrigerant flow control unit 53, the refrigerant flows out through the connection pipe 130 (the check valve 10d). Then, it passes through the liquid pipe 101 and flows into the outdoor unit 51.

  The refrigerant flowing into the outdoor unit 51 passes through the outdoor heat exchanger 2, evaporates and vaporizes (gasifies) by exchanging heat with outdoor air, and is further compressed through the four-way valve 3 and the accumulator 4. It is sucked into the machine 1 and circulated by being compressed and discharged as described above.

  As described above, according to the air conditioner of the first embodiment, the outdoor unit 51, the indoor unit 52, and the refrigerant heat exchanger unit 55 are connected to each other to form a cooling / heating switching type air conditioner. Since the combination of the indoor unit 52, the refrigerant flow control unit 53 and the relay 54 is connected by piping to form a cooling and heating simultaneous operation type air conditioner, the outdoor unit 51 and the indoor unit 52 are manufactured in common. Can be managed. For this reason, it is not necessary to divide the main equipment that constitutes the refrigerant circuit into a cooling / heating switching type air conditioner and a cooling / heating simultaneous operation type air conditioner. Productivity can be improved because there is no need to change and there is no need to provide production equipment, lines, etc. according to each type. In addition, since the outdoor unit 51 can be shared by the cooling / heating switching type air conditioning apparatus and the cooling / heating simultaneous operation type air conditioning apparatus, inventory management becomes easy. For example, it is possible to secure a storage place by overmanufacturing one mold, or to reduce the risk (risk) of running out of stock. Moreover, since it can be divided into each unit, it is possible to reduce the size and the like at the time of transportation. For example, the transportation can be facilitated at the time of assembly, disassembly and recovery. Moreover, since the combination of the refrigerant flow control unit 53 and the relay 54 or the refrigerant heat exchanger unit 55 can be easily replaced, the type of the installed air conditioner can be easily changed. Further, for example, even when the heat exchanging expansion device 6 or the like breaks down, it can be dealt with by replacing the corresponding unit such as the refrigerant heat exchanger unit 55 or the like, so that the entire device can have a long life.

Embodiment 2. FIG.
FIG. 3 is a diagram illustrating a configuration of an air-conditioning apparatus according to Embodiment 2 of the present invention. In FIG. 3, the same reference numerals as those in FIG. 1 and the like serve the same functions as those described in the first embodiment. The present embodiment is a cooling / heating switching type air conditioner having a larger number of outdoor units 51 than the refrigerant heat exchanger unit 55. In FIG. 3, two outdoor units 51 are connected in parallel with a refrigerant heat exchanger unit 55 to form a refrigerant circuit. Here, in the air conditioner of the present embodiment, in the outdoor unit 51, the outdoor expansion device 21 (21a, 21b) is provided between the outdoor heat exchanger 2 and the refrigerant heat exchanger 8 of the refrigerant heat exchanger unit 55. Is arranged.

  Here, as shown in FIG. 3, it is desirable that a plurality of outdoor units 51 are connected in parallel and further connected to one or a plurality of refrigerant heat exchanger units 55 by piping. Can achieve a certain effect. For example, the outdoor unit 51a and the refrigerant heat exchanger unit 55 are connected by piping. Then, the outdoor unit 51 b is connected by piping in the liquid piping 101 and the gas piping 102 that connect the refrigerant heat exchanger unit 55 and the indoor unit 52.

  The outdoor unit 51 has a high pressure sensor 31 on the discharge side of the compressor 1 and a low pressure sensor 32 on the suction side. The refrigerant heat exchanger unit 55 has temperature sensors 33 and 34 at portions where the refrigerant branched and passed through the heat exchange expansion device 7 flows into and out of the refrigerant heat exchanger 8, respectively. Furthermore, the indoor unit 52 has a temperature sensor 35 at the refrigerant outlet when the indoor heat exchanger 5 is in the heating operation, and has a temperature sensor 36 at the refrigerant outlet when the cooling operation is performed. Each sensor detects a physical quantity such as pressure and temperature and transmits a signal.

  Next, the flow of the refrigerant when the air-conditioning apparatus of the present embodiment performs the cooling operation will be described. For example, a high-temperature, high-pressure gas refrigerant compressed and discharged by the compressor 1a passes through the outdoor heat exchanger 2a from the four-way valve 3 and is condensed and liquefied by exchanging heat with outdoor air. And out of the outdoor unit 51a. Similarly, the refrigerant flows out in the outdoor unit 51b. The refrigerant that has flowed out of the outdoor units 51 a and 51 b joins and flows into the refrigerant heat exchanger unit 55.

  The refrigerant flow and the like in the refrigerant heat exchanger unit 55 and the indoor unit 52 are the same as those described in the first embodiment. And the refrigerant | coolant which flowed out from the refrigerant | coolant heat exchanger unit 55 branches and flows into the outdoor units 51a and 51b. The refrigerant flowing into each outdoor unit 51 passes through the outdoor heat exchanger 2, and evaporates and vaporizes by exchanging heat with, for example, outdoor air. Thereafter, the refrigerant is sucked into the compressor 1 through the four-way valve 2 and the accumulator 4, and circulated by being compressed and discharged as described above.

  Moreover, when performing heating operation, the amount of the refrigerant flowing out of the refrigerant heat exchanger unit 55 flows into the outdoor units 51a and 51b is controlled by controlling the opening degree of the outdoor expansion devices 21a and 21b, respectively. Can do. For this reason, when connecting the some compressor 1 in parallel, it is better to provide the outdoor expansion device 21. FIG. The same applies to the cooling and heating simultaneous operation type air conditioner.

  FIG. 4 is a diagram illustrating the relationship of devices related to control in the air-conditioning apparatus of the present embodiment. The outdoor units 51a and 51b have outdoor side controllers 201a and 201b shown in FIG. 4, respectively. The refrigerant heat exchanger unit 55 has a refrigerant heat exchanger controller 202. The indoor unit 52 has an indoor controller 203. In this embodiment, it is assumed that each controller is connected by a communication line and can perform signal communication. Here, description will be made assuming that the outdoor controller 201a is a main controller that controls the entire air conditioner. And the outdoor side controller 201a shall have a timer (not shown) for measuring time.

  The outdoor controller 201a is supplied with a signal of pressure Pd_a from the high pressure sensor 31a and a signal of pressure Ps_a from the low pressure sensor 32a. Similarly, the outdoor controller 201b also sends a signal of pressure Pd_b from the high pressure sensor 31b and a signal of pressure Ps_b from the low pressure sensor 32b. And the outdoor side controller 201b sends the signal of pressure Pd_b and pressure Ps_b to the outdoor side controller 201a. Further, signals of temperatures T33 and T34 are sent from the temperature sensors 33 and 34 to the refrigerant heat exchanger controller 202, respectively. Then, the refrigerant heat exchanger controller 202 sends signals of temperatures T33 and T34 to the outdoor controller 201a. Further, signals of temperatures T35 and T36 are sent from the temperature sensors 35 and 36 to the indoor controller 203, respectively.

  The outdoor side controller 201a calculates the operating frequency of the compressors 1a and 1b, the heat exchange capacity of the outdoor heat exchangers 2a and 2b, and the opening degree of the heat exchange expansion device 7 based on these data. And based on a calculation, the operating frequency of the compressor 1a of the outdoor unit 51a and the heat exchange capacity of the outdoor heat exchanger 2a are controlled. On the other hand, for the operating frequency of the compressor 1b and the heat exchange capacity of the outdoor heat exchanger 2b related to the outdoor unit 51b that is not controlled, a signal including data based on the calculation is transmitted to the outdoor controller 201b. Also for the refrigerant heat exchanger unit 55 that is not the control target, a signal including the opening degree data of the heat exchange expansion device 7 is transmitted to the refrigerant heat exchanger controller 202.

  Based on the signal from the outdoor controller 201a, the outdoor controller 201b controls the operating frequency of the compressor 1b of the outdoor unit 51b and the heat exchange capacity of the outdoor heat exchanger 2b. The refrigerant heat exchanger controller 202 controls the opening degree of the heat exchange expansion device 7. Here, the refrigerant heat exchanger controller 202 performs control based on the opening degree of the heat exchange expansion device 7 calculated by the outdoor controller 201a, but the refrigerant heat exchanger controller 202 performs calculation. The opening degree of the heat exchange expansion device 7 may be controlled.

  The indoor side controller 203 calculates the opening degree of the indoor expansion device 6 based on the temperatures T35 and T36, and controls the indoor expansion device 6.

  FIG. 5 is a flowchart illustrating a process for determining the operating frequency F in the compressor 1 of the outdoor unit 51 and the heat exchange capacity AK of the outdoor heat exchanger 2. A process performed by the outdoor controller 201a will be described with reference to FIG. For example, when a command signal for cooling or heating is sent from one or a plurality of indoor units 52, the outdoor controller 201a causes the outdoor unit 51a to start an operation related to the operation, for example. At this time, the operation is set to be controlled based on a predetermined operation frequency F and heat exchange capacity AK. Moreover, the outdoor side controller 201a starts time measurement by a timer.

  In STEP1, based on the timer, it is determined whether the time from the start of operation has passed a predetermined time tm. If it is determined that the predetermined time tm has elapsed, the process proceeds to STEP2. In STEP 2, the timer time is reset to zero.

  In STEP 3, the high pressure Pd is determined based on the signal from the high pressure sensor 31. Here, when both the outdoor units 51a and 51b are operating, the high pressure Pd is determined using the average value, maximum value, minimum value, and the like of the pressures Pd_a and Pd_b as representative values. In STEP 4, the low pressure Ps is determined based on the signal from the low pressure sensor 32. Here, when both the outdoor units 51a and 51b are operating, the low pressure Ps is determined using the average value, maximum value, minimum value, and the like of the pressures Ps_a and Ps_b as representative values.

In STEP 5, a difference ΔPd between the high pressure Pd and the target value Pdm of the high pressure is calculated. In STEP 6, the difference ΔPs between the low pressure Ps and the target value Psm of the low pressure is calculated. In STEP 7, based on the difference ΔPd and the difference ΔPs, the correction value ΔF of the operating frequency of the compressor 1 and the correction value ΔAK of the heat exchange capacity of the outdoor heat exchanger 2 are based on the following expressions (1) and (2). To calculate. The coefficients a, b, c, and d used in this calculation are determined in advance by a test or the like.
ΔF = a · ΔPd + b · ΔPs (1)
ΔAK = c · ΔPd + d · ΔPs (2)

  In STEP 8, the calculated correction value ΔF is added to the currently set operating frequency F to set it as a new operating frequency F. Further, the calculated correction value ΔAK is added to the currently set heat exchange capacity AK to set a new heat exchange capacity AK.

  In STEP 9, it is determined whether or not the new operating frequency F exceeds the upper limit value F1max of the operating frequency F of the compressor 1 in one outdoor unit 51. If it is determined that it has exceeded, the operation proceeds to STEP 10 in order to cause the plurality of outdoor units 51 to perform the operation, and if it is determined that it does not exceed, the operation proceeds to STEP 11.

  In STEP 10, based on the new operation frequency F and the outdoor heat exchanger AK, the operation frequencies Fa and Fb of the compressors 1a and 1b and the heat exchange capacities AKa and AKb of the outdoor heat exchangers 2a and 2b are calculated. To do. For example, in this embodiment, it is equally divided as Fa = Fb = F / 2 and AKa = AKb = AK / 2. However, it is not limited to equal division, and when the discharge capacity or the like of the compressor 1 in the outdoor unit 51 is different, it may be apportioned according to the discharge capacity.

  In STEP 11, since the heat quantity for the load can be supplied even when the outdoor unit 51a is operated, Fa = F, Fb = 0, AKa = AK, and AKb = 0.

  In STEP 12, it is determined whether or not to end the operation. If it is determined that the process is to be ended, the process proceeds to STEP 13 and the compressor 1 and the like of the outdoor unit 51 are stopped. If it is determined that the process does not end, the process returns to STEP 1 and the above process is repeated every time the predetermined time tm elapses.

  Here, in STEP10 mentioned above, although the outdoor unit 51a was operated, it is not limited to this. For example, in order to eliminate unevenness in operation time and to make the lifetime uniform, for example, the outdoor unit 51 to be operated by one unit is appropriately changed according to the timing such as the elapse of a predetermined time, the implementation of defrosting, and the operation is temporarily stopped. You may do it.

  FIG. 6 is a flowchart illustrating a process for determining the opening degree LEV7 of the heat exchange expansion device 7 of the refrigerant heat exchanger unit 55. A process performed by the outdoor controller 201a will be described with reference to FIG.

  In STEP 21, based on the timer, it is determined whether or not a predetermined time tm1 has elapsed from the start of operation. If it is determined that the predetermined time tm1 has elapsed, the process proceeds to STEP22. In STEP 22, the timer time is reset to zero.

  In STEP23, the temperatures T33 and T34 are detected based on the signal sent from the refrigerant heat exchanger controller 202. In STEP 24, a temperature difference SHb between the temperature T33 representing the refrigerant saturation temperature and T34 representing the refrigerant (gas refrigerant) temperature is calculated. In STEP 25, a difference ΔSHb between the temperature difference SHb and the target value SHbm is calculated. In STEP 26, for example, the coefficient k1 is multiplied by the difference ΔSHb to calculate the correction value ΔLEV7 of the opening degree of the heat exchange expansion device 7. Here, k1 is determined in advance by a test or the like. In STEP 27, the calculated correction value ΔLEV7 is added to the currently set opening degree LEV7 to set the opening degree LEV7 of the new heat exchange expansion device 7.

  In STEP 28, it is determined whether or not to end the operation. If it is determined that the process is to be ended, the process proceeds to STEP 29, and for example, the process is ended by preventing the refrigerant from passing through the heat exchange expansion device 7. If it is determined not to end, the process returns to STEP 21 and the above process is repeated every time the predetermined time tm1 elapses.

  FIG. 7 is a flowchart illustrating a process for determining the opening degree LEV6 of the indoor expansion device 6 of the indoor unit 52. A process performed by the indoor controller 203 will be described with reference to FIG.

  In STEP 31, it is determined whether or not the time from the start of operation has passed a predetermined time tm2 based on a timer. If it is determined that the predetermined time tm2 has elapsed, the process proceeds to STEP32. In STEP 32, the timer time is reset to zero.

  In STEP 33, the temperatures T35 and T36 are detected based on the signals sent from the temperature sensors 35 and 36. In STEP 34, a temperature difference SH between a temperature T35 representing the saturation temperature of the refrigerant and T36 representing the temperature of the refrigerant (gas refrigerant) is calculated. In STEP 35, a difference ΔSH between the temperature difference SH and the target value SHm is calculated. In STEP 36, for example, a coefficient k2 is multiplied by the difference ΔSH to calculate a correction value ΔLEV6 of the opening degree of the indoor expansion device 6. Here, k2 is determined in advance by a test or the like. In STEP 37, the calculated correction value ΔLEV6 is added to the currently set opening degree LEV6 to set the opening degree LEV6 of the new indoor expansion device 6.

  In STEP 38, it is determined whether or not to end the operation. If it is determined that the process is to be ended, the process proceeds to STEP 39, and for example, the process is ended by preventing the refrigerant from passing through the heat exchange expansion device 7. If it is determined not to end, the process returns to STEP 31, and the above-described processing is repeated every time the predetermined time tm2 elapses.

  As described above, according to the air conditioning apparatus of the second embodiment, the refrigerant that has flowed out of the plurality of outdoor units 51 can be supercooled in the refrigerant heat exchanger unit 55 that has fewer units than the outdoor units 51. Therefore, generation of refrigerant noise can be suppressed with an inexpensive system. Moreover, the flow controllability in the indoor expansion device 6 can be improved by expanding the range of the degree of supercooling of the refrigerant.

  Here, in the present embodiment, two outdoor units 51 are connected in parallel to one refrigerant heat exchanger unit 55 to configure a cooling / heating switching type air conditioner. However, the present invention is not limited to this. Not what you want. For example, even in the case where the outdoor unit 51 having a larger number than the refrigerant heat exchanger unit 55 is connected in parallel to the refrigerant heat exchanger unit 55 in which a plurality of units are piped in parallel, the present embodiment is used. The described effect can be achieved.

Embodiment 3 FIG.
FIG. 8 is a diagram illustrating a configuration of an air-conditioning apparatus according to Embodiment 3 of the present invention. In FIG. 8, the same reference numerals as those in FIG. 1 and the like serve the same functions as those described in the first embodiment. The present embodiment is a cooling / heating switching type air conditioner having a larger number of refrigerant heat exchanger units 55 than the number of outdoor units 51. In FIG. 8, two refrigerant heat exchanger units 55 are connected in parallel to the outdoor unit 51 to form a refrigerant circuit.

  Next, the operation of the refrigerant in the cooling operation in the cooling / heating switching type air conditioner of FIG. 8 will be described. The high-temperature and high-pressure gas refrigerant compressed and discharged by the compressor 1 passes through the outdoor heat exchanger 2 from the four-way valve 3 and is condensed and liquefied by exchanging heat with outdoor air. It flows out of the outdoor unit 51. The refrigerant flowing out of the outdoor unit 51 branches and flows into the refrigerant heat exchanger units 55a and 55b, respectively.

  The refrigerant that has flowed into the refrigerant heat exchanger units 55a and 55b passes through the refrigerant heat exchangers 8a and 8b, and then partially branches by the branch pipes and passes through the heat exchange expansion devices 7a and 7b. At this time, the refrigerant is decompressed. The decompressed refrigerant passes through the refrigerant heat exchangers 8a and 8b, and cools the refrigerant flowing from the outdoor unit 51 by heat exchange. Thereby, the supercooling degree of the refrigerant | coolant which flows out out of the refrigerant | coolant heat exchanger units 55a and 55b increases. The refrigerant that has flowed out of the refrigerant heat exchanger units 55 a and 55 b joins again, passes through the liquid pipe 101, and flows into the indoor unit 52.

  The refrigerant flowing into the indoor unit 52 is depressurized by the indoor expansion device 6, passes through the indoor heat exchanger 5, and flows out of the indoor unit 52. At this time, in the indoor heat exchanger 5, the refrigerant is evaporated and vaporized (gasified) by heat exchange, and for example, air in the air-conditioning target space is cooled. Thereby, the air-conditioning target space is cooled.

  The refrigerant flowing out of the indoor unit 52 passes through the gas pipe 102, branches again, and flows into the refrigerant heat exchanger units 55a and 55b. The refrigerant that has flowed into the refrigerant heat exchanger units 55a and 55b merges with the refrigerant that has flowed from the check valves 9a and 9b, respectively, and flows out. The refrigerant that has flowed out joins and flows into the outdoor unit 51. The refrigerant flowing into the outdoor unit 51 is sucked into the compressor 1 through the four-way valve 3 and the accumulator 4, and circulates by being compressed and discharged as described above. Here, in the present embodiment, the refrigerant that has passed through the gas pipe 102 is branched to the refrigerant heat exchanger units 55a and 55b. For example, the refrigerant heat exchanger unit 55b is not connected to the gas pipe 102 and is branched. You may make it not.

  FIG. 9 is a diagram illustrating the relationship of devices related to control in the air-conditioning apparatus of the present embodiment. The outdoor unit 51 has an outdoor controller 201. The refrigerant heat exchanger units 55a and 55b have refrigerant heat exchanger controllers 202a and 202b, respectively. The indoor unit 52 has an indoor controller 203. It is assumed that signal communication can be performed by connecting each controller with a communication line.

  The outdoor controller 201 is supplied with a high pressure Pd signal from the high pressure sensor 31 and a low pressure Ps signal from the low pressure sensor 32. Signals of temperatures T33_a and T34_a are respectively sent from the temperature sensors 33a and 34a to the refrigerant heat exchanger controller 202a. Then, the refrigerant heat exchanger controller 202a transmits the signals of the temperatures T33_a and T34_a to the outdoor controller 201. Similarly, the refrigerant heat exchanger controller 202b receives signals of temperatures T33_b and T34_b from the temperature sensors 33b and 34b, respectively. Then, the refrigerant heat exchanger controller 202b transmits signals of the temperatures T33_b and T34_b to the outdoor controller 201a. Further, signals of temperatures T35 and T36 are sent from the temperature sensors 35 and 36 to the indoor controller 203, respectively.

  The outdoor side controller 201 calculates the operating frequency of the compressor 1, the heat exchange capacity of the outdoor heat exchanger 2, and the opening degree of the heat exchange expansion devices 7a and 7b based on these data. Based on the calculation, the operation frequency of the compressor 1 of the outdoor unit 51 and the heat exchange capacity of the outdoor heat exchanger 2 are controlled. On the other hand, for the refrigerant heat exchanger units 55a and 55b that are not controlled, signals including the opening degree data of the heat exchange expansion devices 7a and 7b are transmitted to the refrigerant heat exchanger controllers 202a and 202b, respectively. The refrigerant heat exchanger controllers 202a and 202b control the opening degree of the heat exchange expansion devices 7a and 7b, respectively.

  The indoor side controller 203 calculates the opening degree of the indoor expansion device 6 based on the temperatures T35 and T36, and controls the indoor expansion device 6.

  FIG. 10 is a flowchart illustrating a process for determining the operating frequency F in the compressor 1 of the outdoor unit 51 and the heat exchange capacity AK of the outdoor heat exchanger 2. A process performed by the outdoor controller 201 will be described with reference to FIG. For example, when a command signal for cooling or heating is sent from one or a plurality of indoor units 52, the outdoor controller 201 causes the outdoor unit 51 to start an operation related to the operation, for example. At this time, the operation is set to be controlled based on a predetermined operation frequency F and heat exchange capacity AK. Moreover, the outdoor side controller 201 starts time measurement by a timer.

  In STEP 41, based on the timer, it is determined whether the time from the start of operation has passed a predetermined time tm. If it is determined that the predetermined time tm has elapsed, the process proceeds to STEP42. In STEP 42, the timer time is reset to zero.

  In STEP 43, the high pressure Pd is determined based on the signal from the high pressure sensor 31. In STEP 44, the low pressure Ps is determined based on the signal from the low pressure sensor 32.

  In STEP 45, a difference ΔPd between the high pressure Pd and the target value Pdm of the high pressure is calculated. In STEP 46, the difference ΔPs between the low pressure Ps and the target value Psm of the low pressure is calculated. In STEP 47, the correction value ΔF of the operating frequency of the compressor 1 and the correction value ΔAK of the heat exchange capacity of the outdoor heat exchanger 2 are described in the second embodiment based on the difference ΔPd and the difference ΔPs (1). , (2) is calculated based on the equation.

  In STEP 48, the calculated correction value ΔF is added to the currently set operating frequency F to set it as a new operating frequency F. Further, the calculated correction value ΔAK is added to the currently set heat exchange capacity AK to set a new heat exchange capacity AK.

  In STEP 49, it is determined whether or not to end the operation. If it is determined that the process is to be ended, the process proceeds to STEP 50, and the compressor 1 and the like of the outdoor unit 51 are stopped. If it is determined that the process is not finished, the process returns to STEP 41 and the above process is repeated every time the predetermined time tm elapses.

  FIG. 11 is a flowchart illustrating a process for determining the opening degree LEV7 of the heat exchange expansion device 7 of the refrigerant heat exchanger unit 55. A process performed by the outdoor controller 201 will be described with reference to FIG.

  In STEP 51, based on the timer, it is determined whether or not a predetermined time tm1 has elapsed from the start of operation. If it is determined that the predetermined time tm1 has elapsed, the process proceeds to STEP52. In STEP 52, the timer time is reset to zero.

  In STEP 53, the temperatures T33_a, T34_a, T33_b, and T34_b are detected based on signals sent from the refrigerant heat exchanger controllers 202a and 202b. In STEP54, the temperature difference SHb1 between the temperatures T33_a and T34_a and the temperature difference SHb2 between the temperatures T33_b and T34_b are calculated. In STEP55, a difference ΔSHb1 between the temperature difference SHb1 and the target value SHbm and a difference ΔSHb2 between the temperature difference SHb2 and the target value SHbm are calculated. In STEP 56, for example, the coefficient Δk1 is multiplied by the difference ΔSHb1 to calculate the correction value ΔLEV7a of the opening degree of the heat exchange expansion device 7a. Further, the correction value ΔLEV7b of the opening degree of the heat exchange expansion device 7b is calculated by multiplying the difference kSH2 by the coefficient k1. Here, k1 is determined in advance by a test or the like. In STEP57, the calculated correction value ΔLEV7a is added to the currently set opening degree LEV7a to set the opening degree LEV7a of the new heat exchange expansion device 7a. Similarly, the calculated correction value ΔLEV7b is added to the currently set opening degree LEV7b to set the opening degree LEV7b of the new heat exchange expansion device 7b.

  In STEP 58, it is determined whether or not to end the operation. If it is determined that the process is to be terminated, the process proceeds to STEP 59, and the process is terminated by preventing the refrigerant from passing through, for example, the heat exchange expansion devices 7a and 7b. If it is determined that the process does not end, the process returns to STEP 51 and the above process is repeated every time the predetermined time tm1 elapses.

  The process of determining the opening degree LEV6 of the indoor expansion device 6 of the indoor unit 52 performed by the indoor controller 203 is the same as the procedure described in the second embodiment.

  As described above, according to the air conditioning apparatus of the third embodiment, the refrigerant that has flowed out of the outdoor unit 51 can be supercooled in the refrigerant heat exchanger unit 55 that has more units than the outdoor unit 51. The generation of refrigerant noise can be suppressed with a simple system. Moreover, since the range of the degree of supercooling of the refrigerant can be expanded, the flow controllability in the indoor expansion device 6 can be improved.

  Here, in the present embodiment, two refrigerant heat exchanger units 55 are connected in parallel to one outdoor unit 51 to configure a cooling / heating switching type air conditioner. However, the present invention is limited to this. Not what you want. For example, even when the refrigerant heat exchanger unit 55 having a larger number than the outdoor unit 51 is configured by pipe connection in parallel, the effects described in the present embodiment can be achieved. Further, the refrigerant heat exchanger unit 55 may be configured by pipe connection in series.

Embodiment 4 FIG.
FIG. 12 is a diagram illustrating a configuration of an air-conditioning apparatus according to Embodiment 4 of the present invention. In FIG. 12, the same reference numerals as those in FIG. 2 and the like serve the same functions as those described in the first embodiment. The present embodiment is a cooling and heating simultaneous operation type air conditioner having a larger number of refrigerant flow control units 53 than the outdoor unit 51. In FIG. 12, two refrigerant flow control units 53 (53a, 53b) are connected in parallel between the outdoor unit 51 and the relay 54 to constitute a refrigerant circuit.

  Here, the check valves 10e, 10f, 10g, and 10h in the refrigerant flow control unit 53b correspond to the check valves 10a, 10b, 10c, and 10d in the refrigerant flow control unit 53a, respectively.

  Next, the operation of the cooling and heating simultaneous operation type air conditioner will be described. The operations and the like in the outdoor unit 51, the repeater 54, and the indoor unit 52 are the same as those described in the first embodiment. Here, the flow of the refrigerant in the refrigerant flow control units 53a and 53b will be described.

  The refrigerant flow in the refrigerant flow control unit 53 during the cooling only operation and the cooling main operation will be described. The high-pressure refrigerant (liquid refrigerant) flowing out of the outdoor unit 51 branches through the liquid pipe 101 and flows into the refrigerant flow control units 53a and 53b, respectively. In the refrigerant flow control unit 53a, the refrigerant flows out through the connection pipe 133a (the check valve 10b). Further, in the refrigerant flow control unit 53b, the refrigerant flows out through the connection pipe 133b (the check valve 10e). Then, the refrigerants flowing out from the refrigerant flow control units 53a and 53b merge and pass through the high-pressure pipe 104 and flow into the relay unit 54.

  On the other hand, the refrigerant that has flowed out of the relay machine 54 branches through the low-pressure pipe 103 and flows into the refrigerant flow control units 53a and 53b, respectively. In the refrigerant flow control unit 53a, the refrigerant flows out through the connection pipe 132a (the check valve 10a). In the refrigerant flow control unit 53b, the refrigerant flows out through the connection pipe 132b (the check valve 10a). Then, the refrigerants flowing out from the refrigerant flow control units 53a and 53b merge, pass through the gas pipe 102, and flow into the outdoor unit 51.

  The refrigerant flow in the refrigerant flow control unit 53 during the all heating operation and the heating main operation will be described. The high-pressure refrigerant (gas refrigerant) flowing out of the outdoor unit 51 branches through the gas pipe 102 and flows into the refrigerant flow control units 53a and 53b, respectively. In the refrigerant flow control unit 53a, the refrigerant flows out through the connection pipe 131a (the check valve 10c). In the refrigerant flow control unit 53b, the refrigerant flows out through the connection pipe 131b (the check valve 10g). Then, the refrigerants flowing out from the refrigerant flow control units 53a and 53b merge and pass through the high-pressure pipe 104 and flow into the relay unit 54.

  On the other hand, the refrigerant that has flowed out of the relay machine 54 branches through the low-pressure pipe 103 and flows into the refrigerant flow control units 53a and 53b, respectively. In the refrigerant flow control unit 53a, the refrigerant flows out through the connection pipe 130a (the check valve 10d). In the refrigerant flow control unit 53b, the refrigerant flows out through the connection pipe 130b (check valve 10h). Then, the refrigerants flowing out from the refrigerant flow control units 53a and 53b merge, pass through the gas pipe 102, and flow into the outdoor unit 51.

  As described above, according to the air conditioning apparatus of the fourth embodiment, since the refrigerant is allowed to pass through the plurality of refrigerant flow control units 53 (53a, 53b) connected in parallel with each other, pressure loss can be suppressed. And efficient operation can be performed.

  Here, in the present embodiment, two refrigerant flow control units 53 are connected in parallel to one outdoor unit 51 to configure a cooling and heating simultaneous operation type air conditioner. However, the present invention is limited to this. Not what you want. For example, even when the refrigerant flow control units 53 that are larger in number than the outdoor units 51 are configured by pipe connection in parallel, the effects described in the present embodiment can be achieved.

Embodiment 5 FIG.
FIG. 13 is a diagram illustrating a configuration of an air-conditioning apparatus according to Embodiment 5 of the present invention. In FIG. 13, the means and the like with the same reference numerals as those in FIG. 2 perform the same functions as those described in the first embodiment. In the present embodiment, the outdoor unit 51 and the refrigerant flow control unit 53 are connected by a liquid pipe 101a and a gas pipe 102a which are refrigerant pipes. Further, the refrigerant flow control unit 53 and the relay 54 are connected by a low pressure pipe 103a and a high pressure pipe 104a which are refrigerant pipes. And the length of the liquid piping 101a and the gas piping 102a is made longer than the low pressure pipe 103a and the high pressure pipe 104a, respectively. Further, the pipe diameter of the gas pipe 102a is made larger than the pipe diameter of the liquid pipe 101a (the gas pipe 102a is made thicker than the liquid pipe 101a).

  The operation and the like of the air conditioner in the present embodiment are the same as the operation and the like of the cooling and heating simultaneous operation type air conditioner described in the first embodiment. Instead of the refrigerant passing through the liquid pipe 101 in the first embodiment, the refrigerant passes through the liquid pipe 101a in the present embodiment. In the first embodiment, the refrigerant passes through the gas pipe 102a in this embodiment instead of passing through the gas pipe 102. Furthermore, instead of the refrigerant passing through the low-pressure pipe 103 in the first embodiment, in this embodiment, the refrigerant passes through the low-pressure pipe 103a. In the first embodiment, the refrigerant passes through the high pressure pipe 104a in this embodiment instead of passing through the high pressure pipe 104.

  For example, since the gas refrigerant is more affected by the pressure loss due to the size of the pipe diameter than the liquid refrigerant, the pipe through which the gas refrigerant passes should be thicker than the pipe through which the liquid refrigerant passes. Further, if the liquid refrigerant returns too much to the outdoor unit 51 side, the amount of liquid back to the compressor 1 may increase when the refrigerant flow changes, so the pipe diameter through which the liquid refrigerant passes is moderately large. Is good. Here, in the cooling and heating simultaneous operation type air conditioner, both the gas refrigerant and the liquid refrigerant can pass through the high-pressure pipe and the low-pressure pipe for allowing the refrigerant to flow into and out of the relay unit 54. It is difficult to adopt a configuration. For this reason, when the high-pressure pipe 104a and the low-pressure pipe 103a become longer, the pressure loss increases accordingly.

  Therefore, in the air conditioning apparatus of the present embodiment, the gas pipe 102a through which only the gas refrigerant passes is made thicker than the liquid pipe 101a through which the liquid refrigerant passes. In addition, the gas pipe 102a and the liquid pipe 101a are configured to be longer than the low pressure pipe 103a and the high pressure pipe 104a.

  As described above, according to the air conditioner of the fifth embodiment, the pipes connected to the refrigerant flow control unit 53 are configured such that the gas pipe 102a and the liquid pipe 101a have different pipe diameters, and the gas pipe 102a and the liquid pipe 101a are connected. Since it is configured to be longer than the low-pressure pipe 103a and the high-pressure pipe 104a, the pressure loss can be reduced, and the amount of temporary liquid back during stoppage or operation mode change can be suppressed. Can be configured.

  DESCRIPTION OF SYMBOLS 1 Compressor, 2 Outdoor heat exchanger, 3 Four way valve, 4 Accumulator, 5, 5a, 5b Indoor heat exchanger, 6, 6a, 6b Indoor expansion device, 7, 7a, 7b Heat exchange expansion device, 8, 8a, 8b Refrigerant heat exchanger, 9, 9a, 9b Check valve, 10, 10a, 10b, 10c, 10d, 10e, 10f, 10g, 10h Check valve, 11 Gas-liquid separator, 12, 12a, 12b First open / close Valve, 13, 13a, 13b second on-off valve, 14 first throttle device, 15 second throttle device, 16 first refrigerant heat exchanger, 17 second refrigerant heat exchanger, 21, 21a, 21b outdoor throttle device, 31 , 31a, 31b High pressure sensor, 32, 32a, 32b Low pressure sensor, 33, 33a, 33b, 34, 34a, 34b, 35, 36 Temperature sensor, 51, 51a, 51b Outdoor unit, 52 52a, 52b Indoor unit, 53, 53a, 53b Refrigerant flow control unit, 54 Relay machine, 55, 55a, 55b Refrigerant heat exchanger unit, 101, 101a Liquid pipe, 102, 102a Gas pipe, 103, 103a Low pressure pipe, 104 104a High pressure pipe, 105, 105a, 105b Liquid pipe, 106, 106a, 106b Gas pipe, 110 Bypass pipe, 111, 112, 130, 131, 132, 133 Connection pipe, 201, 201a, 201b Outdoor controller, 202 202a, 202b Refrigerant heat exchanger controller, 203 indoor controller, a, b, c, d.

Claims (5)

A compressor that compresses and discharges the refrigerant, a heat source machine side heat exchanger that exchanges heat between the outside air and the refrigerant, and an outdoor unit that has a four-way valve for switching the flow path of the refrigerant;
An indoor unit having an indoor heat exchanger for exchanging heat between air to be air-conditioned and a refrigerant and an indoor expansion device for depressurizing the refrigerant;
A heat exchange throttle device that decompresses a part of the refrigerant flowing from the outdoor unit, and a refrigerant heat exchanger that supercools the refrigerant flowing from the outdoor unit side to the indoor unit side by heat exchange with the refrigerant that has passed through the heat exchange throttle device A refrigerant heat exchanger unit, or a relay that forms a flow path for supplying a gaseous refrigerant to the indoor unit for heating and supplying a liquid refrigerant to the indoor unit for cooling, and Either one of the combinations of the refrigerant flow control unit that controls the flow of the refrigerant between the outdoor unit and the relay unit is used as a refrigerant pipe that forms two flow paths between the outdoor unit and the indoor unit. An air conditioner that is connected to form a refrigerant circuit.   More than the number of the refrigerant heat exchanger units or the refrigerant flow control units are arranged in parallel to the refrigerant heat exchanger unit or the refrigerant flow control unit in which one or more pipes are connected in parallel. 2. An air conditioner according to claim 1, wherein the air conditioner is connected to a pipe.   2. The configuration according to claim 1, wherein the number of the refrigerant heat exchanger units that are larger than the number of the outdoor units is piped to the outdoor unit in which one or a plurality of pipes are connected in parallel. Air conditioner.   2. A configuration in which a greater number of the refrigerant flow control units than the number of the outdoor units is connected in parallel to the outdoor unit in which one or a plurality of units are connected in parallel by piping. Air conditioner.   The length of the refrigerant pipe that connects the outdoor unit and the refrigerant flow control unit is longer than the length of the refrigerant pipe that connects the refrigerant flow control unit and the relay. Item 5. The air conditioner according to Item 1 or 4.

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