Air conditioning device

Abstract

This air conditioning device comprises a refrigerant circuit which has five or more heat exchangers and in which a refrigerant circulates. The refrigerant circuit has: a first branch part composed of a first two-branch pipe; a first flow rate adjustment valve provided to one of two pipes branching from the first branch part, and a second flow rate adjustment valve provided to the other pipe; a second branch part composed of one or more second two-branch pipes; and a third branch part composed of one or more third two-branch pipes. The five or more heat exchangers are divided into a first group and a second group so that heat exchangers having the same heat exchange capacity are in the same group. The first group is connected downstream from the first flow rate adjustment valve and the second group is connected downstream from the second flow rate adjustment valve. The refrigerant flowing out from the first flow rate adjustment valve is distributed by the second branch part to each of the heat exchangers belonging to the first group in parallel, and the refrigerant flowing out from the second flow rate adjustment valve is distributed by the third branch part to each of the heat exchangers belonging to the second group in parallel.

Description

air conditioning equipment

[0001] The present disclosure relates to an air conditioner including a plurality of heat exchangers through which a refrigerant flows in parallel.

[0002] Conventionally, there is an air conditioner equipped with a plurality of heat exchangers through which a refrigerant is distributed and flows in parallel (see, for example, Patent Document 1). The air conditioner in Patent Document 1 discloses a configuration in which a plurality of heat exchangers are provided in a housing that constitutes an outdoor unit, and a refrigerant flows in parallel through each of the plurality of heat exchangers.

[0003] International Publication No. 2022 / 249425

[0004] To realize an air conditioner with a high air conditioning capacity, the number of heat exchangers needs to be increased. However, as the number of heat exchangers increases, it becomes difficult to optimally distribute the refrigerant while taking into account the heat exchange capacity of each heat exchanger. One possible method for achieving optimal refrigerant distribution while taking into account the heat exchange capacity is to provide a flow control valve for each heat exchanger. However, this method requires a flow control valve for each heat exchanger, resulting in high costs.

[0005] The air conditioning apparatus of Patent Document 1 discloses a configuration in which the number of flow control valves is less than the number of heat exchangers, but does not consider optimal flow distribution of refrigerant to each heat exchanger.

[0006] The present disclosure is intended to solve the above-mentioned problems, and aims to provide an air conditioning apparatus that can achieve optimal flow distribution of refrigerant at low cost while reducing the number of flow control valves.

[0007] The air conditioning apparatus according to the present disclosure has five or more heat exchangers and is provided with a refrigerant circuit through which a refrigerant circulates, the refrigerant circuit having a first branch section made up of a first two-branch pipe, a first flow rate adjustment valve provided on one of two pipes branched from the first branch section and a second flow rate adjustment valve provided on the other, a second branch section made up of one or more second two-branch pipes, and a third branch section made up of one or more third two-branch pipes, and the five or more heat exchangers are divided into first and second groups so that heat exchangers with the same heat exchange capacity are in the same group. The first group is connected downstream of the first flow control valve, the second group is connected downstream of the second flow control valve, a second branch section is provided between the first flow control valve and the first group, and the refrigerant flowing out from the first flow control valve is distributed in parallel to each of the plurality of heat exchangers belonging to the first group, and a third branch section is provided between the second flow control valve and the second group, and the refrigerant flowing out from the second flow control valve is distributed in parallel to each of the plurality of heat exchangers belonging to the second group.

[0008] The air conditioning apparatus according to the present disclosure has a refrigerant circuit having five or more heat exchangers and through which a refrigerant circulates, the refrigerant circuit having a first branch section made up of a first two-branch pipe, a first flow rate adjustment valve provided on one of two pipes branched off from the first branch section and a second flow rate adjustment valve provided on the other, a second branch section made up of one or more second two-branch pipes, and a third branch section made up of one or more third two-branch pipes, the five or more heat exchangers being three types of heat exchangers with different heat exchange capacities, divided into a first group and a second group so that heat exchangers with the same heat exchange capacity are in the same group, the first group is connected downstream of the first flow rate adjustment valve, and the second group is connected downstream of the second flow rate adjustment valve. a second branch section provided between the first flow control valve and the first group, such that the refrigerant flowing out from the first flow control valve is distributed in parallel to each of the plurality of heat exchangers belonging to the first group; a third branch section provided between the second flow control valve and the second group, such that the refrigerant flowing out from the second flow control valve is distributed in parallel to each of the plurality of heat exchangers belonging to the second group; the plurality of heat exchangers belonging to at least one of the first group and the second group have the configuration (1), and the plurality of heat exchangers belonging to other than at least one of the first group and the second group have the configuration (1) or (2). (1) The refrigerant is divided into a first subgroup and a second subgroup, such that the refrigerant branched into two is distributed and flows through the first subgroup and the second subgroup, and the total refrigerant pressure loss of the first subgroup and the total refrigerant pressure loss of the second subgroup are set to be the same; and (2) the heat exchange capacities are set to be the same.

[0009] The air conditioning apparatus according to the present disclosure has five or more heat exchangers and is provided with a refrigerant circuit through which a refrigerant circulates, the refrigerant circuit having a first branch section made up of a first two-branch pipe, a first flow rate adjustment valve provided in one of two pipes branched at the first branch section and a second flow rate adjustment valve provided in the other, a second branch section made up of one or more second two-branch pipes, a third branch section made up of one or more third two-branch pipes, and a resistor provided downstream of the first flow rate adjustment valve or the second flow rate adjustment valve and providing resistance to the flow of refrigerant, the five or more heat exchangers are three types of heat exchangers with different heat exchange capacities and are divided into a first group and a second group so that heat exchangers with the same heat exchange capacity are in the same group, and the first group is connected downstream of the first flow rate adjustment valve. the second group is connected downstream of the second flow control valve; a second branch section is provided between the first flow control valve and the first group, and the refrigerant flowing out from the first flow control valve is distributed in parallel to each of the plurality of heat exchangers belonging to the first group; a third branch section is provided between the second flow control valve and the second group, and the refrigerant flowing out from the second flow control valve is distributed in parallel to each of the plurality of heat exchangers belonging to the second group; at least one of the plurality of heat exchangers belonging to the first group and the plurality of heat exchangers belonging to the second group has the configuration (1); and the plurality of heat exchangers belonging to other than at least one of the first group and the second group have the configuration (1) or the configuration (2). (1) The refrigerant is divided into a first subgroup and a second subgroup, and the refrigerant is divided into two subgroups and flows through the first subgroup and the second subgroup, and a resistor is provided upstream of the subgroup with the smaller total refrigerant pressure loss between the first subgroup and the second subgroup. (2) The heat exchange capacities are set to be the same.

[0010] In an air conditioning apparatus according to the present disclosure, five or more heat exchangers are divided into first and second groups so that those with the same heat exchange capacity are in the same group, and flow rate distribution to each group is performed using a first flow control valve and a second flow control valve. Flow rate distribution to each heat exchanger downstream of the first flow control valve and the second flow control valve is performed using a two-branch pipe. This allows the air conditioning apparatus to achieve optimal refrigerant flow rate distribution at low cost while reducing the number of flow control valves.

[0011] 1 is a block diagram showing the configuration of an air conditioning apparatus according to embodiment 1. FIG. 2 is a schematic perspective view of a heat exchanger of the air conditioning apparatus according to embodiment 1. FIG. 3 is a schematic plan view of an outdoor unit showing an example of the arrangement of heat exchangers within the casing of the outdoor unit of the air conditioning apparatus according to embodiment 1. FIG. 4 is a block diagram showing the configuration of an air conditioning apparatus according to embodiment 2. FIG. 5 is a schematic plan view of an outdoor unit showing an example of the arrangement of heat exchangers within the casing of the outdoor unit of the air conditioning apparatus according to embodiment 2. FIG. 6 is a block diagram showing the configuration of an air conditioning apparatus according to embodiment 3. FIG. 7 is a schematic plan view of an outdoor unit showing an example of the arrangement of heat exchangers within the casing of the outdoor unit of the air conditioning apparatus according to embodiment 3.

[0012] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In each drawing, identical or corresponding parts are designated by the same reference numerals, and their description will be omitted or simplified as appropriate. Furthermore, the forms of components shown throughout the specification are merely examples and are not limited to these descriptions. Furthermore, to facilitate understanding, terms indicating directions or positions (e.g., "right," "left," "front," and "rear") will be used as appropriate. However, these notations are merely used for the convenience of explanation and do not limit the placement or orientation of devices or parts.

[0013] Embodiment 1. [Overall Configuration of Air Conditioning Apparatus 1] Figure 1 is a block diagram showing the configuration of an air conditioning apparatus 1 according to Embodiment 1. Figure 2 is a schematic perspective view of a heat exchanger 103 of the air conditioning apparatus 1 according to Embodiment 1. The air conditioning apparatus 1 includes an outdoor unit 100 and an indoor unit 200. The outdoor unit 100 includes a compressor 101, a four-way valve 102, multiple heat exchangers 103, a first flow control valve 104, a second flow control valve 105, an accumulator 106, and an outdoor blower 107 (see Figure 3 described below). The outdoor unit 100 also includes a first branch section 110, a second branch section 111, and a third branch section 112. The outdoor unit 100 also includes an on-off valve 120, a flow path switching valve 121, and a check valve 122. The indoor unit 200 includes a heat exchanger 201, a pressure reducing device 202, and an indoor blower (not shown).

[0014] The air conditioner 1 includes a compressor 101, a four-way valve 102, multiple heat exchangers 103, a pressure reducing device 202, a heat exchanger 201, and an accumulator 106, which are connected by refrigerant piping to form a refrigerant circuit 10 through which the refrigerant circulates. The air conditioner 1 performs heating operation and cooling operation by switching the four-way valve 102. Note that the air conditioner 1 is configured to be able to perform cooling operation or heating operation by switching the four-way valve 102, but it is sufficient if at least one of these operations is possible. The air conditioner 1 is configured to operate in such a way that at least the multiple heat exchangers 103 function as evaporators.

[0015] (Outdoor unit 100) The compressor 101 draws in a refrigerant and compresses it to a high-temperature, high-pressure state. The compressor 101 is a positive displacement compressor equipped with an inverter device (not shown) and capable of changing its operating frequency.

[0016] The four-way valve 102 switches the flow direction of the refrigerant in the refrigerant circuit 10 to switch between heating operation and cooling operation.

[0017] The air conditioning apparatus 1 includes five or more heat exchangers 103. Each of the heat exchangers 103 has the same configuration. As shown in FIG. 2 , the heat exchanger 103 includes a plurality of flat tubes 103a extending in the vertical direction, a plurality of corrugated fins 103b arranged between adjacent flat tubes 103a, and a pair of headers 103c arranged at both ends of the flat tubes 103a in the extension direction. Note that the heat exchanger 103 is not limited to the configuration shown in the figure. In the illustrated example, the heat exchanger 103 includes flat tubes 103a as heat transfer tubes, but the heat transfer tubes may be circular tubes. Furthermore, the heat exchanger 103 includes corrugated fins 103b as fins, but the fins may be plate fins. The heat exchangers 103 function as evaporators during heating operation and as condensers during cooling operation.

[0018] The header 103c is a cylindrical body with both ends closed, and a space is formed inside through which the refrigerant flows. In the illustrated example, the header 103c has a rectangular cross-sectional shape, but this is not limited to a rectangular shape and may be a circular or elliptical shape, or may be modified as appropriate. Furthermore, the structure of the header 103c may not be the above-mentioned cylindrical body with both ends closed, but may be, for example, a stack of plate-like bodies with slits formed therein. Furthermore, the pair of headers 103c may have different outer shapes or cross-sectional shapes.

[0019] One header 103c is provided with an inlet 103d1 through which the refrigerant flows in, and the other header 103c is provided with an outlet 103d2 through which the refrigerant flows out. The refrigerant that flows into one header 103c from the inlet 103d1 is distributed to each of the flat tubes 103a and flows from the lower end to the upper end of each flat tube 103a, then joins together in the other header 103c and flows out from the outlet 103d2.

[0020] 1 shows an example in which the number of heat exchangers 103 is five, the number of heat exchangers 103 may be five or more. In this specification, an example in which the number of heat exchangers 103 is five will be described. In the following description, the terms "upstream" and "downstream" refer to the flow of refrigerant when the heat exchanger 103 functions as an evaporator.

[0021] In the first embodiment, the air conditioning apparatus 1 has two types of heat exchangers 103 with different heat exchange capacities. The air conditioning apparatus 1 has a plurality of heat exchangers 103: heat exchanger A1, heat exchanger A2, heat exchanger B1, heat exchanger B2, and heat exchanger B3. Heat exchangers A1 and A2 have the same heat exchange capacity and refrigerant pressure loss. Heat exchangers B1, B2, and B3 have the same heat exchange capacity and refrigerant pressure loss. Hereinafter, heat exchanger A is a general term for heat exchanger A1 and heat exchanger A2. Furthermore, heat exchanger B is a general term for heat exchanger B1, heat exchanger B2, and heat exchanger B3.

[0022] Here, the heat exchange capacity is the amount of heat exchanged between the refrigerant and air when the volume of air passing through a unit area of ​​the heat exchanger is constant. The refrigerant pressure loss is the amount of pressure drop that occurs in the refrigerant from the inlet to the outlet of the heat exchanger 103. In this specification, the expression "same" does not necessarily mean "strictly the same," but also includes "substantially the same."

[0023] The heat exchange capacity of heat exchanger A is different from the heat exchange capacity of heat exchanger B. Assuming that the heat exchange capacity of heat exchanger A is Q1 and the heat exchange capacity of heat exchanger B is Q2, as an example, they have a relationship of Q1 > Q2. The refrigerant pressure loss is greater in a heat exchanger with a larger heat exchange capacity than in a heat exchanger with a smaller heat exchange capacity. Therefore, the refrigerant pressure loss of heat exchanger A is greater than the refrigerant pressure loss of heat exchanger B.

[0024] In this specification, the heat exchangers 103 have the same heat exchanger structure, but differ in heat exchange capacity due to the different external dimensions when viewed from the front. Therefore, "large size of the heat exchanger 103" is synonymous with "large heat exchange capacity." However, the heat exchangers 103 are not limited to having the same heat exchanger structure. For example, heat exchanger A and heat exchanger B may have different heat exchanger structures.

[0025] The first flow control valve 104 is configured, for example, as an electronic expansion valve, and adjusts the refrigerant flow rate by setting its opening degree, and functions as a pressure reducing valve or an expansion valve to reduce the pressure and expand the refrigerant. The first flow control valve 104 is provided on one pipe 10a of two pipes 10a and 10b branched at a first branch section 110 described below. The opening degree of the first flow control valve 104 is controlled by a control device (not shown).

[0026] The second flow control valve 105 is configured, for example, as an electronic expansion valve, and adjusts the refrigerant flow rate by setting its opening degree, and functions as a pressure reducing valve or an expansion valve to reduce the pressure and expand the refrigerant. The second flow control valve 105 is provided on the other pipe 10b of the two pipes 10a and 10b branched at a first branch section 110 described below. The opening degree of the second flow control valve 105 is controlled by a control device (not shown).

[0027] The accumulator 106 is provided on the suction side of the compressor 101, and is configured to separate the liquid refrigerant from the gas refrigerant, send the gas refrigerant to the compressor 101, and store the liquid refrigerant.

[0028] The outdoor blower 107 (see FIG. 3) is a fan that blows air, and is configured as a centrifugal fan, a multi-blade fan, or the like.

[0029] The first branch section 110 is composed of a first bifurcated pipe 110a, which is bifurcated into two on the downstream side, one of which is connected to the pipe 10a and the other of which is connected to the pipe 10b.

[0030] The second branch section 111 is composed of one or more second bifurcated pipes 111a. In the illustrated example, the second branch section 111 is composed of one second bifurcated pipe 111a. Whether the second branch section 111 is composed of one bifurcated pipe or multiple bifurcated pipes depends on the number of heat exchangers 103 connected downstream of the second branch section 111. The number of second bifurcated pipes 111a is the number of heat exchangers 103 connected downstream of the second branch section 111 minus one. In the illustrated example, because there are two heat exchangers 103 connected downstream of the second branch section 111, the number of second bifurcated pipes 111a is one.

[0031] The third branch section 112 is composed of one or more third bifurcated pipes. In the illustrated example, the third branch section 112 is composed of two third bifurcated pipes 112a and 112b. Whether the third branch section 112 is composed of one bifurcated pipe or multiple bifurcated pipes depends on the number of heat exchangers 103 connected downstream of the third branch section 112. The number of bifurcated pipes is the number of heat exchangers 103 provided downstream of the third branch section 112 minus one. In the illustrated example, because there are three heat exchangers 103 connected downstream of the third branch section 112, the number of bifurcated pipes is two, and the third branch section 112 is composed of two third bifurcated pipes, 112a and 112b.

[0032] The on-off valve 120, the flow path switching valve 121, and the check valve 122 are not relevant to the gist of the present disclosure, and therefore their description will be omitted.

[0033] (Indoor unit 200) The heat exchanger 201 is configured, for example, as a fin-and-tube heat exchanger having heat transfer tubes and fins. The heat transfer tubes are configured as flattened or circular tubes with a cross-sectional shape that is flattened in one direction, such as an oval shape. The fins are, for example, corrugated fins or plate fins. The heat exchanger 201 functions as a condenser during heating operation and as an evaporator during cooling operation.

[0034] The pressure reducing device 202 is configured by, for example, an electronic expansion valve, and adjusts the refrigerant flow rate by setting the opening degree, and functions as a pressure reducing valve or an expansion valve to reduce the pressure of the refrigerant and expand it.

[0035] (Arrangement of heat exchanger 103) Fig. 3 is a schematic plan view of the outdoor unit 100 showing an example of the arrangement of the heat exchanger 103 within the housing 100a of the outdoor unit 100 of the air conditioning apparatus 1 according to Embodiment 1. In Fig. 3, devices other than the heat exchanger 103 and the outdoor blower 107 are omitted from the illustration. The housing 100a is formed in a rectangular parallelepiped shape and has a front wall 100a1, a rear wall 100a2, a left wall 100a3, a right wall 100a4, a bottom wall (not shown), and a top wall (not shown). When the outdoor blower 107 is operating, air flows from the rear to the front within the housing 100a.

[0036] The air conditioning device 1 has a configuration in which heat exchangers 103 of the same size are arranged in regions within the housing 100a where the airflow volume is the same. Airflow distribution occurs within the housing 100a, but the region within the housing 100a along the rear wall 100a2 has the same airflow distribution in the left-right direction. Furthermore, within the housing 100a, the regions within the housing 100a along the left wall 100a3, right wall 100a4, and front wall 100a1 each have the same airflow distribution.

[0037] 3, the air conditioning device 1 has a configuration in which heat exchangers A1 and A2 are arranged side by side in the left-right direction along the rear wall 100a2, and this arrangement ensures that the airflow volumes passing through the heat exchangers A1 and A2 are equal. The air conditioning device 1 also has a configuration in which heat exchangers B1, B2, and B3 are arranged, in that order, along the left wall 100a3, right wall 100a4, and front wall 100a1 within the housing 100a. This arrangement ensures that the airflow volumes passing through the heat exchangers B1, B2, and B3 are equal.

[0038] [Refrigerant Distribution Structure] The air conditioning apparatus 1 has the following distribution structure to achieve optimal refrigerant flow distribution among the five heat exchangers 103. As shown in FIG. 1 , the five heat exchangers 103 are divided into a first group G1 and a second group G2. In the first embodiment, the five heat exchangers 103 are grouped into the first group G1 and the second group G2 so that heat exchangers with the same heat exchange capacity are in the same group. Therefore, of the five heat exchangers 103, heat exchangers A1 and A2 with a heat exchange capacity Q1 are classified into the first group G1, and heat exchangers B1, B2, and B3 with a heat exchange capacity Q2 are classified into the second group G2.

[0039] Here, optimal refrigerant distribution means distributing the refrigerant according to the heat exchange capacity of the heat exchangers 103. More specifically, optimal refrigerant distribution means first distributing a relatively large amount of refrigerant to a group with a large heat exchange capacity, and a relatively small amount of refrigerant to a group with a small heat exchange capacity. Optimal refrigerant distribution also means distributing the refrigerant distributed to each group to each of the multiple heat exchangers 103 belonging to that group according to the heat exchange capacity of the heat exchanger 103. The air conditioning apparatus 1 achieves this optimal refrigerant distribution using a minimum number of flow control valves and two-branch pipes.

[0040] For example, when the ratio of the total heat exchange capacity of the first group G1 to the total heat exchange capacity of the second group G2 is, for example, 3:4, the refrigerant is first distributed between the first group G1 and the second group G2 at a flow rate of 3:4. The air conditioning device 1 distributes the refrigerant between the first group G1 and the second group G2 by adjusting the opening degrees of the first flow control valve 104 and the second flow control valve 105.

[0041] The air conditioning apparatus 1 then distributes the refrigerant to each of the multiple heat exchangers 103 that belong to the same group using a two-branch pipe. Here, the multiple heat exchangers 103 are grouped according to their heat exchange capacities, and the heat exchangers 103 that belong to the same group have the same heat exchange capacity. Therefore, after the air conditioning apparatus 1 distributes the refrigerant to each group using a flow control valve according to the group's total heat exchange capacity, there is no need to adjust the flow rate using a flow control valve, and the air conditioning apparatus 1 can optimally distribute the refrigerant to the heat exchangers 103 using a two-branch pipe. In other words, the air conditioning apparatus 1 can optimally distribute the refrigerant to the multiple heat exchangers 103 using a minimum of two flow control valves and a number of two-branch pipes that is fewer than the number of heat exchangers 103.

[0042] A specific refrigerant distribution structure will be described below using an example in which the heat exchanger 103 shown in FIG. 1 has five units.

[0043] The air conditioning device 1 has a first branch section 110 at the most upstream of the refrigerant distribution structure, and a first flow control valve 104 is provided on one of two pipes 10a and 10b branched at the first branch section 110, namely pipe 10a, and a second flow control valve 105 is provided on pipe 10b. In the air conditioning device 1, a first group G1 is connected downstream of the first flow control valve 104, and a second group G2 is connected downstream of the second flow control valve 105.

[0044] The air conditioning apparatus 1 has a second branch section 111 between the first flow control valve 104 and the first group G1. Because there are two heat exchangers 103 belonging to the first group G1, the second branch section 111 is composed of one second two-branch pipe 111a, and the second two-branch pipe 111a branches into two, one of which is connected to the pipe 11a and the other of which is connected to the pipe 11b.

[0045] With this configuration, the air conditioning apparatus 1 branches the refrigerant flowing out of the first flow control valve 104 into two at the second bifurcated pipe 111a, and distributes one to the heat exchanger A1 via the pipe 11a and the other to the heat exchanger A2 via the pipe 11b. In other words, the air conditioning apparatus 1 distributes the refrigerant flowing out of the first flow control valve 104 in parallel to the heat exchangers A1 and A2. Here, because the heat exchangers A1 and A2 are heat exchangers 103 with the same heat exchange capacity and also have the same airflow rate, flow rate adjustment by a flow control valve is not necessary, and optimal flow rate distribution can be performed using the second bifurcated pipe 111a.

[0046] The air conditioning apparatus 1 is provided with a third branch section 112 between the second flow control valve 105 and the second group G2. Because there are three heat exchangers 103 belonging to the second group G2, the third branch section 112 is composed of two third bifurcated pipes 112a and 112b. The third bifurcated pipe 112a is connected upstream of the third bifurcated pipe 112b, and the third bifurcated pipe 112b is connected downstream of the third bifurcated pipe 112a. The air conditioning apparatus 1 first branches the refrigerant flowing out of the second flow control valve 105 into two at the third bifurcated pipe 112a, and one of the refrigerant branches further into two at the third bifurcated pipe 112b, for a total of three branches.

[0047] Specifically, the air conditioning device 1 has a configuration in which a third bifurcated pipe 112a branches into two at the third branch section 112, one of which is connected to the pipe 12a and the other to the pipe 12b, and the third bifurcated pipe 112b is connected to the pipe 12a and further branches into two. As a result, a total of three branched flow paths are formed at the third branch section 112 in the air conditioning device 1, and heat exchangers B1, B2, and B3 are connected to the three branched flow paths.

[0048] With this configuration, the air conditioning device 1 distributes the refrigerant flowing out from the second flow control valve 105 in parallel to each of the heat exchangers B1, B2, and B3. Here, because the heat exchangers B1, B2, and B3 are heat exchangers 103 with the same heat exchange capacity and also have the same airflow rate, flow rate adjustment by a flow control valve is not necessary, and flow rate distribution can be performed using the third two-branch pipes 112a and 112b.

[0049] In the above example, the number of heat exchangers 103 is five, two are classified into the first group G1, and three are classified into the second group G2. However, this classification is not limited to this. The number of heat exchangers 103 may be five, three are classified into the first group G1, and two are classified into the second group G2. Furthermore, the number of heat exchangers 103 is not limited to five as described above, but may be any number equal to or greater than five. Therefore, for example, the number of heat exchangers 103 may be six, three are classified into the first group G1 and three are classified into the second group G2, or two are classified into the first group G1 and four are classified into the second group G2. When the number of heat exchangers 103 is six, the air conditioning apparatus 1 distributes the refrigerant to each heat exchanger 103 using two flow control valves and four two-branch pipes.

[0050] [Operation of Air Conditioning Apparatus 1] The air conditioning apparatus 1 configured as described above is capable of heating or cooling operation by switching the four-way valve 102. When the four-way valve 102 is switched to the solid line side in Fig. 1, the heat exchanger 201 functions as a condenser, the heat exchanger 103 functions as an evaporator, and heating operation is performed. When the four-way valve 102 is switched to the dotted line side in Fig. 1, the heat exchanger 201 functions as an evaporator, the heat exchanger 103 functions as a condenser, and cooling operation is performed.

[0051] (Refrigeration Cycle Operation During Heating) During heating operation, the four-way valve 102 is switched to the state indicated by the solid line in FIG. 1 . The refrigerant compressed by the compressor 101 becomes a high-temperature, high-pressure gas refrigerant and flows through the four-way valve 102 into the heat exchanger 201. The refrigerant that flows into the heat exchanger 201 exchanges heat with the indoor air, condenses, and liquefies. The indoor air is heated by the refrigerant, and the heated indoor air is supplied to the indoor space to heat the room. The liquefied refrigerant is decompressed by the pressure reducing device 202 to a gas-liquid two-phase state. The refrigerant is then branched into the first branch section 110, the second branch section 111, and the third branch section 112 and flows into each of the heat exchangers 103. The refrigerants that flow into the heat exchangers 103 exchange heat with the outdoor air, evaporating and becoming gasified. The gasified refrigerants are then combined, pass through the four-way valve 102 and the accumulator 106, and return to the compressor 101.

[0052] Here, because the air conditioning apparatus 1 has the above-described refrigerant distribution structure, optimal refrigerant flow distribution is performed in each heat exchanger 103. This allows the air conditioning apparatus 1 to improve heat exchange efficiency compared to a configuration that does not have the above-described refrigerant distribution structure.

[0053] (Refrigeration cycle operation during cooling) In cooling operation, the four-way valve 102 is switched to the state shown by the dotted line in Fig. 1. The refrigerant compressed by the compressor 101 becomes a high-temperature, high-pressure gas refrigerant and passes through the four-way valve 102. The gas refrigerant that has passed through the four-way valve 102 is distributed to and passes through heat exchangers B1, B2, and B3, then joins together and passes through the on-off valve 120, and is distributed to and passes through heat exchangers A1 and A2. The refrigerant that has passed through heat exchangers B and A passes through the first flow control valve 104, and is then decompressed by the pressure reducing device 202.

[0054] The decompressed refrigerant flows into the heat exchanger 201. The refrigerant that flows into the heat exchanger 201 exchanges heat with the indoor air and is gasified by dissipating heat. At this time, the indoor air is cooled by the refrigerant, and the cooled indoor air is supplied to the indoor space to cool the room. The gasified refrigerant passes through the four-way valve 102 and the accumulator 106 and returns to the compressor 101.

[0055] [Effects of the Air Conditioning Apparatus 1] The air conditioning apparatus 1 includes a refrigerant circuit 10 having five or more heat exchangers 103 and through which a refrigerant circulates. The refrigerant circuit 10 includes a first branch section 110, a first flow control valve 104, a second flow control valve 105, a second branch section 111, and a third branch section 112. The first branch section 110 is composed of a single two-branch pipe 110a. The first flow control valve 104 is provided on one pipe 10a of two pipes 10a and 10b branched at the first branch section 110. The second flow control valve 105 is provided on the other pipe 10b of two pipes 10a and 10b branched at the first branch section 110. The second branch section 111 is composed of a single second two-branch pipe 111a. The third branch section 112 is composed of two third bifurcated pipes 112a and 112b. The five or more heat exchangers 103 are divided into a first group G1 and a second group G2 so that heat exchangers with the same heat exchange capacity are grouped together. The first group G1 is connected downstream of the first flow control valve 104, and the second group G2 is connected downstream of the second flow control valve 105. A second branch section 111 is provided between the first flow control valve 104 and the first group G1, so that the refrigerant flowing out of the first flow control valve 104 is distributed in parallel to each of the heat exchangers 103 belonging to the first group G1. A third branch section 112 is provided between the second flow control valve 105 and the second group G2, so that the refrigerant flowing out of the second flow control valve 105 is distributed in parallel to each of the heat exchangers 103 belonging to the second group G2.

[0056] With the above configuration, the air conditioning device 1 can achieve optimal flow distribution of the refrigerant at low cost by using two branch pipes while reducing the number of flow control valves to two compared to a configuration having the same number of flow control valves as the number of heat exchangers.

[0057] Second Embodiment The following description will focus on the configuration of a second embodiment that differs from that of the first embodiment, and the configuration not described in the second embodiment is the same as that of the first embodiment.

[0058] Fig. 4 is a block diagram showing the configuration of the air conditioning apparatus 1 according to embodiment 2. Fig. 5 is a schematic plan view of the outdoor unit 100 showing an example of the arrangement of the heat exchanger 103 within the housing 100a of the outdoor unit 100 of the air conditioning apparatus 1 according to embodiment 2.

[0059] The air conditioning apparatus 1 of the first embodiment has an effective structure in that the heat exchange capacity of the heat exchangers B1 and B2 is the same, and therefore the refrigerant can be distributed to them by the third two-branch pipe 112b rather than by a flow control valve. However, when the heat exchanger B3 is also considered, since the heat exchange capacities of the heat exchangers B1, B2, and B3 are the same, it is desirable that the refrigerant be distributed in a 1:1:1 ratio.

[0060] However, in the air conditioning apparatus 1 of embodiment 1, if the refrigerant were distributed equally between the third bifurcated pipe 112a and the third bifurcated pipe 112b, the refrigerant would be distributed to the heat exchangers B1, B2, and B3 at a distribution ratio of 1:1:2. Furthermore, because the refrigerant distribution is also affected by the refrigerant pressure loss of the heat exchanger 103, the air conditioning apparatus 1 is required to distribute the refrigerant while taking into account the refrigerant pressure loss of the heat exchanger 103. Embodiment 2 is an embodiment that aims to improve on the above points. For simplicity of explanation, it is assumed below that heat exchangers 103 with the same heat exchange capacity also have the same refrigerant pressure loss.

[0061] The air conditioning apparatus 1 of embodiment 2 has three types of heat exchangers 103 with different heat exchange capacities. The air conditioning apparatus 1 has heat exchanger A1, heat exchanger A2, heat exchanger B1, heat exchanger B2, and heat exchanger C1 as the multiple heat exchangers 103. The heat exchange capacities Q1 of heat exchangers A1 and A2, Q2 of heat exchangers B1 and B2, and Q3 of heat exchanger C1 are all different, and in the illustrated example, Q3 > Q1 > Q2.

[0062] The air conditioning apparatus 1 of the second embodiment has a configuration in which heat exchanger C1, which has a heat exchange capacity and refrigerant pressure loss that match the refrigerant distribution ratio, is selected as heat exchanger B3 from among heat exchangers B1, B2, and B3 of the first embodiment. Heat exchanger C1 has the combined heat exchange capacity of heat exchangers B1 and B2 and the combined refrigerant pressure loss of heat exchangers B1 and B2. The other configurations of the air conditioning apparatus 1 of the second embodiment are the same as those of the first embodiment.

[0063] With the above configuration, the air conditioning device 1 of embodiment 2 has a ratio of the heat exchange capacity between heat exchanger B1, heat exchanger B2, and heat exchanger C1 and a ratio of the refrigerant pressure loss of 1:1:2, which can be adjusted to match the refrigerant distribution ratio, allowing for more optimal refrigerant distribution.

[0064] [Refrigerant distribution structure] The air conditioning apparatus 1 of embodiment 2 has the following distribution structure to achieve optimal refrigerant flow distribution to each of the five heat exchangers 103. The following describes the air conditioning apparatus 1 of embodiment 2, focusing on the differences from the refrigerant distribution structure of embodiment 1.

[0065] As in the first embodiment, the air conditioning apparatus 1 of the second embodiment is divided into a first group G1 and a second group G2 such that refrigerants with the same heat exchange capacity are grouped together. The first subgroup SG1 and the second subgroup SG2 are configured so that the refrigerant branched into two by the third two-way branch valve 112a flows through the first subgroup SG1 and the second subgroup SG2. In the second embodiment, there are three types of heat exchange capacities, so one type of heat exchanger 103 is classified into the first group G1, and the other two types of heat exchangers 103 are classified into the second group G2. Specifically, heat exchangers A1 and A2 with a heat exchange capacity Q1 are classified into the first group G1, and heat exchangers B1 and B2 with a heat exchange capacity Q2 and heat exchanger C1 with a heat exchange capacity Q3 are classified into the second group G2.

[0066] In the air conditioning apparatus 1 of the second embodiment, the heat exchangers B1, B2, and C1 belonging to the second group G2 are divided into a first subgroup SG1 and a second subgroup SG2 based on their refrigerant pressure losses. The heat exchangers B1, B2, and C1 belonging to the second group G2 are divided into subgroups so that the total refrigerant pressure loss of the first subgroup SG1 is the same as the total refrigerant pressure loss of the second subgroup SG2. In other words, the total refrigerant pressure loss of the first subgroup SG1 is set to be the same as the total refrigerant pressure loss of the second subgroup SG2.

[0067] In the example of Figure 4, heat exchangers B1 and B2 are classified into a first subgroup SG1, and heat exchanger C1 is classified into a second subgroup SG2. The total refrigerant pressure loss of the first subgroup SG1 is the sum of the refrigerant pressure loss of heat exchanger B1 and the refrigerant pressure loss of heat exchanger B2. In this example, the only heat exchanger 103 belonging to the second subgroup SG2 is heat exchanger C1, so the total refrigerant pressure loss of the second subgroup SG2 is the refrigerant pressure loss of heat exchanger C1. When the refrigerant pressure loss of heat exchangers B1 and B2 is ΔP1 and the refrigerant pressure loss of heat exchanger C1 is ΔP2, ΔP2 = 2 × ΔP1.

[0068] [Effects of Air Conditioning Apparatus 1] With the above configuration, the air conditioning apparatus 1 can achieve the same effects as in embodiment 1, and because the total refrigerant pressure loss of the first subgroup SG1 and the total refrigerant pressure loss of the second subgroup SG2 are set to be the same, the air conditioning apparatus 1 can achieve the following effects: The air conditioning apparatus 1 distributes the refrigerant equally in the third two-branch pipe 112a into two parts at a flow rate, and passes each part through the first subgroup SG1 and the second subgroup SG2, which have the same refrigerant pressure loss, thereby achieving more optimal flow rate distribution than in embodiment 1.

[0069] Although the configuration has been described here in which the heat exchangers 103 belonging to the second group G2 are divided into subgroups according to refrigerant pressure loss and the refrigerant pressure loss is the same among the subgroups, the configuration is not limited to this. In the air conditioning device 1, the first group G1 may have this configuration, or both the first group G1 and the second group G2 may have the above configuration.

[0070] In short, in the air conditioning apparatus 1, the multiple heat exchangers 103 belonging to at least one of the first group G1 and the second group G2 have the following configuration (1): (1) They are divided into a first subgroup SG1 and a second subgroup SG2, and the refrigerant branched into two is distributed and flows through the first subgroup SG1 and the second subgroup SG2. The total refrigerant pressure loss of the first subgroup SG1 and the total refrigerant pressure loss of the second subgroup SG2 are set to be the same.

[0071] In the air conditioning device 1, the heat exchangers 103 belonging to at least one other than the first group G1 and the second group G2 have the configuration (1) above or the configuration (2) below: (2) The heat exchange capacities are set to be the same.

[0072] Third Embodiment The following description will focus on the configuration of a third embodiment that differs from the second embodiment, and the configuration not described in the third embodiment is the same as that in the second embodiment.

[0073] Fig. 6 is a block diagram showing the configuration of the air conditioning apparatus 1 according to embodiment 3. Fig. 7 is a schematic plan view of the outdoor unit 100 showing an example of the arrangement of the heat exchanger 103 within the housing 100a of the outdoor unit 100 of the air conditioning apparatus 1 according to embodiment 3.

[0074] The air conditioning apparatus 1 of the second embodiment described above sets the total refrigerant pressure loss of the first subgroup SG1 and the total refrigerant pressure loss of the second subgroup SG2 to be the same, thereby making the refrigerant pressure loss of the two branch flow paths downstream of the third bifurcated pipe 112a the same.The air conditioning apparatus 1 of the third embodiment uses the resistor 130 to make the refrigerant pressure loss of the two branch flow paths downstream of the third bifurcated pipe 112a the same.

[0075] The air conditioning apparatus 1 of embodiment 3 has three types of heat exchangers 103 with different heat exchange capacities, similar to embodiment 2. The air conditioning apparatus 1 has heat exchanger A1, heat exchanger A2, heat exchanger B1, heat exchanger B2, and heat exchanger C2 as the multiple heat exchangers 103. The heat exchange capacities Q1 of heat exchangers A1 and A2, Q2 of heat exchangers B1 and B2, and Q4 of heat exchanger C2 are all different from one another, and in the illustrated example, Q1 > Q2 > Q4.

[0076] The air conditioning apparatus 1 of embodiment 3 differs from the air conditioning apparatus 1 of embodiment 2 in that the heat exchange capacity and refrigerant pressure loss of heat exchanger C2 are smaller than the heat exchange capacity and refrigerant pressure loss of heat exchanger C1, and in that heat exchanger C2 is provided with resistor 130. In the air conditioning apparatus 1 of embodiment 3, heat exchanger C2 belonging to second subgroup SG2 has a smaller refrigerant pressure loss than heat exchanger C1 of embodiment 2, and therefore the total refrigerant pressure loss of second subgroup SG2 is smaller than the total refrigerant pressure loss of first subgroup SG1.

[0077] Resistor 130 acts as a resistance to the refrigerant flow and adjusts the difference between the total refrigerant pressure loss of first subgroup SG1 and the total refrigerant pressure loss of second subgroup SG2. Resistor 130 has a refrigerant pressure loss equivalent to the difference between the total refrigerant pressure loss of heat exchangers B1 and B2 and the refrigerant pressure loss of heat exchanger C2. When the refrigerant pressure loss of each of heat exchangers B1 and B2 is ΔP1 and the refrigerant pressure loss of heat exchanger C2 is ΔP3, ΔP3 < 2 × ΔP1, and the refrigerant pressure loss ΔP4 of resistor 130 is ΔP4 = 2 × ΔP1 - ΔP3. As a result, the air conditioning device 1 has the same refrigerant pressure loss in the two branch flow paths downstream of the third bifurcated pipe 112a.

[0078] The resistor 130 is, for example, a thin tube in the pipe 12b having a diameter smaller than that of the pipe 12b, or a capillary tube. The resistor 130 may also be a valve provided in the pipe.

[0079] [Refrigerant distribution structure] As described above, the air conditioning apparatus 1 of embodiment 3 differs from the air conditioning apparatus 1 of embodiment 2 in that it is provided with a resistor 130, but the rest of the refrigerant distribution structure is the same as that of embodiment 2. The air conditioning apparatus 1 of embodiment 3 is provided with the resistor 130 upstream of the second subgroup SG2, which is the subgroup with the smaller refrigerant pressure loss, specifically in the pipe 12b.

[0080] The second group G2 is divided into a first subgroup SG1 and a second subgroup SG2, and the refrigerant branched into two is distributed between the first subgroup SG1 and the second subgroup SG2. The total refrigerant pressure loss of the first subgroup SG1 and the total refrigerant pressure loss of the second subgroup SG2 are different from each other, and a resistor 130 is provided upstream of the subgroup with the smaller total refrigerant pressure loss to adjust the difference in the total refrigerant pressure loss.

[0081] [Effects of Air Conditioning Apparatus 1] With the above configuration, the air conditioning apparatus 1 can achieve the same effects as in embodiment 2. Specifically, by including resistor 130, air conditioning apparatus 1 equalizes the refrigerant pressure loss in the two branch flow paths downstream of third bifurcated pipe 112a. As a result, the air conditioning apparatus 1 can divide the refrigerant, which has been equally divided into two flow paths in third bifurcated pipe 112a, and pass each of the refrigerant through two branch flow paths with the same refrigerant pressure loss, thereby achieving more optimal refrigerant flow distribution than in embodiment 1, as in embodiment 2.

[0082] Although the configuration in which the resistor 130 is provided in the second subgroup SG2 of the second group G2 has been described here, the resistor 130 may be provided in the first subgroup SG1. Furthermore, the resistor 130 may be provided in the first group G1 when the number of heat exchangers 103 belonging to the first group G1 is three or more.

[0083] In short, in the air conditioning apparatus 1, the multiple heat exchangers 103 belonging to at least one of the first group G1 and the second group G2 have the following configuration (1): (1) The heat exchangers 103 are divided into a first subgroup SG1 and a second subgroup SG2, and the refrigerant branched into two is distributed and flows through the first subgroup SG1 and the second subgroup SG2. A resistor 130 that adjusts the difference in total refrigerant pressure loss is provided upstream of the subgroup with the smaller total refrigerant pressure loss, either the first subgroup SG1 or the second subgroup SG2.

[0084] In the air conditioning device 1, the heat exchangers 103 belonging to at least one other than the first group G1 and the second group G2 have the configuration (1) above or the configuration (2) below: (2) The heat exchange capacities are set to be the same.

[0085] 1 Air conditioning apparatus, 10 Refrigerant circuit, 10a Pipe, 10b Pipe, 11a Pipe, 11b Pipe, 12a Pipe, 12b Pipe, 100 Outdoor unit, 100a Housing, 100a1 Front wall, 100a2 Rear wall, 100a3 Left wall, 100a4 Right wall, 101 Compressor, 102 Four-way valve, 103 Heat exchanger, 103a Flat tube, 103b Corrugated fin, 103c Header, 103d1 Inlet, 103d2 Outlet, 104 First flow control valve, 105 Second flow control valve, 106 Accumulator, 107 Outdoor blower, 110 First branch, 110a First bifurcated pipe, 111 Second branch, 111a Second bifurcated pipe, 112 Third branch section, 112a third two-way branch valve, 112b third two-way branch valve, 120 on-off valve, 121 flow path switching valve, 122 check valve, 130 resistor, 200 indoor unit, 201 heat exchanger, 202 pressure reducing device, A heat exchanger, A1 heat exchanger, A2 heat exchanger, B heat exchanger, B1 heat exchanger, B2 heat exchanger, B3 heat exchanger, C1 heat exchanger, C2 heat exchanger, G1 first group, G2 second group, Q1 heat exchange capacity, Q2 heat exchange capacity, Q3 heat exchange capacity, Q4 heat exchange capacity, SG1 first subgroup, SG2 second subgroup.

Claims

1. a refrigerant circuit having five or more heat exchangers and through which a refrigerant circulates; The refrigerant circuit includes: a first branch portion configured with a first two-branch pipe; a first flow rate adjustment valve provided in one of the two pipes branched at the first branch portion and a second flow rate adjustment valve provided in the other of the two pipes; a second branch portion composed of one or more second two-branch pipes; a third branch portion composed of one or more third two-branch pipes, the five or more heat exchangers are divided into a first group and a second group such that heat exchangers having the same heat exchange capacity are in the same group; the first group is connected downstream of the first flow rate adjustment valve, and the second group is connected downstream of the second flow rate adjustment valve; the second branch portion is provided between the first flow rate adjustment valve and the first group, and the refrigerant flowing out from the first flow rate adjustment valve is distributed in parallel to each of the plurality of heat exchangers belonging to the first group, The air conditioning apparatus is configured such that the third branch portion is provided between the second flow control valve and the second group, and the refrigerant flowing out from the second flow control valve is distributed in parallel to each of the multiple heat exchangers belonging to the second group.

2. a refrigerant circuit having five or more heat exchangers and through which a refrigerant circulates; The refrigerant circuit includes: a first branch portion configured with a first two-branch pipe; a first flow rate adjustment valve provided in one of the two pipes branched at the first branch portion and a second flow rate adjustment valve provided in the other of the two pipes; a second branch portion composed of one or more second two-branch pipes; a third branch portion composed of one or more third two-branch pipes, the five or more heat exchangers are three types of heat exchangers with different heat exchange capacities, and are divided into a first group and a second group such that heat exchangers with the same heat exchange capacity are in the same group, the first group is connected downstream of the first flow rate adjustment valve, and the second group is connected downstream of the second flow rate adjustment valve, the second branch portion is provided between the first flow rate adjustment valve and the first group, and the refrigerant flowing out from the first flow rate adjustment valve is distributed in parallel to each of the plurality of heat exchangers belonging to the first group, the third branch portion is provided between the second flow rate adjustment valve and the second group, and the refrigerant flowing out from the second flow rate adjustment valve is distributed in parallel to each of the plurality of heat exchangers belonging to the second group, The plurality of heat exchangers belonging to at least one of the first group and the second group have a configuration of (1), An air conditioning apparatus, wherein the plurality of heat exchangers belonging to a group other than at least one of the first group and the second group have the configuration of (1) or (2). (1) The refrigerant is divided into a first subgroup and a second subgroup, and the refrigerant branched into two is distributed and flows through the first subgroup and the second subgroup, and the total refrigerant pressure loss of the first subgroup and the total refrigerant pressure loss of the second subgroup are set to be the same. (2) The heat exchange capacities are set to be the same.

3. a refrigerant circuit having five or more heat exchangers and through which a refrigerant circulates; The refrigerant circuit includes: a first branch portion configured with a first two-branch pipe; a first flow rate adjustment valve provided in one of the two pipes branched at the first branch portion and a second flow rate adjustment valve provided in the other of the two pipes; a second branch portion composed of one or more second two-branch pipes; a third branch portion composed of one or more third bifurcated pipes; a resistor provided downstream of the first flow rate adjustment valve or the second flow rate adjustment valve and providing resistance to the flow of the refrigerant, the five or more heat exchangers are three types of heat exchangers with different heat exchange capacities, and are divided into a first group and a second group such that heat exchangers with the same heat exchange capacity are in the same group, the first group is connected downstream of the first flow rate adjustment valve, and the second group is connected downstream of the second flow rate adjustment valve, the second branch portion is provided between the first flow rate adjustment valve and the first group, and the refrigerant flowing out from the first flow rate adjustment valve is distributed in parallel to each of the plurality of heat exchangers belonging to the first group, the third branch portion is provided between the second flow rate adjustment valve and the second group, and the refrigerant flowing out from the second flow rate adjustment valve is distributed in parallel to each of the plurality of heat exchangers belonging to the second group, At least one of the plurality of heat exchangers belonging to the first group and the plurality of heat exchangers belonging to the second group has the configuration of (1), An air conditioning apparatus, wherein the plurality of heat exchangers belonging to a group other than at least one of the first group and the second group have the configuration of (1) or (2). (1) The refrigerant is divided into a first subgroup and a second subgroup, and the refrigerant is divided into two branches and flows through the first subgroup and the second subgroup. The resistor is provided upstream of the subgroup with the smaller total refrigerant pressure loss between the first subgroup and the second subgroup. (2) The heat exchange capacities are set to be the same.

4. 4. The air conditioner according to claim 3, wherein the resistor has a refrigerant pressure loss corresponding to the difference in the total refrigerant pressure loss.

5. One of the three types of heat exchangers belongs to the first group, and the remaining two types of heat exchangers belong to the second group; An air conditioning apparatus according to any one of claims 2 to 4, wherein one of the remaining two types of heat exchangers belongs to the first subgroup, and the other type of heat exchanger belongs to the second subgroup.

6. a housing having the five or more heat exchangers disposed therein; An air conditioning apparatus as described in any one of claims 1 to 4, wherein the five or more heat exchangers are arranged inside the housing so that the air flow rate is equal between the heat exchangers belonging to the first group, and the air flow rate is equal between the heat exchangers belonging to the second group.

7. The housing is rectangular parallelepiped and has a front wall, a rear wall, a left wall, and a right wall, the plurality of heat exchangers belonging to the first group are arranged along the rear wall; The air conditioner according to claim 6, wherein the plurality of heat exchangers belonging to the second group are arranged along the left wall, the right wall, and the front wall.

8. the five or more heat exchangers is five heat exchangers; The plurality of heat exchangers belonging to the first group are two, the number of the heat exchangers belonging to the second group is three, the second branch portion is composed of one of the second two-branch pipes, The air conditioning apparatus according to any one of claims 1 to 4, wherein the third branch portion is made up of two of the third bifurcated pipes.

9. the refrigerant circuit includes a compressor, a condenser, a pressure reducing device, and an evaporator; The air conditioner according to any one of claims 1 to 4, wherein the evaporator is composed of five or more heat exchangers.

10. Each of the five or more heat exchangers A plurality of flat tubes; The air conditioning apparatus according to any one of claims 1 to 4, further comprising: a plurality of corrugated fins arranged between adjacent flat tubes in the plurality of flat tubes.