Air conditioning unit and refrigeration cycle device

Abstract

This air conditioning unit comprises: a housing in which an inlet and an outlet are provided; a first heat exchanger and a second heat exchanger which are disposed side by side along an inner surface of the housing, and which are each opposite from the inlet; and a first blower and a second blower which are disposed side by side inside the housing, the first blower being opposite from the first heat exchanger, the second blower being opposite from the second heat exchanger. The first blower has a centrifugal first fan and a first casing inside which the first fan is accommodated, which forms an airflow path for the first fan, and in which an intake surface that has an intake opening formed therein is disposed along the first heat exchanger. The second blower has a centrifugal second fan and a second casing inside which the second fan is accommodated, which forms an airflow path for the second fan, and in which an intake surface that has an intake opening formed therein is disposed along the second heat exchanger.

Description

Air conditioning units and refrigeration cycle devices

[0001] The present disclosure relates to an air conditioning unit and a refrigeration cycle device equipped with multiple fans.

[0002] Some air conditioning units (e.g., outdoor units of air conditioners) include a box-shaped housing (hereinafter also referred to as a main casing) including a rear panel with an air intake and a front panel with two air outlets, a first fan and a second fan arranged side by side within the housing along the front panel so as to face the two air outlets, and a first heat exchanger unit facing the first fan and a second heat exchanger unit facing the second fan, also arranged side by side within the housing along the rear panel with the air intake (see, for example, Patent Document 1). In Patent Document 1, the main casing of the outdoor unit further includes a front partition plate with two bell mouths, which is adjacent to the rear side of the front panel. In the outdoor unit of Patent Document 1, the first and second heat exchanger units constituting the outdoor heat exchanger are arranged one above the other. The bottom plate of the drain pan, which is provided below the upper first heat exchanger section, extends horizontally forward, passing between the first and second fans and up to the front partition plate. In this way, the extension of the bottom plate of the drain pan (hereinafter also referred to as the plate-shaped component) is positioned between the two fans, particularly between the two bell mouths, thereby dividing the air passage within the main casing into an air passage for the first fan and an air passage for the second fan.

[0003] In Patent Document 1, the air conditioner includes a refrigerant circuit that can alternately perform defrosting operations on the first and second heat exchangers without reversing the refrigeration cycle during heating operation. During this heating / defrosting operation, the fan facing the heat exchanger being defrosted is stopped. In Patent Document 1, a plate-shaped component extending from rear to front and located between two bellmouths separates the air passages of the two fans, preventing the fan facing the heat exchanger in heating operation from drawing in air passing through the heat exchanger being defrosted. In other words, in the air conditioning unit of Patent Document 1, the fan only has a bellmouth with a depth approximately equal to the fan's width in the front-to-rear direction. Without the plate-shaped component, the ventilation path from the heat exchanger being defrosted to the fan in heating operation is short, and the fan in heating operation would draw in air passing through the heat exchanger being defrosted. To prevent this, the plate-shaped component is provided.

[0004] JP 2009-085484 A

[0005] However, in the air conditioning unit of Patent Document 1, in addition to a structure such as a bell mouth for improving airflow near the fan, a plate-like component is provided solely for the purpose of reducing the amount of air drawn by the first fan from the second heat exchanger unit or the amount of air drawn by the second fan from the first heat exchanger unit. Patent Document 1 uses two propeller fans, one above the other, as the first fan and the other below. In such a configuration, a motor support extending vertically is typically disposed in the air passage within the main casing, and the fan motors of the two propeller fans are fixed to this motor support. Therefore, in the air conditioning unit of Patent Document 1, when providing a plate-like component to separate the air passage, significant structural modifications are required to avoid interference with obstacles such as the motor support.

[0006] The present disclosure has been made against the background of the above-mentioned problems, and provides an air conditioning unit and a refrigeration cycle device that can reduce the amount of air drawn by one blower from a heat exchanger section facing the other blower, using a structure that is less functionally wasteful than conventional structures.

[0007] The air conditioning unit of the present disclosure comprises a housing having an air intake and an air outlet, a first heat exchanger and a second heat exchanger arranged side by side along the inner surface of the housing, each facing the air intake, and a first blower arranged side by side inside the housing, facing the first heat exchanger and a second blower facing the second heat exchanger, wherein the first blower has a centrifugal first fan and a first casing that houses the first fan to form an air passage for the first fan and has an air intake surface with an air intake opening formed therein that is arranged along the first heat exchanger, and the second blower has a centrifugal second fan and a second casing that houses the second fan to form an air passage for the second fan and has an air intake surface with an air intake opening formed therein that is arranged along the second heat exchanger.

[0008] In the air conditioning unit of the present disclosure, each blower is a centrifugal blower and has a casing that houses the fan, with the suction surface of the casing aligned with the heat exchanger facing the blower. Therefore, the casing that forms the air passage in each centrifugal blower makes the length of the airflow path from the second heat exchanger to the first fan and the length of the airflow path from the first heat exchanger to the second fan longer than in the past, thereby reducing the airflow that takes up such airflow paths. As a result, compared to the conventional configuration in which a new, functionally unnecessary plate-like component is added, the air passages are separated by a functionally less wasteful structure, and the amount of air drawn by one blower from the heat exchanger facing the other blower can be reduced.

[0009] 1. A circuit diagram showing a refrigeration cycle apparatus according to embodiment 1.

[0023] FIG. 1 is a circuit diagram showing a refrigerant flow when a heating / defrosting operation is being performed in the refrigeration cycle apparatus of FIG. 1.

[0024] FIG. 2 is a perspective view showing the appearance of an air conditioning unit according to embodiment 1.

[0025] FIG. 3 is a schematic view showing an example of the configuration of the heat exchanger of FIG. 1.

[0026] FIG. 4 is a schematic view showing another example of the configuration of the heat exchanger of FIG. 1.

[0027] FIG. 5 is a schematic view showing yet another example of the configuration of the heat exchanger of FIG. 1.

[0028] FIG. 6 is a vertical cross-sectional view schematically showing the air conditioning unit of FIG. 3.

[0029] FIG. 7 is a horizontal cross-sectional view schematically showing the A-A cross section of the air conditioning unit of FIG. 10.

[0030] FIG. 8 is a perspective view schematically showing the internal configuration of the blower chamber in the air conditioning unit of FIG. 3.

[0031] FIG. 9 is a rear perspective view schematically showing the blower of FIG. 12.

[0032] FIG. 11 is a front view schematically showing the air conditioning unit of FIG. 3 with the blower chamber front panel removed. 16. FIG. 17 is an explanatory diagram showing the flow of air in a state in which one of the fans in the air conditioning unit of FIG. 10 is stopped. FIG. 18 is a vertical cross-sectional view schematically showing an air conditioning unit according to a modified example of embodiment 1. FIG. 19 is a perspective view schematically showing the internal configuration of the blower chamber in the air conditioning unit of FIG. 16. FIG. 19 is a vertical cross-sectional view schematically showing an air conditioning unit according to embodiment 2. FIG. 20 is a vertical cross-sectional view schematically showing an air conditioning unit according to embodiment 3. FIG. 21 is a vertical cross-sectional view schematically showing an air conditioning unit according to a first modified example of embodiment 3. FIG. 22 is a vertical cross-sectional view schematically showing an air conditioning unit according to a second modified example of embodiment 3. FIG. 23 is a vertical cross-sectional view schematically showing an air conditioning unit according to embodiment 4. FIG. 24 is a circuit diagram showing a refrigeration cycle apparatus according to embodiment 5.

[0010] Hereinafter, an embodiment in which a refrigeration cycle apparatus according to the present disclosure is applied to an air conditioner and an air conditioning unit of the refrigeration cycle apparatus is an outdoor unit of the air conditioner will be described with reference to the drawings. The present disclosure is not limited to the following embodiments and can be modified in various ways without departing from the spirit of the present disclosure. Furthermore, the present disclosure includes all possible combinations of the configurations shown in the following embodiments. In particular, the combinations of components are not limited to the combinations in each embodiment, and components described in one embodiment can be applied to another embodiment. The air conditioning unit shown in the drawings is an example of an air conditioning unit of the present disclosure, and the refrigeration cycle apparatus shown in the drawings is an example of a refrigeration cycle apparatus of the present disclosure. However, the present disclosure is not limited to the configurations shown in the drawings. Furthermore, in the following description, directional terms (e.g., "up," "down," "right," "left," "front," "rear," etc.) are used as appropriate to facilitate understanding, but these are for explanatory purposes and do not limit the present disclosure. Unless otherwise specified, these directional terms refer to the direction when the air conditioning unit is viewed from the front (front side). In addition, in each drawing, the same reference numerals are used to denote the same or equivalent parts, and this is common throughout the specification. Note that in each drawing, the relative dimensions or shapes of each component may differ from those of the actual parts.

[0011] Embodiment 1. Figure 1 is a circuit diagram showing a refrigeration cycle apparatus 100 according to embodiment 1. In Figure 1, solid arrows indicate the direction of refrigerant flow during heating operation, and dashed arrows indicate the direction of refrigerant flow during cooling operation. The configuration of the refrigeration cycle apparatus 100 according to embodiment 1 will be described with reference to Figure 1.

[0012] The refrigeration cycle apparatus 100 is an air conditioning apparatus that adjusts the air in, for example, a room that is a space to be air-conditioned, and as shown in Fig. 1, includes an air conditioning unit 70 applied to an outdoor unit and an indoor unit 60. The air conditioning unit 70 is connected to the indoor unit 60 by a connecting pipe RP to form a refrigeration cycle.

[0013] The air conditioning unit 70 includes a compressor 5, a flow switching device 6, an outdoor heat exchanger 1, an accumulator 4, expansion devices 8 (8a, 8b), an outdoor blower 2, flow control devices 12 (12a, 12b), and a bypass circuit 9 (9a, 9b). The air conditioning unit 70 also includes a control device 15 that controls the refrigeration cycle. The indoor unit 60 includes an indoor heat exchanger 3 and an indoor blower 11.

[0014] In the first embodiment, it is defined that one outdoor heat exchanger 1 is disposed in the air conditioning unit 70. The outdoor heat exchanger 1 includes a first heat exchanger 10a and a second heat exchanger 10b, and the outdoor blower 2 includes a first blower 20a and a second blower 20b. Hereinafter, the first heat exchanger 10a and the second heat exchanger 10b may be referred to simply as heat exchangers 10 without distinction. Furthermore, the first blower 20a and the second blower 20b may be referred to simply as blowers 20 without distinction. Note that the number of heat exchangers 10 constituting the outdoor heat exchanger 1 and the number of blowers 20 mounted in the air conditioning unit 70 may be three or more.

[0015] The compressor 5, flow switching device 6, indoor heat exchanger 3, throttling devices 8 (8a, 8b), outdoor heat exchanger 1 (first heat exchanger 10a, second heat exchanger 10b), flow control devices 12 (12a, 12b), and accumulator 4 are connected by a main pipe 41 and branch pipes 42 (42a, 42b) to form a main circuit 40 through which the refrigerant circulates. In the main circuit 40, the flow control device 12a, the first heat exchanger 10a, and the throttling device 8a are connected in series by the branch pipe 42a, and the flow control device 12b, the second heat exchanger 10b, and the throttling device 8b are connected in series by the branch pipe 42b, and these are connected in parallel with each other. The refrigerant circuit C of the refrigeration cycle apparatus 100 is composed of this main circuit 40 and bypass circuits 9 (9a, 9b), which will be described later.

[0016] The compressor 5 draws in a low-temperature, low-pressure refrigerant, compresses the drawn refrigerant, and discharges a high-temperature, high-pressure refrigerant. The compressor 5 is, for example, an inverter compressor whose capacity, which is the amount of refrigeration per unit time, is controlled by changing the operating frequency.

[0017] The flow path switching device 6 is, for example, a four-way valve that switches the direction of the refrigerant flow to switch between cooling operation and heating operation. Note that the flow path switching device 6 may be a combination of a two-way valve and a three-way valve instead of a four-way valve.

[0018] The first heat exchanger 10a and the second heat exchanger 10b are configured to operate independently of each other and are used to exchange heat between the refrigerant and outdoor air, for example, and function as a condenser during cooling operation and as an evaporator during heating operation.

[0019] The outdoor blower 2 is provided near the outdoor heat exchanger 1 and sends outdoor air to the outdoor heat exchanger 1. Specifically, a first blower 20a is provided near the first heat exchanger 10a, and outdoor air drawn in by the first blower 20a passes through the first heat exchanger 10a. A second blower 20b is provided near the second heat exchanger 10b, and outdoor air drawn in by the second blower 20b passes through the second heat exchanger 10b. Each of the first blower 20a and the second blower 20b is configured using a centrifugal blower such as a sirocco fan, a turbo fan, or a radial fan. The air volume of each blower 20 is controlled by changing the fan rotation speed. The first blower 20a and the second blower 20b are configured so that the fan rotation speed can be controlled independently, thereby enabling the airflow (operation and stoppage, or air volume) to the first heat exchanger 10a and the second heat exchanger 10b to be controlled individually.

[0020] The expansion devices 8 (8a, 8b) reduce the pressure of the refrigerant to expand it. The expansion devices 8 (8a, 8b) are, for example, electronic expansion valves that can adjust the aperture, and by adjusting the aperture, the pressure of the refrigerant flowing into the indoor heat exchanger 3 is controlled during cooling operation, and the pressure of the refrigerant flowing into the outdoor heat exchanger 1 is controlled during heating operation.

[0021] The accumulator 4 is provided on the intake side of the compressor 5 and serves to store excess refrigerant that occurs due to differences in operating conditions between cooling and heating, or excess refrigerant that occurs due to transient changes in operation.

[0022] The flow rate control device 12a is provided in the branch pipe 42a and adjusts the amount of refrigerant flowing through the branch pipe 42a. The flow rate control device 12b is provided in the branch pipe 42b and adjusts the amount of refrigerant flowing through the branch pipe 42b. The flow rate control devices 12 (12a, 12b) may be any device that can at least open and close a flow path, and may be, for example, a solenoid valve or a two-way valve.

[0023] The bypass circuit 9 (9a, 9b) includes a bypass pipe 91 (91a, 92b) and a bypass flow control device 13 (13a, 13b). The bypass circuit 9a is a circuit that allows a portion of the refrigerant discharged from the compressor 5 to flow from the main pipe 41 between the compressor 5 and the flow switching device 6 to the branch pipe 42a between the first heat exchanger 10a and the flow control device 12a. The bypass circuit 9b is a circuit that allows a portion of the refrigerant discharged from the compressor 5 to flow from the main pipe 41 between the compressor 5 and the flow switching device 6 to the branch pipe 42b between the second heat exchanger 10b and the flow control device 12b.

[0024] The bypass pipe 91a connects the main pipe 41 between the compressor 5 and the flow path switching device 6 to the branch pipe 42a between the first heat exchanger 10a and the flow control device 12a. The bypass pipe 91b connects the main pipe 41 between the compressor 5 and the flow path switching device 6 to the branch pipe 42b between the second heat exchanger 10b and the flow control device 12b.

[0025] The bypass flow rate control device 13a is provided in the bypass pipe 91a and controls the amount of refrigerant flowing through the bypass pipe 91a. The bypass flow rate control device 13b is provided in the bypass pipe 91b and controls the amount of refrigerant flowing through the bypass pipe 91b. The bypass flow rate control devices 13 (13a, 13b) may be any device that can at least open and close a flow path, and may be, for example, a solenoid valve or a two-way valve.

[0026] The indoor heat exchanger 3 exchanges heat between the refrigerant and the air in a room that is a space to be air-conditioned, for example, and acts as an evaporator during cooling operation and as a condenser during heating operation.

[0027] The indoor blower 11 is provided near the indoor heat exchanger 3 and sends indoor air to the indoor heat exchanger 3 .

[0028] Here, examples of the refrigerant that can be used to circulate through the refrigerant circuit C include fluorocarbon refrigerants and HFO refrigerants. Examples of fluorocarbon refrigerants include HFC refrigerants such as R32, R125, and R134a. Examples of mixed refrigerants of HFC refrigerants include R410A, R407c, and R404A. Examples of HFO refrigerants include HFO-1234yf, HFO-1234ze(E), and HFO-1234ze(Z). Other refrigerants include CO ２ The refrigerant may be a mixture of the above refrigerants, such as a refrigerant, an HC refrigerant, an ammonia refrigerant, or a mixture of R32 and HFO-1234yf, or a refrigerant used in a vapor compression heat pump circuit. Examples of the HC refrigerant include propane and isobutane.

[0029] The control device 15 controls the actuator according to the operation mode, the required amount of heat exchange, etc. The control device 15 is composed of dedicated hardware or a CPU (also called a central processing unit, processing device, arithmetic unit, microprocessor, microcomputer, or processor) that executes a program stored in a storage device. When the control device 15 is dedicated hardware, the control device 15 corresponds to, for example, a single circuit, a composite circuit, an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), or a combination thereof. Each functional unit realized by the control device 15 may be realized by separate hardware, or each functional unit may be realized by a single piece of hardware.

[0030] When the control device 15 is a CPU, each function executed by the control device 15 is realized by software, firmware, or a combination of software and firmware. The software and firmware are written as programs and stored in a storage device. The CPU realizes each function by reading and executing the programs stored in the storage device. Note that some of the functions of the control device 15 may be realized by dedicated hardware, and other functions may be realized by software or firmware. The storage device may be configured as a hard disk, or may be configured as a volatile storage device such as random access memory (RAM) that can temporarily store data. The storage device may also be configured as a non-volatile storage device such as flash memory that can store data long-term. Note that, although the first embodiment illustrates a case in which the control device 15 is provided in the air conditioning unit 70, this is not particularly limited. The control device 15 may be provided in the indoor unit 60, for example. Alternatively, a control device with separate functions may be provided in the air conditioning unit 70 and the indoor unit 60.

[0031] The refrigeration cycle apparatus 100 has three operation modes: a cooling operation mode, a normal heating operation mode, and a heating / defrosting operation mode. As shown in Fig. 1, the cooling operation mode is a mode in which the indoor unit 60 performs a cooling operation, in which the outdoor heat exchanger 1 functions as a condenser, and the indoor unit 60 cools the room. The normal heating operation mode is a mode in which the indoor unit 60 performs a heating operation, in which the outdoor heat exchanger 1 functions as an evaporator, and the indoor unit 60 heats the room.

[0032] FIG. 2 is a circuit diagram showing the refrigerant flow during the heating / defrosting operation in the refrigeration cycle apparatus 100 of FIG. 1 . In FIG. 2 , solid arrows indicate the refrigerant flow direction during the heating / defrosting operation. As shown in FIG. 2 , the heating / defrosting operation mode is a mode in which the indoor unit 60 performs heating operation. In this mode, a portion of the outdoor heat exchanger 1 is defrosted. That is, one of the first heat exchanger 10a and the second heat exchanger 10b is defrosted, and the other acts as an evaporator, and the indoor unit 60 heats the room. In this manner, the heating / defrosting operation mode is an operation mode in which one of the first heat exchanger 10a and the second heat exchanger 10b acts as an evaporator while the other is defrosted, thereby maintaining heating operation while defrosting. That is, in the heating / defrosting operation mode, refrigerant is controlled to flow in opposite directions through the first heat exchanger 10a and the second heat exchanger 10b that constitute the outdoor heat exchanger 1.

[0033] In the heating / defrosting operation mode, the first heat exchanger 10a and the second heat exchanger 10b are alternately defrosted. For example, in the heating / defrosting operation mode, one of the first heat exchanger 10a and the second heat exchanger 10b functions as an evaporator to perform heating operation while the other heat exchanger 10b is defrosted. Then, in the heating / defrosting operation mode, when the defrosting of the other heat exchanger is completed, the other heat exchanger functions as an evaporator to perform heating operation while the other heat exchanger is defrosted. The heating / defrosting operation mode is performed when frost forms on the first heat exchanger 10a and the second heat exchanger 10b during normal heating operation. The heating / defrosting mode may be switched to when the drive frequency of the compressor 5 becomes lower than a frequency threshold.

[0034] <Cooling Operation Mode> Next, a description will be given of the flow of refrigerant in the refrigeration cycle apparatus 100 in the cooling operation mode. In the cooling operation mode, the flow path switching device 6 is switched as shown by the dashed lines in Fig. 1, so that the discharge side of the compressor 5 is connected to the first heat exchanger 10a and the second heat exchanger 10b, and the suction side of the compressor 5 is connected to the indoor heat exchanger 3. In addition, the flow control devices 12a and 12b are open, and the bypass flow control devices 13a and 13b are closed.

[0035] The compressor 5 compresses the refrigerant it draws in and discharges the refrigerant in a high-temperature, high-pressure gas state. The high-temperature, high-pressure gas refrigerant discharged from the compressor 5 passes through the flow switching device 6, where it branches, and then passes through the flow control devices 12a and 12b, respectively, before flowing into the first heat exchanger 10a and the second heat exchanger 10b, which function as condensers. In the first heat exchanger 10a, the refrigerant exchanges heat mainly with outdoor air sent by the first fan 20a, condensing and liquefying the refrigerant into a medium-temperature, high-pressure liquid state. In the second heat exchanger 10b, the refrigerant exchanges heat mainly with outdoor air sent by the second fan 20b, condensing and liquefying the refrigerant into a medium-temperature, high-pressure liquid state. The medium-temperature, high-pressure liquid refrigerants condensed in the first heat exchanger 10a and the second heat exchanger 10b flow into the expansion devices 8a and 8b, respectively. The medium-temperature, high-pressure liquid refrigerant that flows into the expansion devices 8a and 8b expands and decompresses in the expansion devices 8a and 8b, becoming a low-temperature, low-pressure, two-phase gas-liquid refrigerant. The two-phase gas-liquid refrigerant merges and flows into the indoor heat exchanger 3, which functions as an evaporator. In the indoor heat exchanger 3, the refrigerant exchanges heat with indoor air sent by the indoor blower 11, evaporating and gasifying. This cools the indoor air, cooling the room. The evaporated low-temperature, low-pressure gas refrigerant passes through the flow switching device 6 and the accumulator 4 and is drawn into the compressor 5.

[0036] <Normal Heating Operation Mode> Next, a description will be given of the flow of refrigerant in the refrigeration cycle apparatus 100 in the heating operation mode. In the heating operation mode, the flow path switching device 6 is switched as shown by the solid line in Fig. 1, so that the discharge side of the compressor 5 is connected to the indoor heat exchanger 3, and the suction side of the compressor 5 is connected to the first heat exchanger 10a and the second heat exchanger 10b. In addition, the flow control devices 12a and 12b are open, and the bypass flow control devices 13a and 13b are closed.

[0037] The compressor 5 compresses the refrigerant it draws in and discharges it in a high-temperature, high-pressure gas state. The high-temperature, high-pressure gas refrigerant discharged from the compressor 5 passes through the flow switching device 6 and flows into the indoor heat exchanger 3, which functions as a condenser. In the indoor heat exchanger 3, the refrigerant exchanges heat with the indoor air sent by the indoor blower 11, condensing and liquefying it, becoming a medium-temperature, high-pressure liquid refrigerant. At this time, the indoor air is heated, providing heating within the room. The condensed medium-temperature, high-pressure liquid refrigerant branches and flows into the throttling devices 8a and 8b, respectively. The medium-temperature, high-pressure refrigerant that flows into the throttling devices 8a and 8b expands and decompresses, becoming a medium-pressure, two-phase gas-liquid refrigerant. The two-phase gas-liquid refrigerant flows into the first heat exchanger 10a and the second heat exchanger 10b, which function as evaporators, respectively. In the first heat exchanger 10a, the refrigerant exchanges heat mainly with the outdoor air sent by the first fan 20a, evaporating and gasifying. In the second heat exchanger 10b, the refrigerant exchanges heat mainly with the outdoor air sent by the second fan 20b, evaporating and gasifying. The low-temperature, low-pressure gaseous refrigerants evaporated in the first heat exchanger 10a and the second heat exchanger 10b pass through the flow control devices 12a and 12b, respectively, and merge. Then, they pass through the flow switching device 6 and the accumulator 4, and are drawn into the compressor 5.

[0038] <Heating / Defrosting Operation Mode> Next, the flow of refrigerant in the refrigeration cycle apparatus 100 in the heating / defrosting operation mode will be described. During the heating / defrosting operation mode, the flow path switching device 6 is switched as shown by the solid lines in FIG. 2 , connecting the discharge side of the compressor 5 to the indoor heat exchanger 3 and the suction side of the compressor 5 to the first heat exchanger 10a and the second heat exchanger 10b. In the heating / defrosting operation mode, one of the first heat exchanger 10a and the second heat exchanger 10b is selected as the defrosting target and defrosts, while the other acts as an evaporator to continue the heating operation. The open / closed states of the flow control devices 12a and 12b, and the bypass flow control devices 13a and 13b are alternately switched, so that the defrosting target alternates between the first heat exchanger 10a and the second heat exchanger 10b. The flow of the refrigerant is switched by switching between the first heat exchanger 10a or the second heat exchanger 10b to be defrosted and the first heat exchanger 10a or the second heat exchanger 10b acting as an evaporator.

[0039] 2, a case where the second heat exchanger 10b is selected as the defrosting target will be described as an example. That is, the second heat exchanger 10b functions as a condenser to perform defrosting, and the first heat exchanger 10a functions as an evaporator to continue heating. In this case, the flow control device 12a and the bypass flow control device 13b are open, and the flow control device 12b and the bypass flow control device 13a are closed.

[0040] First, the flow of refrigerant related to heating will be described. The compressor 5 compresses the refrigerant it draws in and discharges the refrigerant in a high-temperature, high-pressure gas state. A portion of the high-temperature, high-pressure refrigerant discharged from the compressor 5 passes through the flow switching device 6 and flows into the indoor heat exchanger 3, which functions as a condenser. In the indoor heat exchanger 3, the refrigerant exchanges heat with indoor air sent by the indoor blower 11, condensing and liquefying it, becoming a medium-temperature, high-pressure liquid refrigerant. The condensed medium-temperature, high-pressure liquid refrigerant flows into the throttling device 8a. The medium-temperature, high-pressure refrigerant that flows into the throttling device 8a expands and decompresses, becoming a medium-pressure, two-phase gas-liquid refrigerant. The two-phase gas-liquid refrigerant does not flow into the second heat exchanger 10b, which is the defrosting target, but instead flows into the first heat exchanger 10a, which functions as an evaporator. In the first heat exchanger 10a, the refrigerant exchanges heat with outdoor air sent by the first blower 20a, evaporating and gasifying. The evaporated refrigerant in a low-temperature, low-pressure gas state passes through the flow rate control device 12 a, the flow path switching device 6 , and the accumulator 4 and is sucked into the compressor 5 .

[0041] Next, the flow of refrigerant during defrosting will be described. A portion of the high-temperature, high-pressure gaseous refrigerant discharged from the compressor 5 flows into the bypass pipe 91b without passing through the flow switching device 6. The refrigerant flowing into the bypass pipe 91b passes through the bypass flow control device 13b and flows into the second heat exchanger 10b, which is the defrost target. The refrigerant flowing into the second heat exchanger 10b is cooled by heat exchange with frost adhering to the second heat exchanger 10b. In this way, the high-temperature, high-pressure gaseous refrigerant discharged from the compressor 5 flows into the second heat exchanger 10b, melting the frost adhering to the second heat exchanger 10b. The supply of outdoor air to the second heat exchanger 10b, which is the defrost target, is stopped. That is, the second blower 20b opposite the second heat exchanger 10b is stopped. This prevents a decrease in defrosting efficiency due to cold air flowing into the second heat exchanger 10b, which is the defrost target. The second heat exchanger 10b is defrosted, and the refrigerant flowing out of the second heat exchanger 10b passes through the expansion device 8b and merges with the medium-temperature, high-pressure liquid refrigerant condensed in the indoor heat exchanger 3.

[0042] On the other hand, when the first heat exchanger 10a is selected as the defrost target, the first heat exchanger 10a functions as a condenser to defrost, and the second heat exchanger 10b functions as an evaporator to continue heating. In this case, the flow control device 12b and the bypass flow control device 13a are open, and the flow control device 12a and the bypass flow control device 13b are closed. Furthermore, the supply of outdoor air to the first heat exchanger 10a to be defrosted is stopped. That is, the first blower 20a opposite the first heat exchanger 10a is stopped. This prevents a decrease in defrosting efficiency due to cold air flowing through the first heat exchanger 10a to be defrosted.

[0043] The refrigeration cycle apparatus 100 is not limited to the above configuration. For example, the circuit configuration may be any configuration in which the first heat exchanger 10a and the second heat exchanger 10b can independently switch their operating states, and the bypass circuit 9 (9a, 9b) may be omitted from the refrigerant circuit C. Furthermore, the flow path switching device 6 and the accumulator 4 may be omitted from the refrigerant circuit C, and the refrigeration cycle apparatus 100 may be a dedicated cooling or heating machine.

[0044] When the bypass circuit 9 (9a, 9b) is omitted, the heating / defrosting operation mode cannot be implemented. However, the operating states of the first heat exchanger 10a and the second heat exchanger 10b can be differentiated in the cooling operation mode or the normal heating operation mode, for example, as follows. That is, by closing one of the flow control devices 12a and 12b, refrigerant is prevented from flowing through the corresponding branch pipe 42 (branch pipe 42a or branch pipe 42b). Then, the operation of the blower 20 (first blower 20a or second blower 20b) opposite the heat exchanger 10 (first heat exchanger 10a or second heat exchanger 10b) provided in the corresponding branch pipe 42 is stopped. Hereinafter, such an operation is referred to as an individual operation. Such an individual operation may be implemented, for example, in the cooling operation mode or the normal heating operation mode, when the required heat exchange rate is smaller than a predetermined threshold. By performing such an operation (hereinafter referred to as individual operation), the product life of the heat exchanger 10, the blower 20, etc. is extended.

[0045] Fig. 3 is a perspective view showing the appearance of the air conditioning unit 70 according to the first embodiment. The schematic configuration of the air conditioning unit 70 will be described below with reference to Fig. 3. In the figure, the arrow X direction represents the width direction of the air conditioning unit 70, the arrow Y direction represents the depth direction of the air conditioning unit 70, and the arrow Z direction represents the height direction of the air conditioning unit 70. Furthermore, in the figure, the outline arrows represent the direction of air flow.

[0046] As shown in Fig. 3, the air conditioning unit 70 has a housing 79 that forms an outer shell, and the outdoor blower 2, compressor 5, etc. are disposed within the housing 79. The interior of the housing 79 is partitioned into a machine chamber M that houses the compressor 5, etc., and an air blower chamber F that houses the outdoor blower 2, etc. The machine chamber M also houses refrigerant piping (not shown), a control device 15, etc. The control device 15 is disposed above the compressor 5. The outdoor heat exchanger 1 is disposed in the air blower chamber F, facing the outdoor blower 2.

[0047] The housing 79 is formed with an inlet 79i and an outlet 79o, which are openings through which air passes. The housing 79 has a rectangular parallelepiped shape and includes a top plate 71 that forms the upper surface, a bottom plate 72 that forms the lower surface, an air blower chamber front panel 74 that forms the portion of the front surface facing the air blower chamber F, and a machine chamber panel 73. The machine chamber panel 73 forms the right side surface of the housing 79, the portion of the front surface of the housing 79 that faces the machine chamber M, and the portion of the back surface of the housing 79 that faces the machine chamber M. The inlet 79i is provided in the portion of the back surface of the housing 79 that faces the air blower chamber F, and the outlet 79o is provided in the left side surface and the left side of the right side surface of the housing 79 that faces the air blower chamber F.

[0048] In the present disclosure, a centrifugal blower is used as blower 20, and therefore, in housing 79, outlet 79o is provided on a surface perpendicular to the surface on which inlet 79i is provided. Specifically, outlet 79o is provided on the left side surface of housing 79, perpendicular to the back surface on which inlet 79i is provided. Air conditioning unit 70 according to embodiment 1 has inlet 79i only on the back surface of housing 79, and no inlet 79i is provided on blower chamber front panel 74, resulting in a one-sided inlet configuration.

[0049] 3 shows the housing 79 without a left side panel, a frame-shaped left side panel may be provided. The intake port 79i is formed in the left side panel at a portion facing an outlet opening 21o (described later) of the blower 20. The housing 79 is preferably configured so that airflow is not drawn into the blower chamber F from any source other than the outdoor heat exchanger 1.

[0050] When viewed from the front, the air blower chamber F has a rectangular shape that is long in the height direction of the air conditioning unit 70 (direction of arrow Z), and a first fan 20a and a second fan 20b are arranged vertically inside the air blower chamber F. The first heat exchanger 10a is arranged behind the first fan 20a, and the second heat exchanger 10b is arranged behind the second fan 20b. The first heat exchanger 10a and the second heat exchanger 10b are arranged vertically inside the housing 79 along the back surface of the housing 79, and each faces an air intake 79i.

[0051] The shape of the air blower chamber F and the arrangement direction of the fans 20 are not limited to the above. For example, the air blower chamber F may be formed in a rectangular shape that is long in the width direction (arrow X direction) when viewed from the front, and the first fan 20a and the second fan 20b may be arranged side by side on the left and right within the air blower chamber F. The number of fans 20 housed in the air blower chamber F may be three or more. For example, three fans 20 may be arranged in the vertical direction (arrow Z direction) within the air blower chamber F, and a heat exchanger 10 may be provided facing each fan 20.

[0052] FIG. 4 is a schematic diagram showing one configuration example of the heat exchanger 10 of FIG. 1 . FIG. 5 is a schematic diagram showing another configuration example of the heat exchanger 10 of FIG. 1 . FIG. 6 is a schematic diagram showing yet another configuration example of the heat exchanger 10 of FIG. 1 . FIG. 7 is a diagram showing an example of the cross-sectional shape of the heat transfer tube 45 in the heat exchanger 10 of FIG. 1 . FIG. 8 is a diagram showing another example of the cross-sectional shape of the heat transfer tube 45 in the heat exchanger 10 of FIG. 1 . FIG. 9 is a diagram showing yet another example of the cross-sectional shape of the heat transfer tube 45 in the heat exchanger 10 of FIG. 1 . Hereinafter, the configuration of the heat exchanger 10 (first heat exchanger 10a, second heat exchanger 10b) will be described with reference to FIGS. 4 to 9 .

[0053] 4 to 6, the heat exchanger 10 includes a plurality of heat transfer tubes 45 arranged with gaps G between them. As shown in FIGS. 4 to 6, the heat exchanger 10 has a substantially rectangular shape, and is configured so that air passes through the gaps G as indicated by the outline arrows in FIGS.

[0054] In the heat exchanger 10, the heat transfer tubes 45 may extend in the X direction as shown in FIG. 4 or in the Z direction as shown in FIGS. 5 and 6. Alternatively, the heat transfer tubes 45 may be provided so as to penetrate through the fins 46 as shown in FIG. 4. The fins 46 shown in FIG. 4 are so-called plate fins. Alternatively, a fin 46 may be provided between a pair of heat transfer tubes 45 as shown in FIG. 5. The fins 46 shown in FIG. 5 are so-called corrugated fins. Alternatively, the heat exchanger 10 may be a so-called finless heat exchanger that does not have fins as shown in FIG. 6.

[0055] 5 and 6 , the heat exchanger 10 may include a first header 50 and a second header 51 disposed on either side of the heat transfer tubes 45 in the extension direction. The first header 50 and the second header 51 distribute the refrigerant to the heat transfer tubes 45 and merge the refrigerant after heat exchange with air in each heat transfer tube 45. The first header 50 extends in the arrangement direction of the heat transfer tubes 45 (the direction of the arrow X). One ends of the heat transfer tubes 45 are connected to the first header 50. A first inlet / outlet pipe 52 is connected to one end of the first header 50 in the extension direction. The second header 51 extends in the arrangement direction of the heat transfer tubes 45 (the direction of the arrow X). The other ends of the heat transfer tubes 45 are connected to the second header 51. A second inlet / outlet pipe 53 is connected to one end of the second header 51 in the extension direction.

[0056] The cross-sectional shape of the heat transfer tube 45 is not particularly limited. For example, the cross section of the heat transfer tube 45 may be circular as shown in Fig. 7 , or may be a rectangular or substantially rectangular flattened shape having a longitudinal direction and a lateral direction as shown in Fig. 8 . Fig. 8 shows an example of a multi-hole flattened tube in which holes 45h serving as multiple flow paths are provided inside the flattened heat transfer tube 45. The heat transfer tube 45 may also be configured with protrusions 45p protruding outward as shown in Fig. 9 .

[0057] The first heat exchanger 10a and the second heat exchanger 10b may have the same configuration or different configurations.

[0058] FIG. 10 is a vertical cross-sectional view schematically illustrating the air conditioning unit 70 of FIG. 3. FIG. 11 is a horizontal cross-sectional view schematically illustrating the A-A cross section of the air conditioning unit 70 of FIG. 10. FIG. 12 is a perspective view schematically illustrating the internal configuration of the air blower chamber F in the air conditioning unit 70 of FIG. 3. In FIG. 12, the top plate 71, bottom plate 72, and air blower chamber front panel 74 shown in FIG. 3 are omitted. FIG. 13 is a rear perspective view schematically illustrating the air blower 20 of FIG. 12. FIG. 14 is a front view schematically illustrating the air conditioning unit 70 of FIG. 3 with the air blower chamber front panel 74 removed. Below, the configuration of the air blower chamber F and the air blower 20, the positional relationship between the air blower 20 and the heat exchanger 10, and the arrangement of the wiring P of the air blower 20 will be described in detail with reference to FIGS. 10 to 14.

[0059] 11 and 12, the housing 79 includes a partition plate 75 installed on the bottom plate 72 (see FIG. 10), which separates the machine chamber M from the air blowing chamber F. As shown in FIGS. 10 and 11, the right side, front side, upper side, and lower side of the air blowing chamber F are covered by the partition plate 75, the air blowing chamber front panel 74, and portions of the top plate 71 and the bottom plate 72 that are closer to the air outlet 79o than the partition plate 75. The rear side of the air blowing chamber F is defined as an intake port 79i, and the left side of the air blowing chamber F is defined as an air outlet 79o. Hereinafter, the portions of the housing 79 that separate the air blowing chamber F (the above-mentioned partition plate 75, the air blowing chamber front panel 74, and the left portions of the top plate 71 and the bottom plate 72) may be referred to as the air blowing chamber wall surface Wf.

[0060] As shown in FIG. 13, each blower 20 includes a centrifugal fan 22, a casing 21 that houses the fan 22 and forms an air passage for the fan 22, and a fan motor 23 that drives the fan 22 to rotate.

[0061] The fan 22 is, for example, an impeller 22r including a main plate, a plurality of blades provided on the main plate, and a shroud provided to sandwich the plurality of blades between the main plate and the impeller 22r. The fan 22 may be configured with a plurality of impellers 22r connected in the axial direction, and these plurality of impellers 22r may be rotationally driven by a common fan motor 23.

[0062] 11 and 13, the casing 21 is disposed to surround the outer periphery of the fan 22, improving airflow near the fan 22 and ensuring a sufficient flow rate. The casing 21 of the fan 22 has a flat front wall 21f and a rear wall 21r facing each other, and a peripheral wall 21c connecting the outer peripheries of the front wall 21f and the rear wall 21r. An outlet opening 21o is formed in the peripheral wall 21c of the casing 21 in a portion facing the outlet 79o of the housing 79, and an inlet opening 21i is formed in the front wall 21f and the rear wall 21r of the casing 21 on the side facing the inlet 79i of the housing 79. Here, it is defined that the inlet opening 21i is formed in the rear wall 21r of the casing 21, and the outlet opening 21o is formed on the left side surface of the peripheral wall 21c (the right side in FIG. 13). 13, the suction opening 21i has a circular shape, and the outlet opening 21o has a rectangular shape. Although not shown, a bell mouth may be provided on the outer periphery of the suction opening 21i in the casing 21.

[0063] In the casing 21, the peripheral wall portion 21c is provided on the outer periphery of the fan 22, and its inner surface guides the air discharged in the centrifugal direction (i.e., toward the outer periphery) from the centrifugal fan 22 inside the casing 21 to the outlet opening 21o of the casing 21. Therefore, it is preferable that the portion of the peripheral wall portion 21c, particularly the portion opposite to the side where the outlet opening 21o is provided, be provided in a curved shape that fits along the fan 22.

[0064] 11 , fan motor 23 has a cylindrical motor body 23c and a motor shaft 23d rotatably supported by motor body 23c. In embodiment 1, fan motor 23 is a single-shaft fan motor in which a portion of motor shaft 23d protrudes from one side of motor body 23c, and fan 22 is attached to this protruding portion of motor shaft 23d. Motor body 23c is attached to casing 21 using fasteners (not shown), such as screws.

[0065] As shown in FIG. 11 , the casing 21 preferably has a depth large enough to accommodate not only the fan 22 but also the fan motor 23. In the first embodiment, the fan motor 23 is attached to the front wall 21f of the casing 21, the motor body 23c is disposed at the front side of the casing 21, and the motor shaft 23d extends rearward from the motor body 23c. By attaching the fan motor 23 to the wall (front wall 21f) opposite the suction surface Si (rear wall 21r) where the suction opening 21i is provided in the casing 21, the fan motor 23 is prevented from interfering with the intake of air. Alternatively, the motor body 23c may be provided so as to penetrate the front wall 21f, and the motor body 23c may also be supported by the blower chamber front panel 74.

[0066] As shown in FIG. 11, in the air conditioning unit 70, the blower 20 and the heat exchanger 10 are arranged so that the suction surface Si (rear wall portion 21r) of the casing 21 of the blower 20 faces the downstream side surface 10d of the heat exchanger 10.

[0067] When the blower 20 of the air conditioning unit 70 is operating, air flows from the outside of the housing 79 into the inside through the intake port 79i. The air that flows into the inside of the housing 79 passes through the gap G of the heat exchanger 10 and then flows into the casing 21 through the intake opening 21i of the blower 20. As the air that flows into the inside of the housing 79 passes through the gap G of the heat exchanger 10, it exchanges heat with the refrigerant flowing through the heat transfer tube 45 (see FIGS. 4 to 6 ) of the heat exchanger 10. The air that flows into the casing 21 of the blower 20 is pressurized by the fan 22 inside the casing 21 and discharged to the outer periphery, and is guided to the outlet opening 21o by the peripheral wall portion 21c. The air guided to the outlet opening 21o inside the casing 21 flows out of the casing 21 through the outlet opening 21o and then flows out of the air conditioning unit 70 through the outlet opening 79o of the housing 79.

[0068] 10 , of the two blowers 20, the upper first blower 20a faces the first heat exchanger 10a, and the lower second blower 20b faces the second heat exchanger 10b disposed below the first heat exchanger 10a. Hereinafter, the fan 22, casing 21, and fan motor 23 of the first blower 20a may be referred to as the first fan 22a, first casing 21a, and first fan motor 23a. Also, the fan 22, casing 21, and fan motor 23 of the second blower 20b may be referred to as the second fan 22b, second casing 21b, and second fan motor 23b.

[0069] The first casing 21a accommodates a first fan 22a therein and forms an air passage for the first fan 22a, and is disposed so that its suction surface Si is along the first heat exchanger 10a. The first blower 20a generates an airflow that passes through the first heat exchanger 10a when the first fan 22a is rotated by a first fan motor 23a. The second casing 21b accommodates a second fan 22b therein and forms an air passage for the second fan 22b, and is disposed so that its suction surface Si is along the second heat exchanger 10b. The second blower 20b generates an airflow that passes through the second heat exchanger 10b when the second fan 22b is rotated by a second fan motor 23b.

[0070] Each fan 20 is disposed near the opposing heat exchanger 10. The distance L between the opposing fan 20 and heat exchanger 10, i.e., the distance L between the suction surface Si of the casing 21 and the downstream side surface 10d of the heat exchanger 10 (see FIG. 11 ) in the depth direction (arrow Y direction), is preferably small in order to separate the air paths of the two fans 22.

[0071] 10 and 11 , in a configuration in which the intake opening 21i of the blower 20 is smaller than the heat exchanger 10, it is preferable to provide a small gap between the heat exchanger 10 and the blower 20. By providing this gap, air that has passed through a portion of the heat exchanger 10 that is on the outer periphery of the area facing the intake opening 21i can also flow into the casing 21, making it easier to ensure a sufficient air volume.

[0072] Each blower 20 is fixed inside the housing 79 so that the casing 21 does not move during operation. Specifically, the casing 21 of the blower 20 is fixed to a portion of the housing 79 other than the portion where the air inlet 79i is provided (i.e., the portion where the heat exchanger 10 is provided). In a configuration in which the air inlet 79i is provided on the rear side of the air blowing chamber F and the air outlet 79o is provided on the left side as shown in Figure 11, the casing 21 is fixed to the air blowing chamber wall surface Wf of the housing 79 (i.e., the partition plate 75, the air blowing chamber front panel 74, the left portion of the top plate 71, or the left portion of the bottom plate 72).

[0073] 14 , the lower second fan 20b may be fixed to the bottom plate 72 with a fixture 81a, and the upper first fan 20a may be fixed to the top plate 71 with a fixture 81b. Alternatively, the first fan 20a may be placed above the second fan 20b, and the casings 21 may be fixed to each other, and the lower second fan 20b may be fixed to the bottom plate 72, or the upper first fan 20a may be fixed to the top plate 71. The fixtures 81a and 81b may be fasteners such as screws. Note that the fixtures 81a and 81b may have a drawer structure such as a rail to facilitate easier maintenance and other operations.

[0074] The effects obtained by the air conditioning unit 70 of the present disclosure will be described below. In an air conditioning unit 70 equipped with multiple blowers 20, each blower 20 is a propeller fan, and in a conventional configuration in which the fan motor 23 of each blower 20 is located closer to the air intake 79i of the housing 79 than the impeller 22r, a motor support portion is required that is not necessary for forming an air path for the propeller fan. The motor support portion required in the conventional configuration extends in the arrangement direction (e.g., vertically) to support the fan motors 23 of the multiple propeller fans, and is provided between the blowers 20 and the air intake 79i of the housing 79. Therefore, the motor support portion obstructs the intake of air into the propeller fan, reducing the airflow.

[0075] In contrast, in the present disclosure, each of the two blowers 20 is a centrifugal blower and is configured to include a casing 21 that forms an air passage for the fan 22, so that the fan motor 23 can be attached to the casing 21 in each blower 20. That is, in each blower 20, the fan 22 can be supported by the casing 21 that forms the air passage for the fan 22, so that a decrease in air volume can be suppressed compared to a conventional configuration in which a motor support portion that is not necessary for forming an air passage is provided on the suction side.

[0076] Furthermore, in the present disclosure, the fan motor 23 of each blower 20 is fixed to the casing 21, allowing the fan 22 to be supported by the casing 21. Therefore, the casing 21, which forms the airflow path, can be extended to the vicinity of the heat exchanger 10, allowing air after heat exchange by the heat exchanger 10 to immediately flow into the casing 21. In conventional configurations, the distance between the heat exchanger and the front partition plate, on which bellmouths surrounding each of the two propeller fans are formed, is increased by the provision of a motor support portion. Furthermore, if a plate-like component (specifically, an extension of the bottom plate of the drain pan) is further provided between the two bellmouths to extend from the heat exchanger side across the motor support portion to the front partition plate to separate the airflow paths of the two propeller fans, there is a concern about interference between the components. In the present disclosure, the airflow paths of the two fans 22 can be separated with a structure that is less likely to cause interference between the components, making the design easier than with such conventional configurations.

[0077] 10 and 14, wiring P (wiring Pa, wiring Pb) extends from the fan motor 23 of each blower 20, and the wiring P is connected to the control device 15, for example, through a wiring hole 75h provided in the upper part of the partition plate 75. In the present disclosure, the blower 20 has a casing 21, and if the fan 22 and the fan motor 23 are arranged to be enclosed in the casing 21 as in the example of FIG. 10, the wiring P from the fan motor 23 can be routed along the casing 21 and guided to the top plate 71 or the partition plate 75.

[0078] 10 and 14, the fan motor 23 of each blower 20 is fixed to the surface (front wall 21f) opposite the suction surface Si of the casing 21. Therefore, the wiring P (wiring Pa, wiring Pb) of each blower 20 is routed along the front wall 21f of the casing 21, then routed along the top plate 71 or the partition plate 75, passed through the wiring hole 75h, and connected to the control device 15.

[0079] In the conventional configuration, the wiring P (wires Pa and Pb) of each propeller fan is routed upward to a common motor support portion provided between the propeller fans and the air inlet 79i of the housing 79, then routed to the top plate 71, passed through the wiring hole 75h, and connected to the control device 15. In this configuration, not only the motor support portion but also the wiring P is arranged on the air inlet side of the propeller fans. Therefore, when providing a plate-like component (an extension of the bottom plate of the drain pan) that separates the air passages of the two propeller fans, interference with the wiring P must be considered. Furthermore, the wiring P also hinders the air intake into the propeller fans, further reducing the airflow. In contrast, in the present disclosure, the wiring P is avoided from being arranged on the air inlet side of the blower 20, thereby suppressing the complication of the design and the reduction in airflow due to the wiring P of the blower 20.

[0080] <Explanation of Operation> Figure 15 is an explanatory diagram showing the flow of air in a state where one of the fans 20 is stopped in the air conditioning unit 70 of Figure 10. Hereinafter, the flow of air in the air conditioning unit 70 during operation of the refrigeration cycle apparatus 100 will be described with reference to Figures 1, 2, 10 to 12, and 15.

[0081] When the refrigeration cycle device 100 (see Figure 1) is performing, for example, cooling operation or heating operation, both the first fan 20a and the second fan 20b operate as shown in Figure 10, and heat exchange between the refrigerant and air occurs in both the first heat exchanger 10a and the second heat exchanger 10b.

[0082] In the upper first blower 20a, the first fan motor 23a is driven to rotate the first fan 22a, causing air to enter the housing 79 from the rear through the suction port 79i, pass through the upper first heat exchanger 10a, and exchange heat with the refrigerant as it passes. In the lower second blower 20b, the second fan motor 23b is driven to rotate the second fan 22b, causing air to enter the housing 79 from the rear through the suction port 79i, pass through the lower second heat exchanger 10b, and exchange heat with the refrigerant as it passes.

[0083] The air that has passed through the upper first heat exchanger 10a enters the first casing 21a through the intake opening 21i of the first blower 20a, which is disposed along the first heat exchanger 10a, is drawn into the first fan 22a, changes its direction of travel by approximately 90 degrees, and is exhausted to the outer periphery. The air exhausted from the first fan 22a to the outer periphery is guided to the left by the peripheral wall 21c of the first casing 21a (see FIG. 11), and is blown out of the air conditioning unit 70 through the outlet opening 21o of the first casing 21a and the outlet 79o of the housing 79 (see FIG. 12).

[0084] The air that has passed through the lower second heat exchanger 10b enters the second casing 21b through the intake opening 21i of the second blower 20b arranged along the second heat exchanger 10b, is sucked into the second fan 22b, changes its direction of travel by approximately 90 degrees, and is exhausted to the outer periphery. The air exhausted from the second fan 22b to the outer periphery is guided to the left by the peripheral wall 21c of the second casing 21b (see FIG. 11), and is blown out of the air conditioning unit 70 through the outlet opening 21o of the second casing 21b and the outlet 79o of the housing 79 (see FIG. 12).

[0085] When the refrigeration cycle apparatus 100 is performing, for example, a heating / defrosting operation (see FIG. 2), only one of the first fan 20a and the second fan 20b operates, as shown in FIG. 15. As shown in FIG. 2, during the heating / defrosting operation, one of the first heat exchanger 10a and the second heat exchanger 10b functions as an evaporator to continue heating, while the other is designated as a defrosting target and functions as a condenser. In the following description, it is defined that the first heat exchanger 10a continues heating, the first fan 20a operates, the second heat exchanger 10b is designated as a defrosting target, and the second fan 20b is stopped.

[0086] 15, while the upper first fan 20a is operating, air enters the housing 79 from the rear through the air inlet 79i, passes through the first heat exchanger 10a, and enters the first casing 21a through the air inlet 21i of the first fan 20a. Although the lower second fan 20b is stopped, a small amount of air may flow from the second heat exchanger 10b to the first fan 20a through the small gap between the first casing 21a and the first heat exchanger 10a due to the suction force of the first fan 22a. However, because the casing 21 of each fan 20 is disposed close to the heat exchanger 10a, the amount of air flowing through the second heat exchanger 10b is much smaller than the amount of air flowing through the first heat exchanger 10a. Even if air enters the housing 79 from the second heat exchanger 10b, the first casing 21a, which is provided up to the vicinity of the first heat exchanger 10a of the first fan 22a, prevents the air from taking the path indicated by the dashed white arrow in Fig. 15. Therefore, in order for the air from the second heat exchanger 10b to enter the air passage of the first fan 22a, it must pass through the gap between the first heat exchanger 10a and the first casing 21a, which makes the path longer, and therefore the air from the second heat exchanger 10b is less likely to be sucked into the first fan 22a.

[0087] In other words, by positioning the suction surface Si of each blower 20 near the corresponding heat exchanger 10, when some blowers 20 are operated and other blowers 20 are stopped, the amount of air passing through the heat exchanger 10 corresponding to the other blowers 20 can be reduced.

[0088] In the heating / defrosting operation, the flow of refrigerant in the second heat exchanger 10b to be defrosted is made opposite to the flow of refrigerant in the first heat exchanger 10a, and the blowing of air to the second heat exchanger 10b to be defrosted is stopped. Therefore, by separating the air paths of the two fans 22, in the heating / defrosting operation, it is possible to suppress a decrease in defrosting efficiency due to the flow of cold air to the second heat exchanger 10b to be defrosted.

[0089] Furthermore, in individual operation, which is performed when the required amount of heat exchange is small during cooling operation or normal heating operation, the flow of refrigerant in one of the heat exchangers 10 (for example, the second heat exchanger 10b) is stopped, and air is stopped from being sent to this heat exchanger 10. Therefore, by separating the air passages, in individual operation, it is possible to suppress a decrease in cooling or heating efficiency caused by outdoor air being drawn through the heat exchanger 10 (the second heat exchanger 10b) in which the refrigerant is not flowing.

[0090] As shown in Fig. 15, air that enters the first casing 21a through the intake opening 21i of the first blower 20a in operation is sucked into the first fan 22a, changes its direction of travel by approximately 90 degrees, and is exhausted to the outer periphery. As shown in Fig. 12, the air exhausted from the first fan 22a to the outer periphery is guided to the left by the peripheral wall portion 21c of the first casing 21a (see Fig. 12), and is blown out of the air conditioning unit 70 through the outlet opening 21o of the first casing 21a and the outlet 79o of the housing 79.

[0091] FIG. 16 is a vertical cross-sectional view schematically illustrating an air conditioning unit 70 according to a modified example of the first embodiment. FIG. 17 is a perspective view schematically illustrating the internal configuration of the blower chamber F in the air conditioning unit 70 of FIG. 16. In the example of FIG. 14 described above, the casings 21 (first casing 21a and second casing 21b) of the two blowers 20 provided in the air conditioning unit 70 are configured separately. However, in the modified example shown in FIGS. 16 and 17, the casings 21 (first casing 21a and second casing 21b) of the two blowers 20 are configured as an integrated unit. That is, the lower part of the first casing 21a arranged on the upper side and the upper part of the second casing 21b arranged on the lower side are configured to be connected.

[0092] The integrated casing 121 shown in Figures 16 and 17 is fixed within the housing 79, as in the example of Figure 14, but since the first casing 21a and the second casing 21b are connected, the number of fixing points (not shown) to the housing 79 can be reduced.

[0093] As described above, the air conditioning unit 70 according to the first embodiment includes a housing 79 having an air inlet 79i and an air outlet 79o, and a first heat exchanger 10a and a second heat exchanger 10b arranged side by side along the inner surface of the housing 79 and facing the air inlet 79i. The air conditioning unit 70 also includes a first blower 20a facing the first heat exchanger 10a and a second blower 20b facing the second heat exchanger 10b, arranged side by side inside the housing 79. The first blower 20a includes a centrifugal first fan 22a and a first casing 21a that houses the first fan 22a and forms an air passage for the first fan 22a, and that is arranged such that the air inlet surface Si, on which the air inlet opening 21i is formed, is along the first heat exchanger 10a. The second blower 20b has a centrifugal second fan 22b and a second casing 21b that houses the second fan 22b and forms an air path for the second fan 22b, and is arranged so that the suction surface Si on which the suction opening 21i is formed is aligned with the second heat exchanger 10b.

[0094] As described above, in the air conditioning unit 70 of the present disclosure, each blower 20 is a centrifugal blower and has a casing 21 that houses a fan 22. The suction surface Si of the casing 21 is arranged along the heat exchanger 10 that faces the blower 20. Therefore, the casing 21 that forms the air passage in each blower 20 makes the length of the air passage from the second heat exchanger 10b to the first fan 22a and the length of the air passage from the first heat exchanger 10a to the second fan 22b longer than in the past, thereby reducing the airflow that passes through such air passages. As a result, compared to the conventional configuration in which a plate-shaped component is provided, the air passages are separated by a structure that is functionally less wasteful, and the amount of air drawn by one blower 20 from the heat exchanger 10 facing the other blower 20 can be reduced.

[0095] The first fan 20a has a first fan motor 23a disposed inside the first casing 21a, and the second fan 20b has a second fan motor 23b disposed inside the second casing 21b (see FIG. 10). This allows the suction surface Si of each fan 20 to be located close to the opposing heat exchanger 10, thereby further enhancing the effect of reducing the amount of air drawn by one fan 20 from the opposing heat exchanger 10.

[0096] The housing 79 has an intake port 79i on its rear surface and an exhaust port 79o on its side surface (the left side surface in the example of FIG. 11 ) perpendicular to the rear surface. The first heat exchanger 10a and the second heat exchanger 10b are arranged side by side along the inner surface of the rear surface of the housing 79. The first blower 20a draws air only from the rear, with the rear wall portion 21r of the first casing 21a serving as the intake surface Si, and the motor body 23c of the first fan motor 23a is arranged on the front side inside the first casing 21a. The second blower 20b draws air only from the rear, with the rear wall portion 21r of the second casing 21b serving as the intake surface Si, and the motor body 23c of the second fan motor 23b is arranged on the front side inside the second casing 21b.

[0097] This makes it possible to suppress a decrease in the air volume caused by the fan motor 23 compared to a conventional configuration in which the motor body 23c of the fan motor 23 is arranged on the air intake side of the fan 22.

[0098] 16, the first casing 21a and the second casing 21b may be integrally formed, thereby reducing the number of parts.

[0099] The refrigeration cycle apparatus 100 according to the first embodiment is a refrigeration cycle apparatus having one or more refrigerant circuits (one refrigerant circuit C in the example of FIG. 1 ), and includes the above-described air conditioning unit 70. The one or more refrigerant circuits are configured so that the operating states of the first heat exchanger 10 a and the second heat exchanger 10 b can be switched independently.

[0100] As a result, for example, in a heating / defrosting operation in which one of the first heat exchanger 10a and the second heat exchanger 10b functions as an evaporator and the other functions as a condenser, when the blower 20 facing the heat exchanger 10 to be defrosted is stopped (see FIG. 2), efficient operation can be achieved and energy conservation can be achieved due to the effect of separating the air passages of the air conditioning unit 70. Also, for example, in a heating or cooling operation in which the required amount of heat exchange is small, refrigerant is caused to flow through only one of the first heat exchanger 10a and the second heat exchanger 10b, and only the corresponding blower 20 is operated, efficient operation can be achieved and energy conservation can be achieved due to the effect of separating the air passages of the air conditioning unit 70.

[0101] The refrigeration cycle apparatus 100 is also equipped with an indoor unit 60 connected to the air conditioning unit 70 via a connecting pipe RP and having an indoor heat exchanger 3. The one or more refrigerant circuits include one refrigerant circuit C in which a first heat exchanger 10a and a second heat exchanger 10b are connected in parallel to the indoor heat exchanger 3.

[0102] In this way, since the first heat exchanger 10a and the second heat exchanger 10b are connected in parallel in the refrigerant circuit C, the refrigeration cycle device 100 can operate in one of the first heat exchanger 10a and the second heat exchanger 10b and not the other (individual operation performed when the heat exchange volume requirement is small in cooling operation or normal heating operation), or operate in the opposite direction between the refrigerant flowing in the first heat exchanger 10a and the second heat exchanger 10b (heating / defrosting operation) by having one refrigerant circuit C.

[0103] Embodiment 2 Fig. 18 is a vertical cross-sectional view schematically showing an air conditioning unit 70 according to embodiment 2. The air conditioning unit 70 of embodiment 2 will be described with reference to Fig. 18. The air conditioning unit 70 of embodiment 2 differs from embodiment 1 in that it draws air from both the front and rear sides of the housing 79. Note that in embodiment 2, components having the same functions and actions as those in embodiment 1 are designated by the same reference numerals and their description will be omitted.

[0104] 18 , the air conditioning unit 70 of the second embodiment has intake ports 79i formed on the rear and front sides (i.e., the air blower chamber front panel 74) of a housing 79. An outdoor heat exchanger 1 consisting of a first heat exchanger 10a and a second heat exchanger 10b is provided at the intake ports 79i on the rear side and the front side of the housing 79, respectively. In the following, as in the first embodiment, it is defined that the second heat exchanger 10b is disposed below the first heat exchanger 10a in the outdoor heat exchanger 1.

[0105] The first fan 20a is disposed between the two front and rear first heat exchangers 10a, and the second fan 20b is disposed between the two front and rear second heat exchangers 10b. In the second embodiment, each fan 20 has an intake opening 21i formed in the rear wall 21r and the front wall 21f of the casing 21. That is, each fan 20 draws air from the rear and the front, using the rear wall 21r and the front wall 21f of the casing 21 as intake surfaces Si, respectively.

[0106] In each blower 20, the fan motor 23 (first fan motor 23a, second fan motor 23b) is a double-shaft fan motor in which both ends of a motor shaft 23d protrude from both sides of a motor body 23c. Impellers 22r, 22f are attached to these protruding portions of the motor shaft 23d. That is, in the second embodiment, the fan 22 (first fan 22a, second fan 22b) of each blower 20 is composed of two impellers 22r, 22f arranged on both sides of the motor body 23c. The motor body 23c is arranged in approximately the center of the casing 21 (first casing 21a, second casing 21b) in the depth direction (direction of arrow Y), with one impeller 22r arranged on the rear side and the other impeller 22f arranged on the front side. The fan 22 and the fan motor 23 are housed within the casing 21.

[0107] In the upper first fan 20a, the rear impeller 22r faces the suction opening 21i in the rear wall 21r of the first casing 21a and draws air from the rear first heat exchanger 10a through this suction opening 21i. In the first fan 20a, the front impeller 22f faces the suction opening 21i in the front wall 21f of the first casing 21a and draws air from the front first heat exchanger 10a through this suction opening 21i.

[0108] In the lower second fan 20b, the rear impeller 22r faces the suction opening 21i in the rear wall 21r of the second casing 21b and draws air from the rear second heat exchanger 10b through this suction opening 21i. In the second fan 20b, the front impeller 22f faces the suction opening 21i in the front wall 21f of the second casing 21b and draws air from the front second heat exchanger 10b through this suction opening 21i.

[0109] In the second embodiment, the casing 21 has a motor support portion 27 for fixing the motor main body 23c at an approximate center position in the depth direction (arrow Y direction) of the interior of the casing 21, i.e., at an approximate center position between the front wall portion 21f and the rear wall portion 21r. The motor support portion 27 has an outer periphery connected to the peripheral wall portion 21c of the casing 21, and the motor main body 23c is disposed and fixed in the central portion. That is, the motor support portion 27 supports the fan motor 23 inside the casing 21. The motor support portion 27 can be formed, for example, of a plate-like member. In each blower 20, the motor support portion 27 also functions to separate the air passage of the rear impeller 22r from the air passage of the front impeller 22f.

[0110] When the air conditioning unit 70 of embodiment 2 is applied to the refrigeration cycle apparatus 100 shown in Figure 1, for example, two first heat exchangers 10a of Figure 18 can be provided in series in the branch pipe 42a in which one first heat exchanger 10a is provided in the refrigerant circuit C of Figure 1, and two second heat exchangers 10b of Figure 18 can be provided in series in the branch pipe 42b in which one second heat exchanger 10b is provided in the refrigerant circuit C of Figure 1.

[0111] In the air conditioning unit 70 according to the second embodiment, as in the first embodiment, each blower 20 is a centrifugal blower and has a casing 21 that houses a fan 22, and the suction surface Si of the casing 21 is provided along the heat exchanger 10 that faces the blower 20. Therefore, the air conditioning unit 70 according to the second embodiment also achieves the same effects as the first embodiment. That is, compared to a conventional configuration in which a plate-shaped component is provided, the air passages are separated by a structure that is functionally less wasteful, and the amount of air drawn by one blower 20 from the heat exchanger 10 that faces the other blower 20 can be reduced.

[0112] In the second embodiment, the housing 79 has an intake port 79i on each of its rear and front sides, and an exhaust port 79o on a side surface perpendicular to the rear side (for example, the left side surface as shown in FIG. 11 ). The first heat exchanger 10a and the second heat exchanger 10b are provided in pairs on the rear side and the front side, respectively. The first blower 20a draws air from the rear and front sides, with the rear wall 21r and the front wall 21f of the first casing 21a serving as intake surfaces Si, respectively. The motor body 23c of the first fan motor 23a is disposed at a central position in the front-rear direction (direction of arrow Y) inside the first casing 21a. The second blower 20b draws in air from the rear and front, using the rear wall 21r and front wall 21f of the second casing 21b as suction surfaces Si, respectively, and the motor body 23c of the second fan motor 23b is arranged at the center position in the front-to-back direction (arrow Y direction) inside the second casing 21b.

[0113] This increases the heat exchange area in the air conditioning unit 70 compared to single-side suction, improving heat exchange performance. Therefore, the air speed, i.e., the fan rotation speed, can be reduced while ensuring the required heat exchange amount. Furthermore, reducing the fan rotation speed reduces the ventilation resistance of the heat exchanger 10, so a larger air volume can be obtained even with the same fan rotation speed.

[0114] Embodiment 3 Fig. 19 is a vertical cross-sectional view schematically showing an air conditioning unit 70 according to embodiment 3. The air conditioning unit 70 of embodiment 3 will be described with reference to Fig. 19. The air conditioning unit 70 of embodiment 3 differs from embodiment 1 in that it includes a partition wall 25 formed by a part of the casing 21. Note that in embodiment 3, components having the same functions and actions as those in embodiment 1 are designated by the same reference numerals, and description thereof will be omitted.

[0115] As shown in FIG. 19 , in the third embodiment, a partition wall 25 formed by a part of the casing 21 (first casing 21 a, second casing 21 b) extends toward the heat exchanger 10. The partition wall 25 closes the gap between the suction surface Si of the casing 21 and the heat exchanger 10 between the two air passages. Specifically, the partition wall 25 is configured such that a wall portion of the casing 21 of one of the fans 20 that faces the other fan 20 extends toward the heat exchanger 10 that faces the one fan 20. In the example of FIG. 19 , the partition wall 25 is a portion of the bottom surface of the first casing 21 a of the upper first fan 20 a that faces the second casing 21 b and extends horizontally rearward from the suction surface Si. The partition wall 25 has a substantially rectangular shape in a plan view. It is only necessary that the casing 21 of at least one of the two adjacent fans 20 has the partition wall 25 .

[0116] The configuration of the partition wall 25 is not limited to the above configuration. Fig. 20 is a vertical cross-sectional view schematically showing an air conditioning unit 70 according to a first modified example of Embodiment 3. In the example of Fig. 19 described above, the partition wall 25 is configured such that the wall portion of the casing 21 of one of the fans 20 that faces the other fan 20 extends horizontally toward the heat exchanger 10 that faces the one fan 20. However, in the first modified example shown in Fig. 20, the partition wall 25 of the casing 21 of one of the fans 20 is inclined toward the end of the opposing heat exchanger 10.

[0117] In the example of Fig. 20, the partition wall 25 is configured such that the bottom surface portion of the first casing 21a of the upper first blower 20a facing the second casing 21b is inclined from the suction surface Si toward the lower end 10ae of the downstream side surface 10d of the first heat exchanger 10a. In this manner, the partition wall 25 is arranged from the suction surface Si toward the heat exchanger 10 to connect the boundary between the two casings 21 and the boundary between the two heat exchangers 10, thereby separating the air passages while eliminating waste in the heat exchanger 10. In the example of Fig. 19, the lower end of the upper first heat exchanger 10a is located below the partition wall 25, resulting in waste at the lower end of the first heat exchanger 10a. In the example of FIG. 20, the air that has passed through the lower end of the first heat exchanger 10a is also guided by the partition wall 25 to the intake opening 21i of the first casing 21a, ensuring the ventilation volume of the first heat exchanger 10a.

[0118] FIG. 21 is a vertical cross-sectional view schematically illustrating an air conditioning unit 70 according to a second modification of the third embodiment. In the second modification illustrated in FIG. 21 , a partition wall 25 is applied to the integrated casing 121 illustrated in FIG. 16 . Specifically, the partition wall 25 is configured such that the boundary between the first casing 21 a and the second casing 21 b extends rearward from the suction surface Si toward the heat exchanger 10. While FIG. 21 illustrates a case in which the partition wall 25 extends horizontally, the partition wall 25 may be inclined as illustrated in FIG. 20 . Preferably, the partition wall 25 is provided so as to connect the boundary between the two casings 21 and the boundary between the two heat exchangers 10 from the suction surface Si toward the heat exchanger 10.

[0119] As described above, in the air conditioning unit 70 according to the third embodiment, as in the first embodiment, each blower 20 is a centrifugal blower and has a casing 21 that houses a fan 22, and the suction surface Si of the casing 21 is provided along the heat exchanger 10 that faces the blower 20. Therefore, the air conditioning unit 70 according to the third embodiment also achieves the same effects as the first embodiment. That is, compared to a conventional configuration in which a plate-shaped component is provided, the air passages are separated by a structure that is functionally less wasteful, and the amount of air drawn by one blower 20 from the heat exchanger 10 that faces the other blower 20 can be reduced.

[0120] In the third embodiment, at least one of the first casing 21 a and the second casing 21 b has a partition wall 25. The partition wall 25 extends from the suction surface Si to the suction port 79 i side (i.e., the heat exchanger 10 side) between the air passage of the first fan 22 a and the air passage of the second fan 22 b so as to close the gap between the suction surface Si and the first heat exchanger 10 a or the second heat exchanger 10 b facing the suction surface Si.

[0121] As a result, the partition 25 formed from a part of the casing 21 closes the gap between the suction surface Si of the blower 20 and the heat exchanger 10 between the air passages of the two fans 22, thereby reducing the amount of air drawn by one blower 20 from the heat exchanger 10 facing the other blower 20. That is, in operations in which the first heat exchanger 10a and the second heat exchanger 10b are in different operating states (for example, heating / defrosting operation, or individual operation in cooling operation or normal heating operation), efficient operation can be achieved with a rational structure that does not require major structural changes.

[0122] Embodiment 4. Figure 22 is a vertical cross-sectional view schematically showing an air conditioning unit 70 according to embodiment 4. The air conditioning unit 70 of embodiment 4 will be described with reference to Figure 22. Embodiment 4 differs from embodiment 3 in that the partition wall 25 of embodiment 3 is extended further rearward in the depth direction (direction of arrow Y). Note that in embodiment 4, components having the same functions and actions as those in embodiment 3 are denoted by the same reference numerals, and their description will be omitted.

[0123] 22, in the fourth embodiment, as in the third embodiment, a partition wall 25 is formed by a part of the casing 21. In the fourth embodiment, the partition wall 25 is further extended rearward and is also disposed below the first heat exchanger 10a, and this partition wall extension 26 is configured to receive water from the first heat exchanger 10a above.

[0124] The partition wall extension 26 has, for example, a generally L-shaped end bent upward. A drain hole (not shown) is provided in the partition wall extension 26, and water received by the partition wall extension 26 from the first heat exchanger 10a is discharged to the outside of the housing 79 through the drain hole.

[0125] In this way, in embodiment 4, a portion of the casing 21 blocks the gap between the suction surface Si of the blower 20 and the heat exchanger 10 in the depth direction (arrow Y direction) at the boundary between the two blowers 20, thereby separating the air passages, and also functions as a drain pan for the upper first heat exchanger 10a.

[0126] In the air conditioning unit 70 according to the fourth embodiment, as in the first embodiment, each blower 20 is a centrifugal blower and has a casing 21 that houses a fan 22, and the suction surface Si of the casing 21 is provided along the heat exchanger 10 that faces the blower 20. Therefore, the air conditioning unit 70 according to the fourth embodiment also achieves the same effects as the first embodiment. That is, compared to a conventional configuration in which a plate-shaped component is provided, the air passages are separated by a structure that is functionally less wasteful, and the amount of air drawn by one blower 20 from the heat exchanger 10 that faces the other blower 20 can be reduced.

[0127] In the air conditioning unit 70 according to the fourth embodiment, the first heat exchanger 10a and the second heat exchanger 10b are disposed above and below each other and are separated from each other. At least one of the first casing 21a and the second casing 21b has a partition wall 25, and the partition wall 25 has a partition wall extension 26 disposed between the first heat exchanger 10a and the second heat exchanger 10b. The partition wall extension 26 receives water from the upper first heat exchanger 10a.

[0128] In this way, by disposing the partition wall extension 26, which is formed from a part of the casing 21, between the first heat exchanger 10a and the second heat exchanger 10b, recovery of water from the upper first heat exchanger 10a can be realized with a more rational structure that does not involve major structural changes. For example, when the upper first heat exchanger 10a is the defrost target during heating / defrosting operation, the part of the casing 21 can prevent water from the upper first heat exchanger 10a from dripping onto the lower second heat exchanger 10b and forming frost.

[0129] Fifth Embodiment Fig. 23 is a circuit diagram showing a refrigeration cycle apparatus 200 according to a fifth embodiment. The refrigeration cycle apparatus 200 according to the fifth embodiment will be described below based on Fig. 23 and with reference to Figs. 10 and 11. In the fifth embodiment, as in the first embodiment, the refrigeration cycle apparatus 200 has a circuit configuration in which the operating states of the first heat exchanger 10a and the second heat exchanger 10b can be independently switched. Accordingly, the airflow (operation and stoppage, or airflow volume) to the first heat exchanger 10a and the second heat exchanger 10b is individually controlled.

[0130] In the fifth embodiment, the refrigeration cycle apparatus 200 has two completely independent refrigeration cycles (a first refrigerant circuit Ca and a second refrigerant circuit Cb). The configurations and arrangements of the housing 79, the outdoor heat exchanger 1 (the first heat exchanger 10a and the second heat exchanger 10b), and the outdoor blower 2 (the first blower 20a and the second blower 20b) in the air conditioning unit 270 are the same as those in the air conditioning unit 70 in the first embodiment. Note that the configurations and arrangements in the air conditioning unit 270 may be the same as those in the second, third, or fourth embodiment. In the fifth embodiment, the first heat exchanger 10a and the second heat exchanger 10b constituting the outdoor heat exchanger 1 are heat exchangers of mutually independent refrigerant circuits (the first refrigerant circuit Ca and the second refrigerant circuit Cb).

[0131] The refrigeration cycle apparatus 200 has one air conditioning unit 270 and two indoor units 260 (a first indoor unit 260a and a second indoor unit 260b). The air conditioning unit 270 is connected to the first indoor unit 260a by a connecting pipe RPa to form a first refrigerant circuit Ca, and is connected to the second indoor unit 260b by a connecting pipe RPb to form a second refrigerant circuit Cb.

[0132] Here, the refrigeration cycle apparatus 200 is defined as having two refrigerant circuits (a first refrigerant circuit Ca and a second refrigerant circuit Cb), and accordingly, the outdoor heat exchanger 1 is defined as being composed of two heat exchangers 10 (a first heat exchanger 10a and a second heat exchanger 10b), the air conditioning unit 70 is equipped with two fans 20 (a first fan 20a and a second fan 20b), and two indoor units 260 are connected to the air conditioning unit 70. Note that the number of refrigerant circuits constituting the refrigeration cycle apparatus 200, the number of heat exchangers 10 constituting the outdoor heat exchanger 1, the number of fans 20 mounted in the air conditioning unit 270, and the number of indoor units 260 connected to the air conditioning unit 270 may each be three or more.

[0133] The compressor 5a, the flow switching device 6a, the indoor heat exchanger 3a, the expansion device 8a, the first heat exchanger 10a, and the accumulator 4a are connected by a pipe 241a to form a first refrigerant circuit Ca through which the refrigerant circulates. The compressor 5b, the flow switching device 6b, the indoor heat exchanger 3b, the expansion device 8b, the second heat exchanger 10b, and the accumulator 4b are connected by a pipe 241b to form a second refrigerant circuit Cb through which the refrigerant circulates.

[0134] Two compressors 5a and 5b, two flow switching devices 6a and 6b, an outdoor heat exchanger 1 (a first heat exchanger 10a and a second heat exchanger 10b), two accumulators 4a and 4b, two expansion devices 8a and 8b, and an outdoor blower 2 (a first blower 20a and a second blower 20b) are arranged in one housing 79 (see FIG. 10) of the air conditioning unit 270. Of these devices, the outdoor heat exchanger 1 and the outdoor blower 2 are arranged in an air blower chamber F (see FIG. 11), and the remaining devices are arranged in a machine chamber M (see FIG. 11).

[0135] The first indoor unit 260a includes an indoor heat exchanger 3a of a first refrigerant circuit Ca and an indoor fan 11a that sends indoor air to the indoor heat exchanger 3a. The second indoor unit 260b includes an indoor heat exchanger 3b of a second refrigerant circuit Cb and an indoor fan 11b that sends indoor air to the indoor heat exchanger 3b.

[0136] The control device 15 controls the two refrigeration cycles individually. The control device 15 controls the frequencies of the compressors 5a and 5b, the switching of the flow path switching devices 6a and 6b, the opening degrees of the expansion devices 8a and 8b, the fan rotation speeds of the blowers 20 of the outdoor blower 2, and the fan rotation speeds of the indoor blowers 11a and 11b.

[0137] However, in a refrigeration cycle device having only one refrigeration cycle, when the load on the indoor side differs, or when only some of the indoor units are operated depending on whether or not a room is present, it is difficult to maintain high efficiency under all operating conditions according to the load, and it may be necessary to design the device to suit a certain range of frequencies.

[0138] However, if a configuration is adopted in which a plurality of completely independent refrigeration cycles are provided, as in the refrigeration cycle apparatus 200 of the present embodiment 5, the range of change in the operating conditions (frequency) of each of the compressors 5a, 5b can be reduced by changing the number of compressors to be started, and high efficiency can be maintained. Furthermore, even if one of the compressors 5a fails, the remaining compressor 5b can continue to operate, and the extent to which operation is affected can be minimized.

[0139] In the air conditioning unit 270 according to the fifth embodiment, as in the first embodiment, each blower 20 is a centrifugal blower and has a casing 21 that houses a fan 22, and the suction surface Si of the casing 21 is provided along the heat exchanger 10 that faces the blower 20 (see FIG. 10 ). Therefore, the air conditioning unit 270 according to the fifth embodiment also achieves the same effects as the first embodiment. That is, compared to a conventional configuration in which a plate-shaped component is provided, the air passages are separated by a structure that is functionally less wasteful, and the amount of air drawn by one blower 20 from the heat exchanger 10 that faces the other blower 20 can be reduced.

[0140] Furthermore, a refrigeration cycle apparatus 200 according to a fifth embodiment is a refrigeration cycle apparatus having one or more refrigerant circuits, and includes the above-described air conditioning unit 270. The one or more refrigerant circuits are configured so that the first heat exchanger 10a and the second heat exchanger 10b can independently switch their operating states. Specifically, the one or more refrigerant circuits include a first refrigerant circuit Ca having the first heat exchanger 10a, and a second refrigerant circuit Cb provided independently of the first refrigerant circuit Ca and having the second heat exchanger 10b.

[0141] As described above, the refrigeration cycle apparatus 200 of the fifth embodiment includes the air conditioning unit 270, and the first heat exchanger 10a and the second heat exchanger 10b are provided in separate refrigerant circuits (the first refrigerant circuit Ca and the second refrigerant circuit Cb). Therefore, in the refrigeration cycle apparatus 200 of the fifth embodiment, the range of change in the operating conditions (frequency) of the compressors 5a and 5b can be made smaller than when a common compressor 5 is used, and more efficient operation can be achieved.

[0142] REFERENCE SIGNS LIST 1 outdoor heat exchanger, 2 outdoor fan, 3 indoor heat exchanger, 3a indoor heat exchanger, 3b indoor heat exchanger, 4 accumulator, 4a accumulator, 4b accumulator, 5 compressor, 5a compressor, 5b compressor, 6 flow path switching device, 6a flow path switching device, 6b flow path switching device, 8a throttle device, 8b throttle device, 9 bypass circuit, 9a bypass circuit, 9b bypass circuit, 10 heat exchanger, 10a first heat exchanger, 10ae lower end, 10b second heat exchanger, 10d downstream side, 11 indoor fan, 11a indoor fan, 11b indoor fan, 12a flow rate adjustment device, 12b flow rate adjustment device, 13a bypass flow rate adjustment device, 13b bypass flow rate adjustment device, 15 control device, 20 fan, 20a First blower, 20b Second blower, 21 Casing, 21a First casing, 21b Second casing, 21c Peripheral wall portion, 21f Front wall portion, 21i Intake opening, 21o Outlet opening, 21r Rear wall portion, 22 Fan, 22a First fan, 22b Second fan, 22f Impeller, 22r Impeller, 23 Fan motor, 23a First fan motor, 23b Second fan motor, 23c Motor body, 23d Motor shaft, 25 Partition wall, 26 Partition wall extension portion, 27 Motor support portion, 40 Main circuit, 41 Main pipe, 42 Branch pipe, 42a Branch pipe, 42b Branch pipe, 45 Heat transfer tube, 45h Hole, 45p Protrusion portion, 46 Fin, 50 First header, 51 Second header, 52 First inlet / outlet piping, 53 Second inlet / outlet piping, 60 Indoor unit, 70 Air conditioning unit, 71 Top plate, 72 Bottom plate, 73 Machine room panel, 74 Front panel of blower room, 75 Partition plate, 75h Wiring hole, 79 Housing, 79i Intake port, 79o Outlet port, 81a Fixing device, 81b Fixing device, 91 Bypass piping, 91a Bypass piping, 91b Bypass piping, 100 Refrigeration cycle device, 121 Casing, 200 Refrigeration cycle device, 241a Piping, 241b Piping, 260 Indoor unit, 260a First indoor unit, 260b Second indoor unit, 270 Air conditioning unit, C Refrigerant circuit, Ca First refrigerant circuit, Cb Second refrigerant circuit, F Blower room, G Gap, L Distance, M Machine room, P Wiring, Pa Wiring, Pb Wiring, RP connecting pipe, RPa connecting pipe, RPb connecting pipe, Si suction surface, Wf blower chamber wall surface.

Claims

1. An air conditioning unit, comprising: a housing provided with a suction port and a blowout port; a first heat exchanger and a second heat exchanger arranged side by side along the inner surface of the housing, each facing the suction port; a first blower and a second blower arranged side by side inside the housing, the first blower facing the first heat exchanger and the second blower facing the second heat exchanger; the first blower having a centrifugal first fan and a first casing that houses the first fan inside and forms an air passage of the first fan, and the suction surface with a suction opening formed thereon is arranged along the first heat exchanger; the second blower having a centrifugal second fan and a second casing that houses the second fan inside and forms an air passage of the second fan, and the suction surface with a suction opening formed thereon is arranged along the second heat exchanger.

2. The air conditioning unit according to claim 1, wherein the first blower has a first fan motor arranged inside the first casing, and the second blower has a second fan motor arranged inside the second casing.

3. The air conditioning unit according to claim 2, wherein the housing is provided with the suction port on the rear surface and the blowout port on the side surface orthogonal to the rear surface; the first heat exchanger and the second heat exchanger are arranged side by side along the inner surface of the rear surface; the first blower sucks air only from the rear with the rear wall portion of the first casing as the suction surface, and the motor body of the first fan motor is arranged on the front side inside the first casing; the second blower sucks air only from the rear with the rear wall portion of the second casing as the suction surface, and the motor body of the second fan motor is arranged on the front side inside the second casing.

4. The housing is provided with the suction ports on the back surface and the front surface respectively, and the air outlet is provided on the side surface orthogonal to the back surface. One set of the first heat exchanger and the second heat exchanger is provided on each of the back side and the front side. The first blower sucks air from the rear and the front using the rear wall portion and the front wall portion of the first casing as the suction surfaces respectively, and the motor body of the first fan motor is arranged at the central position in the front-rear direction inside the first casing. The second blower sucks air from the rear and the front using the rear wall portion and the front wall portion of the second casing as the suction surfaces respectively, and the motor body of the second fan motor is arranged at the central position in the front-rear direction inside the second casing. The air-conditioning unit according to claim 2.

5. The first casing and the second casing are integrally provided. The air-conditioning unit according to any one of claims 1 to 4.

6. At least one of the first casing and the second casing has a partition wall extending from the suction surface toward the suction port side so as to block the gap between the suction surface and the first heat exchanger or the second heat exchanger facing the suction surface between the air passage of the first fan and the air passage of the second fan. The air-conditioning unit according to any one of claims 1 to 5.

7. The first heat exchanger and the second heat exchanger are arranged vertically and are divided from each other. The partition wall is arranged between the first heat exchanger and the second heat exchanger and has a partition wall extension portion for receiving water from the upper first heat exchanger. The air-conditioning unit according to claim 6.

8. A refrigeration cycle device having one or more refrigerant circuits, comprising the air-conditioning unit according to any one of claims 1 to 7, wherein the one or more refrigerant circuits are configured such that the first heat exchanger and the second heat exchanger can be independently switched in the operating state. Refrigeration cycle device.

9. An indoor unit having an indoor heat exchanger, connected to the air-conditioning unit via a connecting pipe, wherein the one or more refrigerant circuits include one refrigerant circuit in which the first heat exchanger and the second heat exchanger are connected in parallel to the indoor heat exchanger. The refrigeration cycle device according to claim 8.

10. The refrigeration cycle device according to claim 8, wherein the one or more refrigerant circuits include a first refrigerant circuit having the first heat exchanger and a second refrigerant circuit provided independently of the first refrigerant circuit and having the second heat exchanger.

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