Refrigeration cycle device

The refrigeration cycle device addresses refrigerant flow foldback issues by maintaining consistent flow directions and optimizing port arrangements, resulting in reduced pressure loss and improved efficiency.

WO2026133736A1PCT designated stage Publication Date: 2026-06-25DAIKIN INDUSTRIES LTD

Patent Information

Authority / Receiving Office
WO · WO
Patent Type
Applications
Current Assignee / Owner
DAIKIN INDUSTRIES LTD
Filing Date
2025-10-27
Publication Date
2026-06-25

AI Technical Summary

Technical Problem

Conventional refrigeration cycle devices experience a decrease in Cv value and pressure loss due to refrigerant flow foldback within the flow path switching valve, leading to inefficiencies.

Method used

A refrigeration cycle device with a flow path switching valve that maintains consistent refrigerant flow direction through the valve body, utilizing internal and external flow paths to minimize foldback and pressure loss, and optimizes port arrangement to ensure smooth refrigerant flow without detours.

Benefits of technology

The solution reduces pressure loss and enhances efficiency by preventing refrigerant foldback, allowing for a compact and efficient refrigeration cycle operation.

✦ Generated by Eureka AI based on patent content.

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Patent Text Reader

Abstract

Provided is an efficient refrigeration cycle device capable of reducing pressure loss in a flow path switching valve. An air conditioner (1) is equipped with a flow path switching valve (100). This flow path switching valve includes: a main body casing (120) in which a first space V1 is formed and which has an outer surface (124) provided with ports (130a-130d) ; and a valve body disposed in the first space and forming a first flow path through which a refrigerant flows. The state of the valve body is switched between a first state in which a first port and a second port are connected to each other by the first flow path and a second state in which the first port and a third port are connected to each other by the first flow path. Refrigerants always flow in the same direction in the second port and the third port. The main body casing comprises a first end (125a) and a second end (125b). The second and third ports are disposed at the first end (125a). The first port is arranged at the second end (125b).
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Description

Refrigeration cycle device

[0001] It relates to a refrigeration cycle device.

[0002] A flow path switching valve may be provided in the refrigeration cycle device for the purpose of controlling the refrigerant flowing through the heat exchanger (for example, Patent Document 1 (Japanese Patent Application Laid-Open No. 2010-112517)).

[0003] In such a flow path switching valve, conventionally, the refrigerant flows through the flow path switching valve in a manner as shown in FIG. 10, for example. As can be seen from FIG. 10, in the conventional flow path switching valve, depending on the connection state of the flow path (in the second switching state in FIG. 10), a foldback of the refrigerant flow occurs in the flow path switching valve. When such a foldback of the refrigerant flow occurs in the flow path switching valve, the Cv value of the flow path switching valve decreases, and a relatively large pressure loss may occur in the flow path switching valve.

[0004] The refrigeration cycle device of the first aspect includes a refrigerant circuit. In the refrigerant circuit, a compressor, a first heat exchanger, an expansion valve, and a second heat exchanger are connected by refrigerant pipes. The refrigeration cycle device includes a flow path switching valve and a control device. The flow path switching valve has a main body casing, a valve body, and a drive unit. A first space is formed inside the main body casing. On the outer surface of the main body casing, a first port, a second port, a third port, and a fourth port, which are inlets and outlets of the refrigerant, are provided. The valve body is disposed inside the first space. The valve body forms a first flow path through which the refrigerant flows. The drive unit drives the valve body. The control device controls the drive unit. The control device controls the drive unit to switch the state of the valve body between a first state and a second state. When the valve body is in the first state, the first port and the second port are connected by the first flow path. When the valve body is in the second state, the first port and the third port are connected by the first flow path. In the second port, the refrigerant always flows in the same first direction. In the third port, the refrigerant always flows in the same second direction. The main body casing has a first end and a second end. The second port and the third port are disposed at the first end of the main body casing, and the first port is disposed at the second end of the main body casing.

[0005] In the refrigeration cycle device of the first perspective, even when the state of the valve body is switched between the first and second states, the refrigerant flowing into or out of the first port always flows in the same direction. Therefore, in the refrigeration cycle device of the first perspective, the refrigerant flowing into or out of the first port does not fold back within the valve body, and the decrease in Cv value (reduction of pressure loss) that occurs due to the refrigerant folding back within the valve body is suppressed, thereby realizing an efficient refrigeration cycle device.

[0006] A refrigeration cycle device according to the second aspect is a refrigeration cycle device according to the first aspect, wherein the first flow path includes an internal flow path formed inside a valve body. The valve body further forms a second flow path in the first space that is different from the first flow path. The internal flow path connects the first port and the second port in the first state, and connects the first port and the third port in the second state. The second flow path connects the third port and the fourth port when the valve body is in the first state, and connects the second port and the fourth port when the valve body is in the second state.

[0007] In the refrigeration cycle device from the second perspective, by utilizing a second flow path outside the valve body as a refrigerant flow path in addition to the internal flow path formed inside the valve body, the valve body can be miniaturized, and a compact flow path switching valve can be realized.

[0008] The refrigeration cycle device of the third perspective is the refrigeration cycle device of the second perspective, in which, regardless of whether the valve body is in the first or second state, when viewing the main casing from the first end to the second end of the main casing, the flow of refrigerant through the internal passage and the flow of refrigerant through the second passage do not intersect.

[0009] In the third-party refrigeration cycle system, arranging the first to fourth ports to satisfy the above conditions allows the refrigerant to flow smoothly (without taking detours that bypass the valve body), thereby reducing pressure loss within the flow path switching valve.

[0010] The refrigeration cycle device of the fourth aspect is a refrigeration cycle device of any of the first, second, or third aspects, wherein the main casing is provided with a first internal port communicating with a first port, a second internal port communicating with a second port, and a third internal port communicating with a third port on the wall surface forming a first space. When viewing the first internal port, the second internal port, and the third internal port from a direction perpendicular to the direction in which the second and third internal ports are arranged side by side, and perpendicular to the third direction in which the first and second ends are aligned, at least a part of the first internal port is positioned between a virtual line extending in the third direction through the center of the opening of the second internal port and a virtual line extending in the third direction through the center of the opening of the third internal port.

[0011] In the refrigeration cycle device of the fourth perspective, by arranging the first to third ports in a way that satisfies the above conditions, the refrigerant can flow smoothly (without taking a roundabout route) through the internal flow path in the first and second states, thereby reducing pressure loss within the flow path switching valve.

[0012] The refrigeration cycle device according to the fifth aspect is the refrigeration cycle device according to the fourth aspect, further comprising a sealing member. The sealing member is provided so as to surround the opening of the first internal port, the opening of the second internal port, and the opening of the third internal port. When the first internal port, the second internal port, and the third internal port are connected to the internal flow path, the sealing member seals the space between the opening of the internal port connected to the internal flow path and the valve body.

[0013] In the fifth aspect of the refrigeration cycle system, when each internal port is connected to the internal flow path of the valve body, it is possible to suppress situations in which refrigerant flows out from the internal port connected by the internal flow path into the first space around the valve body, or in from the first space around the valve body into the internal port connected by the internal flow path, thereby realizing an efficient refrigeration cycle system.

[0014] The refrigeration cycle device of the sixth aspect is a refrigeration cycle device of any of the first or fifth aspects, wherein the fourth port is located at the second end of the main casing.

[0015] In the sixth-perspective refrigeration cycle device, the refrigerant flowing into or out of the fourth port always flows in the same direction between the first and second ends. Therefore, in the sixth-perspective refrigeration cycle device, the refrigerant flowing into or out of the fourth port does not fold back within the valve body, suppressing the decrease in Cv value (reducing pressure loss) that would occur due to the refrigerant folding back within the valve body, thereby realizing an efficient refrigeration cycle device.

[0016] The refrigeration cycle device of the seventh aspect is the refrigeration cycle device of the sixth aspect, wherein the second port and the third port are arranged side by side in the fourth direction at the first end of the main casing, and the first port and the fourth port are arranged side by side in a direction intersecting the fourth direction at the second end of the main casing.

[0017] In the refrigeration cycle device of the seventh perspective, by arranging the first to fourth ports to satisfy the above conditions, the refrigerant can flow smoothly (without taking a roundabout route) through the internal flow path in the first and second states, and pressure loss within the flow path switching valve can be reduced.

[0018] The refrigeration cycle device of the eighth perspective is the refrigeration cycle device of the first and seventh perspectives, wherein the drive unit rotates the valve body around the rotation axis to switch the state of the valve body between a first state and a second state.

[0019] In the refrigeration cycle system described in the eighth perspective, different flow path connection states can be achieved using flow path switching valves with a relatively simple structure.

[0020] The refrigeration cycle device of the ninth aspect is the refrigeration cycle device of the eighth aspect from the first aspect, wherein the inner diameter of the fourth port is smaller than the inner diameter of the first port.

[0021] In the refrigeration cycle device of the ninth perspective, the inner diameter of the fourth port is smaller than that of the first port, which increases the flexibility of the placement of the fourth port. Furthermore, by reducing the diameter of the refrigerant piping that communicates with the fourth port to match the inner diameter of the fourth port, the flexibility of the piping route of the refrigerant piping connected to the flow path switching valve can be increased.

[0022] The refrigeration cycle device of the tenth aspect is the refrigeration cycle device of the first aspect and the ninth aspect, wherein the second port and the third port are arranged on a plane provided at the first end of the main casing.

[0023] In the refrigeration cycle device of the tenth perspective, the routing of piping connected to the second and third ports can be simplified by arranging the second and third ports on the same plane.

[0024] The refrigeration cycle device of the 11th aspect is the refrigeration cycle device of the 10th aspect from the 1st aspect, and the refrigeration cycle device is an air conditioner. The second port communicates with the first connection part, which is the inlet for the refrigerant of the first heat exchanger, where heat exchange takes place between the refrigerant flowing inside and the air in the space to be air-conditioned. The third port communicates with the second connection part, which is the outlet for the refrigerant of the first heat exchanger. The first heat exchanger and the flow path switching valve are housed inside the casing.

[0025] In the refrigeration cycle device of the 11th perspective, since the second and third ports are located at the same end (first end) of the main casing, the routing of the piping connecting the first heat exchanger and the flow path switching valve can be simplified, and the size of the housing that accommodates the first heat exchanger and the flow path switching valve can also be suppressed.

[0026] The refrigeration cycle device of the 12th aspect is the refrigeration cycle device of the 11th aspect from the first aspect, wherein the valve body is ball-shaped, with at least a part of its outer surface being spherical.

[0027] This is a schematic diagram of an air conditioner according to one embodiment. This is a schematic external view of the flow path switching valve of the air conditioner in Figure 1. This is a side view of 1 showing the inside of the flow path switching valve. This is a side view of 1 showing the inside of the flow path switching valve from a different direction than that in Figure 3. This is a view of the valve body of the flow path switching valve from the opposite side of the planar portion of the flow path switching valve. This is a view of the valve body of Figure 5A from a different direction than that in Figure 5A. This is a schematic diagram showing the inside of the flow path switching valve when the valve body is in the first state. This is a schematic diagram showing the inside of the flow path switching valve when the valve body is in the second state. This is a diagram showing the flow of refrigerant in the refrigerant circuit during cooling operation. This is a diagram showing the flow of refrigerant in the refrigerant circuit during heating operation. This is an example of a port arrangement in which the flow of refrigerant flowing through the internal flow path and the flow of refrigerant flowing through the second flow path do not intersect when the valve body is in either the first or second state, and the flow of refrigerant in the first state is shown by the dashed-dotted line and the dashed-dotted line. This is an example of a port configuration in which the flow of refrigerant through the internal channel and the flow of refrigerant through the second channel do not intersect, regardless of whether the valve body is in the first or second state, and the flow of refrigerant in the second state is shown by a double-dotted line and a single-dotted line. Depending on the state of the valve body, this is an example of a port configuration in which the flow of refrigerant through the internal channel and the flow of refrigerant through the second channel intersect, and the flow of refrigerant in the first state is shown by a double-dotted line and a solid line. Depending on the state of the valve body, this is an example of a port configuration in which the flow of refrigerant through the internal channel and the flow of refrigerant through the second channel intersect, and the flow of refrigerant in the second state is shown by a double-dotted line and a solid line. This is a diagram for explaining the flow of refrigerant inside a conventional flow switching valve, and depicts a first connection state in which the refrigerant flows across the flow switching valve and a second connection state in which the refrigerant folds back and flows inside the flow switching valve.

[0028] A refrigeration cycle device according to one embodiment will be described with reference to the drawings.

[0029] (1) Overview The overview of the air conditioner 1, which is an embodiment of a refrigeration cycle device, will be explained with reference to Figure 1. Note that the type of refrigeration cycle device is not limited to an air conditioner, and other types of devices that use a vapor compression refrigeration cycle to cool or heat the target may also be used.

[0030] The air conditioner 1 provides cooling and heating to the interior of a house or building (the space to be air-conditioned). The air conditioner 1 mainly consists of a heat source unit 2, a utilization unit 4, and a control unit 90 (see Figure 1). In the example in Figure 1, there is one utilization unit 4, but there may be multiple utilization units 4.

[0031] As shown in Figure 1, the heat source unit 2 and the utilization unit 4 are connected by connecting pipes 6 and 8. In the air conditioner 1, the connection of the heat source unit 2 and the utilization unit 4 by connecting pipes 6 and 8 forms a refrigerant circuit 50. The refrigerant circuit 50 includes a compressor 10, a flow path switching mechanism 12, a heat source heat exchanger 14, an expansion valve 16, an accumulator 18, a liquid shut-off valve 17a, a gas shut-off valve 17b, a utilization heat exchanger 22, and a flow path switching valve 100. The flow path switching valve 100 is a device for directing the refrigerant to flow in the same direction to the utilization heat exchanger 22 during cooling and heating operations.

[0032] The refrigerant circuit 50 is filled with a refrigerant that has thermal glide, such as R454C, although this is not limited to R454C. However, the refrigerant filled in the refrigerant circuit 50 is not limited to R454C. Also, the refrigerant filled in the refrigerant circuit 50 is not limited to a refrigerant that has thermal glide. The refrigerant filled in the refrigerant circuit 50 can be selected as appropriate.

[0033] (2) Detailed configuration (2-1) Heat source unit The heat source unit 2 is installed on the rooftop or in the machine room of the building where the air conditioner 1 is installed.

[0034] As shown in Figure 1, the heat source unit 2 mainly comprises a compressor 10, a flow path switching mechanism 12, a heat source heat exchanger 14, an expansion valve 16, an accumulator 18, a liquid shut-off valve 17a, a gas shut-off valve 17b, and a heat source fan 15. The various components 10, 12, 14, 16, 18, 17a, 17b, and 15 of the heat source unit 2 are housed within the casing 2a.

[0035] The suction pipe 19a connects the flow path switching mechanism 12 to the suction side of the compressor 10. An accumulator 18 is provided in the suction pipe 19a. The discharge pipe 19b connects the discharge side of the compressor 10 to the flow path switching mechanism 12. The first gas pipe 19c connects the flow path switching mechanism 12 to the gas side end of the heat source heat exchanger 14. The liquid pipe 19d connects the liquid side end of the heat source heat exchanger 14 to the liquid connecting pipe 6. An expansion valve 16 is provided in the liquid pipe 19d. A liquid shut-off valve 17a is provided at the connection between the liquid pipe 19d and the liquid connecting pipe 6. The second gas pipe 19e connects the flow path switching mechanism 12 to the gas connecting pipe 8. A gas shut-off valve 17b is provided at the connection between the second gas pipe 19e and the gas connecting pipe 8. The liquid shut-off valve 17a and the gas shut-off valve 17b are manually operated valves and are open when the air conditioner 1 is in operation.

[0036] The compressor 10 draws in low-pressure refrigerant from the refrigeration cycle through the suction pipe 19a, compresses the refrigerant using a compression mechanism (not shown), and discharges the compressed high-pressure refrigerant from the refrigeration cycle through the discharge pipe 19b. The compressor 10 is not limited to a specific type, but for example, it is a positive displacement compressor such as a rotary or scroll type. The compression mechanism of the compressor 10 is driven by a motor (not shown). The compressor 10 is an inverter compressor. However, the compressor 10 may also be a constant-speed compressor.

[0037] The flow path switching mechanism 12 switches the flow path of the refrigerant between a first circuit state and a second circuit state. In other words, the flow path switching mechanism 12 switches the destination of the refrigerant discharged from the compressor between the heat source heat exchanger 14 and the utilization heat exchanger 22. In the first circuit state, as shown by the solid line in the flow path switching mechanism 12 in Figure 1, the suction pipe 19a is connected to the second gas pipe 19e and the discharge pipe 19b is connected to the first gas pipe 19c. In the second circuit state, as shown by the dashed line in the flow path switching mechanism 12 in Figure 1, the suction pipe 19a is connected to the first gas pipe 19c and the discharge pipe 19b is connected to the second gas pipe 19e.

[0038] The flow path switching mechanism 12 is not limited to a specific type, but for example, it may be a four-way switching valve (solenoid operated valve, solenoid pilot switching valve, etc.). However, it is not limited to this, and the flow path switching mechanism 12 may also be a mechanism that has multiple solenoid valves connected to the piping and switches the flow path of the refrigerant between a first circuit state and a second circuit state by operating the multiple solenoid valves.

[0039] During cooling operation, the flow path switching mechanism 12 sets the refrigerant flow path to the first circuit state. At this time, the refrigerant discharged from the compressor 10 flows through the refrigerant circuit 50 in the following order: heat source heat exchanger 14, expansion valve 16, flow path switching valve 100, utilization heat exchanger 22, flow path switching valve 100, and returns to the compressor 10. In the first circuit state, the heat source heat exchanger 14 functions as a heat radiator (condenser), and the utilization heat exchanger 22 functions as a heat absorber (evaporator).

[0040] During heating operation, the flow path switching mechanism 12 sets the refrigerant flow path to the second circuit state. At this time, the refrigerant discharged from the compressor 10 flows through the refrigerant circuit 50 in the following order: flow path switching valve 100, utilization heat exchanger 22, flow path switching valve 100, expansion valve 16, heat source heat exchanger 14, and returns to the compressor 10. In the second circuit state, the heat source heat exchanger 14 functions as a heat absorber (evaporator), and the utilization heat exchanger 22 functions as a heat radiator (condenser).

[0041] The heat source heat exchanger 14 performs heat exchange between the refrigerant flowing inside the heat source heat exchanger 14 and the air surrounding the heat source unit 2. The heat source heat exchanger 14 is, for example, a fin-and-tube type heat exchanger having a plurality of heat transfer fins and a plurality of heat transfer tubes. Note that the substance with which the refrigerant exchanges heat in the heat source heat exchanger 14 is not limited to air, but may be a liquid such as water. If the substance with which the refrigerant exchanges heat is a liquid, then a heat exchanger suitable for heat exchange between the liquid and the refrigerant should be selected for the heat source heat exchanger 14.

[0042] The expansion valve 16 is a mechanism for adjusting the pressure and flow rate of the refrigerant flowing through the liquid pipe 19d. The expansion valve 16 is installed in the liquid pipe 19d. The expansion valve 16 is, for example, an electrically operated valve (electronic expansion valve) with adjustable opening. However, the type of expansion valve 16 is not limited to an electrically operated valve, and may be a temperature-controlled automatic expansion valve, etc.

[0043] The accumulator 18 is a container provided in the suction pipe 19a and having a gas-liquid separation function for separating the flowing refrigerant into a gaseous refrigerant and a liquid refrigerant. The refrigerant flowing into the accumulator 18 is separated into a gaseous refrigerant and a liquid refrigerant, and the gaseous refrigerant collected in the upper space flows into the compressor 10.

[0044] The heat source fan 15 supplies air serving as a heat source around the heat source unit 2 to the heat source heat exchanger 14. The heat source fan 15 is not limited to the type of fan, but is, for example, an axial flow fan such as a propeller fan. The heat source fan 15 is driven by a motor (not shown).

[0045] The heat source unit 2 further has a heat source control unit (not shown). The heat source control unit has a control arithmetic device and a storage device. The control arithmetic device is a processor such as a CPU and a GPU. The storage device is a storage medium such as a RAM, a ROM, and a flash memory. The control arithmetic device reads out a program stored in the storage device, performs a predetermined arithmetic process according to the program, and cooperates with a utilization control unit (not shown) of the utilization unit 4 to control the operations of various devices of the air conditioner 1 as the control unit 90. The function of the control unit 90 will be described later.

[0046] (2-2) Utilization unit The utilization unit 4 is installed in an air-conditioning target space that is the object of air conditioning. The utilization unit 4 is, for example, a ceiling-embedded type, a ceiling-suspended type, a wall-mounted type, a floor-standing type unit, or the like.

[0047] As shown in FIG. 1, the utilization unit 4 mainly includes a utilization heat exchanger 22, a utilization fan 24, and a flow path switching valve 100. The utilization heat exchanger 22, the utilization fan 24, and the flow path switching valve 100 are housed in the housing 4a.

[0048] In the utilization heat exchanger 22, heat exchange is performed between the refrigerant flowing inside the utilization heat exchanger 22 and the air in the air-conditioning target space. The utilization heat exchanger 22 is, for example, a fin-and-tube type heat exchanger having a plurality of heat transfer fins and a plurality of heat transfer tubes.

[0049] The heat exchanger 22 has a first connection part 22a and a second connection part 22b, which serve as the inlet and outlet for the refrigerant. By switching the flow path using the flow path switching valve 100, which will be described later, refrigerant flows into the heat exchanger 22 from the first connection part 22a and flows out from the second connection part 22b, both during cooling and heating operation. By ensuring that the refrigerant flows in the same direction inside the heat exchanger 22, it is possible to achieve a state where the airflow direction formed by the fan 24 and the refrigerant flow direction are in opposition, regardless of whether it is cooling or heating operation. As a result, the heat exchange efficiency in the heat exchanger 22 can be maintained at a high level in both cooling and heating operation.

[0050] The utilization fan 24 supplies air taken in from the air-conditioned space to the utilization heat exchanger 22. The utilization fan 24 is, for example, a centrifugal fan such as a turbo fan or a sirocco fan. The utilization fan 24 is driven by a motor (not shown).

[0051] The flow path switching valve 100 switches the direction of refrigerant flow in the heat exchanger 22. Specifically, the flow path switching valve 100 controls the flow of refrigerant so that refrigerant flows in from the first connection part 22a of the heat exchanger 22 and flows out from the second connection part 22b of the heat exchanger 22, both during cooling and heating operation.

[0052] The outer surface of the flow path switching valve 100 (the outer surface 124 of the main casing 120 of the flow path switching valve 100, which will be described later) is provided with a first port 130a, a second port 130b, a third port 130c, and a fourth port 130d to which piping is connected (see Figure 2). The first port 130a, the second port 130b, the third port 130c, and the fourth port 130d are connection points to which piping is connected, and are inlets and outlets for the refrigerant. The gas connecting pipe 8 is connected to the first port 130a (either directly or via other piping). One end of the first pipe 26a is connected to the second port 130b. The other end of the first pipe 26a is connected to the first connection part 22a of the heat exchanger 22. One end of the second pipe 26b is connected to the third port 130c. The other end of the second pipe 26b is connected to the second connection part 22b of the heat exchanger 22. A liquid communication pipe 6 is connected to the fourth port 130d (either directly or via other piping).

[0053] Since the second port 130b is in communication with the first connection part 22a, which is the inlet for the refrigerant of the heat exchanger 22, the refrigerant always flows in the same first flow direction B1 (see Figures 6A and 6B). Since the third port 130c is in communication with the second connection part 22b, which is the outlet for the refrigerant of the heat exchanger 22, the refrigerant always flows in the same second flow direction B2 (see Figures 6A and 6B).

[0054] During cooling operation, the flow path switching valve 100 connects the liquid connecting pipe 6 to the first pipe 26a and the second pipe 26b to the gas connecting pipe 8 (see solid and dashed lines in the flow path switching valve 100 in Figure 7A). During heating operation, the flow path switching valve 100 connects the liquid connecting pipe 6 to the second pipe 26b and the first pipe 26a to the gas connecting pipe 8 (see solid and dashed lines in the flow path switching valve 100 in Figure 7B).

[0055] A specific example of the structure of the flow path switching valve 100 will be described later.

[0056] The utilization unit 4 further includes a utilization control unit (not shown). The utilization control unit includes a control arithmetic unit and a memory device. The control arithmetic unit is a processor such as a CPU and a GPU. The memory device is a storage medium such as RAM, ROM, and flash memory. The control arithmetic unit reads a program stored in the memory device and performs predetermined calculation processing according to the program, and in cooperation with the heat source control unit of the heat source unit 2, controls the operation of various devices of the air conditioner 1 as the control unit 90. The functions of the control unit 90 will be described later.

[0057] (2-2-1) Details of the flow path switching valve A specific example of the structure of the flow path switching valve 100 will be explained with reference to the drawings.

[0058] As shown in Figures 2 to 4, the flow path switching valve 100 mainly comprises a main casing 120, a valve body 140, an drive unit 150, a transmission unit 155, and a sealing member 160.

[0059] The main casing 120 has a cylindrical outer shape. The main casing 120 extends between the first end 125a and the second end 125b in the axial direction of the cylinder. The direction in which the first end 125a and the second end 125b are aligned (the axial direction of the cylinder of the main casing 120) is referred to here as the third arrangement direction A3. The shape of the main casing 120 can be determined as appropriate and is not limited to a cylindrical shape. For example, the outer shape of the main casing 120 may be a rectangular parallelepiped.

[0060] The outer surface 124 of the main casing 120 is provided with a first port 130a, a second port 130b, a third port 130c, and a fourth port 130d, which serve as inlets and outlets for the refrigerant (see Figure 2). In this embodiment, the first port 130a and the fourth port 130d are provided on the second end face 126b of the second end 125b of the cylindrical main casing 120. The second end face 126b may be a flat surface, although this is not limited to it. Also, the second port 130b and the third port 130c are provided on the first end face 126a of the first end 125a of the cylindrical main casing 120. The first end face 126a may be a flat surface, although this is not limited to it. In this embodiment, as shown in Figure 4, the second port 130b and the third port 130c are arranged side by side on the first end face 126a in a predetermined direction (referred to as the first arrangement direction A1). The first arrangement direction A1 is an example of the fourth direction in the claims. Furthermore, the first port 130a and the fourth port 130d are arranged side by side on the second end face 126b in a second arrangement direction A2 that intersects the first arrangement direction A1 (although not limited to this, here it is a direction perpendicular to the first arrangement direction A1, and in Figure 4 it is a direction perpendicular to the plane of the paper). Note that in Figures 6A and 6B, for the sake of ease of understanding the drawings, the first port 130a and the fourth port 130d are depicted as being aligned in the same direction as the second port 130b and the third port 130c.

[0061] The arrangement of the first port 130a, the second port 130b, the third port 130c, and the fourth port 130d may be changed as appropriate. For example, the fourth port 130d may be provided on a side surface (curved surface) near the second end 125b of the main casing 120, rather than on the second end face 126b. Also, for example, the second port 130b and the third port 130c may be arranged side by side along the first arrangement direction A1.

[0062] As shown in Figure 4, a first space V1 is formed inside the main casing 120. The first space V1 is the space in which the valve body 140 is housed. A second flow path R2 through which the refrigerant flows is also formed in the first space V1. A first internal port 122a, a second internal port 122b, a third internal port 122c, and a fourth internal port 122d are provided on the wall surface 122 that forms (surrounds) the first space V1, serving as inlets and outlets for the refrigerant. Here, the first internal port 122a refers to the tip of the hole facing the first space V1. The hole visible when looking at the first internal port 122a from the first space V1 is referred to here as the opening 122ao of the first internal port 122a. The same applies to the second internal ports 122b to the fourth internal ports 122d.

[0063] The first internal port 122a communicates with the first port 130a via a passage (not shown) formed in the main casing 120. The second internal port 122b communicates with the second port 130b via a passage (not shown) formed in the main casing 120. The third internal port 122c communicates with the third port 130c via a passage (not shown) formed in the main casing 120. The fourth internal port 122d communicates with the fourth port 130d via a passage (not shown) formed in the main casing 120.

[0064] As can be seen in Figure 1, the first internal port 122a, which communicates with the first port 130a to which the gas connecting pipe 8 is connected, and the fourth internal port 122d, which communicates with the fourth port 130d to which the liquid connecting pipe 6 is connected, are connected via a heat source heat exchanger 14, through which the refrigerant flowing inside and the heat source fluid exchange heat, without going through the utilization heat exchanger 22. The second internal port 122b, which communicates with the second port 130b to which the first pipe 26a is connected, and the third internal port 122c, which communicates with the third port 130c to which the second pipe 26b is connected, are connected via a utilization heat exchanger 22, through which the refrigerant flowing inside and the air in the space to be air-conditioned exchange heat.

[0065] The inner diameters of the first internal port 122a, the second internal port 122b, and the third internal port 122c are the same (D1). However, this is not limited to the first internal port 122a, the second internal port 122b, and the third internal port 122c may be different. Although not limited to the first internal port 122a, the inner diameter (D2) of the fourth internal port 122d through which liquid refrigerant flows may be smaller than the inner diameter (D1) of the first internal port 122a.

[0066] The valve body 140 is positioned in the first space V1 formed by the main casing 120.

[0067] The valve body 140 is driven by a motor, which is an example of a drive unit 150, and rotates around the rotation axis O. In this embodiment, the rotation axis O extends in a direction perpendicular to the first arrangement direction A1 and the third arrangement direction A3 (here, the second arrangement direction A2) (see Figure 4). The first arrangement direction A1 is the direction in which the second internal port 122b and the third internal port 122c are arranged side by side. Here, as mentioned above, the first arrangement direction A1 is also the direction in which the second port 130b and the third port 130c are arranged side by side. Note that the direction in which the second internal port 122b and the third internal port 122c are arranged and the direction in which the second port 130b and the third port 130c are arranged do not have to be the same, but if the direction in which the second internal port 122b and the third internal port 122c are arranged and the direction in which the second port 130b and the third port 130c are arranged are made to coincide, the structure of the flow path switching valve 100 can be easily simplified. As mentioned above, the third arrangement direction A3 is the direction in which the first end 125a and the second end 125b are aligned (the height direction of the cylindrical main body casing 120).

[0068] Furthermore, the drive unit 150 that rotates the valve body 140 and the shaft 146 (a shaft attached to (integrated with) the valve body 140 for rotating the valve body 140, and supported by a bearing not shown; see Figures 5A and 5B) that extends along the direction of the rotation axis O are connected by a transmission unit 155. In this embodiment, a worm gear is used as the transmission unit 155 as shown in Figure 3. However, the type of transmission mechanism used as the transmission unit 155 (the type of mechanism that transmits the force of the drive unit 150 to the shaft 146) can be selected as appropriate.

[0069] The valve body 140 is rotated by the drive unit 150 around the rotation axis O relative to the main casing 120, and its state is switched between a first state S1 and a second state S2, thereby changing the flow of refrigerant within the flow path switching valve 100.

[0070] Specifically, the valve body 140 forms a first flow path R1 through which the refrigerant flows. In this embodiment, the first flow path R1 includes an internal flow path 144 formed inside the valve body 140 (surrounded by the valve body 140). In this embodiment, the valve body 140 also forms a second flow path R2 in the first space V1, which is different from the first flow path R1. The second flow path R2 is formed by the outer surface of the valve body 140 and the wall surface 122 of the main casing 120 that forms the first space V1. When the drive unit 150 rotates the valve body 140, the port of the main casing 120 through which the first flow path R1 (internal flow path 144) and the second flow path R2 communicate changes, thereby changing the flow of refrigerant within the flow path switching valve 100.

[0071] Specifically, the valve body 140 can rotate around the rotation axis O to enter a first state S1 (see Figure 6B) in which the first internal port 122a and the second internal port 122b are connected by the first flow path R1, and a second state S2 (see Figure 6A) in which the first internal port 122a and the third internal port 122c are connected by the first flow path R1.

[0072] When the valve body 140 is in the first state S1, the third internal port 122c and the fourth internal port 122d are connected by the second flow path R2 (see Figure 6B). When the valve body 140 is in the second state S2, the second internal port 122b and the fourth internal port 122d are connected by the second flow path R2 (see Figure 6A). In the example shown in Figure 6A, the flow of refrigerant appears to be obstructed by the valve body 140, but in reality, the refrigerant flowing in from the fourth internal port 122d flows through the space in front of and behind the valve body 140 in a direction perpendicular to the plane of the paper, which acts as the second flow path R2, and heads toward the second internal port 122b.

[0073] The valve body 140 is ball-shaped. Being ball-shaped means that at least a portion of the outer surface of the valve body is spherical (indicated by reference numeral 141). While the shape of the valve body 140 is not limited, it is hemispherical, with both ends in the direction of the rotation axis O being cut off in a direction perpendicular to the rotation axis O. The internal flow path 144 constituting the first flow path R1 extends through the valve body 140 in a direction intersecting (in this case perpendicular to) the rotation axis O. The spherical surface 141 of the hemispherical valve body 140, the plane 142 located on the opposite side of the spherical surface 141, and the wall surface 122 of the main casing 120 form the second flow path R2.

[0074] The openings 122ao of the first internal port 122a, 122bo of the second internal port 122b, and 122co of the third internal port 122c, to which the internal flow path 144 (first flow path R1) of the valve body 140 is connected, may be provided with a sealing member 160 so as to surround the openings 122ao, 122bo, and 122co. The sealing member 160 is an annular member (packing). The material of the sealing member 160 is not limited, but for example, it is made of a fluororesin such as polytetrafluoroethylene (PTFE). When the valve body 140 rotates around the rotation axis O, the spherical surface 141 of the valve body 140 moves while sliding against the sealing member 160. The material and shape of the sealing member 160 may be selected as appropriate.

[0075] When the valve body 140 takes the first state S1 and the first internal port 122a and the second internal port 122b are connected by the internal flow path 144, the space between the opening 122ao of the first internal port 122a and the valve body 140 is sealed by a sealing member 160 positioned to surround the opening 122ao of the first internal port 122a, and the space between the opening 122bo of the second internal port 122b and the valve body 140 is sealed by a sealing member 160 positioned to surround the opening 122bo of the second internal port 122b. When the valve body 140 takes the second state S2 and the first internal port 122a and the third internal port 122c are connected by the internal flow path 144, the space between the opening 122ao of the first internal port 122a and the valve body 140 is sealed by a sealing member 160 positioned to surround the opening 122ao of the first internal port 122a, and the space between the opening 122co of the third internal port 122c and the valve body 140 is sealed by a sealing member 160 positioned to surround the opening 122co of the third internal port 122c.

[0076] The size of the sealing members 160 provided in the first internal port 122a, the second internal port 122b, and the third internal port 122c may be the same. In particular, it is preferable that the inner diameter of the annular sealing member 160 is the same for the sealing members 160 provided in the first internal port 122a, the second internal port 122b, and the third internal port 122c. Also, the sealing members 160 provided in the first internal port 122a, the second internal port 122b, and the third internal port 122c may be the same (same dimensions and same shape) member.

[0077] Furthermore, when viewing the first internal port 122a, the second internal port 122b, and the third internal port 122c inside the flow path switching valve 100 along the axis of rotation O (in other words, from a direction perpendicular to both the first and third arrangement directions A3), at least a portion of the first internal port 122a is positioned between a virtual line K2 extending from the center C2 of the opening 122bo of the second internal port 122b in the first arrangement direction A1 to the third arrangement direction A3, and a virtual line K3 extending from the center C3 of the opening 122co of the third internal port 122c in the first arrangement direction A1 to the third arrangement direction A3. More preferably, when viewing the first internal port 122a, the second internal port 122b, and the third internal port 122c along the axis of rotation O, at least a portion of the first internal port 122a is positioned between a virtual line (not shown) that passes through the center (not shown) of the opening of the sealing member 160 provided in the opening 122bo of the second internal port 122b in the first arrangement direction A1 and extends to the third arrangement direction A3, and a virtual line (not shown) that passes through the center (not shown) of the opening of the sealing member 160 provided in the opening 122co of the third internal port 122c in the first arrangement direction A1 and extends to the third arrangement direction A3.

[0078] By adopting this structure, the refrigerant can flow smoothly within the flow path switching valve 100 (without significantly changing the direction of refrigerant flow) both when the refrigerant flows from the first port 130a to the second port 130b and when the refrigerant flows from the third port 130c to the first port 130a, thereby suppressing an increase in pressure loss within the flow path switching valve 100.

[0079] In particular, preferably, the center C1 of the opening 122ao of the first internal port 122a in the first arrangement direction A1 is located in the middle of virtual lines K2 and K3 in the first arrangement direction A1. More preferably, the center of the opening of the seal member 160 provided in the opening 122ao of the first internal port 122a in the first arrangement direction A1 is located in the middle of virtual line (not shown) that passes through the center of the opening of the seal member 160 provided in the opening 122bo of the second internal port 122b in the first arrangement direction A1 and extends to the third arrangement direction A3, and virtual line (not shown) that passes through the center of the opening of the seal member 160 provided in the opening 122co of the third internal port 122c in the first arrangement direction A1 and extends to the third arrangement direction A3. Furthermore, when viewed along the axis of rotation O, the axis of rotation O of the valve body 140 is positioned on a virtual line K1 that passes through the center C1 and extends in the third arrangement direction A3.

[0080] By adopting such a structure, the refrigerant can flow particularly smoothly within the flow path switching valve 100, both when the refrigerant flows from the first port 130a to the second port 130b and when the refrigerant flows from the third port 130c to the first port 130a, thereby suppressing an increase in pressure loss within the flow path switching valve 100. Furthermore, with this configuration, when viewed along the rotation axis O, the structure of the main casing 120 on the second internal port 122b side can be made symmetrical to the structure of the main casing 120 on the third internal port 122c side, making it relatively easy to achieve a highly sealing structure between the opening 122bo of the second internal port 122b and the valve body 140, and between the opening 122co of the third internal port 122c and the valve body 140.

[0081] Furthermore, in the flow path switching valve 100, when the valve body 140 is in either the first state S1 or the second state S2, it is preferable that when viewing the main casing 120 from the first end 125a to the second end 125b, the flow of refrigerant through the internal flow path 144 and the flow of refrigerant through the second flow path R2 do not intersect.

[0082] In this context, the intersection of the refrigerant flow in the internal channel 144 and the refrigerant flow in the second channel R2 means that, when viewed from the first end 125a to the second end 125b, the straight line connecting the centers (centers of the port openings) of the ports connected by the internal channel 144 (first port 130a and second port 130b in the first state S1) intersects or overlaps with the straight line connecting the centers (centers of the port openings) of the ports connected by the second channel R2 (third port 130c and fourth port 130d in the first state S1).

[0083] For example, if the first port 130a to the fourth port 130d are arranged as shown in Figures 8A and 8B (in Figures 8A and 8B, the direction in which the second port 130b and the third port 130c are aligned intersects with the direction in which the first port 130a and the fourth port 130d are aligned), whether the valve body 140 is in the first state S1 or the second state S2, the straight line connecting the centers of the ports connected by the internal flow path 144 (see the dashed line in the figure) does not intersect with the straight line connecting the centers of the ports connected by the second flow path R2 (see the dashed line in the figure). In other words, regardless of whether the valve body 140 is in the first state S1 or the second state S2, when viewing the main casing 120 from the first end 125a to the second end 125b, the flow of refrigerant through the internal flow path 144 and the flow of refrigerant through the second flow path R2 do not intersect.

[0084] On the other hand, when the first port 130a to the fourth port 130d are arranged as shown in Figures 9A and 9B (in Figures 9A and 9B, the first port 130a to the fourth port 130d are arranged on the same straight line), if the valve body 140 is in the first state S1, the straight line connecting the centers of the ports connected by the internal flow path 144 (see the dashed line in the figure) and the straight line connecting the centers of the ports connected by the second flow path R2 (see the solid line in the figure) do not intersect (see Figure 9A). However, if the valve body 140 is in the second state S2, the straight line connecting the centers of the ports connected by the internal flow path 144 (see the dashed line in the figure) and the straight line connecting the centers of the ports connected by the second flow path R2 (see the solid line in the figure) intersect (actually overlap). Thus, when the flow of refrigerant through the internal passage 144 and the flow of refrigerant through the second passage R2 intersect, the refrigerant often flows around the valve body 140 (circumvents the valve body 140) from one internal port connected in the second passage R2 to the other internal port, which can potentially lead to a relatively large pressure loss within the flow path switching valve 100.

[0085] (2-3) Control Unit The control unit 90 consists of the heat exchanger 22 used by the heat source unit 2 and the use control unit 4. Note that part or all of the control unit 90 may be composed of devices provided separately from the heat source unit 2 and the use unit 4.

[0086] The control unit 90 controls the operation of the entire air conditioner 1 by causing the control calculation device to execute a program stored in the memory device.

[0087] As shown by the dashed lines in Figure 1, the control unit 90 is electrically connected to the utilization fan 24, the flow path switching valve 100, the compressor 10, the flow path switching mechanism 12, the expansion valve 16, and the heat source fan 15. The control unit 90 is also electrically connected to various sensors (not shown) that measure the temperature and pressure of the refrigerant, the temperature of the air in the air-conditioned space, the outside air temperature, etc. The control unit 90 controls the operation of various components of the air conditioner 1 based on control signals received by the utilization unit 4 from an operating remote control (not shown) and measurement signals from various sensors.

[0088] The control unit 90 primarily performs cooling and heating operations.

[0089] (2-3-1) When the cooling operation control unit 90 receives a command to perform cooling operation from, for example, the operating remote control via the user unit 4, it sets the flow path switching mechanism 12 to the first circuit state and controls the drive unit 150 of the flow path switching valve 100 to set the state of the valve body 140 to the second state S2 (see Figure 6A), and starts the operation of the compressor 10. In addition, based on the measurement results of sensors that measure the temperature and pressure of the refrigerant provided in the refrigerant circuit 50, it appropriately controls the rotation speed of the compressor 10 motor and the opening degree of the expansion valve 16.

[0090] The flow of refrigerant in the refrigerant circuit 50 will be explained with reference to Figure 7A. When the compressor 10 starts operating, the low-pressure gaseous refrigerant in the refrigeration cycle (hereinafter simply referred to as low-pressure) is drawn into the compressor 10 and compressed by the compressor's compression mechanism to become the high-pressure gaseous refrigerant in the refrigeration cycle (hereinafter simply referred to as high-pressure). The high-pressure gaseous refrigerant is sent to the heat source heat exchanger 14 via the flow path switching mechanism 12, where it exchanges heat with the air around the heat source unit 2 supplied by the heat source fan 15 and condenses to become high-pressure liquid refrigerant. The high-pressure liquid refrigerant flows through the liquid pipe 19d, passes through the expansion valve 16, and is reduced in pressure to near the suction pressure of the compressor 10, becoming a gas-liquid two-phase refrigerant. The refrigerant reduced in pressure by the expansion valve 16 is sent to the utilization unit 4 and flows into the flow path switching valve 100. The refrigerant that flows from the liquid connecting pipe 6 into the flow path switching valve 100 via the fourth port 130d and the fourth internal port 122d flows through the second flow path R2 (shown as a dashed line within the flow path switching valve 100 in Figure 7A) and flows into the utilization heat exchanger 22 from the first connection part 22a via the second internal port 122b, the second port 130b and the first pipe 26a. The gas-liquid two-phase refrigerant that flows into the utilization heat exchanger 22 exchanges heat with the air of the air-conditioned space supplied to the utilization heat exchanger 22 by the utilization fan 24 and evaporates, becoming a low-pressure gaseous refrigerant. The low-pressure gaseous refrigerant flowing out of the utilization heat exchanger 22 flows out from the second connection part 22b and flows into the flow path switching valve 100 from the third port 130c via the second pipe 26b. The refrigerant flowing into the flow path switching valve 100 flows through the internal flow path 144 of the valve body 140 (first flow path R1, shown as a solid line within the flow path switching valve 100 in Figure 7A) from the third internal port 122c, and flows out to the gas connecting pipe 8 via the first internal port 122a and the first port 130a. The refrigerant is then sent to the heat source unit 2 via the gas connecting pipe 8 and flows into the accumulator 18 via the flow path switching mechanism 12. The low-pressure gaseous refrigerant that flows into the accumulator 18 is then drawn back into the compressor 10. The temperature of the air supplied to the utilization heat exchanger 22 decreases by heat exchange with the refrigerant flowing through the utilization heat exchanger 22, and the cooled air is blown into the air-conditioned space.

[0091] (2-3-2) When the heating operation control unit 90 receives a command to perform heating operation from, for example, the operating remote control via the user unit 4, it sets the flow path switching mechanism 12 to the second circuit state and controls the drive unit 150 of the flow path switching valve 100 to set the state of the valve body 140 to the first state S1 (see Figure 6B), and starts the operation of the compressor 10. It also appropriately controls the rotation speed of the compressor 10 motor and the opening degree of the expansion valve 16 based on the measurement results of sensors that measure the temperature and pressure of the refrigerant, which are provided in the refrigerant circuit 50.

[0092] The flow of refrigerant in the refrigerant circuit 50 will be explained with reference to Figure 7B. When the compressor 10 is started, low-pressure gaseous refrigerant is drawn into the compressor 10 and compressed by the compressor 10 to become high-pressure gaseous refrigerant. The high-pressure gaseous refrigerant is sent to the utilization unit 4 via the flow path switching mechanism 12 and flows into the flow path switching valve 100. The gaseous refrigerant that has flowed into the flow path switching valve 100 from the gas connecting pipe 8 via the first port 130a and the first internal port 122a flows through the first flow path R1 (shown as a solid line in the flow path switching valve 100 in Figure 7B) and flows into the utilization heat exchanger 22 from the first connection part 22a via the second internal port 122b, the second port 130b and the first pipe 26a. The gaseous refrigerant sent to the utilization heat exchanger 22 exchanges heat with the air of the air-conditioned space supplied to the utilization heat exchanger 22 by the utilization fan 24 and condenses to become high-pressure liquid refrigerant. The temperature of the air supplied to the utilization heat exchanger 22 rises as it exchanges heat with the refrigerant flowing through the utilization heat exchanger 22, and the heated air is blown out into the space to be air-conditioned. The high-pressure liquid refrigerant flowing out from the utilization unit 4 flows out from the second connection part 22b and flows through the second pipe 26b to the flow path switching valve 100 from the third port 130c. The refrigerant that has flowed into the flow path switching valve 100 flows from the third internal port 122c to the second flow path R2 (shown as a dashed line within the flow path switching valve 100 in Figure 7B), and flows out to the liquid connecting pipe 6 via the fourth internal port 122d and the fourth port 130d. The high-pressure liquid refrigerant that has flowed out into the liquid connecting pipe 6 flows into the heat source unit 2. The refrigerant flowing into the heat source unit 2 flows through the liquid pipe 19d and, as it flows through the expansion valve 16, is reduced in pressure to near the suction pressure of the compressor 10, becoming a gas-liquid two-phase refrigerant, which then flows into the heat source heat exchanger 14. The low-pressure gas-liquid two-phase refrigerant flowing into the heat source heat exchanger 14 exchanges heat with the air surrounding the heat source unit 2 supplied by the heat source fan 15, evaporates, and becomes a low-pressure gaseous refrigerant. The low-pressure gaseous refrigerant flows into the accumulator 18 via the flow path switching mechanism 12. The low-pressure gaseous refrigerant flowing into the accumulator 18 is then drawn back into the compressor 10.

[0093] (3) Features (3-1) An air conditioner 1 according to an example of a refrigeration cycle device is equipped with a refrigerant circuit 50. In the refrigerant circuit 50, a compressor 10, a utilization heat exchanger 22 which is an example of a first heat exchanger, an expansion valve 16, and a heat source heat exchanger 14 which is an example of a second heat exchanger are connected by refrigerant piping. The air conditioner 1 is equipped with a flow path switching valve 100 and a control unit 90. The flow path switching valve 100 has a main casing 120, a valve body 140, and a drive unit 150. A first space V1 is formed inside the main casing 120. A first port 130a, a second port 130b, a third port 130c, and a fourth port 130d are provided on the outer surface 124 of the main casing 120, which serve as inlets and outlets for the refrigerant. The valve body 140 is arranged inside the first space V1. The valve body 140 forms a first flow path R1 through which the refrigerant flows. The drive unit 150 drives the valve body 140. The control unit 90 controls the drive unit 150. The control unit 90 controls the drive unit 150 to switch the state of the valve body 140 between a first state S1 and a second state S2. When the valve body 140 is in the first state S1, the first port 130a and the second port 130b are connected by the first flow path R1. When the valve body 140 is in the second state S2, the first port 130a and the third port 130c are connected by the first flow path R1. In the second port 130b, the refrigerant always flows in the same first flow direction (first direction) B1. In the third port 130c, the refrigerant always flows in the same second flow direction (second direction) B2. The main casing 120 has a first end 125a and a second end 125b. The first end 125a of the main casing 120 is provided with a second port 130b and a third port 130c, and the second end 125b of the main casing 120 is provided with a first port 130a.

[0094] In this air conditioner 1, even when the state of the valve body 140 is switched between the first state S1 and the second state S2, as shown in Figures 6A and 6B, the refrigerant flowing into or out of the first port 130a always flows in the same direction (up and down in Figures 6A and 6B) without reversing direction. Therefore, in the air conditioner 1, the refrigerant flowing into or out of the first port 130a does not reverse direction within the valve body 140, and the decrease in Cv value (reduction of pressure loss) that would occur due to the refrigerant reversing direction within the valve body 140 is suppressed, thereby realizing an efficient air conditioner 1.

[0095] (3-2) In the air conditioner 1, the first flow path R1 includes an internal flow path 144 formed inside the valve body 140. The valve body 140 forms a second flow path R2, which is different from the first flow path R1, in the first space V1. The internal flow path 144 connects the first port 130a and the second port 130b in the first state S1, and connects the first port 130a and the third port 130c in the second state S2. The second flow path R2 connects the third port 130c and the fourth port 130d when the valve body 140 is in the first state S1, and connects the second port 130b and the fourth port 130d when the valve body 140 is in the second state S2.

[0096] In this air conditioner 1, in addition to the internal flow path 144 formed inside the valve body 140, a second flow path R2 outside the valve body 140 is used as the refrigerant flow path, thereby making the valve body 140 smaller and realizing a compact flow path switching valve 100.

[0097] However, although it is preferable to use the first space V1 outside the valve body 140 as a refrigerant flow path, the second flow path R2 may also be formed inside the valve body 140 instead of inside it. In this case, for example, the inner diameter of the fourth internal port 122d and the inner diameter of the first internal port 122a may be the same, and a sealing member 160 may also be provided in the fourth internal port 122d.

[0098] (3-3) In the air conditioner 1, when the valve body 140 is in either the first state S1 or the second state S2, when viewing the main casing 120 from the first end 125a to the second end 125b, the flow of refrigerant through the internal passage 144 and the flow of refrigerant through the second passage do not intersect.

[0099] In the air conditioner 1, by arranging the first port 130a to the fourth port 130d to satisfy the above conditions, the refrigerant can flow smoothly (without taking a roundabout route that bypasses the valve body 140), and pressure loss within the flow path switching valve 100 can be reduced.

[0100] (3-4) In the air conditioner 1, the main casing 120 is provided with a wall surface 122 forming the first space V1, a first internal port 122a communicating with the first port 130a, a second internal port 122b communicating with the second port 130b, and a third internal port 122c communicating with the third port 130c. When viewing the first internal port 122a, the second internal port 122b, and the third internal port 122c from a direction perpendicular to the first arrangement direction A1 in which the second internal port 122b and the third internal port 122c are arranged side by side, and perpendicular to the third arrangement direction (third direction) A3 in which the first end 125a and the second end 125b are aligned, at least a portion of the first internal port 122a is positioned between a virtual line K2 extending in the third arrangement direction A3 through the center C2 of the opening 122bo of the second internal port 122b and a virtual line K3 extending in the third arrangement direction A3 through the center C3 of the opening 122co of the third internal port 122c.

[0101] In this air conditioner 1, by arranging the first port 130a to the third port 130c in a manner that satisfies the above conditions, the refrigerant can flow smoothly (without taking a roundabout route) through the internal flow path 144 in the first state S1 and the second state S2, thereby reducing pressure loss within the flow path switching valve 100.

[0102] (3-5) The air conditioner 1 is equipped with a sealing member 160. The sealing member 160 is provided so as to surround the opening 122ao of the first internal port 122a, the opening 122bo of the second internal port 122b, and the opening 122co of the third internal port 122c. When the first internal port 122a, the second internal port 122b, and the third internal port 122c are connected to the internal flow path 144, the sealing member 160 seals the space between the openings 122ao, 122bo, and 122co of the internal ports 122a, 122b, and 122c connected to the internal flow path 144 and the valve body 140.

[0103] In the air conditioner 1, when each internal port 122a, 122b, and 122c is connected to the internal flow path 144 of the valve body 140, situations in which refrigerant flows out from the internal ports 122a, 122b, and 122c connected by the internal flow path 144 into the first space V1 around the valve body 140, or refrigerant flows in from the first space V1 around the valve body 140 into the internal ports 122a, 122b, and 122c connected by the internal flow path 144, can be suppressed, thereby realizing an efficient air conditioner 1.

[0104] (3-6) In the air conditioner 1, the fourth port 130d is preferably located at the second end 125b of the main casing 120.

[0105] In this air conditioner 1, the refrigerant flowing into or out of the fourth port 130d flows between the first end 125a and the second end 125b in the same direction (up and down in Figures 6A and 6B) without folding back, as shown in Figures 6A and 6B. Therefore, in this air conditioner 1, the decrease in the Cv value due to the refrigerant folding back within the valve body 140 when flowing into or out of the fourth port 130d is eliminated (pressure loss is reduced), thereby realizing an efficient air conditioner 1.

[0106] However, the design is not limited to this, and the fourth port 130d, through which the liquid refrigerant mainly flows, may be located in a place other than the second end 125b of the main casing 120, for example, on the side of the main casing 120, on the side closer to the second end 125b than the first end 125a in the third arrangement direction A3.

[0107] (3-7) In the air conditioner 1, the second port 130b and the third port 130c are arranged side by side at the first end 125a of the main casing 120 in a first arrangement direction A1, which is an example of a fourth direction. At the second end 125b of the main casing 120, the first port 130a and the fourth port 130d are arranged side by side in a direction intersecting the first arrangement direction A1. For example, although not limited to this, the first port 130a and the fourth port 130d are arranged side by side in a second arrangement direction A2 that is perpendicular to the first arrangement direction A1.

[0108] In the air conditioner 1, by arranging the first port 130a to the fourth port 130d to satisfy the above conditions, the refrigerant can flow smoothly (without taking a roundabout route) through the internal flow path 144 in the first state S1 and the second state S2, thereby reducing pressure loss within the flow path switching valve 100.

[0109] (3-8) In the air conditioner 1, the drive unit 150 rotates the valve body 140 around the rotation axis O and switches the state of the valve body 140 between a first state S1 and a second state S2.

[0110] In the air conditioner 1, different flow path connection states can be achieved with a relatively simple flow path switching valve 100.

[0111] (3-9) In the air conditioner 1, the inner diameter D2 of the fourth port 130d is smaller than the inner diameter D1 of the first port 130a.

[0112] In the air conditioner 1, the inner diameter D2 of the fourth port 130d is smaller than that of the first port 130a, which increases the flexibility of the placement of the fourth port 130d. Furthermore, by reducing the diameter of the refrigerant piping that communicates with the fourth port 130d to match the inner diameter of the fourth port 130d, the flexibility of the piping route of the refrigerant piping connected to the flow path switching valve 100 can be increased.

[0113] (3-10) In the air conditioner 1, the second port 130b and the third port 130c are arranged on a plane (first end face 126a) provided at the first end 125a of the main casing 120.

[0114] In this air conditioner 1, by arranging the second port 130b and the third port 130c on the same plane, the routing of the piping connected to the second port 130b and the third port 130c can be simplified.

[0115] Furthermore, the installation location of the second port 130b and the third port 130c is not limited to a flat surface, as long as they are arranged side by side on the first end side of the main casing. The second port 130b and the third port 130c may be arranged on a curved surface (for example, side by side vertically on the side of the main casing 120). The first port 130a (and preferably the fourth port 130d as well) may be located on the back side of the main casing 120 where the second port 130b and the third port 130c are provided.

[0116] (3-11) In the air conditioner 1, the second port 130b communicates with the first connection part 22a, which is the inlet for the refrigerant of the utilization heat exchanger 22, where heat exchange takes place between the refrigerant flowing inside and the air in the space to be air-conditioned. The third port 130c communicates with the second connection part 22b, which is the outlet for the refrigerant of the utilization heat exchanger 22. The utilization heat exchanger 22 and the flow path switching valve 100 are housed inside the housing 4a.

[0117] A common technical challenge is that the housing 4a of the utilization unit 4 should be as compact as possible. However, if the routing of the piping connecting the utilization heat exchanger 22 and the flow path switching valve 100 becomes complex, it may be difficult to make such a housing 4a compact.

[0118] In contrast, in the air conditioner 1, the second port 130b and the third port 130c are located at the same end (first end 125a) of the main casing 120, which simplifies the routing of the piping connecting the heat exchanger 22 and the flow path switching valve 100. As a result, the size of the housing 4a that accommodates the heat exchanger 22 and the flow path switching valve 100 can be kept to a minimum.

[0119] (4) Modifications The following are modifications of the above embodiments. The modifications shown below may be combined as appropriate, as long as they do not contradict each other.

[0120] (4-1) Modification A In the above embodiment, a flow path switching mechanism 12 may be used, which may be a flow path switching valve having the same structure as the flow path switching valve 100. When a flow path switching valve having the same structure as the flow path switching valve 100 is used in the flow path switching mechanism 12, for example, an intake pipe 19a is connected to the second port, a discharge pipe 19b is connected to the third port, a first gas pipe 19c is connected to the first port, and a liquid pipe 19d is connected to the fourth port. The diameter of the ports should be selected to a size suitable for use as a flow path switching mechanism 12.

[0121] (4-2) Modification B In the above embodiment, an example was described in which the valve body 140 of the flow path switching valve 100 is ball-shaped, and the state of the valve body 140 is changed by rotating the valve body 140. However, it is not limited to this.

[0122] For example, a flow path switching valve may have a valve body consisting of multiple plates, each having a hole that forms a first flow path R1 and a notch that forms a second flow path R2. By rotating the multiple plates around a rotation axis perpendicular to the plates, the relative positional relationship of the holes and notches of the multiple plates is changed to realize the connection state between ports through the first flow path R1 and the second flow path R2 as described above (the flow path switching valve may be of the revolver type). Alternatively, a flow path switching valve may have a valve body consisting of multiple plates, each having a hole that forms a first flow path R1 and a notch that forms a second flow path R2. By sliding the multiple plates, the relative positional relationship of the holes and notches of the multiple plates is changed to realize the connection state between ports through the first flow path R1 and the second flow path R2 as described above.

[0123] (4-3) Modification C In the above embodiment, an example was described in which the flow path switching valve 100 is provided in the utilization unit 4, but the location in which the flow path switching valve 100 is installed is not limited to within the utilization unit 4. The flow path switching valve 100 may be provided in the heat source unit 2, or it may be provided separately in the connecting pipes 6 and 8 from the heat source unit 2 and the utilization unit 4.

[0124] (4-4) Modification D In the above embodiment, an example has been described in which an internal flow path 144 formed inside the valve body 140 of the flow path switching valve 100 functions as a first flow path R1. However, it is not limited to this, and at least a part of the first flow path R1 may be a passage formed by the valve body 140 and the wall surface 122 of the main casing 120, which is separate from the second flow path R2.

[0125] <Note> Although embodiments of this disclosure have been described above, it should be understood that various modifications to the form and details are possible without departing from the spirit and scope of this disclosure as described in the claims.

[0126] 1 Refrigeration cycle device 4a Housing 10 Compressor 14 Heat source heat exchanger (second heat exchanger) 16 Expansion valve 22 Utilization heat exchanger (first heat exchanger) 22a First connection part 22b Second connection part 50 Refrigerant circuit 90 Control unit (control device) 100 Flow path switching valve 120 Main casing 122 Wall surface 122a First internal port 122ao Opening 122b Second internal port 122bo Opening 122c Third internal port 122co Opening 122d Fourth internal port 124 Outer surface 125a First end 125b Second end 126a First end surface (planar) 126b Second end surface (planar) 130a First port 130b Second port 130c Third port 130d 4th port 140 Valve body 144 Internal flow path 150 Drive unit 160 Seal member A1 First arrangement direction (direction in which the second and third internal ports are arranged side by side, fourth direction) A2 Second arrangement direction (direction intersecting the fourth direction) A3 Third arrangement direction (third direction) B1 First flow direction (first direction) B2 Second flow direction (second direction) C2 Center of the opening of the second internal port C3 Center of the opening of the third internal port D1 Inner diameter of the first port D2 Inner diameter of the fourth port K2 Imaginary line passing through the center of the opening of the second internal port K3 Imaginary line passing through the center of the opening of the third internal port O Rotation axis R1 First flow path R2 Second flow path S1 First state S2 Second state V1 First space

[0127] Japanese Patent Publication No. 2010-112517

Claims

1. A refrigeration cycle device comprising a compressor (10), a first heat exchanger (22), an expansion valve (16), and a second heat exchanger (14), connected by refrigerant piping in a refrigerant circuit (50), the device comprising: a main casing (120) having a first space (V1) formed inside and a first port (130a), a second port (130b), a third port (130c), and a fourth port (130d) on its outer surface (124) which serve as inlets and outlets for the refrigerant; a flow path switching valve (100) having a valve body (140) disposed inside the first space and forming a first flow path (R1) through which the refrigerant flows, and a drive unit (150) that drives the valve body; and a control device (90) that controls the drive unit. The control device controls the drive unit to switch the state of the valve body between a first state (S1) in which the first port and the second port are connected by the first flow path and a second state (S2) in which the first port and the third port are connected by the first flow path, the refrigerant always flows in the same first direction (B1) through the second port, the refrigerant always flows in the same second direction (B2) through the third port, the main casing has a first end (125a) and a second end (125b), the second port and the third port are located at the first end of the main casing, and the first port is located at the second end of the main casing, the refrigeration cycle device (1).

2. The refrigeration cycle apparatus according to claim 1, wherein the first flow path includes an internal flow path (144) formed inside the valve body, the valve body further forms a second flow path (R2) different from the first flow path in the first space (V1), the internal flow path connects the first port and the second port in the first state, and connects the first port and the third port in the second state, the second flow path connects the third port and the fourth port when the valve body is in the first state, and connects the second port and the fourth port when the valve body is in the second state.

3. When the valve body is in either the first or second state, when the main casing is viewed from the first end to the second end, the flow of the refrigerant through the internal passage and the flow of the refrigerant through the second passage do not intersect, as described in claim 2.

4. The main casing is provided with a wall surface (122) forming the first space, a first internal port (122a) communicating with the first port, a second internal port (122b) communicating with the second port, and a third internal port (122c) communicating with the third port, and when viewing the first internal port, the second internal port, and the third internal port from a direction perpendicular to the direction (A1) in which the second internal port and the third internal port are arranged side by side, and perpendicular to the third direction (A3) in which the first end and the second end are aligned, at least a part of the first internal port is positioned between a virtual line (K2) extending in the third direction passing through the center (C2) of the opening (122bo) of the second internal port and a virtual line (K3) extending in the third direction passing through the center (C3) of the opening (122co) of the third internal port. The refrigeration cycle apparatus according to any one of claims 1 to 3.

5. The refrigeration cycle apparatus according to claim 4, further comprising a sealing member (160) provided so as to surround the opening of the first internal port (122ao), the opening of the second internal port, and the opening of the third internal port, and sealing the space between the opening and the valve body when the first internal port, the second internal port, and the third internal port are connected to the internal flow path.

6. The refrigeration cycle apparatus according to any one of claims 1 to 5, wherein the fourth port is located at the second end of the main casing.

7. The refrigeration cycle apparatus according to claim 6, wherein the second port and the third port are arranged side by side in a fourth direction (A1) at the first end of the main casing, and the first port and the fourth port are arranged side by side in a direction (A2) intersecting the fourth direction at the second end of the main casing.

8. The refrigeration cycle apparatus according to any one of claims 1 to 7, wherein the drive unit rotates the valve body around a rotation axis (O) to switch the state of the valve body between the first state and the second state.

9. The refrigeration cycle apparatus according to any one of claims 1 to 8, wherein the inner diameter (D2) of the fourth port is smaller than the inner diameter (D1) of the first port.

10. The refrigeration cycle apparatus according to any one of claims 1 to 9, wherein the second port and the third port are arranged on a plane (126a) provided at the first end of the main casing.

11. The refrigeration cycle device is an air conditioner, wherein the second port communicates with a first connection part (22a) which is the inlet for the refrigerant of a first heat exchanger in which heat exchange takes place between the refrigerant flowing inside and the air of the space to be air-conditioned, the third port communicates with a second connection part (22b) which is the outlet for the refrigerant of the first heat exchanger, and the first heat exchanger and the flow path switching valve are housed inside a housing (4a), the refrigeration cycle device according to any one of claims 1 to 10.

12. The refrigeration cycle apparatus according to any one of claims 1 to 11, wherein the valve body is ball-shaped with at least a portion of its outer surface being spherical.