Heat source machine and refrigeration cycle device

Abstract

A heat source machine (2) comprises a refrigerant circuit (20), a refrigerant container (44), a connection part (43), a communication pipe (42), and a protection member (46). The refrigerant circuit (20) includes a compressor (21) and a heat exchanger (23). The refrigerant container (44) is connected to the refrigerant circuit (20). The refrigerant container (44) is filled with a combustible refrigerant. The connection part (43) is connected to the refrigerant container (44). The communication pipe (42) connects the connection part (43) and the refrigerant circuit (20). The protection member (46) protects the connection part (43).

Description

Heat source machine and refrigeration cycle device

[0001] This relates to a heat source machine and a refrigeration cycle device.

[0002] Patent Document 1 (JP 2000-28237 A) discloses a refrigeration cycle device in which a cassette-type special pressure vessel filled with the required amount of flammable refrigerant gas is used to fill the refrigeration cycle through the intake side piping of the compressor.

[0003] However, the above-mentioned Patent Document 1 does not disclose how to install the special pressure vessel for charging and recovering the refrigerant.

[0004] A heat source unit according to a first aspect includes a refrigerant circuit, a refrigerant container, a connection portion, a communication pipe, and a protective member. The refrigerant circuit includes a compressor and a heat exchanger. The refrigerant container is connected to the refrigerant circuit. The refrigerant container is filled with a flammable refrigerant. The connection portion is connected to the refrigerant container. The communication pipe connects the connection portion and the refrigerant circuit. The protective member protects the connection portion.

[0005] According to the heat source apparatus of the first aspect, the protective member protects the connection portion connected to the refrigerant container filled with the flammable refrigerant, thereby suppressing damage to the connection portion and improving safety.

[0006] A heat source machine according to a second aspect is the heat source machine according to the first aspect, wherein the connection portion has a connection valve that opens and closes the communication pipe, and the protective member protects the connection valve.

[0007] In the heat source machine of the second aspect, the connection valve can be protected by the protective member, and therefore safety can be further improved.

[0008] A heat source machine according to a third aspect is the heat source machine according to the first or second aspect, wherein the protective member has an opening.

[0009] In the heat source machine of the third aspect, work can be performed through the opening in the protective member, thereby improving workability.

[0010] A heat source machine according to a fourth aspect is the heat source machine according to the third aspect, wherein the opening is provided on the maintenance side.

[0011] In the heat source machine of the fourth aspect, the opening of the protective part is provided on the maintenance side, so that maintenance of the connection part can be easily carried out.

[0012] A heat source machine according to a fifth aspect is the heat source machine according to any one of the first aspect to the fourth aspect, wherein the connection portion is provided at a lower portion of the refrigerant container.

[0013] In the heat source machine according to the fifth aspect, the connection portion is provided at the bottom of the refrigerant container, so that the flammable refrigerant flows from the bottom of the refrigerant container to the refrigerant circuit, thereby improving the dischargeability of refrigeration oil contained in the refrigerant.

[0014] A sixth aspect of the present invention relates to the heat source machine of the fifth aspect, further comprising a casing and a base. The casing houses the compressor, the heat exchanger, the refrigerant container, the connection portion, the connecting pipe, and the protective member. The base is disposed on a bottom plate of the casing. The base is in contact with the protective member.

[0015] As in the heat source apparatus of the sixth aspect, the refrigerant container may be fixed to the bottom plate of the casing via a base and a protective member.

[0016] A heat source machine according to a seventh aspect is the heat source machine according to the sixth aspect, wherein the base is fixed to a protective member.

[0017] In the heat source unit of the seventh aspect, the protective member is fixed to the base that is placed on the bottom plate of the casing, and therefore the connecting portion can be more appropriately protected by the protective member.

[0018] The heat source apparatus according to an eighth aspect is the heat source apparatus according to the sixth or seventh aspect, wherein the base has an elastic member. The elastic member is in contact with the bottom plate.

[0019] In the heat source apparatus of the eighth aspect, even if the refrigerant container is dropped, the elastic member can prevent the refrigerant container from being damaged.

[0020] A heat source machine according to a ninth aspect is the heat source machine according to any one of the first to eighth aspects, further comprising a buffer material. The buffer material is attached to the refrigerant container.

[0021] In the heat source apparatus of the ninth aspect, the refrigerant container can be protected by the buffer material when an impact such as a drop is applied.

[0022] A heat source machine according to a tenth aspect is the heat source machine according to any one of the first aspect to the ninth aspect, wherein the communication pipe is connected to the low-pressure side of the refrigerant circuit.

[0023] As in the heat source apparatus of the tenth aspect, the refrigerant container may be connected to the low-pressure side of the refrigerant circuit via a communication pipe and a connection part.

[0024] The heat source machine of an eleventh aspect is the heat source machine of any one of the first aspect to the tenth aspect, wherein the connecting pipe has a capillary.

[0025] In the heat source apparatus of the eleventh aspect, the capillary can reduce the load applied to the connection portion.

[0026] A heat source machine according to a twelfth aspect is the heat source machine according to any one of the first aspect to the eleventh aspect, wherein the protective member has a thickness of 2 mm or more and 10 mm or less.

[0027] In the heat source unit of the twelfth aspect, the thickness of the protective member is 2 mm or more and 10 mm or less, so the protective member is strong. Therefore, damage to the connection portion can be further suppressed.

[0028] A heat source machine according to a thirteenth aspect is the heat source machine according to any one of the first to twelfth aspects, in which the protection member is integral with the refrigerant container.

[0029] In the heat source apparatus of the thirteenth aspect, the protective member and the refrigerant container are stably fixed together, which makes it possible to further prevent damage to the connection portion protected by the protective member.

[0030] A refrigeration cycle apparatus according to a fourteenth aspect includes a heat source machine and a utilization machine. The heat source machine is any one of the heat source machines according to the first aspect to the thirteenth aspect. The utilization machine is connected to the heat source machine.

[0031] According to the refrigeration cycle apparatus of the fourteenth aspect, the refrigerant circuit can be filled with a flammable refrigerant from a stably arranged refrigerant container, thereby improving safety.

[0032] It is a schematic configuration diagram of a refrigeration cycle device including a heat source unit according to an embodiment of the present disclosure. It is a cross-sectional schematic diagram of the heat source unit. It is a perspective view of the vicinity of a refrigerant container in the heat source unit. It is a diagram in which a protective member and a buffer material are omitted from FIG. 3. It is a schematic diagram of the vicinity of a refrigerant container in the heat source unit.

[0033] (1) Refrigeration Cycle Apparatus As shown in Fig. 1 , a refrigeration cycle apparatus 1 according to an embodiment of the present disclosure includes a heat source unit 2 and a utilization unit 3. The heat source unit 2 and the utilization unit 3 are connected to each other.

[0034] The heat source unit 2 has a refrigerant circuit 20 through which a flammable refrigerant circulates. The utilization unit 3 has a water circuit 30 through which water circulates. The refrigeration cycle device 1 causes the refrigerant circuit 20 to perform a vapor compression refrigeration cycle to heat or cool the water circulating through the water circuit 30, and uses this water to perform heating and cooling operations in a target space.

[0035] (2) Heat Source Unit In the following description, expressions indicating directions such as "up," "down," "front," "rear," "left," and "right" are used as appropriate, but these refer to the directions when the heat source unit 2 is installed outdoors and in normal use. In this embodiment, the up and down direction is the vertical direction.

[0036] The heat source unit 2 is placed in a space different from the space to be heated or cooled. Here, the heat source unit 2 is installed outdoors (on the roof of a building, near the exterior wall of a building, etc.).

[0037] The heat source unit 2 includes a refrigerant circuit 20, a fan 23a, a refrigerant container 44, a connection unit 43, a communication pipe 42, a control unit 4, and a casing 41 shown in Fig. 2. The heat source unit 2 shown in Fig. 1 further includes a portion of a water circuit 30.

[0038] (2-1) Refrigerant Circuit The refrigerant circuit 20 is a circuit through which a refrigerant circulates during normal operation such as heating operation or cooling operation. The refrigerant circuit 20 is filled with a flammable refrigerant (hereinafter also referred to as "refrigerant") during normal operation. The flammable refrigerant is a refrigerant that is combustible. Examples of the flammable refrigerant include hydrocarbon refrigerants such as R1234yf, R1234ze, and R32. In this example, the refrigerant is a refrigerant classified as highly flammable (A3) according to ISO 817, and is R290 (propane) in this embodiment. The refrigerant includes refrigerating machine oil. Examples of the refrigerating machine oil include PAG (polyalkylene glycol).

[0039] The refrigerant circuit 20 includes a compressor 21, a four-way switching valve 22, a first heat exchanger 23, a pressure reducing valve 24, a second heat exchanger 25, a liquid-gas heat exchanger 26, an accumulator 27, a gas injection valve 28, and an economizer heat exchanger 29.

[0040] (2-1-1) Compressor The compressor 21 is a device for compressing a refrigerant. The compressor 21 has a suction port 21a, an injection port 21b, and a discharge port 21c. The refrigerant flows into the compressor 21 through the suction port 21a, is compressed to a high temperature and high pressure, and flows out from the discharge port 21c. The refrigerant can also flow into the compressor 21 through the injection port 21b during the compression process.

[0041] (2-1-2) Four-way switching valve The four-way switching valve 22 switches the flow of refrigerant so that the second heat exchanger 25 functions as an evaporator and the first heat exchanger 23 functions as a radiator during cooling operation. Also, the four-way switching valve 22 switches the flow of refrigerant so that the second heat exchanger 25 functions as a radiator and the first heat exchanger 23 functions as an evaporator during heating operation.

[0042] Specifically, during cooling operation, the four-way switching valve 22 connects the discharge port 21c of the compressor 21 to the first heat exchanger 23, and also connects the suction port 21a of the compressor 21 to the second heat exchanger 25. During heating operation, the four-way switching valve 22 connects the discharge port 21c of the compressor 21 to the second heat exchanger 25, and also connects the suction port 21a of the compressor 21 to the first heat exchanger 23.

[0043] (2-1-3) First Heat Exchanger The first heat exchanger 23 is an air heat exchanger. The first heat exchanger 23 exchanges heat between the refrigerant flowing inside and the outside air (outdoor air) sent from the fan 23 a. A heat exchanger suitable for the application, such as a cross-fin heat exchanger or a microchannel heat exchanger, is used as the first heat exchanger 23.

[0044] (2-1-4) Pressure Reducing Valve The pressure reducing valve 24 is an electric expansion valve. The liquid refrigerant flowing through the pressure reducing valve 24 expands to a gas-liquid two-phase state, thereby reducing the pressure and temperature of the refrigerant. The pressure reducing valve 24 controls the flow rate of the refrigerant passing through it by adjusting the valve opening.

[0045] (2-1-5) Second Heat Exchanger The second heat exchanger 25 is a water heat exchanger. In this embodiment, the second heat exchanger 25 exchanges heat between the refrigerant flowing through the refrigerant circuit 20 and the water flowing through the water circuit 30. A heat exchanger suitable for the application, such as a plate heat exchanger, is used as the second heat exchanger 25.

[0046] (2-1-6) Liquid-gas heat exchanger During heating operation, the liquid-gas heat exchanger 26 exchanges heat between the high-pressure refrigerant that has left the refrigerant outlet of the second heat exchanger 25 and the low-pressure refrigerant that is flowing from the refrigerant outlet of the first heat exchanger 23 toward the suction port of the compressor 21.

[0047] (2-1-7) Accumulator The accumulator 27 is connected between the four-way switching valve 22 and the suction port 21a of the compressor 21. The accumulator 27 recovers the liquid refrigerant that was not gasified in the evaporator, and prevents the liquid refrigerant from flowing into the suction port 21a of the compressor 21.

[0048] (2-1-8) Gas Injection Valve The gas injection valve 28 is, for example, an on / off valve such as a solenoid valve, or a flow control valve such as an electric expansion valve. In this embodiment, the gas injection valve 28 is an electric expansion valve.

[0049] (2-1-9) Economizer Heat Exchanger The economizer heat exchanger 29 is configured to perform heat exchange between the high-temperature liquid refrigerant flowing out of the second heat exchanger 25 and the refrigerant in a gas-liquid two-phase state flowing out of the gas injection valve 28 during heating operation. As a result, the liquid refrigerant from the second heat exchanger 25 is subcooled during heating operation.

[0050] A solenoid valve 32 is connected between a refrigerant flow path 31 connecting the second heat exchanger 25 and the pressure reducing valve 24 and the economizer heat exchanger 29. The solenoid valve 32 is closed during cooling operation, and the refrigerant does not flow to the economizer heat exchanger 29 or the liquid-gas heat exchanger 26.

[0051] (2-2) Fan The fan 23a flows outside air through the first heat exchanger 23. The fan 23a is driven by a fan motor.

[0052] (2-3) Casing The casing 41 shown in FIG. 2 accommodates the refrigerant circuit 20, the fan 23a, the refrigerant container 44, the connection portion 43, and the connecting pipe .

[0053] The casing 41 has a substantially rectangular parallelepiped shape and includes a front panel 411 , a top panel 412 , a bottom panel 413 , and side panels 414 .

[0054] The front plate 411 is a plate-like member that forms the front surface of the casing 41. An air outlet is formed in the front plate 411. The air outlet is an opening for blowing outside air that has been taken in from the outside of the casing 41 to the inside of the casing 41 out to the outside of the casing 41.

[0055] The top plate 412 is a plate-like member that forms the upper surface of the casing 41. The bottom plate 413 is a plate-like member that forms the lower surface of the casing 41. The top plate 412 and the bottom plate 413 face each other.

[0056] The side plates 414 are plate-like members that form the side surfaces of the casing 41. The side plates have a left side plate and a right side plate. The lower portions of the side plates 414 are fixed to the bottom plate 413.

[0057] The casing 41 further includes a partition plate 415. The partition plate 415 is a plate-shaped member that extends in the vertical direction. A lower portion of the partition plate 415 is fixed to the bottom plate 413 of the casing 41.

[0058] The partition plate 415 divides the inside of the casing 41 into a first chamber S1 and a second chamber S2. The first chamber S1 is an air-blowing chamber, and the second chamber S2 is a machine chamber. The first chamber S1 and the second chamber S2 are each a space defined by the front plate 411, the top plate 412, the bottom plate 413, and the side plates 414 of the casing 41 and the partition plate 415.

[0059] (2-4) Communication Pipe As shown in FIG. 1 , the communication pipe 42 is connected to the refrigerant circuit 20. The communication pipe 42 is, for example, brazed to the piping of the refrigerant circuit 20. In the present embodiment, the communication pipe 42 is connected to the low-pressure side of the refrigerant circuit 20. The low-pressure side is the side of the heat source unit 2 where the pressure of the refrigerant circulating through the refrigerant circuit 20 is relatively low. In FIG. 1 , the communication pipe 42 is connected between the accumulator 27 and the liquid-gas heat exchanger 26 in the refrigerant circuit 20. Because the communication pipe 42 communicates with the refrigerant piping that constitutes the refrigerant circuit 20, refrigerant containing refrigerating machine oil circulating through the refrigerant circuit 20 may flow into the communication pipe 42.

[0060] The connecting pipe 42 is a metal pipe. As shown in Figures 3 and 4, the connecting pipe 42 has a capillary 421, a first connecting pipe 422, and a second connecting pipe 423. The capillary 421, the first connecting pipe 422, and the second connecting pipe 423 are in communication with each other. The outer diameters of the first connecting pipe 422 and the second connecting pipe 423 are larger than the outer diameter of the capillary 421. Here, the first connecting pipe 422 is connected to the refrigerant circuit 20. The second connecting pipe 423 is connected to the connection portion 43. The capillary 421 connects the first connecting pipe 422 and the second connecting pipe 423.

[0061] 1, 4, and 5, the connection part 43 is connected to the refrigerant container 44. In this embodiment, the connection part 43 connects the communication pipe 42 and the refrigerant container 44. Here, the connection part 43 communicates with the communication pipe 42 and the refrigerant container 44.

[0062] 3 to 5 , the connection part 43 has a connection valve 431 and a connection pipe 432. The connection valve 431 is a shut-off valve that opens and closes the connection pipe 42. When the connection valve 431 is opened, the connection part 43 is connected to the refrigerant circuit 20 via the connection pipe 42, and when the connection valve 431 is closed, the connection part 43 is cut off from the refrigerant circuit 20. A second connection pipe 423 and a connection pipe 432 are connected to the connection valve 431. The connection pipe 432 is connected to the refrigerant container 44. The connection pipe 432 has approximately the same inner diameter as the first connection pipe 422 and the second connection pipe 423.

[0063] (2-6) Refrigerant Container The refrigerant container 44 is filled with a flammable refrigerant. In other words, the refrigerant container 44 is configured to be able to be filled with a flammable refrigerant. The refrigerant container 44 is a container that supplies the flammable refrigerant to the refrigerant circuit 20. Therefore, the flammable refrigerant filled in the refrigerant container 44 is supplied to the refrigerant circuit 20. Therefore, after the flammable refrigerant in the refrigerant container 44 is supplied to the refrigerant circuit 20, the refrigerant container 44 is not filled with the flammable refrigerant. In other words, the heat source unit 2 has a case where the refrigerant container 44 is filled with a flammable refrigerant and a case where the refrigerant container 44 is not filled with the flammable refrigerant.

[0064] 2 and 5 , the refrigerant container 44 is supported by the bottom plate 413 of the casing 41. In other words, the refrigerant container 44 is disposed so that a load is applied to the bottom plate 413. In this embodiment, the refrigerant container 44 is fixed to the bottom plate 413 of the casing 41 via a protective member 46 and a base 47.

[0065] 1 , the refrigerant container 44 is connected to the refrigerant circuit 20. In the present embodiment, the refrigerant container 44 is connected to the refrigerant circuit 20 via a connection portion 43 and a communication pipe 42. Here, the refrigerant container 44 is connected to the connection portion 43.

[0066] 4 and 5 , the connection portion 43 is provided at the bottom of the refrigerant container 44. In other words, the refrigerant discharge portion of the refrigerant container 44 is located below the refrigerant container 44. In other words, the refrigerant container 44 is placed upside down (upside down). Therefore, when the refrigerant filled in the refrigerant container 44 is supplied to the refrigerant circuit 20, the refrigerant filled inside the refrigerant container 44 flows from the bottom of the refrigerant container 44 to the refrigerant circuit 20.

[0067] The refrigerant container 44 is made of metal. The refrigerant container 44 has a generally cylindrical shape. Specifically, as shown in FIG. 4 , the refrigerant container 44 includes a cylindrical portion 441, an upper portion 442, and a lower portion 443. The cylindrical portion 441 extends in the vertical direction. The outer diameter of the upper portion 442 is smaller than the outer diameter of the cylindrical portion 441. The upper portion 442 is continuous with the upper end of the cylindrical portion 441. The upper portion 442 has a lid portion located at the upper end. The outer diameter of the lower portion 443 is smaller than the outer diameter of the cylindrical portion 441. The lower portion 443 is continuous with the lower end of the cylindrical portion 441.

[0068] (2-7) Buffer Material As shown in FIGS. 3 to 5, the buffer material 45 is attached to the refrigerant container 44. In FIGS. 3 and 4, the buffer material 45 includes a first buffer material 451 that covers the cylindrical portion 441 and a second buffer material 452 that covers the upper portion 442. The first buffer material 451 is a sheet-like or cylindrical member wrapped around the cylindrical portion 441. The sheet-like member may be one sheet or multiple sheets. The buffer material 45 is made of an elastic material such as rubber, for example.

[0069] (2-8) Protective Member As shown in Figures 2, 3, and 5, the protective member 46 is disposed below the refrigerant container 44. The protective member 46 is fixed to the refrigerant container 44. Here, the protective member 46 is integrated with the refrigerant container 44. In particular, the protective member 46 is integrated with the refrigerant container 44 by welding, and cannot be attached to or detached from the refrigerant container 44.

[0070] 3 and 5 , the protective member 46 protects the connection portion 43. The protective member 46 protects at least the connection valve 431. Here, the protective member 46 protects the connection portion 43 from the connection valve 431 to the refrigerant container 44.

[0071] In FIG. 3 , the protective member 46 covers the connection portion 43 at a distance from the connection portion 43. Specifically, the protective member 46 is cylindrical. The protective member 46 may surround the entire periphery of the connection portion 43, but in this example, the protective member 46 has an opening 461. The opening 461 is provided on the maintenance side. The maintenance side is, for example, the front plate 411 side or the side plate 414 side, and in FIGS. 3 and 5 , the opening 461 is located on the front plate 411 side. As shown in FIG. 3 , a second communication pipe 423 connected to the connection valve 431 passes through the opening 461.

[0072] The protective member 46 is made of, for example, metal and has a thickness of preferably 2 mm to 10 mm, more preferably 3 mm to 6 mm.

[0073] (2-9) Pedestal As shown in Figures 2 to 5, the pedestal 47 is provided below the refrigerant container 44 and the protective member 46. The pedestal 47 contacts the protective member 46. Here, the pedestal 47 is fixed to the protective member 46. In Figure 3, the pedestal 47 is fixed to the protective member 46 with bolts B.

[0074] The base 47 is disposed on the bottom plate 413 of the casing 41. Here, the base 47 is fixed to the bottom plate 413.

[0075] The base 47 has an elastic member 471, a support base 472, and a connecting member 473. The elastic member 471 contacts the bottom plate 413. The elastic member 471 is made of, for example, rubber. The connecting member 473 is disposed on the elastic member 471. The connecting member 473 connects the elastic member 471 and the support base 472. The support base 472 is disposed on the connecting member 473. The support base 472 is fixed to the protection member 46. The support base 472 and the connecting member 473 are made of, for example, metal.

[0076] (2-10) Control Unit The control unit 4 shown in Fig. 1 controls the components of the heat source unit 2. The control unit 4 is configured by communicatively connecting the compressor 21, four-way switching valve 22, pressure reducing valve 24, gas injection valve 28, solenoid valve 32, etc.

[0077] The control unit 4 is realized by a computer. The control unit 4 includes a control and arithmetic unit and a storage device. The control and arithmetic unit can be a processor such as a CPU or a GPU. The control and arithmetic unit reads a program stored in the storage device and performs predetermined image processing and arithmetic processing in accordance with the program. Furthermore, the control and arithmetic unit can write the results of calculations to the storage device and read information stored in the storage device in accordance with the program.

[0078] (3) User Machine The user machine 3 is installed inside the building. The heat source machine 2 and the user machine 3 are thermally connected via the second heat exchanger 25. Here, the water circuit 30 of the user machine 3 is connected to the water flow path that flows inside the second heat exchanger 25.

[0079] (4) Operation The operation of the refrigeration cycle apparatus 1 will be described with reference to Fig. 1. The refrigeration cycle apparatus 1 is capable of performing a cooling operation to cool indoor air and a heating operation to heat indoor air for indoor air conditioning. In the cooling operation and the heating operation, the operation of the refrigeration cycle apparatus 1 is controlled by the control unit 4.

[0080] In FIG. 1, the dashed arrows indicate the flow of refrigerant in the refrigerant circuit 20 during heating operation, and the solid arrows indicate the flow of refrigerant in the refrigerant circuit 20 during cooling operation.

[0081] (4-1) Heating Operation During heating operation, the control unit 4 switches the flow path of the four-way switching valve 22 as shown by the dotted lines in FIG. 1, and circulates the refrigerant through the compressor 21, the second heat exchanger 25, the pressure reducing valve 24, and the first heat exchanger 23 in that order.

[0082] The refrigerant compressed to a high temperature and high pressure by the compressor 21 becomes a high-temperature gas refrigerant, flows out from the discharge port 21c, and flows into the second heat exchanger 25. In the second heat exchanger 25, the high-temperature gas refrigerant heats the water in the water circuit 30, and the refrigerant is liquefied. The water that has exchanged heat with the refrigerant circulates through the water circuit 30 and heats the air in the target space.

[0083] The control unit 4 monitors the temperature of the refrigerant coming out of the discharge port 21c of the compressor 21 via the temperature sensor 50, and when the temperature exceeds a predetermined value, the control unit 4 opens the gas injection valve 28.

[0084] The liquid refrigerant flowing out of the second heat exchanger 25 flows toward the economizer heat exchanger 29 and flows into a first flow path 29a of the economizer heat exchanger 29. Part of the refrigerant flowing into the first flow path 29a branches into a second flow path 29b toward the gas injection valve 28, and the rest branches into a liquid refrigerant flow path 26b of the liquid-gas heat exchanger 26. The refrigerant that flows into the second flow path 29b passes through the gas injection valve 28, becomes a low-temperature gas-liquid two-phase refrigerant, and flows into the economizer heat exchanger 29.

[0085] In the economizer heat exchanger 29, heat is exchanged between the gas-liquid two-phase refrigerant from the gas injection valve 28 and the high-temperature liquid refrigerant flowing through the first flow path 29a. As a result, the gas-liquid two-phase refrigerant is heated and becomes a nearly saturated gas refrigerant, and the liquid refrigerant flowing through the first flow path 29a is subcooled.

[0086] The gas refrigerant flowing out of the economizer heat exchanger 29 flows into the inlet 21b of the compressor 21. The inlet 21b of the compressor 21 is located in the middle of the compression stage of the compressor 21. Therefore, the gas refrigerant flowing in through the inlet 21b enters a section where the refrigerant from the suction port 21a has already been partially compressed.

[0087] The refrigerant flowing through the liquid refrigerant flow path 26b of the liquid-gas heat exchanger 26 flows toward the pressure reducing valve 24. The refrigerant that flows into the pressure reducing valve 24 expands in the pressure reducing valve 24 and becomes a low-temperature gas-liquid two-phase refrigerant. This refrigerant flows into the first heat exchanger 23 and evaporates in the first heat exchanger 23.

[0088] The refrigerant flowing out from the first heat exchanger 23 flows through the gas refrigerant flow path 26a of the liquid-gas heat exchanger 26 toward the accumulator 27. The refrigerant that flows into the accumulator 27 has excess liquid components recovered in the accumulator 27.

[0089] In the liquid-gas heat exchanger 26, heat is exchanged between the liquid refrigerant flowing toward the pressure reducing valve 24 and the gas refrigerant flowing out of the first heat exchanger 23, so that the refrigerant flowing toward the pressure reducing valve 24 is supercooled.

[0090] The gas refrigerant that flows out of the accumulator 27 returns to the suction port 21a of the compressor 21. Thereafter, the gas refrigerant is compressed by the compressor 21 to a high temperature and high pressure.

[0091] (4-2) Cooling Operation During cooling operation, the control unit 4 switches the flow path of the four-way switching valve 22 as shown by the solid lines in FIG. 1, and circulates the refrigerant through the compressor 21, the first heat exchanger 23, the pressure reducing valve 24, and the second heat exchanger 25 in that order.

[0092] The refrigerant compressed to a high temperature and high pressure by the compressor 21 becomes a high-temperature gas refrigerant, flows out from the discharge port 21c, and flows into the first heat exchanger 23. In the first heat exchanger 23, the high-temperature gas refrigerant exchanges heat with outside air, and the refrigerant is liquefied.

[0093] The liquid refrigerant flowing out of the first heat exchanger 23 expands in the pressure reducing valve 24 to become a low-temperature gas-liquid two-phase refrigerant. This refrigerant flows into the second heat exchanger 25 via the refrigerant flow path 31. During cooling operation, the solenoid valve 32 is closed, so the refrigerant flowing through the refrigerant flow path 31 does not flow into the economizer heat exchanger 29.

[0094] The refrigerant that has flowed into the second heat exchanger 25 exchanges heat with the water flowing through the water circuit 30 in the second heat exchanger 25, evaporating and cooling the water. The water that has exchanged heat with the refrigerant circulates through the water circuit 30 and cools the air in the target space.

[0095] The gas refrigerant flowing out from the second heat exchanger 25 flows through the gas refrigerant flow path 26a of the liquid-gas heat exchanger 26 toward the accumulator 27. The refrigerant that flows into the accumulator 27 has excess liquid components recovered in the accumulator 27.

[0096] The gas refrigerant that flows out of the accumulator 27 returns to the suction port 21a of the compressor 21. Thereafter, the gas refrigerant is compressed by the compressor 21 to a high temperature and high pressure.

[0097] (5) Refrigerant Charging Method A method for charging a flammable refrigerant into the refrigerant circuit 20 of the heat source unit 2 will be described with reference to FIGS. 1 to 5. FIG.

[0098] First, a heat source unit 2 is prepared, which includes a refrigerant circuit 20, a communication pipe 42 connected to the refrigerant circuit 20, a connection part 43 connected to the communication pipe 42, a refrigerant container 44 connected to the connection part 43, a buffer material 45 attached to the refrigerant container 44, a protective member 46 that protects the connection part 43, and a base 47 fixed to the protective member 46. A small amount of flammable refrigerant is sealed in the refrigerant circuit 20. The refrigerant container 44 is filled with the flammable refrigerant. The heat source unit 2 is then transported to the installation location (on-site).

[0099] The heat source unit 2 is installed on-site. Then, the connection valve 431 is opened, and the refrigerant filled in the refrigerant container 44 is caused to flow into the refrigerant circuit 20 through the connection part 43 and the communication pipe 42. This allows the flammable refrigerant filled in the refrigerant container 44 to be supplied to the refrigerant circuit 20. In this way, in this embodiment, the flammable refrigerant is sealed in the refrigerant circuit 20 when the heat source unit 2 is installed.

[0100] (6) Features (6-1) The heat source unit 2 of this embodiment includes a refrigerant circuit 20, a refrigerant container 44, a connection portion 43, a communication pipe 42, and a protective member 46. The refrigerant circuit 20 includes a compressor 21 and a first heat exchanger 23. The refrigerant container 44 is connected to the refrigerant circuit 20. The refrigerant container 44 is filled with a flammable refrigerant. The connection portion 43 is connected to the refrigerant container 44. The communication pipe 42 connects the connection portion 43 and the refrigerant circuit 20. The protective member 46 protects the connection portion 43.

[0101] According to the heat source unit 2 of this embodiment, the connection portion 43 connected to the refrigerant container 44 filled with a flammable refrigerant is protected by the protective member 46. This makes it possible to prevent damage to the connection portion 43 during installation of the heat source unit 2 including the refrigerant container 44 filled with a flammable refrigerant. This improves the safety of the heat source unit 2 that uses a flammable refrigerant.

[0102] (6-2) In the heat source unit 2 of this embodiment, the connection portion 43 preferably has a connection valve 431 that opens and closes the communication pipe 42. The protection member 46 protects the connection valve 431.

[0103] Here, the protective member 46 can protect the connection valve 431 that opens and closes the communication pipe 42 connected to the refrigerant circuit 20, thereby further improving safety.

[0104] (6-3) In the heat source unit 2 of this embodiment, the protective member 46 preferably has an opening 461 .

[0105] Here, work can be performed through the opening 461 of the protective member 46, improving workability.

[0106] (6-4) In the heat source unit 2 of this embodiment, the opening 461 is preferably provided on the maintenance side.

[0107] Here, the opening 461 of the protective member 46 is provided on the maintenance side, so that an operator can easily perform maintenance on the connection parts 43 such as the connection valve 431 through the opening 461 by removing the maintenance side plate (e.g., the front plate 411) of the casing 41.

[0108] (6-5) In the heat source unit 2 of this embodiment, the connection portion 43 is preferably provided at the bottom of the refrigerant container 44 .

[0109] Here, the connecting portion 43 is provided at the bottom of the refrigerant container 44, and therefore the refrigerant container 44 is fixed to the bottom plate 413 of the casing 41 in a manner such that the flammable refrigerant flows from the bottom of the refrigerant container 44 to the refrigerant circuit 20. Therefore, even if refrigerating machine oil flows into the refrigerant container 44 during normal operation such as cooling operation or heating operation after refrigerant is supplied from the refrigerant container 44 to the refrigerant circuit 20, the refrigerating machine oil can be easily discharged because the refrigerant container 44 is placed upside down. This improves the ability to discharge the refrigerating machine oil contained in the refrigerant.

[0110] Furthermore, since the refrigerant container 44 is placed upside down, the length of the connecting pipe 42 can be shortened.

[0111] (6-6) The heat source unit 2 of this embodiment preferably further includes a casing 41 and a base 47. The casing 41 houses the compressor 21, the first heat exchanger 23, the refrigerant container 44, the connection portion 43, the connecting pipe 42, and the protective member 46. The base 47 is disposed on the bottom plate 413 of the casing 41. The base 47 contacts the protective member 46.

[0112] In this manner, the refrigerant container 44 may be fixed to the bottom plate 413 of the casing 41 via the base 47 and the protective member 46 .

[0113] (6-7) In the heat source unit 2 of this embodiment, the base 47 is preferably fixed to the protective member 46 .

[0114] Here, since the base 47 disposed on the bottom plate 413 of the casing 41 and the protective member 46 are fixed, the connecting portion 43 can be more appropriately protected by the protective member 46 .

[0115] (6-8) In the heat source unit 2 of this embodiment, the base 47 preferably has an elastic member 471. The elastic member 471 contacts the bottom plate 413.

[0116] Here, even if the refrigerant container 44 is dropped, the elastic member 471 absorbs the impact of the drop, thereby preventing damage to the refrigerant container 44 .

[0117] (6-9) Preferably, the heat source unit 2 of this embodiment further includes a buffer material 45. The buffer material 45 is attached to the refrigerant container 44.

[0118] Here, even if the refrigerant container 44 is subjected to an impact such as being dropped, the shock absorbing material 45 can absorb the impact and protect the refrigerant container 44 .

[0119] (6-10) In the heat source unit 2 of this embodiment, the communication pipe 42 is preferably connected to the low-pressure side of the refrigerant circuit 20 .

[0120] In this way, the refrigerant container 44 may be connected to the low-pressure side of the refrigerant circuit 20 via the communication pipe 42 and the connection part 43 .

[0121] (6-11) In the heat source unit 2 of this embodiment, the connecting pipe 42 preferably has a capillary 421 .

[0122] Here, even if a load is applied to the connecting pipe 42 from the refrigerant circuit 20 side, the capillary 421 acts as an elastic member, thereby reducing the load applied to the connection part 43 (particularly the connection valve 431).

[0123] (6-12) In the heat source unit 2 of this embodiment, the protective member 46 preferably has a thickness of 2 mm or more and 10 mm or less.

[0124] Here, the thickness of the protective member 46 is 2 mm or more and 10 mm or less, and therefore the protective member 46 is strong. Therefore, the protective member 46 can further prevent damage to the connection portion 43.

[0125] (6-13) In the heat source unit 2 of this embodiment, the protective member 46 is preferably integrated with the refrigerant container 44 .

[0126] Here, it is possible to stably fix the protection member 46 and the refrigerant container 44. Therefore, the protection member 46 can further prevent damage to the connection portion 43.

[0127] (6-14) The refrigeration cycle device 1 of this embodiment includes a heat source unit 2 and a utilization unit 3. The heat source unit 2 is any one of the heat source units 2 described above. The utilization unit 3 is connected to the heat source unit 2.

[0128] According to the refrigeration cycle apparatus 1 of this embodiment, the flammable refrigerant can be filled into the refrigerant circuit 20 from the refrigerant container 44 that is stably arranged, thereby improving safety.

[0129] (7) Modifications (7-1) Modification 1 In the above embodiment, in the second heat exchanger 25, the refrigerant flowing through the refrigerant circuit 20 exchanges heat with the water flowing through the water circuit 30, but this is not limited to this. In this modification, the refrigerant flowing through the refrigerant circuit 20 may exchange heat with the air in the target space. In this case, the water circuit 30 is omitted, and the second heat exchanger 25 is disposed in the target space.

[0130] (7-2) Modification 2 In the above embodiment, the casing 41 accommodates the entire refrigerant circuit 20. However, this is not limitative. In this modification, the casing 41 accommodates only a portion of the refrigerant circuit 20.

[0131] Although the embodiments of the present disclosure have been described above, it will be understood that various changes in form and details can be made without departing from the spirit and scope of the present disclosure as defined in the claims.

[0132] DESCRIPTION OF SYMBOLS 1: Refrigeration cycle device 2: Heat source device 3: User device 20: Refrigerant circuit 21: Compressor 23: First heat exchanger (heat exchanger) 41: Casing 413: Bottom plate 42: Connecting pipe 43: Connection part 431: Connection valve 44: Refrigerant container 45: Cushioning material 46: Protective member 461: Opening 47: Base 471: Elastic member

[0133] Japanese Patent Application Laid-Open No. 2000-28237

Claims

1. a refrigerant circuit (20) including a compressor (21) and a heat exchanger (23); a refrigerant container (44) connected to the refrigerant circuit and filled with a flammable refrigerant; a connection part (43) connected to the refrigerant container; a connecting pipe (42) connecting the connecting portion and the refrigerant circuit; a protective member (46) for protecting the connection portion; A heat source machine (2).

2. The connecting portion has a connecting valve (431) that opens and closes the connecting pipe, The protective member protects the connection valve. The heat source machine according to claim 1.

3. The connection part further has a connection pipe (432) connected to the refrigerant container, The protective member further protects the connecting pipe. The heat source machine according to claim 2.

4. The protective member has an opening (461). The heat source machine according to any one of claims 1 to 3.

5. The opening is provided on the maintenance side. The heat source machine according to claim 4.

6. The connection portion is provided at a lower portion of the refrigerant container. The heat source machine according to any one of claims 1 to 3.

7. a casing (41) that accommodates the compressor, the heat exchanger, the refrigerant container, the connection portion, the connecting pipe, and the protective member; a base (47) disposed on the bottom plate (413) of the casing; Furthermore, The base contacts the protective member. The heat source machine according to claim 6.

8. The base is fixed to the protection member. The heat source machine according to claim 7.

9. The base has an elastic member (471) that contacts the bottom plate. The heat source machine according to claim 7.

10. Further comprising a buffer material (45) attached to the refrigerant container. The heat source machine according to any one of claims 1 to 3.

11. The communication pipe is connected to the low-pressure side of the refrigerant circuit. The heat source machine according to any one of claims 1 to 3.

12. The connecting tube has a capillary (421). The heat source machine according to any one of claims 1 to 3.

13. The protective member has a thickness of 2 mm or more and 10 mm or less. The heat source machine according to any one of claims 1 to 3.

14. The protective member is integral with the refrigerant container. The heat source machine according to any one of claims 1 to 3.

15. The heat source machine according to any one of claims 1 to 3, A utilization machine (3) connected to the heat source machine; A refrigeration cycle device (1) comprising: