Refrigeration cycle device

Abstract

To provide a refrigeration cycle device which can improve system performance while suppressing a disproportionation reaction, by performing injection without an actuation medium containing ethylene fluoroolefin coming into contact with a motor part of a compressor.SOLUTION: A refrigeration cycle device uses an actuation medium containing ethylene fluoroolefin, and includes a compressor, an outdoor heat exchanger, an indoor heat exchanger, and an intermediate pressure receiver. It also includes injection piping for delivering the actuation medium from the intermediate pressure receiver to a compression part in the compressor. The actuation medium injected into the compressor from the injection piping is directly discharged to the outside of the compressor, after being compressed in the compressor.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to a refrigeration cycle device. [Background technology]

[0002] Patent Document 1 discloses a technology in which a means-side compression mechanism and a high-stage side compressor hole are housed and installed within a sealed housing, refrigerant gas compressed by the low-stage side compression mechanism is discharged into the sealed housing, intermediate-pressure refrigerant gas in the sealed housing is sucked into the high-stage side compression mechanism, and injection refrigerant from an injection circuit is discharged into the sealed housing. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2008-144643 A Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure provides a refrigeration cycle device in which a working medium containing an ethylene-based fluoroolefin is injected without coming into contact with a motor section of a compressor, thereby improving system performance while suppressing disproportionation reactions. [Means for solving the problem]

[0005] The refrigeration cycle device of the present disclosure uses a working medium containing an ethylene-based fluoroolefin, and is equipped with a compressor, an outdoor heat exchanger, an indoor heat exchanger, and an oil separator, and is equipped with an injection piping that sends the working medium from the oil separator to a compression section in the compressor, and the working medium injected from the injection piping into the compressor is compressed in the compressor and then directly discharged outside the compressor. Effect of the Invention

[0006] According to the refrigeration cycle device of the present disclosure, the working medium injected from the injection pipe is compressed by the compressor and then directly discharged to the outside of the compressor without being discharged inside the compressor, so that the working medium can be prevented from accumulating in the compressor. Therefore, the ethylene-based fluoroolefin-based working medium can be injected without coming into contact with the motor part of the compressor, so that the system performance can be improved while suppressing the disproportionation reaction. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a schematic diagram showing an overall configuration of a refrigeration cycle device according to a first embodiment. [Diagram 2] FIG. 1 is a schematic diagram showing a compressor according to a first embodiment. [Diagram 3] FIG. 13 is a schematic diagram showing the overall configuration of a refrigeration cycle device according to a second embodiment. [Figure 4] FIG. 11 is a schematic diagram showing a compressor according to a third embodiment. [Diagram 5] FIG. 1 is a schematic diagram of a refrigeration cycle device according to a modified example of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] (The knowledge and other information that formed the basis of this disclosure) At the time when the inventors came up with the idea of ​​the present disclosure, a conventional refrigeration cycle device contained a means-side compression mechanism and a high-stage compression mechanism housed in a sealed housing, and refrigerant gas compressed by the low-stage compression mechanism was discharged into the sealed housing, intermediate-pressure refrigerant gas in the sealed housing was sucked into the high-stage compression mechanism, and injection refrigerant from an injection circuit was discharged into the sealed housing. However, when injection is performed in a refrigeration cycle device using a refrigerant containing a fluorohydrocarbon that has the property of causing a disproportionation reaction, the injected refrigerant is discharged into the compressor sealed housing, and there is a risk of disproportionation reaction occurring if the refrigerant comes into contact with the motor part and a layer short occurs. Therefore, the inventors discovered a problem that the conventional configuration cannot ensure safety by suppressing the disproportionation reaction and improve the system performance by injection at the same time, and have come to configure the subject of the present disclosure in order to solve the problem. Therefore, the present disclosure provides a refrigeration cycle device in which a working medium containing an ethylene-based fluoroolefin is injected without coming into contact with the motor section of the compressor, thereby improving system performance while suppressing disproportionation reactions.

[0009] Hereinafter, the embodiments will be described in detail with reference to the drawings. However, more detailed description than necessary may be omitted. For example, detailed description of already well-known matters or duplicate description of substantially the same configuration may be omitted. It should be noted that the accompanying drawings and the following description are provided to enable those skilled in the art to fully understand the present disclosure, and are not intended to limit the subject matter described in the claims.

[0010] (Embodiment 1) [1-1. Configuration] [1-1-1. Overall configuration of the refrigeration cycle device] FIG. 1 is a schematic diagram showing an overall configuration of a refrigeration cycle device 1 in the first embodiment. As shown in FIG. 1, the refrigeration cycle apparatus 1 includes an outdoor unit 10 and an indoor unit 20. The outdoor unit 10 and the indoor unit 20 are connected via a refrigerant pipe 11 to form a refrigerant circuit through which the refrigerant circulates. The refrigeration cycle device 1 uses a working fluid containing an ethylene-based fluoroolefin in the refrigeration cycle circuit. Many ethylene-based fluoroolefins have a low GWP. On the other hand, it is known that ethylene-based fluoroolefins can cause a disproportionation reaction when exposed to a discharge phenomenon under high temperature and high pressure. The occurrence of a disproportionation reaction can cause a sudden pressure rise in the refrigeration cycle circuit. Details of the working fluid will be described later.

[0011] The outdoor unit 10 includes a compressor 12 , an outdoor heat exchanger 13 , an outdoor expansion valve 14 , and an intermediate pressure receiver 15 . The compressor 12 is, for example, a rotary compressor, which draws in a gaseous working medium, compresses it, and discharges it. The outdoor heat exchanger 13 is, for example, a fin-tube type heat exchanger, and drives an outdoor fan (not shown) to cause the working medium flowing inside to exchange heat with the outside air. The outdoor expansion valve 14 is a valve whose opening degree can be changed, and reduces the pressure of the working medium passing therethrough. The intermediate pressure receiver 15 separates and stores oil in the refrigerant.

[0012] One end of an injection pipe 16 is connected to the intermediate pressure receiver 15. The other end of the injection pipe 16 is connected to the compressor 12, and is configured so that the working medium inside the intermediate pressure receiver 15 can be injected from the injection pipe 16 to the compressor 12. An injection expansion valve 17 is provided in the middle of the injection pipe 16 .

[0013] The indoor unit 20 includes an indoor heat exchanger 21 and an indoor expansion valve 22 . The indoor heat exchanger 21 is, for example, a fin-tube type heat exchanger, and exchanges heat between the working medium flowing inside and the indoor air by driving an indoor fan (not shown). The indoor expansion valve 22 is a valve whose opening and closing and its opening degree can be changed.

[0014] [1-1-2. Compressor configuration] FIG. 2 is a schematic diagram showing the compressor according to the first embodiment. As shown in FIG. 2, the compressor 12 is an internal intermediate pressure type multi-stage compression rotary compressor, and a drive motor 31 is accommodated in the upper part inside a cylindrical casing 30 made of steel plate. A low-pressure side compression mechanism 32 and a high-pressure side compression mechanism 33 driven by a drive motor 31 are housed in the lower interior of the casing 30 . The low-pressure side compression mechanism 32 is provided with a low-pressure side suction port 34 and a low-pressure side discharge port 35, and is configured to compress low-pressure refrigerant to an intermediate pressure. The high-pressure side compression mechanism 33 is provided with a high-pressure side intake port 36 and a high-pressure side discharge port 37, and is configured to compress the intermediate-pressure refrigerant to a high pressure. The inside of the casing 30 is maintained at an intermediate pressure.

[0015] A low-pressure side discharge port 35 of the compressor 12 is connected to a high-pressure side suction port 36 of the compressor 12 via an intermediate pipe 38. A high-pressure side discharge port 37 of the compressor 12 is connected to the outdoor heat exchanger 13 via the refrigerant pipe 11.

[0016] [1-1-3. Working medium] The working medium used in the air conditioner 1 is a working medium containing a fluoroolefin (fluoroalkene) such as an ethylene-based fluoroolefin. The specific type of fluoroolefin is not particularly limited, and may include, for example, fluoroethylenes such as 1,1,2-trifluoroethylene (HFO1123), trans-1,2-difluoroethylene (HFO1132(E)), cis-1,2-difluoroethylene (HFO1132(Z)), 1,1-difluoroethylene (HFO1132a), tetrafluoroethylene (FO1114, TFE), and monofluoroethylene (HFO1141); 1,2,3,3,3-pentafluoropropene (HFO-1225ye), 2,3,3,3-tetrafluoropropene (HFO-1234yf), 1,3,3,3-tetrafluoropropene (HFO-1234ze), 1,2,3,3-tetrafluoropropene (HFO-1234ye), and 3,3,3-trifluoropropene (HFO-1243zf).

[0017] The working medium may contain two or more refrigerant components. That is, it may contain a fluoroolefin selected from the above examples (e.g., 1,1,2-trifluoroethylene) and a second refrigerant component. The second refrigerant component may be, but is not limited to, a hydrofluorocarbon (HFC), a hydrofluoroolefin (HFO), a saturated hydrocarbon, carbon dioxide, or other refrigerant.

[0018] Examples of the hydrofluorocarbon include fluoromethanes such as difluoromethane (R32) and trifluoromethane (R23), fluoroethane (R161), 1,1-difluoroethane (R152a), 1,1,1-trifluoroethane (R143a), 1,1,2,2-tetrafluoroethane (R134), 1,1,1,2-tetrafluoroethane (R134a), pentafluoroethane (R125), fluoroethanes such as difluoroethane and trifluoroethane, and 1,1,1,3,3-pentafluoropropane ( fluoropropanes such as 1,1,1,2,3,3-hexafluoropropane (R236ea), 1,1,1,3,3,3-hexafluoropropane (R236fa), and 1,1,1,2,3,3,3-heptafluoropropane (R227ea); fluorobutanes such as 1,1,1,3,3-pentafluorobutane (R365mfc); and fluoropentanes such as 1,1,1,2,3,4,4,5,5,5-decafluoropentane (R4310mee) and heptafluorocyclopentane (Rc447ef).

[0019] Examples of saturated hydrocarbons include ethane, n-propane, cyclopropane, n-butane, cyclobutane, isobutane (2-methylpropane), methylcyclopropane, n-pentane, isopentane (2-methylbutane), neopentane (2,2-dimethylpropane), and methylcyclobutane, but may be other hydrocarbons. The second refrigerant component may include a plurality of components. That is, the second refrigerant component may include two or more refrigerant components selected from hydrofluorocarbons, hydrofluoroolefins, saturated hydrocarbons, carbon dioxide, and other refrigerants.

[0020] The working medium described above may be a refrigerant classified as mildly flammable (A2L), flammable (A2), or highly flammable (A3) according to ISO817.

[0021] [1-1-4. Disproportionation inhibitor] The working medium used as a refrigerant in the air conditioner 1 may contain a disproportionation inhibitor in addition to the refrigerant components. The disproportionation inhibitor is, for example, a saturated hydrocarbon. The working medium may contain a disproportionation inhibitor consisting of one or more components. Saturated hydrocarbons used as disproportionation inhibitors include ethane, n-propane, cyclopropane, n-butane, cyclobutane, isobutane (2-methylpropane), methylcyclopropane, n-pentane, isopentane (2-methylbutane), neopentane (2,2-dimethylpropane), and methylcyclobutane, but may also be other saturated hydrocarbons. A particularly preferred disproportionation inhibitor is n-propane.

[0022] The disproportionation inhibitor may be, for example, a haloalkane having any one to four carbon atoms. The haloalkane used as the disproportionation inhibitor may have any of 1 to 4 carbon atoms, excluding cases where all of the halogen atoms are fluorine. More specifically, examples of the haloalkane include halomethane (halogenated methane) having one carbon atom, haloethane (halogenated ethane) having two carbon atoms, halopropane (halogenated propane) having three carbon atoms, and halobutane (halogenated butane) having four carbon atoms.

[0023] Specifically, the disproportionation-inhibiting haloalkane may be one having the structure of formula (1) shown below. CpHqXr (1)

[0024] In the formula (1), X is a halogen atom selected from the group consisting of fluorine (F), chlorine (Cl), bromine (Br), and iodine (I). p is an integer of either 1 or 2. q is an integer of 0 or greater. r is an integer of 1 or greater. The sum of q and r is 2p+2. When r is 2 or greater, X is the same or different halogen atom.

[0025] However, the disproportionation-inhibited haloalkanes shown in formula (1) above do not include those in which X is composed only of F. This is because disproportionation-inhibited haloalkanes in which X is composed only of F are compounds that can be used in combination with other refrigerant components and do not substantially function as disproportionation inhibitors.

[0026] In the disproportionation-inhibited haloalkane represented by formula (1), the halogen atom X may be at least one of F, Cl, Br, and I, as described above, but is preferably at least I. When the number of carbon atoms is 2 (p=2) and the number of halogen atoms is 2 or more (r≧2), the halogen atom X is preferably at least F and I.

[0027] The disproportionation-inhibiting haloalkane shown in formula (1) is not particularly limited, and specific examples thereof include (mono)iodomethane (CH3I), diiodomethane (CH2I2), dibromomethane (CH2Br2), bromomethane (CH3Br), dichloromethane (CH2Cl2), chloroiodomethane (CH2ClI), dibromochloromethane (CHBr2Cl), tetraiodomethane (CI4), carbon tetrabromide (CBr4), bromotrichloromethane (CBrCl3), dibromodichloromethane (CBr2Cl2), tribromofluoromethane (CBr3F), fluorodiiodomethane (CHFI), and the like. ), difluorodiiodomethane (CF2I2), dibromodifluoromethane (CBr2F2), trifluoroiodomethane (CF3I), and other halomethanes; 1,1,1-trifluoro-2-iodoethane (CF3CH2I), monoiodoethane (CH3CH2I), monobromoethane (CH3CH2Br), 1,1,1-triiodoethane (CH3CI3), 1-bromo-2-iodotetrafluoroethane (CF2BrCF2I), and other halomethanes.

[0028] The working fluid may contain a plurality of disproportionation inhibitors selected from the above-mentioned saturated hydrocarbons and the above-mentioned haloalkanes. The working fluid may contain one type of saturated hydrocarbon, or may be a working fluid containing two or more types of saturated hydrocarbons. The working fluid may contain one type of haloalkane, or may be a working fluid containing two or more types of haloalkanes.

[0029] A preferred example of the working medium is a mixture containing 1,1,2-trifluoroethylene and n-propane. This working medium may contain the second refrigerant component described above, or may contain other components.

[0030] Each of the above working fluids may contain inevitable impurities, such as various additives including stabilizers added for the purpose of stabilization during transportation or storage, residues or by-products of the raw materials for synthesizing the refrigerant components, and substances mixed in for other reasons.

[0031] The mass ratio of 1,1,2-trifluoroethylene and n-propane contained in the working fluid can be appropriately changed. Thus, in the mixed refrigerant, there are no particular limitations on the content (content) of the fluoroolefin or other refrigerants, or the content (content) of the disproportionation inhibitor. For example, when the total amount of the mixed refrigerant is taken as 100% by mass, the fluoroolefin content may be 50% by mass or more, 60% by mass or more, 70% by mass or more, or 80% by mass or more. Furthermore, when the total amount of the mixed refrigerant is taken as 100% by mass, the propane content may be less than 50% by mass, and may be 40% by mass or less, 30% by mass or less, or 20% by mass or less.

[0032] [1-2. Operation] Next, the operation of the first embodiment will be described. In this embodiment, the compressor 12 is driven to compress the working medium and discharge it toward the outdoor heat exchanger 13 . The high-temperature, high-pressure working medium compressed by the compressor 12 exchanges heat with outside air in the outdoor heat exchanger 13 and is condensed, and then expanded by the outdoor expansion valve 14. The working medium is then sent to the indoor expansion valve 22 via the intermediate pressure receiver 15, where it is further expanded and sent to the indoor heat exchanger 21. The working medium exchanges heat with the indoor air by the indoor heat exchanger 21 to cool the indoor air, and then is returned to the compressor 12. Through this series of operations, the room can be cooled.

[0033] In this case, by opening the injection expansion valve 17 of the injection pipe 16 , the working medium stored in the intermediate pressure receiver 15 is sent to the high pressure side suction port 36 of the compressor 12 via the injection pipe 16 . The working medium sent from the injection pipe 16 to the high-pressure side suction port 36 of the compressor 12 is compressed by the high-pressure side compression mechanism 33 and then discharged towards the outdoor heat exchanger 13 . That is, the working medium sent from the injection pipe 16 is discharged to the outside of the compressor 12 without being discharged into the casing 30 in an intermediate pressure state. As a result, after the working medium injected from the injection pipe 16 is compressed by the high-pressure side compression mechanism 33, it is discharged directly to the outside of the compressor 12 without being discharged inside the compressor 12, thereby preventing the working medium from stagnating inside the compressor 12.

[0034] [1-3. Effects, etc.] As described above, the refrigeration cycle device 1 of this embodiment uses a working medium containing an ethylene-based fluoroolefin, and is equipped with a compressor 12, an outdoor heat exchanger 13, an indoor heat exchanger, and an intermediate pressure receiver 15. The refrigeration cycle device 1 uses an ethylene-based fluoroolefin-containing working medium, and is equipped with an injection pipe 16 that sends the working medium from the intermediate pressure receiver 15 to a compression section in the compressor 12. The working medium injected from the injection pipe 16 into the compressor 12 is compressed in the compressor 12 and then directly discharged outside the compressor 12. As a result, after the working medium injected from the injection pipe 16 is compressed by the compressor 12, it is not discharged into the compressor 12 but is directly discharged to the outside of the compressor 12, so that it is possible to prevent the working medium from accumulating in the compressor 12. Therefore, the ethylene-based fluoroolefin-based working medium can be injected without coming into contact with the motor part of the compressor 12, so that it is possible to improve the system performance while suppressing the disproportionation reaction.

[0035] In addition, in the refrigeration cycle device 1 of this embodiment, the compressor 12 is equipped with a two-stage compression mechanism having a low-pressure side and a high-pressure side, and an injection pipe 16 is connected to an intake pipe that draws the working medium discharged from the low-pressure side compression mechanism into the high-pressure side compression mechanism. As a result, after the working medium injected from the injection pipe 16 is compressed by the compressor 12, it is not discharged into the compressor 12 but is directly discharged to the outside of the compressor 12, so that it is possible to prevent the working medium from accumulating in the compressor 12. Therefore, the ethylene-based fluoroolefin-based working medium can be injected without coming into contact with the motor part of the compressor 12, so that it is possible to improve the system performance while suppressing the disproportionation reaction.

[0036] (Embodiment 2) Next, a second embodiment of the present disclosure will be described. [2-3. Configuration] FIG. 3 is a schematic diagram showing an overall configuration of a refrigeration cycle device 1 in the second embodiment. As shown in FIG. 3, in this embodiment, the compressor 12 is configured with two compressors 12, that is, a low-pressure side compressor 12a and a high-pressure side compressor 12b. The low-pressure side compressor 12a is provided with a low-pressure side suction port 34 and a low-pressure side discharge port 35, and the high-pressure side compressor 12b is provided with a high-pressure side suction port 36 and a high-pressure side discharge port 37. A low-pressure side discharge port 35 of the low-pressure side compressor 12a and a high-pressure side suction port 36 of the high-pressure side compressor 12b are connected via an intermediate pipe 38. The intermediate pipe 38 is connected to the injection pipe 16 .

[0037] [2-2. Operation] Next, the operation of the second embodiment will be described. In this embodiment, as in embodiment 1, the working medium sent from the injection pipe 16 to the high-pressure side intake port 36 of the high-pressure side compressor 12b is compressed by the high-pressure side compressor 12b and then discharged toward the indoor heat exchanger 21. As a result, the working medium injected from the injection pipe 16 is compressed by the high-pressure side compressor 12b and then discharged directly to the outside of the high-pressure side compressor 12b, thereby preventing the working medium from stagnating within the compressor 12.

[0038] [2-3. Effects, etc.] As described above, in the refrigeration cycle device 1 of this embodiment, the compressor 12 is composed of a low-pressure side compressor 12a and a high-pressure side compressor 12b, and the injection pipe 16 is connected to the intermediate pipe 38 that draws the working medium discharged from the low-pressure side compressor 12a into the high-pressure side compressor 12b. As a result, after the working medium injected from the injection pipe 16 is compressed by the high-pressure side compressor 12b, it is not discharged into the high-pressure side compressor 12b but is directly discharged to the outside of the high-pressure side compressor 12b, which makes it possible to prevent the working medium from accumulating in the compressor 12. Therefore, the ethylene-based fluoroolefin-based working medium can be injected without coming into contact with the motor part of the compressor 12, making it possible to improve system performance while suppressing the disproportionation reaction.

[0039] (Embodiment 3) Next, a third embodiment of the present disclosure will be described. FIG. 4 is a schematic diagram showing a compressor according to the third embodiment. As shown in FIG. 4, the injection pipe 16 is connected to an intermediate pipe 38 that connects the low-pressure side compression mechanism 32 and the high-pressure side compression mechanism 33 of the compressor 12. In this embodiment, a mixer 40 is provided at the connection between the intermediate pipe 38 and the injection pipe 16. The mixer 40 mixes the working medium sent from the intermediate pipe 38 and the working medium sent from the injection pipe 16, and homogenizes the concentrations of the working mediums. The other configurations are the same as those in the first embodiment, so the same parts are given the same reference numerals and the description thereof is omitted.

[0040] [3-2. Operation] Next, the operation of the third embodiment will be described. In this embodiment, by opening the injection expansion valve 17 of the injection pipe 16, the working medium stored in the intermediate pressure receiver 15 is sent to the high pressure side suction port 36 of the compressor 12 via the injection pipe 16. At this time, the working medium sent from the injection pipe 16 is mixed with the working medium sent from the intermediate pipe 38 in the mixer 40, and the working medium with a uniform concentration is sent to the high-pressure side compression mechanism 33. This makes it possible to prevent the working medium from becoming locally concentrated. The working medium sent from the mixer 40 to the high-pressure side suction port 36 of the compressor 12 is compressed by the high-pressure side compression mechanism 33 and then discharged towards the outdoor heat exchanger 13 . That is, the working medium sent from the injection pipe 16 is discharged to the outside of the compressor 12 without being discharged into the casing 30 in an intermediate pressure state. As a result, after the working medium injected from the injection pipe 16 is compressed by the high-pressure side compression mechanism 33, it is discharged directly to the outside of the compressor 12 without being discharged inside the compressor 12, thereby preventing the working medium from stagnating inside the compressor 12.

[0041] [3-3. Effects, etc.] As described above, the refrigeration cycle device 1 of this embodiment is equipped with a mixing section 40 that mixes the working medium inside the compressor 12 with the working medium injected from the intermediate pressure receiver 15, and the working medium discharged from the mixing section 40 is sucked into the compression section of the compressor 12. As a result, the working medium sent from the injection pipe 16 and the working medium sent from the intermediate pipe 38 are mixed in the mixer 40, and the working medium is sent to the high-pressure side compression mechanism 33 in a state where the concentration of the working medium is made uniform, so that it is possible to prevent the working medium from becoming locally highly concentrated. Therefore, even if the ethylene-based fluoroolefin-based working medium comes into contact with the motor part of the compressor 12, the concentration can be kept low, so that the system performance can be improved while suppressing the disproportionation reaction.

[0042] (Modification) FIG. 5 is a schematic diagram of a refrigeration cycle device 1 showing a modified example of the present disclosure. As shown in FIG. 5, the compressor 12 is composed of two compressors 12, a low-pressure side compressor 12a and a high-pressure side compressor 12b, and the injection pipe 16 is connected to an intermediate pipe 38 that connects the low-pressure side compressor 12a and the high-pressure side compressor 12b. A mixing section 40 is provided at the connection between the intermediate pipe 38 and the injection pipe 16 . By configuring in this way, it is possible to obtain the same functions and effects as those of the above-described embodiment.

[0043] (Other embodiments) As described above, the first to third embodiments have been described as examples of the technology disclosed in this application. However, the technology in this disclosure is not limited to these, and can be applied to embodiments in which modifications, substitutions, additions, omissions, etc. are made. In addition, it is also possible to combine the components described in the first to third embodiments to create new embodiments.

[0044] For example, an oil separator may be provided between the compressor 12 and the exterior heat exchanger 13, and the oil separated by the oil separator may be returned to the compressor 12. In this case, the amount of oil discharged increases as the working medium is discharged directly from the compressor 12 to the outside of the compressor 12. The large amount of oil discharged to the outside of the compressor 12 can be recovered by an oil separator and returned to the compressor 12. This allows the oil to be reliably supplied to the sliding parts of the compressor 12 and prevents the oil from stagnating inside the refrigeration cycle device 1, thereby further improving system performance while reliably suppressing the disproportionation reaction.

[0045] [Configuration supported by the above embodiment] The above embodiment supports the following configurations.

[0046] (Additional Note) (Technology 1) A refrigeration cycle device that uses a working medium containing an ethylene-based fluoroolefin, and that is equipped with a compressor, an outdoor heat exchanger, an indoor heat exchanger, and an intermediate pressure receiver, and that is equipped with an injection pipe that sends the working medium from the intermediate pressure receiver to a compression section in the compressor, and the working medium injected from the injection pipe to the compressor is compressed in the compressor and then directly discharged to the outside of the compressor. According to this configuration, the working medium injected from the injection pipe is compressed by the compressor and then directly discharged to the outside of the compressor without being discharged inside the compressor, so that the working medium can be prevented from accumulating in the compressor. Therefore, the ethylene-based fluoroolefin-based working medium can be injected without coming into contact with the motor part of the compressor, so that the system performance can be improved while suppressing the disproportionation reaction.

[0047] (Technical 2) The refrigeration cycle device according to Technical 1, wherein the compressor is provided with a two-stage compression mechanism having a low pressure side and a high pressure side, and the injection pipe is connected to a suction pipe that draws the working medium discharged from the low pressure side compression mechanism into the high pressure side compression mechanism. According to this configuration, the working medium injected from the injection pipe is compressed by the compressor and then directly discharged to the outside of the compressor without being discharged inside the compressor, so that the working medium can be prevented from accumulating in the compressor. Therefore, the ethylene-based fluoroolefin-based working medium can be injected without coming into contact with the motor part of the compressor, so that the system performance can be improved while suppressing the disproportionation reaction.

[0048] (Technology 3) The refrigeration cycle apparatus according to Technology 2, further comprising a mixing section that mixes the working medium inside the compressor with the working medium injected from the intermediate pressure receiver, and the working medium discharged from the mixing section is sucked into a compression section of the compressor. According to this configuration, the working medium sent from the injection pipe and the working medium sent from the intermediate pipe are mixed in the mixing section, and the working medium is sent to the high-pressure compression mechanism in a state where the concentration of the working medium is made uniform, so that it is possible to prevent the working medium from becoming locally highly concentrated. Therefore, even if the ethylene-based fluoroolefin-based working medium comes into contact with the motor section of the compressor, the concentration can be kept low, so that the system performance can be improved while suppressing the disproportionation reaction.

[0049] (Technology 4) The refrigeration cycle device according to any one of Technology 1 to Technology 3, wherein the working medium is a mixture of a plurality of working mediums, and includes at least a working medium having a boiling point higher than that of the ethylene-based fluoroolefin. According to this configuration, the ethylene-based fluoroolefins having a low boiling point are easily separated as a gas in the intermediate pressure receiver, and the separated ethylene-based fluoroolefins are injected into the compressor. This prevents the ethylene-based fluoroolefins, which may cause a disproportionation reaction, from flowing into the compressor. Therefore, the system performance can be improved while reliably suppressing the disproportionation reaction.

[0050] (Technical 5) The refrigeration cycle device according to any one of Technical 1 to Technical 4, wherein an oil separator is provided between the compressor and the outdoor heat exchanger, and oil separated by the oil separator is returned to the compressor. According to this configuration, a large amount of oil discharged to the outside of the compressor can be recovered by the oil separator and returned to the compressor. Therefore, the oil can be reliably supplied to the sliding parts of the compressor, and the oil does not remain inside the refrigeration cycle device 1. Therefore, the disproportionation reaction can be reliably suppressed and the system performance can be further improved. [Industrial Applicability]

[0051] INDUSTRIAL APPLICABILITY The present disclosure is preferably applicable to a refrigeration cycle device in which a working medium containing an ethylene-based fluoroolefin is injected without coming into contact with the motor section of a compressor, thereby improving system performance while suppressing disproportionation reactions. [Explanation of symbols]

[0052] 1 Refrigeration cycle equipment 10 Outdoor unit 11 Refrigerant piping 12 Compressor 12a Low pressure side compressor 12b High pressure compressor 13 Outdoor heat exchanger 14 Outdoor expansion valve 15 Intermediate pressure receiver 16 Injection piping 17 Injection expansion valve 20 Indoor unit 21 Indoor heat exchanger 22 Indoor expansion valve 30 Casing 31 Drive motor 32 Low pressure side compression mechanism 33 High pressure side compression mechanism 34 Low pressure side intake port 35 Low pressure side outlet 36 High pressure intake port 37 High pressure side outlet 38 Intermediate piping 40 Mixing section

Claims

1. The system uses a working fluid containing an ethylene-based fluoroolefin, and is equipped with a compressor, an outdoor heat exchanger, an indoor heat exchanger, and an intermediate pressure receiver; an injection pipe that sends the working medium from the intermediate pressure receiver to a compression section in the compressor; The working medium injected from the injection pipe into the compressor is compressed by the compressor and then directly discharged to the outside of the compressor. Refrigeration cycle equipment.

2. The compressor is provided with a two-stage compression mechanism having a low pressure side and a high pressure side, The injection pipe is connected to a suction pipe that draws the working medium discharged from the low-pressure side compression mechanism into the high-pressure side compression mechanism. The refrigeration cycle device according to claim 1.

3. a mixing section that mixes the working medium inside the compressor and the working medium injected from the intermediate pressure receiver, The working medium discharged from the mixing section is sucked into a compression section of the compressor. The refrigeration cycle device according to claim 2.

4. The working fluid is a mixture of a plurality of working fluids, and includes at least a working fluid having a boiling point higher than that of the ethylene-based fluoroolefin. The refrigeration cycle device according to any one of claims 1 to 3.

5. An oil separator is provided between the compressor and the outdoor heat exchanger, The oil separated by the oil separator is returned to the compressor. The refrigeration cycle device according to claim 4.

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