Compressor and refrigeration cycle system

Abstract

To effectively suppress or mitigate propagation of a disproportionation reaction of hydrofluoroolefin without being significantly affected by the configuration of a compressor.SOLUTION: In the present invention, a motor unit of a compressor is provided with a plurality of passages whereby a upper space and a lower space inside a sealed container are in communication. A total cross-sectional area of all passages (rotor passages) provided in a rotor of the motor unit is defined as A, a total cross-sectional area of all passages (non-rotor passages) provided outside the rotor is defined as B, a total heat transfer area of all the rotor passages is defined as C, a total heat transfer area of all the non-rotor passages is defined as D, and a cross-sectional area of the sealed container based on an inner diameter thereof is defined as S. In the compressor, A≥B, C≥D, a ratio C / S is 1.0 or more (C / S≥1.0), or a ratio (A+B) / S is 0.05 or more ((A+B) / S≥0.05).SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a compressor that uses a working fluid for a refrigeration cycle containing at least a hydrofluoroolefin as a refrigerant component and that can effectively suppress or mitigate the disproportionation reaction of hydrofluoroolefin, and a refrigeration cycle system using the same. [Background technology]

[0002] As a working medium (refrigerant or heat transfer medium) for the refrigeration cycle, the use of hydrofluoroolefins (HFOs) with a smaller global warming potential (GWP) has been proposed in recent years. A representative hydrofluoroolefin is 1,1,2-trifluoroethylene (HFO1123). 1,1,2-trifluoroethylene is less stable than conventional HFCs and is less likely to remain in the atmosphere, and therefore has a smaller ODP and GWP.

[0003] It is known that such hydrofluoroolefins are prone to undergo a self-decomposition reaction called a disproportionation reaction and a polymerization reaction following this self-decomposition reaction (hereinafter referred to as a disproportionation reaction) due to their low stability. It is also known that the disproportionation reaction is prone to occur due to heat generated during use of the working fluid for the refrigeration cycle, and since the occurrence of the disproportionation reaction is accompanied by a large heat release, the disproportionation reaction may occur in a chain reaction and propagate within the compressor.

[0004] Therefore, for example, Patent Document 1 proposes a configuration in which a metal heat absorbing part is provided inside the compressor in order to suppress the propagation of the disproportionation reaction.

[0005] Specific examples of heat absorbing parts include metal members arranged around the moving parts of the compressor (e.g., the motor or crankshaft), metal members arranged around the inside of the terminal pin (inner pin), and metal members constituting the compressor itself (e.g., the casing). In the compressor described in Patent Document 1, even if a disproportionation reaction occurs in the hydrofluoroolefin contained in the refrigerant, these heat absorbing parts absorb the heat generated by the disproportionation reaction. This prevents the refrigerant from excessively increasing in temperature, thereby preventing the disproportionation reaction from spreading. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2022-027634 A Summary of the Invention [Problem to be solved by the invention]

[0007] However, in the compressor described in Patent Document 1, the installation of the heat absorption part is limited to a configuration in which a heat absorption part is additionally provided to the compressor, which may result in an insufficient heat capacity of the heat absorption part, making it impossible to effectively absorb the heat of the disproportionation reaction generated in the hydrofluoroolefin, and thus making it impossible to effectively suppress the propagation of the disproportionation reaction.

[0008] The present invention has been made to solve these problems, and an object of the present invention is to effectively suppress or mitigate the propagation of the disproportionation reaction of hydrofluoroolefins without being significantly affected by the configuration of the compressor. [Means for solving the problem]

[0009] In order to solve the above-mentioned problems, the compressor according to the present disclosure is a compressor that uses a working medium for a refrigeration cycle containing at least a hydrofluoroolefin as a refrigerant component, and includes an electric motor unit having a rotor and a stator, a compression mechanism unit driven by the electric motor unit, and a sealed container that houses the electric motor unit and the compression mechanism unit therein, wherein spaces are provided above and below the electric motor unit within the sealed container, and the electric motor unit is provided with a plurality of passages that communicate the upper space with the lower space, and wherein when the total cross-sectional area of ​​all the passages provided in the rotor is A and the total cross-sectional area of ​​all the passages provided other than the rotor is B, A≧B.

[0010] Furthermore, in order to solve the above-mentioned problems, the compressor according to the present disclosure is a compressor that uses a working fluid for a refrigeration cycle containing at least a hydrofluoroolefin as a refrigerant component, and includes an electric motor unit having a rotor and a stator, a compression mechanism unit driven by the electric motor unit, and an airtight container that houses the electric motor unit and the compression mechanism unit therein, wherein spaces are provided above and below the electric motor unit within the airtight container, and the electric motor unit is provided with a plurality of passages that communicate with the upper space and the lower space, and wherein the heat transfer area of ​​the passages is the product of the equivalent diameter d of the passages, the passage length L, and pi (π×d×L), where C is the total heat transfer area of ​​all the passages provided in the rotor, and D is the total heat transfer area of ​​all the passages provided other than the rotor, such that C≧D.

[0011] Furthermore, in order to solve the above-mentioned problems, the compressor according to the present disclosure is a compressor that uses a working fluid for a refrigeration cycle containing at least a hydrofluoroolefin as a refrigerant component, and includes an electric motor unit having a rotor and a stator, a compression mechanism unit driven by the electric motor unit, and a sealed container that houses the electric motor unit and the compression mechanism unit therein, wherein spaces are provided above and below the electric motor unit within the sealed container, and the electric motor unit is provided with a plurality of passages that communicate the upper space with the lower space, and wherein a heat transfer area of ​​the passages is defined as the product of an equivalent diameter d of the passages, a passage length L and pi (π×d×L), a total heat transfer area of ​​all the passages provided in the rotor is defined as C, and a cross-sectional area of ​​the sealed container based on an inner diameter of the sealed container is defined as S, where C / S is a ratio of the total heat transfer area C to the cross-sectional area S of 1.0 or more (C / S≧1.0).

[0012] Furthermore, in order to solve the above-mentioned problems, the compressor according to the present disclosure is a compressor that uses a working fluid for a refrigeration cycle containing at least a hydrofluoroolefin as a refrigerant component, and includes an electric motor unit having a rotor and a stator, a compression mechanism unit driven by the electric motor unit, and a sealed container that houses the electric motor unit and the compression mechanism unit therein, wherein spaces are provided above and below the electric motor unit within the sealed container, and the electric motor unit is provided with a plurality of passages that communicate the upper space with the lower space, and among the passages, a total cross-sectional area of ​​all the passages provided in the rotor is A, a total cross-sectional area of ​​all the passages provided other than the rotor is B, and further, a cross-sectional area of ​​the sealed container based on an inner diameter of the sealed container is S, whereby a ratio (A+B) / S of the total cross-sectional area (A+B) of all the passages to the cross-sectional area S of the sealed container is 0.05 or more ((A+B) / S≧0.05).

[0013] According to any of the above configurations, the cross-sectional area or heat transfer area of ​​the rotor passage provided in the rotor among the multiple passages provided in the electric motor section is made relatively large, or a lower limit of the total cross-sectional area or total heat transfer area of ​​the multiple passages is specified based on the cross-sectional area of ​​the sealed container. This makes it possible to predominate the rotor passage that is relatively difficult to propagate the disproportionation reaction among all the passages provided in the electric motor section, and as a result, it is possible to effectively suppress the disproportionation reaction occurring in the space above or below the electric motor section from propagating to the space on the opposite side.

[0014] Furthermore, by suppressing the propagation of the disproportionation reaction, the cooling effect of the motor section, which is the main function of the multiple passages, can calm down and ultimately eliminate the disproportionation reaction itself. As a result, the possibility of a large-scale disproportionation reaction occurring throughout the entire inside of the compressor can be effectively suppressed or avoided, and the reliability of the compressor can be further improved, as well as the reliability of the refrigeration cycle system including this compressor.

[0015] The present disclosure also includes a refrigeration cycle system that uses a working fluid for a refrigeration cycle that contains at least a hydrofluoroolefin as a refrigerant component and is equipped with a compressor having any of the above configurations. Effect of the Invention

[0016] With the above-described configuration, the present invention has the effect of effectively suppressing or mitigating the propagation of the disproportionation reaction of hydrofluoroolefins without being significantly affected by the configuration of the compressor. [Brief description of the drawings]

[0017] [Figure 1] 1 is a schematic vertical cross-sectional view illustrating an example of a compressor according to an embodiment of the present disclosure. [Diagram 2] 2 is a schematic cross-sectional view showing an example of a passage of a motor section in the compressor shown in FIG. 1. [Diagram 3]2A and 2B are schematic block diagrams showing an example of a refrigeration cycle system including the compressor shown in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] [Knowledge that formed the basis of this disclosure] The compressor described in Patent Document 1 is based on the premise that the internal volume of the compressor, i.e., the volume of the sealed container (compressor shell), does not change substantially. Therefore, there are cases where the volume for installing the heat absorption part in the sealed container cannot be sufficiently secured. In such cases, the heat absorption part cannot retain a sufficient heat capacity to absorb the heat of the disproportionation reaction, and as a result, there is a possibility that the propagation of the disproportionation reaction cannot be effectively suppressed.

[0019] Therefore, in order to secure the volume for installing the heat absorbing part, it becomes necessary to increase the internal volume of the sealed container. In this case, it is not enough to simply increase the internal volume, but it is also necessary to review the pressure resistance design of the sealed container. Furthermore, increasing the internal volume of the sealed container means that the compressor itself becomes excessively large, which promotes the chain reaction of disproportionation reactions.

[0020] As described above, the heat absorbing parts of the compressor described in Patent Document 1 include metal members arranged around the moving parts of the compressor, metal members arranged around the inside of the terminal pin, and metal members constituting the compressor itself. In other words, these heat absorbing parts are members installed in areas where high temperature and pressure are expected (moving parts of the compressor), members installed in areas that may trigger a disproportionation reaction (inside the terminal pin), or existing members that the compressor is equipped with.

[0021] In other words, these endothermic parts are not installed with consideration given to how the disproportionation reaction of hydrofluoroolefins generated in the compressor propagates in the compressor. Therefore, the heat generated when the disproportionation reaction occurs inside the compressor does not necessarily propagate selectively around the endothermic parts. As a result, there is a possibility that these endothermic parts cannot absorb the heat of the disproportionation reaction well.

[0022] Therefore, as a result of intensive research, the inventors have independently discovered that the inside of the compressor can be divided into an upper space and a lower space when viewed from the electric motor section, that the disproportionation reaction of hydrofluoroolefin occurs in either the upper space or the lower space and then propagates to the other space via a plurality of passages provided in the electric motor section that communicate these spaces, and that, of the passages provided in the electric motor section, the passages provided in the rotor are less likely to promote the disproportionation reaction than passages provided outside the rotor, and have thus completed the present invention.

[0023] That is, the compressor according to the present disclosure is a compressor that uses a working medium for a refrigeration cycle containing at least a hydrofluoroolefin as a refrigerant component, and is equipped with an electric motor unit having a rotor and a stator, a compression mechanism unit driven by the electric motor unit, and a sealed container that houses the electric motor unit and the compression mechanism unit, wherein spaces are provided above and below the electric motor unit within the sealed container, and the electric motor unit is provided with a plurality of passages that communicate the upper space with the lower space, and wherein, when the total cross-sectional area of ​​all the passages provided in the rotor is A and the total cross-sectional area of ​​all the passages provided other than the rotor is B, then A≧B.

[0024] Alternatively, the compressor according to the present disclosure may be a compressor that uses a working fluid for a refrigeration cycle containing at least a hydrofluoroolefin as a refrigerant component, and includes an electric motor unit having a rotor and a stator, a compression mechanism unit driven by the electric motor unit, and an airtight container that houses the electric motor unit and the compression mechanism unit, wherein spaces are provided above and below the electric motor unit within the airtight container, and the electric motor unit is provided with a plurality of passages that communicate the upper space with the lower space, and wherein the heat transfer area of ​​the passages is the product of the equivalent diameter d of the passages, the passage length L, and pi (π×d×L), where C is the total heat transfer area of ​​all the passages provided in the rotor and D is the total heat transfer area of ​​all the passages provided other than the rotor, such that C≧D.

[0025] Alternatively, the compressor according to the present disclosure may be a compressor that uses a working fluid for a refrigeration cycle containing at least a hydrofluoroolefin as a refrigerant component, and includes an electric motor unit having a rotor and a stator, a compression mechanism unit driven by the electric motor unit, and a sealed container that houses the electric motor unit and the compression mechanism unit, wherein spaces are provided above and below the electric motor unit within the sealed container, and the electric motor unit is provided with a plurality of passages that communicate the upper space with the lower space, and wherein a heat transfer area of ​​the passage is defined as the product of an equivalent diameter d of the passage, a passage length L and pi (π×d×L), a total heat transfer area of ​​all the passages provided in the rotor is defined as C, and a cross-sectional area of ​​the sealed container based on an inner diameter of the sealed container is defined as S, and the ratio C / S of the total heat transfer area C to the cross-sectional area S is 1.0 or more (C / S≧1.0).

[0026] Alternatively, the compressor according to the present disclosure may be a compressor that uses a working fluid for a refrigeration cycle containing at least a hydrofluoroolefin as a refrigerant component, and includes an electric motor unit having a rotor and a stator, a compression mechanism unit driven by the electric motor unit, and a sealed container that houses the electric motor unit and the compression mechanism unit, wherein spaces are provided above and below the electric motor unit within the sealed container, and the electric motor unit is provided with a plurality of passages that communicate the upper space with the lower space, and among the passages, a total cross-sectional area of ​​all the passages provided in the rotor is A, a total cross-sectional area of ​​all the passages provided other than the rotor is B, and further, a cross-sectional area of ​​the sealed container based on an inner diameter of the sealed container is S, whereby a ratio (A+B) / S of the total cross-sectional area (A+B) of all the passages to the cross-sectional area S of the sealed container is 0.05 or more ((A+B) / S≧0.05).

[0027] According to any of the above configurations, the cross-sectional area or heat transfer area of ​​the rotor passage provided in the rotor among the multiple passages provided in the electric motor section is relatively large, or the lower limit of the total cross-sectional area or total heat transfer area of ​​the multiple passages is specified based on the cross-sectional area of ​​the sealed container. This makes it possible to make the cooling effect of the rotor passage dominant among all the passages provided in the electric motor section, and as a result, it is possible to effectively suppress the disproportionation reaction occurring in the space above or below the electric motor section from propagating to the space on the opposite side.

[0028] Furthermore, by suppressing the propagation of the disproportionation reaction, the cooling effect of the motor section, which is the main function of the multiple passages, can calm down and ultimately eliminate the disproportionation reaction itself. As a result, the possibility of a large-scale disproportionation reaction occurring throughout the entire inside of the compressor can be effectively suppressed or avoided, and the reliability of the compressor can be further improved, as well as the reliability of the refrigeration cycle system including this compressor.

[0029] In the compressor having the above configuration, the passage provided other than the rotor may be at least one of an air gap passage formed between the rotor and the stator, and a stator passage provided between the stator and the sealed container.

[0030] In the compressor having the above configuration, the hydrofluoroolefin may be at least one of 1,1,2-trifluoroethylene (HFO1123) and 1,2-difluoroethylene (HFO1132).

[0031] In the compressor having the above configuration, the working fluid for the refrigeration cycle may further contain difluoromethane as a refrigerant component and may contain at least one of saturated hydrocarbons, haloalkanes, and fluoroalkanes having 1 to 3 carbon atoms and a boiling point of 0°C or lower (excluding difluoromethane) as a disproportionation inhibitor.

[0032] The present disclosure further includes a refrigeration cycle system that uses a working fluid for a refrigeration cycle that contains at least a hydrofluoroolefin as a refrigerant component and is equipped with a compressor having any of the above configurations.

[0033] Hereinafter, a representative embodiment of the present invention will be described with reference to the drawings. In the following, the same or corresponding components are denoted by the same reference numerals throughout the drawings, and duplicated descriptions thereof will be omitted.

[0034] [Refrigerant components] In the compressor according to the present disclosure, a working fluid for a refrigeration cycle is used that contains, as a refrigerant component, at least a hydrofluoroolefin (HFO) in which a disproportionation reaction occurs.

[0035] Specific examples of hydrofluoroolefins include, but are not limited to, those having a carbon number of 2, such as 1,1,2-trifluoroethylene (CF2=CHF, HFO1123), trans-1,2-difluoroethylene (CHF=CHF(E), HFO1132(E)), and cis-1,2-difluoroethylene (CHF=CHF(Z), HFO1132(Z)). Only one of these hydrofluoroolefins may be used as a refrigerant component, or two or more of them may be used in combination as a refrigerant component.

[0036] These hydrofluoroolefins have a skeleton ethylene structure, i.e., a double bond between carbon atoms, and have a chemical structure in which at least one of the two hydrogen atoms bonded to one carbon atom is replaced by a fluorine atom, or at least one of the two hydrogen atoms bonded to both carbon atoms is replaced by a fluorine atom. Note that in the hydrofluoroolefins, some of the hydrogen atoms may be replaced by other atoms or other substituents.

[0037] For example, 1,1,2-trifluoroethylene has a structure in which both of the two hydrogen atoms bonded to one carbon atom of the ethylene structure (the carbon atom at position 1) are replaced by fluorine atoms, and one of the two hydrogen atoms bonded to the other carbon atom (the carbon atom at position 2) is replaced by a fluorine atom.

[0038] Alternatively, trans-1,2-difluoroethylene has a structure in which one of the two hydrogen atoms bonded to the carbon atom at position 1 of the ethylene structure is substituted with a fluorine atom, and of the two hydrogen atoms bonded to the carbon atom at position 2, only the hydrogen atom facing the carbon atom at position 1 across the double bond, not the hydrogen atom adjacent to the carbon atom at position 2, is substituted with a fluorine atom.

[0039] As described above, such hydrofluoroolefins contain an ethylene skeleton, i.e., a carbon-carbon double bond, and this double bond is easily decomposed. That is, ozone in the atmosphere generates hydroxyl radicals (OH radicals) through photochemical reactions, and these hydroxyl radicals can cause addition reactions with double bonds, making the hydrofluoroolefins easily decomposed. Therefore, hydrofluoroolefins have little impact on ozone layer destruction and global warming.

[0040] The working fluid for a refrigeration cycle used in the present disclosure may contain difluoromethane (HFC32, R32, chemical formula: CH2F2) as a refrigerant component in addition to the hydrofluoroolefin. In this case, if the hydrofluoroolefin is considered to be the "main component (principal refrigerant component)" of the refrigerant components in the working fluid for a refrigeration cycle used in the present disclosure, the difluoromethane is considered to be the "secondary component (secondary refrigerant component)" of the refrigerant components in the working fluid for a refrigeration cycle used in the present disclosure.

[0041] As mentioned above, difluoromethane has an ozone depletion potential (ODP) of 0 and has good refrigerant performance compared to the HCFCs (hydrochlorofluorocarbons) that have been used up until now.

[0042] In addition, the working fluid for the refrigeration cycle used in the present disclosure may contain "other refrigerant components" in addition to the hydrofluoroolefin as the main refrigerant component and difluoromethane as the secondary refrigerant component. Representative examples of the other refrigerant components include hydrofluorocarbons (HFCs) such as difluoroethane, trifluoroethane, tetrafluoroethane, pentafluoroethane, pentafluoropropane, hexafluoropropane, heptafluoropropane, pentafluorobutane, and heptafluorocyclopentane; hydrofluoroolefins (HFOs) having 3 or more carbon atoms such as monofluoropropene, trifluoropropene, tetrafluoropropene, pentafluoropropene, and hexafluorobutene, but are not particularly limited thereto.

[0043] These other refrigerant components are known to have little impact on ozone depletion and global warming, and therefore can be used together with hydrofluoroolefins, or hydrofluoroolefins and difluoromethane, as refrigerant components. The above-mentioned other refrigerant components may be used alone or in appropriate combination of two or more.

[0044] The content of hydrofluoroolefin in the working fluid for a refrigeration cycle is not particularly limited, but when the total amount of the refrigerant components and the disproportionation inhibitor described below among the components constituting the working fluid for a refrigeration cycle (for convenience of explanation, referred to as the "total amount of refrigerant-related components") is taken as 100% by mass, the content of hydrofluoroolefin may be 40% by mass or more, and although the lower limit of the content of hydrofluoroolefin may be 40% by mass as described above, it is preferably 45% by mass or more, more preferably 50% by mass or more, and even more preferably 70% by mass or more.

[0045] If the content of the hydrofluoroolefin is less than 40% by mass of the total amount of the refrigerant-related components, the content of the hydrofluoroolefin in the working fluid for the refrigeration cycle will be too low, resulting in the content of other refrigerant components being too high, and therefore the advantage of using the hydrofluoroolefin with a small GWP in the working fluid for the refrigeration cycle will not be fully obtained.

[0046] The upper limit of the hydrofluoroolefin content is not particularly limited, but may be 98.8 mass% or less of the total amount of refrigerant-related components. As described later, in the present disclosure, the working fluid for a refrigeration cycle may contain a disproportionation inhibitor that is gaseous or liquid at normal temperature and pressure. A preferred lower limit of the content of this disproportionation inhibitor is 1.2 mass%. Therefore, if only hydrofluoroolefin is used as the refrigerant component and no other refrigerant components are used (100 mass% of hydrofluoroolefin is used as the refrigerant component), the upper limit of the hydrofluoroolefin content in the total amount of refrigerant-related components is necessarily 98.8 mass%.

[0047] When the refrigerant component contains other refrigerant components than hydrofluoroolefin, the content of the other refrigerant components is not particularly limited. For example, as mentioned above, a preferred example of the other refrigerant components is difluoromethane, but since the preferred upper limit of the content of hydrofluoroolefin, which is an essential refrigerant component, is 40% by mass of the total amount of the refrigerant-related components, the content of difluoromethane may be less than 60% by mass of the total amount of the refrigerant-related components. In addition, when the refrigerant component contains other refrigerant components, a particularly preferred example of the content of hydrofluoroolefin can be in the range of 70% by mass to 80% by mass, but is not limited thereto.

[0048] [Other ingredients that can be used in combination] The working fluid for the refrigeration cycle used in the present disclosure is used in a refrigeration cycle system, and therefore can be used in combination with a lubricating oil (refrigerating machine oil) that lubricates a hermetic compressor equipped in the refrigeration cycle system. As described above, the working fluid for the refrigeration cycle used in the present disclosure may be at least composed of a refrigerant component that is substantially a "main component" of hydrofluoroolefin. Furthermore, when the working fluid for the refrigeration cycle is used in combination with a lubricating oil, the working fluid-containing composition can be considered to be composed of the refrigerant component, the lubricating oil component, and other components.

[0049] The lubricating oil component contained in the working fluid-containing composition (used together with the working fluid for the refrigeration cycle) can be suitably selected from various lubricating oils known in the refrigeration cycle system. Specific examples of the lubricating oil include, but are not limited to, ester-based lubricating oils, ether-based lubricating oils, glycol-based lubricating oils, alkylbenzene-based lubricating oils, fluorine-based lubricating oils, mineral oils, and hydrocarbon-based synthetic oils. Only one type of these lubricating oils may be used, or two or more types may be used in appropriate combination.

[0050] In addition, various known additives may be added to the working medium-containing composition. Specific additives include, but are not limited to, antioxidants, moisture scavengers, metal deactivators, antiwear agents, and antifoamers. Antioxidants are used to improve the thermal stability, oxidation resistance, chemical stability, and the like of refrigerant components or lubricating oils. Moisture scavengers are used to remove moisture when moisture infiltrates into a refrigeration cycle system, and are particularly used to suppress changes in the properties of lubricating oils. Metal deactivators are used to suppress or prevent chemical reactions caused by the catalytic action of metal components. Antiwear agents are used to reduce wear in sliding parts in compressors, particularly wear during high-pressure operation. Antifoamers are used to suppress the generation of bubbles in lubricating oils.

[0051] The specific types of these additives are not particularly limited, and known compounds can be suitably used depending on various conditions. In addition, as these additives, only one type of compound may be used, or two or more types of compounds may be appropriately combined. Furthermore, the amount of these additives added is not particularly limited, and they can be added within a known range as long as it does not impair the properties of the working fluid for the refrigeration cycle used in the present disclosure or the working fluid-containing composition containing the same.

[0052] Here, as described above, the working fluid for a refrigeration cycle used in the present disclosure may have a disproportionation inhibitor that is gaseous or liquid at normal temperature and normal pressure added to it in advance. Specifically, for example, the disproportionation inhibitor may be at least one of saturated hydrocarbons having 2 to 5 carbon atoms, haloalkanes having 1 or 2 carbon atoms except for those in which all halogen atoms are fluorine, and fluoroalkanes having 1 to 3 carbon atoms (excluding difluoromethane) having a boiling point of 0° C. or less. Only one of these disproportionation inhibitors may be used, or two or more of them may be used in appropriate combination.

[0053] Specific examples of disproportionation inhibitors include, but are not limited to, saturated hydrocarbons such as ethane, n-propane, cyclopropane, n-butane, cyclobutane, isobutane (2-methylpropane), methylcyclopropane, n-pentane, isopentane (2-methylbutane), neopentane (2,2-dimethylpropane), methylcyclobutane, etc. Among these, n-propane is particularly preferred.

[0054] Examples of haloalkanes having one carbon atom, that is, halomethanes, include, but are not limited to, (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 (CHFI2), difluorodiiodomethane (CF2I2), dibromodifluoromethane (CBr2F2), trifluoroiodomethane (CF3I), difluoroiodomethane (CHF2I), and the like. Among these, dibromomethane (CH2Br2), bromomethane (CH3Br), dibromodichloromethane (CBr2Cl2), trifluoroiodomethane (CF3I) and the like are preferred, with trifluoroiodomethane (CF3I) being more preferred.

[0055] Examples of haloalkanes having 2 carbon atoms, i.e., haloethanes, include 1,1,1-trifluoro-2-iodoethane (CF3CH2I), monoiodoethane (CH3CH2I), monobromoethane (CH3CH2Br), 1,1,1-triiodoethane (CH3CI3), etc. Among these, 1,1,1-trifluoro-2-iodoethane (CF3CH2I) is particularly preferably used in consideration of availability, ODP value, handling, etc.

[0056] Examples of fluoroalkanes having 1 to 3 carbon atoms include fluoromethane (boiling point -78.2°C), difluoromethane (boiling point -51.6°C), trifluoromethane (boiling point -84.4°C), and tetrafluoromethane (boiling point -127.8°C); fluoroethane (boiling point -37.1°C), 1,1-difluoroethane (boiling point -24.7°C), 1,1,1-trifluoroethane (boiling point -47.2°C), 1,1,1,2-tetrafluoroethane (boiling point -26.3°C), 1, Examples of the fluoroethanes include 1,1,2,2-pentafluoroethane (boiling point: -48.5°C); and fluoropropanes such as 1-fluoropropane (boiling point: -2.5°C), 2-fluoropropane (boiling point: -10.0°C), 2,2-difluoropropane (boiling point: -1.0°C), 1,1,1-trifluoropropane (boiling point: -12.0°C), 1,1,2,2-tetrafluoropropane (boiling point: -0.8°C), and 1,1,1,3,3,3-hexafluoropropane (boiling point: -1.4°C).

[0057] The amount of disproportionation inhibitor to be added is not particularly limited, but when the total amount of refrigerant-related components (total amount of refrigerant components and disproportionation inhibitor) is taken as 100 mass%, the upper limit of the amount (content) of the disproportionation inhibitor to be added may be 10 mass% or less of the total amount of refrigerant-related components, preferably 5 mass% or less, and more preferably 3 mass% or less. This is because if the content of the disproportionation inhibitor exceeds 10 mass% of the total amount of refrigerant-related components, the content of the disproportionation inhibitor becomes too high when viewed as a working fluid for a refrigeration cycle, and there is a possibility that the working fluid will not be able to exhibit good physical properties as a "refrigerant". Of course, depending on the composition of the working fluid for a refrigeration cycle, 10 mass% or more of the total amount of refrigerant-related components may be added.

[0058] As the disproportionation inhibitor, as described above, two or more of saturated hydrocarbons, haloalkanes, and fluoroalkanes can be used in combination. At this time, the mixing ratio of saturated hydrocarbons, haloalkanes, and fluoroalkanes is not particularly limited. As described above, the preferred content of the total amount of disproportionation inhibitors can be 10 mass% or less, so it is sufficient that two or more of saturated hydrocarbons, haloalkanes, and fluoroalkanes are used in combination in an appropriate mixing ratio within this range.

[0059] In the present disclosure, a plurality of types of compounds may be used in combination as each of saturated hydrocarbons, haloalkanes, and fluoroalkanes. Therefore, the combination of two or more types of saturated hydrocarbons, haloalkanes, and fluoroalkanes means that two or more types of compounds may be used in combination among one or more types of compounds classified as saturated hydrocarbons, one or more types of compounds classified as haloalkanes, and one or more types of compounds classified as fluoroalkanes.

[0060] Here, the saturated hydrocarbon, haloalkane, and fluoroalkane can suppress or slow down the progress of the disproportionation reaction even when added in an amount of 10% by mass or less. Furthermore, as disclosed herein, when two or more of the saturated hydrocarbon, haloalkane, and fluoroalkane are used in combination, it is possible to suppress or slow down the progress of the disproportionation reaction with even smaller amounts than when each is added alone. More specifically, the upper limit of the amount of disproportionation inhibitor added in the total amount (total amount of two or more of the saturated hydrocarbon, haloalkane, and fluoroalkane) may be 10% by mass or less, and may be 5% by mass or less, but when the saturated hydrocarbon and the haloalkane are combined, a more preferable upper limit is 3% by mass or less.

[0061] At this time, the mixing ratio of two or more of the saturated hydrocarbon, haloalkane, and fluoroalkane is not particularly limited. For example, in the case of using a combination of a saturated hydrocarbon and a haloalkane, when the amount added is 3 mass% or less, a representative example of the mixing ratio of the saturated hydrocarbon and the haloalkane can be in the range of 1:0.5 to 1:2 by mass. Here, there are three combinations of saturated hydrocarbons and haloalkanes, and the representative mixing ratios for each combination are as follows: [1] A combination of three types of saturated hydrocarbons, haloethane, and halomethane can be in the range of 1:0.25:0.25 to 1:1:1 by mass; [2] A combination of two types of saturated hydrocarbons and haloethane can be in the range of 1:0.25 to 1:1; and [3] A combination of two types of saturated hydrocarbons and halomethane can be in the range of 1:0.25 to 1:1.

[0062] The lower limit of the amount of two or more of saturated hydrocarbons, haloalkanes, and fluoroalkanes is not particularly limited, but a representative lower limit is 1.2 mass% or more of the total amount of refrigerant-related components. Even if the total amount of two or more of saturated hydrocarbons, haloalkanes, and fluoroalkanes is less than 1.2 mass%, it is possible to obtain the effect of suppressing disproportionation reactions, but if it is 1.2 mass% or more, the effect of suppressing disproportionation reactions can be more suitably realized. Therefore, in the present disclosure, a more preferable range of the content of two or more of saturated hydrocarbons, haloalkanes, and fluoroalkanes is 1.2 mass% or more and 3 mass% or less of the total amount of refrigerant-related components.

[0063] [Compressor configuration example] Next, a representative example of the compressor according to the present disclosure will be described. The compressor according to the present disclosure is not particularly limited in its specific configuration as long as it uses the above-mentioned working fluid for a refrigeration cycle, that is, a working fluid for a refrigeration cycle containing a hydrofluoroolefin in which a disproportionation reaction occurs as a refrigerant component, but a representative example is a rotary compressor 30 shown in FIG. 1. This rotary compressor 30 is a representative example of a compressor used in a home air conditioner described later. This air conditioner is an example of a refrigeration cycle system (or refrigeration cycle device) according to the present disclosure.

[0064] The compressor 30 includes an electric motor section 41 and a compression mechanism section 42 housed in a sealed container 31 (or a compressor shell). The sealed container 31 is a vertically long cylinder, and in the configuration shown in Fig. 1, for example, is made up of an upper shell 32, a body shell 33, and a lower shell 34. The upper shell 32 forms the upper part of the sealed container 31, the lower shell 34 forms the lower part of the sealed container 31, and the body shell 33 forms the majority of the sealed container 31 (the main body of the sealed container 31). The upper shell 32 and the lower shell 34 are fitted into the body shell 33. In addition, a discharge pipe 35 is provided in the upper shell 32, and a suction pipe 36 is formed on the lower side of the body shell 33.

[0065] The electric motor unit 41 is a motor including a rotor 43 and a stator 44, and the rotor 43 is provided with a shaft 45. The shaft 45 is rotatably connected to a piston 46 included in the compression mechanism unit 42, and the piston 46 rotates within a cylinder 47 included in the compression mechanism unit 42. Therefore, the compression mechanism unit 42 is driven by the electric motor unit 41.

[0066] 1, the electric motor unit 41 is located at the upper side within the sealed container 31, and the compression mechanism unit 42 is located below the electric motor unit 41. Therefore, the electric motor unit 41 is located at the upper part of the internal space of the sealed container 31, and the compression mechanism unit 42 is located at the lower part of the internal space. Lubricating oil 48 is also sealed within the sealed container 31. In the example shown in FIG. 1, the lubricating oil 48 is stored below the compression mechanism unit 42 within the sealed container 31 (at the bottom of the sealed container 31).

[0067] The cylinder 47 of the electric motor unit 41 and the compression mechanism unit 42 has an outer diameter almost the same as the inner diameter of the cylindrical sealed container 31, and the shaft 45 rotates due to the rotation of the electric motor unit 41, and this rotational driving force is transmitted to the piston 46 of the compression mechanism unit 42. The piston 46 rotates within the cylinder 47 due to the rotational driving force of the electric motor unit 41. A low-pressure gas refrigerant is introduced into the cylinder 47 from the suction pipe 36, compressed by the rotation of the cylinder 47, and discharged as a high-pressure refrigerant gas into the inside of the sealed container 31 (below the electric motor unit 41), after which it flows to the upper part of the electric motor unit 41 through a passage provided in the electric motor unit 41, and is discharged from the discharge pipe 35 at the upper end of the sealed container 31 to the outside of the compressor 30.

[0068] Here, in the sealed container 31 of the compressor 30, spaces 31a, 31b are provided above and below the electric motor unit 41. In the example shown in Fig. 1, in the sealed container 31, the internal space extending from the top of the electric motor unit 41 to the upper shell 32 is the upper space 31a, and the internal space between the bottom of the electric motor unit 41 and the top of the compression mechanism unit 42 is the lower space 31b. In the compressor 30 according to the present disclosure, as shown in Fig. 2 in addition to Fig. 1, a plurality of passages 43a, 44a, 44b that communicate between the upper space 31a and the lower space 31b are provided in the electric motor unit 41.

[0069] These multiple passages 43a, 44a, 44b can be divided into a passage 43a provided in the rotor 43 of the electric motor section 41, and passages 44a, 44b provided outside the rotor 43. For ease of explanation, the former is referred to as the rotor passage 43a, and the latter are referred to as the extra-rotor passages 44a, 44b.

[0070] 1 is a schematic longitudinal section of the compressor 30, while FIG. 2 is a schematic transverse section of the compressor 30, which corresponds to a transverse section of the portion of the motor unit 41 where the rotor 43 and the stator 44 are located. In this disclosure, a section along the vertical direction of the compressor 30 is defined as a longitudinal section, and a section along a direction perpendicular to the vertical direction is defined as a transverse section. The "cross-sectional area of ​​the passage" or the "cross-sectional area of ​​the sealed container (compressor 30)" described later means the area of ​​the transverse section. In addition, in FIG. 2, the rotor 43 and the stator 44 are diagrammatically hatched to clearly show the passages 43a, 44a, and 44b, but of course the rotor 43 and the stator 44 do not have the simple structure as shown in FIG. 2.

[0071] As shown by dotted lines in Fig. 1, the rotor passages 43a are provided so as to penetrate the rotor 43 along the axial direction of the rotor 43. In the example shown in Fig. 2, the rotor passages 43a are provided at six equally spaced locations between the outer peripheral surface and the inner peripheral surface of the rotor 43 so as to have the same radius as seen from the rotation axis, and have an elliptical cross section. However, the specific configuration of the rotor passages 43a is not limited thereto. As long as the rotor passages 43a do not impede the proper rotation performance of the rotor 43, they may be formed inside the rotor 43 so as to communicate the upper space 31a and the lower space 31b, and the number of the rotor passages is also not particularly limited.

[0072] Of the rotor outer passages 44a and 44b, the stator passage 44a is formed between the sealed container 31 (body shell 33 in FIG. 2) and the stator 44 so as to be recessed toward the inside of the stator 44 (toward the shaft 45). In FIG. 1, the stator passage 44a is illustrated by a dotted line, similar to the rotor passage 43a. In the example shown in FIG. 2, the stator passages 44a are provided at ten locations at equal intervals on the outer surface of the stator 44, and have a semicircular cross section. However, the specific configuration of the stator passage 44a is not limited thereto. As long as the function of the stator 44 is not hindered, the stator passages 44a may be formed on the outer surface of the stator 44 so as to communicate the upper space 31a and the lower space 31b, and the number of the stator passages is not particularly limited.

[0073] Of the rotor outer passages 44a and 44b, the air gap passage 44b utilizes an air gap, which is a gap generated between the rotor 43 and the stator 44, as the rotor outer passage. In general, an air gap, which is a cylindrical space, is formed between the rotor 43 and the stator 44. Therefore, in the present disclosure, the air gap passage 44b can utilize the air gap that is usually provided in the electric motor section 41 as it is.

[0074] Here, the air gap is set as narrow as possible within a range where the rotor 43 and the stator 44 do not come into mechanical contact with each other. This is because making the air gap narrower (smaller) makes it possible to strengthen the magnetic field and improve the power density of the rotor 43. Conversely, from the viewpoint of using the air gap as a rotor outer passage, the air gap may be widened within a range where the required power density of the rotor 43 can be achieved.

[0075] In this embodiment, the stator passage 44a and the air gap passage 44b are given as examples of the rotor outer passage, but specific configuration examples of the rotor outer passage are not limited to these, and a passage other than the stator passage 44a or the air gap passage 44b may be provided in a portion other than the rotor 43. Also, for example, if the air gap passage 44b alone can satisfactorily communicate the upper space 31a and the lower space 31b, the stator passage 44a does not need to be provided. Alternatively, if the stator passage 44a alone can satisfactorily communicate the upper space 31a and the lower space 31b, the air gap may be made as narrow as possible without functioning satisfactorily as a passage.

[0076] In the compressor 30 according to the present disclosure, in the above-described configuration, in particular, predetermined conditions are set for the cross-sectional area and / or heat transfer area between at least two or more components among the group of components consisting of the rotor passage 43a and the rotor outer passage of the electric motor section 41, and the sealed container 31.

[0077] Specifically, there are the following conditions: [Condition 1] When the total cross-sectional area of ​​the rotor passage 43a is A and the total cross-sectional area of ​​the rotor outer passages is B, A≧B; [Condition 2] When the total heat transfer area of ​​the rotor passage 43a is C and the total heat transfer area of ​​the rotor outer passages is D, C≧D; [Condition 3] When the cross-sectional area of ​​the sealed container 31 based on the inner diameter of the sealed container 31 (container cross-sectional area) is S, the ratio C / S of the total heat transfer area C of the rotor passage 43a to the container cross-sectional area S is 1.0 or more (C / S≧1.0); and [Condition 4] The ratio (A+B) / S of the total cross-sectional area A of all the passages 43a, 44a, 44b (i.e. the sum of the total cross-sectional area A of the rotor passage 43a and the total cross-sectional area B of the rotor outer passages) to the container cross-sectional area S is 0.05 or more ((A+B) / S≧0.05).

[0078] Among the above conditions 1 to 4, the heat transfer areas of the passages 43a, 44a, and 44b under conditions 2 and 3 are calculated as the product (π×d×L) of the equivalent diameter d of each passage, the passage length L, and pi.

[0079] As a result, within the internal space of the sealed container 31, the area above the electric motor unit 41 is the upper space 31a as described above, and the area below the electric motor unit 41 is the lower space 31b, so that, for example, when a disproportionation reaction of hydrofluoroolefin occurs in the upper space 31a, the disproportionation reaction can be effectively prevented from propagating to the other lower space 31b. Even when a disproportionation reaction occurs in the lower space 31b, the disproportionation reaction can be effectively prevented from propagating to the other upper space 31a.

[0080] The electric motor section 41 of the compressor 30 generates heat during operation, which leads to a decrease in performance or the occurrence of abnormalities. For this reason, in general, a passage is provided in the electric motor section 41, and a working medium for a refrigeration cycle is passed through this passage to cool the electric motor section 41. For the purpose of cooling the electric motor section 41, a passage may be provided in the rotor 43 or a passage may be provided in the stator 44.

[0081] 1, the electric motor unit 41 is positioned without any gaps so as to be "filled" in the cross-sectional direction inside the sealed container 31. In such a configuration, the working fluid for the refrigeration cycle discharged from the compression mechanism unit 42 below is a "compressed mixed gas" in which the refrigerant components and the lubricating oil 48 are mixed, that is, the above-mentioned working fluid-containing composition.

[0082] Therefore, a passage is provided in the motor section 41, and the compressed gas mixture is passed through the passage, thereby cooling the motor section 41 and separating the lubricating oil 48 from the compressed gas mixture. As a result, a working medium for the refrigeration cycle substantially composed mainly of a refrigerant component is discharged from the discharge pipe 35 located at the top of the sealed container 31.

[0083] In other words, the passages provided in the electric motor section 41 have a function of cooling the electric motor section 41 with the working medium for a refrigeration cycle or the working medium-containing composition, and a function of separating the lubricating oil 48 from the working medium-containing composition in order to discharge substantially the working medium for a refrigeration cycle (almost only the refrigerant component) from the discharge pipe 35. In order to realize such functions, the positions of the passages in the electric motor section 41 are not particularly limited, and any number of passages may be provided at any position in the electric motor section 41, taking into consideration the various conditions required for the compressor 30.

[0084] Here, the present inventors have intensively studied the propagation of the disproportionation reaction in the compressor 30, and found that the disproportionation reaction of hydrofluoroolefin occurs in either the upper space 31a or the lower space 31b. The disproportionation reaction is induced by discharges at the coil end portion that occur during the use of the working fluid for the refrigeration cycle, but it is very rare for the trigger to occur at exactly the same time above or below the motor portion 41, and the disproportionation reaction occurs either above or below. It was thought that the disproportionation reaction then propagates to the other space through a plurality of passages that communicate these spaces 31a and 31b. In addition, it was thought that, among these plurality of passages, the rotor passage 43a provided in the rotor 43 is less likely to propagate the disproportionation reaction than the outer rotor passage.

[0085] In general, there is a correlation between the high temperature and pressure state inside the compressor 30 (inside the sealed container 31) and the rotation speed of the rotor 43. When the rotor 43 is rotating at high pressure, the inside of the compressor 30 is usually at high temperature and pressure. In a situation where a disproportionation reaction occurs in hydrofluoroolefin, the inside of the compressor 30 is basically in a high temperature and pressure state, and the rotor 43 at this time is in a state of rotating at almost high speed. Conversely, when the rotor 43 is rotating at low speed, the disproportionation reaction hardly occurs. Therefore, it is considered that the inside of the compressor 30 does not reach a high temperature and pressure sufficient to cause the disproportionation reaction during low speed rotation.

[0086] It is considered that the passages 43a, 44a, 44b provided in the electric motor section 41 all have substantially the same function in terms of cooling the electric motor section 41 and separating the lubricating oil 48. However, in terms of propagation of the disproportionation reaction, it is considered that the rotor passage 43a is less likely to propagate the disproportionation reaction than the outer-rotor passages such as the passages 44a and 44b.

[0087] The reason for this is believed to be as follows. The refrigerant compressed by the compression mechanism 42 is discharged into the sealed container 31, where it cools the motor 41 and separates the lubricating oil 48. At this time, the refrigerant near the rotor 43 rotating at high speed is partially guided into the rotor passage 43a and partially guided outward from the sealed container 31 by centrifugal force, so that a refrigerant flow is always formed from near the rotor 43 to the stator 44 of the motor 41. Here, in order for a disproportionation reaction occurring at one point above or below the stator 44 of the motor 41 to propagate into the rotor passage 43a rotating at high speed, it must propagate against the flow direction of the refrigerant flow. Therefore, the rotor passage 43a has a characteristic that it is difficult for the disproportionation reaction to propagate.

[0088] Therefore, for example, as per the above-mentioned condition 1, the passages 43a, 44a, 44b provided in the motor section 41 are divided into passage 43a (rotor passage 43a) provided in the rotor 43 and passages 44a, 44b (extra-rotor passages) provided outside the rotor 43, and the total cross-sectional area A of the rotor passage 43a is set to be larger than the total cross-sectional area B of the extra-rotor passages.

[0089] As a result, the electric motor section 41 can be cooled well, and the lubricating oil 48 can be separated well from the compressed mixed gas (working medium-containing composition) discharged from the compression mechanism section 42. Moreover, even if a disproportionation reaction occurs in the upper space 31a, for example, the total cross-sectional area A of the rotor passage 43a is larger than the total cross-sectional area B of the rotor outer passages, so that the disproportionation reaction is unlikely to propagate to the lower space 31b via the rotor passage 43a, and ultimately, the disproportionation reaction itself can be calmed down and eliminated as the electric motor section 41 is cooled.

[0090] In other words, the disproportionation reaction is confined in the upper space 31a by the rotor 43 having the rotor passage 43a with a larger total cross-sectional area, and disappears before propagating to the opposite lower space 31b. In particular, since the disproportionation reaction occurs at the same time as the rotor 43 rotates at high speed under high temperature and pressure, the propagation can be suppressed more effectively.

[0091] The condition 2 is a condition that the total heat transfer area C of the rotor passage 43a is larger than the total heat transfer area D of the rotor outer passages. Therefore, similar to the condition 1, the electric motor section 41 can be well cooled, the lubricating oil 48 can be well separated from the compressed gas mixture, and the disproportionation reaction occurring in the upper space 31a or the lower space 31b can be calmed and eliminated before it propagates to the opposite side.

[0092] The condition 3 is that the ratio C / S of the total heat transfer area C of the rotor passage 43a to the vessel cross-sectional area S (transverse cross-sectional area of ​​the sealed vessel 31) is 1.0 or more. This condition 3 sets the total heat transfer area C of the rotor passage 43a larger with the vessel cross-sectional area S as the standard.

[0093] That is, in the above-mentioned condition 1 or condition 2, the cross-sectional area or heat transfer area is set for two components, the rotor passage 43a and the rotor outer passage, among the group of components consisting of the rotor passage 43a, the rotor outer passage, and the sealed container 31. On the other hand, in condition 3, the heat transfer area and the cross-sectional area ratio are set for the rotor passage 43a and the sealed container 31.

[0094] Here, in condition 3, the total heat transfer area C of the rotor passage 43a is set large based on the vessel cross-sectional area S. Therefore, as a result, the heat transfer area of ​​the rotor passage 43a is set large, similar to the above-mentioned condition 2. Therefore, in this condition 3 as well, similar to the above-mentioned condition 2, it is possible to cool the electric motor section 41, separate the lubricating oil 48 from the compressed gas mixture, and suppress and calm the propagation of the disproportionation reaction.

[0095] The above-mentioned condition 4 is a condition that the ratio (A+B) / S of the total cross-sectional area A+B of all the passages 43a, 44a, 44b to the container cross-sectional area S is 0.05 or more. This condition 4 sets the cross-sectional areas for all of the components consisting of the rotor passage 43a, the rotor outer passage, and the sealed container 31. In other words, this condition 4 differs from the above-mentioned conditions 1 to 3, and can be said to be a condition that specifies the lower limit of the total cross-sectional area of ​​all the passages provided in the electric motor section 41 based on the container cross-sectional area S.

[0096] According to this condition 4, the cross-sectional areas of the rotor passage 43a and all of the rotor outer passages in the electric motor section 41 are set relatively large. Therefore, similar to the above conditions 1 to 3, it is possible to satisfactorily cool the electric motor section 41 and separate the lubricating oil 48 from the compressed gas mixture.

[0097] Here, in Condition 4, unlike Conditions 1 to 3, the rotor passage 43a is not given priority, but the passages 43a, 44a, and 44b having a sufficient cross-sectional area are provided for the electric motor section 41. This ensures that the total cross-sectional area A of the rotor passage 43a is also large to a certain extent, making it difficult for the disproportionation reaction to propagate to the lower space 31b via the rotor passage 43a. As a result, the propagation of the disproportionation reaction can be suppressed and calmed down.

[0098] In addition, the compressor 30 according to the present disclosure may satisfy any one of the above-mentioned conditions 1 to 4, but may also satisfy two or more, three or more, or all four of these four conditions. This effectively suppresses or avoids the possibility of a large-scale disproportionation reaction occurring throughout the inside of the compressor 30, and further improves the reliability of the compressor 30.

[0099] Furthermore, in the compressor 30 according to the present disclosure, the working fluid for the refrigeration cycle used may contain a hydrofluoroolefin as a refrigerant component, but may further contain the above-mentioned disproportionation inhibitor. This not only enables the compressor 30 to suppress the propagation of the disproportionation reaction by satisfying any one of conditions 1 to 4, but also enables the disproportionation inhibitor to effectively suppress or mitigate the disproportionation reaction of the hydrofluoroolefin. This makes it more difficult for the disproportionation reaction to occur inside the compressor 30, thereby further improving the reliability of the compressor 30.

[0100] Furthermore, the working fluid for the refrigeration cycle used in the compressor 30 according to the present disclosure may contain, as a refrigerant component, the above-mentioned hydrofluorocarbon or another hydrofluoroolefin in addition to the hydrofluoroolefin. Typically, the working fluid for the refrigeration cycle may contain 1,1,2-trifluoroethylene as the hydrofluoroolefin and may contain difluoromethane as another refrigerant component. By using such a working fluid for the refrigeration cycle, the refrigeration cycle system including the compressor 30 can make the refrigeration cycle more efficient while reducing the impact on the environment. [Example of refrigeration cycle system configuration]

[0101] Next, an example of a refrigeration cycle system (refrigeration cycle device) according to the present disclosure, that is, a refrigeration cycle system including a compressor according to the present disclosure as described above, will be described with reference to Figures 2(A) and 2(B). The compressor according to the present disclosure uses the above-mentioned working medium for a refrigeration cycle (a working medium containing a hydrofluoroolefin in which a disproportionation reaction occurs as a refrigerant component), and therefore the refrigeration cycle system according to the present disclosure is also configured using the above-mentioned working medium for a refrigeration cycle.

[0102] The specific configuration of the refrigeration cycle system according to the present disclosure is not particularly limited, and may be any configuration in which components such as a compressor, a condenser, an expansion means, and an evaporator are connected by piping. Specific application examples of the refrigeration cycle system according to the present disclosure are also not particularly limited, and examples thereof include air conditioners (air conditioners), refrigerators (for home and commercial use), dehumidifiers, showcases, ice makers, heat pump water heaters, heat pump washing and drying machines, and vending machines.

[0103] An air conditioner will be described as a typical application example of the refrigeration cycle system according to the present disclosure. Specifically, as shown in the block diagram of Fig. 2(A), an air conditioner 10 according to this embodiment includes an indoor unit 11, an outdoor unit 12, and piping 13 connecting these. The indoor unit 11 includes a heat exchanger 14, and the outdoor unit 12 includes a heat exchanger 15, a compressor 30, and a pressure reducing device 16.

[0104] The heat exchanger 14 of the indoor unit 11 and the heat exchanger 15 of the outdoor unit 12 are connected in a ring shape by piping 13, thereby forming a refrigeration cycle. Specifically, the heat exchanger 14 of the indoor unit 11, the compressor 30, the heat exchanger 15 of the outdoor unit 12, and the pressure reducing device 16 are connected in a ring shape by piping 13 in this order. In addition, the piping 13 connecting the heat exchanger 14, the compressor 30, and the heat exchanger 15 is provided with a four-way valve 17 for switching between heating and cooling. The indoor unit 11 is provided with a blower fan, a temperature sensor, an operation unit, etc. (not shown), and the outdoor unit 12 is provided with a blower, an accumulator, etc. (not shown). Furthermore, the piping 13 is provided with various valve devices (including the four-way valve 17), a strainer, etc. (not shown).

[0105] The heat exchanger 14 provided in the indoor unit 11 exchanges heat between indoor air drawn into the indoor unit 11 by the blower fan and the refrigerant flowing inside the heat exchanger 14. During heating, the indoor unit 11 blows air warmed by heat exchange into the room, and during cooling, blows air cooled by heat exchange into the room. The heat exchanger 15 provided in the outdoor unit 12 exchanges heat between outside air drawn into the outdoor unit 12 by the blower and the refrigerant flowing inside the heat exchanger 15.

[0106] The specific configurations of the indoor unit 11 and the outdoor unit 12, or the specific configurations of the heat exchanger 14 or heat exchanger 15, compressor 30, pressure reducing device 16, four-way valve 17, blower fan, temperature sensor, operating unit, blower, accumulator, other valve devices, strainer, etc. are not particularly limited, and known configurations can be suitably used.

[0107] An example of the operation of the air conditioner 10 shown in FIG. 2(A) will be specifically described. First, in cooling operation or dehumidification operation, the compressor 30 of the outdoor unit 12 compresses and discharges the gas refrigerant, and the gas refrigerant is sent to the heat exchanger 15 of the outdoor unit 12 via the four-way valve 17. The heat exchanger 15 exchanges heat between the outside air and the gas refrigerant, so that the gas refrigerant condenses and becomes liquid. The liquefied liquid refrigerant is depressurized by the pressure reducing device 16 and sent to the heat exchanger 14 of the indoor unit 11. In the heat exchanger 14, the liquid refrigerant evaporates due to heat exchange with the indoor air, and becomes a gas refrigerant. This gas refrigerant returns to the compressor 30 of the outdoor unit 12 via the four-way valve 17. The compressor 30 compresses the gas refrigerant and discharges it again to the heat exchanger 15 via the four-way valve 17.

[0108] During heating operation, the compressor 30 of the outdoor unit 12 compresses and discharges the gas refrigerant, which is then sent to the heat exchanger 14 of the indoor unit 11 via the four-way valve 17. In the heat exchanger 14, the gas refrigerant condenses and liquefies due to heat exchange with the indoor air. The liquefied liquid refrigerant is depressurized by the decompression device 16 to become a two-phase gas-liquid refrigerant, and is sent to the heat exchanger 15 of the outdoor unit 12. Since the heat exchanger 15 exchanges heat between the outside air and the two-phase gas-liquid refrigerant, the two-phase gas-liquid refrigerant evaporates and becomes a gas refrigerant, which returns to the compressor 30. The compressor 30 compresses the gas refrigerant and discharges it again to the heat exchanger 14 of the indoor unit 11 via the four-way valve 17.

[0109] A refrigerator will be described as another typical application example of the refrigeration cycle system according to the present disclosure. Specifically, as shown in the block diagram of Fig. 2(B), a refrigerator 20 according to the present embodiment includes a compressor 30, a condenser 21, a pressure reducing device 22, an evaporator 23, and a pipe 24, etc., as shown in Fig. 1. The refrigerator 20 also includes a housing, a blower, an operation unit, a control unit, etc., which are not shown in the drawings, as a main body.

[0110] The compressor 30 compresses the refrigerant gas to produce a high-temperature, high-pressure gas refrigerant. The condenser 21 cools and liquefies the refrigerant. The pressure reducing device 22 is formed, for example, of a capillary tube, and reduces the pressure of the liquefied refrigerant (liquid refrigerant). The evaporator 23 evaporates the refrigerant to produce a low-temperature, low-pressure gas refrigerant. The compressor 30, the condenser 21, the pressure reducing device 22, and the evaporator 23 are connected in this order in a ring shape by piping 24 that circulates the refrigerant gas, thereby forming a refrigeration cycle.

[0111] The configurations of the compressor 30, the condenser 21, the pressure reducing device 22, the evaporator 23, the piping 24, the main body housing, the blower, the operation unit, the control unit, etc. are not particularly limited, and known configurations can be suitably used. The refrigerator 20 may also have other known configurations.

[0112] An example of the operation of the refrigerator 20 shown in Fig. 2(B) will be specifically described. The compressor 30 compresses the gas refrigerant and discharges it to the condenser 21. The condenser 21 cools the gas refrigerant to liquid refrigerant. The liquid refrigerant is reduced in pressure by passing through the pressure reducing device 22 and is sent to the evaporator 23. In the evaporator 23, the liquid refrigerant is evaporated by removing heat from the surroundings, and returns to the compressor 30 as gas refrigerant. The compressor 30 compresses the gas refrigerant and discharges it to the condenser 21 again.

[0113] In such a refrigeration cycle system, the compressor 30 satisfies at least one of the following conditions, as described above: [Condition 1] the total cross-sectional area A of the rotor passages 43a is equal to or greater than the total cross-sectional area B of the rotor outer passages (A≧B); [Condition 2] the total heat transfer area C of the rotor passages 43a is equal to or greater than the total heat transfer area D of the rotor outer passages (C≧D); [Condition 3] the ratio C / S of the total heat transfer area C of the rotor passages 43a to the container cross-sectional area S of the sealed container 31 is 1.0 or greater (C / S≧1.0); and [Condition 4] the ratio (A+B) / S of the total cross-sectional area A+B of all the passages 43a, 44a, 44b to the container cross-sectional area S is 0.05 or greater ((A+B) / S≧0.05).

[0114] This makes it possible to give predominance to the rotor passage 43a, which is relatively less likely to propagate the disproportionation reaction, among all the passages provided in the electric motor section 41 of the compressor 30. As a result, it is possible to effectively prevent the disproportionation reaction occurring in the upper space 31a or the lower space 31b of the electric motor section 41 from propagating to the opposite space.

[0115] Furthermore, by suppressing the propagation of the disproportionation reaction, the main function of the passages 43a, 44a, and 44b is to cool the motor unit 41, thereby making it possible to calm and eventually eliminate the disproportionation reaction itself. As a result, it is possible to effectively suppress or avoid the possibility of a large-scale disproportionation reaction occurring throughout the inside of the compressor 30. This makes it possible to further improve the reliability of the refrigeration cycle system including the compressor 30.

[0116] The present invention is not limited to the above-described embodiment, and various modifications are possible within the scope of the claims. The technical scope of the present invention also includes embodiments obtained by appropriately combining the technical means disclosed in different embodiments or multiple modified examples.

[0117] (Additional Note) Based on the above description of the embodiments, the following techniques are disclosed in this specification. (Technology 1) A compressor that uses a working fluid for a refrigeration cycle containing at least a hydrofluoroolefin as a refrigerant component, the compressor comprising: an electric motor unit having a rotor and a stator; a compression mechanism unit driven by the electric motor unit; and an airtight container that houses the electric motor unit and the compression mechanism unit, wherein spaces are provided above and below the electric motor unit within the airtight container, and the electric motor unit is provided with a plurality of passages that communicate the upper space with the lower space, wherein a total cross-sectional area of ​​all the passages provided in the rotor is A and a total cross-sectional area of ​​all the passages provided other than the rotor is B, where A is greater than or equal to B.

[0118] (Technology 2) A compressor that uses a working fluid for a refrigeration cycle containing at least a hydrofluoroolefin as a refrigerant component, the compressor comprising: an electric motor unit having a rotor and a stator; a compression mechanism unit driven by the electric motor unit; and an airtight container that houses the electric motor unit and the compression mechanism unit, wherein spaces are provided above and below the electric motor unit within the airtight container, and the electric motor unit is provided with a plurality of passages that communicate the upper space with the lower space, wherein a heat transfer area of ​​the passages is the product of an equivalent diameter d of the passages, a passage length L, and pi (π × d × L), where C is a total heat transfer area of ​​all the passages provided in the rotor, and D is a total heat transfer area of ​​all the passages provided other than the rotor, and C is greater than or equal to D.

[0119] (Technology 3) A compressor using a working fluid for a refrigeration cycle containing at least a hydrofluoroolefin as a refrigerant component, the compressor comprising: an electric motor unit having a rotor and a stator; a compression mechanism unit driven by the electric motor unit; and a sealed container accommodating the electric motor unit and the compression mechanism unit therein; within the sealed container, spaces are provided above and below the electric motor unit; the electric motor unit is provided with a plurality of passages communicating the upper space with the lower space; a heat transfer area of ​​the passage is defined as the product of an equivalent diameter d of the passage, a passage length L and pi (π × d × L), a total heat transfer area of ​​all the passages provided in the rotor is defined as C, and a cross-sectional area of ​​the sealed container based on an inner diameter of the sealed container is defined as S, whereby a ratio C / S of the total heat transfer area C to the cross-sectional area S is 1.0 or more (C / S≧1.0).

[0120] (Technology 4) A compressor using a working fluid for a refrigeration cycle containing at least a hydrofluoroolefin as a refrigerant component, the compressor comprising: an electric motor unit having a rotor and a stator; a compression mechanism unit driven by the electric motor unit; and a sealed container accommodating the electric motor unit and the compression mechanism unit therein; within the sealed container, spaces are provided above and below the electric motor unit; the electric motor unit is provided with a plurality of passages communicating the upper space with the lower space; among the passages, a total cross-sectional area of ​​all the passages provided in the rotor is A, a total cross-sectional area of ​​all the passages provided other than the rotor is B, and further, a cross-sectional area of ​​the sealed container based on an inner diameter of the sealed container is S, whereby a ratio (A+B) of the total cross-sectional area of ​​all the passages to the cross-sectional area S of the sealed container is 0.05 or more ((A+B) / S≧0.05).

[0121] (Technology 5) The compressor according to any one of Technologies 1 to 4, wherein the passage provided other than the rotor is at least one of an air gap passage formed between the rotor and the stator and a stator passage provided between the stator and the sealed container.

[0122] (Technology 6) The compressor according to any one of Techniques 1 to 5, wherein the hydrofluoroolefin is at least one of 1,1,2-trifluoroethylene (HFO1123) and 1,2-difluoroethylene (HFO1132).

[0123] (Technology 7) The compressor according to any one of Techniques 1 to 6, wherein the working fluid for a refrigeration cycle further contains difluoromethane as a refrigerant component and at least one of saturated hydrocarbons, haloalkanes, and fluoroalkanes having 1 to 3 carbon atoms and a boiling point of 0°C or lower (excluding difluoromethane) as a disproportionation inhibitor.

[0124] (Technology 8) A refrigeration cycle system using a working fluid for a refrigeration cycle containing at least a hydrofluoroolefin as a refrigerant component, and comprising the compressor according to any one of Technologies 1 to 7. [Industrial Applicability]

[0125] The present invention can be suitably used in the field of compressors that use hydrofluoroolefins (HFOs) as a refrigerant component, and can also be suitably used widely in the field of refrigeration cycle systems equipped with the compressor, such as air conditioners, refrigerators (for home and commercial use), dehumidifiers, showcases, ice makers, heat pump water heaters, heat pump washer-dryers, vending machines, and the like. [Explanation of symbols]

[0126] 10: Air conditioning equipment (refrigeration cycle system) 11: Indoor unit 12:Outdoor unit 13:Plumbing 14:Heat exchanger 15: Heat exchanger 16: Pressure reducing device 17: Four-way valve 20: Refrigerator (freezing cycle system) 21: Condenser 22: Pressure reducing device 23: Evaporator 24: Piping 30: Compressor (rotary type) 31: Airtight container 31a: Upper space 31b: Downward space 32: Upper shell 33: Body shell 34: Lower shell 35:Discharge pipe 36: Suction pipe 41: Electric motor section (motor) 42: Compression mechanism 43: Rota 43a: rotor passage 44:Stator 44a: Stator passage (outer rotor passage) 44b: Air gap passage (outside rotor passage) 45: Shaft 46: Piston 47: Cylinder 48: Lubricating oil

Claims

1. A compressor using a working fluid for a refrigeration cycle containing at least a hydrofluoroolefin as a refrigerant component, an electric motor section having a rotor and a stator; a compression mechanism unit driven by the electric motor unit; a sealed container that houses the electric motor unit and the compression mechanism unit therein, The sealed container has spaces above and below the electric motor unit, The electric motor unit is provided with a plurality of passages that communicate with the upper space and the lower space, wherein, among the passages, a total cross-sectional area of ​​all the passages provided in the rotor is A, and a total cross-sectional area of ​​all the passages provided other than the rotor is B, and A≧B is satisfied. Compressor.

2. A compressor using a working fluid for a refrigeration cycle containing at least a hydrofluoroolefin as a refrigerant component, an electric motor section having a rotor and a stator; a compression mechanism unit driven by the electric motor unit; a sealed container that houses the electric motor unit and the compression mechanism unit therein, The sealed container has spaces above and below the electric motor unit, The electric motor unit is provided with a plurality of passages that communicate with the upper space and the lower space, wherein a heat transfer area of ​​the passage is a product (π×d×L) of an equivalent diameter d of the passage, a passage length L, and pi, and a total heat transfer area of ​​all the passages provided in the rotor is C, and a total heat transfer area of ​​all the passages provided other than the rotor is D, and C≧D is satisfied. Compressor.

3. A compressor using a working fluid for a refrigeration cycle containing at least a hydrofluoroolefin as a refrigerant component, an electric motor section having a rotor and a stator; a compression mechanism unit driven by the electric motor unit; a sealed container that houses the electric motor unit and the compression mechanism unit therein, The sealed container has spaces above and below the electric motor unit, The electric motor unit is provided with a plurality of passages that communicate with the upper space and the lower space, When the heat transfer area of ​​the passage is the product of the equivalent diameter d of the passage, the passage length L, and pi (π×d×L), the total heat transfer area of ​​all the passages provided in the rotor is C, and the cross-sectional area of ​​the sealed container based on the inner diameter of the sealed container is S, The ratio C / S of the total heat transfer area C to the cross-sectional area S is 1.0 or more (C / S≧1.0), Compressor.

4. A compressor using a working fluid for a refrigeration cycle containing at least a hydrofluoroolefin as a refrigerant component, an electric motor section having a rotor and a stator; a compression mechanism unit driven by the electric motor unit; a sealed container that houses the electric motor unit and the compression mechanism unit therein, The sealed container has spaces above and below the electric motor unit, The electric motor unit is provided with a plurality of passages that communicate with the upper space and the lower space, Among the passages, the total cross-sectional area of ​​all the passages provided in the rotor is A, the total cross-sectional area of ​​all the passages provided other than the rotor is B, and further, the cross-sectional area of ​​the sealed container based on the inner diameter of the sealed container is S. The ratio (A+B) / S of the total cross-sectional area (A+B) of all the passages to the cross-sectional area S of the sealed container is 0.05 or more ((A+B) / S≧0.05). Compressor.

5. The passage provided outside the rotor is an air gap passage formed between the rotor and the stator; and A stator passage provided between the stator and the sealed container At least one of A compressor according to any one of claims 1 to 4.

6. The hydrofluoroolefin is at least one of 1,1,2-trifluoroethylene (HFO1123) and 1,2-difluoroethylene (HFO1132); A compressor according to any one of claims 1 to 4.

7. The working fluid for a refrigeration cycle further contains difluoromethane as a refrigerant component, The disproportionation inhibitor contains at least one of a saturated hydrocarbon, a haloalkane, and a fluoroalkane having 1 to 3 carbon atoms and a boiling point of 0° C. or less (excluding difluoromethane). A compressor according to any one of claims 1 to 4.

8. The refrigeration cycle working fluid contains at least a hydrofluoroolefin as a refrigerant component, A compressor comprising the compressor according to any one of claims 1 to 4. Refrigeration cycle system.

Images