JP7453480B1 - Refrigeration cycle equipment and compressor - Google Patents

Abstract

A refrigeration cycle device comprising a refrigerant, a compressor that compresses the refrigerant, and refrigeration oil that lubricates sliding parts of the compressor, the refrigerant comprising a first refrigerant and a second refrigerant. The first refrigerant is a hydrofluoroolefin refrigerant, the second refrigerant is a halogenated hydrocarbon containing at least one element selected from the group consisting of chlorine, bromine, and iodine, and the refrigerating machine oil contains one or both of a first compound and a second compound, the first compound contains a first alkyl group having at least one tertiary carbon, and the second compound contains an oxygen atom and a first alkyl group having at least one tertiary carbon. a secondary alkyl group having a primary carbon or a secondary carbon adjacent to the atom.

Description

The present disclosure relates to a refrigeration cycle device and a compressor.

In order to prevent global warming, various measures against climate change have been reported internationally. In order to comply with refrigerant regulations such as the Montreal Protocol, efforts are being made to commercialize low GWP refrigerants.

Regarding the refrigerant used in refrigeration cycle equipment, progress is being made to replace R-410A, which has traditionally been mainly used, with a refrigerant that has a lower global warming potential (GWP) than R-410A. Note that R-410A is a mixed refrigerant in which 50% by mass of R-32 (difluoromethane) and 50% by mass of R-125 (pentafluoroethane) are mixed, and the GWP of R-410A is 2088. .

Examples of low GWP refrigerant compositions that can replace R-410A include mildly flammable (Class 2L in ANSI/ASHRAE Standard 34-2019) such as R-32 (GWP = 675) and R-1234yf (GWP < 1). ) refrigerant, highly flammable (Class 3 in ANSI/ASHRAE Standard 34-2019) refrigerant such as R-290 (GWP=3).

In addition to having a low GWP, it is desirable that the refrigerant has low flammability from the viewpoint of safety. R-466A, a refrigerant announced in June 2018, has a GWP of 733, which is lower than R-410A, and is classified as non-flammable (Class 1) in ANSI/ASHRAE Standard 34-2019. )are categorized.

R-466A is a combination of R-32 (difluoromethane, GWP=675), R-125 (pentafluoroethane, GWP=3500) and R-13I1 (trifluoroiodomethane, CF ₃ I, GWP=0.5). It is a mixed refrigerant. The mixing ratios of R-32, R-125 and R-13I1 are 49.0% by mass (compositional tolerance: +0.5/-2.0) and 11.5% by mass (compositional tolerance: +2.0/- 0.5) and 39.5% by mass (compositional tolerance: +2.0/-0.5).

Patent Document 1 (JP 2020-034260A) and Patent Document 2 (JP 2020-034261A) disclose refrigeration cycle devices using R-466A as a refrigerant.

In order to satisfy all of the required characteristics of a refrigerant, such as low flammability, low GWP, and good cooling performance, it is preferable to combine a nonflammable, low GWP refrigerant with a low GWP and high cooling performance refrigerant.

Nonflammable and low GWP refrigerants include halogenated hydrocarbons such as R-13I1 in which halogens other than fluorine are bonded. The above-mentioned R-466A uses R-13I1, but since the GWP of R-32 and R-125 is large, the GWP of R-466A is 733.

In order to further reduce the GWP of a mixed refrigerant containing R-13I1, it is preferable to mix R-13I1 with a refrigerant having a smaller GWP and higher cooling performance. Examples of refrigerants with low GWP and high cooling performance include HFO (hydrofluoroolefin) refrigerants.

Patent Document 3 (Japanese Patent Publication No. 2010-509489) discloses a refrigerant that is a mixture of hydrofluoroalkene and iodocarbon. Here, the hydrofluoroalkene is an HFO-based refrigerant, and the iodocarbon is R-13I1.

JP2020-034260A JP2020-034261A Special Publication No. 2010-509489

Halogens other than fluorine, specifically halogenated hydrocarbons in which at least one of chlorine, bromine, and iodine is bonded, are not suitable for use in refrigeration cycle equipment because the chemical bond between the halogen and carbon is thermally unstable. Under the associated high temperature conditions, radicals are generated. The radical becomes a polymerization initiator for the HFO refrigerant. Therefore, in a mixed refrigerant containing a halogenated hydrocarbon bonded with a halogen other than fluorine and an HFO-based refrigerant, radical polymerization of the HFO-based refrigerant may proceed as the refrigeration cycle device is used. As radical polymerization of the HFO-based refrigerant progresses, it becomes sludge, which may clog refrigerant piping and reduce the reliability of the refrigeration cycle device.

In view of the above-mentioned problems, the present disclosure provides a refrigeration cycle device and a compressor that can ensure reliability even when using a mixed refrigerant containing a halogenated hydrocarbon bonded with a halogen other than fluorine and an HFO-based refrigerant. The purpose is to provide.

The refrigeration cycle device according to the present disclosure includes:
refrigerant and
a compressor that compresses the refrigerant;
A refrigeration cycle device comprising: refrigeration oil that lubricates sliding parts of the compressor,
The refrigerant includes a first refrigerant and a second refrigerant,
The first refrigerant is a hydrofluoroolefin refrigerant,
The second refrigerant is a halogenated hydrocarbon containing at least one element selected from the group consisting of chlorine, bromine, and iodine,
The refrigeration oil contains one or both of a first compound and a second compound,
The first compound includes a first alkyl group having at least one tertiary carbon,
The second compound is a refrigeration cycle device that includes an oxygen atom and a second alkyl group having a primary carbon or a secondary carbon adjacent to the oxygen atom.

The refrigeration cycle device according to the present disclosure includes:
refrigerant and
a compressor that compresses the refrigerant;
Refrigerating machine oil that lubricates the sliding parts of the compressor;
A refrigeration cycle device comprising: a refrigerant pipe through which the refrigerant passes;
The refrigerant includes a first refrigerant and a third refrigerant,
The first refrigerant is a hydrofluoroolefin refrigerant,
The third refrigerant is a refrigerant containing at least one element selected from the group consisting of chlorine, bromine, and iodine,
The refrigeration oil contains one or both of a first compound and a second compound,
The first compound includes a first alkyl group having at least one tertiary carbon,
The second compound includes an oxygen atom and a second alkyl group having a primary carbon or a secondary carbon adjacent to the oxygen atom,
One or both of the compressor and the refrigerant piping is a refrigeration cycle in which one or both of the existing compressor and the existing refrigerant piping are reused in a refrigeration cycle device that has a history of using the third refrigerant. It is a device.

The compressor according to the present disclosure includes:
A compressor used in a refrigeration cycle device,
The refrigeration cycle device includes:
refrigerant and
a compressor that compresses the refrigerant;
Refrigerating machine oil that lubricates the sliding parts of the compressor,
The refrigerant includes a first refrigerant and a second refrigerant,
The first refrigerant is a hydrofluoroolefin refrigerant,
The second refrigerant is a halogenated hydrocarbon containing at least one element selected from the group consisting of chlorine, bromine, and iodine,
The refrigeration oil contains one or both of a first compound and a second compound,
The first compound includes a first alkyl group having at least one tertiary carbon,
The second compound is a compressor that includes an oxygen atom and a second alkyl group having a primary carbon or a secondary carbon adjacent to the oxygen atom.

The compressor according to the present disclosure includes:
A compressor used in a refrigeration cycle device,
The refrigeration cycle device includes:
refrigerant and
a compressor that compresses the refrigerant;
Refrigerating machine oil that lubricates the sliding parts of the compressor;
A refrigerant pipe through which the refrigerant passes,
The refrigerant includes a first refrigerant and a third refrigerant,
The first refrigerant is a hydrofluoroolefin refrigerant,
The third refrigerant is a refrigerant containing at least one element selected from the group consisting of chlorine, bromine, and iodine,
The refrigeration oil contains one or both of a first compound and a second compound,
The first compound includes a first alkyl group having at least one tertiary carbon,
The second compound includes an oxygen atom and a second alkyl group having a primary carbon or a secondary carbon adjacent to the oxygen atom,
One or both of the compressor and the refrigerant piping is a compressor that reuses an existing compressor and existing refrigerant piping in a refrigeration cycle device that has a history of using the third refrigerant.

According to the present disclosure, it is possible to provide a refrigeration cycle device and a compressor that can ensure reliability even when a mixed refrigerant containing a halogenated hydrocarbon bonded with a halogen other than fluorine and an HFO-based refrigerant is used. It is possible.

FIG. 1 is a configuration diagram of a refrigeration cycle device according to an embodiment. FIG. 2 is a cross-sectional view showing a cross section parallel to the axial direction of the main shaft of the motor of the compressor according to the embodiment. FIG. 3 is a cross-sectional view showing the AA cross section in FIG. 2 of a rotor included in the compressor according to the embodiment. FIG. 4 is a sectional view showing the BB cross section in FIG. 3 of a magnet included in the compressor according to the embodiment.

First, in order to deepen the understanding of the present disclosure, when a mixed refrigerant containing a halogenated hydrocarbon bonded with a halogen other than fluorine and an HFO refrigerant is used, the radical polymerization of the HFO refrigerant that occurs in the mixed refrigerant will be explained. explain. In the following, a case will be described in which R-13I1 is used as a halogenated hydrocarbon to which a halogen other than fluorine is bonded.

Since the C--I bond of R-13I1 has a low bond energy, the bond is easily broken, and radicals (CF3.) are easily generated. Particularly when the magnet 44 is a neodymium magnet or when the refrigeration cycle device includes parts made of brass, the bond is more likely to break when R-13I1 comes into contact with the neodymium magnet or parts made of brass. The decomposition of R-13I1 when it comes into contact with a neodymium magnet is shown by the following reaction formula (1).

The radicals (CF ₃ .) generated in the above reaction formula (1) act as a radical polymerization initiator for the HFO-based refrigerant containing multiple bonds. The CF ₃ radical has a small molecular size and can easily approach double bonds, so it is easy to polymerize refrigerants containing double bonds. Radical polymerization caused by a radical (CF ₃ .) and a refrigerant containing a double bond is shown by the following reaction formula (2).

In the above reaction formula (2), R ₁ , R ₂ and R ₃ each represent an alkyl group, fluorine or hydrogen.

Radical polymerization is a reaction similar to radical polymerization when synthesizing polyethylene and the like. Free radicals that initiate polymerization are generated, and the free radicals react with molecules containing double bonds, thereby converting the molecules containing double bonds into radicals. The radicalized molecule reacts with another molecule containing a double bond, increasing the chain length. Eventually, the radicals react with each other and the polymerization reaction stops. It is assumed that the series of reactions proceeds mainly in the sliding parts and the refrigerant discharge part of the compressor, which are exposed to high temperatures.

As a result of the progress of the radical polymerization described above, the refrigerant containing double bonds becomes a fluororesin-like compound. Fluororesin is extremely stable and has low solubility, so it does not dissolve in refrigerator oil or refrigerant. Therefore, there is a problem that the fluororesin-like compound produced by radical polymerization turns into sludge, which blocks the refrigerant pipes and reduces the reliability of the refrigeration cycle. Such a problem is a new problem discovered by the present inventors.

As a result of intensive studies to solve the above problems, the present inventors have found that when using a mixed refrigerant containing a halogenated hydrocarbon bonded with a halogen other than fluorine and an HFO-based refrigerant, a specific refrigerating machine oil It has been newly discovered that by using refrigeration cycle equipment and a compressor, radical polymerization of HFO-based refrigerants can be suppressed and reliability can be ensured.

Below, a refrigeration cycle device and a compressor according to an embodiment of the present disclosure will be described based on the drawings. Note that the present disclosure is not limited to the following embodiments, and may be modified or omitted without departing from the spirit of the present disclosure. In addition, common elements in each figure are given the same reference numerals, and redundant explanations will be omitted.

Embodiment 1.
<Refrigerating cycle equipment>
FIG. 1 is a configuration diagram of a refrigeration cycle device according to a first embodiment.

As shown in FIG. 1, the refrigeration cycle device of this embodiment includes a compressor 1, a condenser 2, an expansion valve 3, and an evaporator 4. These are connected by refrigerant pipes 5a to 5d to form a refrigerant circuit 5.

A gaseous refrigerant flows through the refrigerant circuit 5, and the refrigerant is compressed by the compressor 1. In the condenser 2, the gaseous refrigerant compressed by the compressor 1 is cooled and becomes a high-pressure liquid refrigerant or a gas-liquid two-phase refrigerant. In the expansion valve 3, the pressure of the high-pressure liquid refrigerant or the gas-liquid two-phase refrigerant is reduced. In the evaporator 4, the depressurized refrigerant is heated and becomes a low-pressure gaseous refrigerant. The compressor 1 sucks the refrigerant that has been turned into a low-pressure gas by the evaporator 4 and compresses it again. In this way, the refrigerant circulates within the refrigerant circuit 5 of the refrigeration cycle device 100.

The condenser blower 6 is a component that sends air to the condenser 2, and is provided to promote the refrigerant flowing into the condenser 2 to exchange heat with the air and absorb or release heat. The evaporator blower 7 is a component that sends air to the evaporator 4, and is provided to promote the refrigerant flowing into the evaporator 4 to absorb or release heat by exchanging heat with the air.

The refrigeration cycle device may be, for example, a device that can perform both cooling and heating, a device that can only perform cooling, or a device that can only perform heating, and can be applied to various types of refrigeration and air conditioning equipment. It is possible.

FIG. 2 is a sectional view showing an example of the compressor of the refrigeration cycle device according to the present embodiment. As shown in FIG. 2 , the compressor (electric refrigerant compressor) 200 includes a shell 8 . The shell includes a compression mechanism 9 inside, and is connected to a suction pipe 10 for allowing the refrigerant to flow into the inside and a discharge pipe 11 for causing the refrigerant to flow outside. The compression mechanism 9 is configured to compress the refrigerant entering the shell 8 from the suction pipe 10 and discharge it from the discharge pipe 11.

The compressor 1 includes a motor section having a shaft 12, a rotor 17, and a stator 18. The compression mechanism 9 is driven by this motor section. Refrigerating machine oil (lubricating oil) for lubricating the sliding parts of the compression mechanism 9 and the motor section is stored in the oil reservoir section 13 .

FIG. 3 is a sectional view showing the AA cross section in FIG. 2 of the rotor included in the compressor according to the embodiment. As shown in FIG. 3, the rotor 17 includes a rotor core 43 and a plurality of magnets 44.

The rotor core 43 is formed by laminating a plurality of disc-shaped steel plates. Further, a plurality of magnet insertion holes 43a, a plurality of coolant passage holes 43b, and a shaft hole 43c are formed in the rotor core 43 so as to penetrate in the lamination direction of the steel plates. A magnet 44 is inserted into the magnet insertion hole 43a.

The refrigerant passage hole 43b is a hole through which the refrigerant compressed by the compression mechanism 9 passes, and after passing through the refrigerant, the refrigerant is discharged to the refrigerant pipe 5a via the discharge pipe 11. The shaft 12 is inserted into the shaft hole 43c.

FIG. 4 is a sectional view showing the BB cross section in FIG. 3 of the magnet 44 according to the embodiment. As shown in FIG. 4, a coating 45 is preferably provided on the surface of the magnet 44. The film 45 is formed to cover the entire surface of the magnet 44. In FIG. 4, the surface of the magnet 44 on the front side of the paper and the surface of the magnet 44 on the back side of the paper are also covered with the film 45. The thickness of the film 45 is not particularly limited, and for example, the film 45 is formed with a thickness of 100 μm or less.

More preferably, the film 45 is an inorganic film with excellent heat resistance and oil resistance. The film 45 preferably contains at least aluminum (Al) and silicon (Si), and more preferably contains aluminum (Al), silicon (Si), and magnesium (Mg). Note that it is more preferable that the film 45 does not contain phosphorus (P). Since the coating 45 can prevent contact between the refrigerant and the magnet (especially neodymium magnet), it is possible to prevent the decomposition of the refrigerant bonded with halogen other than fluorine due to contact between the refrigerant and the magnet. However, since the film 45 is not formed uniformly in some places and a portion of the magnet 44 is exposed, it is difficult to completely prevent the decomposition of the refrigerant.

The method for forming the film 45 on the magnet 44 is not particularly limited, and any existing film forming method can be used. For example, sputtering, chemical vapor deposition (CVD), vapor deposition, ion plating, ion beam deposition, dip coating, spin coating, spray coating, plating, and other methods can be selected as appropriate.

The stator 18 (FIG. 2) includes, for example, an insulating film made of polyester. Here, as the polyester, for example, polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene naphthalate (PEN), polybutylene naphthalate (PBN), polytrimethylene terephthalate (PTT), poly-1,4 - Cyclohexane dimethylene terephthalate (PCT), or copolymers or composite materials thereof.

In this embodiment, refrigeration cycle device 100 includes a refrigerant and a compressor that compresses the refrigerant. The compressor includes refrigerating machine oil that lubricates the sliding parts of the compressor. The refrigerant and refrigerating machine oil will be explained below.

<Refrigerant>
The refrigerant used in this embodiment includes a first refrigerant and a second refrigerant. The first refrigerant is a hydrofluoroolefin (HFO) refrigerant. The second refrigerant is a halogenated hydrocarbon containing at least one element selected from the group consisting of chlorine, bromine, and iodine.

Examples of the HFO-based refrigerant that is the first refrigerant include hydrofluoroethylene such as HFO-1141, R-1132a, HFO-1132 (E), HFO-1132 (Z), and HFO-1123, HFO-1225ye (Z), and HFO. -1225ye (E), HFO-1225zc, R-1234yf, R-1234ze (E), HFO-1234ze (Z), HFO-1234ye (Z), HFO-1234ye (E), HFO-1243zf, HFO-1252zf, Hydrofluoropropylene such as HFO-1261yf, R-1336mzz (E), R-1336mzz (Z), HFO-1336ze (Z), HFO-1336ze (E), HFO-1336yf, HFO-1336pyy, HFO-1327c ze,HFO -1327et, HFO-1327, HFO-1345czf, HFO-1345fyc, HFO-1345cye, HFO-1345cyf, HFO-1345eye, HFO-1345pyz, HFO-1345pyy (E), HFO-1345pyy (Z ), HFO-1345zy (E ), hydrofluorobutenes such as HFO-1345zy(Z), and perfluoroolefins such as PFO-1216.

From the viewpoint of making the refrigerant a mixed refrigerant having an operating pressure close to R-410A, the first refrigerant is preferably hydrofluoroethylene or hydrofluoropropylene. Among them, the first refrigerant is R-1132a, HFO-1132 (E), HFO-1132 (Z), HFO-1123, HFO-1225ye (Z), HFO-1225ye (E), HFO-1225zc, R-1234yf. , R-1234ze (E), HFO-1234ze (Z), HFO-1234ye (Z), HFO-1234ye (E), and HFO-1243zf are more preferred.

Examples of the second refrigerant, a halogenated hydrocarbon containing at least one element selected from the group consisting of chlorine, bromine, and iodine, include R-13I1, R-1130 (E), R-1224yd (Z), and , R-1233zd(E) and the like. Among them, it is preferable that the second refrigerant is R-13I1. R-13I1 has an extremely low GWP of 0.4, and is classified as non-flammable (Class 1) in ANSI/ASHRAE Standard 34-2019. Therefore, refrigerants containing R-13I1 can have low GWP and low flammability. Since hydrochlorofluoropropylenes such as R-1224yd (Z) and R-1233zd (E) contain chlorine, they may be polymerized only with these refrigerants.

In addition to the first refrigerant and the second refrigerant, the refrigerant used in this embodiment may further include an HFC refrigerant. Examples of HFC refrigerants include HFC-23, HFC-32, HFC-41, HFC-125, HFC-134, HFC-134a, HFC-143, HFC-143a, HFC-152, HFC-152a, HFC-161, etc. can be mentioned. Refrigerants can also include halogen-free refrigerants, such as propane, isobutane, and carbon dioxide.

In the refrigerant used in this embodiment, the content rate of the first refrigerant and the content rate of the second refrigerant can be appropriately set in consideration of the balance between GWP and cooling performance.

The GWP of the refrigerant used in this embodiment is preferably 750 or less. A refrigerant with a GWP of 750 or less is a refrigerant with excellent environmental performance and is highly compliant with legal regulations. Further, a refrigerant having a GWP of 750 or less can be used not only in a refrigerator but also in an air conditioner as a refrigeration cycle device. For GWP, the value (100-year value) of the Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report (AR5) is used. Further, for the GWP of a refrigerant not described in AR5, a value described in other known documents may be used, or a value calculated or measured using a known method may be used.

The refrigerant used in this embodiment is preferably a refrigerant whose flammability is classified as nonflammable in ANSI/ASHRAE Standard 34-2019. Refrigerants classified as non-flammable require means, equipment, or structure for diffusing refrigerant leaked into the refrigeration cycle equipment, a sensor for detecting refrigerant leakage, and an alarm device that issues an alarm when the sensor detects refrigerant leakage. There is no need to provide Furthermore, refrigerants classified as non-flammable can be used even in areas where the use of flammable refrigerants is not permitted by legal regulations.

<Refrigerating machine oil>
The refrigeration oil used in this embodiment includes one or both of the first compound and the second compound. The first compound includes a first alkyl group having at least one tertiary carbon. The second compound includes an oxygen atom and a second alkyl group having a primary carbon or a secondary carbon adjacent to the oxygen atom. In Embodiment 1, a case where the refrigerating machine oil contains the first compound will be described.

The first compound will be explained. Tertiary carbon means carbon in which three of the four bonds of carbon are bonded to carbon. The remaining one is generally bonded to hydrogen. Examples of the first compound include ester oils and ether oils. For example, in the ester oil having the structure shown below, the carbon at the β position corresponds to the tertiary carbon. In the following formula, R ₄ , R ₅ and R ₆ are each an alkyl group or hydrogen.

Examples of the primary alkyl group having at least one tertiary carbon include isobutyl group, sec-butyl group, cyclobutyl group, isopropyl group, 2-methylhexyl group, 2-ethylpentyl group, 2-ethylhexyl group, 3,5 , 5-trimethylhexyl group and the like.

The first compound may be a polyol ester, which is an ester of a diol or polyol and a fatty acid. These polyol esters may be used alone or in combination of two or more.

When the first compound is a polyol ester, the fatty acids used in the synthesis of the polyol ester include isobutyric acid, 2-methylhexanoic acid, 2-ethylpentanoic acid, 2-ethylhexanoic acid, 3,5,5-trimethylhexane. Acids etc. fall under this category. The fatty acid used for synthesis may further contain a straight chain fatty acid as long as it contains these fatty acids.

When the first compound is a polyol ester, the diol or polyol used to synthesize the polyol ester includes a diol such as neopentyl glycol, trimethylolethane, trimethylolpropane, trimethylolbutane, di-(trimethylolpropane), Polyols such as tri-(trimethylolpropane), pentaerythritol, di-(pentaerythritol), and tri-(pentaerythritol) are preferred.

When the first compound is a polyol ester, examples of the first alkyl group include isopropyl group, 2-methylhexyl group, 2-ethylpentyl group, 2-ethylhexyl group, and 3,5,5-trimethylhexyl group.

The first compound may be an ethereal oil. As an ether oil, a typical structure of polyvinyl ether is shown below. In the ether oil having this structure, R ₁ , R ₂ , R ₃ and R ₄ correspond to alkyl groups.

When the alkyl group contains a tertiary carbon, the alkyl group is an isobutyl group, a sec-butyl group, a cyclobutyl group, or an isopropyl group.

The first compound may be a polyvinyl ether. These polyvinyl ethers may be used alone or in combination of two or more.

When the first compound is polyvinyl ether, the first alkyl group is preferably an isobutyl group, a sec-butyl group, a cyclobutyl group, or an isopropyl group.

The first compound may be a polyalkylene glycol. A preferable example of the polyalkylene glycol is a compound having a homopolymer chain of propylene oxide or a copolymer chain of propylene oxide and ethylene oxide, and at least one of both ends thereof is blocked with an ether bond, and the blocked ether Examples include cases where the alkyl group bonded to the bond contains a tertiary carbon. Examples of the alkyl group containing a tertiary carbon include isopropyl group, isobutyl group, secbutyl group, and cyclobutyl group.

When the first compound is a polyalkylene glycol, the polyalkylene glycol is preferably polypropylene glycol with both ends blocked.

In the above structural formula of polyvinyl ether, when hydrogen instead of an alkyl group is present at either position of R ₁ or R ₂ , the carbon bonded to R ₁ and R ₂ becomes a tertiary carbon. In this way, the main chain may contain tertiary carbon.

The refrigerating machine oil used in this embodiment can contain the first compound. In this case, the content of the first compound in the refrigerating machine oil can be appropriately set in consideration of compatibility with the refrigerant.

The mechanism by which radical polymerization can be suppressed when a first compound containing a first alkyl group having at least one tertiary carbon is used as the refrigerating machine oil will be described below. When an ester oil having a tertiary carbon at the β-position of the alkyl group is used as the first compound, the _CF3 radical extracts a hydrogen atom from the first compound, as shown in reaction formula (3) below. .

When there is a tertiary carbon at the β position, hydrogen atoms bonded to the carbon atom at the α position, hydrogen atoms bonded to the carbon atom at the β _position , and hydrogen atoms bonded to the carbon atom at the γ position due to the CF3 radical. The ease of abstraction of is explained using the enthalpy of reaction. Here, the carbon atoms at the α-position and the γ-position are both secondary carbons.

As a result of molecular orbital calculation, the enthalpy change of the reaction when a hydrogen atom is extracted at the α position is -45 KJ/mol. The enthalpy change of the reaction when a hydrogen atom is extracted at the β position is -63 KJ/mol. The enthalpy change of the reaction when a hydrogen atom is extracted at the γ position is -32 KJ/mol. It is confirmed that the enthalpy change in the β position is extremely large. Therefore, when the ester oil contains tertiary carbon, the hydrogen atom selectively bonded to the carbon atom at the β position is donated to the CF ₃ radical to become CF ₃ H, resulting in radical polymerization of the CF ₃ radical. It is presumed that the function as an initiator disappears, and the polymerization of the HFO-based refrigerant containing double bonds is suppressed.

Further, since the radicals derived from the refrigerating machine oil (first compound) generated by the extraction of hydrogen atoms from the first compound have a large molecular size, it is presumed that they do not contribute to the polymerization of the HFO-based refrigerant. Note that the radicals derived from the refrigerating machine oil (first compound) may extract hydrogen from the nearby refrigerating machine oil. However, the radicals derived from the refrigerating machine oil generated in this way do not have low solubility in the refrigerating machine oil etc. unlike fluororesins. Therefore, even if such radicals derived from refrigeration oil exist, their influence on the reliability of the refrigeration cycle is small.

The present invention provides a refrigeration cycle device and a compressor that can suppress radical polymerization and ensure reliability by using a first compound containing a first alkyl group having at least one tertiary carbon as the refrigeration oil. This is a new finding discovered by the inventors. In addition, Patent Document 3 (Japanese Patent Application Publication No. 2010-509489) states that in order to suppress the decomposition of R-13I1, the total number of hydrogen atoms that have at least one hydrogen atom and at least one carbon atom and are bonded to a carbon atom is It is disclosed to select at least one lubricant having no more than 17% tertiary hydrogen atoms. Further, Patent Document 3 states that decomposition of the refrigerant can be suppressed by selecting a lubricant having a small amount of tertiary hydrogen atoms (paragraph 0006 of the specification). Since hydrogen is a monovalent atom, there are no tertiary hydrogens. Therefore, the lubricant used in Patent Document 3 is unknown. Note that tertiary hydrogen is a misprint, and if it is correctly interpreted as tertiary carbon, Patent Document 3 states that by selecting a lubricant having a small amount of tertiary hydrogen atoms, the refrigerant is stabilized. It shows you what to do. Such a technical idea of Patent Document 3 is to suppress radical polymerization of the refrigerant and stabilize the refrigerant by using a first compound containing a primary alkyl group having at least one tertiary carbon as the refrigerating machine oil. This is completely contrary to the technical idea of the present invention, which is to make it possible to

Refrigerating machine oil can contain other base oils and additives in addition to one or both of the first compound and the second compound.

The type of base oil is not particularly limited, but examples include polyol ester oil, polyvinyl ether oil, polyalkylene glycol oil, alkylbenzene oil, alkylnaphthalene oil, mineral oil, polyα-olefin oil, or mixtures thereof. It is desirable to control the moisture content of refrigeration oil. In particular, it is desirable to control the moisture content of ester oil, polyvinyl ether oil, and polyalkylene glycol oil to 600 ppm or less. This is because these refrigerating machine oils are polar and tend to contain water. If the amount of water is large, there is a risk that PET or the like used in the stator 18 (FIG. 2) may be hydrolyzed. It is desirable to control the water content of the ester oil to 300 ppm or less. This is because ester oil has hydrolyzability. In addition, acids such as hydrogen chloride produced by decomposition of a refrigerant containing at least one of chlorine, bromine, and iodine combine with moisture to corrode metal parts such as the magnet 44.

Refrigerating machine oil may contain radical polymerization inhibitors, antioxidants, acid scavengers, extreme pressure agents (antiwear agents), oxygen scavengers, and the like as additives. Details of the additive will be explained in Embodiment 3 below.

When the compressor includes a rotor with neodymium magnets or when the refrigeration cycle equipment includes parts made of brass, halogenated hydrocarbons bonded with halogens other than fluorine are likely to come into contact with the neodymium magnets or brass and be decomposed. . Even when the refrigeration cycle circuit of this embodiment includes parts made of neodymium magnets and brass, by using the above-mentioned refrigeration oil, polymerization of the HFO-based refrigerant can be suppressed, and the refrigeration cycle circuit has high reliability. and compressor can be realized.

Embodiment 2.
The refrigeration cycle device of Embodiment 2 can have the same configuration as the refrigeration cycle device of Embodiment 1, except that the second compound is included as the refrigeration oil. In Embodiment 2, a case where the refrigerating machine oil contains the second compound will be described.

The second compound will be explained. The second compound includes an oxygen atom and a second alkyl group having a primary carbon or a secondary carbon adjacent to the oxygen atom. The second compound is polyvinyl ether, and the second alkyl group that binds to oxygen is preferably a methylene group or a methine group, and other parts can be adjusted depending on the solubility and lubricity with the refrigerant. can.

The refrigerating machine oil used in this embodiment can include a second compound. In this case, the content of the second compound in the refrigerating machine oil can be appropriately set in consideration of compatibility with the refrigerant.

Regarding the mechanism by which radical polymerization can be suppressed when a second compound containing an oxygen atom and a secondary alkyl group having a primary carbon or secondary carbon adjacent to the oxygen atom is used as a refrigerating machine oil. This will be explained below. When an ether oil containing an oxygen atom and a secondary alkyl group having a primary carbon adjacent to the oxygen atom is used as the second compound, as shown in the following reaction formula (4), CF ₃ - The radical extracts a hydrogen atom from the carbon atom (primary carbon) adjacent to the oxygen atom in the second compound. In the reaction formula below, R4, R5 and R6 are each an alkyl group or hydrogen.

As shown in the above reaction formula (4), hydrogen bonded to the carbon bonded to the oxygen atom easily stabilizes the CF ₃ radical by donating hydrogen to the CF ₃ radical. As in the second compound shown in reaction formula (4) above, when two hydrogen atoms are bonded to a carbon atom that is bonded to an oxygen atom, the carbon atom is a primary carbon, but it appears to be a secondary carbon atom. class carbon. The reaction enthalpy change when hydrogen bonded to the carbon atom is abstracted is -52 KJ/mol. The value of this reaction enthalpy change is smaller than the reaction enthalpy change (-32 KJ/mol) when hydrogen abstraction occurs at the γ-position of the first compound shown in the above formula (3). Therefore, even if two hydrogen atoms are bonded to a carbon atom that is bonded to an oxygen atom, these hydrogen atoms are likely to bond to CF ₃ · in the same way as hydrogen atoms bonded to tertiary carbons.

In the second compound, when one hydrogen atom is bonded to a carbon atom that is bonded to an oxygen atom, the carbon atom is a secondary carbon, but it appears to be a tertiary carbon. The reaction enthalpy change when the hydrogen atom bonded to the carbon atom is extracted is approximately -60 KJ/mol. Therefore, even if one hydrogen atom is bonded to a carbon atom that is bonded to an oxygen atom, this hydrogen atom is likely to bond to CF ₃ · in the same way as a hydrogen atom that is bonded to a tertiary carbon.

The hydrogen atom bonded to the carbon atom bonded to the oxygen atom of the second compound is donated to the CF ₃ radical to become CF ₃ H, the function of the CF ₃ radical as a radical polymerization initiator disappears, and the double bond It is presumed that the polymerization of HFO-based refrigerants containing .

Embodiment 3.
In the refrigeration cycle devices of Embodiments 1 and 2, the refrigeration oil may contain an additive. Examples of additives include radical polymerization inhibitors, antiwear agents, acid scavengers, antioxidants, oxygen scavengers, and the like.

By using a radical polymerization inhibitor, it is possible to prevent the refrigerating machine oil from polymerizing with each other following radicalization of the refrigerating machine oil. Thereby, changes in the properties of the refrigeration oil can be suppressed, and the stability of the refrigeration cycle device is improved compared to the case where no radical polymerization inhibitor is added.

As the radical polymerization inhibitor, phenols, hydroquinones, and amines can be used. Among these, phenols are preferred, and 2,6-di-tert-butyl-4-methylphenol and 2,6-di-tert-butyl-4-ethylphenol are most preferred.

The content of the radical polymerization inhibitor in the refrigerating machine oil is preferably 0.1% by mass or more and 3% by mass or less, more preferably 0.5% by mass or more and 2% by mass or less. If the content of the radical polymerization inhibitor in the refrigerating machine oil is less than 0.1% by mass, sufficient effects may not be obtained. If the content of the radical polymerization inhibitor in the refrigerating machine oil exceeds 3% by mass, there is a possibility that performance such as sufficient lubricity may not be obtained.

Using an anti-wear agent can improve the sliding condition. Sliding parts tend to reach high temperatures due to frictional heat, and for this reason, decomposition of refrigerants containing iodine and the like and polymerization of HFO-based refrigerants caused by radicals generated by the decomposition are also likely to occur. Therefore, using an appropriate anti-wear agent together with the base oil according to the present invention prevents the sliding parts from generating heat, leading to further stabilization of the refrigeration cycle device.

Anti-wear agents include phosphate esters, phosphite esters, thiophosphates, and the like. Phosphate esters are most suitable as they do not have a negative effect on the refrigeration cycle.

Examples of the phosphoric acid ester anti-wear agent include triphenyl phosphate, tricresyl phosphate, tricylenyl phosphate, cresyl diphenyl phosphate, xylenyl diphenyl phosphate, and the like.

The content of the phosphate ester anti-wear agent in the refrigerating machine oil is preferably 0.1% by mass or more and 10% by mass or less. According to this, the anti-wear agent is efficiently adsorbed on the surface of the sliding part, and a film with a small shear force is formed on the sliding surface, so that the effect of preventing wear and suppressing the heat generation of the sliding part can be obtained. If the content of the phosphate ester anti-wear agent in the refrigerating machine oil is less than 0.1% by mass, sufficient effects may not be obtained. If the content of the phosphate ester anti-wear agent in the refrigerating machine oil exceeds 10% by mass, corrosive wear may occur.

When an acid scavenger is used, the acid scavenger captures acids generated by the decomposition of various refrigerants, and can prevent corrosion of metals in the refrigeration cycle device and prevent deterioration of organic materials. The acids produced are mainly hydrogen halides.

An epoxy compound can be used as the acid scavenger. The epoxy compound is preferably at least one of glycidyl ether type epoxy and glycidyl ester type epoxy.

Since epoxy also captures moisture, when the refrigerating machine oil contains an epoxy compound, it is desirable that the saturated moisture content of the refrigerating machine oil is higher than the saturated moisture content of the refrigerant. Moisture in the refrigerant is absorbed into the refrigerating machine oil, and the epoxy present in the refrigerating machine oil can efficiently remove the water.

The content of the acid scavenger in the refrigerating machine oil is preferably 0.1% by mass or more and 5% by mass or less. According to this, the acid scavenger captures acids generated by decomposition of various refrigerants, and it is possible to prevent corrosion of metals in the refrigeration cycle device and prevent deterioration of organic materials. If the content of the acid scavenger in the refrigerating machine oil is less than 0.1% by mass, sufficient effects may not be obtained. If the content of the acid scavenger in the refrigerating machine oil exceeds 5% by mass, there is a possibility that the epoxy will polymerize and produce sludge.

Examples of antioxidants include 2,6-di-tert-butyl-4-methylphenol, 2,6-di-tert-butyl-4-ethylphenol, and 2,2'-methylenebis(4-methyl-6-tert). -butylphenol), phenyl-α-naphthylamine, and N. Examples include amines such as N'-di-phenyl-p-phenylenediamine.

Examples of the oxygen scavenger include sulfur-containing aromatic compounds, various olefins, aliphatic unsaturated compounds (dienes, trienes, etc.), cyclic terpenes having unsaturated bonds, and the like.

Examples of sulfur-containing aromatic compounds include 4,4'-thiobis(3-methyl-6-tert-butylphenol), diphenyl sulfide, dioctyl diphenyl sulfide, dialkyldiphenylene sulfide, benzothiophene, dibenzothiophene, phenothiazine, benzothiapyran, thiapyran, Examples include thianthrene, dibenzothiapyran, diphenylene disulfide, and the like.

Examples of the cyclic terpenes having an unsaturated bond include α-pinene, β-pinene, limonene, and phellandrene. Particularly preferred are aliphatic unsaturated compounds, cyclic terpenes having an unsaturated bond, and the like.

The refrigeration oil may be free of quinone additives. Quinone additives include 1,4-benzoquinone, 1,2-benzoquinone, 2-methyl-1,4-benzoquinone, 2-phenyl-1,4-benzoquinone, 2-tert-butyl-1,4-benzoquinone, 1 , 4-naphthoquinone, 1,2-naphthoquinone, 2,6-naphthoquinone, 2-hydroxy-1,4-naphthoquinone, and 1,4-anthraquinone. Since quinone additives can capture and inactivate radicals generated by the decomposition of R-13I1, their addition to refrigerating machine oil is being considered. On the other hand, in the refrigeration cycle apparatuses of Embodiments 1 to 3, by using the refrigeration oil containing one or both of the first compound and the second compound, radicals generated by decomposition of R-13I1 etc. are removed from the first compound and the second compound. Reacts with a second compound. As a result, the function of the radical as a polymerization initiator is suppressed, and the polymerization of the HFO-based refrigerant is suppressed. Therefore, the refrigerating machine oil used in this embodiment can be made free of quinone additives.

Embodiment 4.
A refrigeration cycle device according to a fourth embodiment includes a refrigerant, a compressor 1 that compresses the refrigerant, refrigeration oil that lubricates the sliding parts of the compressor 1, and a refrigerant pipe 5 through which the refrigerant passes. It is. The refrigerant includes a first refrigerant and a third refrigerant. The first refrigerant is a hydrofluoroolefin refrigerant, and the third refrigerant is a refrigerant containing at least one element selected from the group consisting of chlorine, bromine, and iodine. The third refrigerant is not limited to the case where it is used intentionally, but also includes the case where it remains in the existing compressor or piping and is reused and mixed into a newly introduced refrigeration cycle device. Refrigerating machine oil contains one or both of the first compound and the second compound. The first compound includes a first alkyl group having at least one tertiary carbon, and the second compound includes a second alkyl group having an oxygen atom and a primary carbon or a secondary carbon adjacent to the oxygen atom. and, including. One or both of the compressor 1 and the refrigerant piping 5 is one that reuses one or both of the existing compressor and the existing refrigerant piping in a refrigeration cycle device that has a history of using the third refrigerant. In the refrigeration cycle device of Embodiment 4, the polymerization reaction of the HFO-based refrigerant is suppressed and sludge does not occur, so the reliability of the refrigeration cycle device can be ensured. The reason for this will be explained below.

In Embodiments 1 to 3, a halogenated hydrocarbon containing at least one element selected from the group consisting of chlorine, bromine, and iodine is used in combination with an HFO-based refrigerant (first refrigerant). It has been assumed that the HFO refrigerant is polymerized by CF ₃ radicals, which are decomposition products of the second refrigerant. However, in the demand for replacement of air conditioners, etc., the newly used refrigerant contains a halogenated hydrocarbon (secondary refrigerant) containing at least one element selected from the group consisting of chlorine, bromine, and iodine. Even if the halogenated hydrocarbon is not present, the same problems may occur as when the halogenated hydrocarbon is included. For example, when replacing an air conditioner, the existing compressor and refrigerant piping may be reused. In this case, a conventionally used refrigerant such as a chlorine-based refrigerant may be mixed into an air conditioner or the like that uses a newly introduced HFO-based refrigerant. Among conventionally used refrigerants, refrigerants that can cause the above problem are chlorine-based refrigerants regulated by the Montreal Protocol on Substances that Deplete the Ozone Layer, such as HCFC22, HCFC123, and CFC12.

In HCFC22, HCFC123, and CFC12, chlorine is easily eliminated to generate radicals. Therefore, when HCFC22, HCFC123, CFC12, etc. are mixed into the HFO-based refrigerant, the radicals generated from HCFC22, HCFC123, CFC12, etc. proceed to polymerize the HFO-based refrigerant. In order to suppress this polymerization reaction, it is necessary to use the refrigerating machine oil described in Embodiments 1 to 3. By using the refrigerating machine oils described in Embodiments 1 to 3, it is possible to prevent the reliability of the refrigeration cycle device from decreasing due to polymerization products of HFO-based refrigerants. Embodiments 1 to 3 describe when replacing a refrigeration cycle device that has a history of using a refrigerant containing a halogen other than fluorine (such as chlorine) with a refrigeration cycle device that uses a refrigerant that includes an HFO-based refrigerant. By using this refrigerating machine oil, radical polymerization of HFO refrigerant due to decomposition of refrigerant remaining in existing piping, etc. to be reused at the time of replacement can be suppressed, and a highly reliable refrigeration cycle device and compressor can be realized.

The reason why a conventional chlorine-based refrigerant such as HCFC22 is mixed with a newly introduced refrigerant containing an HFO-based refrigerant will be explained using a building air conditioner as an example. When replacing a building air conditioner, etc., the existing refrigerant piping buried in the wall is often used as is. When refrigeration oil remains in the refrigerant piping, the refrigerant often remains dissolved in the refrigeration oil.

When changing from an old refrigerant to a new refrigerant in a building air conditioner, it is common to change to a new refrigerating machine oil that is compatible with the new refrigerant. In this case, the refrigerant and refrigeration oil that have been used up to now are recovered into the outdoor unit through pump-down operation, and the outdoor and indoor units are replaced with the new refrigerant by replacing the refrigerant with one that is compatible with the new refrigerant. As an example of pump-down operation, the method described in JP-A-62-280548 can be used. After collecting the old refrigerant and old refrigeration oil into the outdoor unit through pump-down operation, remove the outdoor unit and replace it with an outdoor unit filled with new refrigeration oil. After that, it is common to evacuate and seal new refrigerant into the refrigerant pipes.

Refrigerant pipes buried in walls often have complicated flow paths because they branch to multiple indoor units. In addition, the flow path changes as the number of indoor units increases or decreases, and there are many refrigerant pipes, so-called caecal pipes, etc. that are not used midway. In such a refrigerant pipe with one end blocked, there is no flow of refrigerant, so even if the pipe is pumped down, refrigerating machine oil tends to remain with the refrigerant dissolved therein.

Refrigerant oil that was previously used remains in the existing refrigerant piping, and the refrigerant dissolved in the residual refrigerant oil is difficult to remove by vacuuming, and there is a very high possibility that it will mix with the new refrigerant. Even though the new refrigerant does not contain conventional chlorine-based refrigerants, which can cause problems, the result is a mixed refrigerant of conventional chlorine-based refrigerants and HFO-based refrigerants.

The above explanation was based on the case where pump-down operation is possible, but if the compressor is out of order, pump-down operation cannot be performed. In such a situation, the amount of residual refrigerating machine oil further increases, and the amount of conventional chlorine-based refrigerant that remains dissolved in the refrigerating machine oil also increases. Conventional chlorine-based refrigerants only need to contain chlorine and are not subject to GWP or ODP restrictions. This is because when such refrigerants were used, they were not regulated by GWP or ODP, or the regulations were more relaxed than they are now.

If the refrigerant used after replacement contains an HFO refrigerant, even if the refrigerant does not contain chlorine, bromine, or iodine, there is a risk that polymerization of the HFO refrigerant will occur as in the case described above. There is. For this reason, if a building air conditioner or the like has a history of using a chlorine-based refrigerant such as HCFC22, and if a refrigerant containing an HFO-based refrigerant is used after replacement, please refer to Embodiments 1 to 3. By using the refrigerating machine oil, polymerization of the HFO refrigerant can be suppressed, and the refrigeration cycle can be stabilized. Therefore, the refrigeration cycle apparatuses of Embodiments 1 to 3 are equipped with refrigerant piping through which the refrigerant passes, and one or both of the compressor and refrigerant piping is the same as the compressor and refrigerant piping in the refrigeration cycle apparatus using the third refrigerant. The third refrigerant may be a refrigerant containing at least one element selected from the group consisting of chlorine, bromine, and iodine. Here, the third refrigerant corresponds to an existing refrigerant.

The amount of existing refrigeration oil mixed into new refrigeration oil cannot be determined with certainty, as it depends on the complexity of the piping, the method of replacement work, and the skill of the replacement worker. Generally, the ratio of the amount M2 of existing refrigerating machine oil to the amount M1 of new refrigerating machine oil on a mass basis is often about 10 to 50%. Refrigerant dissolved in refrigerating machine oil is difficult to remove simply by vacuuming and is likely to remain in the refrigerant circuit. When changing from HCFC22 to HFC-based refrigerant and then to HFO-based refrigerant, the ratio of the amount of existing refrigeration oil M2 to the amount of new refrigeration oil M1 on a mass basis may be about 1 to 25%. It is said that there are many. For this reason, when changing to an HFO-based refrigerant in a model of a refrigeration cycle device that used HCFC22, there is a possibility that the HCFC22 dissolved in the existing refrigerating machine oil may mix into the HFO-based refrigerant.

The amount M2 of the existing refrigeration oil corresponds to the difference between the amount of the existing refrigeration oil sealed and the amount of the existing refrigeration oil recovered. Therefore, by dividing the amount M1 of newly filled refrigeration oil by the difference M2 between the amount of existing refrigeration oil filled in and the amount of recovered refrigeration oil, the amount of new refrigeration oil The mass-based ratio M1/M2 of the amount M2 of machine oil can be determined.

If the amount of existing refrigerating machine oil is unknown, after filling in new refrigerating machine oil and refrigerant, operate the machine for a sufficient period of time, and calculate the amount of existing refrigerating machine oil contained in the refrigerating machine oil extracted after operation. It can be determined using an analytical device. A liquid chromatograph or a gas chromatograph is preferably used as the analysis device. Based on the specific gravity of the refrigerating machine oil extracted after operation, the amount of existing refrigerating machine oil in the refrigerating machine oil can be determined.

It is difficult to predict how much residual HFO-based refrigerant will promote polymerization. This is because it depends not only on the type of residual refrigerant and the reactivity of the newly used HFO refrigerant, but also on the temperature of the newly introduced compressor. Therefore, testing to determine whether there is a problem is complicated and impractical. If there is a history of using refrigerants that cause problems, the refrigerating machine oils described in Embodiments 1 to 3 should be used. If a standard were to be set for the amount of existing refrigerating machine oil mixed in, the concentration in new refrigerating machine oil would be 1% by mass or less. If the amount of existing refrigeration oil in the new refrigeration oil exceeds 1% by mass, the compatibility between the newly introduced HFO refrigerant and the new refrigeration oil will deteriorate, and a large amount of the existing refrigeration oil will remain. This is because polymerization of the HFO-based refrigerant is promoted.

Conventionally used refrigerating machine oil containing refrigerant cannot be removed by just pumping it down, and if the compressor has failed, pumping it down cannot be done either. For this reason, techniques are also being considered for cleaning the refrigerant pipes to reduce the amount of refrigerating machine oil remaining in the refrigerant pipes. A method of reducing the amount of refrigeration oil remaining in refrigerant piping by repeating the exchange of refrigerant and refrigeration oil multiple times has been studied (Japanese Patent Laid-Open No. 7-83545). Generally, the refrigerating machine oil remaining in the refrigerant piping is the mineral oil that was used with the HCFC22. The refrigerant used for repeated cleaning is an HFC refrigerant, and the refrigerating machine oil used at this time is an ester oil or ether oil that is compatible with the HFC refrigerant. Mineral oil is insoluble in HFC-based refrigerants, so even if cleaning is repeated with HFC-based refrigerants, mineral oil remains inside the pipes. It is also known that ester oil mixed with mineral oil is also insoluble in HFC refrigerants.

Assuming that mineral oil can be cleaned with HFC-based refrigerant, there should be less refrigeration oil remaining in the refrigerant piping, and less chlorine-based refrigerant should be mixed in. However, the halogen-containing refrigerant merely functions as a radical reaction initiator and is sufficient if it becomes a starting point for the polymerization of the HFO-based refrigerant, so problems may occur if a trace amount remains. Therefore, even if the refrigerant pipes are cleaned, the effect of suppressing the polymerization of the HFO-based refrigerant cannot be sufficiently obtained.

When cleaning refrigerant piping with a cleaning liquid, if a halogen compound other than fluorine is used in the cleaning liquid, the cleaning liquid remains in the refrigerant piping, and this serves as a starting point for polymerization of the HFO-based refrigerant. Examples of compounds containing halogens other than fluorine include methylene chloride, 1-bromopropane, HCFC141b and HCFC225. If there is a history of cleaning the inside of the refrigerant piping with these cleaning liquids, there is a high possibility that the cleaning liquid remains in the refrigerant piping even if a chlorine-free refrigerant is used after cleaning.

An example will be described where a chlorine-based refrigerant has been used in the compressor to be replaced, and the refrigerant to be newly filled is an HFO-based refrigerant. First, the refrigerant is recovered into the outdoor unit by pump-down operation. The recovered refrigerant is a single chlorine-based refrigerant or a refrigerant mixed with a chlorine-based refrigerant. Next, the outdoor unit is removed, and an outdoor unit filled with refrigerating machine oil used together with HFO-based refrigerant is connected. In this case, replace the indoor unit, etc. as necessary. The refrigerating machine oil used at this time is a refrigerating machine oil containing one or both of the first compound and the second compound described in Embodiments 1 to 3. Thereafter, the chamber is evacuated and filled with a refrigerant containing at least an HFO refrigerant. When other refrigerants are included in addition to the HFO refrigerant, the other refrigerants are preferably HFC refrigerants. Furthermore, after a short period of operation, the refrigerant and refrigerating machine oil may be replaced in an attempt to reduce the residual amount of the conventionally used chlorine-based refrigerant. By using the refrigeration oil described in Embodiments 1 to 3, even if chlorine-based refrigerant remains, the polymerization reaction of the HFO-based refrigerant is suppressed and sludge does not occur, thereby improving the reliability of the refrigeration cycle device. Can be secured.

Embodiment 5.
<Compressor>
The compressor according to Embodiment 5 is a compressor used in a refrigeration cycle device, and the refrigeration cycle device includes a refrigerant, a compressor that compresses the refrigerant, and refrigeration oil that lubricates sliding parts of the compressor. and, the refrigerant includes a first refrigerant and a second refrigerant, the first refrigerant is a hydrofluoroolefin refrigerant, and the second refrigerant is selected from the group consisting of chlorine, bromine, and iodine. The refrigerating machine oil is a halogenated hydrocarbon containing at least one element, and the refrigerating machine oil contains one or both of a first compound and a second compound, and the first compound is a first alkyl group having at least one tertiary carbon. , the second compound is a compressor, comprising an oxygen atom and a second alkyl group having a primary or secondary carbon adjacent to the oxygen atom.

The refrigerating machine oil used in the compressor of the fifth embodiment has the same structure as the refrigerating machine oil described in the first to third embodiments. Therefore, in the refrigeration cycle apparatus using the compressor of Embodiment 5, the polymerization reaction of the HFO-based refrigerant is suppressed and sludge does not occur, so that the reliability of the refrigeration cycle apparatus can be ensured.

Embodiment 6.
<Compressor>
The compressor according to Embodiment 6 is a compressor used in a refrigeration cycle device, and the refrigeration cycle device includes a refrigerant, a compressor that compresses the refrigerant, and refrigeration oil that lubricates sliding parts of the compressor. and a refrigerant pipe through which the refrigerant passes, the refrigerant includes a first refrigerant and a third refrigerant, the first refrigerant is a hydrofluoroolefin refrigerant, and the third refrigerant is a refrigerant containing chlorine, bromine, etc. and iodine, the refrigerating machine oil contains one or both of a first compound and a second compound, and the first compound contains at least one tertiary carbon. The second compound includes a first alkyl group having an oxygen atom and a second alkyl group having a primary carbon or a secondary carbon adjacent to the oxygen atom, and the second compound includes a first alkyl group having a primary carbon or a secondary carbon adjacent to the oxygen atom, Both are compressors that reuse an existing compressor and existing refrigerant piping in a refrigeration cycle device that has a history of using the third refrigerant.

The refrigerating machine oil used in the compressor of the sixth embodiment has the same structure as the refrigerating machine oil described in the first to third embodiments. Therefore, in the refrigeration cycle apparatus using the compressor of Embodiment 6, the polymerization reaction of the HFO-based refrigerant is suppressed and sludge does not occur, so the reliability of the refrigeration cycle apparatus can be ensured.

The embodiments and examples disclosed this time should be considered to be illustrative in all respects and not restrictive. The scope of the present disclosure is indicated by the claims rather than the above description, and it is intended that equivalent meanings and all changes within the scope of the claims are included.

1 Compressor, 2 Condenser, 3 Expansion valve, 4 Evaporator, 5 Refrigerant piping, 5a to 5d Refrigerant piping, 6 Condenser blower, 7 Evaporator blower, 8 Shell, 9 Compression mechanism, 10 Suction pipe, 11 Discharge pipe , 12 shaft, 13 oil reservoir, 14 oil supply hole, 15 short bearing, 16 long bearing, 17 rotor, 18 stator, 100 refrigeration cycle device, 200 electric refrigerant compressor, 41 stator, 42 rotor, 43 rotation Child core, 43a magnet insertion hole, 43b refrigerant passage hole, 43c shaft hole, 44 magnet, 45 film.

Claims (8)

refrigerant and
a compressor that compresses the refrigerant;
Refrigerating machine oil that lubricates the sliding parts of the compressor;
A refrigeration cycle device comprising: a refrigerant pipe through which the refrigerant passes;
The refrigerant includes a first refrigerant,
The first refrigerant is a hydrofluoroolefin refrigerant,
The refrigeration oil contains one or both of a first compound and a second compound,
The first compound is a compound selected from the group consisting of polyol esters, polyvinyl ethers, and polyalkylene glycols containing a first alkyl group having at least one tertiary carbon,
The polyol ester is an ester of a diol or polyol and a fatty acid,
The fatty acid is isobutyric acid, 2-methylhexanoic acid, 2-ethylpentanoic acid, 2-ethylhexanoic acid, or 3,5,5-trimethylhexanoic acid,
The diol or polyol is neopentyl glycol, trimethylolethane, trimethylolpropane, trimethylolbutane, di-(trimethylolpropane), tri-(trimethylolpropane), pentaerythritol, di-(pentaerythritol), or Tory (pentaerythritol),
The first alkyl group contained in the polyvinyl ether is an isobutyl group, a sec-butyl group, a cyclobutyl group, or an isopropyl group,
The polyalkylene glycol is a compound in which at least one of both ends is capped with an ether bond, and the tertiary carbon is contained in the first alkyl group bonded to the capped ether bond,
The first alkyl group contained in the polyalkylene glycol is an isopropyl group, an isobutyl group, a sec-butyl group, or a cyclobutyl group,
The second compound is a polyvinyl ether containing an oxygen atom and a second alkyl group having a primary carbon or a secondary carbon adjacent to the oxygen atom,
The part of the second alkyl group that binds to oxygen is a methylene group or a methine group,
One or both of the compressor and the refrigerant piping is an existing compressor and one of the existing refrigerant piping in a refrigeration cycle device that has a history of using a third refrigerant consisting of one or both of an HCFC refrigerant and a CFC refrigerant. Or refrigeration cycle equipment that reuses both. The refrigeration cycle device according to claim 1, wherein the third refrigerant includes at least one selected from the group consisting of HCFC22, HCFC123, and CFC12. The first refrigerant is R-1132a, HFO-1132 (E), HFO-1132 (Z), HFO-1123, HFO-1225ye (Z), HFO-1225ye (E), HFO-1225zc, R-1234yf, Claim 1 or 2 consisting of at least one selected from the group consisting of R-1234ze (E), HFO-1234ze (Z), HFO-1234ye (Z), HFO-1234ye (E), and HFO-1243zf. The refrigeration cycle device described in . The refrigeration cycle device according to claim 1 or 2, wherein the refrigeration oil contains a radical polymerization inhibitor. The refrigeration cycle device according to claim 4, wherein the radical polymerization inhibitor is a phenol. The refrigeration cycle device according to claim 1 or 2, wherein the compressor includes a rotor having a neodymium magnet. The refrigeration cycle device according to claim 1 or 2, wherein the refrigeration cycle device includes parts made of brass. A compressor used in a refrigeration cycle device,
The refrigeration cycle device includes:
refrigerant and
a compressor that compresses the refrigerant;
Refrigerating machine oil that lubricates the sliding parts of the compressor;
A refrigerant pipe through which the refrigerant passes,
The refrigerant includes a first refrigerant,
The first refrigerant is a hydrofluoroolefin refrigerant,
The refrigeration oil contains one or both of a first compound and a second compound,
The first compound is a compound selected from the group consisting of polyol esters, polyvinyl ethers, and polyalkylene glycols containing a first alkyl group having at least one tertiary carbon,
The polyol ester is an ester of a diol or polyol and a fatty acid,
The fatty acid is isobutyric acid, 2-methylhexanoic acid, 2-ethylpentanoic acid, 2-ethylhexanoic acid, or 3,5,5-trimethylhexanoic acid,
The diol or polyol is neopentyl glycol, trimethylolethane, trimethylolpropane, trimethylolbutane, di-(trimethylolpropane), tri-(trimethylolpropane), pentaerythritol, di-(pentaerythritol), or Tory (pentaerythritol),
The first alkyl group contained in the polyvinyl ether is an isobutyl group, a sec-butyl group, a cyclobutyl group, or an isopropyl group,
The polyalkylene glycol is a compound in which at least one of both ends is capped with an ether bond, and the tertiary carbon is contained in the first alkyl group bonded to the capped ether bond,
The first alkyl group contained in the polyalkylene glycol is an isopropyl group, an isobutyl group, a sec-butyl group, or a cyclobutyl group,
The second compound is a polyvinyl ether containing an oxygen atom and a second alkyl group having a primary carbon or a secondary carbon adjacent to the oxygen atom,
The part of the second alkyl group that binds to oxygen is a methylene group or a methine group,
One or both of the compressor and the refrigerant piping is an existing compressor and an existing refrigerant piping in a refrigeration cycle device that has a history of using a third refrigerant consisting of one or both of an HCFC refrigerant and a CFC refrigerant. A compressor was used.

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