JP2012031239A - Compressor for refrigeration and air-conditioning, and refrigeration and air-conditioning apparatus - Google Patents

Abstract

An object of the present invention is to improve the wear resistance of a compressor for refrigeration and air conditioning, and to realize high efficiency of a refrigeration air conditioner using the compressor.
A refrigerant containing 2,3,3,3-tetrafluoropropene, 1,3,3,3-tetrafluoropropene, and the like includes a refrigerating machine main agent such as polyol ester oil and an added polyol ester oil. A compressor for refrigerating and air conditioning in which refrigeration oil is mixed and sealed is used. The composition of the added polyol ester oil is 1 to 30% by weight.
[Selection] Figure 1

Description

  The present invention relates to a refrigeration and air conditioning compressor and a refrigeration air conditioning apparatus using a heat pump cycle.

  Global environmental measures in the field of refrigerating and air-conditioning equipment include substitution of CFC (Chlorofluorocarbons) and HCFC (Hydrochlorofluorocarbons), which have been used as refrigerants and heat insulating materials as ozone depleting substances, as well as higher efficiency and refrigerants as a countermeasure against global warming Substitutes for HFC (Hydrofluorocarbons) used in Japan, and these have been actively promoted.

  As alternatives to CFCs and HCFCs, which are ozone-depleting substances, the selection of refrigerants and heat insulating materials and equipment development were promoted with the main objective of not destroying the ozone layer, low toxicity and low flammability, and ensuring efficiency. . As a result, in the heat insulating material of the refrigerator, the foaming agent is replaced in the order of HCFC141b and cyclopentane in CFC11, and now it is shifted to the combined use with the vacuum heat insulating material.

  As a refrigerant, CFC12C is replaced with HFC134a (Global Warming Potential GWP = 1430) in the order of refrigerators and car air conditioners, and HCFC22 is replaced with R410A (HFC32 / HFC125 (50/50% by weight) in room air conditioners and packaged air conditioners. ) Mixture: replaced with GWP = 2088).

However, at the Conference of the Parties to the 3rd Framework Convention on Climate Change, which was held in Kyoto in 1997 (COP3), for HFC emissions has become subject to regulation are terms of CO ₂ as a greenhouse gas, reduction of HFC is advanced It became a thing.

  In view of this, in the refrigerator for home use, it was judged that the amount of refrigerant enclosed was small and a flammable refrigerant could be used for manufacturing, and HFC134a was replaced with flammable R600a (isobutane: GWP = 3). Furthermore, due to the growing public opinion, attention is now focused on the HFC134a for car air conditioners, the room air conditioner and the R410A for packaged air conditioners. Moreover, in commercial refrigerators, the amount of R600a enclosed is large, and HFC134a is still used because of the fear of flammability.

  In reality, recycling of equipment is obligated by the Home Appliance Recycling Law (Specific Home Appliance Recycling Law) enacted in 2001 and the Automobile Recycling Law (Law Concerning Recycling of Used Cars) Enforced in 2003 HFC and the like used as a refrigerant are collected and processed. However, in the EU (European Union), in the 2006 Directive (Directive 2006/40 / EC), the use of a refrigerant with GWP> 150 as a refrigerant used in a car air conditioner was prohibited from the shipment in January 2011. In response, the car air conditioner industry has made various moves, and there is a concern that room air conditioners will eventually be restricted by R410A. Based on the EU directive, there is a possibility of reviewing regulations including stationary air conditioners in 2011, and studies on alternative refrigerants are accelerating.

  These alternative refrigerants have the same thermophysical properties as HFC134a, and because of low GWP, low toxicity, low flammability, etc., 2, 3, 3, 3-tetrafluoropropene (HFO1234yf (Hydrofluorinefine) (GWP = 4) or 1,3,3,3-tetrafluoropropene (HFO1234ze) (GWP = 10) alone or a mixed refrigerant thereof is a candidate, and is mixed with 2,3,3,3-tetrafluoropropene. As the refrigerant, difluoromethane (HFC32) is mainly used.

  Furthermore, HFC134a and HFC125 may be mixed depending on the GWP allowed for low combustibility. Other refrigerants include hydrocarbons such as propane and propylene, and low GWP hydrofluorocarbons such as fluoroethane (HFC161), difluoroethane (HFC152a), and difluoromethane (HFC32).

  On the other hand, refrigeration oil is used in a hermetic electric compressor and plays a role of lubrication, sealing, cooling and the like of a sliding portion thereof.

  In the air conditioner, APF (Annual Performance Factor) is adopted as an index indicating energy saving performance in accordance with the actual use state according to the Energy Saving Law (Act on the Rational Use of Energy) revised from 2006. There is a need for energy saving and high efficiency. Since use conditions become severe in this way, refrigerating machine oil with good lubricity is required in terms of ensuring reliability.

  As refrigerating machine oil used in a compressor using a single refrigerant of 2,3,3,3-tetrafluoropropene (HFO1234yf) and 1,3,3,3-tetrafluoropropene (HFO1234ze) or a mixed refrigerant containing these refrigerants From the above situation, polyalkylene glycol oil, mineral oil, poly α-olefin oil and alkylbenzene oil are disclosed (for example, Patent Document 1).

  Patent Document 2 discloses that a refrigerating machine oil composed of at least one of paraffinic refrigerating machine oil, naphthenic refrigerating machine oil, and synthetic refrigerating machine oil has a boiling point of 50 to 250 ° C. at normal pressure and a viscosity of 5 centistokes / A refrigerating machine oil composition comprising a fraction that is 40 ° C. or lower is disclosed.

  In addition, Patent Documents 3 and 4-9 include HFO-1234yf, HFO-1225yeZ, trans-1,3,3,3-pentafluoropropane (transHFO-1234ze), 1,1-difluoroethane (HFC-152a). 1, 1, 1, 2, 3, 3, 3-heptafluoropropane (HFC-227ea), 1, 1, 1, 2-tetrafluoroethane (HFC-134a), 1, 1, 1, 2, 2 -An azeotrope-like composition containing pentafluoroethane (HFC-125), etc., and mineral oil (including paraffin oil or naphthenic oil), silicone oil, polyalkylbenzene, polyol ester, polyalkylene glycol, polyalkylene glycol ester , Polyvinyl ether, poly (α-olefin), halocarbon oil, etc. There has been disclosed.

Special table 2009-540170 gazette JP 58-93796 A Special table 2007-532767 Special table 2007-538115 gazette Special table 2008-504374 Special table 2008-505989 JP 2008-506793 A Special table 2008-524433 Special table 2008-239814

  2,3,3,3-tetrafluoropropene (HFO1234yf) and 1,3,3,3-tetrafluoropropene (HFO1234ze) are low-pressure refrigerants compared to R410A, so they are compressed to obtain a refrigerant circulation rate. It is essential to increase the capacity and speed of the machine. For this reason, in the case of the above-described refrigerating machine oil, a problem relating to wear resistance remains in a sliding portion such as a compressor bearing.

  In addition, refrigerants such as HFO1234yf, HFO1234ze, propane, propylene, and fluoroethane have a very high solubility in the above-described refrigerating machine oil, and the refrigerant has a high solubility in the compressor, so that the refrigerant melt viscosity in the refrigerating machine oil decreases. . For this reason, the problem of the fall of the sealing performance of a compression part and the increase in the amount of wear of a sliding part arises.

  For the reasons described above, it is preferable to use a refrigerating machine oil that can achieve both improvement in equipment efficiency and wear resistance for the refrigerating and air-conditioning apparatus.

  An object of the present invention is to provide a refrigerant containing 2,3,3,3-tetrafluoropropene, 1,3,3,3-tetrafluoropropene or the like as a refrigerant, or a hydrocarbon such as propane or propylene, or fluoroethane (HFC161). In addition to improving the wear resistance of refrigeration and air conditioning compressors that use refrigerants for refrigeration and air conditioning such as difluoroethane (HFC152a), difluoromethane (HFC32), R410A, etc., and realizing higher efficiency in refrigeration and air conditioning equipment using this compressor There is to do.

  The compressor for refrigerating and air-conditioning of the present invention is added to a refrigerant containing 2, 3, 3, 3-tetrafluoropropene, 1, 3, 3, 3-tetrafluoropropene and the like, and a refrigerating machine oil main component such as polyol ester oil, and the like A refrigerating machine oil containing a polyol ester oil is mixed and sealed, and the composition of the added polyol ester oil is 1 to 30% by weight.

  ADVANTAGE OF THE INVENTION According to this invention, the compressor which was compatible with the performance improvement of a compressor, and abrasion resistance can be obtained, without using the phosphorus extreme pressure agent harmful | toxic to an environment as an additive of refrigerating machine oil.

  In addition, according to the present invention, an environment-friendly refrigeration air conditioner that can achieve both improved performance and long-term reliability of a refrigeration air conditioner without using a phosphorous extreme pressure agent harmful to the environment as an additive for refrigeration oil is obtained. be able to.

It is a schematic block diagram which shows a room air conditioner. It is sectional drawing which shows the scroll-type hermetic compressor for room air conditioners.

  Hereinafter, a refrigerating and air conditioning compressor according to an embodiment of the present invention and a refrigerating and air conditioning apparatus using the same will be described.

The compressor for refrigerating and air-conditioning uses a refrigerant containing 2,3,3,3-tetrafluoropropene, 1,3,3,3-tetrafluoropropene or difluoromethane, or an enclosed refrigerant which is R410A, represented by the following chemical formula (1) And a refrigerating machine main agent containing at least one kind of base oil selected from the group consisting of polyol ester oils represented by (2) (wherein R ₁ represents an alkyl group having 5 to 9 carbon atoms); A refrigerating machine oil containing an additive polyol ester oil represented by the following chemical formula (3) (wherein R ₂ represents an alkyl group having 7 to 9 carbon atoms) is mixed and enclosed.

The compressor for refrigerating and air-conditioning uses mineral oil or polyvinyl as an enclosed refrigerant, which is a refrigerant containing 2, 3, 3, 3-tetrafluoropropene, 1, 3, 3, 3-tetrafluoropropene, propane, propylene, or fluoroethane. At least one group selected from the group consisting of an ether oil or a polyol ester oil represented by the above chemical formulas (1) and (2) (wherein R ₁ represents an alkyl group having 5 to 9 carbon atoms). Refrigerating machine oil main agent containing oil and having a low temperature side critical dissolution temperature of −30 ° C. or less, and an added polyol ester oil represented by the above chemical formula (3) (wherein R ₂ represents an alkyl group having 7 to 9 carbon atoms) )) Is mixed and sealed. The composition of the added polyol ester oil is 1 to 30% by weight.

In the refrigerating and air-conditioning compressor, kinematic viscosity at 40 ° C. of the refrigerating machine oil base resin is in the range of 25~120mm ² / s, that kinematic viscosity at 40 ° C. for the addition polyol ester oil is 180 mm ² / s or more desirable.

  The refrigerating and air-conditioning apparatus depressurizes the refrigerating and air-conditioning compressor, a heat exchanger for dissipating heat of the enclosed refrigerant discharged from the refrigerating and air-conditioning compressor, and the enclosed refrigerant flowing out of the heat exchanger. And a heat exchanger for heating the sealed refrigerant decompressed by the decompression unit.

In the refrigerating and air-conditioning apparatus, the kinematic viscosity at 40 ° C. of the refrigerating machine oil main agent is 25 to 120 mm ² / s, and the adsorption ability of the added polyol ester oil to the iron-based material is twice or more higher than that of the refrigerating machine oil main agent. It is desirable.

The compressor for refrigerating and air-conditioning is obtained by adding a polyol ester oil represented by the above chemical formulas (1) and (2) to a refrigerant having a global warming potential of 1000 or less or a refrigerating and air-conditioning refrigerant having R410A (wherein R ₁ represents an alkyl group having 5 to 9 carbon atoms.) A main component of a refrigerating machine oil containing at least one base oil selected from the group consisting of: a kinematic viscosity at 40 ° C. of 25 to 120 mm ² / s, and the above chemical formula Refrigerating machine oil containing additive polyol ester oil represented by (3) (wherein R ₂ represents an alkyl group having 7 to 9 carbon atoms) is mixed and enclosed.

  The composition of the added polyol ester oil is desirably 1 to 30% by weight.

The compressor for refrigeration and air conditioning includes a scroll type or rotary type hermetic compressor with a built-in motor, a twin rotary type compressor, a two-stage compression rotary type compressor, and a swing in which rollers and vanes are integrated. It is desirable that the kinematic viscosity at 40 ° C. of the refrigerating machine oil main component is 25 mm ² / s to 120 mm ² / s or less, and the kinematic viscosity at 40 ° C. of the added polyol ester oil is preferably 180 mm ² / s or more. .

  The compressor for refrigerating and air-conditioning includes a sliding portion formed of an iron-based material, and a contact surface pressure at the sliding portion is 10 MPa or more.

  In the compressor for refrigerating and air-conditioning, the added polyol ester oil has an adsorption capacity for iron-based materials that is twice or more higher than that of the refrigerating machine oil main agent. Furthermore, the adsorption capacity of the added polyol ester oil to the iron-based material is preferably 2 times or more, and more preferably 4 times or more.

  The refrigeration air conditioner uses the scroll type or rotary type compressor described above.

  Hereinafter, it demonstrates in detail using an Example.

  The examples use 2,3,3,3-tetrafluoropropene or 1,3,3,3-tetrafluoropropene or a mixed refrigerant containing these, or propane, propylene, fluoroethane, difluoromethane or R410A as the refrigerant. A compressor and a refrigerating and air-conditioning apparatus using the compressor are disclosed.

  In this specification, the refrigerant for refrigerating and air-conditioning is 2, 3, 3, 3-tetrafluoropropene, 1, 3, 3, 3-tetrafluoropropene or a mixed refrigerant containing these, propane, propylene, fluoroethane, difluoro. A refrigerant having a GWP of 1000 or less, such as methane, and R410A.

  The refrigerating machine oil of an Example contains the addition polyol ester oil whose adsorption capacity with respect to an iron-type material is very higher than a base oil.

  Examples of the base oil having a low adsorption capacity as compared with the added polyol ester oil include mineral oil, polyvinyl ether oil, and polyol ester oil having an ester group in the molecular structure.

  As mineral oil, naphthenic mineral oil and paraffinic mineral oil can be used. As these mineral oils, for example, a distillate obtained by subjecting paraffin-based crude oil, intermediate-based crude oil, or naphthenic-based crude oil to atmospheric distillation, or distilling the residual oil of atmospheric distillation under reduced pressure is refined according to a conventional method. Refined oil obtained by the above, deep dewaxed oil obtained by further deep dewaxing after purification, hydrotreated oil obtained by hydrotreatment, and the like. There are no particular limitations on the purification method at that time, and various methods can be used.

  The polyol ester oil is obtained by a condensation reaction between a polyhydric alcohol and a monovalent fatty acid.

  As the polyol ester oil, a hindered type having excellent thermal stability is preferable, and as the polyhydric alcohol, neopentyl glycol, trimethylolpropane, pentaerythritol and the like are preferable.

  Monovalent fatty acids include n-pentanoic acid, n-hexanoic acid, n-heptanoic acid, n-octanoic acid, 2-methylbutanoic acid, 2-methylpentanoic acid, 2-methylhexanoic acid, 2-ethylhexanoic acid, There are isooctanoic acid, 3,5,5-trimethylhexanoic acid and the like, which are used alone or in combination of two or more.

  As an added polyol ester oil having a high adsorption capacity for iron-based materials, a polyol ester oil containing a large number of ester groups in its molecular structure is desirable, and dipenta is a hindered type synthesized from a polyhydric alcohol and a monovalent fatty acid. Erythritol is mentioned.

  Monovalent fatty acids include n-pentanoic acid, n-hexanoic acid, n-heptanoic acid, n-octanoic acid, 2-methylbutanoic acid, 2-methylpentanoic acid, 2-methylhexanoic acid, 2-ethylhexanoic acid, There are isooctanoic acid, 3,5,5-trimethylhexanoic acid and the like, which are used alone or in combination of two or more.

Although the viscosity grade of the refrigerating machine oil used for the air conditioner and refrigerator of an Example changes with kinds of compressors, in the scroll type compressor, the range whose kinematic viscosity in 40 degreeC is 46-120 mm < ² > / s is preferable. In the rotary compressor, the kinematic viscosity at 40 ° C. is preferably in the range of 25 to 70 mm ² / s.

  The heat insulation class of electrical insulation is defined by the heat insulation class of electrical insulation and the heat resistance evaluation JEC-6147 (The Institute of Electrical Engineers of Japan, electrical standard survey standard), and the insulation materials used in compressors for refrigeration and air conditioners are also the above standards Selected by the heat-resistant species. However, since organic insulating materials for refrigeration and air-conditioning equipment are used in a special environment in a refrigerant atmosphere, it is necessary to consider suppressing deformation / denaturation due to pressure in addition to temperature. It also contacts polar compounds such as refrigerants and refrigerating machine oils, so solvent resistance, extraction resistance, thermal / chemical / mechanical stability, refrigerant resistance (crazing (after applying stress to the film, In addition, fine bellows-like cracks that occur when immersed in the film), blisters (film bubbles caused by temperature rise of the refrigerant absorbed in the film), etc. must also be taken into consideration.

  For this reason, it is necessary to use an insulating material of a high heat resistance class (E type 120 ° C. or higher).

  The insulating material most frequently used in the compressor is PET (polyethylene terephthalate). As a use, a film material is used for coil insulation with an iron core of a distributed winding motor, and a fibrous PET is used as a coil binding thread and a covering material for a lead wire of a motor.

  Other insulating films include PPS (polyphenylene sulfide), PEN (polyethylene naphthalate), PEEK (polyether ether ketone), PI (polyimide), PA (polyamide), and the like.

  The main insulation coating material for the coil is THEIC modified polyester, polyamide, polyamideimide, polyesterimide, polyesteramideimide, etc., and double coated copper wire with double coating of polyesterimide-amideimide is preferably used. The

  Even if a lubricity improver, an antioxidant, an acid scavenger, an antifoaming agent, a metal deactivator, or the like is added to the above refrigerating machine oil, there is no problem. In particular, since the polyol ester oil deteriorates due to hydrolysis in the presence of moisture, the blending of an antioxidant and an acid scavenger is essential.

  As the antioxidant, DBPC (2,6-di-t-butyl-p-cresol) which is a phenol type is preferable.

  As the acid scavenger, an aliphatic epoxy compound or a carbodiimide compound is generally used as a compound having an epoxy ring. In particular, carbodiimide compounds are extremely reactive with fatty acids and capture hydrogen ions dissociated from fatty acids, so the effect of suppressing the hydrolysis reaction of polyol ester oil is very large.

  Examples of the carbodiimide compound include bis (2,6-isopropylphenyl) carbodiimide. The compounding amount of the acid scavenger is preferably 0.05 to 1.0% by weight with respect to the refrigerating machine oil.

  In general, an extreme pressure agent may be mixed with the refrigerant used in the compressor. As extreme pressure agents, tertiary phosphates such as tricresyl phosphate and triphenyl phosphate are conventionally used.

  In the compressor for refrigerating and air-conditioning of the present invention, since the wear resistance can be improved by using the refrigerant and the refrigerating machine oil, it is not necessary to use an extreme pressure agent.

(Examples 1-12)
(Refrigerating machine oil component)
In order to increase the efficiency of a compressor for refrigeration and air conditioning, the dissolution viscosity (hereinafter simply referred to as “dissolution viscosity”) in a state where the refrigerant and the refrigeration oil are dissolved is an important factor.

  When a refrigerant having a low-temperature side critical solution temperature of −30 ° C. or less and refrigeration oil that begins to cause liquid-liquid two-layer separation at a low temperature is combined with the refrigeration oil depending on the compressor operating conditions, Decrease significantly. If the melt viscosity in the compressor is low, not only the sealing performance of the compression section will deteriorate, but also the oil film strength at the compressor sliding section will decrease, so wear will progress and the reliability of the refrigeration air conditioner will also decrease. End up. For this reason, the adsorptivity with respect to the sliding part of a refrigerator oil component becomes an important parameter.

  The sliding portion has many parts made of an iron-based material, and iron oxide is formed on the surface thereof.

  The adsorption capacity of the refrigerating machine oil to the iron-based material in this specification is considered to be substantially the adsorption capacity of the refrigerating machine oil to the iron oxide.

Based on this concept, in this example, the adsorption capacity of refrigerating machine oil was evaluated using powder (specific surface area 1.57 m ² / g) of Fe ₃ O ₄ (iron trioxide) having an average particle diameter of 1 μm. went.

  The concentration of the refrigerating machine oil component diluted in the solvent before and after adsorption was quantified by nuclear magnetic resonance analysis (NMR), and the amount adsorbed on the iron oxide powder was calculated. Hexane was used as the solvent, and each refrigerating machine oil component was adjusted to 0.3 mol-ppm. After 3 g of iron oxide powder was collected in a 20 ml screw tube, 10 g of a solution of a refrigerator oil component was added, dispersed in an ultrasonic cleaner for 30 minutes, and allowed to stand for 48 hours for 1H-NMR analysis of the supernatant.

  Here, mol-ppm is ppm (parts per million) on a molar basis. In other words, it is a percentage calculated using the number of moles of the solution (mixture of solvent and solute) as the denominator and the number of moles of the solute as the numerator.

  The base oil used as the refrigerating machine oil component is as follows. Here, 40 degreeC kinematic viscosity means kinematic viscosity in 40 degreeC.

(A) Hindered type polyol ester oil (POE) (pentaerythritol-based mixed fatty acid ester oil of 2-methylhexanoic acid / 2-ethylhexanoic acid): 40 ° C. kinematic viscosity 31.8 mm ² / s
(B) Hindered type polyol ester oil (POE) (neopentyl glycol / pentaerythritol-based 2-ethylhexanoic acid / 3,5,5-trimethylhexanoic acid mixed fatty acid ester oil): 40 ° C. kinematic viscosity 46.9 mm ² / s
(C) Hindered type polyol ester oil (POE) (neopentyl glycol / pentaerythritol-based 2-ethylhexanoic acid / 3,5,5-trimethylhexanoic acid mixed fatty acid ester oil): 40 ° C. kinematic viscosity 64.8 mm ² / s
(D) Hindered-type polyol ester oil (POE) (pentaerythritol-based 2-ethylhexanoic acid / 3, 5,5-trimethylhexanoic acid mixed fatty acid ester oil): 40 ° C. kinematic viscosity 91.3 mm ² / s
(E) Hindered type polyol ester oil (POE) (dipentaerythritol-based 2-ethylhexanoic acid / 3, 5,5-trimethylhexanoic acid mixed fatty acid ester oil): 40 ° C. kinematic viscosity 190 mm ² / s
(F) Hindered type polyol ester oil (POE) (dipentaerythritol-based 2-ethylhexanoic acid / 3, 5,5-trimethylhexanoic acid mixed fatty acid ester oil): 40 ° C. kinematic viscosity 217 mm ² / s
(G) Hindered type polyol ester oil (POE) (dipentaerythritol-based 3,5,5-trimethylhexanoic acid ester oil): 40 ° C. kinematic viscosity 417 mm ² / s
(H) Polyvinyl ether oil (PVE): 40 ° C. kinematic viscosity 50.1 mm ² / s
(I) Polyvinyl ether oil (PVE): 40 ° C. kinematic viscosity 65 mm ² / s
(J) Polyalkylene glycol oil (PAG) (polypropylene glycol dimethyl ether): 40 ° C. kinematic viscosity 112 mm ² / s
(K) Naphthenic mineral oil: 40 ° C kinematic viscosity 54.1 mm ² / s
(L) Poly α-olefin oil: 40 ° C. kinematic viscosity 61.8 mm ² / s
Table 1 shows the results of measuring the amount of the compound adsorbed on the iron oxide powder.

  The adsorption amount (adsorption ability) with respect to the iron oxide powder differs depending on each compound, and it is understood that the polar compound is more easily adsorbed to the iron-based material.

  It can be seen that even in polar compounds, compounds (E), (F) and (G) having a large number of ester groups in the molecular structure have a particularly large amount of adsorption. That is, (E), (F), and (G) have an adsorption capacity for iron-based materials (iron oxide) that is 2 compared to other refrigeration oil components (A) to (D) and (H) to (L). It can be seen that it is more than 0 times higher.

  From this, it is considered that the refrigerating machine oil components (E), (F), and (G) are likely to form a film in the compressor sliding portion.

  This is considered to be due to the following reason.

  The oxygen of carbonyl (C = O) contained in the ester group tends to be negatively charged. On the other hand, the surface of iron oxide is generally hydrated and has a structure having a hydroxyl group. For this reason, it is thought that the attractive force by a Coulomb force arises between the hydrogen contained in the hydroxyl group of the surface of iron oxide, and the oxygen contained in the ester group, and it becomes easy to adsorb | suck.

  From these results, (E), (F) and (G) were used as the added polyol ester oil in the present invention.

(Examples 13 to 25)
A refrigerant and refrigerating machine oil are enclosed in the compressor for refrigerating and air conditioning.

  The compatibility between the refrigerant and the refrigeration oil is an important characteristic for ensuring the reliability of the compressor, such as returning the oil from the refrigeration cycle to the compressor (securing the amount of oil inside the compressor) or reducing the heat exchange efficiency. one of. However, since there is a refrigerant, the melt viscosity of the mixed solution varies greatly depending on the amount of refrigerant in the refrigerating machine oil, and when the amount of penetration is large, the viscosity of the oil decreases significantly, and the sliding part has sufficient oil film strength. In addition, the function of the compression part as a sealing material is impaired.

  The evaluation of the compatibility between the refrigerant and the refrigerating machine oil was measured according to JIS K 2211.

  A refrigerant was sealed in a pressure-resistant glass container at an arbitrary oil concentration, and the contents were observed by changing the temperature. At this time, if the contents were cloudy, it was determined that the two layers were separated, and if the contents were transparent, it was determined to be dissolved. The oil concentration dependency of the temperature at which the two layers are separated is generally a curve having a maximum value. This maximum value was taken as the low temperature side critical dissolution temperature. The low temperature side critical dissolution temperature is a parameter indicating the degree of compatibility between the refrigerant and the refrigerating machine oil.

  Table 2 shows the results of selecting the refrigerating machine oil compatible with each refrigerant and measuring the low temperature side critical dissolution temperature.

  Depending on the degree of compatibility between the refrigerant and the refrigerating machine oil, the low temperature side critical dissolution temperature varies greatly. In particular, when HFO1234yf, propane, propylene, or fluoroethane is used as the refrigerant, the solubility in refrigerating machine oil is very high, causing a significant decrease in viscosity under compressor operating conditions. Usually, the viscosity grade of refrigerating machine oil is raised, but under the operating conditions of the compressor for refrigerating and air conditioning, the amount of dissolved refrigerant increases with temperature and pressure, and the viscosity does not increase much in practice.

(Examples 26-31, Comparative Examples 1-6)
The lubricity of refrigeration oil was evaluated using a shell-type four-ball frictional wear tester.

  Wear mark diameter (average of 3 pieces) and friction of a fixed test piece after being tested with a 1/2 inch SUJ2 steel ball as a test piece, load: 280 N, temperature: 120 ° C., rotation speed: 1200 / min, time: 10 min The coefficient was measured.

  As the refrigerating machine oil main component, polyol ester oils (A) to (D), polyvinyl ether oil (I), and naphthenic mineral oil (K) are used, and added polyol ester oil (F) is blended at 5.0 wt%. Evaluated.

  As comparative examples, the case of each of the polyol ester oils (A) to (D), the case of the polyvinyl ether oil (I) alone and the case of the naphthenic mineral oil (K) alone were evaluated.

  Table 3 shows the results of evaluating the lubricity of each refrigeration oil.

  From this result, the refrigerating machine oils of Comparative Examples 1 to 4 in which the added polyol ester oil (F) is not blended have a large wear scar diameter and a high friction coefficient. In the case of Comparative Examples 5 and 6, since the seizure occurred immediately after the start of the test, the test was interrupted.

  On the other hand, the refrigerating machine oil blended with the added polyol ester oil (F) shown in Examples 26 to 31 has a reduced wear scar diameter and a coefficient of friction regardless of the oil type of the refrigerating machine oil main component, and has a lubricating property. The improvement effect was obtained. This is because the adsorption capacity of the added polyol ester oil (F) to the iron-based material is greater than that of the main component of the refrigeration oil, so that the friction surface is reduced in surface energy, and the effect of reducing wear resistance and friction coefficient is obtained. by. The refrigerator oil main component did not cause seizure even in the polyvinyl ether oil (I) and the naphthenic mineral oil (K). In particular, as shown in Table 1, when the main component of the refrigerating machine oil is a polyvinyl ether oil (I) or a naphthenic mineral oil (K) having a smaller adsorption amount than the added polyol ester oil (F), the added polyol ester oil (F ) Tends to be adsorbed on the friction surface, and the effect of improving lubricity is easily obtained.

(Examples 32-37, Comparative Examples 7-8)
In order to confirm the effects of the added polyol ester oils (E) and (G), the same test as in Example 26 was performed using a shell-type four-ball frictional wear tester and changing the type and added amount of the added polyol ester oil. did.

  Table 4 shows the results of evaluating the lubricity of each refrigeration oil.

  The refrigerating machine oils of Examples 32 to 37 shown in this table use (C) as a refrigerating machine oil main component, and wear scar diameter and friction as compared with the refrigerating machine oil of Comparative Example 3 (shown in Table 3) to which no additive is added. The coefficient was suppressed, and the improvement effect of lubricity could be confirmed.

  In Comparative Examples 7 and 8, in which the added amount of the added polyol ester oil (F) is small, the wear scar diameter is large, the friction coefficient is high, and the effect of improving the lubricity is hardly exhibited. On the other hand, the refrigerating machine oil in which the additive polyol ester oil (F) shown in Examples 32-35 is blended in an amount of 1.0% by weight or more with respect to the refrigerating machine main agent has a reduced wear scar diameter and a friction coefficient. The effect of improving lubricity was obtained.

(Examples 38 and 39, Comparative Examples 9 and 10)
FIG. 1 shows an outline of a room air conditioner that is also used in the present embodiment.

  When the room is cooled, the high-temperature and high-pressure refrigerant gas (encapsulated refrigerant) compressed adiabatically from the discharge pipe of the compressor 1 passes through the four-way valve 2 in the outdoor heat exchanger 3 (used as a condensing means). It is cooled and becomes a high-pressure liquid refrigerant. This refrigerant is expanded by expansion means 4 (for example, a capillary tube or a temperature type expansion valve, which is also referred to as a decompression section), and becomes a low-temperature and low-pressure liquid containing a slight amount of gas to form an indoor heat exchanger 5 (evaporation means). To obtain the heat from the indoor air and reach the compressor 1 again through the four-way valve 2 in the state of low-temperature gas. When the room is heated, the flow of the refrigerant is changed in the reverse direction by the four-way valve 2, and the reverse action occurs.

  In this embodiment, a scroll compressor is used as the compressor.

  FIG. 2 shows the schematic structure.

  The compressor wraps a spiral wrap 8 standing upright on an end plate 7 of the fixed scroll member 6 and a revolving scroll member 9 having a wrap 10 having substantially the same shape as the fixed scroll member 6 and the wrap 8. 10 and facing each other to form a compression mechanism, and the orbiting scroll member 9 is orbited by the crankshaft 11. Of the compression chambers 12a and 12b formed by the fixed scroll member 6 and the orbiting scroll member 9, the outermost compression chamber orbits with the fixed scroll member 6 while the volume gradually decreases with the orbiting motion. It moves toward the central part constituted by the scroll member 9. When the compression chambers 12a and 12b reach the vicinity of the central portion formed by the fixed scroll member 6 and the orbiting scroll member 9, the compression chambers 12a and 12b communicate with the discharge port 13 and the compression inside the compression chambers 12a and 12b. Gas is discharged from the discharge pipe 16 to the outside of the compressor.

  In the compressor of the present embodiment, an electric motor 17 is built in the pressure vessel 15, and the compressor has the crankshaft 11 at a constant speed or a rotational speed corresponding to a voltage controlled by an inverter not shown. Rotates and performs compression. An oil sump 20 is provided below the motor 17, and the oil in the oil sump 20 passes through an oil hole 19 provided in the crankshaft 11 due to a pressure difference, and the orbiting scroll member 9 and the crankshaft 11. And is used for lubricating the sliding portion and the sliding bearing 18 and the like.

  In Examples 38 and 39 and Comparative Examples 9 and 10, an actual machine test was performed in which the indoor unit was installed in a temperature-controlled room (35 ° C., humidity 75%) and operated for 2160 hours using the room air conditioner shown in FIG. .

  A heat-resistant PET film (Type B 130 ° C.) was used for coil insulation with the iron core of the motor 17, and a double coated copper wire coated with polyesterimide-amideimide was used for the coil main insulation.

  For the evaluation of the room air conditioner, the amount of increase in the gap due to wear between the frame 14 and the crankshaft 11 (between the frame 14 and the crankshaft 11) was measured before and after the test, focusing on the worn state of the scroll compressor. This shows that the amount of wear increases as the amount of increase in the gap between the frame 14 and the crankshaft 11 (hereinafter also referred to as “between the frame and the shaft”) increases. In general, vibration and noise increase as the amount of increase in the gap increases. Become.

  HFO1234yf (2, 3, 3, 3-tetrafluoropropene) was used alone as a refrigerant. HFO1234yf is a low-pressure refrigerant, and since the refrigerant circulation amount is small, the pressure loss in the pipe increases. For this reason, the amount of pushing away from the compressor was doubled as usual, and the evaluation was made with the specifications in which the diameter of the connecting pipe was increased, the number of heat exchanger paths was increased, and the distribution balance was adjusted.

  In the refrigerating and air-conditioning cycle using HFO1234yf and HFO1234ze and a mixed refrigerant containing these, the compatibility between the refrigerant and the refrigerating machine oil is an important characteristic for ensuring the amount of oil return to the compressor. In the refrigerating and air-conditioning cycle, it is necessary to circulate refrigerating machine oil as well as refrigerant. If the compatibility is inferior, the refrigerating machine oil discharged by the mechanical elements from the compressor will not circulate, and the oil separated especially at the low temperature part will stay, so the amount of oil in the compressor will decrease, and the lubricating oil in the sliding part It will cause trouble. For this reason, it is preferable that the refrigerant and the refrigerating machine oil are dissolved in the operating condition temperature range in the cycle.

  Since hydrocarbon oils such as naphthenic mineral oil, paraffinic mineral oil, alkylbenzene oil, and poly-α-olefin oil are less compatible with HFO1234yf, polyol ester oil or polyvinyl ether oil is preferable.

  In Example 38, evaluation was performed using the refrigerating machine oil ((C) + (F)) employed in Example 28 having compatibility with HFO1234yf. In Example 39, evaluation was performed using the refrigerating machine oil ((I) + (F)) employed in Example 30.

(C) or (I) is used as the refrigerating machine oil main component, and 5% by weight of (F) having a high adsorption capacity is blended with them, and the kinematic viscosity at 40 ° C. is 68.6 mm ² / s or 68.9 mm ² The test was carried out with a refrigerating machine oil of / s.

  In Comparative Examples 9 and 10, it was carried out only with the refrigerating machine oil main agent in which the added polyol ester oil was not blended in Examples 38 and 39.

  The target value of this test is that the amount of increase in the gap due to wear between the frame and the shaft after the test is 10 μm or less.

  The results of Examples 38 and 39 and Comparative Examples 9 and 10 are shown in Table 5.

  As is apparent from Table 5, the room air conditioners of Examples 38 and 39 can greatly reduce the amount of increase in the gap between the frame and the shaft, and suppress wear, compared with Comparative Examples 9 and 10. High reliability can be obtained.

  Table 5 also shows the measurement results of the viscosity and efficiency in the cooling intermediate condition regarding the combination of the refrigerant and the refrigerating machine oil.

  The viscosity was measured using a piston viscometer manufactured by Japan Control.

  The efficiency was expressed as a ratio using the coefficient of performance (COP) as a reference (100) with Comparative Example 9 as the reference.

  From this result, in Comparative Examples 9 and 10, a decrease in viscosity occurs, and a sufficient sealing performance cannot be obtained in the compressed portion. On the other hand, in Examples 38 and 39, the viscosity is increased.

  Furthermore, as shown in Examples 28 and 30 of Table 3, the coefficient of performance was improved as compared with Comparative Example 9 (Criteria 1) because the friction suppressing effect of the added polyol ester oil was exhibited.

  From the results of the above examples, it was found that a refrigeration air conditioner capable of suppressing compressor wear and sufficiently ensuring long-term insulation reliability can be obtained.

  Although not shown, the same applies to the combination of the refrigerant mixture of HFO1234yf and HFC32 (20 wt% and 40 wt%) and the refrigerating machine oil ((C) + (F)) employed in Example 28. Although evaluation was performed in an actual machine test, almost the same results as in Examples 38 and 39 were obtained, and it was confirmed that even if a mixed refrigerant was used, the effect was obtained and there was no problem.

(Examples 40 to 42, Comparative Examples 11 to 13)
In Examples 40 to 42, propane and R410A were used as refrigerants, and refrigeration cycles suitable for the respective refrigerants were assembled, and evaluation was performed in the same actual machine test as in Example 38.

  In Example 40, propane was used as the refrigerant, (C) as the refrigerating machine main agent, and refrigerating machine oil blended with 5.0 wt% of (F) as the added polyol ester oil.

  In Example 41, propane was used as the refrigerant, (K) as the refrigerating machine main agent, and refrigerating machine oil blended with 5.0 wt% of (F) as the added polyol ester oil.

  In Example 42, R410A was used as the refrigerant, (C) as the refrigerating machine main agent, and refrigerating machine oil blended with 5.0 wt% of (F) as the added polyol ester oil.

  In Comparative Examples 40 to 42, refrigerating machine oils not containing any added polyol ester oil were evaluated.

  The evaluation results are shown in Table 5.

  As shown in the compatibility evaluation results in Table 2, propane is highly soluble in polyol ester oils, mineral oils, and the like, and causes a significant viscosity reduction in the compressor. Further, since no halogen element is contained in the molecular structure, iron halide that contributes to lubricity in a site where friction occurs is not generated, and therefore, as shown in Comparative Examples 11 and 12, an increase in the gap due to wear between the frame and the shaft. The amount will increase significantly.

  On the other hand, as shown in Examples 40 and 41, with respect to the combination in which the additive polyol ester oil (F) is blended with the refrigerating machine main agent, the increase in gap due to wear between the frame and the shaft is greatly reduced, and the friction As a result, the coefficient of performance was improved as compared with Comparative Example 11 (Criteria 2).

  Further, in Example 42 using R410A as the refrigerant, an increase in gap due to wear between the frame and the shaft was suppressed and the coefficient of performance was improved as compared with Comparative Example 13 (Reference 3).

  For this reason, the same effect can be obtained with refrigerants such as difluoromethane, fluoroethane, and propylene, regardless of the type of refrigerant.

  In addition, the same effect can be obtained in a rotary compressor, a twin rotary compressor, a two-stage compression rotary compressor, and a swing compressor in which rollers and vanes are integrated.

  The present invention is applicable to a refrigerant compressor for a refrigeration air conditioner and a refrigeration air conditioner.

  1: compressor, 2: four-way valve, 3: outdoor heat exchanger, 4: expansion means, 5: indoor heat exchanger, 6: fixed scroll member, 7: end plate, 8: wrap, 9: orbiting scroll member, 10: lap, 11: crankshaft, 12a, 12b: compression chamber, 13: discharge port, 14: frame, 15: pressure vessel, 16: discharge pipe, 17: electric motor, 18: sliding bearing, 19: oil hole, 20: Oil sump part.

Claims (8)

A refrigerant containing 2,3,3,3-tetrafluoropropene, 1,3,3,3-tetrafluoropropene or difluoromethane or an enclosed refrigerant which is R410A is represented by the following chemical formulas (1) and (2). Refrigerating machine oil main ingredient containing at least one kind of base oil selected from the group consisting of polyol ester oil (wherein R ₁ represents an alkyl group having 5 to 9 carbon atoms), and represented by the following chemical formula (3) A compressor for refrigerating and air-conditioning in which a refrigerating machine oil containing and added polyol ester oil (wherein R ₂ represents an alkyl group having 7 to 9 carbon atoms) is enclosed, A compressor for refrigerating and air-conditioning having a composition of 1 to 30% by weight.

An encapsulated refrigerant, which is a refrigerant containing 2,3,3,3-tetrafluoropropene, 1,3,3,3-tetrafluoropropene, propane, propylene, or fluoroethane, contains mineral oil or polyvinyl ether oil or the following chemical formula (1) And at least one base oil selected from the group consisting of polyol ester oils represented by (2) (wherein R ₁ represents an alkyl group having 5 to 9 carbon atoms). A refrigerating machine oil containing a refrigerating machine oil main component having a temperature of −30 ° C. or less and an added polyol ester oil represented by the following chemical formula (3) (wherein R ₂ represents an alkyl group having 7 to 9 carbon atoms). A compressor for refrigerating and air-conditioning, which is mixed and sealed, wherein the composition of the added polyol ester oil is 1 to 30% by weight.

The kinematic viscosity at 40 ° C. of the refrigerating machine oil base resin is in the range of 25~120mm ² / s, according to claim 1 kinematic viscosity at 40 ° C. of the additive polyol ester oil is equal to or is 180 mm ² / s or more or The compressor for refrigerating and air-conditioning according to claim 2.   From the refrigeration / air conditioning compressor according to any one of claims 1 to 3, a heat exchanger for radiating heat of the enclosed refrigerant discharged from the refrigeration / air conditioning compressor, and the heat exchanger A refrigerating and air-conditioning apparatus comprising: a decompression unit for decompressing the enclosed refrigerant flowing out; and a heat exchanger for heating the enclosed refrigerant decompressed by the decompression unit. The refrigerating machine oil main agent has a kinematic viscosity at 40 ° C. of 25 to 120 mm ² / s, and the adsorption ability of the added polyol ester oil to the iron-based material is twice or more higher than that of the refrigerating machine oil main agent. The refrigeration air conditioner according to claim 4. A polyol ester oil represented by the following chemical formulas (1) and (2) (wherein R ₁ has 5 to 9 carbon atoms) is added to a refrigerant having a global warming potential of 1000 or less, or a refrigerant for refrigerating and air conditioning that is R410A. A refrigerating machine oil main agent having at least one base oil selected from the group consisting of an alkyl group and having a kinematic viscosity at 40 ° C. of 25 to 120 mm ² / s, and an addition represented by the following chemical formula (3) A compressor for refrigerating and air conditioning in which a refrigerating machine oil containing a polyol ester oil (wherein R ₂ represents an alkyl group having 7 to 9 carbon atoms) is mixed and enclosed, and the composition of the added polyol ester oil is A compressor for refrigeration and air conditioning characterized by being 1 to 30% by weight.

  The compressor for refrigerating and air conditioning according to claim 6, a heat exchanger for dissipating heat of the refrigerant for refrigerating and air conditioning discharged from the compressor for refrigerating and air conditioning, and the compressor for refrigerating and air conditioning flowing out from the heat exchanger A refrigerating and air-conditioning apparatus comprising: a decompression unit for decompressing a refrigerant; and a heat exchanger for heating the refrigerating and air-conditioning refrigerant decompressed by the decompression unit. The refrigerating machine oil main agent has a kinematic viscosity at 40 ° C. of 25 to 120 mm ² / s, and the adsorption ability of the added polyol ester oil to the iron-based material is twice or more higher than that of the refrigerating machine oil main agent. The refrigerating and air-conditioning apparatus according to claim 7.

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