JPH09303278A - Refrigerating compressor and refrigerating air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To restrain the appearance of a decomposable product insoluble in a coolant by using ether oil or the like as oil for coating the parts of a refrigerating compressor, regarding the refrigerating compressor where hydro- fluorocarbon is used as a coolant and ester oil or the like as refrigerator oil. SOLUTION: A totally enclosed reciprocating compressor draws a coolant returned from an evaporator, through a suction port 1 and then converts the rotating motion of an electric motor 3 into the reciprocating motion of a piston with a crankshaft 4 through a connecting rod 5. The coolant is thereby drawn into a cylinder 7 and raised in pressure. Thereafter, the coolant is discharged from a delivery port 2. Also, hydro-fluorocarbon is used as the coolant, and at least one of ester oil, ether oil and carbonate oil is used as refrigerator oil. In this case, ether oil and/or carbonate oil is used as an oil applied to compressor parts. Thus, the oil and the coolant are dissolved into each other, thereby preventing the deterioration of a refrigerating function due to the flow of the refrigerator oil to a refrigeration cycle.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigerating compressor and a refrigerating and air-conditioning apparatus that use hydrofluorocarbon as a refrigerant.

[0002]

2. Description of the Related Art An example of a conventional refrigeration compressor is shown in FIG.
FIG. 1 shows an example of a fully enclosed reciprocating compressor.
The refrigerant returned from the evaporator side is sucked in, and the rotary motion of the electric motor 3 is converted into reciprocating motion by the connecting rod 5 via the crankshaft 4, and the piston 6 driven by this converts it into / from the cylinder 7. The refrigerant is sucked / discharged, and the high-pressure refrigerant gas is discharged from the discharge port 2.

An example of another conventional refrigeration compressor is shown in FIG. FIG. 2 shows an example of a rotary compressor, which has an accumulator 11 for sucking the refrigerant returned from the evaporator side in a vaporized state without fail.
More directly, it is sucked into the cylinder 7, and the rotary motion of the electric motor 3 is compressed by the rolling piston 12 which makes eccentric rotary motion via the shaft 13 and is discharged into the compressor. Then, the high-pressure refrigerant gas is discharged from the discharge port 2.

FIG. 3 shows an example of another conventional refrigeration compressor. FIG. 3 shows an example of a scroll compressor, which sucks directly into the cylinder constituted by the gap between the fixed scroll 14 and the orbiting scroll 15 from the suction port 1 to orbit the rotary motion of the electric motor 3 via the shaft 13. Along with the movement of the orbiting scroll 15, the clearance between the orbiting scroll 15 and the fixed scroll 14 is reduced to compress the refrigerant and discharge it into the compressor.
Then, the high-pressure refrigerant gas is discharged from the discharge port 2.

In various refrigerant compressors as described above, bearing portions such as crankshafts and shafts, especially rolling bearings as auxiliary bearings are often provided. An oil pump may be provided to supply oil to the sliding portion.

[0006] For the purpose of preventing rust and smoothly performing the initial operation, as the oil to be applied to the parts of these refrigerating compressors and the oil to be used at the time of assembling the refrigerating compressor, conventionally, greases and various additives have been added. Alternatively, additive-free mineral oil has been used.

Further, in the totally hermetic refrigerant compressor, an electric motor is provided inside the shell. Insulation-coated copper wire is wound around the stator of the motor to form a coil.In the process of forming this winding, mineral oil with or without various additives is applied to prevent damage to the insulation-coated copper wire. Was there.

Next, an example of a conventional refrigerating and air conditioning system is shown in FIG.
Shown in The high-pressure gas refrigerant discharged from the refrigeration compressor 17 is condensed in the condenser 19, passes through the expansion mechanism 20 and moves to a low pressure, is vaporized in the evaporator 21, and returns to the refrigeration compressor.

On the other hand, as refrigerants for refrigerating air conditioners such as refrigerators, room air conditioners, and package air conditioners, chlorofluorocarbons (CFCs) such as dichlorodifluoromethane (R12) and monochlorodifluoromethane (R12).
22) and other hydrochlorofluorocarbons (HCF
C) type refrigerants have been widely used.

However, these chlorine-containing refrigerants destroy the ozone layer of the earth's stratosphere and promote the harmful ultraviolet rays to pour onto the earth. Therefore, most CFC-based refrigerants already have a relatively small ozone depletion coefficient. It has been determined by international regulations that HCFC refrigerants will be completely abolished in 2020.

Instead of these conventional refrigerants, hydrofluorocarbon (HFC) type refrigerants such as 1,1,1,
2-tetrafluoroethane (R134a), difluoromethane (R32), pentafluoroethane (R125)
Or R410A or R as a mixed refrigerant of these
Refrigerants such as 407C have been proposed, studied, or already used as alternative refrigerants.

Hydrofluorocarbon refrigerants having no chlorine atom in the molecule have a molecular polarity larger than that of the conventional refrigerants, and therefore, nonpolar refrigerating machine oils such as mineral oils, alkylbenzenes and poly α-olefins which have been used together with the conventional refrigerants. Is poorly compatible, and has been proposed, studied, or already implemented for use with polar oils such as polyalkylene glycol, ester, ether, and carbonate, which are compatible with each other.

On the other hand, contrary to the above, a refrigeration cycle using a low-viscosity refrigerating machine oil that is incompatible with the refrigerant and improving the oil return of the refrigerating machine oil discharged from the compressor together with the refrigerant to the compressor, A refrigerating compressor in which a low-viscosity oil that is incompatible with a refrigerant is used when assembling the refrigerating compressor has also been proposed (Japanese Patent Laid-Open No. 5-157379).

[0014]

Despite the refrigeration cycle using the HFC refrigerant, greases are used as the oil to be applied to the parts of the refrigeration compressor and the oil to be used when assembling the refrigeration compressor, as in the conventional case. When mineral oils with or without various additives are used, they do not mutually dissolve with the refrigerant, so they accumulate in the liquid pool in the refrigeration cycle, and the cross-sectional area of the refrigerant flow path such as the capillary tube or electric expansion valve is reduced. There is a problem in that a small area may adhere to and accumulate on the tube wall, resulting in deterioration of the refrigerating capacity and impairing the original function of the liquid pool.

On the other hand, in the method as disclosed in Japanese Unexamined Patent Publication No. 5-157379, since the refrigerating machine oil is a chemically stable hydrocarbon oil, a decomposed product which is not sufficiently dissolved in the HFC refrigerant is produced. Although there is no problem to do, since the thermal conductivity of the refrigerating machine oil is smaller than the thermal conductivity of the refrigerant,
The circulation of the refrigeration oil refrigeration cycle impedes heat conduction on the pipe wall, resulting in a problem that the refrigeration capacity is not fully exerted.

The present invention takes into consideration such problems of the conventional refrigeration compressor, does not reduce the refrigerating capacity due to circulation of refrigeration oil to the refrigeration cycle, and the amount of water in the refrigerant circulating in the refrigeration cycle. It is possible to provide a refrigerating compressor and a refrigerating air-conditioning device that can reduce the choking phenomenon due to moisture, can suppress hydrolysis, and consequently can suppress the generation of decomposition products that do not dissolve in the refrigerant. It is intended.

[0017]

The present invention is a refrigerating compressor which uses hydrofluorocarbon as a refrigerant and at least one of ester oil, ether oil and carbonate oil as a refrigerating machine oil, and is applied to parts of the refrigerating compressor. Ether oil and / or carbonate oil is used as the oil used or the oil used when assembling the refrigeration compressor.

In particular, the refrigeration compressor has a rolling bearing,
Further, the effect is remarkable when the component of the refrigerating compressor is a rolling bearing, or when the component of the refrigerating compressor has an oil pump and the component of the refrigerating compressor is an oil pump.

Further, the refrigerating compressor has a built-in electric motor, and ether oil and / or carbonate oil is used as a coating oil for the insulating film electric wire in the winding step.

Alternatively, in a refrigerating and air-conditioning apparatus using hydrofluorocarbon as a refrigerant and at least one of ester oil, ether oil and carbonate oil as a refrigerating machine oil, oil applied to parts of a refrigerating compressor or assembly of the refrigerating compressor. As the oil sometimes used, ether oil and / or carbonate oil is used, and the refrigerating machine oil contains a water trapping additive.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. The present invention, hydrofluorocarbon as a refrigerant, ester oil as a refrigerator oil,
In a refrigeration compressor using at least one of ether oil and carbonate oil, ether oil and / or carbonate oil is used as an oil to be applied to parts of the refrigeration compressor or an oil used in assembling the refrigeration compressor. It is a substance, and as a result, it mutually dissolves with the refrigerant
There is no reduction in refrigeration capacity due to circulation of refrigeration oil to the refrigeration cycle.

The hydrofluorocarbon in the present invention has 1 to 1 carbon atoms which can be used for refrigeration and air conditioning.
It is a hydrocarbon in which about 3 hydrogen atoms are partially replaced with fluorine atoms. Specifically, fluoromethane, difluoromethane, trifluoromethane, fluoroethane, 1,
1-difluoroethane, 1,2-difluoroethane,
1,1,1-trifluoroethane, 1,1,2-trifluoroethane, 1,1,1,2-tetrafluoroethane, 1,1,2,2-tetrafluoroethane, pentafluoroethane, 1- Fluoropropane, 2-fluoropropane, 1,1-difluoropropane, 1,2-difluoropropane, 1,3-difluoropropane, 1,1,
1-trifluoropropane, 1,1,2-trifluoropropane, 1,1,3-trifluoropropane, 1,
2,3-trifluoropropane, 1,2,2-trifluoropropane, 1,1,1,2-tetrafluoropropane, 1,1,2,2-tetrafluoropropane, 1,
1,1,3-tetrafluoropropane, 1,1,2,3
-Tetrafluoropropane, 1,1,3,3-tetrafluoropropane, 1,2,2,3-tetrafluoropropane, 1,1,1,2,2-pentafluoropropane,
1,1,2,2,3-pentafluoropropane, 1,
1,2,3,3-pentafluoropropane, 1,1,
1,2,3-pentafluoropropane, 1,1,1,
3,3-pentafluoropropane, 1,1,1,2,
2,3-hexafluoropropane, 1,1,2,2
3,3-hexafluoropropane, 1,1,1,3
Mention may be made of 3,3-hexafluoropropane.

Examples of the ester oil in the present invention include oils having a base oil of polyol ester, dibasic acid ester, complex ester and the like.

Of these, as the polyol ester,
An ester of a diol or a polyol having 3 to 20 hydroxyl groups and a fatty acid having 6 to 20 carbon atoms is preferably used.

As the diol, those having 2 to 12 carbon atoms are preferable, and specific examples thereof include ethylene glycol, 1,3-propanediol, propylene glycol, and 1,4-butanediol. , 1,2-butanediol, 2-methyl-1,3-propanediol, 1,5
-Pentanediol, Neopentyl glycol, 1,6
-Hexanediol, 2-ethyl-2-methyl-1,3
-Propanediol, 1,7-Heptanediol, 2-
Methyl-2-propyl-1,3-propanediol,
2,2-diethyl-1,3-propanediol, 1,8
-Octanediol, 1,9-nonanediol, 1,1
0-decanediol, 1,11-undecandiol,
1,12-dodecanediol and the like.

The polyol preferably has 3 to 60 carbon atoms, and specific examples thereof include trimethylolethane, trimethylolpropane, trimethylolbutane, di- (trimethylolpropane), and tri- (trimethylolpropane). ), Pentaerythritol, di- (pentaerythritol), tri- (pentaerythritol)
), Glycerin, polyglycerin (2- to 2-glycerin)
20-mer), 1,3,5-pentantriol, sorbitol, sorbitan, sorbitol-glycerin condensate,
Polyhydric alcohols such as adonitol, arabitol, xylitol, mannitol, xylol, arabinose, ribose, rhamnose, glycose, fructose, galactose, mannose, sorbose, cellobiose, maltose, isomaltose, trehalose, sucrose , Raffinose, gentianose, melezitose and the like, and partial ether compounds thereof, methyl glycoside (glycoside) and the like.

Specific examples of the fatty acid include hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, undecanoic acid, dodecanoic acid, tridecanoic acid, tetradecanoic acid, pentadecanoic acid, hexadecanoic acid, heptadecanoic acid, octadecane. Examples thereof include straight-chain or branched acids such as acids, nonadecanoic acid, eicosanoic acid, and oleic acid, and so-called neo acids having a quaternary α carbon atom.

The polyol ester may have a free hydroxyl group. Incidentally, particularly preferred polyol esters are neopentyl glycol, trimethylolethane, trimethylolpropane, trimethylolbutane,
Esters of hindered alcohols such as di- (trimethylolpropane), tri- (trimethylolpropane), pentaerythritol, di- (pentaerythritol) and tri- (pentaerythritol). . Specific examples include trimethylol propane caprylate, trimethylol propane largonate, pentaerythritol hexanoate, pentaerythritol 2-ethylhexanoate, and pentaerythritol pelargonate.

As the dibasic acid ester, glutaric acid,
Adipic acid, pimelic acid, suberic acid, azelaic acid,
C5-10 dibasic acids such as sebacic acid and methanol, ethanol, propanol, butanol, pentanol, hexanol, heptanol, octanol, nonanol, decanol, undecanol, dodecanol, tridecanol, tetradecanol, pentadecanol, etc. C 1 having a linear or branched alkyl group of
Esters with a monohydric alcohol of from 15 to 15 are preferably used. Specific examples include ditridecyl glutarate, di-2-ethylhexyl adipate, diisodecyl adipate, ditridecyl adipate, and di-3-ethylhexyl sebacate.

The complex ester is a mixture of esters of fatty acid or dibasic acid and monohydric alcohol or polyol, and the mixing ratio thereof is not particularly limited. As fatty acids, dibasic acids, monohydric alcohols and polyols, those similar to those exemplified for the polyol ester and the dibasic ester can be used.

As the ether oil, in addition to polyalkylene glycol and its partially modified oil, known materials such as polyether oil and polyvinyl ether oil can be mentioned (JP-A-6-240278 and JP-A-7-118).
674, and Japanese Patent Application Laid-Open No. 7-179877).

Examples of the carbonate oil include known materials such as polyol carbonic acid ester (JP-A-4-18490 and JP-A-4-57893,
JP-A-4-63893, JP-A-3-149295
Japanese Patent Laid-Open No. 3-247695, Japanese Patent Laid-Open No. 4-6
3893, JP 4-139154 A, JP 4-139155 A, JP 4-178354 A, JP 4-331289 A, JP 5-32 A.
688, JP-A-5-51689, JP-A-5
-86381, JP-A-5-86391, JP-A-5-98277, JP-A-5-125375, JP-A-5-132685, and JP-A-5-14.
No. 0572, Japanese Patent Laid-Open No. 5-186784, Japanese Patent Laid-Open No. 5-1994968, Japanese Patent Laid-Open No. 5-255680, Japanese Patent Laid-Open No. 5-229590, and Japanese Patent Laid-Open No. 5-33.
9592, JP-A-6-87791, JP-A-6-87792, JP-A-6-166884, JP-A-7-157883, and JP-A-7-233.
386).

Rolling bearings can be mentioned as an example of the components of the refrigerating compressor according to the present invention, and more specifically, ball bearings, needle roller bearings, cylindrical roller bearings, tapered roller bearings, radial needle roller bearings. Etc.

As the oil to be applied to these rolling bearings,
By using the ether oil and / or carbonate oil as described above, rust prevention and smoothness in the initial operation can be ensured.

An oil pump can be cited as another example of the parts of the refrigeration compressor in the present invention. The oil pump includes one that conveys oil by centrifugal force, one that conveys oil mechanically, and one that conveys oil by using a capillary phenomenon in some cases.

Another example of the parts of the refrigerating compressor according to the present invention is an insulating coated copper wire of an electric motor.

In all of these refrigeration compressor parts, a relatively large amount of oil adheres when oil is applied or when it is used during assembly due to the large cavities and large surface area of the whole parts. By using an ether oil and / or a carbonate oil instead of the conventional grease or mineral oil, it is possible to prevent the insoluble component from being mixed in the hydrofluorocarbon refrigerant.

Further, ether oils and / or carbonate oils are more likely to absorb water than mineral oils and alkylbenzene oils, but their saturated water absorption is about several thousand ppm by weight, and at most about 1%.

Since the total amount of application and adhesion of the ether oil and / or carbonate oil is not extremely large, the ether oil and / or carbonate adhered by the heating and drying step at the time of baking coating of the exterior which is usually carried out at the time of assembling the refrigeration compressor. Since the contribution of the water absorbed by the oil to the residual water inside the refrigeration compressor is sufficiently small, there is no effect even when an ester oil that is not highly stable against water is used as the refrigerator oil.

Further, by equipping a refrigerating air conditioner such as a room air conditioner, a multi air conditioner, a package air conditioner, a car air conditioner, a freezer, a refrigerator, a showcase, etc. with a moisture adsorbing device, even in the manufacturing process of the refrigerating compressor as described above. Even if the removal of water is not sufficient, the amount of water in the refrigerant circulating in the refrigeration cycle can be reduced, so not only can the choking phenomenon due to water be prevented, but an ester-based product that can produce a decomposition product that does not dissolve in the refrigerant. Even if refrigerating machine oil is used, hydrolysis can be suppressed, and as a result, decomposition products that do not dissolve in the refrigerant can be suppressed from being generated. Examples of the water adsorption device in the present invention include a so-called drier in which a desiccant using a conventionally used granular or plate-shaped alumina or zeolite is filled in a metal container, but other drying Examples of the agent include silica gel and water-absorbing organic polymer gel. The moisture adsorbing device 22 is installed at a high pressure part of a liquid or gas-liquid two phase between the condenser 19 and the evaporator 21 as shown in FIG. 5 or a gas phase part so that a large pressure loss is not generated by the installation. Even if there is, the flow cross section of the refrigerant is large and the flow is not hindered by the installation.
Alternatively, it is preferable to provide the accumulator 11 as shown in FIG. The other parts in FIGS. 5, 6, and 7 are the same as those in FIG. 4, and therefore, the same numbers are given and the description thereof is omitted.

Similarly, since the refrigerating machine oil contains a water trapping additive, the water content of the refrigerant circulating in the refrigeration cycle can be reduced, and the choking phenomenon due to the water can be prevented. Even if an ester-based refrigerating machine oil that can generate a decomposition product that does not dissolve in water is used, hydrolysis can be suppressed, and as a result, generation of a decomposition product that does not dissolve in the refrigerant can be suppressed. Examples of the water scavenger of the present invention include epoxy compounds such as phenyl glycidyl ether, which have been conventionally used as acid water scavengers for refrigerating machine oil. As the water scavenger other than these, organoalkoxysilanes used as a water scavenger for removing water during construction of an air conditioner can be used. This is preferable because it has a higher water trapping property.

[0042]

As is apparent from the above description,
According to the present invention, since the oil and the refrigerant are mutually dissolved, the refrigerating capacity does not decrease due to the circulation of the refrigerating machine oil to the refrigerating cycle.

Water is more easily absorbed than mineral oil or alkylbenzene oil, but the total amount of coating / adhesion is not large.
By equipping the refrigeration cycle with a water adsorption device, the amount of water in the refrigerant circulating in the refrigeration cycle can be reduced, and not only can the choking phenomenon due to water be prevented, but decomposition products that do not dissolve in the refrigerant can also be generated. Hydrolysis can be suppressed even when an ester-based refrigerating machine oil is used, and as a result, generation of a decomposition product that does not dissolve in the refrigerant can be suppressed.

Similarly, since the refrigerating machine oil contains the water trapping additive, the water content of the refrigerant circulating in the refrigeration cycle can be reduced, and the choking phenomenon due to the water can be prevented. Even if an ester-based refrigerating machine oil that can generate a decomposition product that does not dissolve in water is used, hydrolysis can be suppressed, and as a result, generation of a decomposition product that does not dissolve in the refrigerant can be suppressed.

[Brief description of drawings]

FIG. 1 is a diagram showing an example of a conventional refrigeration compressor.

FIG. 2 is a diagram showing another example of a conventional refrigeration compressor.

FIG. 3 is a diagram showing another example of a conventional refrigeration compressor.

FIG. 4 is a diagram showing an example of a conventional refrigerating and air-conditioning apparatus.

FIG. 5 is a diagram showing an embodiment of a refrigerating and air-conditioning apparatus of the present invention.

FIG. 6 is a diagram showing another embodiment of the refrigerating and air-conditioning apparatus of the present invention.

FIG. 7 is a diagram showing another embodiment of the refrigerating and air-conditioning apparatus of the present invention.

[Explanation of symbols]

 1 ... Suction port 2 ... Discharge port 3 ... Electric motor 4 ... Crank shaft 5 ... Connecting rod 6 ... Piston 7 ... Cylinder 8 ... Main bearing 9 ... Sub bearing 10 ... Discharge pipe 11 ... Accumulator 12 ... Rolling piston 13 ... Shaft 14 ... Fixed Scroll 15 ... Orbiting scroll 16 ... Oil pump 17 ... Refrigeration compressor 18 ... Four-way valve 19 ... Condenser 20 ... Expansion mechanism 21 ... Evaporator 22 ... Moisture adsorption device 23 ... Oil separator

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Keizo Nakajima 1006 Kadoma, Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Inventor Shigehiro Sato, 1006 Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd.

Claims (6)

[Claims] 1. A refrigerating compressor using hydrofluorocarbon as a refrigerant and at least one of ester oil, ether oil and carbonate oil as a refrigerating machine oil, wherein oil applied to parts of the refrigerating compressor or of the refrigerating compressor is used. A refrigeration compressor characterized in that ether oil and / or carbonate oil is used as oil used during assembly. 2. The refrigeration compressor has a rolling bearing,
The refrigerating compressor according to claim 1, wherein the part of the refrigerating compressor is a rolling bearing. 3. The refrigeration compressor has an oil pump,
The refrigeration compressor according to claim 1, wherein the component of the refrigeration compressor is an oil pump. 4. The refrigeration compressor has a built-in electric motor, and a component of the refrigeration compressor is an insulating film electric wire, and the ether oil and the ether oil are used as coating oil for the insulating film electric wire in the step of forming a winding. The refrigerating compressor according to claim 1, wherein a carbonate oil is used. 5. In a refrigerating air-conditioning apparatus using hydrofluorocarbon as a refrigerant and at least one of ester oil, ether oil and carbonate oil as a refrigerating machine oil, oil applied to parts of a refrigerating compressor or an assembly of the refrigerating compressor. A refrigerating and air-conditioning apparatus characterized in that ether oil and / or carbonate oil is used as an oil used at times and a water adsorption device is provided. 6. A refrigerating air-conditioning apparatus using hydrofluorocarbon as a refrigerant and at least one of ester oil, ether oil and carbonate oil as a refrigerating machine oil, oil applied to parts of a refrigerating compressor or an assembly of the refrigerating compressor. A refrigerating and air-conditioning apparatus, characterized in that ether oil and / or carbonate oil is used as an oil used at times, and the refrigerating machine oil contains a moisture trapping additive.