JPH09196518A - Refrigerating cycle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To secure stability of the performance of a refrigerating cycle over a long period of time in the case where use is made of a refrigerant containing hydrofluorocarbon and a refrigerating machine oil of polyol ester as working mediums by disposing a mechanism for scavenging organic acids and free metallic ions. SOLUTION: A mechanism for scavenging organic acids and free metallic ions is disposed in a refrigerating cycle. To put it in detail, the mechanism has a structure combining a moisture absorbent, a weakly basic ion exchange resin, and a chelating resin, that is, for example, the moisture absorbent 7 in beads, the ion exchange resin 8 in beads, and the chelating resin 9 in beads are stuck in a mesh 10 and placed in a container 11 which permits the passage of working fluid. In a refrigerating cycle having a refrigerating compressor, condenser, expansion mechanism, and evaporator each equipped with such a scavenging mechanism 12 for organic acids and free metallic ions the performance can be stabilized over a lond period of time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigerating cycle including a refrigerating compressor using a refrigerant containing hydrofluorocarbon and a polyol ester refrigerating machine oil as a working medium, a condenser, an expansion mechanism such as an expansion valve, and an evaporator. The present invention relates to a refrigerating cycle in which an organic acid scavenging mechanism that suppresses hydrolysis of a polyol ester and formation of a fatty acid metal salt associated with the hydrolysis is arranged for stable operation over a period of time.

[0002]

2. Description of the Related Art Conventionally, in the field of refrigeration and air conditioning such as refrigerators, air conditioners, and refrigerators, as a refrigerant, CFCs having a fluorine atom and a chlorine atom in its molecular structure, for example, R- which is generally called chlorofluorocarbon (CFC) 11 (trichloromonofluoromethane), R-12 (dichlorodifluoromethane), R-22 (monochlorodifluoromethane) generally called hydrochlorofluorocarbon (HCFC), etc. have been used. However, when released into the atmosphere, these CFC compounds are hardly decomposed in the troposphere, react with ultraviolet light in the stratosphere, and destroy the ozone layer in the decomposition process, thereby destroying the global environment. As a problem, its use is being regulated internationally. For this reason, studies have been widely conducted on alternative fluorocarbon substances having a zero ozone depletion potential, which are generally called hydrofluorocarbons (HFCs) that do not contain chlorine atoms in their molecules.

However, in a refrigeration cycle using HFC as a refrigerant, it is necessary to use a polar refrigerating machine oil such as polyalkylene glycol (PAG) or ester from the viewpoint of compatibility with the HFC refrigerant. And HFC
Since the refrigerant itself has a higher polarity than CFC and HCFC refrigerants, the working fluid itself consisting of the refrigerant and the refrigerating machine oil has a much higher water absorption than the conventional system. Among the refrigerating machine oil having the polarity, ester compounds have been studied as a refrigerating machine oil to be used with an HFC refrigerant because they are superior to PAGs in terms of thermal stability and electrical characteristics, but the ester is As a property of the compound, it causes hydrolysis in the presence of water, and therefore, a polyol ester composed of a hindered alcohol and various fatty acids (organic acids), which hardly hydrolyze, is regarded as promising.

In order to suppress hydrolysis of refrigerating machine oil, an adsorbent desiccant such as zeolite is provided in the refrigerating system in order to remove as much water as possible in the refrigerating system.

Further, for example, in Japanese Patent Laid-Open No. 5-66075, H
For car air conditioners using FC-134a refrigerant, HFC-134a
Disclosed is a method for efficiently removing water by disposing a water removing device in the low-pressure pipe in consideration of the difference in saturated water content between the gas and liquid states. JP-A-4-122792 proposes a refrigeration cycle equipped with an ion exchange resin to adsorb and remove lower fatty acids (organic acids) produced by hydrolysis of the refrigeration oil in order to suppress deterioration of the refrigeration oil. Has been done.

As a refrigerating machine oil, a method of adding various acid moisture scavengers in order to secure the stability of the base oil has been proposed (adding an epoxy-containing fluorine-containing polysiloxane to 100 parts by weight of lubricating oil). JP-A-4-36387, JP-A-4-55498 of PAG-based refrigerating machine oil containing a di- or trivalent polyol glycidyl ether, JP-A-1-93393 of a lubricating oil composition containing an epoxy-containing polysiloxane ,
JP-A-6-1970 of composition for refrigerator working fluid in which glycidyl ether type epoxy compound is added to ester oil,
JP-A-6-240277 discloses a refrigerating machine oil in which glycidyl aromatic mono- or dicarboxylic acid or an epoxycycloalkyl group-containing compound is added to a polyether, and limonene oxide, α-pinene oxide, or L-carbon oxide is used as a base oil. Refrigerating machine oil containing a selected epoxy compound, such as JP-A-6-240279.

[0007]

However, if only a desiccant, for example, a zeolite known as a molecular sieve is placed in the refrigeration system, the amount of adsorbed water will be dominated by the equilibrium adsorbed amount at the ambient temperature in which the desiccant is placed. Therefore, it is impossible to capture all the water in the system, and it is impossible to prevent the hydrolysis of the ester compound.

Further, when an acid moisture scavenger is added to the refrigerating machine oil, by capturing an organic acid produced by hydrolysis, the acid catalyst effect in the hydrolysis reaction of the ester compound by the organic acid is suppressed, and the hydrolysis is performed. Although the reaction can be prevented from being promoted, it often leads to a polymerization reaction of the acid moisture scavenger itself, and as a result, there is a problem that the polymer causes the clogging of the capillary portion such as a capillary.

Further, in a refrigeration cycle equipped with an ion exchange resin, the removal rate greatly varies depending on the dissociation constant of the organic acid metal salt to be removed from the refrigeration cycle and the exchange capacity of the ion exchange resin, and the organic acid metal salt in the capillary portion is changed. However, there is a problem that the blockage due to the precipitation of is not sufficiently prevented.

Further, even when the organic acid is captured by the ion exchange resin, only the metal ion component is left in the refrigeration system, and as a new reaction activator,
There was a problem that it became one of the causes of the deterioration of the refrigerator oil.

The present invention solves the problems of the conventional refrigeration cycle as described above, and uses a refrigerant containing hydrofluorocarbon and a polyol ester refrigerating machine oil that can operate stably for a long period of time as a working medium. An object is to provide a refrigeration cycle including an expansion mechanism such as a condenser and an expansion valve, and an evaporator.

[0012]

In order to solve the above problems, the present invention has the following constitution. (1) In a refrigeration cycle including a refrigeration compressor that uses a refrigerant containing hydrofluorocarbon and a polyol ester refrigeration oil as a working fluid, a condenser, an expansion mechanism, and an evaporator, a mechanism that traps organic acids and free metal ions is arranged. A refrigeration cycle characterized by that. (2) The refrigeration cycle according to (1), wherein the mechanism for capturing the organic acid and the free metal ion is arranged in the flow path between the condenser and the evaporator in the refrigeration cycle. (3) The mechanism for trapping organic acids and free metal ions is arranged inside the accumulator, oil separator, suction strainer or receiver that has less pressure loss with respect to the flow of the working fluid during the refrigeration cycle. The refrigeration cycle described in (1) above. (4) A mechanism for capturing an organic acid and a free metal ion is characterized in that it is composed of a macroporous weak basic ion exchange resin, a chelate resin and a water adsorbent (1),
The refrigeration cycle according to (2) or (3). (5) A mechanism that captures organic acids and free metal ions, which is composed of a macroporous weakly basic ion exchange resin, a chelate resin, and a water adsorbent, has a mechanism in which the working fluid flowing inside the refrigeration cycle main body The refrigeration cycle according to (1) or (2), which has a structure of flowing into a macroporous weakly basic ion exchange resin or chelate resin layer after passing. (6) The refrigeration cycle according to (4) or (5), wherein the macroporous weakly basic ion exchange resin uses a styrene / divinylbenzene copolymer as a base resin. (7) The refrigeration cycle according to (4) or (5), wherein the chelate resin has an iminodiacetic acid group, and the resin matrix is a chelate resin which is a styrene / divinylbenzene copolymer or polyphenol. (8) The refrigeration cycle according to (4) or (5), wherein the water adsorbent is a zeolite composed of synthetic crystalline aluminosilicate. (9) The refrigeration cycle according to (4) or (5), wherein the macroporous weakly basic ion-exchange resin molded product is in the form of beads, fibers, or an aggregate thereof. (10) The shape of the chelate resin molded body is bead-shaped, or is fibrous or an aggregate thereof (4) or
The refrigeration cycle described in (5).

According to the present invention thus constructed, a refrigerating cycle including a refrigerating compressor using a refrigerant containing hydrofluorocarbon and a polyol ester refrigerating machine oil as a working fluid, a condenser, an expansion mechanism such as an expansion valve and an evaporator. If a mechanism for capturing an organic acid or a free metal ion is arranged, it suppresses / reduces an increase in the concentration of an organic acid which is generated along with the hydrolysis of a polyol ester refrigerating machine oil and which is also a factor that accelerates the hydrolysis reaction. It is also possible to remove the metal ion component in the fatty acid metal salt, which is caused by the reaction with these organic acids and which causes the phenomenon of deposition and blockage at the capillaries in the refrigeration system such as expansion valves and capillaries. By doing so, it is possible to obtain a refrigeration cycle that can operate stably for a long period of time.

By arranging a mechanism for trapping the organic acid and the free metal ion, it is necessary to add an acid / water trapping agent which may cause a clogging phenomenon due to its own reaction polymer in the refrigerator oil composition. As a result, the refrigeration cycle that can be stably operated for a long period of time can be obtained.

Further, the mechanism for trapping the organic acid and the free metal ion basically causes a pressure loss when it is arranged in the flow path of the working fluid. Therefore, in order to minimize the pressure loss, a high pressure is required. By placing the working fluid in the liquid state between the condenser and the expansion mechanism, it is possible to minimize the deterioration of the capacity of the refrigeration cycle.

Further, even in the low-pressure liquid phase state in which the working fluid between the expansion mechanism and the evaporator is partially in the vapor phase state, removal of organic acids and free metal ions from the liquid phase and effective water content from the vapor phase part. It can be removed.

Further, if a mechanism for trapping the organic acid and free metal ions is arranged inside the accumulator having a larger flow cross-sectional area than the flow path pipe, the pressure loss is small even if the working fluid is in the gas phase. In addition, it is possible to minimize the deterioration of the refrigeration cycle capacity.

Further, if a mechanism for trapping the organic acid and free metal ions in the refrigerating system such as an oil separator, a suction strainer or a liquid receiver is arranged in a portion where the refrigerating machine oil stays, the organic acid and the free acid in the refrigerating machine oil It is possible to efficiently remove free metal ions.

Further, in the structure in which the mechanism for capturing the organic acid and the free metal ion is composed of a mixed layer or a multi-stage layer of a macroporous type weak basic ion exchange resin, a chelate resin and a water adsorbent, a polyol ester refrigerating machine oil is used. Generated as a result of the reaction between the organic acid produced by the hydrolysis of and the metal components that are present in the refrigeration system such as abrasion powder present in the system that causes clogging in the tube section and metal components that are mixed during piping processing, etc. It becomes possible to adsorb and remove the organic acid metal salt to be adsorbed and removed from the working medium by the ion exchange resin and the chelate resin, or decomposed. Furthermore, by combining with a water adsorbent, it becomes possible to suppress the hydrolysis reaction of the polyol ester refrigerating machine oil, and especially by using zeolite as the water adsorbent, the decomposition of the organic acid metal salt by the interaction with its active surface. Is expected to be promoted. It is effective to use an ion exchange resin, a chelate resin, and a water adsorbent together in a filling amount that does not cause a pressure loss problem.
The ion exchange resin, the chelate resin and the water adsorbent are effective even if they are used separately.

Further, the chelating resin having an iminodiacetic acid group has a good selective adsorption property to copper ions and iron ions, and is effective in adsorbing and removing metal ions produced by decomposition of the organic acid metal salt.

Further, among the macroporous weakly basic ion exchange resins, the styrene / divinylbenzene copolymer has a large exchange capacity and excellent physical strength, and can maintain stable performance in long-term use. .

Furthermore, the use of zeolite as a water adsorbent also has excellent water absorption properties, has a small chemical interaction with a refrigerant containing hydrofluorocarbon and a polyol ester refrigerating machine oil, and can operate stably for a long period of time. Can be obtained.

Furthermore, if the macroporous weakly basic ion exchange resin and chelate resin moldings are in the form of beads, even if the ion exchange resin and chelate resin moldings are filled in the container in which the working medium can flow. While allowing the working medium to flow, it is possible to increase the contact surface area per weight of the ion exchange resin and the chelate resin molded body that contributes to the capture reaction of the organic acid and the free metal ion, and improve the capture efficiency. it can.

Further, if the macroporous weakly basic ion exchange resin and the chelate resin molded body are fibrous or an aggregate thereof, the ion exchange resin and the chelate resin molded body are provided inside the container in which the working medium can flow. It is possible to flow the working medium even if filled, and it is possible to increase the contact surface area per weight of the ion exchange resin and the chelate resin molded body that contributes to the capture reaction of the organic acid and the free metal ion, thereby improving the capture efficiency. Can be improved.

Furthermore, the structure of the mechanism for trapping the organic acid and the free metal ion is such that the ion exchange resin and the chelate resin are sandwiched between the water adsorbent in a bead-like or fibrous form, so that the operating conditions of the refrigeration system can be improved. It is also possible to deal with the case where the flow direction of the working fluid changes due to the switching of the operating fluid, and since zeolite is used as the water adsorbent, the organic acid contained in the working fluid during the contact process with the active surface By contacting the ion exchange resin and the chelate resin in a state in which a part of the metal salt is decomposed and ionized, it becomes possible to improve the substitution effect.

[0026]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1, 2 and 3 are piping diagrams of a refrigeration cycle equipped with a general refrigeration compressor, condenser, expansion mechanism and evaporator. As shown in FIG. 1, the refrigeration cycle is composed of a refrigeration compressor 1, a condenser 2, an expansion mechanism 3, an evaporator 4, and a pipe 5 connecting them. The refrigeration cycle of FIG. 2 has a four-way valve 6, and by switching this, the flow path of the working fluid can be changed and the functions of the condenser and the evaporator can be changed. The refrigeration cycle of FIG. 3 further includes an oil separator 22 for separating refrigerating machine oil mixed with the refrigerant from the refrigerant gas discharged from the compressor, and a receiver for preventing the liquefied refrigerant from staying in the condenser. 23 is a piping diagram of a refrigeration cycle including a suction strainer for removing dust, metal, and the like mixed in the refrigerant.

The refrigeration cycle of the present invention is characterized by further arranging a mechanism for trapping the organic acid and the free metal ion. That is, specifically, it has a structure formed by combining a water absorbent with a weakly basic ion exchange resin and a chelate resin, and the water absorbent includes zeolite, silica gel, activated clay, activated alumina, etc. Is preferred.

Further, the weakly basic ion exchange resin is preferably a macroporous type resin, a styrene / acrylic cross-linking agent copolymer resin, a styrene / divinylbenzene copolymer resin as a base resin, and a tertiary or quaternary amino as an exchange group. A macroporous weak basic ion exchange resin having a styrene / divinylbenzene copolymer as a base resin, which has a large exchange capacity and is excellent in organic contamination and physical strength, is preferable.

The chelate resin is a styrene type,
Examples thereof include those having functional groups such as an iminodiacetic acid group, a polyamine group, a thiol group, and a dithiocarbamic acid group added to an acrylic or phenolic polymer substrate. Particularly, a chelate resin having an iminodiacetic acid group having a weak acid chelate structure. Is preferred.

As a structure of a mechanism for trapping an organic acid and a free metal ion, in which a substance capable of trapping an organic acid and a free metal ion in which a working medium in a refrigeration cycle can flow, is arranged, for example, FIG. Examples shown in FIG. 7 can be given, but the present invention is not limited to these.

In FIG. 4, a bead-shaped water absorbent 7, a bead-shaped ion exchange resin 8 and a bead-shaped chelating resin 9 are sandwiched between meshes 10 to allow a working fluid to flow therethrough.
It is an example of the organic acid and free metal ion trapping mechanism 12 housed in. Here, the ion exchange resin and the chelate resin for capturing the organic acid and the free metal ion and the water absorbent may be separated and stored in separate containers. FIG. 5 shows a structure in which the fixing spring 13 is incorporated in the structure of FIG.

FIG. 6 shows a structure in which a fibrous ion-exchange fiber 8 and a fibrous chelate fiber 9 are sandwiched between filters 14, and a bead-shaped water absorbent 7 is sandwiched between them by a mesh 10. It is an example of the organic acid and free metal ion trapping mechanism 12 housed in a container 11 which can be distributed. As the filter, foam, glass filter, glass wool, steel wool or the like can be used.

FIG. 7 shows an example in which the water absorbent, the ion exchange resin and the chelate resin are separated and used in the refrigeration system. The filter portion 17 is composed of fibrous ion exchange fibers, It has a structure in which a filter portion 16 made of fibrous chelate fiber is arranged inside and outside in a tubular shape, and the check valve 15 causes the working fluid to flow in the same direction as the trapping mechanism described above. It has a structure that can handle changes.

In the organic acid and free metal ion trapping mechanism shown as the embodiment above, flow resistance occurs in the refrigeration cycle because all circulating working medium flows. Therefore, the location of the trapping mechanism should be such that the flow resistance is small and the working medium flows in a liquid phase, that is, the flow path between the condenser and the evaporator is installed. This is preferable because the decrease can be reduced. More specifically, it is desirable to install it in the flow path between the expansion mechanism and the condenser in which the working fluid always flows in the high-pressure liquid state.

FIG. 8 shows the refrigerating compressor 1, the condenser 2, the expansion mechanism 3, the evaporator 4, and the condenser 2 and the evaporator 4 of the present invention.
It is a piping diagram showing the whole refrigerating cycle composition provided with mechanism 12 which captures an organic acid and a free metal ion in the channel between. The configuration of the refrigeration cycle is almost the same as that of a conventionally known one except that the refrigeration cycle is provided with a mechanism for trapping the organic acid and the free metal ion, and thus the detailed description of the refrigeration cycle is omitted.

As other installation locations, a portion having a large flow cross-section or a portion where refrigerating machine oil stays in the refrigeration system, such as an accumulator 20, a suction strainer 21, an oil separator 22, a receiver 12, a refrigerating compressor. It is effective to install a mechanism for trapping an organic acid and free metal ions in the shell of No. 1 without occupying the entire flow cross section. However, since the temperature inside the shell of the refrigeration compressor becomes high, deterioration of the ion exchange resin and the chelate resin used may be accelerated, which is not always preferable.

FIG. 9 shows a structural example of the organic acid and free metal ion trapping mechanism when it is installed at such a position. FIG.
In the above, the bag 18 in which the working medium can flow is filled with the ion exchange resin 8 and the chelate resin 9. Such an organic acid and free metal ion trapping mechanism 19 may be placed in an accumulator, a suction strainer, an oil separator or a liquid receiver. Where bag 1
There is no problem even if 8 is filled with a water absorbent. Alternatively, a float or the like may be attached to the trapping mechanism 19 so that the trapping mechanism 19 may be suspended in the accumulator, suction strainer, oil separator, or liquid receiver.

[0039]

EXAMPLES Hereinafter, more specific examples will be described. (Example 1) IONAC AFP-329 (SYBRON CHEMIC), which is a weakly basic ion exchange resin, with 10 g of DIAION CR11 (manufactured by Mitsubishi Chemical Co., Ltd.), which is a chelating resin, in a copper container.
ALS Co., Ltd.) 5g each was filled on both sides of the same chelating resin through a mesh, and further, an organic acid and a free metal ion trapping mechanism composed of a structure in which 30g of each zeolite was placed on the outside of the chelate resin, were prepared, It was installed between the condenser of the room air conditioner and the capillary. Here, by sandwiching both sides of the zeolite with a mesh, the same structure is maintained in strength.

In addition to the above room air conditioner system and room air conditioner system not equipped with an organic acid and free metal ion trapping mechanism, a polyol ester refrigerating machine oil 250 is used.
g, 700 g of R407C as a refrigerant, and 0.5 g of water were charged, and continuous operation was performed for 2000 hours. When the total acid number of the refrigerating machine oil is measured after the operation is completed, it is 0.03 mg in the room air conditioner system equipped with the organic acid and the free metal ion capturing mechanism.
It was KOH / g, but it was 0.2 mgKOH / g in the room air conditioner system that was not equipped.

When disassembling and analyzing the capillary part, it was observed that fatty acid iron salts were attached to the room air conditioner system that is not equipped with the organic acid and free metal ion trapping mechanism. Nothing was detected in the system. (Example 2) Polystyrene-based chelate fiber in a copper container
10 g of IDA-Na (manufactured by Toray Industries, Inc.) and ion exchange fiber IONEX (Toray Industries, Inc.)
An organic acid and free metal ion trapping mechanism composed of 10 g of glass wool filter (manufactured by Co., Ltd.) sandwiched between glass wool filters and 30 g of zeolite arranged outside the filter was prepared and installed between the condenser and the capillary of the room air conditioner.

Here, the same structure is maintained in strength by sandwiching both sides of the zeolite with a mesh. 250g of polyol ester refrigerating machine oil and R407 as a refrigerant in the above room air conditioner system and room air conditioner system not equipped with organic acid and free metal ion trapping mechanism.
It was filled with 700 g of C and 0.5 g of water and continuously operated for 2000 hours. When the total acid value of the refrigerating machine oil was measured after the operation was completed, it was 0.02 mgKOH / g in the room air conditioner system equipped with the organic acid and free metal ion trapping mechanism, but in the room air conditioner system not equipped. Was 0.2 mg KOH / g. In addition, when disassembling and analyzing the capillary part, it was observed that fatty acid iron salts were attached in the room air conditioner system that was not equipped with the organic acid and free metal ion trapping mechanism, but in the system equipped Nothing was detected. (Example 3) Chelating resin Amberlite (IRC-71) having an iminodiacetic acid group as a functional group in a bag in which a working medium can flow
8) (Rohm and Haas Co.) 10 g and Diaion WA11 (Mitsubishi Chemical Co., Ltd.), which is a weakly basic ion exchange resin, are added, and further 30 g of zeolite is added so that the packing does not flow out from the bag. It was sealed to create an organic acid and free metal ion trapping mechanism.

A float made of a material that is chemically stable to a refrigerant containing a polyol ester refrigerating machine oil and hydrofluorocarbon was attached to the sealed bag, and the float was placed in an accumulator in the refrigeration cycle of the room air conditioner. The above room air conditioner system and room air conditioner system not equipped with organic acid and free metal ion trapping mechanism are filled with 250 g of polyol ester refrigeration oil, 700 g of R407C as a refrigerant, and 0.5 g of water for 2000 hours of continuous operation. went.

When the total acid number of the refrigerating machine oil was measured after the operation was completed, it was 0.03 mgKOH / g in the room air conditioner system equipped with the organic acid and free metal ion trapping mechanism, but the room air conditioner not equipped In this system, it was 0.2 mgKOH / g. In addition, when disassembling and analyzing the capillary part, it was observed that fatty acid iron salts were attached in the room air conditioner system that was not equipped with the organic acid and free metal ion trapping mechanism, but in the system equipped Nothing was detected.

As described above, the refrigerating compressor, the condenser, the expansion mechanism and the evaporator which use the refrigerant containing hydrofluorocarbon having the organic acid and the free metal ion trapping mechanism of the present invention and the polyol ester refrigerating machine oil as the working medium are provided. The provided refrigeration cycle enables stable operation for a long period of time.

[0046]

As is apparent from the above description,
According to the present invention, there is provided a refrigeration cycle including a refrigeration compressor, a condenser, an expansion mechanism, and an evaporator, which uses a refrigerant containing hydrofluorocarbon and a polyol ester refrigerating machine oil as a working medium, which can operate stably for a long period of time. can do.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram showing a refrigeration cycle including a refrigeration compressor, a condenser, an expansion mechanism, and an evaporator.

FIG. 2 is an overall configuration diagram showing a refrigeration cycle including a refrigeration compressor, a condenser, a four-way valve, an evaporator, and an accumulator.

FIG. 3 is an overall configuration diagram showing a refrigeration cycle including a refrigeration compressor, a condenser, a four-way valve, an expansion mechanism, an evaporator, an accumulator, a suction strainer, an oil separator, and a liquid receiver.

FIG. 4 is a diagram showing a structural example of an organic acid and free metal ion trapping mechanism used in the refrigeration cycle of the present invention.

FIG. 5 is a diagram showing another configuration example of the organic acid and free metal ion trapping mechanism used in the refrigeration cycle of the present invention.

FIG. 6 is a diagram showing another configuration example of the organic acid and free metal ion trapping mechanism used in the refrigeration cycle of the present invention.

FIG. 7 is a diagram showing another configuration example of the organic acid and free metal ion trapping mechanism used in the refrigeration cycle of the present invention.

FIG. 8 is an overall configuration diagram of a refrigeration cycle including a refrigeration compressor, a condenser, a four-way valve, an expansion mechanism and an evaporator, and an organic acid and free metal ion trapping mechanism, which is an embodiment of the present invention. .

FIG. 9 is a diagram showing another configuration example of the organic acid and free metal ion trapping mechanism used in the refrigeration cycle of the present invention.

[Explanation of symbols]

 1 Refrigerating Compressor 2 Condenser 3 Expansion Mechanism 4 Evaporator 5 Piping 6 Four-way Valve 7 Moisture Adsorbent 8 Weakly Basic Ion Exchange Resin 9 Chelate Resin 10 Mesh 11 Container for Flowing Working Medium 12 Organic Acid and Free Metal Ion Capture Mechanism 13 Spring 14 Filter 15 Check valve 16 Filter made of weakly basic ion exchange resin 17 Filter made of chelate resin 18 Bags 19 Organic acid and free metal ion trapping mechanism 20 Accumulator 21 Suction strainer 22 Oil separator 23 Liquid receiver

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Keizo Nakajima 1006 Kadoma, Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Inventor, Shigehiro Sato, 1006 Kadoma, Kadoma, Osaka (72) Inventor Yusuke Ozaki 1006 Kadoma, Kadoma-shi, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Nobuo Sonoda 1006 Kadoma, Kadoma City Osaka Prefecture Matsushita Electric Industrial Co., Ltd. Matsushita Refrigerator Co., Ltd. 4-2-5 Takaidahondori, Higashi-Osaka, Osaka Prefecture (72) Inventor Masanori Hirota 4-5-2-5 Takaidamoto-dori, East Osaka, Osaka Prefecture

Claims (10)

[Claims] 1. A refrigeration cycle including a refrigerating compressor using a refrigerant containing hydrofluorocarbon and a polyol ester refrigerating machine oil as a working fluid, a condenser, an expansion mechanism, and an evaporator has a mechanism for trapping an organic acid and a free metal ion. A refrigeration cycle characterized by being arranged. 2. The refrigeration cycle according to claim 1, wherein a mechanism for trapping an organic acid and free metal ions is arranged in a flow path between the condenser and the evaporator during the refrigeration cycle. . 3. A mechanism for trapping an organic acid and a free metal ion is arranged in an accumulator, an oil separator, a suction strainer or a receiver which has a small pressure loss with respect to the flow of the working fluid during the refrigeration cycle. The refrigeration cycle according to claim 1, wherein 4. The mechanism for trapping an organic acid and a free metal ion is composed of a macroporous weakly basic ion exchange resin, a chelate resin and a water adsorbent. Refrigeration cycle described in. 5. A mechanism composed of a macroporous weak basic ion exchange resin, a chelate resin and a water adsorbent for trapping an organic acid and a free metal ion has a working fluid flowing in the refrigeration cycle body adsorbing water. The refrigeration cycle according to claim 1 or 2, wherein the refrigeration cycle has a structure in which the macroporous type weakly basic ion-exchange resin and the chelate resin layer flow after passing through the agent. 6. The refrigeration cycle according to claim 4, wherein the macroporous weakly basic ion exchange resin uses a styrene / divinylbenzene copolymer as a base resin. 7. The refrigerating cycle according to claim 4, wherein the chelate resin has an iminodiacetic acid group and the resin matrix is a chelate resin which is a styrene / divinylbenzene copolymer or polyphenol. 8. The water adsorbent is a zeolite composed of synthetic crystalline aluminosilicate.
Or the refrigeration cycle according to 5. 9. The refrigeration cycle according to claim 4, wherein the shape of the macroporous weakly basic ion-exchange resin molding is a bead shape, a fibrous shape or an aggregate thereof. 10. The chelate resin molding has a bead shape.
Alternatively, the refrigerating cycle according to claim 4 or 5, wherein the refrigerating cycle is fibrous or an aggregate thereof.