JP2020188640A - Refrigeration cycle device - Google Patents

Abstract

To enhance the reliability of a refrigeration cycle device using an actuation medium including HFO1123.SOLUTION: In a refrigeration cycle device with an actuation medium containing 1,1,2- trifluoroethylene encapsulated therein, a compressor includes an electric motor part 162, a compression mechanism part 163, and a lubricating oil in a sealed container 161, the electric motor part has a stator 167 and a stator winding 170, and coil ends 170a of the stator winding is covered with a resin material. Thus, the actuation medium can be prevented from infiltrating into the coil ends 170a, and disproportion reaction can be prevented from occurring because the actuation medium is not interposed between the coil ends 170a even if the electric motor part 162 abnormally generates heat to cause layer short circuit in the coil ends 170a of the stator winding 170. Consequently, it is possible to improve the reliability of the refrigeration cycle device with the actuation medium containing 1,1,2- trifluoroethylene encapsulated therein.SELECTED DRAWING: Figure 2

Description

The present invention relates to a refrigeration cycle apparatus using a working medium containing HFO1123.

In general, a refrigeration cycle device is formed by connecting a compressor, a four-way valve, a radiator (or condenser), an expansion means such as a capillary tube or an expansion valve, an evaporator, etc., if necessary, to form a refrigeration cycle. A cooling or heating action is performed by circulating a refrigerating cycle working medium (refrigerant or heat medium) inside.

The US ASHRAE34 standard stipulates that fluorocarbons (fluorocarbons are referred to as R ○○ or R ○○○) as working media for refrigerating cycles (hereinafter, simply referred to as working media) in these refrigeration cycle devices. A halogenated hydrocarbon derived from methane or ethane called (hereinafter referred to as R ○○ or R ○○○) is known.

R410A is often used as the operating medium for the refrigeration cycle device as described above, but the global warming potential (GWP) of the R410A refrigerant is as large as 2090, which is problematic from the viewpoint of preventing global warming.

Therefore, from the viewpoint of preventing global warming, for example, HFO1123 (1,1,2-trifluoroethylene) and HFO1132 (1,2-difluoroethylene) have been proposed as small refrigerants for GWP (for example, patents). Document 1 or Patent Document 2).

International Publication No. 2012/157964 International Publication No. 2012/157765

However, the above-mentioned HFO1123 (1,1,2-trifluoroethylene) and HFO1132 (1,2-difluoroethylene) are less stable than conventional refrigerants such as R410A, and are disproportionated when radicals are generated. It may change to another compound due to the conversion reaction.

Since the disproportionation reaction involves a large amount of heat release, it may reduce the reliability of the compressor or refrigeration cycle device. Therefore, when HFO1123 or HFO1132 is used in a compressor or a refrigeration cycle device, it is necessary to suppress this disproportionation reaction.

Such a disproportionation reaction occurs at a high temperature and high pressure in an atmosphere of excessively high temperature and high pressure, particularly in a compressor, and when high energy is applied, this is the starting point.

For example, the discharge pressure (high pressure side of the refrigeration cycle) rises excessively due to conditions that are not normal operating conditions, that is, the blower fan on the condenser side is stopped, the refrigeration cycle circuit is blocked, and the like. As a result, the temperature also rises excessively.

Under such a condition, a lock abnormality of the compressor occurs, and if the power supply to the compressor is continued even under this lock abnormality, the electric power of the compressor is excessively supplied and the electric motor generates abnormal heat. .. As a result, the insulation of the stator windings constituting the stator of the electric motor is melted and broken, causing a phenomenon called layer short between the conductors, which becomes a high energy source and induces a disproportionation reaction.

Then, once the disproportionation reaction occurs, the chain reaction causes a high pressure rise instantaneously and partially (inside the compressor), which may reduce the reliability of the compressor and the refrigeration cycle device. Therefore, it is important to suppress the disproportionation reaction.

The present invention has been made in view of these points, and an object of the present invention is to improve the reliability of a refrigeration cycle apparatus using an operating medium containing HFO1123.

In order to achieve the above object, the present invention uses a working medium containing 1,1,2-trifluoroethylene in a refrigeration cycle circuit configured by connecting a compressor, a condenser, an expansion means, and an evaporator. In the enclosed refrigeration cycle device, the compressor contains an electric motor unit, a compression mechanism unit, and a lubricating oil in a closed container, and the electric motor unit has a stator and a stator winding, and the stator winding has the same. The coil end is covered with a resin material.

With the above configuration, it is possible to prevent the working medium from entering the coil end, and even if the motor part generates abnormal heat and a layer short occurs at the coil end of the stator winding, the working medium is located at the site where the layer short occurs. Since there is no such thing, the high energy source due to the layer short does not come into contact with the working medium, and the occurrence of the disproportionation reaction can be prevented.

With the above configuration, the present invention can provide a highly reliable refrigeration cycle apparatus using an operating medium containing HFO1123.

Schematic configuration of the refrigeration cycle apparatus according to the first embodiment of the present invention. Longitudinal sectional view of the compressor used in the refrigeration cycle apparatus according to the first embodiment. Perspective view of the stator of the compressor of the refrigeration cycle apparatus according to the first embodiment. An enlarged perspective view of a cross section of a main part of a stator of a compressor of a refrigerating cycle apparatus according to the first embodiment. Enlarged sectional view of a main part of the stator in the compressor of the refrigeration cycle apparatus according to the second embodiment of the present invention. Enlarged perspective view of the main part of the stator in the compressor of the refrigeration cycle apparatus according to the third embodiment of the present invention.

The first invention is a refrigeration cycle apparatus in which a working medium containing 1,1,2-trifluoroethylene is sealed in a refrigeration cycle circuit configured by connecting a compressor, a condenser, an expansion means, and an evaporator. The compressor contains an electric motor portion, a compression mechanism portion, and a lubricating oil in a closed container, the electric motor portion has a stator and a stator winding, and the coil end of the stator winding is The structure is covered with a resin material.

As a result, it is possible to prevent the working medium from entering the coil end, and even if the motor part generates abnormal heat and a layer short occurs at the coil end of the stator winding, the working medium will be placed at the site where the layer short occurs. Since it does not exist, the high energy source due to the layer short does not come into contact with the working medium, and the occurrence of the disproportionation reaction can be prevented.

In the second invention, in the first invention, the resin material is a heat-shrinkable film and is configured to cover the coil end.

As a result, it is possible to prevent the working medium from entering the coil end, and even if the motor part generates abnormal heat and a layer short occurs at the coil end of the stator winding, the working medium will be placed at the site where the layer short occurs. Since it does not exist, the high energy source due to the layer short does not come into contact with the working medium, and the occurrence of the disproportionation reaction can be prevented.

Further, the coil end is coated with a heat-shrinkable film, and an inexpensive member can be used to obtain an effect of preventing the occurrence of a disproportionation reaction.

In the third invention, in the first invention, the resin material is a dipping resin, and the resin is dipping processed on the coil end.

It is possible to prevent the working medium from entering the coil end, and even if the motor part generates abnormal heat and a layer short occurs at the coil end of the stator winding, the working medium exists at the site where the layer short occurs. Therefore, the high energy source due to the layer short does not come into contact with the working medium, and the occurrence of the disproportionate reaction can be prevented.

Further, the dipping resin is a coating of a resin obtained by dipping the coil end, and it is possible to prevent the occurrence of a disproportionation reaction while ensuring the performance of the compressor by exerting a heat exhausting action through the coating. That is, it is possible to achieve both ensuring the compressor performance and preventing the occurrence of the disproportionation reaction, and greatly improve the reliability.

In the fourth invention, in the first or third invention, the resin material is a varnish containing a resin as a main component, and the coil end is impregnated with the varnish.

It is possible to prevent the working medium from entering the coil end, and even if the motor part generates abnormal heat and a layer short occurs at the coil end of the stator winding, the working medium exists at the site where the layer short occurs. Therefore, the high energy source due to the layer short does not come into contact with the working medium, and the occurrence of the disproportionate reaction can be prevented.

Further, since the coil end is covered with varnish impregnation, the occurrence of disproportionation reaction can be more reliably prevented by a simple construction method.

A fifth invention is a configuration characterized in that, in the first to fourth inventions, the resin material is an insulating resin.

This enhances the insulation performance of the stator windings covered with the insulating member, enhances the effect of suppressing the occurrence of layer shorts themselves, prevents the occurrence of disproportionation reactions, and greatly improves reliability. Can be done.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The present invention is not limited to this embodiment.

(Embodiment 1)
FIG. 1 is a schematic configuration diagram of the refrigeration cycle device according to the first embodiment of the present invention, and FIG. 2 is a vertical cross-sectional view of the compressor used in the refrigeration cycle device.

The refrigeration cycle device 10 of the present embodiment shows a case where the present invention is applied to an air conditioner, and as shown in FIG. 1, includes an indoor unit 11, an outdoor unit 12, and a pipe 13 connecting them. The indoor unit 11 includes a heat exchanger 14 used as an evaporator or a condenser, and the outdoor unit 12 has a heat exchanger 15, a compressor 16, a decompression device 17, and a controller used as a condenser or an evaporator. It has 18.

The heat exchanger 14 of the indoor unit 11 and the heat exchanger 15 of the outdoor unit 12 are connected in an annular shape by a pipe 13, whereby a refrigeration cycle is formed.

Specifically, the heat exchanger 14 of the indoor unit 11, the compressor 16, the heat exchanger 15 of the outdoor unit 12, and the decompression device 17 are connected in an annular shape by the pipe 13 in this order. Further, a four-way valve 19 for switching heating and cooling is provided in the pipe 13 connecting the heat exchanger 14, the compressor 16, and the heat exchanger 15. The indoor unit 11 includes a blower fan, a temperature sensor, an operation unit and the like (not shown), and the outdoor unit 12 includes a blower, an accumulator and the like (not shown). Further, the pipe 13 is provided with various valve devices (including a four-way valve 19), a strainer, and the like (not shown).

The heat exchanger 14 included in the indoor unit 11 exchanges heat between the indoor air sucked into the indoor unit 11 by the blower fan and the operating medium flowing inside the heat exchanger 14. The indoor unit 11 blows air warmed by heat exchange into the room during heating, and blows air cooled by heat exchange into the room during cooling. The heat exchanger 15 included in the outdoor unit 12 exchanges heat between the outside air sucked into the outdoor unit 12 by the blower and the operating medium flowing inside the heat exchanger 15.

FIG. 2 shows a compressor 16 used in the refrigeration cycle circuit. In the present embodiment, the compressor 16 is composed of a closed rotary compressor, and the electric motor unit 162 is inside the closed container 161. The compression mechanism unit 163 is housed, the inside is filled with a high-temperature and high-pressure working medium and lubricating oil, and the bottom is an oil storage unit 164 for storing lubricating oil.

The electric motor unit 162 is a so-called brushless motor, and includes a rotor 166 fixed to the crankshaft 165 of the compression mechanism unit 163 and a stator 167 provided around the rotor 166.

The rotor 166 is configured by mounting a permanent magnet on the rotor core and integrating it. Further, the stator 167 is configured by dispersing the stator winding 170 around the stator core with an insulating paper. The stator winding 170 may be configured as a centralized winding.

The stator winding 170 is covered with an insulating member, and the insulation thereof is enamel or enamel, for example, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), aramid polymer, polyphenylene sulfide (PPS), and the like. It consists of a heavy coating.

Further, a lead wire 171 is drawn out from the stator winding 170, and the other end of the lead wire 171 is connected to the power supply terminal 172. The power supply terminal 172 includes three terminals, each of which is connected to an inverter type controller 18 (see FIG. 1).

The controller 18 receives a power supply from an external power supply 20 (see FIG. 1) and causes a switching element to pass a current through the stator winding 170 so that a rotating magnetic field is generated in the rotor 166.

The compression mechanism unit 163 has a cylinder 174 forming the compression chamber 173 and a rolling piston 175 arranged in the compression chamber 173 in the cylinder 174. The rolling piston 175 rotates in the compression chamber while abutting against a vane (not shown) due to the rotation of the crankshaft 165, and sucks and compresses the working medium from the suction pipe 179.

The compressed working medium is discharged from the discharge muffler 176 into the container inner space 177 in the closed container 161 and discharged from the discharge pipe 178 to the outside of the compression mechanism unit 163.

The compression mechanism unit 163 has two upper and lower cylinders 174, but the cylinder 174 may have only one stage.

Further, in the compressor 16, an accumulator 180 is provided in the suction pipe 179 in order to prevent liquid compression in the compression chamber 173. The accumulator 180 separates the working medium into gas and liquid, and guides only the refrigerant gas to the suction pipe 179.

Next, the working medium enclosed in the refrigeration cycle circuit will be described.

The working medium enclosed in this refrigeration cycle circuit contains at least 1,1,2-trifluoroethylene (HFO1123) as a refrigerant component. 1,1,2-trifluoroethylene has the structure of the following formula (1), and two hydrogen atoms (H) bonded to the carbon atom (C) at the 1-position of ethylene are fluorine (F). ), And one of the two hydrogen atoms bonded to the carbon atom at the 2-position is replaced with fluorine.

1,1,2-Trifluoroethylene contains a carbon-carbon double bond. Ozone in the atmosphere generates hydroxyl radicals (OH radicals) by a photochemical reaction, and these hydroxyl radicals easily decompose double bonds. Therefore, 1,1,2-trifluoroethylene has little effect on ozone depletion and global temperature.

However, 1,1,2-trifluoroethylene causes a rapid disproportionation reaction when high energy such as layer short is applied under high temperature and high pressure conditions as described above due to this good degradability. In this disproportionation reaction, a self-decomposition reaction in which molecules of 1,1,2-trifluoroethylene are decomposed occurs, and following this self-decomposition reaction, the carbon generated by the decomposition is polymerized to form soot. Reactions and the like occur. When an active radical is generated due to a layer short or the like in a high temperature and high pressure state, the active radical reacts with 1,1,2-trifluoroethylene to cause the above-mentioned disproportionation reaction. Since this disproportionation reaction is accompanied by heat generation, active radicals are generated by this heat generation, and further, the disproportionation reaction is induced by the active radicals. In this way, the generation of active radicals and the generation of the disproportionation reaction are linked, so that the disproportionation reaction proceeds rapidly.

Therefore, in the present invention, as shown in FIG. 3 or 4, the coil end 170a of the stator winding 170, which causes a layer short, which is a source of the disproportionation reaction, is covered with the resin material 181.

Here, FIG. 3 is a perspective view of the stator, and FIG. 4 is an enlarged perspective view of a cross section of a main part of the stator.

In FIG. 3 or 4, the coil end 170a of the stator winding 170 is covered with a heat-shrinkable film 182 so as to wrap the entire winding of the coil end 170a.

Next, the effects of the refrigeration cycle apparatus 10 configured as described above will be described below.

First, the basic operation of the refrigeration cycle device will be briefly explained. In the cooling operation or the dehumidifying operation, the compressor 16 of the outdoor unit 12 compresses and discharges the working medium, and the compressed working medium is sent to the heat exchanger 15 of the outdoor unit 12 via the four-way valve 19. Since the heat exchanger 15 exchanges heat between the outside air and the working medium, the working medium condenses and liquefies. The liquefied working medium is decompressed by the decompression device 17 and sent to the heat exchanger 14 of the indoor unit 11. In the heat exchanger 14, the working medium evaporates due to heat exchange with the indoor air to become a gasified working medium. This working medium returns to the compressor 16 of the outdoor unit 12 via the four-way valve 19. The compressor 16 compresses the working medium and discharges it to the heat exchanger 15 again via the four-way valve 19.

Further, in the heating operation, the compressor 16 of the outdoor unit 12 compresses and discharges the working medium, whereby the working medium is sent to the heat exchanger 14 of the indoor unit 11 via the four-way valve 19. In the heat exchanger 14, the working medium is condensed and liquefied by heat exchange with the indoor air. The liquefied working medium is decompressed by the decompression device 17 to become a gas-liquid two-phase medium, and is sent to the heat exchanger 15 of the outdoor unit 12. Since the heat exchanger 15 exchanges heat between the outside air and the gas-liquid two-phase medium, the gas-liquid two-phase medium evaporates and becomes a gasified working medium, and returns to the compressor 16. The compressor 16 compresses the gasified working medium and discharges it to the heat exchanger 14 of the indoor unit 11 again via the four-way valve 19.

Here, during the above operation, for example, if the blower fan on the condenser side is stopped, the refrigeration cycle circuit is blocked, or the like, the discharge pressure of the working medium (high pressure side of the refrigeration cycle) rises excessively. Along with this, the temperature inside the compressor 16 rises significantly, and finally the insulation of the stator winding 170 is destroyed and a layer short occurs at the coil end 170a.

However, in the embodiment of the present invention, the coil end 170a is covered with the heat-shrinkable film 182, which can prevent the working medium from entering the inside of the heat-shrinkable film 182, whereby the electric motor unit 162 becomes abnormal. Even if a layer short occurs at the coil end 170a of the stator winding 170 due to heat generation, the working medium does not exist at the site where the layer short occurs on the coil end 170a, so a high energy source due to the layer short is generated. It is possible to prevent the occurrence of disproportionation reaction without contacting the working medium. Further, the coil end 170a is coated with the heat-shrinkable film 182, and the effect of preventing the occurrence of the disproportionation reaction can be obtained with an inexpensive member.

(Embodiment 2)
FIG. 5 is a perspective view of a main part of the stator.

As shown in FIG. 5, the embodiment of the present invention is a method of immersing the coil end 170a in a liquid insulating resin for coating, and the coil end 170a is coated with the dipping resin 183. ..

In the embodiment of the present invention, as in the first embodiment, it is possible to prevent the working medium from entering the coil end, the electric motor portion generates abnormal heat, and a layer short occurs at the coil end of the stator winding. However, since the working medium does not exist at the site where the layer short occurs, the high energy source due to the layer short does not come into contact with the working medium, and the occurrence of the disproportionation reaction can be prevented.

In particular, in the present embodiment, the coil end 170a is coated with the dipping resin 183, and the coating has a high heat transfer coefficient. Therefore, the heat exhausting action against the heat generated by the coil is exerted through the coating. It is possible to prevent the occurrence of disproportionation reaction while ensuring the performance of the compressor. That is, it is possible to achieve both ensuring the compressor performance and preventing the occurrence of the disproportionation reaction, and greatly improve the reliability.

The configuration and operation / effect other than the above are the same as those in the first embodiment, and the description thereof will be omitted.

(Embodiment 3)
FIG. 6 is an enlarged perspective view of a cross section of a main part of the stator.

In the embodiment of the present invention, as shown in FIG. 6, an insulating varnish 184 is drip-impregnated on the coil end 170a or applied with a brush or the like as a resin material, and then dried and fixed to cover the coil end 170a. It is a structure that has been made.

In the embodiment of the present invention, as in the first embodiment, it is possible to prevent the working medium from entering the coil end, and even if the electric motor portion generates abnormal heat and a layer short occurs at the coil end of the stator winding. Since the working medium does not exist at the site where the layer short occurs, the high energy source due to the layer short does not come into contact with the working medium, and the occurrence of the disproportionation reaction can be prevented.

In particular, in the present embodiment, the coil end 170a is impregnated with a varnish containing a resin as a main component, and the coil end 170a is coated, so that the occurrence of disproportionation reaction is more reliably prevented by a simple construction method. can do.

The configuration and operation / effect other than the above are the same as those in the first embodiment, and the description thereof will be omitted.

Further, the resin material 181 that coats the coil end is formed of an insulating resin such as a polyimide resin, a phenol resin, an alkyd resin, or an elastomer, thereby enhancing the insulating performance of the stator winding coated with the insulating member. The effect of suppressing the occurrence of the layer short itself is enhanced, the occurrence of the disproportionate reaction can be prevented, and the reliability can be greatly improved.

As described above, the refrigeration cycle apparatus of the present embodiment can prevent the occurrence of a disproportionation reaction.

The present invention has been described by taking the case where the refrigerating cycle device is an air conditioner as an example, but this is a refrigerating cycle in which components such as a compressor, a condenser, an expansion means, and an evaporator are connected by piping. If it is an apparatus, specific application examples are not particularly limited, and for example, refrigerators (for home and business use), dehumidifiers, showcases, ice makers, heat pump type water heaters, heat pump type washer / dryers, vending machines, etc. It may be.

Further, in the present embodiment, the rotary compressor has been described as an example of the compressor, but this is described by using another compression type, for example, a positive displacement compressor such as a scroll type or a reciprocating type, or a centrifugal type compressor. Any compressor such as a machine may be used.

As described above, the present invention can improve the reliability of the refrigeration cycle apparatus using the working medium containing HFO1123. Therefore, it can be widely applied to various applications such as residential and commercial air conditioners, car air conditioners, water heaters, refrigerators / freezers, showcases, and dehumidifiers.

10 Refrigeration cycle device 11 Indoor unit 12 Outdoor unit 13 Piping 14 Heat exchanger 15 Heat exchanger 16 Compressor 17 Decompression device 18 Controller 19 Four-way valve 20 External power supply 161 Sealed container 161a Body shell 162 Electric motor part 163 Compressor mechanism part 164 Oil storage Part 165 Crank shaft 166 Rotor 167 Stator 167a End face 170 Stator winding 170a Coil end 171 Lead wire 172 Power supply terminal 173 Compressor chamber 174 Cylinder 176 Discharge muffler 177 Container space 178 Discharge pipe 179 Suction pipe 18 Accumulator 1 Heat shrink film 183 Dipping resin 184 Insulating varnish

Claims (5)

A refrigeration cycle apparatus in which a working medium containing 1,1,2-trifluoroethylene is sealed in a refrigeration cycle circuit configured by connecting a compressor, a condenser, an expansion means, and an evaporator, and the compression is performed. The machine contains an electric motor part, a compression mechanism part, and a lubricating oil in a closed container, the electric motor part has a stator and a stator winding, and the coil end of the stator winding is covered with a resin material. A refrigeration cycle device characterized by. The refrigeration cycle apparatus according to claim 1, wherein the resin material is a heat-shrinkable film and is configured to cover the coil end. The refrigeration cycle apparatus according to claim 1, wherein the resin material is a dipping resin, and the coil end is subjected to a resin dipping process. The refrigeration cycle apparatus according to any one of claims 1 or 3, wherein the resin material is a varnish containing a resin as a main component, and the coil end is impregnated with the varnish. The refrigeration cycle apparatus according to any one of claims 1 to 4, wherein the resin material is a heat-resistant insulating resin.

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