Compressor

Abstract

To provide a compressor capable of suppressing discharge in a conductor portion of a magnet coil by using a working medium containing an ethylene-based fluoroolefin and capable of suppressing occurrence of disproportionation reaction in the working medium.SOLUTION: A compressor of the present disclosure uses a working medium containing an ethylene-based fluoroolefin and circulates the working medium in a refrigerant circuit by driving an electric motor to perform air conditioning, in which a conductive layer is formed on the outside of an insulating coating of an electric line constituting a magnet coil of the electric motor.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present disclosure relates to a compressor. [Background technology]

[0002] Patent Document 1 discloses an enameled wire having an insulating coating composed of at least two insulating layers around a conductor, with the outermost insulating layer being composed of a polyamideimide coating, and with a mixed resin insulating layer composed of a mixed resin coating of polyimide resin and polyamideimide resin provided on the inner layer side of the outermost insulating layer. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2005-302597 A Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure provides a compressor that uses a working medium containing an ethylene-based fluoroolefin, and that can suppress discharge in the conductor parts of the magnet coil and suppress the occurrence of a disproportionation reaction in the working medium. [Means for solving the problem]

[0005] The compressor in the present disclosure uses a working medium containing an ethylene-based fluoroolefin to drive an electric motor and circulate the working medium in a refrigerant circuit to perform air conditioning, and a conductive layer is formed on the outside of the insulating coating of an electric wire that constitutes a magnet coil of the electric motor. Effect of the Invention

[0006] According to the compressor of the present disclosure, since the conductive layer is formed on the outside of the insulating coating, the conductive layers of the electric wires come into contact with each other, thereby reducing the potential difference in the vicinity of the contact portion, and suppressing the occurrence of discharge in the vicinity of the contact portion, thereby suppressing the occurrence of disproportionation reaction of the working medium. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a schematic diagram showing an overall configuration of a refrigeration cycle device according to a first embodiment. [Diagram 2] FIG. 1 is a schematic diagram showing a compressor according to a first embodiment. [Diagram 3] FIG. 1 is a schematic diagram showing the wires of a magnet coil according to the first embodiment; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] (The knowledge and other information that formed the basis of this disclosure) At the time the inventors came up with the idea of ​​the present disclosure, in a compressor driven by a drive motor for an air conditioner, an enamel insulating layer was provided on the conductor of the magnet coil of the drive motor, and electricity was applied and the compressor was operated with the magnet coil in contact with refrigerant vapor. However, when using a working medium containing an ethylene-based fluoroolefin, if the compressor is operated with the insulating coating of the magnet coil degraded and a certain amount of energy or more is discharged in the conductor part of the magnet coil, a self-decomposition reaction of the working medium may occur, which may cause a sudden increase in the pressure of the working medium. Furthermore, in compressors, it is common to use an inverter to drive a highly efficient embedded permanent magnet motor and vary the rotation speed of the compressor. However, the inventors discovered a problem in that inverter drive causes a surge voltage to be applied between the conductors of the magnet coil, which can cause partial discharge and accelerate deterioration of the insulating coating. In order to solve this problem, the inventors have come to form the subject of the present disclosure. Therefore, the present disclosure provides a compressor that uses a working medium containing an ethylene-based fluoroolefin, and that can suppress discharge in the conductor parts of the magnet coil and suppress the occurrence of disproportionation reactions in the working medium.

[0009] Hereinafter, the embodiments will be described in detail with reference to the drawings. However, more detailed description than necessary may be omitted. For example, detailed description of already well-known matters or duplicate description of substantially the same configuration may be omitted. It should be noted that the accompanying drawings and the following description are provided to enable those skilled in the art to fully understand the present disclosure, and are not intended to limit the subject matter described in the claims.

[0010] (Embodiment 1) [1-1. Configuration] [1-1-1. Overall configuration of the refrigeration cycle device] FIG. 1 is a schematic diagram showing the overall configuration of a refrigeration cycle device 1 to which a compressor of the present disclosure is applied. As shown in FIG. 1, the refrigeration cycle apparatus 1 includes an outdoor unit 10 and an indoor unit 20. The outdoor unit 10 and the indoor unit 20 are connected via a refrigerant pipe 11 to form a refrigerant circuit through which the refrigerant circulates. The refrigeration cycle device 1 uses a working fluid containing an ethylene-based fluoroolefin in the refrigeration cycle circuit. Many ethylene-based fluoroolefins have a low GWP. On the other hand, it is known that ethylene-based fluoroolefins can cause a disproportionation reaction when exposed to a discharge phenomenon under high temperature and high pressure. The occurrence of a disproportionation reaction can cause a sudden pressure rise in the refrigeration cycle circuit. Details of the working fluid will be described later.

[0011] The outdoor unit 10 includes a compressor 12, an outdoor heat exchanger 13, and an outdoor expansion valve 14. The compressor 12 is, for example, a scroll compressor, which draws in a gaseous working medium, compresses it, and discharges it. The outdoor heat exchanger 13 is, for example, a fin-tube type heat exchanger, and drives an outdoor fan (not shown) to cause the working medium flowing inside to exchange heat with the outside air. The outdoor expansion valve 14 is a valve whose opening degree can be changed, and reduces the pressure of the working medium passing therethrough.

[0012] The indoor unit 20 includes an indoor heat exchanger 21 and an indoor expansion valve 22 . The indoor heat exchanger 21 is, for example, a fin-tube type heat exchanger, and exchanges heat between the working medium flowing inside and the indoor air by driving an indoor fan (not shown). The indoor expansion valve 22 is a valve whose opening and closing and its opening degree can be changed.

[0013] [1-1-2. Compressor configuration] FIG. 2 is a schematic diagram showing the compressor according to the first embodiment. As shown in FIG. 2, the compressor 12 is an internal intermediate pressure type multi-stage compression rotary compressor, and a drive motor 31 is accommodated in the upper part inside a cylindrical casing 30 made of steel plate. The drive motor 31 includes a stator 32 attached in an annular shape along the inner circumferential surface of the upper space of the casing 30, and a mover 33 inserted with a gap inside the stator 32. A rotating shaft 34 extending in the axial direction of the casing 30 is attached to the center of the mover 33. The stator 32 includes a laminate 35 formed by laminating annular electromagnetic steel sheets, and a magnet coil 36 wound around the laminate 35. The mover 33 includes a laminate formed by laminating electromagnetic steel sheets, and a permanent magnet disposed within the laminate (not shown).

[0014] FIG. 3 is a schematic diagram showing the electric wire 40 of the magnet coil 36 in the first embodiment. 3, the electric wire 40 constituting the magnet coil 36 is composed of a conductor 41 made of copper or the like, and an insulating coating 42 that covers the outside of the conductor 41. The insulating coating 42 is formed of a resin such as polyester. In the present embodiment, a conductive layer 43 is formed on the outside of the insulating coating 42. The conductive layer 43 is formed by, for example, a conductive resin, a resin mixed with a conductive filler, or metal deposition.

[0015] The conductive layer can be formed, for example, by applying and curing an epoxy resin in which 10 to 30 wt% of carbon black is dispersed as a conductive filler. The substrate is not limited to epoxy resin, and polyester, polyesterimide, polyamideimide, polyimide, etc. can also be used. Examples of the conductive filler include carbon-based materials such as carbon black, carbon nanofiber, carbon nanotube, and graphene. Examples of the metal-based materials include silver, copper, and nickel. Examples of the metal oxide-based materials include indium oxide, zinc oxide, and tin oxide. Examples of the conductive polymer-based materials include polyaniline, polythiophene, and polypyrrole. Furthermore, a conductive polymer may be mixed into the base material.

[0016] The conductive layer 43 may be formed over the entire magnet coil 36 after the electric wire 40 having the insulating coating 42 formed thereon is wound around the magnet coil 36, or the electric wire 40 having the conductive layer 43 formed on the outside of the insulating coating 42 in advance may be wound.

[0017] Further, a low-pressure side compression mechanism 50 and a high-pressure side compression mechanism 51 driven by a drive motor 31 are housed in the lower interior of the casing 30 . The low-pressure side compression mechanism 50 is provided with a low-pressure side suction port 52 and a low-pressure side discharge port 53, and is configured to compress low-pressure refrigerant to an intermediate pressure. Further, the high-pressure side compression mechanism 51 is provided with a high-pressure side suction port 54 and a high-pressure side discharge port 55, and is configured to compress the intermediate-pressure refrigerant to a high pressure. The inside of the casing 30 is maintained at the intermediate pressure.

[0018] A low-pressure side discharge port 53 of the compressor 12 is connected to a high-pressure side suction port 54 of the compressor 12 via an intermediate pipe 56. A high-pressure side discharge port 55 of the compressor 12 is connected to the outdoor heat exchanger 13 via the refrigerant pipe 11.

[0019] [1-1-3. Working medium] The working medium used in the air conditioner 1 is a working medium containing a fluoroolefin (fluoroalkene) such as an ethylene-based fluoroolefin. The specific type of fluoroolefin is not particularly limited, and may include, for example, fluoroethylenes such as 1,1,2-trifluoroethylene (HFO1123), trans-1,2-difluoroethylene (HFO1132(E)), cis-1,2-difluoroethylene (HFO1132(Z)), 1,1-difluoroethylene (HFO1132a), tetrafluoroethylene (FO1114, TFE), and monofluoroethylene (HFO1141); 1,2,3,3,3-pentafluoropropene (HFO-1225ye), 2,3,3,3-tetrafluoropropene (HFO-1234yf), 1,3,3,3-tetrafluoropropene (HFO-1234ze), 1,2,3,3-tetrafluoropropene (HFO-1234ye), and 3,3,3-trifluoropropene (HFO-1243zf).

[0020] The working medium may contain two or more refrigerant components. That is, it may contain a fluoroolefin selected from the above examples (e.g., 1,1,2-trifluoroethylene) and a second refrigerant component. The second refrigerant component may be, but is not limited to, a hydrofluorocarbon (HFC), a hydrofluoroolefin (HFO), a saturated hydrocarbon, carbon dioxide, or other refrigerant.

[0021] Examples of the hydrofluorocarbon include fluoromethanes such as difluoromethane (R32) and trifluoromethane (R23), fluoroethane (R161), 1,1-difluoroethane (R152a), 1,1,1-trifluoroethane (R143a), 1,1,2,2-tetrafluoroethane (R134), 1,1,1,2-tetrafluoroethane (R134a), pentafluoroethane (R125), fluoroethanes such as difluoroethane and trifluoroethane, and 1,1,1,3,3-pentafluoropropane ( fluoropropanes such as 1,1,1,2,3,3-hexafluoropropane (R236ea), 1,1,1,3,3,3-hexafluoropropane (R236fa), and 1,1,1,2,3,3,3-heptafluoropropane (R227ea); fluorobutanes such as 1,1,1,3,3-pentafluorobutane (R365mfc); and fluoropentanes such as 1,1,1,2,3,4,4,5,5,5-decafluoropentane (R4310mee) and heptafluorocyclopentane (Rc447ef).

[0022] Examples of saturated hydrocarbons include ethane, n-propane, cyclopropane, n-butane, cyclobutane, isobutane (2-methylpropane), methylcyclopropane, n-pentane, isopentane (2-methylbutane), neopentane (2,2-dimethylpropane), and methylcyclobutane, but may be other hydrocarbons. The second refrigerant component may include a plurality of components. That is, the second refrigerant component may include two or more refrigerant components selected from hydrofluorocarbons, hydrofluoroolefins, saturated hydrocarbons, carbon dioxide, and other refrigerants.

[0023] The working medium described above may be a refrigerant classified as mildly flammable (A2L), flammable (A2), or highly flammable (A3) according to ISO817.

[0024] [1-1-4. Disproportionation inhibitor] The working medium used as a refrigerant in the air conditioner 1 may contain a disproportionation inhibitor in addition to the refrigerant components. The disproportionation inhibitor is, for example, a saturated hydrocarbon. The working medium may contain a disproportionation inhibitor consisting of one or more components. Saturated hydrocarbons used as disproportionation inhibitors include ethane, n-propane, cyclopropane, n-butane, cyclobutane, isobutane (2-methylpropane), methylcyclopropane, n-pentane, isopentane (2-methylbutane), neopentane (2,2-dimethylpropane), and methylcyclobutane, but may also be other saturated hydrocarbons. A particularly preferred disproportionation inhibitor is n-propane.

[0025] The disproportionation inhibitor may be, for example, a haloalkane having any one to four carbon atoms. The haloalkane used as the disproportionation inhibitor may have any of 1 to 4 carbon atoms, excluding cases where all of the halogen atoms are fluorine. More specifically, examples of the haloalkane include halomethane (halogenated methane) having one carbon atom, haloethane (halogenated ethane) having two carbon atoms, halopropane (halogenated propane) having three carbon atoms, and halobutane (halogenated butane) having four carbon atoms.

[0026] Specifically, the disproportionation-inhibiting haloalkane may be one having the structure of formula (1) shown below. CpHqXr (1)

[0027] In the formula (1), X is a halogen atom selected from the group consisting of fluorine (F), chlorine (Cl), bromine (Br), and iodine (I). p is an integer of either 1 or 2. q is an integer of 0 or greater. r is an integer of 1 or greater. The sum of q and r is 2p+2. When r is 2 or greater, X is the same or different halogen atom.

[0028] However, the disproportionation-inhibited haloalkanes shown in formula (1) above do not include those in which X is composed only of F. This is because disproportionation-inhibited haloalkanes in which X is composed only of F are compounds that can be used in combination with other refrigerant components and do not substantially function as disproportionation inhibitors.

[0029] In the disproportionation-inhibited haloalkane represented by formula (1), the halogen atom X may be at least one of F, Cl, Br, and I, as described above, but is preferably at least I. When the number of carbon atoms is 2 (p=2) and the number of halogen atoms is 2 or more (r≧2), the halogen atom X is preferably at least F and I.

[0030] The disproportionation-inhibiting haloalkane shown in formula (1) is not particularly limited, and specific examples thereof include (mono)iodomethane (CH3I), diiodomethane (CH2I2), dibromomethane (CH2Br2), bromomethane (CH3Br), dichloromethane (CH2Cl2), chloroiodomethane (CH2ClI), dibromochloromethane (CHBr2Cl), tetraiodomethane (CI4), carbon tetrabromide (CBr4), bromotrichloromethane (CBrCl3), dibromodichloromethane (CBr2Cl2), tribromofluoromethane (CBr3F), fluorodiiodomethane (CHFI), and the like. ), difluorodiiodomethane (CF2I2), dibromodifluoromethane (CBr2F2), trifluoroiodomethane (CF3I), and other halomethanes; 1,1,1-trifluoro-2-iodoethane (CF3CH2I), monoiodoethane (CH3CH2I), monobromoethane (CH3CH2Br), 1,1,1-triiodoethane (CH3CI3), 1-bromo-2-iodotetrafluoroethane (CF2BrCF2I), and other halomethanes.

[0031] The working fluid may contain a plurality of disproportionation inhibitors selected from the above-mentioned saturated hydrocarbons and the above-mentioned haloalkanes. The working fluid may contain one type of saturated hydrocarbon, or may be a working fluid containing two or more types of saturated hydrocarbons. The working fluid may contain one type of haloalkane, or may be a working fluid containing two or more types of haloalkanes.

[0032] A preferred example of the working medium is a mixture containing 1,1,2-trifluoroethylene and n-propane. This working medium may contain the second refrigerant component described above, or may contain other components.

[0033] Each of the above working fluids may contain inevitable impurities, such as various additives including stabilizers added for the purpose of stabilization during transportation or storage, residues or by-products of the raw materials for synthesizing the refrigerant components, and substances mixed in for other reasons.

[0034] The mass ratio of 1,1,2-trifluoroethylene and n-propane contained in the working fluid can be appropriately changed. Thus, in the mixed refrigerant, there are no particular limitations on the content (content) of the fluoroolefin or other refrigerants, or the content (content) of the disproportionation inhibitor. For example, when the total amount of the mixed refrigerant is taken as 100% by mass, the fluoroolefin content may be 50% by mass or more, 60% by mass or more, 70% by mass or more, or 80% by mass or more. Furthermore, when the total amount of the mixed refrigerant is taken as 100% by mass, the propane content may be less than 50% by mass, and may be 40% by mass or less, 30% by mass or less, or 20% by mass or less.

[0035] [1-2. Operation] Next, the operation of the first embodiment will be described. In this embodiment, the compressor 12 is driven to compress the working medium and discharge it toward the outdoor heat exchanger 13 . The high-temperature, high-pressure working medium compressed by the compressor 12 exchanges heat with outside air in the outdoor heat exchanger 13 and is condensed, and then expanded by the outdoor expansion valve 14 . The working medium is then sent to the indoor expansion valve 22, where it is further expanded and sent to the indoor heat exchanger 21. The working medium exchanges heat with the indoor air by the indoor heat exchanger 21 to cool the indoor air, and then is returned to the compressor 12. Through this series of operations, the room can be cooled.

[0036] Here, in the magnet coil 36 of the drive motor 31 of the compressor, as shown in FIG. 3, an electric field is concentrated in an area A near the contact portion between adjacent electric wires 40 because the relative dielectric constant of the working medium is smaller than that of the insulating coating 42. Therefore, discharge may occur in the area A near the contact portion between the adjacent electric wires 40. In the case of a working fluid containing an ethylene-based fluoroolefin, discharging may cause a disproportionation reaction. However, in the present embodiment, since a conductive layer 43 is formed on the outside of the insulating coating 42, when the conductive layers 43 of the electric wires 40 come into contact with each other, the potential difference in the area A near the contact portion can be reduced, and the occurrence of discharge in the area A near the contact portion can be suppressed.

[0037] [1-3. Effects, etc.] As described above, the compressor 1 in this embodiment is a compressor that uses a working medium containing an ethylene-based fluoroolefin and performs air conditioning by driving an electric motor to circulate the working medium in a refrigerant circuit, and a conductive layer 43 is formed on the outside of the insulating coating 42 of the electric wire 40 that constitutes the magnet coil 36 of the electric motor. As a result, since the conductive layer 43 is formed on the outside of the insulating coating 42, the conductive layers 43 of the electric wires 40 come into contact with each other, thereby reducing the potential difference in the contact vicinity region A and suppressing the occurrence of discharge in the contact vicinity region A. As a result, the occurrence of the disproportionation reaction of the working medium can be suppressed.

[0038] In the compressor 1 of the present embodiment, the conductive layer 43 is formed in advance on the outside of the insulating coating 42 of the electric wire 40 before the magnet coil 36 is formed. As a result, even if the conductive layer 43 is formed in advance on the outside of the insulating coating 42 of the electric wire 40, the potential difference in the contact vicinity region A can be reduced, and the occurrence of discharge in the contact vicinity region A can be suppressed. Therefore, the occurrence of the disproportionation reaction of the working medium can be suppressed.

[0039] (Embodiment 2) Next, a second embodiment of the present disclosure will be described. In this embodiment, when forming the conductive layer 43, first, the magnet coil 36 is installed using the electric wire 40 having only the insulating coating 42, and in this state, performance tests as the magnet coil 36, such as a dielectric strength test and an impulse response test, are performed on the magnet coil 36. Then, based on the results of the performance test, the conductive layer 43 is formed on the magnet coil 36 . By forming the conductive layer 43 on the magnet coil 36 based on the performance test in this manner, the conductive layer 43 is formed only on magnet coils 36 that are good products and that satisfy the performance test, thereby eliminating waste in the manufacturing process.

[0040] Here, in the magnet coil 36, the coil ends (the parts protruding above and below the stator 32) are prone to deterioration of the insulating coating 42 for reasons such as the conductor wires 41 being bent when the coil is formed, causing the insulating coating 42 to deform, adjacent conductor wires 41 rubbing against each other due to vibration caused by current flow, and the exposed parts being exposed outside the slots of the stator 32 and therefore potentially coming into contact with foreign objects. However, by forming a conductive layer 43 also on the coil end, in addition to preventing deterioration due to partial discharge, the insulating coating 42 is further covered and displacement relative to the adjacent conductor 41 is restricted, thereby making it possible to suppress deterioration of the insulating coating 42.

[0041] As a means for forming the conductive layer 43, for example, the stator 32 and the conductor 41 having the insulating coating 42 are brought into contact with a liquid conductive resin or a conductive filler mixed resin, and the resin is allowed to permeate and fill the spaces between the conductors 41, and then solidified to form the conductive layer 43. In addition, as a means for forming the conductive layer 43 on the coil end of the magnet coil 36, the conductive layer 43 is formed by applying a liquid conductive resin or a conductive filler mixed resin to the coil end of the magnet coil 36 and drying it. By forming the conductive layer 43 in this manner, the conductive layer 43 can be easily formed.

[0042] As described above, in the compressor 1 of this embodiment, the magnet coil 36 is installed using the electric wire 40 having only the insulating coating 42, and after a performance test of the magnet coil 36 is performed, a conductive layer 43 is formed on the magnet coil 36. This allows the conductive layer 43 to be formed according to the performance of the magnet coil 36.

[0043] (Other embodiments) As described above, the first and second embodiments have been described as examples of the technology disclosed in this application. However, the technology in this disclosure is not limited to these, and can be applied to embodiments in which modifications, substitutions, additions, omissions, etc. are made. In addition, it is also possible to combine the components described in the first and second embodiments to create new embodiments.

[0044] [Configuration supported by the above embodiment] The above embodiment supports the following configurations.

[0045] (Additional Note) (Technology 1) A compressor for performing air conditioning by using a working medium containing an ethylene-based fluoroolefin and driving an electric motor to circulate the working medium in a refrigerant circuit, in which a conductive layer is formed on the outside of the insulating coating of an electric wire that constitutes a magnet coil of the electric motor. According to this configuration, since the conductive layer is formed on the outside of the insulating coating, the conductive layers of the electric wires come into contact with each other, thereby reducing the potential difference in the area near the contact portion, and suppressing the occurrence of discharge in the area near the contact portion, thereby suppressing the occurrence of disproportionation reaction of the working fluid.

[0046] (Technology 2) The compressor according to Technology 1, in which a conductive layer is formed in advance on the outside of the insulating coating of the electric wire before the magnet coil is formed. According to this configuration, even if a conductive layer is formed in advance on the outer side of the insulating coating of the electric wire, the potential difference in the region near the contact portion can be reduced, and the occurrence of discharge in the region near the contact portion can be suppressed, thereby suppressing the occurrence of disproportionation reaction of the working fluid. [Industrial Applicability]

[0047] INDUSTRIAL APPLICABILITY The present disclosure is preferably applicable to a compressor that uses a working medium containing an ethylene-based fluoroolefin, is capable of suppressing discharge in the conductor portion of a magnet coil, and is capable of suppressing the occurrence of a disproportionation reaction in the working medium. [Explanation of symbols]

[0048] 1 Refrigeration cycle equipment 10 Outdoor unit 11 Refrigerant piping 12 Compressor 13 Outdoor heat exchanger 14 Outdoor expansion valve 20 Indoor unit 21 Indoor heat exchanger 22 Indoor expansion valve 30 Casing 31 Drive motor 32 Stator 33 Mover 34 Rotational Axis 35 Laminate 36 Magnet coil 40 Electric wire 41 Conductor 42 Insulation coating 43 Conductive Layer 50 Low pressure side compression mechanism 51 High pressure side compression mechanism 52 Low pressure side intake port 53 Low pressure side outlet 54 High pressure intake port 55 High pressure side outlet 56 Intermediate piping

Claims

1. 1. A compressor for air conditioning using a working medium containing an ethylene-based fluoroolefin and circulating the working medium in a refrigerant circuit by driving an electric motor, comprising: A conductive layer is formed on the outside of the insulating coating of the electric wire that constitutes the magnet coil of the electric motor. Compressor.

2. Before forming the magnet coil, a conductive layer is formed on the outside of the insulating coating of the electric wire. The compressor according to claim 1 .

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