WO2015136981A1

WO2015136981A1 - Compressor and refrigeration cycle system

Info

Publication number: WO2015136981A1
Application number: PCT/JP2015/051129
Authority: WO
Inventors: 英明前山; 訓明松永; 外山　悟; 岳春景山
Original assignee: 三菱電機株式会社; 旭硝子株式会社
Priority date: 2014-03-14
Filing date: 2015-01-16
Publication date: 2015-09-17
Also published as: CN106103992B; JPWO2015136981A1; CN106103992A; JP6293262B2

Abstract

　A compressor (12) is provided with a sealed container (20), a compression element (30), and an electric element (40). The compression element (30) is housed within the sealed container (20). The compression element (30) compresses a refrigerant containing ethylene-based fluorohydrocarbons. The electric element (40) is also housed within the sealed container (20). The electric element (40) drives the compression element (30). Refrigerator oil (25) for lubricating sliding parts of the compression element (30) is stored in the bottom of the sealed container (20). The refrigerator oil (25) contains a flame retardant for suppressing chemical reactions of the refrigerant.

Description

Compressor and refrigeration cycle apparatus

The present invention relates to a compressor and a refrigeration cycle apparatus. The present invention relates to a compressor using, for example, an ethylene-based fluorinated hydrocarbon or a mixture containing an ethylene-based fluorinated hydrocarbon as a refrigerant.

In the field of air conditioners for vehicles, 2,3,3,3-tetrafluoropropene (R1234yf), which is a propylene-based fluorinated hydrocarbon, is a low GWP (global warming potential) refrigerant. In general, propylene-based fluorinated hydrocarbons are characterized by being easily decomposed and polymerized due to the presence of double bonds in the composition.

In the compressor, the surface of the sliding part that becomes high temperature tends to cause decomposition and polymerization of the propylene-based fluorohydrocarbon. Conventionally, there is a method of suppressing the decomposition and polymerization of the refrigerant by configuring the surface portion of the sliding portion with a non-metallic component (see, for example, Patent Document 1).

Tetrafluoroethylene is useful as a monomer for producing fluororesins and fluorine-containing elastomers having excellent heat resistance and chemical resistance, but is a substance that is extremely easily polymerized. Conventionally, in order to suppress the polymerization, there is a method of adding a polymerization inhibitor to tetrafluoroethylene from the time of purification (see, for example, Patent Document 2).

JP 2009-299649 A Japanese Patent Laid-Open No. 11-246447

Conventionally, R410A used as a refrigerant in a stationary air conditioner has a standard boiling point of −51 ° C. In contrast, R1234yf, which is a propylene-based fluorinated hydrocarbon, has a high normal boiling point of -29 ° C. Therefore, the R1234yf refrigerant has a lower operating pressure and a lower refrigeration capacity per suction volume than the R410A refrigerant. When the R1234yf refrigerant is used in a stationary air conditioner, the volume flow rate of the refrigerant must be increased in order to obtain a refrigerating capacity equivalent to that of the R410A refrigerant. Therefore, problems such as an increase in the displacement of the compressor, an increase in pressure loss, and a decrease in efficiency occur.

Therefore, when applying a low GWP refrigerant to a stationary air conditioner, a refrigerant having a low standard boiling point is appropriate. Generally, a refrigerant having a small number of carbons tends to have a low boiling point. For example, it is easier to obtain a refrigerant having a low boiling point than using an ethylene fluorocarbon having 2 carbon atoms than a propylene fluorocarbon having 3 carbon atoms.

However, ethylene-based fluorinated hydrocarbons are more reactive than propylene-based fluorinated hydrocarbons, are thermally and chemically unstable, and are susceptible to decomposition and polymerization. It is difficult to suppress decomposition and polymerization only by the method disclosed in Patent Document 1.

When ethylene-based fluorohydrocarbon is used as a refrigerant, decomposition and polymerization are likely to occur immediately after the generation of the refrigerant. Even when the refrigerant is stored, decomposition and polymerization occur. In order to suppress decomposition and polymerization, even if a polymerization inhibitor as shown in Patent Document 2 is added to the refrigerant from the time of generation, the decomposition and polymerization cannot be sufficiently suppressed. That is, in the compressor, the refrigerant is likely to be decomposed and polymerized at the sliding portion of the compression element and the winding portion of the electric element that become high temperature. The refrigerant circulates in the refrigerant circuit while repeating the phase change from liquid to gas and from gas to liquid, and is vaporized at the sliding portion of the compression element and the winding portion of the electric element. The polymerization inhibitor added to the refrigerant is carried out of the compressor by the vaporized refrigerant. For this reason, the polymerization inhibitor does not reach the sliding portion of the compression element and the winding portion of the electric element, and cannot sufficiently exhibit the effect of preventing decomposition and polymerization.

Some ethylene-based fluorohydrocarbons cause an explosive decomposition reaction triggered by heat generated by the polymerization reaction. Therefore, when ethylene-based fluorohydrocarbon is used as the refrigerant, if the decomposition and polymerization of the refrigerant cannot be sufficiently suppressed, the refrigerant circuit or the compressor may be damaged due to the explosion.

For example, there is 1,1,2-trifluoroethylene (R1123) as one of ethylene fluorocarbons. R1123 has a problem that explosion occurs when ignition energy is applied in a high temperature and high pressure state (see, for example, Non-Patent Document 1). As for this problem, it became clear that explosion occurred due to the chain of disproportionation reaction. Since the disproportionation reaction is caused by the generation of ignition energy (high temperature part), when R1123 is applied to a refrigeration cycle apparatus such as an air conditioner, the sliding part of the compression element that becomes high temperature or the winding of the electric element. Explosion due to disproportionation reaction tends to occur at the line part.

An object of the present invention is to prevent explosion due to a chemical reaction of a refrigerant in a compressor using a refrigerant containing, for example, an ethylene-based fluorohydrocarbon.

A compressor according to an aspect of the present invention includes:
A compression element for compressing a refrigerant containing an ethylene-based fluorohydrocarbon;
An electric element for driving the compression element;
A container for storing refrigerating machine oil for storing the compression element and the electric element and lubricating a sliding portion of the compression element;
A flame retardant is contained in at least one of the sliding portion of the compression element, the winding portion of the electric element, and the refrigerating machine oil.

In the present invention, a compressor using a refrigerant containing an ethylene-based fluorohydrocarbon contains a flame retardant in at least one of the sliding portion of the compression element, the winding portion of the electric element, and the refrigerator oil. Therefore, it is possible to prevent an explosion due to a chemical reaction of the refrigerant at the sliding portion of the compression element or the winding portion of the electric element that becomes high temperature.

The circuit diagram of the refrigerating-cycle apparatus (at the time of cooling) which concerns on embodiment of this invention. The circuit diagram of the refrigerating-cycle apparatus (at the time of heating) which concerns on embodiment of this invention. The longitudinal cross-sectional view of the compressor which concerns on embodiment of this invention. AA sectional view of FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

Embodiment 1 FIG.
1 and 2 are circuit diagrams of a refrigeration cycle apparatus 10 according to the present embodiment. FIG. 1 shows the refrigerant circuit 11a during cooling. FIG. 2 shows the refrigerant circuit 11b during heating.

In the present embodiment, the refrigeration cycle apparatus 10 is an air conditioner. Note that this embodiment can be applied even if the refrigeration cycle apparatus 10 is a device other than an air conditioner (for example, a heat pump cycle apparatus).

1 and 2, the refrigeration cycle apparatus 10 includes

refrigerant circuits

11a and 11b through which refrigerant circulates.

A compressor 12, a four-way valve 13, an outdoor heat exchanger 14, an expansion valve 15, and an indoor heat exchanger 16 are connected to the

refrigerant circuits

11a and 11b. The compressor 12 compresses the refrigerant. The four-way valve 13 switches the direction of refrigerant flow between cooling and heating. The outdoor heat exchanger 14 is an example of a first heat exchanger. The outdoor heat exchanger 14 operates as a condenser during cooling, and dissipates the refrigerant compressed by the compressor 12. The outdoor heat exchanger 14 operates as an evaporator during heating, and heats the refrigerant by exchanging heat between the outdoor air and the refrigerant expanded by the expansion valve 15. The expansion valve 15 is an example of an expansion mechanism. The expansion valve 15 expands the refrigerant radiated by the condenser. The indoor heat exchanger 16 is an example of a second heat exchanger. The indoor heat exchanger 16 operates as a condenser during heating, and dissipates the refrigerant compressed by the compressor 12. The indoor heat exchanger 16 operates as an evaporator during cooling, and heats the refrigerant by exchanging heat between the indoor air and the refrigerant expanded by the expansion valve 15.

The refrigeration cycle apparatus 10 further includes a control device 17.

The control device 17 is, for example, a microcomputer. Although only the connection between the control device 17 and the compressor 12 is shown in the figure, the control device 17 is connected not only to the compressor 12 but also to each element connected to the

refrigerant circuits

11a and 11b. The control device 17 monitors and controls the state of each element.

In the present embodiment, a refrigerant containing ethylene-based fluorohydrocarbon is used as the refrigerant circulating in the

refrigerant circuits

11a and 11b. This refrigerant may be a single type of ethylene-based fluorohydrocarbon alone, a mixture of two or more types of ethylene-based fluorohydrocarbons, or one type or two or more types of ethylene-based fluorocarbons. It may be a mixture containing activated hydrocarbons. In other words, if the refrigerant used in the refrigeration cycle apparatus 10 contains 1 to 100% of ethylene-based fluorohydrocarbon, this embodiment can be applied and the effects described later can be obtained.

As a suitable refrigerant, a mixture of 1,1,2-trifluoroethylene (R1123) and difluoromethane (R32) can be used. For example, a mixture containing 40 wt% R1123 and 60 wt% R32 can be used. Either one or both of R1123 and R32 in this mixture may be replaced with another substance. R1123 may be replaced with another ethylene-based fluorohydrocarbon or a mixture of R1123 and another ethylene-based fluorohydrocarbon. Other ethylene-based fluorohydrocarbons include, for example, fluoroethylene (R1141), 1,1-difluoroethylene (R1132a), trans-1,2-difluoroethylene (R1132 (E)), cis-1,2- Difluoroethylene (R1132 (Z)) can be used. R32 is, for example, 2,3,3,3-tetrafluoropropene (R1234yf), trans-1,3,3,3-tetrafluoropropene (R1234ze (E)), cis-1,3,3,3- Tetrafluoropropene (R1234ze (Z)), 1,1,1,2-tetrafluoroethane (R134a), 1,1,1,2,2-pentafluoroethane (R125) may be substituted. . Alternatively, R32 may be replaced with a mixture of any two or more of R32, R1234yf, R1234ze (E), R1234ze (Z), R134a, and R125, for example.

As the refrigerant, R1123 alone (that is, a refrigerant containing 100 wt% R1123) may be used. Similarly to the above mixture, R1123 may be replaced with another ethylene-based fluorohydrocarbon or a mixture of R1123 and another ethylene-based fluorohydrocarbon.

FIG. 3 is a longitudinal sectional view of the compressor 12. 4 is a cross-sectional view taken along the line AA in FIG. In FIG. 3, hatching representing a cross section is omitted.

In the present embodiment, the compressor 12 is a one-cylinder rotary compressor. Note that the present embodiment can be applied even when the compressor 12 is a multi-cylinder rotary compressor or a scroll compressor.

3, the compressor 12 includes a sealed container 20, a compression element 30, an electric element 40, and a crankshaft 50.

The sealed container 20 is an example of a container. A suction pipe 21 for sucking the refrigerant and a discharge pipe 22 for discharging the refrigerant are attached to the sealed container 20.

The compression element 30 is stored in the sealed container 20. Specifically, the compression element 30 is installed in the lower part inside the sealed container 20. The compression element 30 compresses the refrigerant sucked into the suction pipe 21.

The electric element 40 is also accommodated in the sealed container 20. Specifically, the electric element 40 is installed at a position in the sealed container 20 where the refrigerant compressed by the compression element 30 passes before being discharged from the discharge pipe 22. That is, the electric element 40 is installed above the compression element 30 inside the sealed container 20. The electric element 40 drives the compression element 30. The electric element 40 is a concentrated winding motor. The present embodiment can be applied even if the electric element 40 is a distributed winding motor.

Refrigerator oil 25 for lubricating the sliding portion of the compression element 30 is stored at the bottom of the sealed container 20. As the refrigerating machine oil 25, for example, POE (polyol ester), PVE (polyvinyl ether), and AB (alkylbenzene) which are synthetic oils are used. The refrigerating machine oil 25 is selected to have a viscosity that can sufficiently lubricate the compressor 12 even if the refrigerant is dissolved in the oil and that does not reduce the efficiency of the compressor 12. For example, the kinematic viscosity of the base oil at 40 ° C. is about 5 to 300 cSt. As will be described later, the refrigerating machine oil 25 contains a flame retardant.

Hereinafter, details of the compression element 30 will be described.

The compression element 30 includes a cylinder 31, a rolling piston 32, a vane 36, a main bearing 33, and a sub bearing 34.

The outer periphery of the cylinder 31 is substantially circular in plan view. A cylinder chamber 62 that is a substantially circular space in plan view is formed inside the cylinder 31. The cylinder 31 is open at both axial ends.

The cylinder 31 is provided with a vane groove 61 that communicates with the cylinder chamber 62 and extends in the radial direction. A back pressure chamber 63, which is a substantially circular space in plan view, communicated with the vane groove 61 is formed outside the vane groove 61.

The cylinder 31 is provided with a suction port (not shown) through which gas refrigerant is sucked from the

refrigerant circuits

11a and 11b. The suction port passes through the cylinder chamber 62 from the outer peripheral surface of the cylinder 31.

The cylinder 31 is provided with a discharge port (not shown) through which the compressed refrigerant is discharged from the cylinder chamber 62. The discharge port is formed by cutting out the upper end surface of the cylinder 31.

The rolling piston 32 has a ring shape. The rolling piston 32 moves eccentrically in the cylinder chamber 62. The rolling piston 32 is slidably fitted to the eccentric shaft portion 51 of the crankshaft 50.

The shape of the vane 36 is a flat, substantially rectangular parallelepiped. The vane 36 is installed in the vane groove 61 of the cylinder 31. The vane 36 is always pressed against the rolling piston 32 by a vane spring 37 provided in the back pressure chamber 63. Since the inside of the sealed container 20 is at a high pressure, when the operation of the compressor 12 is started, the pressure in the sealed container 20 and the pressure in the cylinder chamber 62 on the back surface of the vane 36 (that is, the surface on the back pressure chamber 63 side). Force due to the difference acts. For this reason, the vane spring 37 is mainly used for the purpose of pressing the vane 36 against the rolling piston 32 when the compressor 12 is started (when there is no difference in the pressure in the sealed container 20 and the cylinder chamber 62).

The main bearing 33 has a substantially inverted T shape when viewed from the side. The main bearing 33 is slidably fitted to a main shaft portion 52 that is a portion above the eccentric shaft portion 51 of the crankshaft 50. The main bearing 33 closes the cylinder chamber 62 and the vane groove 61 of the cylinder 31.

The auxiliary bearing 34 is substantially T-shaped when viewed from the side. The auxiliary bearing 34 is slidably fitted to the auxiliary shaft portion 53 that is a portion below the eccentric shaft portion 51 of the crankshaft 50. The auxiliary bearing 34 closes the cylinder chamber 62 and the lower side of the vane groove 61 of the cylinder 31.

The main bearing 33 includes a discharge valve (not shown). A discharge muffler 35 is attached to the outside of the main bearing 33. The high-temperature and high-pressure gas refrigerant discharged through the discharge valve once enters the discharge muffler 35 and is then discharged from the discharge muffler 35 into the space in the sealed container 20. Note that the discharge valve and the discharge muffler 35 may be provided in the auxiliary bearing 34 or in both the main bearing 33 and the auxiliary bearing 34.

The material of the cylinder 31, the main bearing 33, and the auxiliary bearing 34 is gray cast iron, sintered steel, carbon steel, or the like. The material of the rolling piston 32 is, for example, alloy steel containing chromium or the like. The material of the vane 36 is, for example, high speed tool steel.

A suction muffler 23 is provided beside the sealed container 20. The suction muffler 23 sucks low-pressure gas refrigerant from the

refrigerant circuits

11a and 11b. The suction muffler 23 prevents the liquid refrigerant from directly entering the cylinder chamber 62 of the cylinder 31 when the liquid refrigerant returns. The suction muffler 23 is connected to the suction port of the cylinder 31 via the suction pipe 21. The main body of the suction muffler 23 is fixed to the side surface of the sealed container 20 by welding or the like.

Hereinafter, details of the electric element 40 will be described.

In the present embodiment, the electric element 40 is a brushless DC (Direct Current) motor. The present embodiment can be applied even if the electric element 40 is a motor (for example, an induction motor) other than the brushless DC motor.

The electric element 40 includes a stator 41 and a rotor 42.

The stator 41 is fixed in contact with the inner peripheral surface of the sealed container 20. The rotor 42 is installed inside the stator 41 with a gap of about 0.3 to 1 mm.

The stator 41 includes a stator core 43 and a winding portion 44. The stator core 43 is manufactured by punching a plurality of electromagnetic steel sheets having a thickness of 0.1 to 1.5 mm into a predetermined shape, laminating them in the axial direction, and fixing them by caulking or welding. The winding portion 44 is configured by winding a three-phase winding (that is, a conductor wire) in a concentrated manner on a plurality of teeth (not shown) formed on the stator core 43 via an insulating member 47. The The winding is composed of a core wire and at least one layer of a coating covering the core wire. The material of the core wire is, for example, copper. The material of the film is, for example, AI (amidoimide) / EI (ester imide). The material of the insulating member 47 is, for example, PET (polyethylene terephthalate), PBT (polybutylene terephthalate), FEP (tetrafluoroethylene / hexafluoropropylene copolymer), PFA (tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer). PTFE (polytetrafluoroethylene), LCP (liquid crystal polymer), PPS (polyphenylene sulfide), and phenol resin. A lead wire 45 is connected to the winding portion 44.

A plurality of notches are formed on the outer periphery of the stator core 43 at substantially equal intervals in the circumferential direction. Each notch becomes one of the passages of the gas refrigerant discharged from the discharge muffler 35 to the space in the sealed container 20. Each notch also serves as a passage for the refrigerating machine oil 25 that returns from the top of the electric element 40 to the bottom of the sealed container 20.

The rotor 42 includes a rotor core 46 and a permanent magnet (not shown). As with the stator core 43, the rotor core 46 is formed by punching a plurality of electromagnetic steel sheets having a thickness of 0.1 to 1.5 mm into a predetermined shape, stacking them in the axial direction, and fixing them by caulking or welding. Produced. The permanent magnet is inserted into a plurality of insertion holes formed in the rotor core 46. For example, a ferrite magnet or a rare earth magnet is used as the permanent magnet.

In order to prevent the permanent magnet from coming off in the axial direction, an upper end plate 48 and a lower end plate 49 are respectively provided at the upper end and the lower end of the rotor 42 (that is, both axial ends). The upper end plate 48 and the lower end plate 49 also serve as a rotation balancer. The upper end plate 48 and the lower end plate 49 are fixed to the rotor core 46 by a plurality of fixing rivets (not shown).

The rotor core 46 is formed with a plurality of through holes penetrating substantially in the axial direction. Each through hole becomes one of the passages of the gas refrigerant discharged from the discharge muffler 35 to the space in the sealed container 20, similarly to the cutout of the stator core 43.

When the electric element 40 is configured as an induction motor (not shown), a plurality of slots formed in the rotor core 46 are filled or inserted with a conductor formed of aluminum, copper, or the like. Then, a squirrel-cage winding in which both ends of the conductor are short-circuited by end rings is formed.

A terminal 24 (for example, a glass terminal) connected to an external power source is attached to the top of the sealed container 20. The terminal 24 is fixed to the sealed container 20 by welding, for example. A lead wire 45 from the electric element 40 is connected to the terminal 24.

At the top of the sealed container 20, a discharge pipe 22 having both axial ends opened is attached. The gas refrigerant discharged from the compression element 30 is discharged from the space in the sealed container 20 through the discharge pipe 22 to the external

refrigerant circuits

11a and 11b.

Hereinafter, the operation of the compressor 12 will be described.

Electric power is supplied from the terminal 24 to the stator 41 of the electric element 40 via the lead wire 45. Thereby, the rotor 42 of the electric element 40 rotates. As the rotor 42 rotates, the crankshaft 50 fixed to the rotor 42 rotates. As the crankshaft 50 rotates, the rolling piston 32 of the compression element 30 rotates eccentrically in the cylinder chamber 62 of the cylinder 31 of the compression element 30. The space between the cylinder 31 and the rolling piston 32 is divided into two by the vane 36 of the compression element 30. As the crankshaft 50 rotates, the volumes of these two spaces change. In one space, the refrigerant is sucked from the suction muffler 23 by gradually increasing the volume. In the other space, the volume of the gas refrigerant is gradually reduced to compress the gas refrigerant therein. The compressed gas refrigerant is discharged once from the discharge muffler 35 to the space in the sealed container 20. The discharged gas refrigerant passes through the electric element 40 and is discharged out of the sealed container 20 from the discharge pipe 22 at the top of the sealed container 20.

During the operation of the compressor 12, the gas refrigerant passing through the electric element 40 is not only a plurality of through holes formed in the rotor core 46 and a plurality of notches formed in the stator core 43, but also the stator core 43. , It goes through a gap including a slot formed between adjacent teeth. The refrigerant passing through the slot passes near the winding portion 44.

During operation of the compressor 12, one of the two parts constituting the sliding portion of the compression element 30 slides on the other. The compression element 30 has a plurality of sliding portions as described below.
(1) First sliding part: outer peripheral part 71 of rolling piston 32 and tip 81 of vane 36
(2) Second sliding portion: vane groove 61 of cylinder 31 and side surface portion 82 of vane 36
(3) Third sliding part: inner peripheral part 72 of rolling piston 32 and eccentric shaft part 51 of crankshaft 50
(4) Fourth sliding portion: inner peripheral portion of main bearing 33 and main shaft portion 52 of crankshaft 50
(5) Fifth sliding part: the inner peripheral part of the auxiliary bearing 34 and the auxiliary shaft part 53 of the crankshaft 50

Thus, in the compression element 30, the sliding portion is constituted by a combination of two of the cylinder 31, the rolling piston 32, the vane 36, the main bearing 33, the auxiliary bearing 34, and the crankshaft 50.

When the compressor 12 is configured as a swing type rotary compressor (not shown), the vane 36 is provided integrally with the rolling piston 32, and when the crankshaft 50 is driven, the rolling piston It moves in and out along the receiving groove of the support body rotatably attached to 32. The vane 36 moves in the radial direction while swinging according to the rotation of the rolling piston 32, thereby dividing the inside of the cylinder chamber 62 into a compression chamber and a suction chamber. In this case, the side surface portion 82 of the vane 36 and the receiving groove of the support form a sliding portion.

The support is composed of two columnar members having a semicircular cross section. The support body is rotatably fitted in a circular holding hole formed in an intermediate portion between the suction port and the discharge port of the cylinder 31. Therefore, the outer peripheral part of the support and the inner peripheral part of the holding hole of the cylinder 31 form another sliding part.

As described above, in the present embodiment, a refrigerant containing ethylene-based fluorinated hydrocarbon is used. This refrigerant is thermally and chemically unstable. Therefore, decomposition and polymerization due to a chemical reaction are likely to occur. In particular, the chemical reaction of the refrigerant is accelerated and the decomposition is likely to occur at a portion where the temperature is high.

The sliding portion of the compression element 30 and the winding portion 44 of the electric element 40 are portions that become high temperature when the compressor 12 is operating. The sliding part of the compression element 30 generates heat when the parts slide. The winding portion 44 of the electric element 40 generates heat when a current for rotating the rotor 42 flows through the winding.

Ethylene-based fluorohydrocarbons are highly reactive and cause decomposition and polymerization even when stored at room temperature. In the compressor 12, the decomposition of the refrigerant proceeds due to the sliding of the metals, and the decomposition products are easily polymerized. Even if a polymerization inhibitor is added to the ethylene-based fluorohydrocarbon, the refrigerant vaporizes into the gas at the sliding portion of the compression element 30 and the winding portion 44 of the electric element 40 that have become high in temperature. The polymerization inhibitor is carried away with the refrigerant. Therefore, the polymerization inhibitor does not remain in the sliding portion of the compression element 30 and the winding portion 44 of the electric element 40, and a sufficient effect cannot be exhibited. As a result, the heat generated by the polymerization of the refrigerant may cause an explosive decomposition reaction, which may damage the

refrigerant circuits

11a and 11b or the compressor 12.

In the present embodiment, the refrigerating machine oil 25 contains a flame retardant in order to suppress the chemical reaction of the refrigerant.

In the present embodiment, as the flame retardant contained in the refrigerator oil 25, for example, a halogen flame retardant, a phosphorus flame retardant, or a combination thereof is used.

Generally, flame retardants are used to make organic materials such as plastic, rubber, wood, and fiber difficult to burn.

For example, when a halogen flame retardant decomposes at a high temperature, a halogen atom is generated. The halogen atom extracts a hydrogen atom from a hydrocarbon or the like to generate a hydrogen halide. The hydrogen halide reacts with the active radicals in the combustion gas to inactivate it. At the same time, the halogen atom is regenerated, and the regenerated halogen atom further deactivates the active radical. As described above, the halogen-based flame retardant effectively suppresses the combustion reaction by the catalytic mechanism that is key to the generation of halogen atoms.

Phosphorus flame retardants also exhibit the same effects as halogen flame retardants when radical species generated by decomposition in combustion gas inactivate active radicals.

In the present embodiment, ethylene-based fluorocarbon used as a refrigerant starts an explosive decomposition reaction due to active radicals generated by heat generation or the like. For example, R1123 may cause a disproportionation reaction of CF ₂ = CHF (g) → 1 / 2CF ₄ (g) + 2 / 3C (amorphous) + HF + 44.7 kcal / mol triggered by stimulation such as fever. The disproportionation reaction proceeds explosively as active radicals generated by exothermic reactions react with R1123 molecules and the generation of active radicals is linked. Therefore, if the refrigerating machine oil 25 contains a flame retardant, hydrogen halide that inactivates active radicals is generated from the flame retardant at high temperatures, and an explosive decomposition reaction can be effectively suppressed.

That is, in the present embodiment, a refrigeration for lubricating a sliding portion of the compression element 30 that becomes a high temperature in a compressor is generally used as a flame retardant that is used to make the organic material flame retardant. Mixed with machine oil 25. Thereby, in the compressor 12 using the refrigerant containing the ethylene-based fluorohydrocarbon, explosion due to the chemical reaction of the refrigerant at the sliding portion of the compression element 30 can be prevented. Moreover, since the refrigeration oil 25 also reaches the winding portion 44 of the electric element 40, explosion due to a chemical reaction of the refrigerant in the winding portion 44 of the electric element 40 can be prevented.

Tetrabromobisphenol A (TBBA) can be used as a flame retardant. For example, the refrigerating machine oil 25 preferably contains 0.1% to 5% TBBA. When the refrigerating machine oil 25 containing TBBA is used, even when an active radical that triggers the decomposition reaction of the refrigerant is generated due to heat generation or the like, the active radical is effectively inactivated and the decomposition reaction is effectively suppressed. it can. Therefore, the reliability of the compressor 12 can be sufficiently maintained even when a refrigerant that easily generates a decomposition reaction is used in the compressor 12.

Flame retardants are not limited to TBBA, but include TBBA carbonate oligomer, TBBA epoxy oligomer, decabromodiphenyl ether, hexabromocyclododecane, bis (pentabromophenyl) ethane, bis (tetrabromophthalimide) ethane, brominated polystyrene, dechlorane, chlorende Other types of halogenated flame retardants such as acid and chlorendic anhydride may be used. Alternatively, triphenyl phosphate, tricresyl phosphate, trixylenyl phosphate, 1,3-phenylene bis (diphenyl phosphate), 1,3-phenylene bis (dixylenyl phosphate), bisphenol A bis (diphenyl phosphate), tris ( Phosphorus flame retardants such as dichloropropyl) phosphate, tris (β-chloropropyl) phosphate, 2,2-bis (chloromethyl) trimethylenebis (bis (2-chloroethyl) phosphate) and red phosphorus may be used. Absent.

In the present embodiment, an antimony compound may be added to the flame retardant contained in the refrigerator oil 25.

The effect of the halogen flame retardant can be enhanced by adding an antimony compound to the halogen flame retardant. Although the antimony compound alone has almost no flame retardant effect, it reacts stepwise with a halogen-based flame retardant to produce halogenated antimony, and this acts as a radical trap to exert the flame retardant effect. Therefore, if an antimony compound is added to the flame retardant contained in the refrigerator oil 25, the decomposition reaction of the refrigerant can be more effectively suppressed.

As the antimony compound, for example, antimony trioxide and antimony pentoxide can be used.

Embodiment 2. FIG.
In the present embodiment, differences from the first embodiment will be mainly described.

The configuration of the refrigeration cycle apparatus 10 according to the present embodiment is the same as that of the first embodiment shown in FIGS. The configuration of the compressor 12 is the same as that of the first embodiment shown in FIGS. 3 and 4.

In the first embodiment, the refrigerating machine oil 25 contains a flame retardant for suppressing the chemical reaction of the refrigerant. In the present embodiment, a similar flame retardant is contained in the sliding portion of the compression element 30. Has been. In the present embodiment, the refrigerating machine oil 25 may not contain a flame retardant.

In the present embodiment, at least one part among the parts constituting the sliding portion of the compression element 30 is made of a porous body. The pores of this porous body contain the same flame retardant as in the first embodiment.

For example, the cylinder 31, the main bearing 33, and the auxiliary bearing 34 can be formed as sintered parts that are porous bodies. These sintered parts are preliminarily impregnated with a flame retardant or a refrigerating machine oil 25 containing a flame retardant, and then the compressor 12 is assembled. Thereby, in the sliding part of the compression element 30 which becomes high temperature easily at the time of operation | movement of the compressor 12, a flame retardant oozes out from sintered components and can suppress the decomposition reaction of a refrigerant | coolant.

In the present embodiment, even if the refrigerating machine oil 25 is not sufficiently distributed to the sliding portion of the compression element 30, the sliding portion itself contains a flame retardant, so that the decomposition reaction of the refrigerant is effectively suppressed. be able to.

Also in the present embodiment, an antimony compound may be added to the flame retardant contained in the sliding portion of the compression element 30 as in the first embodiment.

By adding an antimony compound to the sintered part, the effect of the halogen-based flame retardant can be enhanced. Therefore, if an antimony compound is added to the flame retardant contained in the sliding portion of the compression element 30, the decomposition reaction of the refrigerant can be more effectively suppressed.

Also in the present embodiment, a flame retardant may be contained in the sliding portion of the compression element 30 as in the second embodiment.

Embodiment 3 FIG.
In the present embodiment, differences from the first embodiment will be mainly described.

In the first embodiment, the refrigerating machine oil 25 contains a flame retardant for suppressing the chemical reaction of the refrigerant. However, in the present embodiment, the chemical reaction of the refrigerant is applied to the winding portion 44 of the electric element 40. Contains a flame retardant to suppress. In the present embodiment, the refrigerating machine oil 25 may not contain a flame retardant.

In the present embodiment, the same flame retardant as in the first embodiment is contained in the gap between the windings (that is, the conductor wires) constituting the winding portion 44 of the electric element 40.

For example, when a winding having a circular cross section is used in the winding portion 44 of the electric element 40, a gap is generated between adjacent windings. This gap can contain a flame retardant or refrigerating machine oil 25 containing a flame retardant, similar to the pores formed in the sintered part in the second embodiment. For example, a flame retardant is mixed in advance with the processing oil used in the winding process, or the winding is wound around each tooth of the stator core 43 after the winding is preliminarily immersed in the flame retardant. . Thereby, in the winding part 44 of the electric element 40 which is likely to become high temperature due to Joule heat during the operation of the compressor 12, the decomposition reaction of the refrigerant can be suppressed by the flame retardant in the gap between the windings.

In the present embodiment, even if the refrigerating machine oil 25 is not sufficiently spread to the winding portion 44 of the electric element 40, the winding portion 44 itself contains a flame retardant, so that the decomposition reaction of the refrigerant is effectively performed. Can be suppressed.

Also in the present embodiment, as in the first embodiment, an antimony compound may be added to the flame retardant contained in the winding portion 44 of the electric element 40.

By including an antimony compound in the winding portion 44, the effect of the halogen flame retardant can be enhanced. Therefore, if an antimony compound is added to the flame retardant contained in the winding portion 44, the decomposition reaction of the refrigerant can be more effectively suppressed.

Embodiment 4 FIG.
In the present embodiment, differences from the first embodiment will be mainly described.

Usually, the refrigerator oil 25 contains an antiwear agent. The antiwear agent decomposes itself to prevent wear of the sliding portion of the compression element 30. However, the decomposition product of the antiwear agent may react with the decomposition product of the refrigerant containing the ethylene-based fluorocarbon which is easily decomposed to generate a solid. This solid matter accumulates in a narrow flow path such as the expansion valve 15 of the refrigeration cycle apparatus 10 (the same applies when a capillary tube is used in place of the expansion valve 15), which may cause clogging and cause poor cooling. There is.

In the present embodiment, the refrigerator oil 25 does not contain an antiwear agent. For this reason, a solid substance is not produced | generated by reaction with the decomposition product of a wear inhibitor and the decomposition product of the refrigerant | coolant containing ethylene-type fluorocarbon. Therefore, the

refrigerant circuit

11a, 11b is not clogged, and the refrigeration cycle apparatus 10 that can maintain good performance over a long period can be provided.

As mentioned above, although embodiment of this invention was described, you may implement combining some of these embodiment. Alternatively, any one or some of these embodiments may be partially implemented. For example, only one of those described as “parts” in the description of these embodiments may be employed, or some arbitrary combinations may be employed. In addition, this invention is not limited to these embodiment, A various change is possible as needed.

10 refrigeration cycle apparatus, 11a, 11b refrigerant circuit, 12 compressor, 13 four-way valve, 14 outdoor heat exchanger, 15 expansion valve, 16 indoor heat exchanger, 17 control device, 20 sealed container, 21 suction pipe, 22 discharge pipe , 23 Suction muffler, 24 terminal, 25 refrigeration oil, 30 compression element, 31 cylinder, 32 rolling piston, 33 main bearing, 34 secondary bearing, 35 discharge muffler, 36 vane, 37 vane spring, 40 electric element, 41 stator, 42 rotor, 43 stator core, 44 winding part, 45 lead wire, 46 rotor core, 47 insulation member, 48 upper end plate, 49 upper end plate, 50 crankshaft, 51 eccentric shaft part, 52 main shaft part, 53 sub Shaft, 61 vane groove, 62 cylinder chamber, 63 back pressure chamber, 71 outer periphery, 72 Periphery, 81 tip 82 side portion.

Claims

A compression element for compressing a refrigerant containing an ethylene-based fluorohydrocarbon;
An electric element for driving the compression element;
A container for storing refrigerating machine oil for storing the compression element and the electric element and lubricating a sliding portion of the compression element;
A compressor comprising a flame retardant in at least one of the sliding portion of the compression element, the winding portion of the electric element, and the refrigerating machine oil.
The sliding portion of the compression element is composed of two parts in which one part slides on the other part and at least one part is made of a porous body, and the flame retardant is placed in the pores of the porous body. The compressor according to claim 1, wherein the compressor is contained.
The compressor according to claim 1 or 2, wherein the winding portion of the electric element is formed by winding a conductor wire around a stator core, and the flame retardant is contained in a gap between the conductor wires.
The compressor according to any one of claims 1 to 3, wherein the refrigerating machine oil does not contain an antiwear agent but contains the flame retardant.
The compressor according to any one of claims 1 to 4, wherein the flame retardant is at least one of a halogen flame retardant and a phosphorus flame retardant.
The compressor according to claim 5, wherein an antimony compound is added to the flame retardant.
The ethylene-based fluorinated hydrocarbon contained in the refrigerant is 1,1,2-trifluoroethylene, fluoroethylene, 1,1-difluoroethylene, trans-1,2-difluoroethylene, cis-1, The compressor according to any one of claims 1 to 6, wherein the compressor is at least one of 2-difluoroethylene.
A refrigeration cycle apparatus comprising a refrigerant circuit to which the compressor according to any one of claims 1 to 7 is connected and in which a refrigerant containing an ethylene-based fluorohydrocarbon circulates.