JP2014211093A - Refrigerant compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve such a problem that, when ethylene fluorohydrocarbon where polymerization easily occurs is used as refrigerant, the refrigerant is changed into gas in slide parts of a compressor and a winding part of a motor which are subjected to a high temperature, and so polymerization inhibitor, if added to the refrigerant, is moved out as it is contained in the gas, without being delivered into the slide parts of the compressor and the winding part of the motor, thus making it difficult to sufficiently develop the effects of preventing the polymerization of the refrigerant.SOLUTION: A refrigerant compressor using the ethylene fluorohydrocarbon or mixture containing it as the refrigerant includes: a compression element for compressing the refrigerant; slide components provided in the compression element for constituting the slide parts; and refrigeration oil to be supplied to the slide components for lubricating the slide parts, at least one of the slide components having a sliding surface formed of nonmetal. It uses the refrigerant as well as the refrigeration oil containing the polymerization inhibitor for suppressing the polymerization of the refrigerant.

Description

  The present invention relates to a refrigerant compressor used in a refrigeration air conditioner, and more particularly, to a refrigerant compressor using an ethylene-based fluorinated hydrocarbon or a mixture containing the refrigerant as a refrigerant.

In the field of car air conditioners, as a low GWP (global warming potential) refrigerant, there is HFO-1234yf (CF ₃ CF═CH ₂ ), which is a propylene-based fluorinated hydrocarbon.

  Generally, a propylene-based fluorohydrocarbon having a double bond in the composition has a characteristic that decomposition and polymerization are likely to occur due to the presence of the double bond. For this reason, for example, Patent Document 1 discloses that the surface of the sliding portion, which is likely to be decomposed and polymerized at a high temperature in the compressor, is composed of non-metallic parts, so that the refrigerant is decomposed or polymerized. A method of suppressing this is shown.

  In Patent Document 2, tetrafluoroethylene is useful as a monomer for producing fluororesins and fluorine-containing elastomers having excellent heat resistance and chemical resistance, but it is a substance that is extremely easy to polymerize. Therefore, it is necessary to add a polymerization inhibitor from the production of tetrafluoroethylene, and this technique has been shown.

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

  The HFO-1234yf refrigerant, which is a propylene-based fluorinated hydrocarbon, has a high standard boiling point of -29 ° C., compared to the R410A refrigerant (standard boiling point of −51 ° C.) and the like conventionally used in stationary air conditioners, Low operating pressure and low refrigeration capacity per suction volume. In order to obtain a refrigeration capacity equivalent to that of the R410A refrigerant using the HFO-1234yf refrigerant in a stationary air conditioner, the volume flow rate of the refrigerant must be increased, and the problem for increasing the displacement of the compressor In addition, there are problems of increased pressure loss and decreased efficiency due to an increase in volume flow rate.

  Therefore, in order to apply a low GWP refrigerant for a stationary air conditioner, a low GWP refrigerant having a low standard boiling point is appropriate, and generally, a refrigerant having a lower carbon number tends to be a low boiling refrigerant. is there. Therefore, it is possible to obtain a compound having a lower boiling point, that is, a refrigerant, of the ethylene-based fluorohydrocarbon having 2 carbon atoms than the conventional propylene-based fluorocarbon having 3 carbon atoms.

However, ethylene-based fluorohydrocarbons are more reactive than propylene-based fluorohydrocarbons, are thermally and chemically unstable, and are susceptible to decomposition and polymerization, so that only the method disclosed in Patent Document 1 is used. Therefore, it is difficult to suppress decomposition and polymerization.
In addition, those using ethylene-based fluorinated hydrocarbon as a refrigerant are liable to be decomposed or polymerized immediately after the refrigerant is produced, and decompose or polymerize even during storage. In order to suppress decomposition and polymerization of the refrigerant from the time of storage, a polymerization inhibitor that suppresses the polymerization of the refrigerant as shown in Patent Document 2 from the generation of the refrigerant is used for those using ethylene-based fluorocarbon as a refrigerant. Is added. Therefore, since the polymerization inhibitor is contained in the refrigerant, it was not necessary to add the polymerization inhibitor to the refrigerating machine oil or the like. However, even if a polymerization inhibitor is added to the refrigerant, it circulates in the refrigeration circuit while repeating phase changes with liquid and gas. Then, the refrigerant is vaporized. Since the polymerization inhibitor is added to the vaporized refrigerant and carried away, it has been difficult to sufficiently obtain the effect of preventing the polymerization of the refrigerant without passing over the sliding portion of the compressor and the winding portion of the motor.
In particular, when the sliding parts are made of metal, the sliding surface becomes hot due to the sliding operation, and the metal on the sliding surface is activated. In ethylene-based fluorohydrocarbons, activated metal acts as a reaction catalyst and decomposition is promoted, so if the polymerization inhibitor is insufficient, the formation of polymerized products by decomposition of the decomposition products is also promoted. There was a problem of being done.

  The present invention has been made to solve the above-described problems, and in a refrigerant compressor using ethylene-based fluorohydrocarbon or a mixture containing the same as a refrigerant, the refrigerant at the sliding portion of the compression element An object of the present invention is to provide a refrigerant compressor that suppresses the decomposition of the refrigerant and suppresses the polymerization of the decomposition product of the refrigerant.

  The refrigerant compressor according to the present invention uses ethylene-based fluorocarbon or a mixture containing the refrigerant as a refrigerant, a compression element that compresses the refrigerant, a sliding component that is provided in the compression element and forms a sliding portion, A refrigerating machine oil that is supplied to the sliding part and lubricates the sliding part, and at least one sliding surface of the sliding part is made of a non-metal, and the polymerization prohibition that suppresses the polymerization of the refrigerant with the refrigerating machine oil is prohibited. It is characterized by containing an agent.

  The refrigerant compressor according to the present invention uses ethylene-based fluorocarbon or a mixture containing the refrigerant as a refrigerant, a compression element that compresses the refrigerant, a sliding component that is provided in the compression element and forms a sliding portion, A refrigerating machine oil that is supplied to the sliding part and lubricates the sliding part, and at least one sliding surface of the sliding part is made of a non-metal, and the polymerization prohibition that suppresses the polymerization of the refrigerant with the refrigerating machine oil is prohibited. Since the agent is contained, the temperature rise of the sliding portion of the compression element is suppressed, the activation of the metal on the sliding surface is suppressed, the decomposition of the refrigerant by the activated metal is suppressed, and the polymerization inhibitor for the refrigerating machine oil The polymerization of the decomposition product of the refrigerant can be suppressed.

It is a longitudinal cross-sectional view of the refrigerant compressor which concerns on Embodiment 1 of this invention. 1 is a cross-sectional view of the refrigerant compressor according to Embodiment 1 of the present invention, taken along line AA in FIG. It is a perspective view of the compression element component which concerns on Embodiment 7 of this invention. It is a perspective view of main bearing 4 concerning Embodiment 8 of this invention (a part of main bearing 4 is omitted).

Embodiment 1 FIG.
Hereinafter, an embodiment of the present invention will be described using a rotary compressor as an example of a refrigerant compressor. Although a single cylinder rotary compressor will be described here, a multi-cylinder rotary compressor may be used.

  1 and 2 are diagrams showing Embodiment 1, FIG. 1 is a longitudinal sectional view of a rotary compressor 200, and FIG. 2 is a sectional view taken along line AA of FIG.

  The overall configuration of the rotary compressor 200 will be briefly described.

  An example of the rotary compressor 200 shown in FIG. 1 is a vertical type in which the inside of the sealed container 20 is high pressure. The compression element 101 is housed in the lower part of the sealed container 20. The electric element 102 that drives the compression element 101 is accommodated above the compression element 101 in the upper part of the sealed container 20.

  Refrigerating machine oil 30 that lubricates the sliding portions of the compression element 101 is stored at the bottom of the sealed container 20.

  First, the configuration of the compression element 101 will be described. The cylinder 1 in which the compression chamber is formed has a cylinder chamber 1b whose outer periphery is substantially circular in a plan view and is a space that is substantially circular in a plan view. The cylinder chamber 1b is open at both axial ends. The cylinder 1 has a predetermined axial height in a side view.

  A parallel vane groove 1 a that communicates with a cylinder chamber 1 b that is a substantially circular space of the cylinder 1 and extends in the radial direction is provided so as to penetrate in the axial direction.

  Further, a back pressure chamber 1c, which is a substantially circular space in plan view, communicating with the vane groove 1a is provided on the back surface (outside) of the vane groove 1a.

  A suction port (not shown) through which suction gas from an external refrigeration circuit passes through the cylinder 1 passes from the outer peripheral surface of the cylinder 1 to the cylinder chamber 1b.

  The cylinder 1 is provided with a discharge port (not shown) in which the vicinity of the edge of the circle forming the cylinder chamber 1b, which is a substantially circular space (the end face on the electric element 102 side) is cut out.

  The material of the cylinder 1 is gray cast iron, sintered, carbon steel or the like.

  The rolling piston 2 rotates eccentrically in the cylinder chamber 1b. The rolling piston 2 has a ring shape, and the inner periphery of the rolling piston 2 is slidably fitted to the eccentric shaft portion 6 a of the crankshaft 6.

  It is assembled so that there is always a constant gap between the outer periphery of the rolling piston 2 and the inner wall of the cylinder chamber 1b of the cylinder 1.

  The material of the rolling piston 2 is alloy steel containing chromium or the like.

  The vane 3 is accommodated in the vane groove 1a of the cylinder 1, and the vane 3 is always pressed against the rolling piston 2 by the vane spring 8 provided in the back pressure chamber 1c. Since the rotary compressor 200 has a high pressure inside the sealed container 20, when the operation is started, the force due to the differential pressure between the high pressure in the sealed container 20 and the pressure in the cylinder chamber 1b on the back surface of the vane 3 (on the back pressure chamber 1c side). Therefore, the vane spring 8 is used mainly for the purpose of pressing the vane 3 against the rolling piston 2 when the rotary compressor 200 is activated (the pressure in the sealed container 20 and the cylinder chamber 1b is not different). .

  The shape of the vane 3 is a flat shape (the thickness in the circumferential direction is smaller than the length in the radial direction and the axial direction).

  High-speed tool steel is mainly used as the material of the vane 3.

  The main bearing 4 is slidably fitted to a main shaft portion 6b (a portion above the eccentric shaft portion 6a) of the crankshaft 6, and one end face of the cylinder chamber 1b (including the vane groove 1a) of the cylinder 1 ( The electric element 102 side) is closed.

  The main bearing 4 includes a discharge valve (not shown). However, it may be attached to either one or both of the main bearing 4 and the sub-bearing 5.

  The main bearing 4 has a substantially inverted T shape when viewed from the side.

  The sub-bearing 5 is slidably fitted to the sub-shaft portion 6c (a portion below the eccentric shaft portion 6a) of the crankshaft 6, and the other end face of the cylinder chamber 1b (including the vane groove 1a) of the cylinder 1. (Refrigerating machine oil 30 side) is closed.

  The secondary bearing 5 is substantially T-shaped in a side view.

  The material of the main bearing 4 and the sub bearing 5 is the same as that of the cylinder 1, and is made of gray cast iron, sintered, carbon steel, or the like.

  A discharge muffler 7 is attached to the main bearing 4 on the outer side (electric element 102 side). The high-temperature and high-pressure discharge gas discharged from the discharge valve of the main bearing 4 enters the discharge muffler 7 at one end and is then discharged from the discharge muffler 7 into the sealed container 20. However, the discharge muffler 7 may be provided on the sub-bearing 5 side.

  A suction muffler 21 is provided beside the hermetic container 20 to suck low-pressure refrigerant gas from the refrigeration circuit and prevent liquid refrigerant from being directly sucked into the cylinder chamber of the cylinder 1 when the liquid refrigerant returns. The suction muffler 21 is connected to the suction port of the cylinder 1 via the suction pipe 22. The main body of the suction muffler 21 is fixed to the side surface of the sealed container 20 by welding or the like.

  Next, the configuration of the electric element 102 will be described. The electric element 102 is a brushless DC motor, but may be an induction motor.

  The electric element 102 includes a stator 12 and a rotor 13. The stator 12 is fitted and fixed to the inner peripheral surface of the hermetic container 20, and the rotor 13 is disposed inside the stator 12 via a gap.

  The stator 12 is a stator core 12a manufactured by punching a magnetic steel sheet having a thickness of 0.1 to 1.5 mm into a predetermined shape, laminating a predetermined number of sheets in the axial direction, and fixing by caulking or welding, A three-phase winding 12b wound around a plurality of teeth (not shown) of the stator core 12a by a concentrated winding method is provided. The winding 12b is wound around the tooth portion via the insulating member 12c. The material of the winding 12b is a copper wire coated with a coating such as AI (amidoimide) / EI (ester imide). As the insulating member 12c, PET (polyethylene terephthalate), PBT (polybutylene terephthalate), FEP (tetrafluoroethylene / hexafluoropropylene copolymer (4.6 fluoride)), PFA (tetrafluoroethylene / perfluoroalkyl vinyl ether) Copolymer), PTFE (polytetrafluoroethylene), LCP (liquid crystal polymer), PPS (polyphenylene sulfide), phenol resin, and the like are mainly used.

  A part of the winding 12b protrudes from both axial ends of the stator core 12a (upper and lower ends in the axial direction in FIG. 1). This protruding portion is called a coil end. A portion indicated by reference numeral (12b) in FIG. 2 is a coil end on one side (the anti-compression element 101 side) of the winding 12b. The lead wire 23 is connected to a terminal (not shown) attached to the insulating member 12c.

  On the outer periphery of the stator core 12a, notches (not shown) arranged at substantially equal intervals are provided at a plurality of locations. This notch is one of the paths of the discharge gas discharged from the discharge muffler 7 into the sealed container 20, and also serves as a path for the refrigerating machine oil 30 to return from the top of the electric element 102 to the bottom of the sealed container 20.

  The rotor 13 disposed inside the stator 12 via a gap (usually about 0.3 to 1 mm) is made of an electromagnetic steel plate having a thickness of 0.1 to 1.5 mm, similar to the stator core 12a. It is punched into a shape, laminated in a predetermined number of axial directions, and inserted into a rotor core 13a manufactured by fixing by caulking or welding and a permanent magnet insertion hole (not shown) formed in the rotor core 13a. A permanent magnet (not shown). For permanent magnets, ferrite or rare earth magnets are used.

  In order to prevent the permanent magnet inserted into the permanent magnet insertion hole from coming off in the axial direction, end plates are provided at both ends in the axial direction of the rotor 13 (upper and lower ends in the axial direction in FIG. 1). An upper end plate 13 b is provided at the upper end portion in the axial direction of the rotor 13, and a lower end plate 13 c is provided at the lower end portion in the axial direction of the rotor 13.

  The upper end plate 13b and the lower end plate 13c also serve as a rotation balancer. The upper end plate 13b and the lower end plate 13c are fixed by caulking together with a plurality of fixing rivets (not shown).

  The rotor core 13a is provided with a plurality of through-holes (not shown) penetrating in the substantially axial direction serving as a gas flow path for the discharge gas.

  A terminal 24 (referred to as a glass terminal) connected to a power source that is a power supply source is fixed to the sealed container 20 by welding. In the example of FIG. 1, the terminal 24 is provided on the upper surface of the sealed container 20. A lead wire 23 from the electric element 102 is connected to the terminal 24.

  A discharge pipe 25 having both ends opened is inserted into the upper surface of the sealed container 20. The discharge gas discharged from the compression element 101 is discharged from the sealed container 20 through the discharge pipe 25 to the external refrigeration circuit.

  When the electric element 102 is composed of an induction motor, electromagnetic steel sheets having a thickness of 0.1 to 1.5 mm are punched into a predetermined shape, laminated in a predetermined number of axes, and fixed by caulking or welding. A rotor core 13a manufactured in this manner, and a squirrel-cage winding in which a conductor formed of aluminum or copper is filled or inserted into a slot formed in the rotor core 13a and both ends of the conductor are short-circuited by end rings, Is provided.

  As the refrigerating machine oil 30 stored at the bottom in the sealed container 20, POE (polyol ester), PVE (polyvinyl ether), AB (alkyl benzene) or the like, which is a synthetic oil, is used. The viscosity of the oil is selected to be sufficient for lubricating the rotary compressor 200 including the melting of the refrigerant into the oil and not reducing the efficiency of the rotary compressor 200. Generally, the viscosity of the base oil (40 At a temperature of about 5 to 300 [cSt].

  The refrigerating machine oil contains 0.1% to 5% of limonene as a polymerization inhibitor for the refrigerant.

  As the refrigerant used in this compressor, trans-1,2, difluoroethylene (R1132 (E)), which is a low boiling point refrigerant, is used as in R410A.

  A general operation of the rotary compressor 200 will be described. When electric power is supplied from the terminal 24 and the lead wire 23 to the stator 12 of the electric element 102, the rotor 13 rotates. Then, the crankshaft 6 fixed to the rotor 13 rotates, and accordingly, the rolling piston 2 rotates eccentrically in the cylinder chamber 1b of the cylinder 1. A space between the cylinder chamber 1 b of the cylinder 1 and the rolling piston 2 is divided into two by a vane 3. As the crankshaft 6 rotates, the volume of these two spaces changes. The volume gradually increases on one side, and the refrigerant is sucked from the suction muffler 21, while the volume gradually decreases on the other side. The refrigerant gas is compressed. The compressed discharge gas is discharged once from the discharge muffler 7 into the sealed container 20, passes through the electric element 102, and is discharged out of the sealed container 20 through the discharge pipe 25 on the upper surface of the sealed container 20.

  The discharge gas passing through the electric element 102 is disposed in a through hole of the rotor 13 of the electric element 102, a gap including a slot opening (not shown, also referred to as a slot opening) of the stator core 12a, and an outer periphery of the stator core 12a. Pass through the cutouts made.

When the rotary compressor 200 performs the above operation, there are a plurality of sliding portions where the components slide as shown below.
(1) First sliding portion: outer periphery 2a of rolling piston 2 and tip 3a (inner side) of vane 3;
(2) Second sliding portion: vane groove 1a of cylinder 1 and side surface portion 3b (both side surfaces) of vane 3;
(3) Third sliding part: the inner periphery 2b of the rolling piston 2 and the eccentric shaft part 6a of the crankshaft 6;
(4) Fourth sliding portion: inner periphery of main bearing 4 and main shaft portion 6b of crankshaft 6;
(5) Fifth sliding portion: the inner periphery of the auxiliary bearing 5 and the auxiliary shaft portion 6c of the crankshaft 6.

The parts constituting the sliding portion provided in the compression element 101 are collected.
(1) Cylinder 1;
(2) Rolling piston 2;
(3) Vane 3;
(4) Main bearing 4;
(5) Sub bearing 5;
(6) Crankshaft 6.

  Although not shown, when the drive shaft is driven, the protruding tip of the vane 3 provided integrally with the rolling piston 2 enters and exits along the receiving groove of the support, and at the same time, the support turns. That is, the vane 3 is a swing-type rotary compressor that always divides the inside of the cylinder chamber 1b into a compression chamber and a suction chamber by moving back and forth in the radial direction while swinging according to the revolution of the rolling piston 2. .

  In this swing type rotary compressor, the projecting tip of the vane 3 and the receiving groove of the support serve as a sliding part.

  In addition, a cylindrical cylindrical holding hole is formed at an intermediate portion between the suction port and the discharge port of the cylinder 1, and the cylindrical holding hole is constituted by two semi-cylindrical members having a semicircular cross section. Since the supporting body is rotatably fitted, the outer peripheral surface of the supporting body and the cylindrical holding hole of the cylinder become another sliding portion.

  Since this embodiment uses trans-1,2, difluoroethylene (R1132 (E)) as a refrigerant, the refrigerant is thermally and chemically unstable, and decomposition or polymerization due to a chemical reaction occurs. It's easy to do. When polymerization of the refrigerant occurs and a polymer is generated, the polymer may be clogged in the compressor or the refrigeration circuit. In particular, the chemical reaction of the refrigerant is promoted at a portion where the temperature is high, and polymerization is likely to occur. Therefore, in order to suppress the polymerization of the refrigerant, it is necessary to take measures such as attaching a polymerization inhibitor to the high temperature part.

  The sliding part of the compression element and the winding part of the electric element described above are parts that become high temperature in the compressor. The sliding portion of the compression element generates heat when the components constituting the compression element slide, and the winding portion of the electric element generates heat when current flows through the winding to rotate the rotor 13. .

  Ethylene-based fluorohydrocarbons are highly reactive and cause decomposition and polymerization even during storage at room temperature. For this reason, a polymerization inhibitor that suppresses the polymerization of the refrigerant from the time of refrigerant generation is added to the refrigerant that uses ethylene-based fluorohydrocarbon as a refrigerant. Is mixed with a polymerization inhibitor. It is not used or stored in a state where the ethylene-based fluorohydrocarbon and the polymerization inhibitor are separated. However, since the decomposition of the refrigerant proceeds by sliding between the metals in the compressor, there is a high opportunity for the decomposition product to polymerize, and even if a polymerization inhibitor is added to the refrigerant, the sliding part of the high-temperature compression element or the electric motor In the winding part of the element, the refrigerant is vaporized, and the polymerization inhibitor is also carried out together with the refrigerant turned into a gas, so that it does not remain on the sliding part of the hot compression element and the winding part of the electric element, and the polymerization inhibitor is sufficient. Effect cannot be demonstrated.

  On the other hand, the refrigerating machine oil 30 stored in the airtight container 20 is supplied to each sliding portion of the compressor by an oil supply mechanism (not shown) provided in the compression element. Lubricating. Generally, the refrigerant and the refrigerating machine oil are stored and transported separately, and the refrigerant and the refrigerating machine oil are enclosed in the compressor and the refrigerating circuit when the air conditioner is assembled. Therefore, even if a polymerization inhibitor that suppresses the polymerization of a refrigerant such as limonene is added to the refrigeration oil, the refrigeration oil and the refrigerant do not mix with each other. There was no suppression, and there was no need to add a polymerization inhibitor to the refrigeration oil. In addition, even after the refrigerant and refrigeration oil are sealed in the compressor and the refrigeration circuit, when the compressor is stopped, the refrigerant that can move freely as a gas in the refrigeration circuit is stored at the bottom of the sealed container and freely For refrigerating machine oil that cannot be moved, even if a polymerization inhibitor is added, the refrigerating machine oil and refrigerant do not mix, so the polymerization inhibitor does not act on the refrigerant and suppress polymerization, and is added to the refrigerant. Was sufficient, and it was not necessary to add a polymerization inhibitor to the refrigerating machine oil. However, when the compressor is in operation, the polymerization inhibitor is added to the refrigerating machine oil, so that the polymerization inhibitor can be supplied to the sliding part together with the refrigerating machine oil, and the sufficient polymerization inhibitor is held in the sliding part. Will be able to. Thereby, even if a sliding part becomes high temperature, superposition | polymerization of a refrigerant | coolant can be suppressed and a polymerization inhibitor comes to exhibit. Further, the high-temperature refrigerant compressed by the compression element passes through the electric element 102 as described above and is discharged out of the sealed container 20 from the discharge pipe 25 on the upper surface of the sealed container 20. At this time, since the flow of the refrigerant is fast, a part of the refrigerating machine oil containing limonene is also conveyed to the electric element portion while being dissolved in the refrigerant. The refrigerant carried to the electric element part collides with the electric element part. At that time, the refrigerant and the refrigerating machine oil are separated, the refrigerant flows to the upper discharge pipe 25 side, and the refrigerating machine oil stores the refrigerating machine oil. Go back to the bottom of the sealed container. A part of the separated refrigerating machine oil adheres to the winding of the electric element when it collides with the electric element part, and is temporarily held. As a result, the polymerization of the refrigerant can be suppressed even when the temperature of the winding becomes high, and the polymerization inhibitor is exerted.

From the above, sufficient polymerization inhibitor can be obtained by supplying refrigerating machine oil containing limonene, which is a polymerization inhibitor, to the sliding part of the compression element and the winding part of the electric element that become high temperature in the compressor. Can be held.
In addition, the polymerization inhibitor contained in the refrigerant acts on the vaporized refrigerant, which is effective in suppressing the polymerization of the refrigerant.

  Thereby, in the high temperature part which is easy to generate | occur | produce polymerization, superposition | polymerization can be prevented with the refrigerating machine oil containing limonene, and sufficient reliability can be maintained even if it uses the refrigerant | coolant which is easy to generate | occur | produce polymerization.

  On the other hand, when the sliding portion of the compression element is made of metal, the sliding surface becomes hot due to sliding of the metals, and the metal on the sliding surface is activated. In a thermally and chemically unstable refrigerant, the activated metal surface of the sliding part acts as a reaction catalyst, inducing decomposition. Furthermore, in the decomposed decomposition product, the exposed metal active surface serves as a polymerization catalyst, and the generation of the polymer product is promoted. Although the polymerization inhibitor suppresses the polymerization of the decomposition product, the action of the polymerization inhibitor can be further enhanced by suppressing the decomposition of the refrigerant. That is, the catalytic action can be suppressed by suppressing exposure of the activated metal surface at the sliding portion of the compression element.

  As shown below, at least one of the two parts constituting the sliding portion is made of a non-metallic material. By using one of the sliding parts as a non-metallic material having a large specific heat, temperature rise can be suppressed as compared with sliding between metals, and activation of the metal surface of the sliding part can be suppressed. Thereby, decomposition | disassembly and superposition | polymerization of a refrigerant | coolant can be suppressed.

  First, a carbon-based DLC-Si (diamond-like carbon-silicon) coating (an example of a non-metal) is applied to the surface of the vane 3 at the outer periphery of the rolling piston 2 that is the first sliding portion and the tip 3a of the vane 3. It has been applied. For this reason, the sliding between the outer periphery of the rolling piston 2 and the tip 3a of the vane 3 can avoid direct contact between metals, is not likely to be in a high temperature condition, and the metal surface is not easily activated. Polymerization can be suppressed.

  The DLC-Si coating is amorphous carbon containing silicon, the surface layer hardness is 2000 to 2500 Hmv, and the film thickness is about 3 μm.

  Also in the vane groove 1a of the cylinder 1 which is the second sliding portion and the side surface portion 3b of the vane 3, the surface of the vane 3 is coated with DLC-Si to avoid direct contact between metals. Since the metal surface is hardly activated and is not easily subjected to high temperature conditions, polymerization of the refrigerant can be suppressed.

  In the inner periphery 2b of the rolling piston 2, which is the third sliding portion, and the eccentric shaft portion 6a of the crankshaft 6, a manganese phosphate film (an example of a nonmetal) is formed on the surface of the crankshaft 6, thereby forming a metal The direct contact between each other can be avoided, and the metal surface is hardly activated and is not easily subjected to a high temperature condition, so that the polymerization of the refrigerant can be suppressed. A manganese phosphate coating may be formed on the inner periphery 2b of the rolling piston 2.

  In the inner periphery of the main bearing 4 that is the fourth sliding portion, the main shaft portion 6b of the crankshaft 6, the inner periphery of the auxiliary bearing 5 that is the fifth sliding portion, and the auxiliary shaft portion 6c of the crankshaft 6, By forming a manganese phosphate film on the surface of the shaft 6, direct contact between metals can be avoided, and the metal surface is also hardly activated and is not easily subjected to high-temperature conditions, thereby suppressing the polymerization of the refrigerant. Can do. A manganese phosphate coating may be formed on the inner periphery of the main bearing 4 and the sub-bearing 5.

By configuring as described above, it is possible to prevent direct contact between metals in each sliding portion in the rotary compressor 200, and the metal surface which is a sliding surface is also activated and the sliding portion is Since high temperature can be suppressed, decomposition and polymerization of the refrigerant can be suppressed, failure of the rotary compressor 200 and clogging in the refrigeration circuit due to the refrigerant polymer can be suppressed, and long-term reliability can be obtained.
In addition, it is not necessary to perform non-metalization in all the sliding parts mentioned above. Activation of the metal surface is also more likely to occur in areas where the surface pressure of the sliding part is large, the sliding speed is fast, and the state of lubrication is poor. Decomposition and polymerization can be suppressed, and a work process for non-metalization can be omitted. In places where the surface pressure of the sliding part is low, the sliding speed is slow, or the lubrication state is good, even if the sliding parts are made of metal, the metal on the sliding surface is difficult to activate. There is no need for metallization.
In addition, by preventing direct contact between metals, it is possible to suppress the decomposition of the refrigerant and to suppress the decomposition of the decomposition product decomposed by the polymerization inhibitor contained in the refrigerator oil. As a result, the production of the polymer can be further suppressed and high reliability can be obtained.

  In the above description, an example in which trans-1,2, difluoroethylene (R1132 (E)) is used as the refrigerant has been shown. However, fluoroethylene (R1141), cis-1,2 difluoroethylene (R1132 (Z)), The same effect can be obtained by using 1,1 difluoroethylene (R1132a), 1,1,2 trifluoroethylene (R1123) or the like.

  In the above description, limonene is used as the polymerization inhibitor contained in the refrigerating machine oil. Good.

Embodiment 2. FIG.
In the first embodiment, the method of preventing the polymerization of the refrigerant by sufficiently presenting the refrigerating machine oil containing the polymerization inhibitor in the portion where the temperature becomes high is shown. However, the polymerization inhibitor is previously added to the sliding part. It can also be contained. The method will be described.

  The cylinder 1, the main bearing 4, and the sub-bearing 5 shown in the first embodiment can be composed of sintered parts that are porous. These sintered parts are impregnated with a polymerization inhibitor or a refrigerating machine oil containing a polymerization inhibitor in advance before assembling the compressor. As a result, there is an effect of further enhancing the effect of suppressing the polymerization of the refrigerant by allowing the polymerization inhibitor to ooze out from the sintered part in the compressor cylinder and the sliding portion that are likely to become high temperature.

  As a result, even if the refrigerant polymerization conditions are met in a state where the refrigerating machine oil to the sliding portion of the compression element is not sufficient, the polymerization of the refrigerant can be suppressed by the held polymerization inhibitor.

Embodiment 3 FIG.
Also in the winding part of the electric element that tends to be high temperature other than the sliding part, a polymerization inhibitor can be contained in advance as in the second embodiment. The method will be described.

  In the winding portion 12b of the electric element, in the winding having a circular cross section, a gap is generated between the windings. The gap between the windings can contain and hold a polymerization inhibitor or a refrigerating machine oil containing a polymerization inhibitor, similarly to the porous structure of the sintered part. For example, a polymerization inhibitor is contained in the processing oil used in the winding process, or the winding is immersed in the polymerization inhibitor. As a result, the polymerization inhibitor in the winding portion 12b is sufficiently supplied to the winding portion where the polymerization occurs, thereby enhancing the effect of suppressing the polymerization of the refrigerant.

  As a result, even when the refrigerant polymerization conditions are complete in a state where the refrigerating machine oil to the winding part sliding portion of the electric element is not sufficient, the polymerization inhibitor that is held in place suppresses the polymerization of the refrigerant. it can.

Embodiment 4 FIG.
In the first embodiment, an example of a method for avoiding contact between metals for each of the five sliding portions and suppressing activation of the metal surface and high temperature of the sliding portion has been described. In addition to the method of the first embodiment, there are several types of methods to obtain. In the fourth embodiment, other examples of the outer periphery 2a of the rolling piston 2 and the tip 3a of the vane 3 as the first sliding portion will be described.

  In the first embodiment, the method of applying the DLC-Si coating to the vane 3 has been described. As the coating applied to the vane 3, DLC (diamond-like carbon), CrN (chromium nitride), TiN (titanium nitride), TiCN ( Titanium carbonitride), TiAlN (titanium nitride aluminum), WC / C (tungsten carbide coating), VC (vanadium carbide), etc. may be used, and the metal is not exposed on the sliding surface of the vane. The same effects as in the fourth embodiment are shown.

In addition to the method of covering the metal surface with a non-metallic coating as described above, there is a method of using the vane 3 itself as a ceramic material. Materials include SiC (silicon carbide), ZrO ₂ (zirconium dioxide), Al ₂ O ₃ (aluminum oxide), Si ₃ N ₄ (silicon nitride), etc., and by using these, the sliding surface of the vane 3 Since the metal is not exposed, the same effect as in the first embodiment can be obtained.

  In the first embodiment, the method in which the metal surface is not exposed on the surface of the vane 3 is shown. However, the same method may be performed on the outer periphery 2 a of the rolling piston 2. By coating the surface including the outer periphery 2a of the rolling piston 2 with DLC-Si, DLC, CrN, TiN, TiCN, TiAlN, WC / C, VC, etc., metal is applied to the sliding surface of the outer periphery 2a of the rolling piston 2. Since it is not exposed, the same effect as in the first embodiment is obtained.

In addition, the rolling piston 2 includes not only a method of covering the metal surface with a non-metallic coating, but also a method of using the material of the rolling piston 2 itself as a ceramic material. As the material, SiC, ZrO ₂ , Al ₂ O ₃ , Si ₃ N ₄ or the like can be applied, and the metal is not exposed on the sliding surface of the outer periphery 2a of the rolling piston 2, so the same effect as in the first embodiment. There is.

Embodiment 5. FIG.
Similarly to the fourth embodiment, as a fifth embodiment, an example in the vane groove 1a of the cylinder 1 which is the second sliding portion and the side surface portion 3b of the vane 3 is shown. As in the fourth embodiment, the vane 3 can be coated with DLC, CrN, TiN, TiCN, TiAlN, WC / C, VC, or the like. Thereby, since it can prevent that a metal is exposed to the sliding surface of the vane 3 also in a 2nd sliding part, the effect similar to Embodiment 1 can be acquired. Moreover, since the material of the vane 3 is a ceramic such as SiC, ZrO ₂ , Al ₂ O ₃ , Si ₃ N ₄ or the like, the metal is not exposed on the sliding surface of the vane 3 even in the second sliding portion. The same effects as those of the first embodiment can be obtained.

Embodiment 6 FIG.
As the sixth embodiment, other examples of the inner periphery 2b of the rolling piston 2 and the eccentric shaft portion 6a of the crankshaft 6 as the third sliding portion will be described.

  FIG. 3 is a perspective view of the rolling piston 2 showing the sixth embodiment.

  In the first embodiment, a method of forming a manganese phosphate film on the surface of the crankshaft 6 has been shown. However, a countermeasure may be taken on the rolling piston 2 side, for example, as shown in FIG. There is also a method of using a bearing material 9 for the inner diameter portion.

  There are two types of the bearing material 9, metal type and resin type (non-metal type), but the resin type bearing material 9 (an example of non-metal) meets the gist of the present embodiment.

  Specifically, it is desirable to use the bearing material 9 mainly composed of PTFE (polytetrafluoroethylene) and POM (polyacetal) as the resin-based bearing material 9. Thereby, since the metal is not exposed to the sliding portion on the inner diameter side of the rolling piston, the same effect as in the first embodiment can be obtained.

  Note that a bearing material 9 (an example of a nonmetal) may be used for the eccentric shaft portion 6 a of the crankshaft 6.

Embodiment 7 FIG.
As the seventh embodiment, the inner periphery of the main bearing 4 that is the fourth sliding portion, the main shaft portion 6b of the crankshaft 6, the inner periphery of the auxiliary bearing 5 that is the fifth sliding portion, and the auxiliary shaft of the crankshaft 6 are used. The other Example in the axial part 6c is shown.

  FIG. 4 is a diagram showing the seventh embodiment, and is a perspective view of the main bearing 4 (a part of the main bearing 4 is omitted).

  In the first embodiment, the method of forming the manganese phosphate coating on the surface of the crankshaft 6 has been described. However, measures may be taken on the main bearing 4 and the sub-bearing 5 side, for example, as shown in FIG. There is also a method of using a bearing material 10 (an example of a nonmetal) for the inner diameter portion of the main bearing 4.

  There are two types of the bearing material 10, that is, a metal-based material and a resin-based material. The resin-based bearing material 10 is suitable for the gist of the present embodiment.

  Specifically, it is desirable to use a bearing material 10 mainly composed of PTFE and POM as the resin-based bearing material 10. Thereby, since the metal is not exposed to the sliding portion on the inner diameter side of the main bearing 4, the same effect as in the fourth embodiment can be obtained.

  The bearing material 10 can also be used for the main shaft portion 6b and the sub shaft portion 6c of the crankshaft 6.

  In the above description, an example has been described in which at least one of the components constituting the sliding portion is made of a non-metal at least the sliding surface, but at least both of the components constituting the sliding portion are slid. The surface to be made may be made of a non-metal.

Embodiment 8 FIG.
The refrigerating machine oil used in the above embodiments generally contains an antiwear agent. The antiwear agent has a function of preventing wear of sliding parts by being decomposed by itself, but the decomposition product of the antiwear agent is a decomposition product of ethylene-based fluorocarbon hydrogen or a mixture thereof that is easily polymerized and decomposed. It is known to react to produce solids. This solid matter accumulates in a thin flow path such as an expansion valve or a capillary tube in the refrigeration cycle, which may cause clogging and cause poor cooling. In this embodiment, since the refrigeration oil was appropriately selected so as not to contain the antiwear agent, the solids produced by the reaction between the decomposition product of the wear part inhibitor and the decomposition product of the ethylene-based fluorohydrocarbon and the mixture thereof were used. It is possible to obtain a refrigerant compressor that can maintain good performance over a long period of time without generation of substances and clogging on the refrigeration circuit.

  1 cylinder, 1a vane groove, 1b cylinder chamber, 1c back pressure chamber, 2 rolling piston, 2a outer periphery, 2b inner periphery, 3 vane, 3a tip, 3b side surface portion, 4 main bearing, 5 sub bearing, 6 crankshaft, 6a Eccentric shaft part, 6b Main shaft part, 6c Subshaft part, 7 Discharge muffler, 8 Vane spring, 9 Bearing material, 10 Bearing material, 12 Stator, 12a Stator iron core, 12b Winding, 12c Insulating member, 13 Rotor, 13a Rotor core, 13b Top plate, 13c Bottom plate, 20 Sealed container, 21 Suction muffler, 22 Suction pipe, 23 Lead wire, 24 Terminal, 25 Discharge pipe, 30 Refrigerating machine oil, 101 Compression element, 102 Electric element, 200 Rotary Compressor.

Claims (17)

In a refrigerant compressor that compresses ethylene-based fluorocarbon or a mixture containing the same as a refrigerant,
A compression element for compressing the refrigerant;
A sliding component provided on the compression element and constituting a sliding portion;
A refrigerating machine oil that is supplied to the sliding part and lubricates the sliding part,
A refrigerant compressor characterized in that at least one sliding surface of the sliding component is made of a non-metal, and the refrigerating machine oil contains a polymerization inhibitor that suppresses polymerization of the refrigerant. In a refrigerant compressor that compresses ethylene-based fluorocarbon or a mixture containing the same as a refrigerant,
A compression element for compressing the refrigerant;
A sliding part provided on the compression element and constituting a sliding part,
The sliding component is composed of a sintered component, and the sintering component contains a polymerization inhibitor that suppresses polymerization of the refrigerant, and at least one sliding surface of the sliding component is composed of a nonmetal. A refrigerant compressor characterized by that. In a refrigerant compressor that compresses ethylene-based fluorocarbon or a mixture containing the same as a refrigerant,
A compression element for compressing the refrigerant;
An electric element for driving the compression element;
A sliding part provided on the compression element and constituting a sliding part,
The electric element has a winding, a gap between the windings contains a polymerization inhibitor that suppresses polymerization of the refrigerant, and at least one sliding surface of the sliding component is made of a non-metal. A refrigerant compressor characterized by. The ethylene-based fluorocarbon hydrogen is fluoroethylene (R1141), trans-1,2 difluoroethylene (R1132 (E)), cis-1,2 difluoroethylene (R1132 (Z)), 1,1 difluoroethylene (R1132a). ), 1,1,2, trifluoroethylene (R1123). 4. The refrigerant compressor according to claim 1, wherein the refrigerant compressor is at least one of R1,123 and R1,123. The refrigerant compressor according to claim 1, wherein the polymerization inhibitor is a terpene compound. 6. The refrigerant compressor according to claim 5, wherein the terpene compound is at least one of limonene, pinene, camphene, cymene, terpinene, citronellol, tilpineol, and borneol. The refrigerant compressor according to claim 1, wherein the nonmetal is formed by performing a coating process on a surface of the sliding component. The coating treatment includes DLC (diamond-like carbon), DLC-Si (diamond-like carbon-silicon), CrN (chromium nitride), TiN (titanium nitride), TiCN (titanium carbonitride), TiAlN (titanium nitride aluminum), WC The refrigerant compressor according to claim 7, wherein the refrigerant compressor is any one of / C (tungsten carbide coating) and VC (vanadium carbide). The refrigerant compressor according to any one of claims 1 to 6, wherein the nonmetal is formed of a nonmetallic bearing material. The refrigerant compressor according to claim 9, wherein the non-metallic bearing material includes PTFE (polytetrafluoroethylene) and POM (polyacetal) as main components. The refrigerant compressor according to any one of claims 1 to 6, wherein at least one of the parts constituting the sliding portion is made of a ceramic material. 12. The ceramic material is any one of SiC (silicon carbide), ZrO ₂ (zirconium dioxide), Al ₂ O ₃ (aluminum oxide), and Si ₃ N ₄ (silicon nitride). The described rotary compressor. The refrigerant compressor according to any one of claims 1 to 6, wherein the nonmetal is constituted by a manganese phosphate coating. The compression element includes a ring-shaped rolling piston that rotates eccentrically in a cylinder chamber of a cylinder, and a vane that is housed in a vane groove of the cylinder and is pressed against the rolling piston and slides in the vane groove. ,
The refrigerant compressor according to claim 1, wherein the sliding portion is a tip of the vane and an outer periphery of the rolling piston. The compression element includes a cylinder having a vane groove, and a vane housed in the vane groove of the cylinder and sliding in the vane groove,
The refrigerant compressor according to claim 1, wherein the sliding portion is the vane groove and the vane. The compression element includes a ring-shaped rolling piston that rotates eccentrically in a cylinder chamber of a cylinder, and a crankshaft having an eccentric shaft portion that is eccentric from the main shaft portion,
14. The refrigerant compressor according to claim 1, wherein the sliding portion is an inner periphery of the rolling piston and the eccentric shaft portion of the crankshaft. The compression element includes a crankshaft having a main shaft portion and a subshaft portion, a main bearing that is slidably fitted to the main shaft portion of the crankshaft, and a slidable portion on the subshaft portion of the crankshaft. A secondary bearing to be fitted,
The refrigerant compressor according to any one of claims 1 to 6, 9, 10, and 13, wherein the sliding portions are the main bearing, the sub bearing, and the crankshaft.

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