JPWO2014136207A1 - Compressor - Google Patents

Abstract

There is provided a sealed container 10 having a suction pipe 12 for sucking fluid, a compression mechanism section 30 for compressing fluid sucked from the suction pipe 12, and a discharge pipe 13 for discharging fluid compressed by the compression mechanism section 30. The low-pressure container type scroll compressor 1 is provided with lubricating oil together with the fluid sucked from the suction pipe 12 in the sealed container 10, and the fluid is R32 refrigerant or a mixed refrigerant containing 51% or more of R32 refrigerant. Yes, the lubricating oil is an ester oil or an ether oil.

Description

  The present invention relates to a compressor that compresses and discharges a fluid.

  Conventional compressors, for example, scroll compressors, are roughly classified into two types depending on the pressure range when used in refrigeration and air conditioning equipment. One is a high-pressure vessel type (sometimes called a high-pressure dome type) in which the atmosphere of the refrigeration oil in the compressor is filled with the discharge gas, and the other is the atmosphere of the refrigeration oil in the compressor filled with the intake gas. Low pressure container type (sometimes called low pressure dome type). In these two types, the ambient temperature of the refrigerating machine oil used as the lubricating oil is different from each other. Refrigerating machine oils are used by adjusting the viscosity grade for each type of compressor because the viscosity varies greatly with temperature. When the refrigerant oil that is compatible with the refrigerant is selected as the refrigerating machine oil, the oil concentration depends on the pressure and temperature of the atmosphere of the refrigerating machine oil. Therefore, it is necessary to clearly define the oil concentration (for example, see Patent Document 1) .

  In addition, in the case of an R32 refrigerant or a mixed refrigerant containing 51% or more of an R32 refrigerant, which is said to be a low GWP (global warming potential) refrigerant, when used together with a conventional refrigerator oil, the refrigerant and the oil are easily separated at a low temperature. There was a feature.

Japanese Patent No. 3956589

  In a conventional scroll compressor, when refrigerating machine oil (ester oil or ether oil) existing in the world is used, the mixed refrigerant containing 51% or more of R32 refrigerant or R32 refrigerant is R410A refrigerant containing 50% of R32 refrigerant. Compared to refrigeration oil at low temperatures, it becomes easier to separate. The temperature at which the separation begins is higher as the viscosity grade of the refrigerating machine oil is higher. For example, in the case of ether oil of viscosity grade (ISO VG) 68, the oil is separated from the refrigerant at around 0 ° C. In this case, the oil that has been discharged from the compressor to the refrigerant circuit is separated from the refrigerant and stays at a low temperature portion such as a reservoir or an evaporator in the refrigerant circuit, and does not return to the compressor. As a result, the lubricating oil in the compressor becomes insufficient, and compressor seizure occurs. Moreover, it is difficult to establish a refrigeration cycle in a building air conditioner with a long refrigerant circuit or a refrigerated refrigerator that is used at a lower temperature than the air conditioner.

  Moreover, the refrigerant temperature after compression tends to increase as the proportion of the R32 refrigerant increases. For this reason, in the high-pressure vessel type in which the refrigeration oil is present in the space filled with the discharge gas, a higher viscosity grade refrigeration oil is selected.

An example of selecting such a high viscosity grade refrigerating machine oil is given below. The atmospheric temperature of the low pressure container type refrigerating machine oil is 10 to 80 ° C., and the high pressure container type refrigerating machine oil is 50 to 120 ° C. At this time, for example, in order to ensure the oil viscosity (kinematic viscosity) of 10 mm ² / s, it is necessary to select 32 grades for the low pressure container type and 68 grade for the high pressure container type as the viscosity grade of the refrigerating machine oil. When 32 grade refrigerating machine oil is used in the high pressure container type, the viscosity is reduced to half and becomes less than 10 mm ² / s, so that the lubricity of the sliding portion may not be satisfied.

  In other words, in conventional high-pressure container type scroll compressors, when low-viscosity grade refrigerator oil is used so that the refrigerant and oil melt at low temperatures, the lubrication of the sliding parts is ensured because the temperature of the refrigerator oil atmosphere is high. Insufficient oil viscosity. On the other hand, when a high-viscosity grade refrigerating machine oil that can ensure the lubricity of the sliding portion is used, the refrigerant and the oil do not melt at low temperatures and are easily separated. As a result, since the oil discharged from the compressor into the refrigerant circuit stays in the refrigerant circuit, there is a problem that compressor seizure occurs due to insufficient lubricating oil.

  The present invention has been made to solve the above-described problems, can prevent the refrigerant and the lubricating oil from separating at a low temperature, and ensure the lubricity of the sliding portion. It is an object of the present invention to provide a compressor that can handle the above.

  A compressor according to the present invention includes a suction port for sucking fluid, a compression mechanism unit for compressing the fluid sucked from the suction port, a discharge port for discharging the fluid compressed by the compression mechanism unit, A low-pressure container type compressor in which a lubricating oil is provided in the sealed container together with the fluid sucked from the suction port, and the fluid contains 51% of R32 refrigerant or R32 refrigerant. The mixed refrigerant contained above is characterized in that the lubricating oil is an ester oil or an ether oil.

  Since the compressor according to the present invention is a low pressure vessel type in which the ambient temperature of the lubricating oil is low, a low-viscosity grade oil that is difficult to phase separate can be used together with R32 refrigerant or a mixed refrigerant containing 51% or more of R32 refrigerant. The viscosity of the lubricating oil can be secured. Therefore, according to the compressor according to the present invention, it is possible to prevent the refrigerant and the lubricating oil from being separated at a low temperature, and to ensure the lubricity of the sliding portion.

It is a graph explaining the refrigerating machine oil used for the compressor which concerns on Embodiment 1 of this invention, and shows an example of the correlation of the temperature and the viscosity in R32 refrigerant | coolant atmosphere of two types of refrigerating machine oils from which a viscosity grade differs. Yes. It is a graph explaining the refrigerating machine oil used for the compressor concerning Embodiment 1 of the present invention, and shows an example of compatibility with R32 refrigerant and various refrigerating machine oil. It is a graph which expands and shows only the low temperature range of the graph of FIG. 1 is a longitudinal sectional view showing a configuration of a scroll compressor 1 as an example of a compressor according to Embodiment 1 of the present invention.

  Hereinafter, a compressor according to an embodiment of the present invention will be described with reference to the drawings. The configuration, operation, and the like described below are examples, and the compressor according to the present invention is not limited to such configuration, operation, and the like. Moreover, in each figure, the same code | symbol is attached | subjected to the same or similar member or part. Further, the illustration of the fine structure is simplified or omitted as appropriate. In addition, overlapping or similar descriptions are appropriately simplified or omitted.

Embodiment 1 FIG.
[Composition of refrigeration oil]
First, the refrigerating machine oil (lubricating oil) used for the compressor according to Embodiment 1 of the present invention will be described. In the R32 refrigerant atmosphere, the viscosity of the refrigerating machine oil greatly varies depending on the temperature. FIG. 1 is a graph for explaining the refrigerating machine oil used in the compressor according to the present embodiment. Two types of refrigerating machine oils having different viscosity grades (ISO VG) have different temperatures and viscosities (dynamics). An example of the correlation of (viscosity) is shown. The horizontal axis of the graph represents the temperature (° C.) of the refrigerating machine oil, and the vertical axis represents the viscosity (mm ² / s) of the refrigerating machine oil. As shown in FIG. 1, both the viscosity grade 32 refrigerating machine oil and the viscosity grade 68 refrigerating machine oil have a temperature range in which, for example, a viscosity of 5 mm ² / s (indicated by a broken line in the graph of FIG. 1) can be secured. To do. However, the temperature range in which the refrigeration oil is actually used varies depending on whether the compressor is a low pressure container type or a high pressure container type. In the case of a low pressure container type compressor, the ambient temperature range of the refrigerating machine oil (“low pressure container type use area” in FIG. 1) is approximately 10 to 80 ° C., and in the case of a high pressure container type compressor, the atmosphere of the refrigerating machine oil The temperature range (“high pressure vessel type use area” in FIG. 1) is approximately 50 to 120 ° C.

Viscosity grade 32 refrigerating machine oil can secure a viscosity of 5 mm ² / s over the entire temperature range of the low pressure container type, whereas viscosity grade 68 refrigerating machine oil can only be used in a part of the temperature range of the low pressure container type. A viscosity of 5 mm ² / s cannot be ensured. Therefore, in the case of a low pressure container type compressor using R32 refrigerant, viscosity grade 32 is selected as the refrigerating machine oil. Conversely, with a viscosity grade 68 refrigerating machine oil, a viscosity of 5 mm ² / s can be secured over almost the entire temperature range of the high pressure vessel type, whereas with a viscosity grade 32 refrigerating machine oil, the temperature range of the high pressure vessel type is secured. A viscosity of 5 mm ² / s can be ensured only for a part. Therefore, in the case of a high-pressure container type compressor using R32 refrigerant, the viscosity grade 68 is selected as the refrigerating machine oil. This is because when the viscosity grade 32 is used in a high-pressure container type, the viscosity of the oil is halved.

  FIG. 2 is a graph for explaining the refrigerating machine oil used in the compressor according to the present embodiment. The compatibility of the R32 refrigerant and various refrigerating machine oils (correlation between the refrigerating machine oil ratio and the two-phase separation temperature). An example is shown. The horizontal axis of the graph represents the ratio (oil content) (wt%) of the mass of the refrigerating machine oil to the total mass of the refrigerant and the refrigerating machine oil, and the vertical axis represents the temperature (° C.). The curve in the graph indicates the two-phase separation temperature between the R32 refrigerant and various refrigeration oils. In each refrigeration oil, the region above the curve in the graph is a dissolution region where the R32 refrigerant and the refrigeration oil are compatible, and the region below the curve is a two-phase separation between the R32 refrigerant and the refrigeration oil. It becomes a separation area. In FIG. 2, ester oils of viscosity grades 32, 46 and 68 and ether oils of viscosity grades 32 and 68 are shown as various refrigerator oils.

  As shown in FIG. 2, in the R32 refrigerant atmosphere, regardless of the oil content, when the temperature is low, the refrigerant and the oil are not melted and separated into two phases of the refrigerant and the oil. In this regard, the inventors have found that the characteristics of the oil two-phase separation temperature relative to the R32 refrigerant are related to the oil viscosity grade. In the case of ether oil, the viscosity grade 68 type may be separated into two phases at about −2 ° C., but the viscosity grade 32 type does not undergo two-phase separation up to −30 ° C. In the case of ester oil, the viscosity grade 68 type may undergo two-phase separation at about −15 ° C., but the viscosity grade 32 or 46 type does not undergo two-phase separation until −42 ° C. That is, when the viscosity grade is set low, the two-phase separation is less likely to occur at lower temperatures, and the compatibility tends to be ensured up to lower temperatures. Conversely, if the viscosity grade is set high, the two-phase separation tends to occur at a low temperature range.

  In addition, ester oil is less likely to undergo two-phase separation at lower temperatures than ether oil, and compatibility tends to be ensured at lower temperatures. Usually, in the use of home air conditioners, the length of the refrigerant pipe is short, so the working temperature range with a lower limit of about 0 to -5 ° C is acceptable. However, when used in an air conditioner for buildings, the refrigerant pipe Since the length is long, it may be used at about -15 to -20 ° C. Moreover, in the case of the refrigeration refrigerator used for a refrigeration use or a freezing use, there exists a possibility of being used at about -35--40 degreeC.

  Here, the “ether oil” in the present specification indicates a polyvinyl ether particularly suitable for use as a refrigerating machine oil. The “ether oil” having the same characteristics as the “ether oil” and usable as a refrigerating machine oil includes synthetic ether oils such as polyphenyl ether and perfluoroether in addition to polyvinyl ether. In addition, the “ester oil” in the present specification indicates a polyol ester particularly suitable for use as a refrigerating machine oil. “Ester oils” having the same characteristics as “ester oils” and usable as refrigerating machine oils include synthetic ester oils such as monoesters, diesters, and phosphate esters in addition to polyol esters.

  FIG. 3 is an enlarged graph showing only the low temperature region of the graph of FIG. 3, in addition to the curves showing the compatibility between the viscosity grade 32 ether oil and the viscosity grade 32, 46 ester oil and the R32 refrigerant shown in FIG. 2, the viscosity grade 32 ester oil and the R32 refrigerant are 50%. Curves showing compatibility with the contained R410A refrigerant are shown by broken lines. In the R32 refrigerant atmosphere, as described above, ester oil (ester oil) is less likely to be two-phase separated to a lower temperature than ether oil (ether oil), and tends to ensure compatibility to a low temperature. . In the case of a refrigerant circuit using an R410A refrigerant and a viscosity grade 32 ester-based oil, which have become common nowadays, the two-phase separation temperature was approximately -37 ° C.

  That is, the two-phase separation temperature (−42 ° C.) when the R32 refrigerant and the viscosity grade 32 or 46 ester oil are used is the two-phase separation when the R410A refrigerant and the viscosity grade 32 ester oil is used. It becomes lower than the temperature (−37 ° C.). On the other hand, the two-phase separation temperature (−15 ° C.) when the R32 refrigerant and the viscosity grade 68 ester oil are used is the two-phase separation temperature (−15 ° C.) when the R410A refrigerant and the viscosity grade 32 ester oil is used ( -37 ° C). The two-phase separation temperature (−30 ° C. or −2 ° C.) when R32 refrigerant and viscosity grade 32 or 68 ether oil are used is the same as that when R410A refrigerant and viscosity grade 32 ester oil are used. It becomes higher than the two-phase separation temperature (−37 ° C.). Accordingly, in the refrigerant circuit in which the R410A refrigerant and the viscosity grade 32 ester-based oil are used, when the R32 refrigerant (or a mixed refrigerant containing 51% or more of the R32 refrigerant) is used instead of the R410A refrigerant, the viscosity grade 32 is used. If an ester oil of 46 or less is used, the refrigerant circuit can be used as it is.

[Configuration of scroll compressor]
Next, the configuration of the compressor according to the present embodiment will be described. The compressor according to the present embodiment is a low-pressure container type in which lubricating oil is provided in a sealed container together with a refrigerant (an example of a fluid) sucked from an inlet. FIG. 4 is a longitudinal sectional view showing a configuration of the scroll compressor 1 as an example of the compressor according to the present embodiment. As shown in FIG. 4, the scroll compressor 1 has a configuration in which a compression mechanism unit 30 that compresses a refrigerant and an electric motor unit 20 that drives the compression mechanism unit 30 are housed in an airtight container 10. . The sealed container 10 is divided into three parts, a container lower part 10a, a container intermediate part 10b, and a container upper part 10c. An oil sump 11 for storing refrigerating machine oil that lubricates each sliding portion is formed at the bottom of the container lower portion 10a. A suction pipe 12 is connected to the container middle portion 10b as a suction port for sucking low-pressure refrigerant into the sealed container 10. In addition, a frame 33 is fixedly supported at the upper end of the container intermediate portion 10b, and the motor stator 21 of the motor unit 20 is fixedly supported at the lower portion thereof, and the subframe 38 is disposed at the lower end portion thereof. Fixedly supported. A discharge pipe 13 is connected to the container upper part 10 c as a discharge port for discharging the compressed refrigerant to the outside of the sealed container 10.

  The electric motor unit 20 drives the swing scroll 32 of the compression mechanism unit 30 via the main shaft 40 in order to compress the refrigerant gas by the compression mechanism unit 30. The electric motor unit 20 includes an electric motor stator 21 fixed to the inner peripheral surface of the sealed container 10 and an electric motor rotor 22 fixed to the main shaft 40. The electric motor rotor 22 is rotationally driven by energizing the electric motor stator 21, and rotates the main shaft 40 that transmits the driving force to the swing scroll 32. At the upper end of the main shaft 40, an eccentric shaft portion 40a that is rotatably fitted to the rocking bearing 34 of the rocking scroll 32 is formed. Inside the main shaft 40, an oil hole 40 c serving as a flow path for the refrigerating machine oil stored in the oil sump 11 is provided so as to penetrate from the lower end to the upper end of the main shaft 40. In addition, balancers 48 and 49 for balancing the orbiting scroll 32 with respect to the center of rotation of the main shaft 40 are provided at the upper portion of the main shaft 40 and the lower portion of the motor rotor 22, respectively.

  The compression mechanism unit 30 includes a fixed scroll 31 and a swing scroll 32. The fixed scroll 31 is fixed to the frame 33 fixedly supported by the container intermediate portion 10b. The fixed scroll 31 includes an end plate 31a and a wrap portion 31b (an example of a spiral portion) that is an involute-curved spiral protrusion provided upright on one surface (the lower surface in this example) of the end plate 31a. Yes. A discharge port 31 c that discharges the compressed refrigerant gas to a high pressure is formed at the center of the fixed scroll 31.

  The orbiting scroll 32 performs a revolving orbiting motion without rotating with respect to the fixed scroll 31. The orbiting scroll 32 includes an end plate 32a and a wrap portion 32b (an example of a spiral portion) that is a spiral projection having an involute curve that is erected on one surface (upper surface in this example) of the end plate 32a. ing. A thrust plate 42 serving as a thrust bearing is provided on the surface (thrust bearing surface) of the swing scroll 32 opposite to the surface on which the lap portion 32b is formed (the anti-compression chamber side). The thrust bearing surface of the orbiting scroll 32 is supported in the axial direction by the frame 33 via the thrust plate 42. In addition, a bottomed cylindrical rocking bearing 34 is formed at a substantially central portion of the surface of the rocking scroll 32 on the side opposite to the compression chamber. In the swing bearing 34, a slider 46 for supporting the swing scroll 32 is rotatably accommodated in order to make the swing scroll 32 revolve. An eccentric shaft portion 40 a that is a slider mounting shaft provided at the upper end of the main shaft 40 is inserted into the slider 46 so as to be eccentric with respect to the main shaft 40.

  The fixed scroll 31 and the swing scroll 32 are mounted in the sealed container 10 in a state where the wrap portion 31b and the wrap portion 32b whose winding directions are opposite to each other are engaged with each other. By combining the wrap portion 31b of the fixed scroll 31 and the wrap portion 32b of the swing scroll 32, a compression chamber 35 whose volume changes relatively is formed between the wrap portion 31b and the wrap portion 32b. . A seal 43 for preventing refrigerant leakage is provided between the tip of the wrap portion 31b and the upper surface of the end plate 32a. Similarly, a seal 44 for preventing refrigerant leakage is provided between the tip of the wrap portion 32b and the lower surface of the fixed scroll 31. Also, an Oldham ring 36 is disposed between the orbiting scroll 32 and the frame 33 to prevent the orbiting scroll 32 from rotating during the eccentric orbiting motion and to enable the orbiting orbiting motion. . A key portion 36a formed on the upper surface of the Oldham ring 36 is slidably accommodated in an Oldham groove 45 provided in the orbiting scroll 32, and a key portion (not shown) formed on the lower surface is It is slidably accommodated in an Oldham groove (not shown) provided in the frame 33.

  The frame 33 is fixed to the inner peripheral surface of the sealed container 10. The frame 33 fixes and supports the fixed scroll 31 and supports the swing scroll 32 via a thrust plate 42. Further, the frame 33 rotatably supports an upper portion of the main shaft 40 in the vicinity of the eccentric shaft portion 40a via a main bearing 37 provided in the through hole in the center portion. A sleeve 47 for smoothly rotating the main shaft 40 penetrating the main bearing 37 is rotatably accommodated in the main bearing 37.

  The sub frame 38 is provided below the frame 33 and is fixed to the inner peripheral surface of the sealed container 10. The subframe 38 rotatably supports a lower portion of the main shaft 40 through a through hole formed in the center portion. A bearing accommodating portion 38a is provided in the through hole. An outer ring of a ball bearing 39 for rotatably supporting the main shaft 40 is press-fitted and fixed to the bearing housing portion 38a.

  Further, the sub-frame 38 is provided with a positive displacement oil pump 41 for supplying refrigeration oil to each sliding portion. The oil pump 41 is connected to a pump shaft portion 40 b that is provided at the lower end of the main shaft 40 and transmits a rotational force to the oil pump 41. The pump shaft portion 40b is integrally formed with the main shaft 40. An oil hole 40c provided at the center of the main shaft 40 communicates with the oil pump 41 on the lower end side.

  As the refrigerant, an RFC refrigerant (single refrigerant) which is an HFC system having an ozone layer depletion coefficient (ODP) of zero, or a mixed refrigerant containing R32 refrigerant in a mass fraction of 51% or more is used. This mixed refrigerant contains a mass fraction of 49% or less because of an HFC refrigerant (for example, R125, R161, etc.) having an ozone depletion coefficient of zero, and halogenated carbonization having a carbon double bond in the refrigerant composition. Any one or more of hydrogen (for example, HFO-1234yf, HFO-1234ze, HFO-1243zf, etc., which are called Freon-based low GWP refrigerants) and hydrocarbons (for example, propane and propylene which are natural refrigerants).

[Operation of scroll compressor]
Next, the operation of the scroll compressor 1 according to this embodiment will be described. First, the basic operation will be described. When electric power is supplied to the motor stator 21, the main shaft 40 is rotationally driven by the motor rotor 22. When the main shaft 40 is rotationally driven, the eccentric shaft portion 40 a provided at the upper end of the main shaft 40 rotates in the rocking bearing 34 via the slider 46, and the driving force is transmitted to the rocking scroll 32. At this time, one key portion 36a of the Oldham ring 36 and the other key portion (not shown) reciprocate in the Oldham groove 45 of the orbiting scroll 32 and the Oldham groove (not shown) of the frame 33, respectively. As a result, the orbiting scroll 32 performs an orbiting motion while being prevented from rotating. That is, only the swing motion (swirl motion) is transmitted from the eccentric shaft portion 40 a to the swing scroll 32.

  Here, the frame 33 having the main bearing 37 that rotatably supports the main shaft 40 and the sub-frame 38 having the bearing housing portion 38a in which the outer ring of the ball bearing 39 is press-fitted and fixed in the center are respectively placed in the sealed container 10. It is fixed. However, an axial misalignment may occur between the main bearing 37 and the ball bearing 39 due to variations in accuracy when the frame 33 and the sub-frame 38 are fixed and variations in accuracy of individual components. Further, the main shaft 40 may bend. Due to the misalignment and deflection of the shaft, the main shaft 40 and the main bearing 37 and the main shaft 40 and the ball bearing 39 are not necessarily parallel to each other. For this reason, a sleeve 47 is accommodated between the main shaft 40 and the main bearing 37 in order to make the sliding surfaces in the main bearing 37 parallel. When the shaft misalignment between the main bearing 37 and the ball bearing 39 or the deflection of the main shaft 40 occurs as described above, the main shaft 40 is inclined with respect to the main bearing 37. However, the pivot portion 40e provided on the main shaft 40 comes into contact with the inner peripheral surface of the sleeve 47, and the pivot portion 40e absorbs the inclination, so that the outer peripheral surface of the sleeve 47 always slides in parallel with the main bearing 37. It becomes possible to do.

  The orbiting scroll 32 slides within the slidable range of the sliding surface of the slider 46 with respect to the eccentric shaft portion 40a of the main shaft 40 by centrifugal force. The compression chamber 35 is formed when the wrap portion 32 b of the orbiting scroll 32 and the wrap portion 31 b of the fixed scroll 31 come into contact with each other. A load due to the centrifugal force of the orbiting scroll 32 and a radial load generated to compress the refrigerant are applied to the eccentric shaft portion 40a of the main shaft 40. As a result, deflection occurs in the eccentric shaft portion 40a, so that the eccentric shaft portion 40a and the rocking bearing 34 are not necessarily parallel to each other. For this reason, the slider 46 is accommodated between the eccentric shaft portion 40 a and the swing bearing 34 in order to make the sliding surface in the swing bearing 34 parallel. When the deflection of the eccentric shaft portion 40 a occurs as described above, the eccentric shaft portion 40 a is inclined with respect to the rocking bearing 34. However, the pivot portion 40d provided on the eccentric shaft portion 40a contacts the slide surface of the slider 46, and the pivot portion 40d absorbs the inclination, so that the outer peripheral surface of the slider 46 is always parallel to the swing bearing 34. It is possible to slide on the screen.

  Next, the flow of refrigerant and refrigerating machine oil (lubricating oil) will be described. The refrigerant in the refrigerant circuit is sucked into the sealed container 10 from the suction pipe 12 and flows into the compression chamber 35 through the suction port (not shown) of the frame 33. The refrigerating machine oil sucked up from the oil sump 11 by the oil pump 41 is supplied to each sliding portion in the sealed container 10 through the oil hole 40 c in the main shaft 40 and flows into the compression chamber 35.

  As the sliding portion in the sealed container 10, for example, between the end plate 32a of the swing scroll 32 and the thrust plate 42, between the side surface of the wrap portion 31b of the fixed scroll 31 and the side surface of the wrap portion 32b of the swing scroll 32, A seal 44 provided at the tip of the wrap portion 32b of the swing scroll 32 between the seal 43 provided at the tip of the lap portion 31b of the fixed scroll 31 and the end plate 32a (tooth bottom surface between the wrap portions 32b) of the swing scroll 32. Between the key portion 36a provided on the upper surface of the Oldham ring 36 and the Oldham groove 45 provided on the end plate 32a of the orbiting scroll 32. , Between a key portion (not shown) provided on the lower surface of the Oldham ring 36 and an Oldham groove (not shown) provided on the frame 33, Between the outer peripheral surface of the dynamic bearing 34 and the slider 46, between the outer circumferential surface of the main bearing 37 and the sleeve 47, and the like.

  For example, the lubricating oil that lubricates between the end plate 32 a of the rocking scroll 32 and the thrust plate 42 and leaks to the surface on which the wrap portion 32 b of the rocking scroll 32 is formed is compressed together with the refrigerant flowing from the suction port of the frame 33. 35. The lubricating oil that has flowed into the compression chamber 35 is used for lubrication between the side surfaces of the wrap portion 31b and the wrap portion 32b, between the seal 43 and the end plate 32a, between the seal 44 and the end plate 31a, and the like.

  Although these sliding parts become high temperature with sliding, since they are located in the space into which the relatively low-temperature refrigerant sucked into the sealed container 10 flows, they are cooled by the flowing refrigerant. Further, since the suction pipe 12 is provided in the vicinity of the suction port of the frame 33 and the motor stator 21 and the motor rotor 22, the motor stator 21 and the motor are driven by the relatively low-temperature refrigerant sucked from the suction pipe 12. The rotor 22 and the like are cooled. Since the oil sump 11 is also located in the space into which the relatively low-temperature refrigerant flows, the lubricating oil that has lubricated the sliding portions is cooled by the relatively low-temperature refrigerant.

  As a power source for supplying electric power to the motor stator 21, a general commercial power source with a frequency of 50 Hz or 60 Hz may be used, and the drive rotation speed is changed in the range of 600 to 15000 rpm in order to make the refrigerant circulation amount variable. An inverter power supply that can be used may be used.

  The refrigerant and the lubricating oil flowing into the compression chamber 35 move to the center side of the fixed scroll 31 and the swing scroll 32 by the turning motion of the swing scroll 32. At this time, the refrigerant and the lubricating oil are compressed by changing the shape of the compression chamber 35 and reducing the volume. Due to the compressed refrigerant, a load is applied to the fixed scroll 31 and the swing scroll 32 so as to be separated in the axial direction. This load is supported by a thrust bearing constituted by a thrust plate 42 from a surface opposite to the surface on which the wrap portion 32b of the orbiting scroll 32 is formed.

  The refrigerant and the lubricating oil compressed in the compression chamber 35 pass through the discharge port 31c of the fixed scroll 31 and open the discharge valve 50 provided in the fixed scroll 31 by a pressure difference to become a high pressure portion in the sealed container 10. It passes through the discharge space 14 and is discharged from the discharge pipe 13 to the outside of the sealed container 10. The discharged refrigerant and lubricating oil circulate in the refrigerant circuit and return to the suction pipe 12 of the scroll compressor 1.

  As described above, the compressor according to the present embodiment is a low-pressure container type in which the lubricating oil has a low ambient temperature, and therefore, a low-viscosity grade oil that is difficult to phase-separate (an ester oil having a viscosity grade of 32 to 46 or less). The viscosity of the lubricating oil can be secured even when the ether oil) is used together with the R32 refrigerant or the mixed refrigerant containing 51% or more of the R32 refrigerant. Therefore, according to this Embodiment, it can prevent that a refrigerant | coolant and lubricating oil isolate | separate at low temperature, and can ensure the lubricity of sliding parts, such as a bearing. Thereby, the durability of the compressor can be improved.

  Further, in the present embodiment, low viscosity grade oil that is difficult to phase-separate can be used. Therefore, control and additional parts for returning the oil staying in the refrigerant circuit to the compressor are not necessarily required. A circuit configuration can be used. For this reason, according to this Embodiment, the increase in the manufacturing cost of a compressor and another refrigeration cycle component can be suppressed.

  Further, in this embodiment, since the refrigerant and the lubricating oil can be prevented from separating at a low temperature, the compressor of the present embodiment is a refrigeration refrigerator used in a low temperature region or a building with a long refrigerant circuit. It can be applied to an air conditioner.

  Moreover, in this Embodiment, since the mixed refrigerant | coolant containing 51% or more of R32 refrigerant | coolants or R32 refrigerant | coolants can be used, while being able to reduce an environmental load, environmental conservation can be improved. Since the R32 refrigerant is a refrigerant having a large theoretical coefficient of performance, the energy efficiency of the refrigeration cycle can be increased.

  Moreover, in this Embodiment, since low viscosity grade oil can be used, while being able to improve the oil enclosure efficiency at the time of refrigeration cycle production, the oil extraction efficiency at the time of refrigeration cycle disposal can be improved.

  In the compressor of the present embodiment, R32 refrigerant or a mixed refrigerant containing 51% or more of R32 refrigerant and an ester oil having a viscosity grade of 32 or more and 46 or less are used. Thereby, two-phase separation temperature can be made lower than the case where R410A refrigerant and viscosity grade 32 ester oil are used. Therefore, according to the compressor of the present embodiment, it is possible to use the refrigerant circuit in which the R410A refrigerant and the viscosity grade 32 ester oil are used as they are.

Other embodiments.
The present invention is not limited to the above embodiment, and various modifications can be made.
For example, although the scroll compressor has been described as an example in the above embodiment, the present invention can be applied to various hermetic compressors other than the scroll compressor.

  Further, the above embodiments and modifications can be implemented in combination with each other.

  DESCRIPTION OF SYMBOLS 1 Scroll compressor, 10 sealed container, 10a container lower part, 10b container intermediate part, 10c container upper part, 11 oil sump, 12 suction pipe, 13 discharge pipe, 14 discharge space, 20 motor part, 21 motor stator, 22 motor rotor, 30 compression mechanism, 31 fixed scroll, 31a end plate, 31b lap portion, 31c discharge port, 32 swing scroll, 32a end plate, 32b wrap portion, 33 frame, 34 swing bearing, 35 compression chamber, 36 Oldham ring, 36a key Part, 37 main bearing, 38 subframe, 38a bearing housing part, 39 ball bearing, 40 main shaft, 40a eccentric shaft part, 40b pump shaft part, 40c oil hole, 40d, 40e pivot part, 41 oil pump, 42 thrust plate 43, 44 Seal, 45 Oldham groove, 46 Slider, 47 Sleeve, 48, 49 Balancer, 50 Discharge valve.

A compressor according to the present invention includes a suction port for sucking fluid, a compression mechanism unit for compressing the fluid sucked from the suction port, a discharge port for discharging the fluid compressed by the compression mechanism unit, A low-pressure container type compressor in which a lubricating oil is provided in the sealed container together with the fluid sucked from the suction port, and the fluid contains 51% of R32 refrigerant or R32 refrigerant. or a mixed refrigerant containing the lubricating oil, ester oil or ether oil der is, is characterized in that the viscosity grades (ISO VG) is 32 or more 46 or less.

Claims (5)

A sealed container having a suction port for sucking fluid, a compression mechanism portion for compressing the fluid sucked from the suction port, and a discharge port for discharging the fluid compressed by the compression mechanism portion, A compressor of a low-pressure container type in which a lubricating oil is provided together with the fluid sucked from the suction port in a sealed container,
The fluid is an R32 refrigerant or a mixed refrigerant containing 51% or more of an R32 refrigerant,
The compressor is characterized in that the lubricating oil is an ester oil or an ether oil. The compressor according to claim 1, wherein the lubricating oil has a viscosity grade (ISO VG) of 32 or more and 46 or less. The mixed refrigerant is any one of an HFC refrigerant containing R125 or R161, a halogenated hydrocarbon having a carbon double bond containing HFO-1234yf, HFO-1234ze or HFO-1243zf, or a hydrocarbon containing propane or propylene. The compressor according to claim 1 or 2, wherein one or more of them are contained at 49% or less. The compressor according to any one of claims 1 to 3, wherein the compression mechanism portion forms a compression chamber by combining spiral portions whose winding directions are opposite to each other. The compression mechanism is
A fixed scroll and an orbiting scroll each provided with the spiral portions whose winding directions are opposite to each other;
A rocking bearing provided on the anti-compression chamber side of the rocking scroll;
A frame for supporting the thrust bearing surface of the orbiting scroll via a thrust plate;
A main shaft connected to an oil pump for transmitting a driving force to the orbiting scroll, penetrating a main bearing provided at a center portion of the frame, and supplying the lubricating oil to each sliding portion;
A slider rotatably accommodated in the rocking bearing;
The compressor according to claim 4, further comprising: a sleeve rotatably accommodated in the main bearing.

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