Compressors and refrigeration systems

Abstract

To provide a compressor capable of suppressing rapid lowering of an oil level of refrigerating machine oil.SOLUTION: The compressor includes a casing (20), a compression mechanism (30), a drive shaft (40), a motor (50), and a partition member (80). The casing stores refrigerating machine oil. The compression mechanism compresses the refrigerant housed inside the casing. The drive shaft drives the compression mechanism. The motor has a stator (51) and rotates the drive shaft. The partition member is disposed below the motor. The partition member partitions a side close to the motor and a side far from the motor. The refrigerating machine oil mixed with the refrigerant in the casing separates into a first layer (L1) and a second layer (L2) in the stopped state. The second layer is positioned above the first layer. The lower end (H1) of the partition member is located above the upper end (H2) of the first layer.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] It relates to a compressor and a refrigeration device.

Background Art

[0002] Patent Document 1 (Japanese Patent Application Laid-Open No. 2024-13789) discloses a refrigeration device using a scroll compressor. Conventionally, hydrofluorocarbon (HFC) refrigerants have been used in refrigeration devices. However, in recent years, due to the need to comply with F-gas regulations in Europe and for global environmental protection, the adoption of propane ( R-290 ) refrigerants has been progressing.

Summary of the Invention

Problems to be Solved by the Invention

[0003] When replacing the HFC refrigerant with R-290 a refrigerant, the amount of dissolution in the refrigeration oil increases, and depending on the conditions, the oil level of the refrigeration oil may rapidly decrease.

Means for Solving the Problems

[0004] The compressor according to the first aspect has a casing, a compression mechanism, a drive shaft, a motor, and a partition member. The casing stores the refrigeration oil. The compression mechanism compresses the refrigerant housed inside the casing. The drive shaft drives the compression mechanism. The motor has a stator and rotates the drive shaft. The partition member is disposed below the motor. The partition member partitions the side close to the motor and the side far from the motor. The refrigeration oil mixed with the refrigerant in the casing separates into a first layer and a second layer in the stopped state. The second layer is located above the first layer. The lower end of the partition member is located above the upper end of the first layer.

[0005] In this configuration, when the system is stopped, the refrigerant oil mixed with the refrigerant separates into a first layer and a second layer, with the lower end of the partition member positioned above the upper end of the first layer. Therefore, when the system is stopped, the partition member suppresses the oil rising from the first layer. Consequently, a rapid drop in the oil level of the refrigerant oil can be suppressed.

[0006] The compressor in the second view is the compressor in the first view, and the height of the lower end of the partition member is located below the height of the oil level in the second layer.

[0007] The compressor in the third view is the compressor in the first or second view, and the refrigerant oil is an incompatible oil that is incompatible with the refrigerant.

[0008] The compressor of the fourth aspect is the compressor of the third aspect, wherein the refrigeration oil contains one of polyalkylene glycol, polyvinyl ether, or polyol ester.

[0009] The compressor in the fifth aspect is the compressor in the fourth aspect, and the refrigeration oil is monoal type polyalkylene glycol.

[0010] The compressor in the sixth perspective is a compressor in either the first or fifth perspective, wherein the liquid density of the mixture of refrigerant and refrigerant oil, obtained by dividing the mass by the volume, is greater in the first layer than in the second layer.

[0011] The compressor in the seventh perspective is a compressor in either the first or sixth perspective, and the concentration of the refrigerant oil in the first layer is greater than the concentration of the refrigerant oil in the second layer.

[0012] The compressor in the eighth perspective is a compressor from either the first or seventh perspective, and the refrigerant is a natural refrigerant.

[0013] The compressor of the ninth aspect is the compressor of the eighth aspect, wherein the refrigerant is a single refrigerant consisting of hydrocarbons, or a mixed refrigerant containing hydrocarbons.

[0014] The compressor in the tenth perspective is the compressor in the ninth perspective, and the refrigerant is propane.

[0015] The refrigeration system of the 11th aspect comprises a compressor of any of the types of the 10th aspect. [Brief explanation of the drawing]

[0016] [Figure 1] This is a refrigerant circuit diagram showing the configuration of the refrigeration system of this embodiment. [Figure 2] This is a longitudinal cross-sectional view showing the configuration of the compressor. [Figure 3] This is a perspective view of the lower bearing and oil separator. [Figure 4] This is a plan view of the lower bearing and oil separator. [Figure 5] This is a longitudinal cross-sectional view showing the configuration of a compressor in a state where a two-layer separation zone has occurred. [Figure 6] This is a diagram showing the two-layer separation region. [Figure 7] This is another longitudinal cross-sectional view showing the configuration of the compressor when a two-layer separation zone has occurred. [Figure 8] This is a perspective view of the lower bearing and oil separator in a modified example. [Modes for carrying out the invention]

[0017] In the following explanation, expressions indicating direction such as "up" and "down" are used as appropriate, but these represent the directions when the refrigeration unit 100 is installed and in normal use. For example, the up and down direction is the vertical direction. The vertical direction is the direction parallel to the direction of gravity.

[0018] (1) Overall configuration of the refrigeration unit 100 As shown in Figure 1, the refrigeration system 100 has a refrigerant circuit 100a filled with refrigerant. The refrigerant circuit 100a includes a compressor 10, a heat exchanger 3, a pressure reducing mechanism 4, and an evaporator 5. The compressor 10 is a scroll compressor. The pressure reducing mechanism 4 is, for example, an expansion valve. The refrigerant circuit 100a performs a vapor compression type refrigeration cycle.

[0019] The refrigeration device 100 is an air conditioner. The air conditioner may be a dedicated cooling machine, a dedicated heating machine, or an air conditioner that switches between cooling and heating. In this case, the air conditioner has a switching mechanism (e.g., a four-way switching valve) for switching the circulation direction of the refrigerant. The refrigeration device 100 may also be a water heater, a chiller unit, a cooling device for cooling the air inside a storage, etc. The cooling device cools the air inside a refrigerator, a freezer, a container, etc.

[0020] (2) Compressor 10 As shown in FIG. 2, the compressor 10 includes a casing 20, a compression mechanism 30, a drive shaft 40, a motor 50, and a partition member 80.

[0021] (2-1) Casing 20 The casing 20 is formed in a vertically long cylindrical shape and is configured in a sealed dome type. The motor 50 and the compression mechanism 30 are housed in the casing 20.

[0022] An oil reservoir portion 21 is provided at the bottom of the casing 20. Refrigeration oil is stored in the oil reservoir portion 21. An intake pipe 12 is connected to the upper portion of the casing 20. A discharge pipe 13 is connected to the body portion of the casing 20.

[0023] A housing 27 is fixed to the casing 20. The housing 27 is fixed inside the casing 20, for example, by shrink fitting. The housing 27 is disposed above the motor 50. The compression mechanism 30 is disposed above the housing 27. The inflow end of the discharge pipe 13 is located between the motor 50 and the housing 27.

[0024] A recess 53 is formed in the housing 27. The recess 53 is formed by a part of the upper surface of the housing 27 being recessed. An upper bearing 27a is provided below the recess 53.

[0025] The housing 27 is provided with an oil drain passage 27b. The oil drain passage 27b is a passage for draining the lubricating oil that has flowed into the recess 53 to the outside of the housing 27. The upstream end of the oil drain passage 27b is in communication with the recess 53. An oil return member 56 is provided on the downstream side of the oil drain passage 27b.

[0026] The oil return member 56 guides the lubricating oil discharged from the recess 53 toward the drain passage 27b downwards. A guide plate 57 is provided below the oil return member 56.

[0027] The guide plate 57 guides the lubricating oil discharged from the oil return member 56 to the oil return passage 35 of the motor 50. The guide plate 57 is formed from a tapered plate material that narrows in opening width from top to bottom. The lower part of the oil return member 56 is inserted into the upper part of the guide plate 57. The lower part of the guide plate 57 extends through the gap between the casing 20 and the coil section of the motor 50, and through the gap of the oil return passage 35.

[0028] (2-2) Compression mechanism 30 The compression mechanism 30 comprises a fixed scroll 60 and a movable scroll 70. The fixed scroll 60 is fixed to the upper surface of the housing 27. The movable scroll 70 is positioned between the fixed scroll 60 and the housing 27.

[0029] The fixed scroll 60 comprises a fixed end plate 61, a fixed lap 62, and an outer peripheral wall 63. The outer peripheral wall 63 is formed in a substantially cylindrical shape. The outer peripheral wall 63 is erected on the outer edge of the front surface (bottom surface in Figure 2) of the fixed end plate 61.

[0030] The fixed-side wrap 62 is formed in a spiral shape. The fixed-side wrap 62 is erected inside the outer peripheral wall 63 of the fixed-side end plate 61.

[0031] The fixed end plate 61 is located on the outer circumference and is formed continuously with the fixed wrap 62. The tip surface of the fixed wrap 62 and the tip surface of the outer circumference wall 63 are formed to be substantially flush. The fixed scroll 60 is fixed to the housing 27.

[0032] The movable scroll 70 includes a movable end plate 71, a movable lap 72, and a boss portion 73. The movable lap 72 is formed in a spiral shape. The movable lap 72 is formed on the upper surface of the movable end plate 71. The movable lap 72 engages with the fixed lap 62.

[0033] The boss portion 73 is formed in the center of the lower surface of the movable end plate 71. The eccentric portion 42 of the drive shaft 40 is inserted into the boss portion 73, and the drive shaft 40 is connected to it.

[0034] An Oldham joint 45 is provided at the top of the housing 27. The Oldham joint 45 prevents the movable scroll 70 from rotating.

[0035] The compression mechanism 30 has a fluid chamber S into which the refrigerant flows. The fluid chamber S is formed between a fixed scroll 60 and a movable scroll 70. The movable scroll 70 is arranged such that its movable side wrap 72 engages with the fixed side wrap 62 of the fixed scroll 60. Here, the lower surface of the outer peripheral wall 63 of the fixed scroll 60 is the surface facing the movable scroll 70. Also, the upper surface of the movable side end plate 71 of the movable scroll 70 is the surface facing the fixed scroll 60.

[0036] An intake port 64 is formed in the outer peripheral wall 63 of the fixed scroll 60. The intake port 64 opens near the end of the winding of the fixed-side wrap 62. The downstream end of the intake pipe 12 is connected to the intake port 64.

[0037] A discharge port 65 is formed in the center of the fixed end plate 61 of the fixed scroll 60. The discharge port 65 opens on the upper surface of the fixed end plate 61 of the fixed scroll 60. The high-pressure gaseous refrigerant discharged from the discharge port 65 flows out through a passage (not shown) formed in the housing 27 into an upper space 24 that is below the housing 27 and above the motor 50.

[0038] The recess 53 of the housing 27 communicates with the oil supply passage 16 of the drive shaft 40 via the inside of the boss portion 73 of the movable scroll 70. When high-pressure lubricating oil is supplied to the recess 53, a high pressure equivalent to the discharge pressure of the compression mechanism 30 acts upon it. The movable scroll 70 is pressed against the fixed scroll 60 by the high pressure in the recess 53.

[0039] An oil passage 55 is formed inside the housing 27 and the fixed scroll 60. The inlet end of the oil passage 55 communicates with a recess 53 in the housing 27. The outlet end of the oil passage 55 opens to the opposite surface of the fixed scroll 60. The oil passage 55 supplies high-pressure lubricating oil from the recess 53 to the opposing surfaces of the movable end plate 71 of the movable scroll 70 and the outer peripheral wall 63 of the fixed scroll 60.

[0040] (2-3) Drive shaft 40 The drive shaft 40 extends vertically along the central axis of the casing 20. The drive shaft 40 has a main shaft portion 41 and an eccentric portion 42.

[0041] The eccentric portion 42 is provided at the upper end of the main shaft portion 41. The lower part of the main shaft portion 41 is rotatably supported by a lower bearing 22. The lower bearing 22 is fixed to the inner circumferential surface of the casing 20. For example, a positive displacement pump 23 is provided on the lower bearing 22. The upper part of the main shaft portion 41 passes through the housing 27 and is rotatably supported by an upper bearing 27a of the housing 27.

[0042] A balance weight 18 is provided on the drive shaft 40. The balance weight 18 is positioned in the upper space 24 above the rotor 52 of the motor 50.

[0043] An oil supply passage 16 is formed inside the drive shaft 40. The oil supply passage 16 extends vertically from the lower end to the upper end of the drive shaft 40. The lower end of the drive shaft 40 is connected to a pump 23. The lower end of the pump 23 is immersed in an oil reservoir 21. As the drive shaft 40 rotates, the pump 23 draws lubricating oil from the oil reservoir 21 and delivers it to the oil supply passage 16. The oil supply passage 16 supplies the lubricating oil from the oil reservoir 21 to the sliding surfaces of the lower bearing 22 and the drive shaft 40, the sliding surfaces of the upper bearing 27a and the drive shaft 40, and also to the sliding surface of the boss 73 and the drive shaft 40. The oil supply passage 16 opens to the upper end surface of the drive shaft 40 and supplies lubricating oil upward to the drive shaft 40.

[0044] (2-4) Motor 50 The motor 50 includes a stator 51 and a rotor 52.

[0045] The stator 51 is fixed to the inner circumferential surface of the casing 20. Coils 51a are concentrated and wound around teeth (not shown) of the stator 51.

[0046] The rotor 52 is positioned inside the stator 51. The drive shaft 40 passes through the rotor 52. The rotor 52 is fixed to the drive shaft 40. Rotor holes 52a are formed in the rotor 52, penetrating in the axial direction. Multiple rotor holes 52a are formed at intervals in the circumferential direction.

[0047] (2-5) Partition member 80 The partition member 80 is more than the stator 31. Lower space It is positioned there. The partition member 80 divides the space below the stator 51 into a first space 26 and a second space 27. ru.

[0048] 2nd space 27 This is the space furthest from the motor 50. 2nd space 27 This is the space including the oil reservoir 21 at the bottom of the casing 20.

[0049] 1st space 26 This is the space closest to the motor 50. 1st space 26 teeth, 2nd space 27It is located above it. 1st space 26 This is the space into which the refrigerant flows.

[0050] As shown in Figures 3 and 4, the partition member 80 is formed from a ring-shaped plate. The partition member 80 is attached to the lower bearing 22. The mounting position of the partition member 80 to the lower bearing 22 is not particularly limited. For example, the partition member 80 is attached to the lower surface of the lower bearing 22. The outer circumferential surface of the partition member 80 extends to a position where it abuts the inner circumferential surface of the casing 20.

[0051] As shown in Figure 5, the lower end H1 of the partition member 80 is located above the upper end H2 of the first layer L1. The reason for this is as follows.

[0052] This is the space between the motor 50 and the partition member 80. 1st space In 26, the refrigerant swirls as the motor 50 rotates. Due to the effect of this swirling, the refrigerant oil stored in the oil reservoir 21 may be stirred up, rise up inside the casing 20, and leak out, which is known as "oil spillage."

[0053] Furthermore, if the unit is shut down for an extended period in an environment with low ambient temperatures, a large amount of refrigerant dissolves into the refrigeration oil, resulting in a condition known as "stagnation." When the compressor 10 is started in this state, the refrigerant components in the mixture rapidly vaporize, potentially causing foaming. This foaming can lift the refrigeration oil along with the bubbles, potentially leading to discharge from the oil reservoir. If this oil-lifting phenomenon occurs, the amount of lubricating oil may become insufficient, potentially leading to unstable lubrication supply to the sliding parts and bearings of the compressor 10.

[0054] Here, by setting the lower end H1 of the partition member 80 above the upper end H2 of the first layer L1, the path for oil upflow is physically blocked, and the refrigerant oil in the oil reservoir 21 is prevented from being drawn up to the top of the casing 20. As a result, even when stopped, the refrigerant oil remains properly in the oil reservoir 21, and a rapid drop in the oil level can be prevented. The partition member 80 can suppress the discharge of refrigerant oil from the oil reservoir 21.

[0055] On the other hand, the lower end H1 of the partition member 80 is located below the upper end H3 of the second layer L2. Furthermore, the distance between the lower end H1 of the partition member 80 and the upper end H3 of the second layer L2 is greater than the distance between the lower end H1 of the partition member 80 and the upper end H2 of the first layer L1. The reason for this is as follows: The second layer L2 contains more refrigerant than the first layer L1. Therefore, in the second layer L2, a larger amount of refrigerant dissolves into the refrigerant oil when the system is in a "sleeping state". Because the lower end H1 of the partition member 80 is located below the upper end H3 of the second layer L2, bubbles and refrigerant generated by foaming can easily escape upwards, allowing for rapid separation and rearrangement of the refrigerant and oil. As a result, refrigerant oil is properly retained in the oil reservoir 21 even when restarting, ensuring lubrication and enabling stable system operation.

[0056] In this embodiment, by arranging the heights in the order of the upper end H2 of the first layer L1, the lower end H1 of the partition member 80, and the upper end H3 of the second layer L2, the discharge of refrigerant oil is suppressed while not obstructing the flow of the refrigerant, both during shutdown and restart.

[0057] An outlet passage 81 is formed in the partition member 80. The outlet passage 81 allows a mixture of refrigerant oil and R-290, as well as refrigerant oil, to pass through. The outlet passage is formed in the shape of an elongated hole extending in the circumferential direction. Multiple outlet passages are provided at intervals in the circumferential direction.

[0058] A notch 82 is formed in the partition member 80. The notch 82 allows the lubricating oil accumulated on the partition member 80 to fall into the oil reservoir 21.

[0059] (3) Refrigerants and refrigerant oils In this embodiment, the refrigerant used in the compressor 10 is propane. R-290 The refrigerant is not limited to propane, but is a single refrigerant consisting of hydrocarbons or a mixed refrigerant containing hydrocarbons. Hydrocarbons are selected from the group consisting of, for example, propane, butane, and isobutane. The refrigerant may also be a natural refrigerant other than hydrocarbons. Natural refrigerants include, for example, at least one of carbon dioxide, ammonia, and water.

[0060] In this embodiment, the refrigeration oil used in the compressor 10 is a monool-type polyalkylene glycol, which is an incompatible oil. Incompatible oils are incompatible with refrigerants. A monool-type polyalkylene glycol is a polyalkylene glycol having one hydroxyl group at one end. The refrigeration oil is not limited to monool-type polyalkylene glycol, as long as it is an incompatible oil containing polyalkylene glycol, polyvinyl ether, or polyol ester. Hereinafter, the monool-type polyalkylene glycol used as the refrigeration oil in the compressor 10 will be referred to as "PAG oil".

[0061] As shown in Figures 5 and 6, when R-290 is mixed into PAG oil, the mixture separates into two layers, a first layer L1 and a second layer L2, depending on the R-290 being mixed and the temperature conditions. When the compressor 10 is stopped, the mixture separates into two layers, a first layer L1 and a second layer L2. The second layer L2 is located above the first layer L1. In the first layer L1, the PAG oil content is greater than the R-290 content. In the second layer L2, the R-290 content is greater than the PAG oil content. Therefore, the liquid density of the first layer L1 is greater than the liquid density of the second layer L2. Here, liquid density is the mass of the mixture of R-290 and PAG oil divided by its volume.

[0062] The concentration of PAG oil in the first layer L1 is greater than the concentration of PAG oil in the second layer L2. The concentration of PAG oil corresponds to the wt% of PAG oil content in the mixture. Specifically, the concentration of PAG oil is the value obtained by dividing the mass of PAG oil contained in the mixture by the mass of the mixture. The density of PAG oil is greater than the density of propane. Therefore, the density of the mixture in the first layer L1 is greater than the density of the mixture in the second layer L2.

[0063] The volume resistivity of the second layer L2 is 1.0 × 10⁻⁶ 10 The resistivity is greater than or equal to Ω·m. Volume resistivity is a physical property that represents the volume resistance per unit volume of the test material. The lower the volume resistivity, the lower the electrical insulation performance. Volume resistivity is measured at room temperature (25°C) in accordance with IEC60247.

[0064] The upper end H3 of the second layer L2 is, Partition member 80 It is located above the lower end H1. 。

[0065] (4) Operating The basic operation of the compressor 10 will now be explained. In Figure 2, when the motor 50 is activated, the drive shaft 40 to which the rotor 52 is fixed rotates. Also, since the movable scroll 70 is prevented from rotating by the Oldham coupling 45, it rotates around the axis of the drive shaft 40.

[0066] As the movable scroll 70 rotates, the refrigerant is compressed in the fluid chamber S. The high-pressure gaseous refrigerant compressed in the fluid chamber S is discharged from the outlet 65 and flows out into the upper space 24 via a passage (not shown) formed in the housing 27.

[0067] A portion of the refrigerant that flows out into the upper space 24 flows into the motor 50 and flows downward along the inner surface of the casing 20. The refrigerant that flows out of the motor 50 flows towards the upper space 24 through the rotor holes 52a formed in the rotor 52. This flow of refrigerant cools the motor 50.

[0068] The high-pressure gaseous refrigerant flowing through the upper space 24 is discharged to the outside of the casing 20 via the discharge pipe 13.

[0069] As the drive shaft 40 rotates, the high-pressure lubricating oil in the oil reservoir 21 is drawn up by the pump 23 and flows upward through the oil supply passage 16 of the drive shaft 40, and flows out from the opening at the upper end of the eccentric portion 42 of the drive shaft 40.

[0070] The lubricating oil that leaks out from the opening at the upper end of the eccentric portion 42 of the drive shaft 40 flows into the boss portion 73 of the movable scroll 70.

[0071] The lubricating oil supplied to the boss portion 73 flows out into the recess 53 of the housing 27 through the gap between the eccentric portion 42 of the drive shaft 40 and the boss portion 73. As a result, the recess 53 of the housing 27 becomes high pressure, equivalent to the discharge pressure of the compression mechanism 30. The high pressure in the recess 53 presses the movable scroll 70 against the fixed scroll 60.

[0072] The lubricating oil that flows out from the opening at the upper end of the eccentric portion 42 of the drive shaft 40 also spreads to the sliding surface of the Oldham coupling 45, lubricating the Oldham coupling 45. The lubricating oil further lubricates the thrust sliding surfaces on which the fixed scroll 60 and the movable scroll 70 slide.

[0073] After lubricating each part, the lubricating oil is discharged and returned to the oil reservoir 21. The guide plate 57 directs the lubricating oil discharged from the oil return member 56 to the oil return passage 35 of the motor 50.

[0074] (5) Characteristics (5-1) R-290 refrigerant dissolves more readily into refrigerant oil (PAG oil in this embodiment) compared to HFC refrigerants. In particular, when the outside air is cold and the refrigerant stagnates, a so-called "sleep state," the amount of R-290 refrigerant dissolving into the PAG oil increases. Therefore, due to the liquid compression start of the sleep liquid refrigerant (sleep start), the refrigerant components in the mixture vaporize rapidly, and a foaming phenomenon may occur. The foamed PAG oil, along with the R-290, flows through the discharge pipe. 13The oil leaks out of the casing 20 and is discharged as oil uptake. This can cause the PAG oil level to drop rapidly, potentially impairing the lubrication of the compressor 10.

[0075] Furthermore, the space between the motor 50 and the partition member 80 1st space In section 26, the R-290 rotates in conjunction with the rotation of the motor 50. This rotation causes the PAG oil in the oil reservoir 21 to be stirred up. This stirring also contributes to oil leakage, potentially leading to the discharge of PAG oil.

[0076] In this embodiment, when the compressor 10 is stopped, the mixture separates into two layers: a first layer L1 and a second layer L2. The second layer L2 is located above the first layer L1. The lower end H1 of the partition member 80 is above the first layer L1 It is positioned above the upper end H2. Therefore, the partition member 80 can suppress the stirring up of PAG oil from the oil reservoir 21. As a result, the partition member 80 can suppress the discharge of PAG oil from the oil reservoir 21.

[0077] Furthermore, even if rapid foaming occurs during startup, the mixed liquid is returned to the oil reservoir 21 by the partition member 80. Therefore, a rapid drop in the PAG oil level can be suppressed.

[0078] (5-2) The second layer L2 contains more R-290 than PAG oil. Therefore, in the second layer L2, when the system is simmering, a large amount of R-290 dissolves into the PAG oil. When the compressor 10 is started in this state, the dissolved R-290 rapidly vaporizes, which can cause foaming. In such cases of foaming, it is necessary to quickly recirculate the R-290 into the refrigerant circuit 100a.

[0079] In this embodiment, the height H1 of the lower end of the partition member 80 is located below the height H3 of the oil level in the second layer L2. Therefore, the partition member 80 does not physically obstruct the upward flow of R-290, and promotes the flow of R-290. As a result, the R-290 that has risen due to foaming is quickly discharged to the outside of the casing 20, making it easier to quickly resolve the stagnation (stagnation) of R-290.

[0080] In this embodiment, by arranging the heights in the order of the upper end H2 of the first layer L1, the lower end H1 of the partition member 80, and the upper end H3 of the second layer L2, it is possible to suppress the discharge of PAG oil while promoting the recirculation of R-290 into the refrigerant circuit 100a.

[0081] (5-3) Refrigerant oil is an incompatible oil that is incompatible with the refrigerant. In this case, when R-290 is mixed with refrigerant oil, the mixture separates into a first layer L1 and a second layer L2 when the compressor 10 is stopped.

[0082] (5-4) The refrigeration oil contains one of the following: polyalkylene glycol, polyvinyl ether, or polyol ester. In this case, when R-290 is mixed with the refrigeration oil, the mixture separates into a first layer L1 and a second layer L2 when the compressor 10 is stopped.

[0083] (5-5) The refrigeration oil is a monoal type polyalkylene glycol. In this case, when R-290 is mixed with the refrigeration oil, the mixture separates into a first layer L1 and a second layer L2 when the compressor 10 is stopped.

[0084] (5-6) The liquid density of the first layer is greater than that of the second layer. Liquid density is the mass of the refrigerant and refrigerant oil mixture divided by its volume.

[0085] (5-7) The concentration of the refrigerant oil in the first layer is greater than the concentration of the refrigerant oil in the second layer.

[0086] (5-8) The refrigerant is a natural refrigerant.

[0087] (5-9) The refrigerant is a single refrigerant consisting of hydrocarbons, or a mixed refrigerant containing hydrocarbons.

[0088] (5-10) The refrigerant is propane.

[0089] (6) Variant (6-1) Variation A In the above embodiment, the partition member 80 was a ring-shaped plate, but it is not limited to this. The partition member 80 may be, for example, a mesh.

[0090] (6-2) Variation B In the above embodiment, the partition member 80 is attached to the lower bearing 22, but is not limited to this. The partition member 80 may be attached to the body, for example.

[0091] (6-3) Modification C In the above embodiment, the upper end H3 of the second layer L2 is Partition member 80 It is located above the lower end H1, but is not limited to this. The upper end H3 of the second layer L2 is, for example, as shown in Figure 7. Partition member 80 It may be positioned below the lower end H1.

[0092] (6-4) Modification D The partition member 80 may have a three-dimensional shape, for example, as shown in Figure 8. In this case, the partition member 80 has a flat portion 83 and a wall portion 84. The flat portion 83 is an annular plate. The wall portion 84 is integrally provided with the flat portion 83. The wall portion 84 is an annular shape extending upward from the inner circumference of the flat portion 83. The upper end of the wall portion 84 is positioned to fit into the inner circumference of the coil 51a of the stator 51. The outer diameter of the wall portion 84 is larger than the inner diameter of the stator 51.

[0093] In modification D, the lower end H1 of the partition member 80 is the lower end of the flat portion 83.

[0094] (6-5) Modification E In the above embodiment, the outer circumferential surface of the partition member 80 extends to a position where it contacts the inner circumferential surface of the casing 20, but the embodiment is not limited to this form. For example, a small gap may be provided between the outer circumferential surface of the partition member 80 and the inner circumferential surface of the casing 20, taking into consideration dimensional tolerances of the partition member 80 and ease of assembly.

[0095] (6-6) Modification F In the above embodiment, only PAG oil was used as the refrigeration oil, but it is not limited to this. The refrigeration oil may be a mixture of PAG oil and other oils. For example, the refrigeration oil may be a mixture of PAG oil and polyoxyethylene (POE) oil. In this case, the POE oil content is preferably 40 to 80% by mass.

[0096] While embodiments of this disclosure have been described above, it should be understood that various modifications to the form and details are possible without departing from the spirit and scope of this disclosure as described in the claims. [Industrial applicability]

[0097] As described above, this disclosure is useful for compressors and refrigeration equipment. [Explanation of Symbols]

[0098] 10: Compressor 20: Casing 30: Compression mechanism 40: Drive shaft 50: Motor 51: Status 80: Partition member 100: Refrigeration equipment 100a: Refrigerant circuit L1: 1st layer L2: 2nd layer [Prior art documents] [Patent Documents]

[0099] [Patent Document 1] Japanese Patent Publication No. 2024-13789

Claims

1. A casing (20) for storing refrigerant oil, A compression mechanism (30) for compressing the refrigerant contained inside the casing, A drive shaft (40) that drives the compression mechanism, A motor (50) having a stator (51) and rotating the drive shaft, A partition member (80) is positioned below the motor and separates the side closer to the motor from the side further away from the motor. Equipped with, The refrigerant oil mixed with the refrigerant within the casing separates into a first layer (L1) and a second layer (L2) located above the first layer when the system is stopped. The concentration of the refrigerant oil in the first layer is greater than the concentration of the refrigerant oil in the second layer. The lower end (H1) of the partition member is located above the upper end (H2) of the first layer. The height of the lower end of the partition member is located below the height of the oil level in the second layer. Compressor.

2. The refrigeration oil is an incompatible oil that is incompatible with the refrigerant. The compressor according to claim 1.

3. The aforementioned refrigeration oil contains polyalkylene glycol, polyvinyl ether, and polyol ether. Includes any of the following: The compressor according to claim 2.

4. The aforementioned refrigeration oil is a monoal type polyalkylene glycol. The compressor according to claim 3.

5. Regarding the liquid density obtained by dividing the mass of the mixture of the refrigerant and the refrigerant oil by its volume, the first layer The liquid density of the first layer is greater than the liquid density of the second layer. A compressor according to any one of claims 1 to 4.

6. The aforementioned refrigerant is a natural refrigerant. A compressor according to any one of claims 1 to 4.

7. The refrigerant is a single refrigerant consisting of hydrocarbons, or a mixed refrigerant containing hydrocarbons. The compressor according to claim 6.

8. The refrigerant is propane. The compressor according to claim 7.

9. A refrigeration apparatus comprising the compressor described in any one of claims 1 to 4.

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