The present disclosure relates to a scroll compressor including an oil separation member that separates refrigerant from oil.
A scroll compressor disclosed in JP 2015-105637 A includes an oil separation plate. The oil separation plate suppresses scattering of lubricating oil that can be caused by a refrigerant gas contacting an oil reservoir. The oil separation plate is fixed to a lower bearing member. The lower bearing member has three legs. The three legs are fixed to an inner peripheral face of a casing.
A refrigerant discharged from a compression mechanism contains the lubricating oil. The refrigerant then moves to near the lower bearing member. There, the refrigerant receives a force from a rotating rotor and swirls in a circumferential direction of the casing along the oil separation plate. As the refrigerant swirls, the lubricating oil is separated from the refrigerant by cyclone separation.
A scroll compressor according to a first aspect includes a casing, a scroll compression mechanism disposed in the casing, a motor disposed in the casing below the scroll compression mechanism, a crankshaft connecting the scroll compression mechanism and the motor, a bearing disposed below the motor, a frame fixed to the casing; and an oil separation member fixed to the frame. The motor includes a stator and a rotor rotatable in a rotational direction. The bearing rotatably supports the crankshaft. The oil separation member is configured to suppress mixing of a refrigerant and a lubricating oil in the casing. The frame supports the bearing. The frame has a first fixed leg fixed to the casing and a second fixed leg fixed to the casing. The oil separation member has a first horizontal surface and a first inclined surface. The first inclined surface has a first inclined surface upstream portion and a first inclined surface downstream portion in the rotational direction. The first inclined surface downstream portion is disposed higher than the first inclined surface upstream portion. The first horizontal surface, the first inclined surface, and the first fixed leg are disposed in order from upstream to downstream in the rotational direction.
In this configuration, a swirling flow of the refrigerant advances obliquely upward by the first inclined surface, and then approaches the first fixed leg. Therefore, the swirling flow of the refrigerant is prevented from colliding with first fixed leg.
(1) Overall Configuration
(2) Detailed Configurations
(2-1) Casing 11
As illustrated in
(2-2) Motor 20
The motor 20 generates power for driving the scroll compression mechanism 40. The motor 20 is disposed in the casing 11. The motor 20 is disposed below the scroll compression mechanism 40. The motor 20 includes a stator 21 and a rotor 22.
The stator 21 includes coils (not illustrated). The coils convert power received by the scroll compressor 10 into magnetic force. The stator 21 has a substantially cylindrical shape. The stator 21 is fixed to the barrel 11a. The stator 21 has on its outer periphery a notch called a core cut 21a. A gap formed by the core cut 21a between the barrel 11a and the stator 21 functions as a passage for the refrigerant.
The rotor 22 is disposed near the stator 21. The rotor 22 includes a permanent magnet (not illustrated). The rotor 22 has a substantially cylindrical shape. The coils of the stator 21 and the permanent magnet of the rotor 22 interact with each other to rotate the rotor 22.
(2-3) Crankshaft 30
The crankshaft 30 transmits power generated by the motor 20 to the scroll compression mechanism 40. The crankshaft 30 connects the scroll compression mechanism 40 and the motor 20. The crankshaft 30 is fixed to the rotor 22. The crankshaft 30 has a concentric portion 31 and an eccentric portion 32. The concentric portion 31 is concentric with an axis of the rotor 22 and the crankshaft 30. The eccentric portion 32 is eccentric from the axis. The concentric portion 31 is rotatably supported by an upper bearing 35 and a lower bearing 36. The eccentric portion 32 is rotatably supported by an eccentric bearing 37. The upper bearing 35 is disposed above the motor 20. The lower bearing 36 is disposed below the motor 20. The eccentric bearing 37 is disposed near the scroll compression mechanism 40.
An oil ascending hole 33 is provided inside the crankshaft 30. As the crankshaft 30 rotates, the lubricating oil in the oil reservoir 12 is sucked up into the oil ascending hole 33 and then supplied to the scroll compression mechanism 40, the upper bearing 35, the lower bearing 36, and the eccentric bearing 37.
(2-4) Scroll Compression Mechanism 40
The scroll compression mechanism 40 is disposed in the casing 11. The scroll compression mechanism 40 includes a fixed scroll 41 and a movable scroll 42.
The fixed scroll 41 includes a fixed plate 41a and a fixed wrap 41b. The fixed plate 41a is a part extending in a horizontal direction. The fixed wrap 41b extends in a vertical direction from the fixed plate 41a. The fixed wrap 41b has a spiral shape in plan view. A discharge hole 45 for discharging a high-pressure refrigerant is formed at a center of the fixed plate 41a.
The movable scroll 42 includes a movable plate 42a, a movable wrap 42b, and a movable protrusion 42c, The movable plate 42a is a part extending in the horizontal direction. The movable wrap 42b extends in the vertical direction from the movable plate 42a. The movable wrap 42b has a spiral shape in plan view. The movable protrusion 42c extends in the vertical direction from the movable plate 42a. The movable protrusion 42c has a concave portion. The concave portion accommodates the eccentric bearing 37 and the eccentric portion 32. The movable scroll 42 can revolve around the fixed scroll 41.
The fixed scroll 41 and the movable scroll 42 together define a plurality of compression chambers 43. The compression chamber 43 at an outermost position communicates with the suction pipe 15.
(2-5) Upper Frame 50
The upper frame 50 supports the upper bearing 35. The upper frame 50 supports the crankshaft 30 via the upper bearing 35. The upper frame 50 is fixed to the barrel 11a of the casing 11. The fixed scroll 41 is fixed to the upper frame 50. The upper frame 50 is provided with a refrigerant passage 50a vertically penetrating the upper frame 50.
(2-6) Lower Frame 60
The lower frame 60 supports the lower bearing 36. The lower frame 60 supports the crankshaft 30 via the lower bearing 36. The lower frame 60 is fixed to the barrel 11a of the casing 11.
(2-7) Oil Separation Member 70
The oil separation member 70 suppresses mixing of the refrigerant and the lubricating oil. That is, the oil separation member 70 suppresses scattering of the lubricating oil that may be caused by the gas refrigerant contacting the oil reservoir 12, and thus suppresses mixing of the refrigerant and the lubricating oil. The oil separation member 70 is fixed to the lower frame 60.
(2-8) Oil Guide 51
(2-9) Refrigerant Guide 52
(3) Movements of Refrigerant and Lubricating Oil
Movements of the refrigerant and the lubricating oil will be described below. It should be noted that the refrigerant and the lubricating oil do not move completely independently of each other. The refrigerant and the lubricating oil exhibit compatibility. Thus, the movement of the refrigerant or the lubricating oil discussed below may also be movement of a mixture of the refrigerant and lubricating oil.
(3-1) Refrigerant
The low-pressure refrigerant enters the scroll compressor 10 from the suction pipe 15 illustrated in
The refrigerant guide 52 allows part of the refrigerant to swirl along an inner periphery of the barrel 11a while advancing in the horizontal direction. This swirling flow may be further accelerated by the rotation of the rotor 22. Another part of the refrigerant advances downward, passes through the core cut 21a, and collides with the oil separation member 70. Next, in a lower space S3 between the motor 20 and the lower frame 60, the rotation of the rotor 22 swirls the refrigerant.
(3-2) Lubricating Oil
The lubricating oil is sucked up from the oil reservoir 12 to the oil ascending hole 33. Thereafter, the lubricating oil is supplied to the scroll compression mechanism 40, the upper bearing 35, the lower bearing 36, and the eccentric bearing 37. Subsequently, the lubricating oil exits the scroll compression mechanism 40, the upper bearing 35, the lower bearing 36, and the eccentric bearing 37. Next, the lubricating oil moves downward along the inner peripheral surface of the barrel 11a or the oil return passage P of the oil guide 51. The lubricating oil having exited the oil return passage P falls from the core cut 21a to the oil return passage portion 79 of the oil separation member 70.
(4) Detailed Structure of Lower Frame 60 and Oil Separation Member 70
The lower frame 60 includes a first fixed leg 61, a second fixed leg 62, and a third fixed leg 63. The first fixed leg 61, the second fixed leg 62, and the third fixed leg 63 are all fixed to the barrel 11a of the casing 11. A method of fixing is, for example, welding. The first fixed leg 61 has a first fixed leg upper surface 61a.
The oil separation member 70 is a plate-shaped member fixed to the lower frame 60. A first horizontal surface 71, a second horizontal surface 73, a third horizontal surface 74, a fourth horizontal surface 81, a fifth horizontal surface 83, a sixth horizontal surface 84, a seventh horizontal surface 86, an eighth horizontal surface 88, a first inclined surface 72, a second inclined surface 75, a third inclined surface 82, a fourth inclined surface 85, a fifth inclined surface 87, and a notch 76 are formed at a position close to an outer periphery of the oil separation member 70. The notch 76 allows the lubricating oil accumulated on the oil separation member 70 to fall into the oil reservoir 12.
The first horizontal surface 71, the first inclined surface 72, the second horizontal surface 73, the first fixed leg 61, and the second inclined surface 75 are disposed in that order from upstream to downstream in the rotational direction R. The third horizontal surface 74 and the second fixed leg 62 are disposed in that order from upstream to downstream in the rotational direction R.
The first inclined surface upstream portion 72a and the first inclined surface downstream portion 72b are separated from each other by a first height difference H1. The first inclined surface upstream portion 72a and the first inclined surface downstream portion 72b are separated from each other in the circumferential direction by a first circumferential distance L1. The second horizontal surface 73 and the first fixed leg upper surface 61a are separated from each other by a second height difference H2. The second horizontal surface 73 extends in the circumferential direction by a second circumferential distance L2.
A ratio of the first height difference H1 to the first circumferential distance L1 is a first inclination H1/L1. A ratio of the second height difference H2 to the second circumferential distance L2 is a second inclination H2/L2. The first inclination H1/L1 is larger than the second inclination H2/L2. The first inclination H1/L1 is 0.5 or more and 2.0 or less. The second inclination H2/L2 is 0.3 or more and 1.0 or less.
Returning to
The circumferential distance L2 of the second horizontal surface 73 is set to be larger than the circumferential distance of the fifth horizontal surface 83. This is because the first horizontal surface 71 located upstream of the second horizontal surface 73 is located below the refrigerant guide 52. The first horizontal surface 71 receives a strong refrigerant flow blown downward from the refrigerant guide 52.
(5) Characteristics
In a general compressor without the structure according to the above-mentioned embodiment, the refrigerant swirling in the circumferential direction of the casing along the oil separation plate may contact the legs of the lower bearing member. At this time, swirling of the refrigerant is stopped, and separation of the lubricating oil from the refrigerant is inhibited in this case, a phenomenon called “oil loss” occurs more significantly in which the refrigerant is discharged to outside of the scroll compressor while containing the lubricating oil. As a result, an amount of the lubricating oil in the scroll compressor may be insufficient.
(5-1)
According to the above-mentioned embodiment, the swirling flow of the refrigerant in the lower space S3 advances obliquely upward by the first inclined surface 72, and then approaches the first fixed leg 61. Therefore, the swirling flow of the refrigerant is prevented from colliding with the first fixed leg 61. As a result, since cyclone separation of the swirling flow is less likely to be inhibited, the lubricating oil contained in the refrigerant is likely to be separated from the refrigerant. The separated lubricating oil can return to the oil reservoir 12.
(5-2)
The oil separation member 70 has the third horizontal surface 74. Therefore, the oil separation member 70 can be more easily manufactured than in a case where an inclined surface is formed at a place where the third horizontal surface 74 is to be provided.
(5-3)
The refrigerant swirling along the third horizontal surface 74 in the lower space S3 collides with the second fixed leg 62. Therefore, since the lubricating oil falling into the oil return passage portion 79 is blocked by the second fixed leg 62, the lubricating oil passes through the notch 76 and appropriately falls into the oil reservoir 12.
(5-4)
The oil return passage P includes the core cut 21a. Therefore, a dedicated member constituting the oil return passage P is not required at a height of the motor 20.
(5-5)
The first inclination H1/L1 is larger than the second inclination H2/L2. Therefore, since an advancing direction of the refrigerant flow is set obliquely upward by the first inclined surface 72, the refrigerant flow can be prevented from colliding with the first fixed leg 61.
(5-6)
The second inclined surface 75 having an inclination opposite to an inclination of the first inclined surface 72 is provided downstream of the first fixed leg 61. Therefore, a structure of the oil separation member 70 can be simplified.
(5-7)
The oil separation member 70 has the third inclined surface 78 which is an inclination in the radial direction. Therefore, a level difference formed by the first horizontal surface 71 and the second horizontal surface 73 is absorbed by the third inclined surface 78.
(6) Modifications
The following are modifications of the basic embodiment. For example, a plurality of modifications may be combined.
(6-1) Modification A
This configuration also prevents the swirling flow of the refrigerant in the lower space S3 from colliding with the first fixed leg 61, the second fixed leg 62, and the third fixed leg 63.
(6-2) Modification B
In the basic embodiment, the lower frame 60 has three fixed legs. Alternatively, the number of fixed legs included in the lower frame 60 may be a number other than 3, such as 2, 4, 5, or 6.
The embodiment of the present disclosure has been described above, but it will be understood that various changes to forms and details can be made without departing from the gist and scope of the present disclosure as set forth in the claims.
Number | Date | Country | Kind |
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JP2020-015238 | Jan 2020 | JP | national |
This is a continuation of International Application No. PCT/JP2021/002573 filed on Jan. 26, 2021, which claims priority to Japanese Patent Application No. 2020-015238, filed on Jan. 31, 2020. The entire disclosures of these applications are incorporated by reference herein.
Number | Name | Date | Kind |
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4621993 | Nakamura | Nov 1986 | A |
20130052069 | Iitsuka | Feb 2013 | A1 |
Number | Date | Country |
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101936292 | Jan 2011 | CN |
202441599 | Sep 2012 | CN |
106922163 | Jul 2017 | CN |
3-47496 | Feb 1991 | JP |
4-72998 | Nov 1992 | JP |
2012-202253 | Oct 2012 | JP |
2012202253 | Oct 2012 | JP |
2013047481 | Mar 2013 | JP |
2015-105637 | Jun 2015 | JP |
2015105638 | Jun 2015 | JP |
Entry |
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English Machine Translation of JP2012-202253A (Year: 2012). |
International Preliminary Report of corresponding PCT Application No. PCT/JP2021/002573 dated Aug. 11, 2022. |
International Search Report of corresponding PCT Application No. PCT/JP2021/002573 dated Apr. 6, 2021. |
European Search Report of corresponding EP Application No. 21 74 7932.8 dated Apr. 24, 2023. |
Number | Date | Country | |
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20220316479 A1 | Oct 2022 | US |
Number | Date | Country | |
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Parent | PCT/JP2021/002573 | Jan 2021 | US |
Child | 17845574 | US |