WO2021020346A1

WO2021020346A1 - Compressor

Info

Publication number: WO2021020346A1
Application number: PCT/JP2020/028707
Authority: WO
Inventors: 隆司東田; 里　和哉; 努昆; 昭徳福田
Original assignee: パナソニックＩｐマネジメント株式会社
Priority date: 2019-07-29
Filing date: 2020-07-27
Publication date: 2021-02-04
Also published as: JP2021021363A; JP7369934B2

Abstract

Provided is a compressor in which: a balance weight 90 is disposed above an electric motor portion 30 and below a compressor mechanism portion 20; the balance weight 90 is fixed to a drive shaft 40 by means of a linking portion 91; an oil reservoir portion 15 is formed in an inner bottom portion 14 of a hermetically sealed container 10; an oil feed passage 42 for guiding lubricating oil stored in the oil reservoir portion 15 to the compressor mechanism portion 20 and to a bearing 61, and a communicating hole 44 which communicates with the oil feed passage 42 are formed in the drive shaft 40; the communicating hole 44 is positioned below the balance weight 90; the lubricating oil guided from the oil feed passage 42 is discharged from the communicating hole 44; and by causing a lower end surface 90d of the balance weight 90 to protrude below a lower end 91d of the linking portion 91 of the balance weight 90, so as to approach the electric motor portion 30, contamination of a refrigerant by the lubricating oil discharged from the communicating hole 44 can be reduced.

Description

Compressor

The present invention relates to a compressor used in an outdoor unit of an air conditioner or a refrigerator.

Conventionally, a closed compressor used in a cooling device or a hot water supply device compresses the refrigerant gas returned from the refrigeration cycle by a compression mechanism and sends it to the refrigeration cycle. At that time, lubricating oil is applied to the compression mechanism. It is supplied to lubricate the sliding portion, and the lubricated oil is discharged to the inside of the compressor and returned to the oil reservoir at the bottom of the compressor.
At this time, since the refrigerant gas is in a turbulent flow state inside the closed compressor, a large amount of lubricating oil is mixed with the refrigerant, and the amount of oil discharged to the refrigeration cycle together with the compressed refrigerant is large. It ends up.
Therefore, Patent Document 1 includes a first seal member provided between the balance weight and the swivel scroll and a second seal member provided between the balance weight and the frame, thereby causing an excess inside the compressor. It suppresses the supply of oil.

JP-A-2018-17211

In Patent Document 1, since the gap between the balance weight press-fitted and fixed to the crankshaft and the parts formed above and below the balance weight is sealed with a sealing material, the sealing material is worn or broken due to contact between the rotating body and the sealing material. It is difficult to ensure reliability because of the risk of such problems. In addition, since the number of parts increases, it leads to an increase in assembly man-hours and costs.

Therefore, the present invention provides a compressor that can reduce the mixing of lubricating oil discharged from the communication holes with the refrigerant by bringing the lower end surface of the balance weight closer to the electric motor portion without using a separate member such as a sealing material. The purpose is to do.

The compressor of the present invention according to claim 1 includes a compression mechanism unit 20 and an electric motor unit 30 in a closed container 10, the compression mechanism unit 20 is arranged above the electric motor unit 30, and the compression mechanism unit 20 is provided. And the electric motor unit 30 are connected by a drive shaft 40, a balance weight 90 is arranged above the electric motor unit 30 and below the compression mechanism unit 20, and the balance weight 90 is connected to the drive shaft 40 by the connecting unit 91. An oil reservoir 15 is formed in the inner bottom portion 14 of the closed container 10 so as to be fixed, and the lubricating oil stored in the oil reservoir 15 is guided to the compression mechanism portion 20 and the bearing 61 on the drive shaft 40. The oil supply passage 42 and the communication hole 44 communicating with the oil supply passage 42 are formed, the communication hole 44 is located below the balance weight 90, and the lubricating oil guided from the oil supply passage 42 is the communication hole. A compressor that discharges from 44, characterized in that the lower end surface 90d of the balance weight 90 is projected downward from the lower end 91d of the connecting portion 91 of the balance weight 90.
According to the second aspect of the present invention, in the compressor according to the first aspect, the electric motor unit 30 is fixed to the annular stator 31 and the drive shaft 40 and rotatably arranged inside the stator 31. It is composed of a rotor 32, and the gap dimension S between the lower end surface 90d of the balance weight 90 and the rotor 32 is made smaller than the diameter D of the communication hole 44.
The present invention according to claim 3 is characterized in that, in the compressor according to claim 2, the gap dimension S is 20% or more and 60% or less of the diameter D of the communication hole 44.
The compressor of the present invention according to claim 4 is the compressor according to claim 2 or 3, wherein the gap dimension S is 1 mm or more and 2.7 mm or less.
The compressor of the present invention according to claim 5 is the compressor according to any one of claims 1 to 4, wherein the inside of the closed container 10 is divided into upper and lower partitions. 50 is provided, and the inside of the closed container 10 is compressed by the partition plate 50 with a high-pressure space 16 filled with a high-pressure refrigerant after being compressed by the compression mechanism unit 20 and the compression mechanism unit 20. The low-pressure space 17 is divided into a low-pressure space 17 filled with the low-pressure refrigerant, and the electric motor unit 30, the compression mechanism unit 20, and the balance weight 90 are arranged in the low-pressure space 17, and the low-pressure space 17 is located. The refrigerant is compressed by the compression mechanism unit 20.

According to the present invention, since the lower end surface of the balance weight can be brought close to the electric motor portion, it is possible to reduce the mixing of the lubricating oil discharged from the communication hole with the refrigerant and reduce the amount of oil discharged from the closed container. ..

Side sectional view of the compressor according to an embodiment of the present invention. Enlarged sectional view of the main part of the compressor

In the compressor according to the first embodiment of the present invention, the lower end surface of the balance weight is projected below the lower end of the connecting portion of the balance weight. According to the present embodiment, since the lower end surface of the balance weight can be brought close to the electric motor portion, it is possible to reduce the mixing of the lubricating oil discharged from the communication hole with the refrigerant, and the lubricating oil is mixed with the refrigerant and compressed. The amount of oil discharged from the closed container that flows out into the refrigeration cycle together with the refrigerant can be reduced.

In the compressor according to the first embodiment, the second embodiment of the present invention comprises an annular stator and a rotor fixed to a drive shaft and rotatably arranged inside the stator. The gap between the lower end surface of the balance weight and the rotor is made smaller than the diameter of the communication hole. According to the present embodiment, since the lubricating oil discharged from the communication hole is less likely to come out from the rotor, it is possible to reduce the mixing of the lubricating oil with the refrigerant, and the lubricating oil is mixed with the refrigerant and frozen together with the compressed refrigerant. The amount of oil discharged from the closed container that flows out into the cycle can be reduced.

The third embodiment of the present invention is the compressor according to the second embodiment in which the gap size is 20% or more and 60% or less of the diameter of the communication hole. According to the present embodiment, since the lubricating oil discharged from the communication hole is less likely to come out from the rotor, it is possible to reduce the mixing of the lubricating oil with the refrigerant, and the lubricating oil is mixed with the refrigerant and frozen together with the compressed refrigerant. The amount of oil discharged from the closed container that flows out into the cycle can be reduced.

The fourth embodiment of the present invention has a gap size of 1 mm or more and 2.7 mm or less in the compressor according to the second or third embodiment. According to the present embodiment, since the lubricating oil discharged from the communication hole is less likely to come out from the rotor, it is possible to reduce the mixing of the lubricating oil with the refrigerant, and the lubricating oil is mixed with the refrigerant and frozen together with the compressed refrigerant. The amount of oil discharged from the closed container that flows out into the cycle can be reduced.

In the fifth embodiment of the present invention, in the compressor according to any one of the first to fourth embodiments, a partition plate for partitioning the inside of the closed container is provided in the closed container, and the partition plate is used. The inside of the closed container is divided into a high-pressure space filled with a high-pressure refrigerant after being compressed by the compression mechanism and a low-pressure space filled with a low-pressure refrigerant before being compressed by the compression mechanism. , The electric motor unit, the compression mechanism unit, and the balance weight are arranged, and the refrigerant in the low pressure space is compressed by the compression mechanism unit. When the electric motor unit, compression mechanism unit, and balance weight are arranged in the low-pressure space, the lubricating oil discharged from the communication hole is mixed with the refrigerant in the low-pressure space, so that the lubricating oil mixed in the refrigerant in the low-pressure space is mixed. , It is easy to be discharged together with the high-pressure refrigerant discharged from the compression mechanism unit, but according to this embodiment, since it is possible to reduce the mixing with the refrigerant in the low-pressure space, it is mixed with the refrigerant and the refrigeration cycle is performed together with the compressed refrigerant. The amount of oil discharged from the closed container that flows out to the air can be reduced.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a side sectional view of the compressor according to the present embodiment. In this embodiment, a scroll compressor is used as the compressor.

The closed container 10 has a cylindrical body shell 11 having an axis in the vertical direction, a bowl-shaped lower shell 12 that is airtightly welded to the lower end of the body shell 11, and a bowl that is airtightly welded to the upper end of the body shell 11. It is formed by the upper shell 13 in the shape. An oil reservoir 15 is formed in the inner bottom 14 of the closed container 10.

The airtight container 10 is provided with a compression mechanism unit 20 and an electric motor unit 30. The compression mechanism unit 20 is arranged above the electric motor unit 30. The compression mechanism unit 20 and the electric motor unit 30 are connected by a drive shaft 40.

The compression mechanism unit 20 is composed of a fixed scroll 21 and a swivel scroll 22.
The fixed scroll 21 is composed of a end plate 21a and a spiral (involute) wrap 21b formed on the lower surface of the end plate 21a.
The swivel scroll 22 is composed of a end plate 22a and a spiral (involute) wrap 22b formed on the upper surface of the end plate 22a. A cylindrical boss 24 is provided at the center of the lower surface of the end plate 22a of the swivel scroll 22.
The lap 21b of the fixed scroll 21 and the lap 22b of the swivel scroll 22 are meshed with each other, and a plurality of compression chambers 23 are formed between the fixed scroll 21 and the swivel scroll 22 by both

laps

21b and 22b.
A discharge hole 25 is provided in the central portion of the end plate 21a of the fixed scroll 21, and a discharge valve 26 is provided in the discharge hole 25. A suction unit 28 for sucking a low-pressure refrigerant is provided on the outer circumference of the fixed scroll 21.

The electric motor unit 30 is composed of an annular stator 31 and a rotor 32 rotatably configured inside the stator 31. The stator 31 is fixed to the inner peripheral surface of the closed container 10. The rotor 32 is fixed to the drive shaft 40.

Above the inside of the closed container 10, a partition plate 50 that partitions the inside of the closed container 10 up and down is provided. The partition plate 50 divides the inside of the closed container 10 into a high-pressure space 16 and a low-pressure space 17. The high-pressure space 16 is a space filled with the high-pressure refrigerant after being compressed by the compression mechanism unit 20, and the low-pressure space 17 is a space filled with the low-pressure refrigerant before being compressed by the compression mechanism unit 20.

The closed container 10 includes a refrigerant suction pipe 18 that communicates the outside of the closed container 10 with the low pressure space 17, and a refrigerant discharge pipe 19 that communicates the outside of the closed container 10 with the high pressure space 16. The compressor introduces a low-pressure refrigerant into the low-pressure space 17 from a refrigeration cycle circuit (not shown) provided outside the closed container 10 via a refrigerant suction pipe 18. Further, the high-pressure refrigerant compressed by the compression mechanism unit 20 is first introduced into the high-pressure space 16. After that, it is discharged from the high pressure space 16 to the refrigeration cycle circuit via the refrigerant discharge pipe 19.

Below the fixed scroll 21 and the swivel scroll 22, a main bearing 60 for supporting the swivel scroll 22 is provided. The swivel scroll 22 is arranged between the fixed scroll 21 and the main bearing 60. The main bearing 60 has a bearing 61 formed in the center thereof and is fixed to the inner wall of the closed container 10.
A rotation suppressing member (oldam ring) 27 is provided between the swivel scroll 22 and the main bearing 60. The old dam ring 27 prevents the turning scroll 22 from rotating. As a result, the swivel scroll 22 makes a swivel motion without rotating with respect to the fixed scroll 21.

One end side of the drive shaft 40 is pivotally supported by the bearing 61, and the other end side is pivotally supported by the auxiliary bearing 70. An eccentric shaft 41 eccentric with respect to the axis of the drive shaft 40 is provided at the upper end of the drive shaft 40. The eccentric shaft 41 is slidably inserted into the boss 24 via the swing bush 41a and the swivel bearing 41b. The boss 24 is swiveled by the eccentric shaft 41.

An oil supply passage 42 through which lubricating oil passes is formed inside the drive shaft 40. The oil supply passage 42 is a through hole formed in the axial direction of the drive shaft 40. One end of the oil supply passage 42 is opened in the oil reservoir 15 as a suction port 42a provided at the lower end of the drive shaft 40. A paddle 43 for pumping lubricating oil from the suction port 42a to the oil supply passage 42 is provided above the suction port 42a.
The oil supply passage 42 guides the lubricating oil stored in the oil reservoir 15 to the compression mechanism 20 and the bearing 61.
The drive shaft 40 is formed with a communication hole 44 that communicates with the oil supply passage 42. The communication hole 44 functions as a degassing of the oil supply passage 42, and discharges the lubricating oil guided from the oil supply passage 42. The drive shaft 40 is formed with a bearing communication hole 42b that supplies lubricating oil to the main bearing 60. The bearing communication hole 42b communicates with the oil supply passage 42.

The auxiliary bearing 70 is provided below the low pressure space 17, preferably in the oil reservoir 15. The auxiliary bearing 70 includes a boss portion 71 that is formed in a cylindrical shape and into which a drive shaft 40 is inserted, and an arm portion 72 that extends from the boss portion 71 in the outer peripheral direction and is fixed to the inner peripheral surface of the closed container 10. ..

A balance weight 90 is provided on the drive shaft 40. The balance weight 90 is located below the compression mechanism unit 20 and above the electric motor unit 30.
The compression mechanism unit 20, the electric motor unit 30, the main bearing 60, the sub bearing 70, and the balance weight 90 are arranged in the low pressure space 17. The electric motor unit 30 and the balance weight 90 are arranged between the main bearing 60 and the auxiliary bearing 70.
Further, the fixed scroll 21 and the swivel scroll 22 are arranged between the partition plate 50 and the main bearing 60. The partition plate 50 and the main bearing 60 are fixed to the closed container 10. Of the fixed scroll 21 and the swivel scroll 22, at least one provided with an elastic body (not shown) is at least a part between the partition plate 50 and the main bearing 60, and more specifically, the partition plate 50 and swivel. It is provided so as to be movable in the axial direction between the scroll 22 or between the fixed scroll 21 and the main bearing 60.

A straightening vane 100 is provided between the refrigerant suction pipe 18 and the suction portion 28 of the compression mechanism portion 20. The straightening vane 100 is arranged at a position facing the suction port of the refrigerant suction pipe 18. By arranging the rectifying plate 100 at a position facing the suction port of the refrigerant suction pipe 18, an upper closed portion 100a is formed above the refrigerant suction pipe 18 side of the rectifying plate 100, and the refrigerant suction pipe 18 of the rectifying plate 100 is formed. A lower opening 100b is formed below the side.

The operation and operation of the compressor will be described below.
The drive shaft 40 rotates together with the rotor 32 by driving the electric motor unit 30. The eccentric shaft 41 and the old dam ring 27 cause the swivel scroll 22 to swivel around the central axis of the drive shaft 40 without rotating. As a result, the volume of the compression chamber 23 is reduced, and the refrigerant in the compression chamber 23 is compressed.

The refrigerant is introduced from the refrigerant suction pipe 18 into the low pressure space 17. Then, the refrigerant introduced into the low-pressure space 17 collides with the rectifying plate 100 and the upper closing portion 100a of the rectifying plate 100, and is rectified in the direction of the electric motor portion 30.
Then, the refrigerant rectified in the direction of the electric motor unit 30 is temporarily released into the low-pressure space 17, and the refrigerant in a turbulent flow state due to the drive of the electric motor unit 30 is sucked into the compression chamber 23 and compressed in the compression chamber 23. The refrigerant is discharged from the refrigerant discharge pipe 19 via the high-pressure space 16.

Next, the lubricating oil flow in the compressor according to this embodiment will be described.
The lubricating oil in the oil reservoir 15 is pumped into the oil supply passage 42 by the paddle 43. The lubricating oil pumped up into the oil supply passage 42 flows out from the communication hole 44, is supplied to the main bearing 60 from the bearing communication hole 42b, and is supplied into the boss 24 from the upper end opening of the drive shaft 40.
The lubricating oil supplied into the boss 24 is supplied to the sliding surface of the compression mechanism portion 20.
The lubricating oil flowing out of the communication hole 44 is mainly discharged into the low pressure space 17 through the gap between the balance weight 90 and the rotor 32.

FIG. 2 is an enlarged cross-sectional view of a main part of the compressor.
The balance weight 90 is formed in an arc shape in a plan view, and is fixed to the drive shaft 40 by the connecting portion 91.
The drive shaft 40 is formed with an enlarged diameter portion 40a, the rotor 32 is positioned by the lower end of the enlarged diameter portion 40a, and the balance weight 90 is positioned by the upper end of the enlarged diameter portion 40a. The rotor 32 has a protrusion 32b at the end of the iron core portion 32a.
The communication hole 44 is formed in the enlarged diameter portion 40a. Therefore, the communication hole 44 is located below the balance weight 90 and above the iron core portion 32a of the rotor 32. Further, the communication hole 44 is located on the inner circumference of the protrusion 32b of the rotor 32.

The balance weight 90 projects the lower end surface 90d of the balance weight 90 below the lower end 91d of the connecting portion 91 of the balance weight 90.
Further, the balance weight 90 projects the upper end surface 90u of the balance weight 90 upward from the upper end 91u of the connecting portion 91 of the balance weight 90. The upper end 91u of the connecting portion 91 of the balance weight 90 is positioned above the lower end surface 61d of the main bearing 60.

According to this embodiment, the lower end surface 90d of the balance weight 90 is projected downward from the lower end 91d of the connecting portion 91 of the balance weight 90, so that the lower end surface 90d of the balance weight 90 is used as the rotor 32 of the electric motor unit 30. Since they can be brought close to each other, the lubricating oil discharged from the communication hole 44 can be reduced from being mixed with the refrigerant existing in the low pressure space 17, and the amount of oil discharged from the closed container 10 can be reduced.
Further, according to this embodiment, the upper end surface 90u of the balance weight 90 is positioned above the upper end 91u of the connecting portion 91 of the balance weight 90 and above the lower end surface 61d of the main bearing 60, whereby the main bearing 60 It is possible to reduce the amount of lubricating oil dripping from the surface being mixed with the refrigerant existing in the low pressure space 17, and to reduce the amount of oil discharged from the closed container 10.

It is preferable that the gap dimension S between the lower end surface 90d of the balance weight 90 and the rotor 32 is smaller than the diameter D of the communication hole 44.
When the diameter D of the communication hole 44 is 3 mm and the gap size S between the lower end surface 90d and the rotor 32 is 6 mm and the amount of oil discharged is 100%, the balance weight 90 according to this embodiment is used to set the gap size S. When the oil discharge amount was changed to 2.7 mm, the oil discharge amount could be reduced to 26%, and when the gap size S was changed to 1 mm, the oil discharge amount could be reduced to 22%.
In particular, the amount of oil discharged can be significantly reduced by setting the gap dimension S to 20% or more and 60% or less of the diameter D of the communication hole 44.
The gap size S is preferably 1 mm or more and 2.7 mm or less.

In a compressor in which the electric motor unit 30, the compression mechanism unit 20, and the balance weight 90 are arranged in the low pressure space 17, and the refrigerant in the low pressure space 17 is compressed by the compression mechanism unit 20, the refrigerant is discharged from the communication hole 44. Since the lubricating oil mixed in the refrigerant in the low pressure space 17 is mixed with the refrigerant in the low pressure space 17, the lubricating oil mixed in the refrigerant in the low pressure space 17 is likely to be discharged together with the high pressure refrigerant discharged from the compression mechanism unit 20, but according to this embodiment. For example, since it is possible to reduce the mixing of the refrigerant in the low pressure space 17, the amount of oil discharged from the closed container 10 can be reduced.

The present invention is particularly suitable for low-pressure scroll compressors.

10 Airtight container 11 Body shell 12 Lower shell 13 Upper shell 14 Inner bottom 15 Oil reservoir 16 High pressure space 17 Low pressure space 18 Refrigerant suction pipe 19 Refrigerant discharge pipe 20 Compression mechanism 21 Fixed scroll 21a End plate 21b Wrap 22 Swivel scroll 22a End plate 22b Wrap 23 Compression chamber 24 Boss 25 Discharge hole 26 Discharge valve 27 Rotation suppression member (old dam ring)
28 Suction part 30 Electric motor part 31 Stator 32 Rotor 32a Iron core part 32b Protrusion part 40 Drive shaft 40a Diameter expansion part 41 Eccentric shaft 41a Swing bush 41b Swing bearing 42 Oil supply passage 42a Suction port 42b Bearing oil supply hole 43 Paddle 44 Plate 60 Main bearing 61 Bearing 61d Lower end surface 70 Sub-bearing 71 Boss part 72 Arm part 90 Balance weight 90d Lower end surface 90u Upper end surface 91 Connecting part 91d Lower end 91u Upper end 100 Straightening plate 100a Upper closing part 100b Lower opening D Diameter S Gap Size

Claims

A compression mechanism and an electric motor are provided in a closed container.
The compression mechanism portion is arranged above the electric motor portion,
The compression mechanism unit and the electric motor unit are connected by a drive shaft.
A balance weight is arranged above the electric motor unit and below the compression mechanism unit.
The balance weight is fixed to the drive shaft by a connecting portion, and the balance weight is fixed to the drive shaft.
An oil reservoir is formed on the inner bottom of the closed container.
The drive shaft is formed with an oil supply passage for guiding the lubricating oil stored in the oil reservoir portion to the compression mechanism portion and the bearing, and a communication hole for communicating with the oil supply passage.
The communication hole is located below the balance weight,
A compressor in which the lubricating oil guided from the oil supply passage is discharged from the communication hole.
A compressor characterized in that the lower end surface of the balance weight is projected downward from the lower end of the connecting portion of the balance weight.
The electric motor unit is composed of an annular stator and a rotor fixed to the drive shaft and rotatably arranged inside the stator.
The compressor according to claim 1, wherein the gap between the lower end surface of the balance weight and the rotor is made smaller than the diameter of the communication hole.
The compressor according to claim 2, wherein the gap size is 20% or more and 60% or less of the diameter of the communication hole.
The compressor according to claim 2 or 3, wherein the gap size is 1 mm or more and 2.7 mm or less.
A partition plate for partitioning the inside of the closed container into upper and lower parts is provided in the closed container.
With the partition plate, the inside of the closed container is filled with a high-pressure space filled with a high-pressure refrigerant after being compressed by the compression mechanism and a low-pressure refrigerant before being compressed by the compression mechanism. Partitioned into a low pressure space
The electric motor unit, the compression mechanism unit, and the balance weight are arranged in the low pressure space.
The compressor according to any one of claims 1 to 4, wherein the refrigerant in the low-pressure space is compressed by the compression mechanism unit.