JP7369934B2 - compressor - Google Patents

Description

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

Conventionally, hermetic compressors used in cooling devices, water heaters, etc. compress the refrigerant gas returned from the refrigeration cycle in the compression mechanism and send it to the refrigeration cycle, but at that time, lubricating oil is applied to the compression mechanism. The oil is supplied to lubricate its sliding parts, and the lubricated oil is released into the compressor and returned to the oil sump at the bottom of the compressor.
At this time, the refrigerant gas is in a turbulent flow inside the hermetic compressor, so a large amount of lubricating oil is mixed with the refrigerant, and a large amount of oil is discharged into the refrigeration cycle together with the compressed refrigerant. Put it away.
Therefore, in Patent Document 1, by providing a first seal member provided between the balance weight and the orbiting scroll and a second seal member provided between the balance weight and the frame, excessive This restricts the supply of oil.

Japanese Patent Application Publication No. 2018-17211

In Patent Document 1, the sealing material seals the gap between the balance weight that is press-fitted onto the crankshaft and the components above and below it, so the sealing material may be worn out or broken due to contact between the rotating body and the sealing material. etc. may occur, making it difficult to ensure reliability. Furthermore, the number of parts increases, leading to an increase in assembly man-hours and costs.

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

The compressor of the present invention according to claim 1 includes a compression mechanism section 20 and an electric motor section 30 in a closed container 10, the compression mechanism section 20 is arranged above the electric motor section 30, and the compression mechanism section 20 is arranged above the electric motor section 30. and the electric motor section 30 are connected by a drive shaft 40, a balance weight 90 is disposed above the electric motor section 30 and below the compression mechanism section 20, and the balance weight 90 is connected to the drive shaft 40 by a connection section 91. An oil reservoir 15 is formed in the inner bottom 14 of the closed container 10, and the drive shaft 40 guides the lubricating oil stored in the oil reservoir 15 to the compression mechanism 20 and the bearing 61. An oil supply passage 42 and a 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 led from the oil supply passage 42 flows through the communication hole. 44, a lower end surface 90d of the balance weight 90 is made to protrude below a lower end 91d of the connection part 91 of the balance weight 90, and the drive shaft 40 has an enlarged diameter. An enlarged diameter portion 40a is formed, the rotor 32 is positioned by the lower end of the enlarged diameter portion 40a, the balance weight 90 is positioned by the upper end of the enlarged diameter portion 40a, and the communication hole 44 is located in the enlarged diameter portion 40a. The present invention is characterized in that the gap size 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.
According to a second aspect of the present invention, in the compressor according to the first aspect , the gap size S is set to 20% or more and 60% or less of the diameter D of the communication hole 44.
A compressor of the present invention according to claim 3 is the compressor according to claim 1 or 2 , characterized in that the gap size S is 1 mm or more and 2.7 mm or less.
The compressor of the present invention according to claim 4 is the compressor according to any one of claims 1 to 3 , in which a partition plate is provided in the airtight container 10 to partition the inside of the airtight container 10 into upper and lower parts. 50 is provided, and the partition plate 50 allows the interior of the closed container 10 to be formed into a high-pressure space 16 filled with high-pressure refrigerant after being compressed by the compression mechanism section 20, and a high-pressure space 16 filled with high-pressure refrigerant compressed by the compression mechanism section 20. The electric motor section 30, the compression mechanism section 20, and the balance weight 90 are arranged in the low pressure space 17, and the The refrigerant is compressed by the compression mechanism section 20.

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

Side sectional view of a compressor according to an embodiment of the present invention Enlarged sectional view of main parts of the compressor

In the compressor according to the first embodiment of the present invention, the lower end surface of the balance weight protrudes below the lower end of the connection part of the balance weight , and the drive shaft is formed with an enlarged diameter part. The rotor is positioned by the lower end of the enlarged diameter part, the balance weight is positioned by the upper end of the enlarged diameter part, a communication hole is formed in the enlarged diameter part, and the gap size between the lower end surface of the balance weight and the rotor is determined by the communication hole. It is smaller than the diameter of . According to this embodiment, since the lower end surface of the balance weight can be brought close to the electric motor part, it is possible to reduce the lubricating oil discharged from the communication hole from mixing with the refrigerant, and the lubricating oil is mixed with the refrigerant and compressed. The amount of oil discharged from the sealed container that flows into the refrigeration cycle together with the refrigerant can be reduced. In addition, since the lubricating oil discharged from the communication hole is less likely to come out from the rotor, it is possible to reduce the possibility that the lubricating oil will mix with the refrigerant. The amount of oil discharged from the container can be reduced.

In the second embodiment of the present invention, in the compressor according to the first embodiment, the gap size is set to 20% or more and 60% or less of the diameter of the communication hole. According to this embodiment, since the lubricating oil discharged from the communication hole is difficult to come out from the rotor, it is possible to reduce the lubricating oil from being mixed 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 into the cycle can be reduced.

A third embodiment of the present invention is the compressor according to the first or second embodiment, in which the gap size is set to 1 mm or more and 2.7 mm or less. According to this embodiment, since the lubricating oil discharged from the communication hole is difficult to come out from the rotor, it is possible to reduce the lubricating oil from being mixed 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 into the cycle can be reduced.

A fourth embodiment of the present invention is a compressor according to any one of the first to third embodiments, in which a partition plate is provided in the airtight container to partition the inside of the airtight container into upper and lower parts, and by the partition plate, The inside of the airtight container is divided into a high-pressure space filled with high-pressure refrigerant after being compressed by the compression mechanism, and a low-pressure space filled with low-pressure refrigerant before being compressed by the compression mechanism. , an electric motor section, a compression mechanism section, and a balance weight are arranged, and the refrigerant in the low pressure space is compressed by the compression mechanism section. When the electric motor, compression mechanism, and balance weight are placed in a low-pressure space, the lubricating oil discharged from the communication hole mixes with the refrigerant in the low-pressure space. , is likely to be discharged together with the high-pressure refrigerant discharged from the compression mechanism, but according to the present embodiment, since it is possible to reduce the amount of refrigerant mixed into the refrigerant in the low-pressure space, it is mixed with the refrigerant and is used together with the compressed refrigerant in the refrigeration cycle. It is possible to reduce the amount of oil discharged from the closed container that flows into the container.

An embodiment of the present invention will be described below with reference to the drawings.
FIG. 1 is a side sectional view of a compressor according to this embodiment. Note that in this embodiment, a scroll compressor is used as the compressor.

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

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

The compression mechanism section 20 includes a fixed scroll 21 and an orbiting scroll 22.
The fixed scroll 21 includes an end plate 21a and an involute wrap 21b formed on the lower surface of the end plate 21a.
The orbiting scroll 22 includes an end plate 22a and an 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 orbiting scroll 22.
The wrap 21b of the fixed scroll 21 and the wrap 22b of the orbiting scroll 22 are engaged with each other, and a plurality of compression chambers 23 are formed between the fixed scroll 21 and the orbiting scroll 22 by the wraps 21b and 22b.
A discharge hole 25 is provided in the center of the end plate 21a of the fixed scroll 21, and a discharge valve 26 is provided in the discharge hole 25. A suction section 28 for sucking low-pressure refrigerant is provided on the outer periphery of the fixed scroll 21.

The electric motor section 30 includes 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 a drive shaft 40.

A partition plate 50 is provided above the inside of the closed container 10 to partition the inside of the closed container 10 into upper and lower parts. 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 high-pressure refrigerant after being compressed by the compression mechanism section 20, and the low-pressure space 17 is a space filled with low-pressure refrigerant before being compressed by the compression mechanism section 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 connects the outside of the closed container 10 with the high pressure space 16. The compressor introduces low-pressure refrigerant into the low-pressure space 17 from a refrigeration cycle circuit (not shown) provided outside the closed container 10 via the refrigerant suction pipe 18 . Further, the high-pressure refrigerant compressed by the compression mechanism section 20 is first introduced into the high-pressure space 16. Thereafter, the refrigerant is discharged from the high-pressure space 16 to the refrigeration cycle circuit via the refrigerant discharge pipe 19.

A main bearing 60 that supports the orbiting scroll 22 is provided below the fixed scroll 21 and the orbiting scroll 22. The orbiting scroll 22 is arranged between the fixed scroll 21 and the main bearing 60. The main bearing 60 has a bearing 61 formed in its center and is fixed to the inner wall of the closed container 10 .
A rotation suppressing member (Oldham ring) 27 is provided between the orbiting scroll 22 and the main bearing 60. The Oldham ring 27 prevents the orbiting scroll 22 from rotating. Thereby, the orbiting scroll 22 performs an orbiting motion without rotating relative to the fixed scroll 21.

One end of the drive shaft 40 is supported by a bearing 61, and the other end is supported by an auxiliary bearing 70. An eccentric shaft 41 eccentric 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 a swing bush 41a and a rotation bearing 41b. The boss 24 is rotationally driven by the eccentric shaft 41.

An oil supply path 42 through which lubricating oil passes is formed inside the drive shaft 40 . The oil supply path 42 is a through hole formed in the axial direction of the drive shaft 40. One end of the oil supply path 42 opens into 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 path 42 is provided above the suction port 42a.
The oil supply path 42 guides lubricating oil stored in the oil reservoir 15 to the compression mechanism 20 and the bearing 61.
A communication hole 44 communicating with the oil supply path 42 is formed in the drive shaft 40 . The communication hole 44 functions as a gas vent for the oil supply passage 42 and discharges the lubricating oil led from the oil supply passage 42 . Note that 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 path 42.

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

A balance weight 90 is provided on the drive shaft 40. The balance weight 90 is located below the compression mechanism section 20 and above the electric motor section 30.
The compression mechanism section 20, the electric motor section 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 section 30 and the balance weight 90 are arranged between the main bearing 60 and the sub-bearing 70.
Further, the fixed scroll 21 and the orbiting 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 orbiting scroll 22, at least one provided with an elastic body (not shown) is at least partially between the partition plate 50 and the main bearing 60, more specifically, between the partition plate 50 and the orbiting scroll. It is provided so as to be freely movable in the axial direction between the scroll 22 or between the fixed scroll 21 and the main bearing 60.

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

The operation and function of the compressor will be explained below.
By driving the electric motor section 30, the drive shaft 40 rotates together with the rotor 32. Due to the eccentric shaft 41 and the Oldham ring 27, the orbiting scroll 22 rotates 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 into the low pressure space 17 from the refrigerant suction pipe 18 . The refrigerant introduced into the low-pressure space 17 collides with the rectifying plate 100 and the upper closed portion 100a of the rectifying plate 100, and is rectified in the direction of the electric motor section 30.
The refrigerant that has been rectified in the direction of the electric motor section 30 is once released into the low-pressure space 17, and the refrigerant that has become turbulent due to the drive of the electric motor section 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 flow of lubricating oil in the compressor according to this embodiment will be explained.
The lubricating oil in the oil reservoir 15 is pumped up into the oil supply path 42 by the paddle 43. The lubricating oil pumped up into the oil supply path 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 section 20.
The lubricating oil flowing out from the communication hole 44 is mainly discharged into the low pressure space 17 from the gap between the balance weight 90 and the rotor 32.

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

The balance weight 90 has a lower end surface 90d projecting below a lower end 91d of the connecting portion 91 of the balance weight 90.
In addition, the balance weight 90 has an upper end surface 90u that projects higher than 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 located above the lower end surface 61d of the main bearing 60.

According to this embodiment, by making the lower end surface 90d of the balance weight 90 protrude below the lower end 91d of the connecting portion 91 of the balance weight 90, the lower end surface 90d of the balance weight 90 is connected to the rotor 32 of the electric motor section 30. Since they can be placed close to each other, the lubricating oil discharged from the communication hole 44 can be less likely to mix 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 located 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, so that the main bearing 60 It is possible to reduce the amount of lubricating oil dripping from the refrigerant that is present in the low-pressure space 17, and the amount of oil discharged from the closed container 10 can be reduced.

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

Note that in a compressor in which the electric motor section 30, the compression mechanism section 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 section 20, the refrigerant is discharged from the communication hole 44. Since the lubricating oil mixed with the refrigerant in the low-pressure space 17 is likely to be discharged together with the high-pressure refrigerant discharged from the compression mechanism section 20, this embodiment For example, since the amount of refrigerant mixed in the low-pressure space 17 can be reduced, 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 Trunk 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 section 21 Fixed scroll 21a End plate 21b Wrap 22 Orbiting scroll 22a End plate 22b Wrap 23 Compression chamber 24 Boss 25 Discharge hole 26 Discharge valve 27 Rotation suppressing member (Oldham ring)
28 Suction part 30 Electric motor part 31 Stator 32 Rotor 32a Iron core part 32b Projection part 40 Drive shaft 40a Expanded diameter part 41 Eccentric shaft 41a Swing bush 41b Swivel bearing 42 Oil supply path 42a Suction port 42b Bearing oil supply hole 43 Paddle 44 Communication hole 50 Partition Plate 60 Main bearing 61 Bearing 61d Lower end surface 70 Secondary bearing 71 Boss portion 72 Arm portion 90 Balance weight 90d Lower end surface 90u Upper end surface 91 Connection portion 91d Lower end 91u Upper end 100 Current plate 100a Upper closed portion 100b Lower opening D Diameter S Gap size

Claims (4)

A compression mechanism section and an electric motor section are provided in a sealed container,
the compression mechanism section is arranged above the electric motor section,
the compression mechanism section and the electric motor section are connected by a drive shaft;
The electric motor section includes an annular stator and a rotor fixed to the drive shaft and rotatably disposed inside the stator,
a balance weight is disposed above the electric motor section and below the compression mechanism section;
fixing the balance weight to the drive shaft by a connecting portion;
An oil reservoir is formed in the inner bottom of the sealed container,
The drive shaft is formed with an oil supply passage that guides lubricating oil stored in the oil reservoir to the compression mechanism and the bearing, and a communication hole that communicates with the oil supply passage,
The communication hole is located below the balance weight,
A compressor in which the lubricating oil led from the oil supply path is discharged from the communication hole,
a lower end surface of the balance weight protrudes below a lower end of the connecting portion of the balance weight ;
The drive shaft is formed with an enlarged diameter portion having an enlarged diameter,
positioning the rotor by a lower end of the enlarged diameter portion;
positioning the balance weight by the upper end of the enlarged diameter part;
forming the communication hole in the enlarged diameter portion;
A compressor characterized in that a gap between the lower end surface of the balance weight and the rotor is smaller than a diameter of the communication hole . The compressor according to claim 1 , wherein the gap size is set to 20% or more and 60% or less of the diameter of the communication hole. The compressor according to claim 1 or 2 , wherein the gap size is 1 mm or more and 2.7 mm or less. A partition plate is provided in the airtight container to partition the inside of the airtight container into upper and lower parts,
The interior of the airtight container is defined by the partition plate into a high-pressure space filled with high-pressure refrigerant after being compressed by the compression mechanism, and a high-pressure space filled with the low-pressure refrigerant before being compressed by the compression mechanism. divided into low pressure space,
disposing the electric motor section, the compression mechanism section, and the balance weight in the low pressure space,
The compressor according to any one of claims 1 to 3, wherein the refrigerant in the low pressure space is compressed by the compression mechanism.