CN111386397A

CN111386397A - Compressor and refrigeration cycle device

Info

Publication number: CN111386397A
Application number: CN201880075888.1A
Authority: CN
Inventors: 森山贵司; 河村雷人; 佐佐木圭; 关屋慎
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 2017-11-27
Filing date: 2018-08-27
Publication date: 2020-07-07
Anticipated expiration: 2038-08-27
Also published as: JPWO2019102673A1; JP6573743B1; WO2019102673A1; CN111386397B

Abstract

The compressor is provided with: a container having an oil reservoir; a compression mechanism unit which is disposed inside the container and compresses the refrigerant; a centrifugal separation unit for separating oil from the compressed refrigerant; a discharge pipe for discharging the refrigerant separated by the centrifugal separation unit to the outside of the container; and an oil collecting part disposed outside the centrifugal separation part and recovering the separated oil. The centrifugal separation part comprises: a cylindrical portion having a plurality of holes on a side surface thereof; and a swirling mechanism portion provided inside the cylindrical portion, forming a swirling flow that flows toward the discharge pipe while swirling inside the cylindrical portion by blowing out the refrigerant compressed by the compression mechanism portion, separating oil from the refrigerant by a centrifugal force of the swirling flow, and discharging the separated oil to outside of the cylindrical portion through the hole. This can suppress scattering of oil separated from the refrigerant, and reduce the amount of oil discharged to the outside of the compressor.

Description

Compressor and refrigeration cycle device

Technical Field

The present invention relates to a compressor and a refrigeration cycle apparatus including the compressor as a component.

Background

In a conventional compressor, oil for lubricating a sliding portion of the compressor may be discharged to the outside of the compressor from a discharge pipe together with a compressed refrigerant. When the oil is continuously discharged from the compressor in this way, the oil accumulated in the oil reservoir is continuously reduced, and the oil supplied to the sliding portion may run out and become insufficient in lubrication. Therefore, in patent document 1, oil is separated from the refrigerant compressed in the compression chamber by an oil separating mechanism, and the separated oil is returned to the oil reservoir, thereby suppressing a decrease in the oil reservoir.

Documents of the prior art

Patent document

Patent document 1: japanese laid-open patent publication No. 2008-88929

Disclosure of Invention

Problems to be solved by the invention

In the above patent document 1, as a mechanism for separating the refrigerant from the oil, a method is adopted in which the refrigerant gas discharged from the compression chamber is swirled in the separation chamber, and the oil is attached to the inner circumferential surface of the separation chamber by a centrifugal force to be separated. However, there are problems as follows: the oil adhered to the inner peripheral surface of the separation chamber is swirled up by the refrigerant gas flow and scattered, and is dispersed again in the refrigerant gas, so that the amount of oil discharged to the outside of the compression chamber is increased. In order to reduce the amount of oil discharged to the outside of the compressor, it is necessary to further increase the height of the oil separating mechanism, but there is a problem that the size of the compressor becomes large.

The present invention has been made to solve the above-described problems, and an object thereof is to provide a compressor and a refrigeration cycle apparatus in which scattering of oil separated from a refrigerant is suppressed and the amount of oil discharged to the outside of the compressor is small.

Means for solving the problems

The compressor of the present invention comprises:

a container having an oil reservoir;

a compression mechanism unit disposed inside the container and configured to compress a refrigerant sucked from outside the container;

a centrifugal separation unit that separates oil from the refrigerant compressed by the compression mechanism unit;

a discharge pipe for discharging the refrigerant having passed through the centrifugal separation unit to the outside of the container; and

an oil collecting part disposed outside the centrifugal separation part and recovering oil discharged from the centrifugal separation part,

the centrifugal separation part comprises:

a cylindrical portion having a plurality of holes on a side surface thereof; and

a swirl mechanism portion provided inside the cylindrical portion and configured to form a swirl flow that flows toward the discharge pipe while swirling inside the cylindrical portion by blowing out the refrigerant compressed by the compression mechanism portion,

the oil is separated from the refrigerant by the centrifugal force of the swirling flow, and the separated oil is discharged to the oil collecting portion through the hole.

Effects of the invention

According to the compressor of the present invention, the oil separated from the refrigerant by the centrifugal force in the centrifugal separation portion is discharged to the outside of the cylindrical portion from the plurality of holes formed in the side surface of the cylindrical portion, so that the oil adhering to the inner wall surface of the cylindrical portion is prevented from being swirled up by the flow of the refrigerant and scattering, and the amount of oil discharged to the outside of the compressor can be reduced.

Drawings

Fig. 1 is a schematic cross-sectional view showing a structure of a compressor 100 according to embodiment 1 of the present invention.

Fig. 2 is a perspective view of the swirling mechanism 22 located in the centrifugal separation portion in the compressor 100 according to embodiment 1 of the present invention.

Fig. 3 is a perspective view of the cylindrical portion 23 located at the centrifugal separation portion in the compressor 100 according to embodiment 1 of the present invention.

Fig. 4 is a perspective view of the swirling mechanism 22 located in the centrifugal separation portion in the modified example of the compressor 100 according to embodiment 1 of the present invention.

Fig. 5 is a perspective view of the swirling mechanism 22 located in the centrifugal separation portion in the modified example of the compressor 100 according to embodiment 1 of the present invention.

Fig. 6 is a perspective view of the swirling mechanism 22 located in the centrifugal separation portion in the modified example of the compressor 100 according to embodiment 1 of the present invention.

Fig. 7 is a perspective view of the swirling mechanism 22 located in the centrifugal separation portion in the modified example of the compressor 100 according to embodiment 1 of the present invention.

Fig. 8 is a perspective view of the cylindrical portion 23 located at the centrifugal separation portion in the modified example of the compressor 100 according to embodiment 1 of the present invention.

Fig. 9 is a perspective view of the cylindrical portion 23 located at the centrifugal separation portion in the modified example of the compressor 100 according to embodiment 1 of the present invention.

Fig. 10 is a schematic cross-sectional view of the cylindrical portion 23 located at the centrifugal separation portion in the modified example of the compressor 100 according to embodiment 1 of the present invention.

Fig. 11 is a perspective view of the cylindrical portion 23 located at the centrifugal separation portion in the modified example of the compressor 100 according to embodiment 1 of the present invention.

Fig. 12 is a schematic cross-sectional view of discharge space 20 in a modification of compressor 100 according to embodiment 1 of the present invention.

Fig. 13 is a schematic sectional view of the discharge space 20 in the compressor 101 according to embodiment 2 of the present invention.

Fig. 14 is a schematic cross-sectional view of the periphery of the discharge pipe 3 of the discharge space 20 in the compressor of the comparative example.

Fig. 15 is a schematic cross-sectional view of the periphery of the discharge pipe 3 of the discharge space 20 in the compressor 101 according to embodiment 2 of the present invention.

Fig. 16 is a schematic cross-sectional view of the discharge space 20 in a modification of the compressor 101 according to embodiment 2 of the present invention.

Fig. 17 is a schematic cross-sectional view of the periphery of the discharge pipe 3 of the discharge space 20 in the modified example of the compressor 101 according to embodiment 2 of the present invention.

Fig. 18 is a schematic sectional view of the discharge space 20 in the compressor 102 according to embodiment 3 of the present invention.

Fig. 19 is a schematic cross-sectional view of the discharge space 20 in a modification of the compressor 102 according to embodiment 3 of the present invention.

Fig. 20 is a schematic sectional view of the discharge space 20 in the modified example of the compressor 102 according to embodiment 3 of the present invention.

Fig. 21 is a perspective view of the inside of the discharge space 20 in a modification of the compressor 102 according to embodiment 3 of the present invention.

Fig. 22 is a schematic cross-sectional view of the discharge space 20 in a modification of the compressor 102 according to embodiment 3 of the present invention.

Fig. 23 is a schematic sectional view of the discharge space 20 in the compressor 103 according to embodiment 4 of the present invention.

Fig. 24 is a perspective view of the inside of the discharge space 20 in the compressor 103 according to embodiment 4 of the present invention.

Fig. 25 is a schematic view of the flow of the refrigerant in the radial cross section of the cylindrical portion 23 of the centrifugal separation portion.

Fig. 26 is a schematic view of the flow of the refrigerant in the radial cross section of the cylindrical portion 23 of the centrifugal separation portion.

Fig. 27 is a schematic cross-sectional view of the discharge space 20 in a modification of the compressor 103 according to embodiment 4 of the present invention.

Fig. 28 is a perspective view of the inside of the discharge space 20 in a modification of the compressor 103 according to embodiment 4 of the present invention.

Fig. 29 is a schematic sectional view of the structure of an oil return flow passage in the compressor 104 according to embodiment 5 of the present invention.

Fig. 30 is a schematic cross-sectional view of an oil return flow path in a modification of the compressor 104 according to embodiment 5 of the present invention.

Fig. 31 is a schematic cross-sectional view showing the structure of a compressor 105 according to embodiment 6 of the present invention.

Fig. 32 is a schematic sectional view showing the structure of a compressor 106 according to embodiment 7 of the present invention.

Fig. 33 is a schematic cross-sectional view showing a modification of compressor 106 according to embodiment 7 of the present invention.

Fig. 34 is a schematic diagram of the refrigeration cycle apparatus 200 according to embodiment 8.

Fig. 35 is a schematic diagram of a refrigeration cycle apparatus mounted with a conventional compressor.

Fig. 36 is a schematic diagram of the refrigeration cycle apparatus 201 according to embodiment 8.

Fig. 37 is a schematic diagram of a refrigeration cycle apparatus mounted with a conventional horizontal compressor.

Fig. 38 is a schematic cross-sectional view showing the structure of a compressor 107 according to embodiment 9 of the present invention.

Fig. 39 is a schematic cross-sectional view showing a modification of compressor 107 according to embodiment 9 of the present invention.

Fig. 40 is a schematic cross-sectional view showing a modification of compressor 107 according to embodiment 9 of the present invention.

Fig. 41 is a schematic cross-sectional view showing a modification of compressor 107 according to embodiment 9 of the present invention.

Detailed Description

Hereinafter, a compressor and a refrigeration cycle apparatus according to an embodiment of the present invention will be described with reference to the drawings and the like. In the drawings, including fig. 1, the same or corresponding portions are denoted by the same reference numerals and are common throughout the embodiments described below. The embodiments of the constituent elements shown throughout the specification are merely examples, and are not limited to the embodiments described in the specification. In the following drawings including fig. 1, the relationship of the size, shape, and the like of each constituent member may be different from the actual ones.

Embodiment mode 1

A compressor 100 according to embodiment 1 of the present invention will be described. Fig. 1 is a schematic cross-sectional view showing a structure of a compressor 100 according to embodiment 1 of the present invention. The double-line arrows in fig. 1 show the direction of gravity, and the dashed arrows show the main flow of oil. The compressor 100 according to embodiment 1 is one of the components of a refrigeration cycle apparatus used for applications such as an air conditioner, a refrigeration apparatus, a refrigerator, an ice chest, a vending machine, or a hot water supply apparatus. The compressor 100 according to embodiment 1 is a scroll compressor.

As shown in fig. 1, the compressor 100 according to embodiment 1 includes a compression mechanism 30 that compresses a refrigerant, an electric mechanism 40 that drives the compression mechanism 30, a rotary shaft 5 that receives a rotational driving force of the electric mechanism 40 and transmits the rotational driving force to the compression mechanism 30, and a container 1 that houses the compression mechanism 30 and the electric mechanism 40. A frame 4 for fixing the compression mechanism unit 30 to the container 1 is further provided between the compression mechanism unit 30 and the electric mechanism unit 40 in the container 1.

The compression mechanism portion 30 includes a power conversion mechanism portion 6, a swing scroll 7 attached to the power conversion mechanism portion 6 and performing a swing motion, and a fixed scroll 8 fixed to the frame 4. The power conversion mechanism 6 is a mechanism that is attached to the rotary shaft 5 rotationally driven by the electric mechanism 40 and converts a rotational driving force into a compression driving force. A wrap 7a is formed on one surface of the orbiting scroll 7, and a wrap 8a is formed on one surface of the fixed scroll 8. The oscillating scroll 7 and the fixed scroll 8 are combined in such a manner that the wraps 7a, 8a mesh with each other. Thereby, a plurality of compression chambers 9 partitioned from each other by the wrap 7a or the wrap 8a are formed between the orbiting scroll 7 and the fixed scroll 8.

One end of the rotating shaft 5 is rotatably supported by the frame 4 and the power conversion mechanism 6, and the other end is rotatably supported by the sub-frame 10. The subframe 10 is fixed to the container 1. In fig. 1, the detailed connection structure and position of the rotary shaft 5, the frame 4, and the power conversion mechanism 6 are not illustrated. In fig. 1, the detailed connection structure and position between the rotary shaft 5 and the sub-frame 10 are not shown.

A rotor 11 of the electric mechanism unit 40 is attached to a portion between one end and the other end of the rotary shaft 5. The stator 12 of the electric mechanism unit 40 is disposed so as to cover the outer periphery of the rotor 11, and the stator 12 is attached to the container 1.

The container 1 is constituted by combining three parts of a bottomed cylindrical upper container 1a, a cylindrical side container 1b, and a bottomed cylindrical lower container 1 c. A suction pipe 2 for sucking a low-pressure refrigerant from the outside of the compressor is attached to the side tank 1b, and a discharge pipe 3 for discharging a compressed high-pressure refrigerant to the outside of the compressor is attached to the upper tank 1 a. The internal space of the container 1 is divided by the frame 4 into a suction space 19 on the suction pipe 2 side and a discharge space 20 on the discharge pipe 3 side, and the electric mechanism 40 is disposed in the suction space 19.

An oil reservoir 16 for storing oil is provided at the bottom of the container 1. An oil pump 18 that extracts oil accumulated in the oil reservoir 16 is provided at an end of the rotary shaft 5 on the sub-frame 10 side. An oil supply pipe 17 extending toward the oil reservoir 16 is connected to the oil pump 18, and a suction port 17a of the oil supply pipe 17 is immersed in the oil reservoir 16. The oil pump 18 pumps the oil in the oil reservoir 16 through the oil supply pipe 17 and supplies the oil to the respective sliding portions in the compressor 100, such as the power conversion mechanism portion 6, through the oil supply line 13 formed inside the rotary shaft 5.

Further, since the height position of the oil surface of the oil reservoir 16 varies depending on the use environment and the operating conditions, the height position of the suction port 17a is adjusted so that the suction port 17a is immersed in the oil under all conditions to avoid interruption of the supply of the oil. In this example, the oil pump 18 is provided at the end of the rotary shaft 5 on the sub-frame 10 side, but may be provided at the end of the rotary shaft 5 on the frame 4 side. As the oil pump 18, oil pumps of various structures can be used.

The frame 4 is provided with a suction port 14, and the suction port 14 serves as a flow path through which refrigerant flows from the suction space 19 to the compression chamber 9. The frame 4 and the fixed scroll 8 are provided with discharge holes 15, and the discharge holes 15 serve as flow paths through which the refrigerant flows from the compression chamber 9 to the discharge space 20. A check valve 21 for suppressing backflow of the refrigerant from the discharge space 20 to the compression chamber 9 is provided at the outlet end of the discharge hole 15. In addition, the discharge space 20 is provided with a discharge pipe 3 for discharging the refrigerant to the outside of the compressor. A centrifugal separation portion is provided between the discharge hole 15 and the discharge pipe 3, and most of the refrigerant compressed in the compression chamber 9 and discharged from the discharge hole 15 passes through the centrifugal separation portion and is discharged from the discharge pipe 3 to the outside of the compressor. Further, an oil collecting portion 20a is provided outside the centrifugal separation portion, and the oil separated in the centrifugal separation portion is collected to the oil collecting portion 20 a.

The centrifugal separation portion is provided with a cylindrical portion 23 having a plurality of holes in a side wall thereof, and a swirl mechanism portion 22 for changing the direction of the flow of the refrigerant discharged from the discharge holes 15 so as to flow in the circumferential direction of the cylindrical portion 23 and generating a swirl flow in the cylindrical portion 23. Further, the discharge pipe 3 is disposed so as to be located on the central axis of the cylindrical portion 23.

Fig. 2 is a perspective view of the swirling mechanism 22 located in the centrifugal separation portion in the compressor 100 according to embodiment 1 of the present invention. The arrows of the broken lines in fig. 2 show the flow of the refrigerant and the oil inside the swirl mechanism portion 22. The swirl mechanism 22 is disposed so as to cover the discharge hole 15 and the check valve 21, and forms a spiral flow path 22a so as to generate a swirl flow by changing the direction of the refrigerant and oil discharged from the discharge hole 15 and the check valve 21. An outlet port for blowing out the refrigerant and the oil in the circumferential direction of the cylindrical portion 23 is provided at an end portion of the spiral flow path 22 a.

Fig. 3 is a perspective view of the cylindrical portion 23 located at the centrifugal separation portion in the compressor 100 according to embodiment 1 of the present invention. The solid arrows of fig. 3 show the flow of the refrigerant, and the dotted arrows of fig. 3 show the flow of the oil. A swirl mechanism portion 22 is provided inside the cylindrical portion 23 so as to form a swirl flow inside the cylindrical portion 23. A plurality of holes 23a for discharging oil separated from the refrigerant by the centrifugal force of the swirling flow to the oil collecting portion 20a outside the cylindrical portion 23 are provided in the side wall of the cylindrical portion 23. A discharge pipe 3 for discharging the separated refrigerant to the outside of the compressor is disposed above the cylindrical portion 23.

Hereinafter, a direction of separating from the compression mechanism section 30 along the axial direction of the rotary shaft 5 is defined as "up" and a direction opposite thereto is defined as "down" with reference to the check valve 21 for discharging the refrigerant gas. When the height in the axial direction is viewed with reference to the position of the check valve 21, the cylindrical portion 23 extends to a higher position than the swivel mechanism portion 22 and to the vicinity of the inlet of the discharge pipe 3. The lower end of the cylindrical portion 23 is closely attached to the upper surface of the frame 4 without a gap. The cylindrical portion 23 has no hole 23a in a lower region thereof and has a plurality of holes 23a in an upper region thereof.

The hole 23a is not formed at a height at which the refrigerant is blown out from the swirling mechanism 22, that is, at a height at which the swirling flow starts to be generated, but is formed directly above the height. The distance from the height of the air outlet of the swirling mechanism portion to the lower end of the region where the hole 23a is formed, that is, the height of the hole 23a located at the lowermost position is preferably smaller than the height of the swirling mechanism portion 22. The height of the region in which the plurality of holes 23a are formed is preferably larger than the height of the swiveling mechanism 22, and may be, for example, 2 to 5 times. In addition, the aperture ratio of the region having the plurality of holes 23a in the side surface of the cylindrical portion 23 is preferably, for example, less than 50%. If the aperture ratio is too high, the refrigerant gas leaking to the outside of the cylindrical portion 23 through the passage holes 23a increases, and a stable swirling flow may not be formed inside the cylindrical portion 23.

As shown in fig. 1, the oil collector 20a is a space surrounded by the outer peripheral surface of the cylindrical portion 23, the inner wall surface of the upper container 1a, and the upper surface of the frame 4, and is provided outside the centrifugal separation portion in the discharge space 20. The oil discharged from the plurality of holes 23a of the cylindrical portion 23 of the centrifugal separation portion is collected into the oil collection portion 20 a. The lower surface of the oil collection portion 20a functions as an oil bearing surface that receives and temporarily holds the oil discharged from the centrifugal separation portion to the oil collection portion 20a and collected therebelow by gravity. In fig. 1, the upper surface of the frame 4 is an oil bearing surface, but an oil bearing surface may be provided separately from the frame 4, or the upper surface of the fixed scroll 8 may be an oil bearing surface without using the upper surface of the frame 4 as an oil bearing surface.

As shown in fig. 1, an oil return pipe 24 is provided in the frame 4 and the suction space 19 as an oil return flow path for returning the oil discharged from the centrifugal separation portion and collected in the oil collection portion 20a to the oil reservoir portion 16. The oil collected in the oil collecting portion 20a flows toward the oil reservoir 16 located on the suction space 19 side together with a part of the refrigerant due to the pressure difference between the discharge space 20 and the suction space 19. The end of the oil collection portion 20a side of the oil return pipe 24 is preferably disposed at a lower position of the oil collection portion 20a so that the oil collected to the oil collection portion 20a and collected to the lower position of the oil collection portion 20a by gravity flow flows into the oil return pipe 24. The diameter of the internal flow path of the oil return pipe 24 is preferably adjusted to be large enough so that the oil flows smoothly to the oil reservoir 16 without being excessively accumulated in the oil collection portion 20 a. Further, the diameter of the internal flow path of the oil return pipe 24 is preferably adjusted to be sufficiently small so as to avoid a decrease in compression efficiency and volumetric efficiency due to an excessive amount of refrigerant flowing from the discharge space 20 to the suction space 19 side through the oil return pipe 24. The oil return pipe 24 may join a flow path of the oil flowing out through the oil supply line 13 to lubricate the power conversion mechanism 6 in the middle of flowing from the oil collecting portion 20a to the oil reservoir portion 16, and may discharge the oil to the suction space 19.

Further, in order to lubricate the lap 7a of the orbiting scroll 7 and the lap 8a of the fixed scroll 8, the frame 4 or the fixed scroll 8 may be provided with a flow path through which a part of the oil supplied to the power conversion mechanism 6 through the oil supply line 13 flows to the suction port 14 or the compression chamber 9.

In the compressor 100 configured as described above, when the electric mechanism 40 is energized, torque is applied to the rotor 11 to rotate the rotary shaft 5, and the orbiting scroll 7 performs an orbiting motion with respect to the fixed scroll 8. Thereby, the refrigerant is compressed in the compression chamber 9. In this process, a part of oil droplets contained in the refrigerant in the suction space 19 or a part of oil flowing through the oil supply line 13 to the power conversion mechanism 6 flows into the compression chamber 9 through the suction port 14 together with the refrigerant.

The refrigerant containing the oil flowing into the compression chamber 9 is compressed and flows into the swirling mechanism 22 of the centrifugal separation portion through the discharge hole 15 and the check valve 21. The oil that has flowed into the compression chamber 9 lubricates the wrap 7a of the orbiting scroll 7 and the wrap 8a of the fixed scroll 8, and flows into the orbiting mechanism 22 together with the refrigerant. In the swirl mechanism portion 22, the refrigerant and the oil flow into the inside of the cylindrical portion 23 as a swirl flow, and in the cylindrical portion 23, the refrigerant and the oil are separated by the centrifugal force of the swirl flow. Most of the refrigerant rises while swirling inside the cylindrical portion 23, and is discharged from the discharge pipe 3 to the outside of the compressor. The oil is discharged from a plurality of holes 23a formed in the wall surface of the cylindrical portion 23 to the oil collecting portion 20a outside the cylindrical portion 23, and flows to the oil reservoir 16 through the oil return pipe 24.

More specifically, the swirling mechanism 22 generates a swirling flow below the cylindrical portion 23. The swirling flow rises while flowing along the inner wall surface of the cylindrical portion 23, and is discharged from the discharge pipe 3 located near the center of the cylindrical portion 23 to the outside of the container. In the interior of the cylindrical portion 23, centrifugal force acts strongly on oil (oil droplets and oil mist contained in the refrigerant gas) having a higher density than the refrigerant gas due to the swirling flow, and the oil flies toward the inner wall of the cylindrical portion 23. Then, a part of the oil is directly discharged to the outside of the cylindrical portion 23 through the hole 23a, and the remaining oil adheres to the inner wall surface of the cylindrical portion 23 to form an oil film. Since the swirling flow of the refrigerant gas flows closely to the inside of the oil film, the oil film is pushed by the flow to the position of the hole 23 a. Then, the position of the edge of the hole 23a is peeled off from the edge of the hole 23a again by the centrifugal force, or pushed out to the outside of the cylindrical portion 23 along the inner surface of the hole 23 a. In this way, the oil separated from the refrigerant is discharged from the plurality of holes 23a provided in the cylindrical portion 23 to the oil collecting portion 20a outside the cylindrical portion 23.

The oil discharged to the oil collecting portion 20a falls down by gravity, or flows by gravity after adhering to the outer wall surface of the cylindrical portion 23 or the inner wall surface of the upper container 1a, and collects on the upper surface of the frame 4 corresponding to the lower surface of the oil collecting portion 20 a. The oil collected on the upper surface of the frame 4 flows in the oil return pipe 24 together with a part of the refrigerant due to gravity and a pressure difference between the discharge space 20 and the suction space 19, and is discharged to the suction space 19. The oil discharged into the suction space 19 partly becomes oil droplets and flows into the compression chamber 9 again through the suction hole 14, but most of the oil flows into the oil reservoir 16 below due to gravity.

In the conventional compressor described in patent document 1, a centrifugal separation mechanism having the following structure is used: a swirling flow of the refrigerant is generated inside the cylindrical portion, oil is attached to the inner wall surface of the cylindrical portion by a centrifugal force, and the oil attached to the inner wall surface of the cylinder is collected downward by gravity and separated. However, in such a configuration, while the oil adhering to the inner wall surface of the cylinder flows downward by gravity and collects, the oil is scattered by a strong shearing force generated by the swirling flow of the refrigerant, and is again dispersed as fine oil droplets in the refrigerant, and is easily discharged directly to the outside of the compressor together with the refrigerant. Although the height of the cylindrical portion may be sufficiently increased in order to reduce the amount of oil discharged to the outside of the compressor, the discharge space above the compressor is increased, and the size of the compressor is increased.

In contrast, in the compressor 100 of embodiment 1, the oil adhering to the inner wall surface of the cylindrical portion 23 is quickly discharged from the plurality of holes 23a formed in the wall surface of the cylindrical portion 23 to the oil collecting portion 20a outside the cylindrical portion 23 by the centrifugal force of the swirling flow in the centrifugal separation portion. In this way, the oil is discharged to the oil collecting portion 20a and separated from the swirling flow inside the cylindrical portion 23, and the oil adhering to the inner wall surface of the cylindrical portion 23 is suppressed from being swirled up and scattering. This can greatly reduce the amount of oil discharged from the discharge pipe 3 to the outside of the compressor. In addition, even in a compressor having a centrifugal separation portion in the interior thereof and having a low height, the amount of oil discharged to the outside of the compressor can be sufficiently reduced.

Further, it is preferable that the lower end of the cylindrical portion 23 is connected to the lower surface of the oil collecting portion 20a without a gap, and the hole 23a is not formed in a lower region of the side surface of the cylindrical portion 23 adjacent to the lower end of the cylindrical portion 23. That is, it is preferable that no hole 23a is formed from the lower end of the cylindrical portion 23 to a certain height. For example, it is preferable that the hole 23a is not formed at a position lower than the height of the air outlet of the swiveling mechanism section 22. Thus, the lower region of the side wall of the cylindrical portion 23 serves as a partition wall, and the oil collected on the lower surface of the oil collecting portion 20a is suppressed from entering the inside of the cylindrical portion 23.

In this lower region, the swirling flow inside the cylindrical portion 23 is not blown out to the outside of the cylindrical portion 23, and therefore, the oil collected on the lower surface of the oil collecting portion 20a is prevented from being curled up. This can further reduce the amount of oil discharged to the outside of the compressor. In the interior of the cylindrical portion 23, the refrigerant flow rising while swirling is pushed up to the hole 23a along the inner wall surface of the cylindrical portion 23 by the oil adhering to the inner wall surface or the cylindrical bottom surface of the cylinder in the lower portion where the hole 23a is not formed, and is pushed out from the hole 23a to the outside of the cylindrical portion. Therefore, a large amount of oil does not accumulate inside the cylindrical portion 23.

Further, it is preferable that the hole 23a provided on the side surface of the cylindrical portion 23 is not formed at the same height as the outlet of the swirling mechanism portion 22. This enables the refrigerant gas discharged from the discharge port of the swirling mechanism section 22 to reliably flow along the inner wall surface of the cylindrical section 23, thereby forming a strong and stable swirling flow. The "same" height does not need to be exactly the same, but means substantially the same height to the extent that the refrigerant gas discharged from the discharge port of the swirling mechanism portion 22 is in direct contact with it.

Further, the strength of the swirling flow tends to be as follows: the air is strongest immediately after exiting from the outlet of the swirling mechanism 22, and weakens as it rises from the outlet of the swirling mechanism 22 toward the discharge pipe 3. Therefore, if the region in which the hole 23a is formed is located at a height directly above the outlet port of the swirl mechanism section 22, the oil can be more efficiently discharged to the outside of the cylinder. For example, the distance from the height of the air outlet of the swirling mechanism portion to the lower end of the region where the hole 23a is formed, that is, the height of the hole 23a located at the lowermost position may be made smaller than the height of the swirling mechanism portion 22.

In the region of the side surface of the cylindrical portion 23 where the plurality of holes 23a are formed, the total ratio of the opening areas of the holes 23a in this region is preferably less than 50%, for example. If the ratio of the opening area of the holes 23a is too large, the amount of refrigerant leaking out of the cylindrical portion 23 through the holes 23a increases, the amount of refrigerant inside the cylindrical portion 23 decreases, the swirling flow weakens, and there is a possibility that the oil separation efficiency decreases. By reducing the ratio of the opening area, the amount of refrigerant leaking out of the cylindrical portion 23 through the passage holes 23a can be reduced, and a strong swirling flow can be formed inside the cylindrical portion 23.

In embodiment 1, even when starting the compressor 100 from a state in which a large amount of liquefied refrigerant is accumulated in the compressor 100, the amount of oil discharged from the compressor 100 can be reduced. When the compressor is stopped, the refrigerant gas inside the compressor liquefies, and a large amount of liquefied refrigerant may accumulate in the suction space 19 inside the compressor. When the compressor is started from this state, a large amount of oil flows into the compression chamber 9 through the suction hole 14 and flows into the discharge space 20 through the discharge hole 15 due to foaming of the oil reservoir 16 and agitation by the rotor 11 caused by rapid vaporization of the refrigerant. At this time, if the oil return to the oil reservoir 16 through the oil return pipe 24 cannot follow, the oil is temporarily accumulated in the discharge space 20.

In embodiment 1 of the present invention, a large amount of oil that has flowed into the discharge space 20 is discharged to and accumulated in the large oil collecting portion 20a outside the cylindrical portion 23 through the plurality of holes 23 a. Therefore, a large amount of oil is not continuously exposed to the strong swirling flow of the refrigerant inside the cylindrical portion 23 and is not raised to the oil surface. In particular, the lower portion of the cylindrical portion 23 is connected to the upper surface of the frame 4 corresponding to the lower surface of the oil collecting portion 20a without a gap, and no hole 23a is formed in the lower region of the side wall of the cylindrical portion 23. Therefore, this portion serves as a partition wall, and the oil held in the oil collecting portion 20a outside the cylindrical portion 23 does not enter the inside of the cylindrical portion 23. Further, since the swirling flow inside the cylinder does not flow out from the lower portion of the cylinder to the outside of the cylinder portion, the oil accumulated in the lower position of the oil collecting portion 20a is prevented from being curled up.

After that, as the foaming of the oil reservoir 16 and the stirring by the rotor 11 are reduced and the amount of the oil flowing into the discharge space 20 is reduced to return to a normal amount, the oil accumulated in the oil collector 20a gradually flows through the oil return pipe 24 and returns to the oil reservoir 16. As described above, even when a large amount of oil flows into the discharge space 20 at the time of starting, the amount of oil discharged to the outside of the compressor 100 can be reduced.

In the conventional compressor described in patent document 1, the flow path is configured to be repeatedly bent, rapidly expanded, and rapidly contracted before the refrigerant compressed by the compression mechanism section is discharged to the outside of the compressor from the discharge pipe, and therefore, the pressure loss increases and the compression efficiency decreases. In contrast, in the present invention, the refrigerant compressed in the compression chamber 9 immediately flows into the swirling mechanism 22 through the discharge hole 15 to become a swirling flow, and then rises while swirling inside the cylindrical portion 23, and is discharged from the discharge pipe 3 to the outside of the compressor 100. Therefore, the flow path can be prevented from being bent, rapidly expanded, and rapidly contracted to the minimum. Therefore, the pressure loss becomes small, and the reduction of the compression efficiency is suppressed.

In addition, embodiment 1 of the present invention can reduce noise generated during operation of the compressor 100. The discharge space 20 of the compressor 100 is partitioned by the cylindrical portion 23 into an outer space and an inner space, and the two spaces are communicated with each other through the plurality of holes 23 a. This structure is a resonance type noise reduction structure, and particularly, noise in a specific frequency band can be greatly reduced. The thickness or cross-sectional area of the cylindrical portion 23 and the number or cross-sectional area of the plurality of holes 23a provided in the cylindrical portion 23 may be adjusted to adjust the noise of the frequency band to be reduced.

Fig. 4 to 7 are perspective views of the swirling mechanism 22 located in the centrifugal separation portion in the modified example of the compressor 100 according to embodiment 1 of the present invention. The arrows of broken lines in fig. 4 to 7 show the flows of the refrigerant and the oil inside the swirling mechanism portion 22. Fig. 2 shows a structure in which the swirling mechanism 22 forms a spiral flow path so as to generate a swirling flow by changing the direction of the refrigerant and oil flowing from the check valve 21 through the discharge hole 15, but the present invention is not limited to this, and the swirling mechanism 22 having the structure shown in fig. 4 to 7 may be used.

As shown in fig. 4 to 6, a plurality of outlets of the swirling mechanism 22 may be provided. The plurality of outlets are preferably arranged uniformly in the circumferential direction of the cylindrical portion 23, and are preferably arranged at positions point-symmetrical about the center axis of the cylindrical portion 23, for example. In the example shown in fig. 4, the swirl mechanism 22 radially diffuses the refrigerant and the oil flowing from the discharge hole 15. The swirling mechanism 22 includes a disc 22b disposed above the check valve 21. The swirling mechanism 22 has a structure in which a plurality of blades 22c are provided between the frame 4 and the disc 22b so as to change the flow direction of the refrigerant and oil radially diffused to a direction tangential to the circumferential direction of the cylindrical portion 23.

In such a swirling mechanism portion 22, the generated swirling flow is more uniformly distributed in the circumferential direction than in the swirling mechanism portion 22 shown in fig. 2. If the swirl flow is not uniform inside the cylindrical portion 23, a region where the swirl flow is slow and the centrifugal force is weak is generated in a portion near the inner wall surface of the cylindrical portion 23, and there is a possibility that the refrigerant and oil droplets enter the region inside the cylindrical portion 23 from outside the cylindrical portion 23. If the swirling flow is uniform in the circumferential direction, the generation of the above-described region is reduced, and oil can be separated from the refrigerant more efficiently.

The plurality of blades 22c may have an arc-shaped or wing-shaped cross section. When the plurality of blades 22c have an arc-shaped or wing-shaped cross section, a pressure loss generated when the flow direction of the refrigerant and the oil is changed can be reduced, and a reduction in compression efficiency of the compressor 100 can be prevented.

In the example shown in fig. 5, the swirl mechanism 22 radially diffuses the refrigerant and the oil flowing in through the discharge hole 15. The swirling mechanism 22 includes a disc 22b disposed above the check valve 21. A plurality of cutouts 22d are provided in the disk 22b in a radial shape. The cut-and-raised surface 22d may be formed to be directed obliquely upward or obliquely downward with respect to the circumferential direction so as to swirl the refrigerant and oil flowing from the frame 4 side to the cylindrical portion 23 side through the cut-and-raised hole. Since the swirling mechanism 22 can generate a swirling flow only by providing the disc 22b provided with the cutouts 22d that are easy to machine, the compressor 100 of the present invention can be manufactured more easily.

In the example shown in fig. 6, two spiral flow paths 22a are provided in the swirling mechanism 22 as shown in the example of fig. 2. As shown in this example, a plurality of flow paths 22a for generating swirling flows may be provided. By providing the plurality of flow paths 22a generating the swirling flow in this manner, the swirling flow is generated from the plurality of flow paths 22a of the swirling mechanism portion 22 and is dispersed in the circumferential direction inside the cylindrical portion 23. Therefore, the swirling flow inside the cylindrical portion 23 is uniformly distributed in the circumferential direction, and oil can be more efficiently separated from the refrigerant.

As in the example shown in fig. 7, the swirl mechanism 22 may have a spiral flow path 22a formed by a spiral plate 22e and the inner wall surface of the cylindrical portion 23. In such a configuration, a swirling flow of the refrigerant and the oil can be generated along the spiral plate 22e in the swirling mechanism portion 22.

Fig. 8, 9, and 11 are perspective views of the cylindrical portion 23 located at the centrifugal separation portion in the modified example of the compressor 100 according to embodiment 1 of the present invention. Fig. 10 is a cross-sectional view of the cylindrical portion 23 located at the centrifugal separation portion in the modified example of the compressor 100 according to embodiment 1 of the present invention. Solid-line arrows in fig. 8 to 11 show the main flow of the refrigerant, and broken-line arrows show the main flow of the oil.

In the example shown in fig. 8, the plurality of holes 23a provided in the cylindrical portion 23 have a longitudinally elongated shape. In the example shown in fig. 9, the long sides of the holes 23a formed in an elongated shape are inclined. The inclination direction of the long side of the hole 23a is a direction in which the intersection angle between the direction of the swirling flow that rises along the inner wall surface of the cylindrical portion 23 while swirling in the vicinity of the inner wall surface of the cylindrical portion 23 and the long side of the hole 23a becomes large.

The oil adhering to the inner wall surface of the cylindrical portion 23 receives a shearing force from the swirling flow of the refrigerant flowing in the vicinity, and flows in the direction of the swirling flow on the inner wall surface of the cylindrical portion 23. In the example shown in fig. 8 and 9, the plurality of holes 23a provided in the cylindrical portion 23 are elongated along the cylindrical surface, that is, the long sides of the holes 23a intersect the direction of the swirling flow flowing near the inner wall surface of the cylindrical portion. Therefore, when the oil adhered to the inner wall surface of the cylindrical portion 23 flows in the direction of the swirling flow on the inner wall surface, the oil easily reaches any one of the plurality of holes 23a, and is easily discharged to the oil collecting portion 20a outside the cylindrical portion 23 through the plurality of holes 23 a. In the example shown in fig. 9, the intersection angle between the direction of the swirling flow near the inner wall surface of the cylindrical portion 23 and the long side of the hole 23a is increased and becomes close to a right angle, so that the oil flowing on the inner wall surface of the cylindrical portion 23 easily and reliably reaches the hole 23 a.

Fig. 10 shows a cross-sectional view of the cylindrical portion 23. In the example shown in fig. 10, a plurality of holes 23a provided in the cylindrical portion 23 are formed from the inner wall surface side to the outer wall surface side while being inclined from the radial direction of the cylindrical portion 23 to the same direction as the swirling direction of the swirling flow of the refrigerant. According to this configuration, the oil adhered to the inner wall surface of the cylindrical portion 23 or the oil droplets flowing near the inner wall surface of the cylindrical portion 23 hardly flow from the direction along the swirling flow of the refrigerant gas to the plurality of holes 23a provided in the cylindrical portion 23 while turning. Therefore, the amount of oil discharged to the oil collecting portion 20a can be further increased.

In the example shown in fig. 11, the cylindrical portion 23 is formed using the air gap structure 23b, instead of providing the plurality of holes 23a in the cylindrical portion 23. The void structure 23b has, for example, a porous (continuous porous) structure, a flocculent, a lattice structure, or a mesh structure. In such a structure, when oil droplets adhere to the gap structures 23b due to the centrifugal force of the swirling flow of the refrigerant, the oil enters the gaps of the gap structures 23b due to surface tension, and the oil is less likely to scatter even if it receives a shearing force generated by the swirling flow of the refrigerant.

The oil adhered to the gap structure 23b is discharged to the oil collecting portion 20a outside the cylindrical portion 23 through the gap of the gap structure 23b by a pressure difference between the inside and the outside of the cylindrical portion 23. In addition, when there are solid foreign matters or the like flowing into the centrifugal separation portion of the discharge space 20 through the discharge holes 15 together with the refrigerant and the oil, the solid foreign matters are caught by the gap structure 23b of the cylindrical portion 23 due to the centrifugal force of the swirling flow of the refrigerant. Therefore, by configuring the cylindrical portion 23 using the gap structure 23b, it is suppressed that solid foreign matter is discharged from the discharge pipe 3 to the outside of the compressor 100 together with the refrigerant, and blocks the oil return pipe 24 or is discharged to the suction space 19 through the oil return pipe 24 together with oil. This can reduce the frequency of occurrence of a trouble due to mixing of solid foreign matter into a lubricating portion, an oil flow path, and the like inside the compressor 100 or each device connected to a refrigerant line outside the compressor 100.

In the example of fig. 11, if the lower portion of the cylindrical portion 23 is formed of a non-porous structure (for example, a simple plate material), the oil accumulated in the oil collecting portion 20a outside the cylindrical portion 23 is not easily returned to the inside of the cylindrical portion 23, which is preferable. In this case, the cylindrical portion 23 may be formed by combining different materials at the lower portion and the upper portion.

Fig. 12 is a schematic cross-sectional view of discharge space 20 in a modification of compressor 100 according to embodiment 1 of the present invention. The dashed arrows of fig. 12 show the main flow of oil.

As shown in fig. 12, the upper end of the cylindrical portion 23 is preferably spaced so as not to contact the upper container 1 a. The frame 4 and the cylindrical portion 23 are formed of metal or the like. Therefore, during operation of the compressor 100, the refrigerant is compressed in the compression chamber 9 and increases in temperature, and the refrigerant, oil, the fixed scroll 8, and the like in the discharge space 20 transfer heat to the frame 4 and the cylindrical portion 23 to increase the temperature, and the frame 4 and the cylindrical portion 23 thermally expand. At this time, if there is not a sufficient gap between the upper end of the cylindrical portion 23 and the upper container 1a, the upper end of the cylindrical portion 23 may contact the inner wall surface of the upper container 1a during expansion to generate stress, and thus the compressor 100 may be damaged. Therefore, if a sufficient gap is left so that the upper end of the cylindrical portion 23 does not contact the upper container 1a even if thermal expansion occurs, damage to the compressor 100 can be avoided.

Further, by providing the gap between the lower end of the cylindrical portion 23 and the upper surface of the frame 4, damage to the compressor 100 can be avoided. However, the refrigerant may be discharged to the oil collecting portion 20a from the gap between the lower end of the cylindrical portion 23 and the frame 4, and the oil collected in the lower portion of the oil collecting portion 20a may be blown off. Accordingly, the oil is less likely to collect in the oil return pipe 24 on the lower surface of the oil collecting portion 20a, and the amount of oil flowing from the oil collecting portion 20a to the oil reservoir 16 through the oil return pipe 24 is reduced, so that the oil is retained in the oil collecting portion 20 a.

When the oil is blown off as described above, the discharge space 20 is filled with oil droplets having a small diameter. The smaller the diameter of the oil droplets, the less likely the oil droplets receive the inertial force, and are not centrifugally separated even when returned to the inside of the cylindrical portion 23 through the plurality of holes 23a of the cylindrical portion 23, and therefore, the oil droplets are easily discharged from the discharge pipe 3 to the outside of the compressor 100 together with the refrigerant. Therefore, the gap is more preferably provided between the upper end of the cylindrical portion 23 and the upper container 1 a.

Embodiment mode 2

Embodiment 2 shows a structure in the vicinity of the discharge pipe 3. Hereinafter, the differences between embodiment 2 and embodiment 1 will be mainly described.

Fig. 13 is a schematic sectional view of the discharge space 20 in the compressor 101 according to embodiment 2 of the present invention. The dashed arrows of fig. 13 show the main oil flow.

As shown in fig. 13, in the compressor 101 according to embodiment 2, the end of the discharge pipe 3 protrudes from the inner wall surface of the upper container 1a toward the cylindrical portion 23. For example, the end of the discharge pipe 3 may be located below the upper end of the cylindrical portion 23.

Fig. 14 is a schematic cross-sectional view showing a comparative example in which the end of the discharge pipe 3 does not protrude toward the cylindrical portion 23. The solid arrows in fig. 14 show the main flow of refrigerant in the cross section, and the dashed arrows show the main flow of oil in the cross section.

As shown in fig. 14, the swirling flow of the refrigerant inside the cylindrical portion 23 flows toward the center of the cylindrical portion 23 as it goes toward the discharge pipe 3, and is discharged to the discharge pipe 3. Due to the centrifugal force of the swirling flow of the refrigerant immediately after being discharged from the swirling mechanism portion 22, the pressure in the vicinity of the inner wall surface of the cylindrical portion 23 on the swirling mechanism portion 22 side is higher than the pressure in the vicinity of the outer wall surface on the outer side of the cylindrical portion 23 on the opposite side separated by the cylindrical portion 23. Then, a part of the refrigerant flows from the inside of the cylindrical portion 23 to the outside through the plurality of holes 23 a. On the other hand, the swirling flow of the refrigerant flows toward the discharge pipe 3, and the swirling flow velocity of the refrigerant is reduced near the inner wall surface of the cylindrical portion 23 on the discharge pipe 3 side, and the centrifugal force is weakened. Therefore, the pressure in the vicinity of the inner wall surface of the cylindrical portion 23 on the discharge pipe 3 side is lower than the pressure in the vicinity of the outer wall surface of the outside of the cylindrical portion 23 on the opposite side separated by the cylindrical portion 23. Therefore, a part of the refrigerant flows from the outside of the cylindrical portion 23 to the inside of the cylindrical portion 23 via the plurality of holes 23a of the cylindrical portion 23 located on the swirl mechanism portion 22 side.

A pressure difference exists between a shearing force of a flow that draws a swirling flow of the refrigerant inside the cylindrical portion 23 flowing toward the discharge pipe 3 into the center of the inside of the cylindrical portion 23 and a pressure that flows the refrigerant from the outside to the inside on the wall surface of the cylindrical portion 23 on the discharge pipe 3 side. Therefore, due to this pressure difference, a flow of the refrigerant flowing from the discharge pipe 3 on the outer side to the inner side of the cylindrical portion 23 through the gap between the end portion of the cylindrical portion 23 on the discharge pipe 3 side and the upper container 1a is generated. When the shearing force of the refrigerant flow is applied, a part of the oil adhering to the inner wall surface of the upper tank 1a flows along the inner wall surface of the upper tank 1a from the outside of the cylindrical portion 23 toward the discharge pipe 3 inside, and is discharged from the discharge pipe 3 to the outside of the compressor.

Fig. 15 is a schematic cross-sectional view of the periphery of the discharge pipe 3 of the discharge space 20 in the compressor 101 according to embodiment 2 of the present invention shown in fig. 13. The solid-line arrows in fig. 15 show the main flow of refrigerant in the cross section, and the dashed-line arrows show the main flow of oil in the cross section.

As shown in fig. 15, in the compressor 101 according to embodiment 2, the end portion of the discharge pipe 3 protrudes downward from the upper end of the cylindrical portion 23. Thereby, the swirling flow of the refrigerant is drawn into the center inside the cylindrical portion 23 so as to be directed toward the discharge pipe 3, and the flow is separated from the end portion of the cylindrical portion 23 on the discharge pipe 3 side. Therefore, the flow rate of the oil flowing from the outer side of the cylindrical portion 23 to the inner side of the discharge pipe 3 along the inner wall surface of the upper container 1a decreases. Even if the oil flows toward the discharge pipe 3 along the inner wall surface of the upper container 1a, the oil collides with the outer wall surface of the discharge pipe 3 and is peeled off, and the amount of the oil reaching the discharge pipe 3 decreases.

As described above, the compressor 101 according to embodiment 2 can further reduce the amount of oil discharged to the outside of the compressor.

Fig. 16 is a schematic cross-sectional view of the discharge space 20 in a modification of the compressor 101 according to embodiment 2 of the present invention. The dashed arrows of fig. 16 show the main flow of oil.

As shown in fig. 16, a gap between the end of the cylindrical portion 23 on the discharge pipe 3 side and the upper container 1a may be closed with a flexible sealing material 28. The sealing material 28 is made of, for example, elastic rubber or resin. Since the sealing member 28 is flexible, the upper container 1a is not damaged by thermal expansion of the cylindrical portion 23.

Fig. 17 is a schematic cross-sectional view of the periphery of the discharge pipe 3 of the discharge space 20 in the modified example of the compressor 101 according to embodiment 2 of the present invention. The solid arrows in fig. 17 show the main flow of refrigerant in the cross section, and the dashed arrows show the main flow of oil in the cross section.

As shown in fig. 17, by closing the gap between the end portion of the cylindrical portion 23 on the discharge pipe 3 side and the upper container 1a with the sealing material 28, even if the oil outside the cylindrical portion 23 flows toward the cylindrical portion 23 along the inner wall surface of the upper container 1a, the oil can collide with the sealing material 28 and be peeled off. Therefore, the oil can be suppressed from reaching the discharge pipe 3.

As described above, the modification of embodiment 2 can further reduce the amount of oil discharged to the outside of the compressor.

Embodiment 3

In embodiment 3, the structure of the lower surface of the oil collecting portion 20a is shown. Hereinafter, the differences between embodiment 3 and embodiment 1 will be mainly described.

Fig. 18 is a schematic sectional view of the discharge space 20 in the compressor 102 according to embodiment 3 of the present invention. The double-line arrows in fig. 18 show the direction of gravity, and the dashed arrows show the main flow of oil.

As shown in fig. 18, in the compressor 102 according to embodiment 3, the end portion of the oil return pipe 24 on the oil collecting portion 20a side is separated from the cylindrical portion 23 and is disposed in the vicinity of the inner wall surface of the container 1. The upper surface of the frame 4 corresponding to the lower surface of the oil collecting portion 20a is configured to be lower in height from the cylindrical portion 23 side toward the inner wall surface side of the container 1.

In the vicinity of the outer wall surface of the cylindrical portion 23, the flow is accelerated by the oil discharged from the inside of the cylindrical portion 23 through the plurality of holes 23a and a part of the refrigerant. Due to this flow, oil on the upper surface of the frame 4 located near the outer wall surface of the cylindrical portion 23 is scattered, and the generated oil droplets having a small diameter may return to the inside of the cylindrical portion 23 through the plurality of holes 23 a.

In the compressor 102 according to embodiment 3, the height of the upper surface of the frame 4 is reduced from the cylindrical portion 23 side toward the inner wall surface side of the container 1, and the oil adhering to the upper surface of the frame 4 near the outer wall surface of the cylindrical portion 23 does not stay as it is, but flows toward the inner wall surface side of the container 1 due to gravity. This suppresses oil droplets having a small diameter, which are generated by scattering of oil on the upper surface of the frame 4 near the outer wall surface of the cylindrical portion 23, from returning to the inside of the cylindrical portion 23 through the plurality of holes 23a, and therefore the amount of oil discharged to the outside of the compressor is further reduced.

Fig. 19 is a schematic cross-sectional view of the discharge space 20 in a modification of the compressor 102 according to embodiment 3 of the present invention. The double-line arrows in fig. 19 show the direction of gravity, and the dashed arrows show the main flow of oil.

In the example shown in fig. 19, the end portion of the oil return pipe 24 on the oil collecting portion 20a side is separated from the cylindrical portion 23 and formed on the upper surface of the frame 4 in the vicinity of the inner wall surface of the container 1. The upper surface of the frame 4 corresponding to the lower surface of the oil collecting portion 20a is inclined so as to be lower toward the oil return pipe 24.

When the upper surface of the frame 4 corresponding to the lower surface of the oil collecting portion 20a is horizontal, oil is uniformly accumulated on the upper surface of the frame 4. Therefore, the oil accumulated on the upper surface of the frame 4 is scattered by the refrigerant airflow of the oil collector 20a, and the generated oil droplets having a small diameter may return to the inside of the cylindrical portion 23 through the plurality of holes 23 a. In particular, since the refrigerant gas and the oil flow faster near the outer wall surface of the cylindrical portion 23, the oil is easily scattered. In contrast, in the modification shown in fig. 19, the end of the oil collector 20a of the oil return pipe 24 is disposed near the inner wall surface of the container 1, and the upper surface of the frame 4 is inclined so as to be lower toward the oil return pipe 24. With this configuration, the oil adhered to the upper surface of the frame 4 does not stay as it is, but is collected toward the oil return pipe 24 by gravity and discharged to the suction space 19 via the oil return pipe 24. This suppresses oil droplets having a small diameter, which are generated by scattering of oil on the upper surface of the frame 4 near the outer wall surface of the cylindrical portion 23, from returning to the inside of the cylindrical portion 23 through the plurality of holes 23a, and thus the amount of oil discharged to the outside of the compressor is similarly further reduced.

Fig. 20 is a schematic sectional view of the discharge space 20 in the modified example of the compressor 102 according to embodiment 3 of the present invention. The double-line arrows in fig. 20 show the direction of gravity, and the dashed arrows show the main flow of oil.

In the example shown in fig. 20, a groove 4a is formed in the upper surface of the frame 4 corresponding to the lower surface of the oil collector 20a, and the end of the oil collector 20a on the oil return pipe 24 is formed at the bottom of the groove 4 a.

As shown in fig. 20, by forming the groove 4a in the upper surface of the frame 4, the oil adhering to the upper surface of the frame 4 collects in the groove 4a due to gravity and surface tension. Since the flow of the refrigerant gas in the space inside the groove 4a is slow, the oil collected in the groove 4a is less likely to scatter, and the oil droplets having a small diameter are prevented from being generated and returned to the inside of the cylindrical portion 23 through the plurality of holes 23 a. The oil collected in the groove 4a is discharged to the suction space 19 through the oil return pipe 24. This further reduces the amount of oil discharged to the outside of the compressor.

As shown in fig. 21, the groove 4a may be formed to surround the cylindrical portion 23. By forming the groove 4a so as to surround the cylindrical portion 23, the oil adhering to the upper surface of the frame 4 is easily collected uniformly in the groove 4 a. The groove 4a surrounding the cylindrical portion 23 may be formed in a circular shape as in the example shown in fig. 21, or may be formed in a polygonal shape. The groove 4a may be formed in a continuous shape so that the collected oil is collected to the oil return pipe 24.

Fig. 22 is a schematic cross-sectional view of the discharge space 20 in a modification of the compressor 102 according to embodiment 3 of the present invention. The double-line arrows in fig. 22 show the direction of gravity, and the dashed arrows show the main flow of oil.

As shown in fig. 22, the gap structure 25 may be disposed on the upper surface of the frame 4 corresponding to the lower surface of the oil collector 20a, and the end of the oil collector 20a of the oil return pipe 24 may be disposed below the gap structure 25. The void structure 25 has, for example, a porous (continuous porous) structure, a flocculent, a lattice structure, or a mesh structure. In the example of fig. 22, the void structure 25 is disposed inside the groove 4a formed in the upper surface of the frame 4, but the present invention is not limited to this.

By disposing the void structure 25 on the upper surface of the frame 4, the oil adhering to the upper surface of the frame 4 is captured by the void structure 25 due to the capillary force. The oil trapped in the void structure 25 is not easily scattered even by the shearing force of the refrigerant gas due to the capillary force, and the oil droplets having a small diameter are prevented from being generated and returned to the inside of the cylindrical portion 23 through the plurality of holes 23 a. The oil captured by the gap structure 25 is collected by gravity and capillary force toward the oil return pipe 24 located below the gap structure 25, and is discharged to the suction space 19 via the oil return pipe 24.

When solid foreign matter is mixed in the refrigerant or the oil, the solid foreign matter can be captured by the void structure 25. This prevents a problem that solid foreign matter is mixed into the oil flow path and the refrigerant flow path inside and outside the compressor due to the blockage of the oil return pipe 24.

The air gap structure 25 may be disposed on the upper surface of the frame 4 so as to surround the cylindrical portion 23. With this arrangement, the oil adhering to the upper surface of the frame 4 is easily collected uniformly in the gap structure 25. The gap structure 25 surrounding the cylindrical portion 23 may be formed in a circular shape or a polygonal shape. The gap structure 25 may be formed in a continuous shape so that the captured oil is collected in the oil return pipe 24.

As shown in fig. 22, by disposing the void structure 25 inside the groove 4a, oil is easily trapped by the void structure 25. Further, since the bottom of the air gap structure 25 is surrounded by the groove 4a, oil overflowing from the air gap structure 25 does not spread to the upper surface of the frame 4, and oil droplets having a small diameter are further prevented from being generated and returned to the inside of the cylindrical portion 23 through the plurality of holes 23 a.

Embodiment 4

In embodiment 4, the structure of the oil collecting portion 20a is shown. Hereinafter, the differences between embodiment 4 and embodiment 1 will be mainly described.

Fig. 23 is a schematic sectional view of the discharge space 20 in the compressor 103 according to embodiment 4 of the present invention. The double-line arrows in fig. 23 show the direction of gravity, and the dashed arrows show the main flow of oil. Fig. 24 is a perspective view of the inside of the discharge space 20 in the compressor 103 according to embodiment 4 of the present invention.

As shown in fig. 23 and 24, in the compressor 103 according to embodiment 4, the lateral baffle 26 is provided so as to divide the oil collecting portion 20a outside the cylindrical portion 23 into a plurality of spaces in the height direction of the cylindrical portion 23. The cross baffle 26 is provided below the plurality of holes 23a of the cylindrical portion 23. The cross baffle 26 may be connected to the outer wall surface of the cylindrical portion 23 or the inner wall surface of the container 1. The upper space partitioned by the cross baffle 26 can communicate with the inside of the cylindrical portion 23 through the plurality of holes 23a of the cylindrical portion 23, and the lower space can be a space connected to the suction space 19 through the oil return pipe 24. The transverse baffle 26 has a plurality of holes 26a, and the upper and lower spaces partitioned by the transverse baffle 26 are connected to each other via the plurality of holes 26 a.

By providing the cross baffle 26 so as to vertically separate the oil collecting portion 20a outside the cylindrical portion 23, the space below the cross baffle 26 is isolated from the refrigerant flow ejected from the plurality of holes 23a of the cylindrical portion 23. Therefore, the refrigerant flow in the space below the cross baffle 26 becomes gentle, and scattering of oil adhering to the upper surface of the frame 4 can be suppressed. Even if the oil adhered to the upper surface of the frame 4 is scattered, the oil droplets having a small diameter can be prevented from returning to the space above the cross baffle 26 and the space inside the cylindrical portion 23 by adhering the oil to the lower surface of the cross baffle 26. Therefore, the amount of oil discharged to the outside of the compressor can be further reduced.

Fig. 25 and 26 are schematic views of the flow of the refrigerant in the radial cross section of the cylindrical portion 23.

As shown in fig. 25, when the thickness of the cylindrical portion 23 is small and the width of the plurality of holes 23a is wide in the circumferential direction, the swirling flow of the refrigerant inside the cylindrical portion 23 is directly transmitted to the outside of the cylindrical portion 23 through the plurality of holes 23 a. Then, a swirling flow in the same direction as the swirling flow of the refrigerant inside the cylindrical portion 23 is generated at the outside of the cylindrical portion 23 at a slower speed than the swirling flow of the refrigerant.

On the other hand, as shown in fig. 26, when the thickness of the cylindrical portion 23 increases and the width of the plurality of holes 23a becomes narrower in the circumferential direction, the direction in which the swirling flow of the refrigerant inside the cylindrical portion 23 flows while flowing toward the outside of the cylindrical portion 23 through the plurality of holes 23a changes. Furthermore, a swirling flow in a direction opposite to the inside of the cylindrical portion 23 may be generated outside the cylindrical portion 23. Thus, a swirling flow in the same or opposite direction as the velocity of the refrigerant is slower than that in the inner side of the cylindrical portion 23 is generated outside the cylindrical portion 23. Since the cross baffle 26 is provided, even if a swirling flow of the refrigerant is generated in the space above the cross baffle 26, the swirling flow is further slowed down while flowing toward the space below the cross baffle 26 through the plurality of holes 26a of the cross baffle 26. Therefore, the shearing force of the oil adhering to the upper surface of the frame 4 from the swirling flow of the refrigerant is weakened, and the oil is not easily scattered.

The oil that flows out to the outside of the cylindrical portion 23 through the plurality of holes 23a by the centrifugal force generated by the swirling flow of the refrigerant inside the cylindrical portion 23 and flows out to the space above the transverse baffle 26 adheres to the upper surface of the transverse baffle 26 due to gravity. Immediately after adhering to the upper surface of the transverse baffle 26, the oil flows out to the space below the transverse baffle 26 through the plurality of holes 26a of the transverse baffle 26, and therefore scattering of the oil on the upper surface of the transverse baffle 26 is suppressed.

Further, at the time of starting the compressor, a large amount of oil that is taken up by a large amount of refrigerant liquid flowing from the suction pipe 2 due to rapid foaming of the refrigerant liquid stored in the oil reservoir 16 may enter the suction port 14 and flow into the centrifugal separation portion of the discharge space 20 through the compression chamber 9 and the discharge port 15.

A large amount of oil that has flowed into the centrifugal separation portion is discharged from the hole 23a to the oil collection portion 20a outside the cylindrical portion 23, but if the return oil to the oil reservoir 16 through the oil return pipe 24 cannot be kept up, the oil accumulates in the oil collection portion 20 a. Even in this case, when the oil level of the oil accumulated in the oil collecting portion 20a is positioned below the lateral baffle 26, the swirling flow of the refrigerant gas on the oil level is slowed, and therefore, the scattering of oil droplets having small diameters from the oil level is suppressed. Therefore, in embodiment 2, the amount of oil discharged to the outside of the compressor can be further reduced even when the compressor is started.

In the example shown in fig. 24, the transverse baffle 26 has a structure in which a plurality of circular holes 26a are provided in a hollow circular disk, but the plurality of holes 26a may have a long and narrow shape, or may have a porous (continuous porous), flocculent, lattice, mesh, or other void structure instead of the plurality of holes 26 a.

Fig. 27 is a schematic cross-sectional view of the discharge space 20 in a modification of the compressor 103 according to embodiment 4 of the present invention. The double-line arrows in fig. 27 show the direction of gravity, and the dashed arrows show the main flow of oil. Fig. 28 is a perspective view of the inside of the discharge space 20 in a modification of the compressor 103 according to embodiment 4 of the present invention.

As shown in fig. 27 and 28, a plurality of vertical baffle plates 27 may be provided so as to divide the oil collecting portion 20a outside the cylindrical portion 23 into a plurality of spaces in the circumferential direction of the cylindrical portion 23. The plurality of vertical baffles 27 may be connected to the outer wall surface of the cylindrical portion 23, the inner wall surface of the upper container 1a, or the upper surface of the frame 4.

By providing the plurality of vertical baffle plates 27 so as to be divided in the circumferential direction with the cylindrical portion 23 as the center, the swirling flow outside the cylindrical portion 23 as shown in fig. 25 and 26 is blocked by the vertical baffle plates 27, and the flow velocity is reduced. Accordingly, the shearing force of the oil adhering to the upper surface of the frame 4 from the swirling flow of the refrigerant is weakened, and the oil adhering to the upper surface of the frame 4 is less likely to scatter, so that the amount of oil discharged to the outside of the compressor is similarly further reduced.

A gap or slit may be provided below the longitudinal baffle 27 between the upper surface of the frame 4 and the inner wall surface of the container 1. In each of the spaces divided in the circumferential direction by the plurality of vertical baffles 27, the oil flowing out from the plurality of holes 23a of the cylindrical portion 23 is collected on the upper surface of the lower frame 4 by gravity. The oil collected on the upper surface of the frame 4 in each of the spaces divided by the plurality of vertical baffle plates 27 can be collected at the end of the oil collection portion 20a of the oil return pipe 24 by flowing into the spaces adjacent to each other in the circumferential direction through the gaps or slits provided below the plurality of vertical baffle plates 27.

Further, the transverse baffle 26 and the longitudinal baffle 27 may be provided in combination. This can simultaneously obtain the effects of the transverse baffle 26 and the longitudinal baffle 27.

Embodiment 5

Embodiment 5 shows a structure of the oil return flow path. Hereinafter, the differences between embodiment 5 and embodiment 1 will be mainly described.

Fig. 29 is a schematic cross-sectional view of an oil return flow path in the compressor 104 according to embodiment 5 of the present invention. The dashed arrows of fig. 23 show the main flow of oil.

In the example shown in fig. 29, a part of the oil return flow path for returning the oil from the discharge space 20 to the suction space 19 is formed by the oil return gap 4b provided in the frame 4. Namely, the following structure is provided: the frame 4 is provided with an oil return gap 4b, and one end of the oil return gap 4b is connected to the discharge space 20 and the other end thereof is connected to an oil return pipe 24. The flow rates of the refrigerant and the oil flowing from the discharge space 20 to the suction space 19 can be adjusted by the width of the internal flow path of the oil return gap 4b of the frame 4. The oil return gap 4b can be provided by forming a notch-shaped cutout on the side surface of the frame 4, for example.

In embodiment 5, by providing the oil return gap 4b, it is not necessary to adjust the flow rate of the refrigerant and the oil returning from the discharge space 20 to the suction space 19 by the diameter of the internal flow path of the oil return pipe 24, and therefore, the diameter of the oil return pipe 24 can be freely configured. For example, when the flow rates of the refrigerant and the oil returning from the discharge space 20 to the suction space 19 are adjusted by the diameter of the internal flow path of the oil return pipe 24, if the diameter of the oil return pipe 24 is reduced in order to reduce the flow rate of the refrigerant, the oil return pipe 24 is easily bent, and a trouble is easily caused at the time of manufacturing. If a part of the oil return flow path is formed by the oil return clearance 4b and the flow rate of the refrigerant and the oil returning from the discharge space 20 to the suction space 19 can be adjusted by the oil return clearance 4b, the oil return pipe 24 having a large diameter and being less likely to be bent can be used, and productivity can be improved.

Fig. 30 is a schematic cross-sectional view of the periphery of an oil return flow path in a modification of the compressor 104 according to embodiment 5 of the present invention. The dashed arrows of fig. 30 show the main flow of oil.

As shown in fig. 30, the oil return gap 4b of the frame 4 may be formed such that the width of the internal flow path repeats rapid contraction and rapid expansion. As shown in the example of fig. 29, when the width of the internal flow path of the oil return gap 4b of the frame 4 is constant, the flow rate of the refrigerant and the oil returning from the discharge space 20 to the suction space 19 is affected by the frictional resistance from the wall surface of the oil return gap 4 b. On the other hand, as shown in fig. 30, when the width of the internal flow path of the oil return gap 4b of the frame 4 is not constant and is formed so as to repeat rapid contraction and rapid expansion, the flow rate of the refrigerant and the oil returning from the discharge space 20 to the suction space 19 is affected by the inertial resistance caused by the rapid contraction and rapid expansion of the flow path. The frictional resistance has a strong influence on the viscosity of the fluid, and the inertial resistance has a strong influence on the velocity of the fluid.

Since a two-phase flow in which the flow rate of the refrigerant gas is small and the amount of the oil is large flows through the oil return gap 4b, the oil having a high viscosity is unlikely to flow when the influence of the frictional resistance is strong, and the refrigerant gas having a high flow velocity is unlikely to flow when the influence of the inertial resistance is strong. That is, when the influence of the inertial resistance is strong, the refrigerant gas does not easily flow, and the oil easily flows. By adjusting the width of the internal flow path in this manner so that the oil return gap 4b of the frame 4 repeats rapid contraction and rapid expansion, the following effects can be obtained. That is, under a wide range of operating conditions of the compressor, the flow rate of the refrigerant returning from the discharge space 20 to the suction space 19 can be reduced, and the oil can be returned to the suction space 19 so as to avoid the accumulation of the oil in the discharge space 20. Therefore, in the modification of embodiment 5, a compressor having a small amount of oil discharged to the outside of the compressor and having high compression efficiency and volume efficiency can be provided.

Embodiment 6

In embodiment 6, a compressor in which the electric mechanism unit 40 and the oil reservoir unit 16 are disposed on the discharge space 20 side is shown. Hereinafter, the differences between embodiment 6 and embodiment 1 will be mainly described.

Fig. 31 is a schematic cross-sectional view showing the structure of a compressor 105 according to embodiment 6 of the present invention. The double-line arrows in fig. 31 show the direction of gravity, and the dashed arrows show the main flow of oil.

As shown in fig. 31, the compressor 105 according to embodiment 6 has the following structure: the space corresponding to the suction space 19 of embodiment 1, the electric mechanism section 40 located in the space, and the oil reservoir 16 are located on the discharge space 20 side. That is, the suction pipe 2 is directly connected to the compression chamber 9, and the refrigerant flowing from the suction pipe 2 directly flows into the compression chamber 9. The refrigerant flowing in from the suction pipe 2 is compressed in the compression chamber 9, passes through the discharge port 15 and the check valve 21 in this order, and flows out to the centrifugal separation portion of the discharge space 20.

On the other hand, the oil in the oil reservoir 16 located in the discharge space 20 is sucked up from the oil supply pipe 17 due to the pressure difference between the high-pressure discharge space 20 and the refrigerant inflow side of the low-pressure compression chamber 9 or the connection portion with the suction pipe 2. The oil sucked up from the oil supply pipe 17 is supplied to the sliding portions such as the power conversion mechanism portion 6 through the oil supply line 13. Then, the oil supplied to the power conversion mechanism 6 flows into the compression chamber 9 from the refrigerant inflow side of the compression chamber 9 or the connection portion with the suction pipe 2, passes through the discharge hole 15 and the check valve 21 in order together with the refrigerant, and flows out to the centrifugal separation portion. In the example shown in fig. 31, since oil is drawn from the oil reservoir 16 by the pressure difference between the discharge space 20 and the refrigerant inflow side of the compression chamber 9, the oil pump 18 is not used, but the oil pump 18 may be used as an auxiliary for drawing oil and supplying the oil to each sliding portion.

The refrigerant and the oil that have flowed out to the centrifugal separation portion through the discharge hole 15 and the check valve 21 in this order become a swirling flow in the swirling mechanism portion 22, are separated into the refrigerant and the oil by the centrifugal force of the swirling flow in the cylindrical portion 23, and the refrigerant passes through the discharge pipe 3 and is discharged to the outside of the compressor. The separated oil is quickly discharged from the plurality of holes 23a of the cylindrical portion 23 to the oil collecting portion 20a outside the cylindrical portion 23. The oil discharged to the oil collecting portion 20a is collected by gravity on the upper surface of the frame 4 corresponding to the lower surface of the oil collecting portion 20a, and flows downward to the oil reservoir 16 through the gap 4b of the frame 4 serving as an oil return flow path. The gap 4b of the frame 4 serving as the oil return flow path does not need to be narrowed in width to reduce the flow rate of the refrigerant passing through the oil return flow path as in embodiment 5, and may be a flow path having a wide width so that the oil discharged to the oil collecting portion 20a smoothly falls down to the oil reservoir 16 by gravity.

According to the compressor 105 of embodiment 6, as in embodiment 1, the oil separated by the centrifugal force of the swirling flow in the centrifugal separation portion is quickly discharged to the oil collection portion 20a outside the cylindrical portion 23 through the plurality of holes 23a of the cylindrical portion 23. Therefore, the oil adhered to the inner wall of the cylindrical portion 23 is suppressed from being swirled up and scattered, and the amount of oil discharged to the outside of the compressor is reduced. As described above, in the present invention, even when the electric mechanism 40 and the oil reservoir 16 are located on the discharge space 20 side, the amount of oil discharged to the outside of the compressor can be reduced.

In the configuration shown in embodiment 1, the oil reservoir 16 is located on the suction space 19 side, and oil flows from the oil collector 20a located on the discharge space 20 side to the oil reservoir 16 located on the suction space 19 side due to the pressure difference between the discharge space 20 and the suction space 19. Therefore, a part of the refrigerant flows from the discharge space 20 to the suction space 19 through the oil return pipe 24 together with the oil. Therefore, the amount of the compressed refrigerant discharged to the outside of the compressor through the discharge pipe 3 is reduced, and the compressed high-temperature refrigerant flows into the low-temperature suction space 19. Therefore, the compression efficiency and the volumetric efficiency of the compressor may be reduced. In contrast, in the compressor 105 according to embodiment 6, the oil collector 20a and the oil reservoir 16 are both located on the discharge space 20 side, and it is not necessary to return the refrigerant from the discharge space 20 to the suction space side, and therefore, the compression efficiency and the volumetric efficiency are not reduced. Therefore, according to embodiment 6, a compressor having higher compression efficiency and volume efficiency can be provided.

Embodiment 7

Embodiment 7 shows a horizontal compressor in which the rotary shaft 5 is inclined with respect to the direction of gravity. Hereinafter, the differences between embodiment 7 and embodiment 1 will be mainly described.

Fig. 32 is a schematic sectional view showing the structure of a compressor 106 according to embodiment 7 of the present invention. The double-line arrows in fig. 1 show the direction of gravity, and the dashed arrows show the main oil flow.

As shown in fig. 32, the compressor 106 according to embodiment 7 is a horizontal compressor, and is disposed such that the rotary shaft 5 is inclined or horizontal with respect to the direction of gravity. The closer the inclination of the rotary shaft 5 to the direction of gravity is to the horizontal, the more the oil reservoir 16 is disposed on the side of the side container 1b of the lower container 1 by the action of gravity. Therefore, the oil supply pipe 17 has a structure in which the suction port 17a extends toward the oil reservoir 16 downward so as to be immersed in the oil reservoir 16. Further, since the oil discharged from the plurality of holes 23a of the cylindrical portion 23 to the oil collection portion 20a outside the cylindrical portion 23 is collected downward by gravity, the end portion of the oil return pipe 24 can be formed on the outer peripheral portion of the frame 4 located at the lowermost portion of the oil collection portion 20 a.

Similarly to the example shown in embodiment 1, the refrigerant and the oil that have flowed out to the centrifugal separation section through the discharge hole 15 and the check valve 21 in this order become a swirling flow in the swirling mechanism section 22, and the refrigerant and the oil are separated by the centrifugal force of the swirling flow in the cylindrical section 23. The refrigerant is discharged to the outside of the compressor through the discharge pipe 3, and the separated oil is discharged from the plurality of holes 23a of the cylindrical portion 23 to the oil collecting portion 20a outside the cylindrical portion 23. The oil discharged to the oil collecting portion 20a falls by gravity and flows directly downward in the oil collecting portion 20a, or adheres to the inner wall surface of the frame 4 or the upper container 1a and flows downward along the surface toward the oil collecting portion 20 a. The oil collected below the oil collecting portion 20a flows into the oil reservoir 16 through an oil return pipe 24 serving as an oil return flow path.

According to the compressor 106 of embodiment 7, as in embodiment 1, the oil separated by the centrifugal force of the swirling flow in the centrifugal separation portion is quickly discharged to the oil collection portion 20a outside the cylindrical portion 23 through the plurality of holes 23a of the cylindrical portion 23. Therefore, the oil adhered to the inner wall of the cylindrical portion 23 is suppressed from being swirled up and scattered, and the amount of oil discharged to the outside of the compressor is reduced. As described above, in the present invention, even in the case of the horizontal type compressor in which the rotary shaft 5 is inclined with respect to the gravity direction, the amount of oil discharged to the outside of the compressor can be reduced.

Further, according to the configuration of embodiment 7, the compressor 106 can be used while being inclined at a free angle to be horizontal to the direction of gravity in the direction in which the suction port 17a of the oil supply pipe 17 and the end of the oil trap 20a side of the oil return pipe 24 are located downward. The horizontal compressor can be installed in a low-height installation space where it is difficult to install the vertical compressor, and therefore, the application range of the compressor of the present invention can be expanded. Further, since the vertical compressor shown in embodiment 1 can be used as a horizontal compressor with substantially the same structure, it is not necessary to manufacture the vertical compressor and the horizontal compressor with different specifications, and the manufacturing facility and the manufacturing process of the compressor can be reduced.

Fig. 33 is a schematic cross-sectional view showing a modification of compressor 106 according to embodiment 7 of the present invention. The double-line arrows in fig. 1 show the direction of gravity, and the dashed arrows show the main flow of oil.

As shown in fig. 33, a modification of embodiment 7 is a horizontal compressor in which the electric mechanism unit 40 and the oil reservoir 16 are located on the discharge space 20 side as in embodiment 6. The closer the inclination of the rotary shaft 5 to the direction of gravity is to the horizontal, the more the oil reservoir 16 is disposed on the side of the side container 1b of the lower container 1 by the action of gravity. Therefore, the oil supply pipe 17 has a structure in which the suction port 17a extends toward the oil reservoir 16 downward so as to be immersed in the oil reservoir 16. Further, since the oil discharged from the plurality of holes 23a of the cylindrical portion 23 to the oil collecting portion 20a outside the cylindrical portion 23 is collected downward by gravity, the gap 4b of the frame 4 as the oil return flow path can be formed in the outer peripheral portion of the frame 4 positioned at the lowermost portion of the oil collecting portion 20 a.

In addition, although the embodiments 1 to 7 are described as different embodiments, the compressor may be configured by appropriately combining the characteristic configurations of the embodiments and the modifications. In each of embodiments 1 to 7, the modifications applied to the same components are also applied to other embodiments other than the embodiment described above.

In the above embodiments, the scroll compressor is described as an example, but the present invention can be applied to compressors other than the scroll type.

In the above embodiments, the example of the totally-enclosed compressor is described, but the present invention can be applied to a semi-enclosed or open type compressor.

Embodiment 8

Embodiment 8 shows a refrigeration cycle apparatus including the compressor according to any one of embodiments 1 to 7. Embodiment 8 will now be described by taking, as examples, a refrigeration cycle apparatus 200 including the compressor 100 of embodiment 1 and a refrigeration cycle apparatus 201 including the compressor 106 of embodiment 7.

The refrigeration cycle apparatus 200 includes the compressor 100, the first heat exchanger 51, the expansion device 52 including an expansion valve, a capillary tube, or the like, and the second heat exchanger 53 described in embodiment 1, and is configured to be connected to each other by a refrigerant pipe 54. The refrigeration cycle apparatus 200 includes a compressor chamber 55 that houses the compressor 100 according to embodiment 1, a first heat exchanger chamber 56 that houses the first heat exchanger 51, and a second heat exchanger chamber 57 that houses the second heat exchanger 53. Here, as shown in fig. 34, one frame body is divided into two to constitute a compressor chamber 55 and a first heat exchanger chamber 56, and the other frame body constitutes a second heat exchanger chamber 57. The method of configuring each chamber is not limited to this method, and one frame may be divided into three chambers, or each chamber may be configured by three frames.

The refrigeration cycle apparatus 200 may further include, as components, a first fan that promotes heat exchange in the first heat exchanger 51, a second fan that promotes heat exchange in the second heat exchanger 53, and a four-way valve that switches the connection of the refrigerant pipe 54 in the case of cold-hot switching. However, these components are not described in fig. 34. The refrigeration cycle apparatus 200 includes a control device 58 that controls each component. The control device 58 may be housed in or disposed adjacent to any one of the compressor room 55, the first heat exchanger room 56, and the second heat exchanger room 57, but may be independently disposed for interlocking control with external equipment.

Fig. 35 shows a schematic diagram of a refrigeration cycle apparatus equipped with a conventional compressor as a comparative example. The same components as those of the refrigeration cycle apparatus 200 will not be described.

As shown in fig. 35, a refrigeration cycle apparatus equipped with a conventional compressor includes an oil separator 70, an oil return pipe 71, and an oil return valve 72 to prevent oil discharged from the compressor from flowing to the first heat exchanger 51 and the second heat exchanger 53 and causing oil in the compressor to be depleted. The refrigerant and the oil discharged from the compressor are separated by the oil separator 70, and the oil flows to the compressor suction side through the oil return pipe 71.

The oil return valve 72 is opened and closed under the control of the control device 58, and is closed during normal operation, but is opened during startup in order to temporarily increase the amount of oil returning from the oil separator to the compressor suction side. When the refrigeration cycle apparatus is stopped, the refrigerant inside is liquefied, and the refrigerant liquid is accumulated inside the compressor and the oil separator. Therefore, at the time of startup, a large amount of oil is discharged from the compressor due to foaming of the refrigerant inside the compressor, etc., and a large amount of oil flows into the oil separator 70. When the refrigerant and the oil temporarily accumulate inside the oil separator, the oil separation efficiency decreases, the oil flows into the first heat exchanger 51 and the second heat exchanger 53, and the oil inside the compressor is depleted. In order to prevent this, control is performed to open the oil return valve 72 at the time of startup so as to temporarily increase the amount of oil returning from the oil separator to the compressor suction side.

As described above, the refrigeration cycle apparatus having the conventional compressor mounted thereon requires components such as the oil separator 70, the oil return pipe 71, the oil return valve 72, the space of the compressor room 55 in which these are housed, and the control of the oil return valve 72 by the control device 58. The conventional oil separator 70 has a low oil separation efficiency, and the oil separator 70 is installed outside the compressor because the height of the oil separator needs to be increased in order to sufficiently separate oil from the refrigerant.

In contrast, in the refrigeration cycle apparatus 200 including the compressor 100 according to embodiment 8, the amount of oil discharged to the outside of the compressor can be sufficiently reduced by the small-sized oil separator provided inside the compressor 100, and therefore, the above-described components are not required. Therefore, the refrigeration cycle apparatus 200 including the compressor 100 according to embodiment 8 has fewer components than a refrigeration cycle apparatus including a conventional compressor, can improve productivity, and can be downsized and mounted in a narrow installation space. Further, the refrigeration cycle apparatus 200 eliminates the possibility of malfunction or malfunction of the oil return valve 72 or the function of the control device 58 for controlling the oil return valve 72, thereby ensuring a longer product life.

Fig. 36 is a schematic diagram of the refrigeration cycle apparatus 201 according to embodiment 8. The same components as those of the refrigeration cycle apparatus 200 will not be described.

The refrigeration cycle apparatus 201 includes the horizontal compressor 106 described in embodiment 7. As described above, the compressor 106 is provided in the compressor chamber 55 such that the rotary shaft 5 is inclined with respect to the gravitational direction. In the compressor 100, as shown in fig. 1, the compression mechanism section 30 and the electric mechanism section 40 are arranged in a row on the rotary shaft 5, and therefore have an outer shape elongated in the direction of the rotary shaft 5. Therefore, as shown in fig. 34, when the compressor 100 is installed so that the rotation shaft 5 is parallel to the gravitational direction, the height of the installation space required for installing the compressor 100 becomes high. However, as shown in fig. 36, in the refrigeration cycle apparatus 201 according to embodiment 8, the compressor 106 is disposed so as to be horizontally disposed, and therefore, the height of the installation space can be reduced. The height of the installation space can be reduced as the rotation axis 5 is inclined in the vertical direction with respect to the gravity direction.

Fig. 37 shows a schematic diagram of a refrigeration cycle apparatus mounted with a conventional horizontal compressor as a comparative example. The same components as those of the refrigeration cycle apparatus 201 will not be described.

The refrigeration cycle apparatus equipped with the conventional horizontal compressor shown in fig. 37 requires the same components as those of the comparative example of the refrigeration cycle apparatus equipped with the conventional vertical compressor shown in fig. 35. That is, the refrigeration cycle apparatus mounted with the conventional horizontal compressor shown in fig. 37 requires a space for the oil separator 70, the oil return pipe 71, the oil return valve 72, and the compressor room 55 for housing them. This is to prevent oil discharged from the compressor from flowing into the first heat exchanger 51 and the second heat exchanger 53 and thereby to prevent oil in the compressor from being exhausted. The refrigeration cycle apparatus mounted with the conventional horizontal compressor shown in fig. 37 also requires control of the oil return valve 72 by the control device 58. As shown in fig. 37, when the height of the compressor chamber 55 is limited due to the installation space, the oil separator 70 is lowered in height, and therefore the oil separation efficiency is lowered, and there is a possibility that oil cannot be sufficiently separated from the refrigerant discharged to the outside of the compressor.

In contrast, in the refrigeration cycle apparatus 201 including the horizontal compressor 106 according to embodiment 8, the amount of oil discharged to the outside of the compressor can be sufficiently reduced by the small-sized oil separator provided inside the compressor, and therefore, the above-described components are not required. In addition, even when the height of the installation space is limited, the amount of oil discharged to the outside of the compressor can be sufficiently reduced.

Therefore, the refrigeration cycle apparatus 201 including the compressor 106 according to embodiment 8 has fewer components, can improve productivity, and can be downsized and mounted in a small installation space. Further, the refrigeration cycle apparatus 201 eliminates the possibility of malfunction or malfunction of the oil return valve 72 or the function of the control device 58 for controlling the oil return valve 72, thereby ensuring a longer product life. In addition, even when the height of the installation space is limited, the amount of oil discharged to the outside of the compressor can be sufficiently reduced.

Embodiment 9

In embodiment 9, a compressor is shown in which a refrigerant circulating flow is further generated to cool the electric mechanism unit 40 in embodiment 6 in which the electric mechanism unit 40 and the oil reservoir 16 are disposed on the discharge space 20 side. Hereinafter, the differences between embodiment 9 and embodiment 6 will be mainly described.

Fig. 38 is a schematic cross-sectional view showing the structure of a compressor 107 according to embodiment 9 of the present invention. The double-line arrows in fig. 38 show the direction of gravity, and the solid-line arrows show the main flow of refrigerant.

As shown in fig. 38, the compressor 107 according to embodiment 9 has the following configuration: the discharge space 20 of embodiment 6 is also provided therein with a fan 81 attached to the rotary shaft 5 to cool the electric mechanism unit 40, a partition 82, and a flow path 4c formed in the frame 4. In fig. 38, the flow path 4c is illustrated by a broken line in the frame 4 portion. The partition 82 guides a refrigerant circulating flow generated by the fan 81 by the rotation of the rotary shaft 5 to the rotor cooling passage 11a provided to penetrate the rotor 11 in the axial direction and the stator cooling passage 12a provided to penetrate the stator 12 in the axial direction.

In embodiment 6, the gap 4b is used as the oil return flow path, but in embodiment 9, including a modification described later, the gap may not be used as the oil return flow path. However, the "gap 4 b" in embodiment 6 is structurally the same as the "gap 4 b" in embodiment 9, and therefore the same reference numeral is used in embodiment 9 to designate the "gap 4 b". The gap 4b and the flow path 4c are flow paths provided between the compression mechanism section 30 and the container 1, and both flow paths have one end communicating with the oil collecting section 20a and the other end communicating with a space between the compression mechanism section 30 and the electric mechanism section 40.

In the example shown in fig. 38, the fan 81 is partially connected to the rotary shaft 5 between the rotor 11 and the frame 4. The spacer 82 is formed in a ring shape as viewed in the direction of the rotation shaft 5. The partition 82 is provided to partition a space between the electric mechanism section 40 and the frame 4 into an inner space 83a having the fan 81 and communicating with the rotor cooling path 11a and the gap 4b, and an outer space 83b communicating with the stator cooling path 12a and the flow path 4 c.

In this configuration, as shown by solid arrows in fig. 38, the refrigerant circulating flow generated by the fan 81 flows through the gap 4b, the oil collector 20a, the flow path 4c, the stator cooling path 12a, the rotor cooling path 11a, and the fan 81 in this order. When the refrigerant circulating flow flows through the oil collector 20a, heat is transferred to the swirling refrigerant flow flowing inside the cylindrical portion 23 via the cylindrical portion 23. The refrigerant circulating flow radiates heat to the outside of the container 1 through the upper container 1a and the side container 1b by convective heat transfer. The refrigerant of the refrigerant circulation flow whose temperature is lowered by the heat radiation receives heat from the stator 12 when flowing in the stator cooling path 12a, and receives heat from the rotor 11 when flowing in the rotor cooling path 11a, whereby the electric mechanism portion 40 is cooled.

The oil discharged from the inner passage holes 23a of the cylindrical portion 23 to the outer oil collection portion 20a merges with the refrigerant circulating flow flowing through the oil collection portion 20a, flows through the flow passage 4c and the stator cooling passage 12a, and then mostly flows down to the oil reservoir 16.

The outlet of the gap 4b of the frame 4 may be arranged at the upper side in the oil collecting portion 20a so as to prevent the oil adhering to the upper tank 1a or the side tank 1b from rising along the wall surface and returning to the cylindrical portion 23. In this example, the partition plate 84 extending from the gap 4b of the frame 4 toward the oil collecting portion 20a is provided, and the outlet of the gap 4b is arranged on the upper side in the oil collecting portion 20 a. The refrigerant flowing out of the outlet of the gap 4b may flow downward to the flow path 4c in the vicinity of the wall surface of the upper tank 1a or the side tank 1b in the oil collecting portion 20 a. In the configuration of fig. 38, the refrigerant that has swirled through the rotor cooling path 11a flows into the fan 81, and therefore the fan 81 may be of a centrifugal type.

Fig. 39 is a schematic cross-sectional view showing a modification of compressor 107 according to embodiment 9 of the present invention. The double-line arrows in fig. 39 show the direction of gravity, and the solid-line arrows show the main flow of refrigerant.

Fig. 39 reverses the direction of the refrigerant circulating flow generated by the fan 81 to fig. 38. In fig. 38, the partition plate 84 is provided on the gap 4b side, but in this modification, it is provided on the flow path 4c side. The other structure is the same as that of fig. 38.

In this configuration, as shown by solid arrows in fig. 39, the refrigerant circulating flow generated by the fan 81 flows through the rotor cooling path 11a, the stator cooling path 12a, the flow path 4c, the oil collector 20a, the gap 4b, and the fan 81 in this order.

In the configuration of fig. 39, the refrigerant flows in the rotor cooling path 11a by the fan 81, and therefore, the fan 81 may be of an axial flow type.

Fig. 40 is a schematic cross-sectional view showing a modification of compressor 107 according to embodiment 9 of the present invention. The double-line arrows in fig. 40 show the direction of gravity, and the solid-line arrows show the main flow of refrigerant.

The position of the fan 81 in fig. 40 is different from that in fig. 38. Specifically, the fan 81 is partially connected to the rotating shaft 5 between the rotor 11 and the sub-frame 10. That is, the position of the fan 81 may be set to the upper side of the electric mechanism 40 as shown in fig. 38, or may be set to the lower side of the electric mechanism 40 as shown in fig. 40. In short, the fan 81 may be disposed on one side or the other side of the rotation shaft 5 in the axial direction of the electric mechanism 40 so as to face the electric mechanism 40. In fig. 40, the configuration other than the arrangement of the fan 81 is the same as that in fig. 38.

In this configuration, as shown by solid arrows in fig. 40, the refrigerant circulating flow generated by the fan 81 flows through the rotor cooling passage 11a, the gap 4b, the oil collecting portion 20a, the flow passage 4c, the stator cooling passage 12a, and the fan 81 in this order.

In the configuration of fig. 40, the refrigerant flows in the rotor cooling path 11a by the fan 81, and therefore, the fan 81 may be of an axial flow type.

Fig. 41 is a schematic cross-sectional view showing a modification of compressor 107 according to embodiment 9 of the present invention. The double-line arrows in fig. 41 show the direction of gravity, and the solid-line arrows show the main flow of refrigerant.

Fig. 41 reverses the direction of the refrigerant circulating flow generated by the fan 81 to fig. 38. The position of the fan 81 is different from that in fig. 38. Specifically, the fan 81 is partially connected to the rotating shaft 5 between the rotor 11 and the sub-frame 10. The other structure is the same as that of fig. 38.

In this configuration, as shown by solid arrows in fig. 41, the refrigerant circulating flow generated by the fan 81 flows through the stator cooling passage 12a, the flow passage 4c, the oil collecting portion 20a, the gap 4b, the rotor cooling passage 11a, and the fan 81 in this order.

In the configuration of fig. 41, the refrigerant that has swirled through the rotor cooling path 11a flows into the fan 81, and therefore the fan 81 may be of a centrifugal type.

With the configuration shown in fig. 38 to 41, even in the compressor in which the electric mechanism unit 40 is located on the discharge space 20 side and the temperature is likely to increase as in embodiment 6, the amount of oil discharged to the outside of the compressor can be reduced and the temperature increase of the electric mechanism unit 40 can be suppressed. By suppressing the temperature rise of the electric mechanism portion 40, the motor efficiency is improved, the compressor efficiency is increased, the usable temperature conditions are widened, and the possibility of occurrence of a trouble due to an excess temperature can be reduced. The compressor shown in fig. 38 to 41 can be applied to the refrigeration cycle apparatus shown in fig. 34 to 37.

Description of the reference numerals

1, container; 1a an upper container; 1b a side container; 1c a lower container; 2a suction pipe; 3a discharge piping; 4, a frame; 4a groove; 4b a gap; 4c a flow path; 5 rotating the shaft; 6a power conversion mechanism part; 7 oscillating scroll; 7a wrap; 8, fixing the scroll; 8a wrap; 9 a compression chamber; 10 sub-frames; 11a rotor; 12a stator; 13 oil supply line; 14 a suction hole; 15 discharge holes; 16 an oil reservoir; 16a oil level; 17 an oil supply pipe; 17a suction port; 18 an oil pump; 19 a suction space; 20a discharge space; 20a an oil collecting part; 21 a check valve; 22a revolving mechanism part; 22a flow path; 22b a circular disk; 22c a blade; 22d, cutting; 22e a spiral plate; 23a cylindrical part; 23a holes; 23b a void structure; 24 an oil return pipe; 25 void structures; 26 transverse baffle plates; 26a holes; 27 longitudinal baffle plates; 28 sealing material; 30 a compression mechanism part; 40 electric mechanism part; 51 a first heat exchanger; 52 a throttling device; 53 a second heat exchanger; 54 a refrigerant pipe; 55 a compressor chamber; 56 a first heat exchanger chamber; 57 a second heat exchanger chamber; 58 control device; 70 an oil separator; 71 an oil return pipe; 72 an oil return valve; 81 fans; 82 a separator; 83a inside space; 83b outside space; 84 a partition plate; 100. 101, 102, 103, 104, 105, 106, 107 compressors; 200. 201 refrigeration cycle device.

Claims

1. A compressor is provided with:

a container having an oil reservoir;

the centrifugal separation part comprises:

2. The compressor of claim 1,

the lower end of the cylindrical part is connected with the lower surface of the oil collecting part without a gap,

the hole is not formed in a lower region of the side surface of the cylindrical portion adjacent to the lower end of the cylindrical portion.

3. The compressor of claim 1 or 2,

the hole is not formed in a region of the side surface of the cylindrical portion that is at the same height as the outlet of the swirl mechanism portion.

4. The compressor according to any one of claims 1 to 3,

an opening ratio of a region having the hole in the side surface of the cylindrical portion is less than 50%.

5. The compressor according to any one of claims 1 to 4,

the hole on the side surface of the cylindrical portion has an elongated shape arranged such that the long side of the hole intersects the direction of the swirling flow on the inner wall surface of the cylindrical portion.

6. The compressor according to any one of claims 1 to 5,

an end portion of the discharge pipe protrudes from an inner wall surface of the container toward the cylindrical portion.

7. The compressor of any one of claims 1 to 6,

a flexible sealing material is provided between the inner wall of the container and the upper end of the cylindrical portion.

8. The compressor according to any one of claims 1 to 7,

the oil collection device is provided with an oil return flow path for allowing the oil collected in the oil collection portion to flow to the oil storage portion.

9. The compressor of claim 8,

the oil return flow path is disposed away from the cylindrical portion,

the lower surface of the oil collecting portion is formed so as to be inclined downward toward the oil return flow path.

10. The compressor of claim 9,

the lower surface of the oil collecting portion is formed so as to be inclined downward from the outer circumferential surface side of the cylindrical portion toward the inner wall surface side of the container.

11. The compressor of any one of claims 8 to 10,

the lower surface of the oil collecting part is provided with a groove, and the bottom of the groove is provided with the oil return flow path.

12. The compressor of any one of claims 8 to 11,

a gap structure is provided on a lower surface of the oil collecting portion, and the oil return flow path is provided below the gap structure.

13. The compressor of any one of claims 8 to 12,

a part of the oil return flow path is formed by a gap provided between a frame that fixes the compression mechanism section to the container and an inner wall surface of the container.

14. The compressor of any one of claims 1 to 13,

a transverse baffle plate is provided to divide the oil collecting portion into a plurality of spaces in the height direction of the cylindrical portion.

15. The compressor of any one of claims 1 to 14,

the oil collecting portion is provided with a longitudinal baffle plate dividing the oil collecting portion into a plurality of spaces in the circumferential direction of the cylindrical portion.

16. The compressor according to any one of claims 1 to 15, wherein:

an electric mechanism unit that drives the compression mechanism unit;

a rotating shaft connecting the compression mechanism unit and the electric mechanism unit; and

and a fan provided on the rotating shaft and cooling the electric mechanism.

17. The compressor of claim 16,

the fan is disposed on the rotating shaft on one side or the other side in the axial direction of the electric mechanism portion so as to face the electric mechanism portion,

the refrigerant circulating flow generated by the driving of the fan passes through a cooling passage formed to penetrate the electric mechanism portion in the axial direction, and the electric mechanism portion is cooled.

18. The compressor of claim 17,

the electric mechanism portion includes a rotor attached to the rotating shaft and a stator disposed so as to cover an outer periphery of the rotor,

the cooling passage is constituted by a rotor cooling passage formed in the rotor and a stator cooling passage formed in the stator,

two flow paths are formed between the compression mechanism portion and the container, one ends of the two flow paths communicate with the oil collecting portion, and the other ends communicate with a space between the compression mechanism portion and the electric mechanism portion,

a space between the compression mechanism unit and the electric mechanism unit is partitioned by a partition plate into an inner space and an outer space, the inner space communicating with one of the two flow paths and the rotor cooling path, the outer space communicating with the other of the two flow paths and the stator cooling path,

the refrigerant circulating flow circulates in the inner space, one of the two flow paths, the oil collecting portion, the other of the two flow paths, the stator cooling path, and the rotor cooling path in this order or in a reverse order.

19. A refrigeration cycle device is provided with: the compressor according to any one of claims 1 to 18, a first heat exchanger connected to the compressor, an expansion device connected to the first heat exchanger, a second heat exchanger connected to the expansion device, a compressor connected to the second heat exchanger, and refrigerant piping connecting these.