WO2023089750A1

WO2023089750A1 - Compressor and refrigeration cycle device using same

Info

Publication number: WO2023089750A1
Application number: PCT/JP2021/042513
Authority: WO
Inventors: 尚孝黒田; 浩平達脇
Original assignee: 三菱電機株式会社
Priority date: 2021-11-19
Filing date: 2021-11-19
Publication date: 2023-05-25

Abstract

This compressor is provided with: a container having an oil storage unit; a suction pipe that sucks a refrigerant from the outside of the container; a compression mechanism unit that is arranged inside the container and compresses the refrigerant having been sucked by the suction pipe; a frame that fixes the compression mechanism unit to the container; an oil separation unit that separates oil from the refrigerant having been compressed by the compression mechanism unit; an ejection pipe that ejects the refrigerant having passed through the oil separation unit to the outside from above the container; an oil collection unit that is provided outside the oil separation unit and collects the oil having been discharged from the oil separation unit; a depressurization unit that constitutes an oil return flow path to return the oil having been collected by the oil collection unit to the oil storage unit; and an oil return unit that constitutes the oil return flow path, is provided so as to extend from an exit side of the depressurization unit toward the oil storage unit, and returns the oil having passed through the depressurization unit to the oil storage unit. The depressurization unit increases a pressure loss of the oil having been collected by the oil collection unit.

Description

Compressor and refrigeration cycle device provided with the same

The present disclosure relates to a compressor and a refrigeration cycle device including the same.

　In conventional compressors, the oil that lubricates the sliding parts of the compressor may be discharged from the discharge pipe to the outside of the compressor together with the compressed refrigerant. If oil continues to be discharged from the compressor in this way, the amount of oil stored in the oil reservoir continues to decrease, and the oil supplied to the sliding parts may be depleted, resulting in insufficient lubrication. Therefore, a compressor has been proposed in which the refrigerant compressed in the compression chamber and the oil are separated, and the separated oil is returned to the oil reservoir to suppress the reduction of the oil in the oil reservoir (see, for example, Patent Document 1). .

In Patent Document 1, refrigerant compressed in a compression mechanism section is swirled in a centrifugal separation section, oil is separated from the refrigerant by the centrifugal force of the swirling flow, and the separated oil is sent from a return flow path formed by a gap of a frame to an oil storage section. is reverting to

Japanese Patent No. 6573743

However, in Patent Document 1, since the centrifugal separation section is a high-pressure space and the oil storage section is a low-pressure space, the high-pressure, high-temperature oil from the centrifugal separation section is returned to the oil storage section as it is. There is a problem that the reliability is lowered.

The present disclosure has been made to solve the above problems, and aims to provide a compressor and a refrigeration cycle device including the same that can suppress deterioration in reliability.

A compressor according to the present disclosure includes a container having an oil reservoir, a suction pipe that sucks refrigerant from the outside of the container, and a compression mechanism that is arranged inside the container and compresses the refrigerant sucked by the suction pipe. a frame for fixing the compression mechanism to the container; an oil separation unit for separating oil from the refrigerant compressed by the compression mechanism; an oil collection section provided outside the oil separation section for collecting the oil discharged from the oil separation section; and a return oil flow for returning the oil collected in the oil collection section to the oil storage section. and a decompression section constituting a path, and the oil return flow path, which is provided so as to extend from the outlet side of the decompression section toward the oil storage section, and the oil after passing through the decompression section is returned to the oil storage section. and an oil return section for returning, wherein the decompression section increases the pressure loss of the oil collected in the oil collecting section.

A refrigeration cycle device according to the present disclosure has a refrigerant circuit in which the compressor, condenser, expansion device, and evaporator are connected by pipes and in which refrigerant circulates.

According to the compressor according to the present disclosure and the refrigeration cycle device including the same, the pressure reducing section that configures the oil return flow path for returning the oil collected in the oil collection section to the oil storage section is provided. Thus, by providing the pressure reduction section in the oil return passage for returning the oil collected in the oil collection section to the oil storage section, the pressure loss of the oil increases when passing through the pressure reduction section. Since the pressure loss increases and the oil collected in the oil collection section can be decompressed and cooled, the high-pressure, high-temperature oil collected in the oil collection section is not returned to the oil storage section as it is. A decrease in reliability can be suppressed.

1 is a schematic cross-sectional view showing the configuration of a compressor according to Embodiment 1; FIG. 4 is a perspective view of a turning mechanism part in the centrifugal separation part of the compressor according to Embodiment 1. FIG. 4 is a perspective view of a cylindrical portion in the centrifugal separation section of the compressor according to Embodiment 1. FIG. 3 is a cross-sectional view of the helical passage screw, the oil return pipe, and the periphery thereof of the compressor according to Embodiment 1. FIG. It is a cross-sectional schematic diagram of an internally grooved copper tube. FIG. 6 is a schematic cross-sectional view showing the configuration of a compressor according to Embodiment 2; FIG. 10 is a diagram showing a configuration example of a refrigeration cycle apparatus according to Embodiment 3;

A compressor and a refrigeration cycle device according to an embodiment will be described below with reference to the drawings. Here, in the following drawings including FIG. 1, the same reference numerals denote the same or equivalent parts, and are common throughout the embodiments described below. The forms of the constituent elements shown in the entire specification are merely examples, and are not limited to the forms described in the specification. In addition, in the following drawings including FIG. 1, the dimensional relationship, shape, etc. of each constituent member may differ from the actual one.

Embodiment 1.
FIG. 1 is a schematic cross-sectional view showing the configuration of a compressor 101 according to Embodiment 1. FIG. The double-lined arrow in FIG. 1 indicates the direction of gravity, and the dotted-lined arrow indicates the main flow of oil.

Compressor 101 according to Embodiment 1 is one of the components of a refrigeration cycle device used for applications such as air conditioners, refrigeration devices, refrigerators, freezers, vending machines, and water heaters. . Further, the compressor 101 according to Embodiment 1 is a scroll compressor.

The structure of the compressor 101 according to Embodiment 1 will be described below.
As shown in FIG. 1, the compressor 101 according to Embodiment 1 includes a compression mechanism portion 30 that compresses refrigerant, an electric mechanism portion 40 that drives the compression mechanism portion 30, and a rotational driving force of the electric mechanism portion 40. A rotating shaft 5 that receives and transmits the power to the compression mechanism section 30 , and a container 1 that houses the compression mechanism section 30 and the electric mechanism section 40 are provided. A frame 4 for fixing the compression mechanism 30 to the container 1 is further provided in the container 1 between the compression mechanism 30 and the electric mechanism 40 . As the refrigerant compressed by the compressor 101, an HFC-based refrigerant, an HC-based refrigerant, or a natural refrigerant is used. Since these refrigerants have a low global warming potential (GWP), they can reduce the impact on global warming.

The compression mechanism section 30 has a power conversion mechanism section 6 , an orbiting scroll 7 that is attached to the power conversion mechanism section 6 and performs an oscillating motion, and a fixed scroll 8 . The power conversion mechanism section 6 is a mechanism that is attached to the rotary shaft 5 that is rotationally driven by the electric mechanism section 40 and converts rotational driving force into compression driving force. A spiral wrap 7 a is formed on one surface of the orbiting scroll 7 , and a spiral wrap 8 a is formed on one surface of the fixed scroll 8 . The orbiting scroll 7 and the fixed scroll 8 are combined so that the

spiral wraps

7a, 8a are meshed with each other. Thereby, a plurality of compression chambers 9 separated from each other by the spiral wrap 7a or the spiral wrap 8a are formed between the orbiting scroll 7 and the fixed scroll 8 .

The rotating shaft 5 has one end rotatably supported by the frame 4 and the power conversion mechanism 6 and the other end rotatably supported by the sub-frame 10 . A subframe 10 is fixed to the container 1 . In FIG. 1, illustration of detailed connection structures and positions of the rotation shaft 5, the frame 4, and the power conversion mechanism 6 is omitted. Further, in FIG. 1, illustration of the detailed connection structure and position between the rotating shaft 5 and the subframe 10 is omitted.

A rotor 11 of the electric mechanism section 40 is attached to a portion between one end and the other end of the rotating shaft 5 . The stator 12 of the electric mechanism section 40 is arranged so as to cover the outer circumference of the rotor 11 , and the stator 12 is fixed to the container 1 .

The container 1 is constructed by connecting three parts: a bottomed cylindrical upper container 1a, a cylindrical side container 1b, and a bottomed cylindrical lower container 1c. A suction pipe 2 for sucking low-pressure refrigerant from outside the compressor 101 is attached to the side container 1b, and a discharge pipe 3 for discharging compressed high-pressure refrigerant to the outside of the compressor 101 is attached to the upper container 1a. . The internal space of the container 1 is divided into a suction space 19 on the side of the suction pipe 2 and a discharge space 20 on the side of the discharge pipe 3 by the compression mechanism portion 30 and the frame 4, and the electric mechanism portion 40 is arranged in the suction space 19. there is That is, the suction space 19 is filled with the low-pressure refrigerant sucked from the suction pipe 2 and becomes a low-pressure space. Also, the discharge space 20 is filled with the high-pressure refrigerant compressed by the compression mechanism portion 30 to form a high-pressure space. In addition, in the internal space of the container 1 , the space between the suction space 19 and the discharge space 20 is called a compression space 25 .

The bottom of the container 1 is provided with an oil reservoir 16 for storing oil. An oil pump 18 for pumping up the oil accumulated in the oil reservoir 16 is provided at the end of the rotary shaft 5 on the subframe 10 side. An oil supply pipe 17 extending toward the oil reservoir 16 is connected to the oil pump 18 , and a suction port 17 a formed at the tip of the oil supply pipe 17 is immersed in the oil in the oil reservoir 16 . Then, the oil pump 18 pumps up the oil accumulated in the oil reservoir 16 through the oil supply pipe 17, and through the oil supply pipe 13 formed inside the rotating shaft 5, each sliding part in the compressor 101, for example, Oil is supplied to the power conversion mechanism 6 and the like.

It should be noted that the oil level height position of the oil reservoir 16 changes depending on the operating environment or operating conditions of the compressor 101 . Therefore, in order to ensure that the supply of oil to each sliding portion in the compressor 101 is not interrupted, the height position of the suction port 17a is adjusted so that the suction port 17a is immersed in oil under all conditions. In Embodiment 1, the oil pump 18 is provided at the end of the rotating shaft 5 on the sub-frame 10 side, but is not limited thereto, and may be provided at the end of the rotating shaft 5 on the frame 4 side. good. Moreover, as the oil pump 18, pumps having various structures can be used.

The frame 4 is provided with a suction hole 14 that serves as a flow path for the refrigerant to flow from the suction space 19 to the compression chamber 9 . The frame 4 and the fixed scroll 8 are provided with a discharge hole 15 serving as a flow path through which the refrigerant flows from the compression chamber 9 to the discharge space 20 . A check valve 21 is provided at the outlet end of the discharge hole 15 to prevent the refrigerant from flowing back from the discharge space 20 to the compression chamber 9 . A discharge pipe 3 for discharging the refrigerant to the outside of the compressor 101 is provided in the discharge space 20 . A centrifugal separator 60 (hereinafter also referred to as an oil separator) 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 is passes through the centrifugal separation section 60 and is discharged from the discharge pipe 3 to the outside of the compressor 101 . An oil collecting portion 20a is provided outside the centrifugal separation portion 60, and the oil separated in the centrifugal separation portion 60 is collected in the oil collecting portion 20a. The frame 4 is fixed to the inner surface of the side container 1b by shrink fitting or the like. Further, in FIG. 1, the frame 4 is provided with a lateral hole (not shown) extending in the horizontal direction, but the frame 4 may not be provided with the lateral hole.

The centrifugal separation unit 60 includes a cylindrical portion 23 having a plurality of holes 23a (see FIG. 3, which will be described later) on the side wall, and a refrigerant flow discharged from the discharge hole 15, which flows in the circumferential direction of the cylindrical portion 23 by changing the direction of the flow. A swirling mechanism 22 is provided for causing a swirling flow in the cylindrical portion 23 by causing the water to flow. Also, the discharge pipe 3 is arranged so as to be positioned on the central axis of the cylindrical portion 23 .

The compression space 25 is provided with a helical passage screw 51 (hereinafter also referred to as a decompression portion or pressure loss portion), and the suction space 19 is provided with an oil return pipe 24 (hereinafter also referred to as an oil return portion). . The helical passage screw 51 and the oil return pipe 24 form an oil return flow path from the oil collection portion 20a to the oil storage portion 16. As shown in FIG. Details of the spiral passage screw 51 and the oil return pipe 24 will be described later. When the fixed scroll 8 is viewed from the upper side (discharge side), in addition to the spiral passage screw 51, a fastening bolt (not shown) that fastens the fixed scroll 8 and the frame 4 is the fixed base of the fixed scroll 8. A plurality of them are provided along the outer periphery of a plate (not shown). The fastening bolt is for screwing together and fixing both the fixed scroll 8 and the frame 4, and is completely different from the helical passage screw 51. As shown in FIG.

FIG. 2 is a perspective view of the turning mechanism section 22 in the centrifugal separation section 60 of the compressor 101 according to Embodiment 1. FIG. The dotted arrows in FIG. 2 indicate the flow of refrigerant and oil inside the swirling mechanism 22 .

The swirl mechanism part 22 is arranged to cover the discharge hole 15 and the check valve 21, and changes the direction of the refrigerant and oil discharged from the discharge hole 15 and the check valve 21 so as to generate a swirling flow. , a spiral flow path 22a is formed. A blowout port 22b for blowing out the refrigerant and oil in the circumferential direction of the cylindrical portion 23 is provided at the end of the spiral flow path 22a.

FIG. 3 is a perspective view of the cylindrical section 23 in the centrifugal separation section 60 of the compressor 101 according to Embodiment 1. FIG. The solid line arrows in FIG. 3 indicate the flow of refrigerant, and the dotted line arrows in FIG. 3 indicate the flow of oil.

The cylindrical portion 23 is provided with the swirl mechanism portion 22 inside thereof so that a swirl flow is formed inside the cylindrical portion 23 . A side wall of the cylindrical portion 23 is provided with a plurality of holes 23a for discharging the oil separated from the refrigerant by the centrifugal force of the swirling flow to the oil collecting portion 20a outside the cylindrical portion 23. As shown in FIG. A discharge pipe 3 for discharging the oil-separated refrigerant to the outside of the compressor 101 is arranged above the cylindrical portion 23 .

FIG. 4 is a cross-sectional view of the helical passage screw 51, the oil return pipe 24, and the surroundings of the compressor 101 according to the first embodiment.

A fixed scroll oil return pipe hole 81 is formed on the side of the fixed scroll 8 . The fixed scroll oil return pipe hole 81 includes a fixed scroll oil return pipe upper hole 8f formed in the upper portion of the fixed scroll 8, a fixed scroll oil return pipe lower hole 8d formed in the lower portion of the fixed scroll 8, and a fixed scroll oil return pipe lower hole 8d formed in the lower portion of the fixed scroll oil. A fixed scroll oil return pipe middle hole 8e is formed between the return pipe upper hole 8f and the fixed scroll oil return pipe lower hole 8d and communicates with them, and a fixed scroll oil return bypass hole 8g, which will be described later, is provided. .

A frame oil return pipe hole 82 is formed in the side portion of the frame 4 . The frame oil return pipe hole 82 includes a frame oil return pipe upper hole 4a formed in the upper portion of the frame 4, a frame oil return pipe lower hole 4c formed in the lower portion of the frame 4, and a frame oil return pipe upper hole 4a. It is formed between the frame oil return pipe lower hole 4c and the frame oil return pipe middle hole 4b communicating therewith.

The spiral passage screw 51 is a rod-shaped member provided inside the frame oil return pipe middle hole 4b and inserted from the fixed scroll oil return pipe upper hole 8f toward the frame oil return pipe lower hole 4c. The helical passage screw 51 has a body portion 51a, a small diameter portion 51b, a threaded portion 51c and a head portion 51d. The main body portion 51a is formed of a cylindrical rod-like body, and a spiral groove having a width (length in the vertical direction in FIG. 4) of about 0.5 to 1.0 mm is formed on the outer peripheral portion. The longer the axial length of the spiral groove of the body portion 51a, the better. The diameter of the body portion 51a<the diameter of the screw portion of the fastening bolt. Here, the frame 4 corresponding to the main body portion 51a formed with the spiral groove is a cylindrical long hole having no screw structure. A small gap is kept between them to prevent oil from flowing in the axial direction. Therefore, the oil slowly falls downward along the spiral grooves of the main body portion 51a. The small diameter portion 51b is formed to have a smaller diameter than the fixed scroll oil return pipe middle hole 8e, and forms an annular passage inside the fixed scroll oil return pipe middle hole 8e. In the first embodiment, the small-diameter portion 51b is formed inside the fixed scroll oil return pipe middle hole 8e. It may be an external thread formed in the The threaded portion 51c is formed of a cylindrical rod-like body, and has a male thread corresponding to a female thread formed at the upper end of the outer peripheral portion of the fixed scroll oil return pipe middle hole 8e. and fixed. The head 51d is formed in a disc shape having a diameter larger than that of the fixed scroll oil return pipe middle hole 8e.

The helical passage screw 51 increases the surface area that the oil contacts when passing through it, thereby increasing the pressure loss. The increase in pressure loss decompresses and cools the oil. Further, since the spiral passage screw 51 is provided inside the frame oil return pipe middle hole 4b, it is possible to save space compared to providing it outside the frame oil return pipe middle hole 4b.

The fixed scroll oil return pipe upper hole 8f is closed by the head 51d of the spiral passage screw 51, and the male thread of the threaded portion 51c is screwed into and fixed to the internal thread of the fixed scroll oil return pipe middle hole 8e. Therefore, the oil collected by the oil collecting portion 20 a does not flow from the upper side of the spiral passage screw 51 . Therefore, a fixed scroll oil return bypass hole 8g bypassing from the oil collecting portion 20a to the small diameter portion 51b of the helical passage screw 51 is provided obliquely on the side of the fixed scroll 8 as a flow path for the oil collected by the oil collecting portion 20a. is provided. The oil collected by the oil collecting portion 20a flows from the fixed scroll oil return bypass hole 8g (hereinafter also referred to as an oblique hole) through the small diameter portion 51b of the spiral passage screw 51 into the spiral groove of the main body portion 51a. supplied. That is, the oil collected by the oil collection portion 20a flows obliquely above the spiral passage screw 51 and is supplied to the spiral groove of the main body portion 51a through the fixed scroll oil return bypass hole 8g.

It is more desirable that the fixed scroll oil return bypass hole 8g satisfies the following three conditions in order to increase the pressure reduction and cooling effect. Although it is desirable to satisfy all three conditions, if at least one condition is satisfied, the decompression and cooling effects can be enhanced.

First condition: the direction in which the fixed scroll oil return bypass hole 8g extends is along the direction in which the spiral groove of the body portion 51a extends (that is, not in the opposite direction). Second condition: Angle α of the fixed scroll oil return bypass hole 8g with respect to the horizontal direction>Angle β of the spiral groove of the main body portion 51a with respect to the horizontal direction. Third condition: diameter of fixed scroll oil return bypass hole 8g>width of spiral groove of body portion 51a.

In FIG. 4, the oil return space A is formed on the right side of the spiral passage screw 51, but in Embodiment 1, oil does not flow from the upper side of the spiral passage screw 51, and this oil return space A is filled with oil. This oil return space A may not be formed because the oil does not flow.

The oil return pipe 24 is a circular pipe provided so as to extend from the lower portion (outlet side) of the spiral passage screw 51 toward the oil storage portion 16 . The spiral passage screw 51 and the oil return pipe 24 are in communication. It should be noted that the oil return pipe 24 may not be a simple circular hole as shown in FIG. Moreover, the oil return pipe 24 is not limited to a pipe, and may be a plate-like wall that forms an oil return space together with the inner wall of the container 1 . The spiral passage screw 51 is arranged on the upstream side of the oil return pipe 24 and fixed in the order of the spiral passage screw 51 and the oil return pipe 24 from the upstream side. Further, the spiral passage screw 51 and the oil return pipe 24 communicate with the fixed scroll oil return bypass hole 8g. Thus, the fixed scroll oil return bypass hole 8g, the helical passage screw 51, and the oil return pipe 24 form an oil return flow path from the oil collection portion 20a to the oil storage portion 16. As shown in FIG.

Hereinafter, the direction away from the compression mechanism 30 along the axial direction of the rotating shaft 5 with respect to the check valve 21 that discharges the refrigerant gas is defined as "up", and the opposite direction is defined as "down". . Looking at the height in the axial direction with reference to the position of the check valve 21 , the cylindrical portion 23 is at a higher position than the turning mechanism portion 22 and extends close to the inlet of the discharge pipe 3 . The lower end of the cylindrical portion 23 is tightly connected to the upper surface of the frame 4 without a gap.

There are no holes 23a in the lower region of the cylindrical portion 23, and the upper region, which is the upper region of the lower region, has a plurality of holes 23a. Moreover, the hole 23a is not formed at the height at which the swirling mechanism 22 blows out the refrigerant, that is, at the height at which the swirling flow starts to occur, but is formed just above it. The distance from the height of the outlet 22b of the turning mechanism 22 to the lower end of the area where the holes 23a are formed, that is, the height of the lowest hole 23a is preferably smaller than the height of the turning mechanism 22. Also, the height of the region in which the plurality of holes 23a are formed is desirably larger than the height of the turning mechanism 22, for example, 2 to 5 times. Moreover, it is preferable that the opening ratio of the region having the plurality of holes 23a in the side surface of the cylindrical portion 23 is, for example, less than 50%. This is because if the opening ratio is too high, a large amount of refrigerant gas leaks to the outside of the cylindrical portion 23 through the holes 23a, and a stable swirling flow may not be formed inside the cylindrical portion 23.

As shown in FIG. 1, the oil collecting portion 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 fixed scroll 8. It is provided outside the portion 60 . The oil discharged from the plurality of holes 23a of the cylindrical portion 23 of the centrifugal separation portion 60 is collected in the oil collecting portion 20a. The lower surface of the oil collecting portion 20a functions as an oil receiving surface that receives and temporarily holds the oil discharged from the centrifugal separation portion 60 to the oil collecting portion 20a and collected downward by gravity.

As shown in FIG. 1, a fixed scroll oil return bypass hole is provided as an oil return flow path for returning the oil discharged from the centrifugal separation unit 60 and collected in the oil collection unit 20a to the oil storage unit 16 of the suction space 19. 8g, a helical passage screw 51 and an oil return pipe 24 are provided in the compression space 25 and the suction space 19. As shown in FIG. Due to the pressure difference between the discharge space 20 and the suction space 19, the oil collected in the oil collecting portion 20a flows to the oil storage portion 16 on the suction space 19 side together with a part of the refrigerant.

The fixed scroll oil return bypass hole 8g is arranged so that the oil collected in the oil collecting portion 20a and flowed by gravity and collected at a low position of the oil collecting portion 20a flows into the fixed scroll oil return bypass hole 8g. It is preferably arranged at a position lower than the portion 20 a , preferably lower than the upper surface of the fixed scroll 8 . In addition, the diameters of the fixed scroll oil return bypass hole 8g, the spiral passage screw 51, and the internal flow path of the oil return pipe 24 are sized to allow the oil to smoothly flow to the oil storage portion 16 without accumulating too much in the oil collection portion 20a. should be adjusted to In addition, the diameters of the internal flow paths of the fixed scroll oil return bypass hole 8g, the spiral passage screw 51, and the oil return pipe 24 pass through the fixed scroll oil return bypass hole 8g, the spiral passage screw 51, and the oil return pipe 24. It is preferable that the size is adjusted so that the amount of refrigerant flowing from the discharge space 20 to the suction space 19 side is not too large and the compression efficiency or the volumetric efficiency is not lowered. In addition, the fixed scroll oil return bypass hole 8g, the helical passage screw 51, and the oil return pipe 24 pass through the oil supply pipe 13 on the way from the oil collection portion 20a to the oil storage portion 16 and the power conversion mechanism portion 6. It may merge with the oil flow path after lubrication, and the oil may be discharged to the suction space 19 .

In order to lubricate the spiral wrap 7a of the orbiting scroll 7 and the spiral wrap 8a of the fixed scroll 8, the frame 4 or the fixed scroll 8 is provided with oil supplied to the power conversion mechanism 6 through the oil supply pipe 13. A passage (not shown) may be provided for circulating part of the gas to the suction hole 14 or the compression chamber 9 .

In the compressor 101 configured as described above, when the electric mechanism portion 40 is energized, a torque is applied to the rotor 11 to rotate the rotating shaft 5 and the orbiting scroll 7 is orbiting relative to the fixed scroll 8. exercise. Thereby, the refrigerant is compressed in the compression chamber 9 . In the process, part of the oil droplets contained in the refrigerant in the suction space 19 or part of the oil flowing through the oil supply pipe 13 to the power conversion mechanism 6 is released into the suction hole together with the refrigerant. 14 into the compression chamber 9 .

The refrigerant containing oil that has flowed into the compression chamber 9 is compressed, passes through the discharge hole 15 and the check valve 21, and flows into the swirl mechanism section 22 of the centrifugal separation section 60. Further, the oil that has flowed into the compression chamber 9 lubricates the spiral wrap 7a of the orbiting scroll 7 and the spiral wrap 8a of the fixed scroll 8, and flows into the swirl mechanism portion 22 together with the refrigerant. In the swirl mechanism portion 22, the refrigerant and the oil turn into a swirling flow and flow into the cylindrical portion 23, where the refrigerant and the oil are separated by the centrifugal force of the swirling flow. Most of the refrigerant separated from the oil rises while swirling inside the cylindrical portion 23 and is discharged from the discharge pipe 3 to the outside of the compressor 101 . On the other hand, the oil separated from the refrigerant 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 through the fixed scroll oil return bypass hole 8g and the spiral passage screw 51. , and through the oil return pipe 24 from the high pressure space towards the low pressure space to the oil reservoir 16 .

More specifically, the swirling mechanism 22 generates a swirling flow in the lower portion of the cylindrical portion 23 . The generated swirling flow rises while flowing along the inner wall surface of the cylindrical portion 23 , and is eventually discharged out of the container 1 through the discharge pipe 3 near the center of the cylindrical portion 23 . Inside the cylindrical portion 23, the swirling flow causes a strong centrifugal force to act on the oil, which is denser than the refrigerant gas, that is, the oil droplets and oil mist contained in the refrigerant gas, causing the oil to fly toward the inner wall of the cylindrical portion 23. will come to A portion of the oil is directly discharged out of the cylindrical portion 23 through the direct holes 23a, and the remaining oil adheres to the inner wall surface of the cylindrical portion 23 and forms an oil film. Since the swirling flow of the refrigerant gas flows just inside this oil film, the oil film is pushed by the flow and flows to the position of the hole 23a. Then, the oil film is again separated from the edge of the hole 23a by the centrifugal force at the position of the edge of the hole 23a, or pushed out of the cylindrical portion 23 along the inner surface of the hole 23a. In this way, the oil separated from the refrigerant is discharged from the plurality of holes 23 a provided in the cylindrical portion 23 to the oil collecting portion 20 a outside the cylindrical portion 23 .

The oil discharged to the oil collecting portion 20a drops by gravity or adheres to the outer wall surface of the cylindrical portion 23 or the inner wall surface of the upper container 1a and then flows by gravity and is fixed to the lower surface of the oil collecting portion 20a. They gather on the upper surface of the scroll 8. Due to gravity and the pressure difference between the discharge space 20 and the suction space 19, the oil collected on the upper surface of the fixed scroll 8 flows along with some refrigerant through the fixed scroll oil return bypass hole 8g, the spiral passage screw 51, and the oil return pipe 24. It flows and is discharged into the suction space 19 . A portion of the oil discharged to the suction space 19 becomes oil droplets and flows through the suction hole 14 and into the compression chamber 9 again, but most of it flows downward to the oil storage portion 16 due to gravity.

In the compressor 101 according to the first embodiment, the oil adhered to the inner wall surface of the cylindrical portion 23 due to the centrifugal force of the swirling flow in the centrifugal separation portion 60 is removed from the plurality of holes 23a formed in the wall surface of the cylindrical portion 23. The oil is quickly discharged to the oil collecting portion 20a outside the portion 23. In this way, by discharging the oil to the oil collecting portion 20a and separating it from the swirling flow inside the cylindrical portion 23, it is possible to suppress the oil adhering to the inner wall surface of the cylindrical portion 23 from being swirled up by the swirling flow and being scattered. be done. As a result, the amount of oil discharged from the discharge pipe 3 to the outside of the compressor 101 can be greatly reduced. Further, even in a compressor 101 having a low height of the centrifugal separation unit 60, such as having the centrifugal separation unit 60 inside the compressor 101, the amount of oil discharged to the outside of the compressor 101 can be sufficiently reduced. It becomes possible.

Further, the lower end of the cylindrical portion 23 is connected to the lower surface of the oil collecting portion 20a without a gap, and a hole 23a is formed in a lower region of the side surface of the cylindrical portion 23 adjacent to the lower end of the cylindrical portion 23. preferably not. In other words, it is preferable that the hole 23a is not formed up to a certain height from the lower end of the cylindrical portion 23. As shown in FIG. For example, it is preferable that the hole 23a is not formed below the height of the outlet 22b of the swivel mechanism 22 . As a result, the lower region of the side wall of the cylindrical portion 23 serves as a partition, thereby suppressing the oil collected on the lower surface of the oil collecting portion 20 a from entering the cylindrical portion 23 .

In addition, in the lower region, the swirling flow inside the cylindrical portion 23 does not blow out to the outside of the cylindrical portion 23, so that the oil collected on the lower surface of the oil collecting portion 20a is prevented from being swirled up. As a result, the amount of oil discharged out of the compressor 101 can be further reduced. Inside the cylindrical portion 23, the oil adhering to the inner wall surface of the lower cylindrical portion 23 where the hole 23a is not formed or the bottom surface of the cylindrical portion 23 is removed from the cylindrical portion 23 by the refrigerant gas flow that rises while swirling. It is pushed up to the hole 23a along the inner wall surface and pushed out of the cylindrical portion 23 from the hole 23a. 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 22b of the turning mechanism portion 22. As a result, the refrigerant gas ejected from the outlet 22b of the swirl mechanism portion 22 can reliably flow along the inner wall surface of the cylindrical portion 23 to form a strong and stable swirl flow. The “same” height does not have to be exactly the same, but means that the height is substantially the same to the extent that the refrigerant gas ejected from the outlet 22b of the turning mechanism 22 hits directly. ing.

In addition, the strength of the swirling flow is strongest immediately after exiting from the outlet 22b of the swirling mechanism 22, and tends to weaken as it rises from the outlet 22b of the swirling mechanism 22 toward the discharge pipe 3. For this reason, if there is a region in which the holes 23a are formed at a height just above the outlet 22b of the turning mechanism 22, the oil can be discharged out of the cylindrical portion 23 more efficiently. For example, the distance from the height of the outlet 22b of the turning mechanism 22 to the lower end of the area where the holes 23a are formed, that is, the height of the hole 23a at the bottom, should be smaller than the height of the turning mechanism 22. .

In addition, in the region of the side surface of the cylindrical portion 23 where the plurality of holes 23a are formed, the ratio of the total opening area of the holes 23a in that region is preferably less than 50%, for example. If the ratio of the opening area of the hole 23a is too large, the amount of refrigerant leaking through the hole 23a to the outside of the cylindrical portion 23 increases, and the amount of refrigerant inside the cylindrical portion 23 decreases, weakening the swirling flow and causing the oil to leak. Separation efficiency may decrease. By reducing the ratio of the opening area, the amount of refrigerant that leaks out of the cylindrical portion 23 through the holes 23a can be reduced, and a strong swirling flow can be formed inside the cylindrical portion 23. FIG.

Further, in Embodiment 1, even when the compressor 101 is started from a state in which a large amount of liquefied refrigerant has accumulated, the amount of oil discharged from the compressor 101 can be reduced. When the compressor 101 is stopped, the refrigerant gas inside the compressor 101 may be liquefied, and a large amount of the liquefied refrigerant may accumulate in the suction space 19 inside the compressor 101 . When the compressor 101 is started from this state, a large amount of oil flows into the compression chamber 9 through the suction hole 14 due to bubbling of the oil reservoir 16 due to rapid vaporization of the refrigerant or agitation by the rotor 11, and is discharged. It flows through the holes 15 into the discharge space 20 . At this time, if the return of the oil to the oil storage portion 16 through the oil return passage cannot catch up, the oil will temporarily accumulate in the discharge space 20 .

In Embodiment 1, a large amount of oil that has flowed into the discharge space 20 is discharged through the plurality of holes 23a to the wide oil collecting portion 20a outside the cylindrical portion 23 and accumulated therein. Therefore, a large amount of oil is not continuously exposed to the violent swirling flow of the refrigerant inside the cylindrical portion 23 and the oil surface is not swirled up. In particular, the lower portion of the cylindrical portion 23 is connected to the upper surface of the fixed scroll 8 corresponding to the lower surface of the oil collecting portion 20a without any gap, and the side wall of the cylindrical portion 23 has no hole 23a in the lower region. For this reason, this portion acts as a partition to prevent the oil held in the oil collecting portion 20a outside the cylindrical portion 23 from entering the inside of the cylindrical portion 23. As shown in FIG. In addition, since the swirling flow inside the cylindrical portion 23 does not flow out from the lower portion of the cylindrical portion 23 to the outside of the cylindrical portion 23, it is possible to prevent the oil accumulated in the low position of the oil collecting portion 20a from being swirled up.

After that, as the bubbling of the oil storage portion 16 or the agitation by the rotor 11 subsides and the amount of oil flowing into the discharge space 20 decreases and returns to normal, the oil accumulated in the oil collecting portion 20a gradually returns to the fixed scroll oil. It flows through the bypass hole 8g, the helical passage screw 51, and 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 startup, the amount of oil discharged to the outside of the compressor 101 can be reduced.

Further, in Embodiment 1, the refrigerant compressed in the compression chamber 9 flows through the discharge hole 15 and immediately flows into the swirling mechanism portion 22 to form a swirling flow, and then rises while swirling inside the cylindrical portion 23 . It is discharged to the outside of the compressor 101 through the discharge pipe 3 . For this reason, bending, sudden expansion, and sudden contraction of the flow path can be minimized. Therefore, the pressure loss becomes small, and the deterioration of the compression efficiency is suppressed.

Also, Embodiment 1 can reduce noise generated during operation of the compressor 101 . A discharge space 20 of the compressor 101 is separated into an outer space and an inner space by a cylindrical portion 23, and both spaces communicate with each other through a plurality of holes 23a. This structure is a resonance type muffling structure, and can greatly reduce noise in a specific frequency band in particular. In the compressor 101 according to Embodiment 1, 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 are adjusted to reduce noise in the frequency band desired to be reduced. may be adjusted.

In the compressor 101 configured in this way, the amount of oil discharged outside the compressor 101 can be reduced by separating the oil by the centrifugal separation section 60, and cost and space can be reduced.

In Embodiment 1, the refrigerant and oil flowing into the centrifugal separation section 60 of the discharge space 20 are separated by centrifugation, but the configuration is not limited to this as long as the oil can be separated from the refrigerant.

As described above, the compressor 101 according to Embodiment 1 includes the container 1 having the oil storage portion 16, the suction pipe 2 for sucking the refrigerant from the outside of the container 1, and the suction pipe 2 is arranged inside the container 1 to suck the refrigerant. A compression mechanism portion 30 for compressing the refrigerant, a frame 4 for fixing the compression mechanism portion 30 to the container 1, an oil separation portion for separating oil from the refrigerant compressed by the compression mechanism portion 30, and a refrigerant passing through the oil separation portion. to the outside from the upper part of the container 1, an oil collection part 20a provided outside the oil separation part and collecting the oil discharged from the oil separation part, and the oil collected in the oil collection part 20a to the oil storage unit 16, and the oil return flow path is configured, and is provided to extend from the outlet side of the pressure reduction unit toward the oil storage unit 16, and after passing through the pressure reduction unit and an oil return section for returning the oil to the oil storage section 16 .

According to the compressor 101 according to Embodiment 1, the pressure reducing section configuring the oil return flow path for returning the oil collected in the oil collecting section 20 a to the oil storage section 16 is provided. Thus, by providing the pressure reducing portion in the oil return passage for returning the oil collected in the oil collecting portion 20a to the oil storage portion 16, the pressure loss of the oil increases when passing through the pressure reducing portion. Since the oil collected in the oil collecting portion 20a can be decompressed and cooled due to the increase in pressure loss, the high-pressure and high-temperature oil collected in the oil collecting portion 20a can be returned to the oil storage portion 16 as it is. Therefore, it is possible to suppress a decrease in reliability.

Further, the compressor 101 according to Embodiment 1 has an oblique hole that forms an oil return flow path and supplies the oil collected in the oil collecting portion 20a from obliquely above to the pressure reducing portion.

According to the compressor 101 according to Embodiment 1, even if the upper flow path of the decompression section is blocked, the oblique holes supply the oil collected in the oil collecting section 20a obliquely from above to the decompression section. can do.

Further, in the compressor 101 according to Embodiment 1, the direction in which the oblique holes extend is along the direction in which the spiral grooves of the main body portion 51a extend. Further, the angle of the oblique hole with respect to the horizontal direction is larger than the angle of the spiral groove of the main body portion 51a with respect to the horizontal direction. Moreover, the diameter of the oblique hole is larger than the width of the spiral groove of the body portion 51a.

According to the compressor 101 according to Embodiment 1, by satisfying at least one of the above three conditions, the decompression and cooling effects can be enhanced.

Further, in the compressor 101 according to Embodiment 1, the side surface of the frame 4 is formed with a frame oil return pipe hole 82 through which the oil collected in the oil collection portion 20a flows, and the decompression portion serves as a frame oil return pipe hole 82. It is provided inside the tube hole 82 .

According to the compressor 101 according to Embodiment 1, since the decompression part is provided inside the frame oil return pipe hole 82, the space can be saved more than if it is provided outside the frame oil return pipe hole 82. can be done.

Also, the compressor 101 according to Embodiment 1 uses an HFC-based refrigerant, an HC-based refrigerant, or a natural refrigerant as a refrigerant.

According to the compressor 101 according to Embodiment 1, an HFC-based refrigerant, an HC-based refrigerant, or a natural refrigerant is used as a refrigerant, and these refrigerants have a low global warming potential (GWP). can reduce the impact on

FIG. 5 is a schematic cross-sectional view of the internally grooved copper tube 52 .
In Embodiment 1, the spiral passage screw 51 is provided as a structure for decompressing and cooling the oil separated by the centrifugal separation section 60, but the structure is not limited to this. Instead of the helical passage screw 51, for example, a capillary tube or an internally grooved copper tube 52 shown in FIG. However, when these are provided, in order to decompress and cool the oil to the same extent as the spiral passage screw 51, the pipe length must be longer than when the spiral passage screw 51 is provided, so the spiral passage screw 51 is preferable. The same effect can be obtained in a space-saving manner.

Embodiment 2.
The second embodiment will be described below, focusing on the differences between the second embodiment and the first embodiment.

FIG. 6 is a schematic cross-sectional view showing the configuration of a compressor 101a according to Embodiment 2. FIG. The dotted arrows in FIG. 6 indicate the main flow of oil.

As shown in FIG. 6, the compressor 101a according to the second embodiment is a horizontal type that is installed sideways so that the rotating shaft 5 is inclined with respect to the direction of gravity or the rotating shaft 5 is horizontal. Compressor. As the inclination of the rotating shaft 5 with respect to the direction of gravity approaches horizontal, the oil storage section 16 is disposed downward toward the side container 1b due to gravity. Therefore, the oil supply pipe 17 has a structure extending toward the oil storage portion 16 on the lower side in the gravity direction so that the suction port 17a is immersed in the oil in the oil storage portion 16 . Furthermore, the oil discharged from the plurality of holes 23a of the cylindrical portion 23 into the discharge space 20 outside the cylindrical portion 23 is gathered in the lower oil collecting portion 20a by gravity. Therefore, the end portion of the spiral passage screw 51 on the side of the discharge space 20 is formed on the outer peripheral portion of the frame 4 on the side of the side container 1b, which is the lower side in the direction of gravity. A fixed scroll oil return bypass hole 8g that bypasses the helical passage screw 51 from the oil collecting portion 20a is provided in the side portion of the fixed scroll 8 on the lower side in the direction of gravity. That is, the upper opening of the fixed scroll oil return bypass hole 8g and the suction port 17a of the oil supply pipe 17, which serve as the inlet of the oil return flow path, are provided on the lower side in the direction of gravity when installed horizontally.

As in the example shown in the first embodiment, the refrigerant and oil that have flowed out to the centrifugal separation section 60 of the discharge space 20 through the discharge hole 15 and the check valve 21 in this order form a swirling flow in the swirling mechanism section 22. , the centrifugal force of the swirling flow in the cylindrical portion 23 separates the refrigerant and the oil. After that, the refrigerant is discharged outside the compressor 101 through the discharge pipe 3 , and the oil is discharged from the plurality of holes 23 a of the cylindrical portion 23 to the discharge space 20 outside the cylindrical portion 23 . The oil discharged into the discharge space 20 outside the cylindrical portion 23 flows downward through the discharge space 20 as it is due to gravity drop, or flows downward on the surface of the fixed scroll 8 or the bottomed cylindrical upper container 1a of the container 1. It adheres and flows below the discharge space 20 along its surface. Oil collected in the oil collecting portion 20a below the discharge space 20 flows through the fixed scroll oil return bypass hole 8g, the spiral passage screw 51, and the oil return pipe 24 due to the pressure difference between the discharge space 20 and the suction space 19. and discharged into the suction space 19 . A portion of the oil discharged to the suction space 19 becomes oil droplets and flows through the suction hole 14 and into the compression chamber 9 again, but most of it flows downward to the oil storage portion 16 due to gravity.

In this way, the oil is not collected inside the cylindrical portion 23, but is collected in the discharge space 20 outside the cylindrical portion 23 and is discharged to the suction space 19. Therefore, even in the horizontal type compressor 101a in which the rotating shaft 5 is inclined with respect to the direction of gravity, the oil adhering to the inner wall surface of the cylindrical portion 23 is prevented from being swirled up by the swirling flow and being scattered. The amount of oil discharged from the machine 101a can be greatly reduced.

In the compressor 101a, when the compressor 101a is installed horizontally, the upper opening of the fixed scroll oil return bypass hole 8g serving as the inlet of the oil return passage is provided on the lower side in the direction of gravity. The oil accumulated in the oil collecting portion 20a is discharged from the inlet of the oil return passage to the suction space 19 through the spiral passage screw 51 and the oil return pipe 24. - 特許庁Furthermore, in the compressor 101a, when the compressor 101a is installed horizontally, the suction port 17a of the oil supply pipe 17 is provided on the lower side in the direction of gravity. The oil is pumped up from 17a by an oil pump 18 and supplied to each sliding portion in the compressor 101a through an oil supply pipe line 13 formed inside the rotating shaft 5. As shown in FIG. Therefore, even if the compressor 101a is installed horizontally, the oil will accumulate in the oil collecting portion 20a of the discharge space 20 or the oil storage portion 16 of the suction space 19, and the oil supplied to the sliding portion will be depleted. It is possible to suppress a decrease in reliability due to In addition, it is possible to install the horizontal compressor 101a even when the installation space is low and it is difficult to install the vertical compressor 101a.

As described above, the compressor 101a according to the second embodiment includes the electric mechanism portion 40 that drives the compression mechanism portion 30, and the rotation shaft 5 that receives the rotational driving force of the electric mechanism portion 40 and transmits it to the compression mechanism portion 30. It is a horizontal type in which the rotating shaft 5 is inclined with respect to the direction of gravity or is installed horizontally so that the rotating shaft 5 is horizontal. An oil pump 18 is provided for pumping up the accumulated oil, and an oil supply pipe 17 extending toward the oil reservoir 16 is connected to the oil pump 18. When the oil pump 18 is installed sideways, the oil return flow path is closed. The suction port 17a formed at the inlet and the tip of the oil supply pipe 17 is provided on the lower side in the direction of gravity.

According to the compressor 101a according to the second embodiment, when the compressor 101a is installed sideways, the suction port 17a formed at the inlet of the oil return passage and the tip of the oil supply pipe 17 is provided at the lower side in the direction of gravity. It is Therefore, the oil accumulated in the oil collecting portion 20a below the discharge space 20 is discharged from the inlet of the oil return passage through the spiral passage screw 51 and the oil return pipe 24 to the oil storage portion 16. Further, the oil in the oil storage portion 16 is pumped up by the oil pump 18 from the suction port 17a, and supplied to each sliding portion in the compressor 101a. Therefore, even if the compressor 101a is installed horizontally, the oil will accumulate in the oil collecting portion 20a of the discharge space 20 or the oil storage portion 16 of the suction space 19, and the oil supplied to the sliding portion will be depleted. It is possible to suppress a decrease in reliability due to In addition, it is possible to install the horizontal compressor 101a even when the installation space is low and it is difficult to install the vertical compressor 101a.

Embodiment 3.
The third embodiment will be described below, focusing on the differences of the third embodiment from the first and second embodiments.

FIG. 7 is a diagram showing a configuration example of a refrigeration cycle apparatus according to Embodiment 3. FIG. Note that FIG. 7 shows an air conditioner as the refrigeration cycle device. Further, the solid line arrows in FIG. 7 indicate the flow of the refrigerant during the cooling operation, and the broken line arrows indicate the flow during the heating operation.

In the air conditioner shown in FIG. 7, an outdoor unit 100 and an indoor unit 200 are connected by gas refrigerant piping 300 and liquid refrigerant piping 400 to form a refrigerant circuit for circulating the refrigerant. The outdoor unit 100 has the compressor 101 described in the first embodiment. The air conditioner may have the compressor 101a described in the second embodiment instead of the compressor 101 described in the first embodiment. In addition, the outdoor unit 100 has a channel switching device 102 , an outdoor heat exchanger 103 and an expansion device 104 . Also, the indoor unit 200 has an indoor heat exchanger 201 .

The compressor 101 compresses and discharges the sucked refrigerant. Here, although not particularly limited, the compressor 101 may be configured so that the operating frequency can be arbitrarily changed by, for example, an inverter circuit or the like.

The channel switching device 102 is, for example, a four-way valve, and switches between the cooling operation and the heating operation by switching the flow direction of the refrigerant. As the channel switching device 102, a combination of a two-way valve and a three-way valve may be used instead of the four-way valve.

The outdoor heat exchanger 103 exchanges heat between refrigerant and air (outdoor air). For example, during heating operation, it functions as an evaporator to evaporate and vaporize the refrigerant. Also, during cooling operation, it functions as a condenser to condense and liquefy the refrigerant.

The expansion device 104 reduces the pressure of the refrigerant to expand it. For example, when an electronic expansion valve or the like is used, the degree of opening is adjusted based on an instruction from a control device (not shown) or the like.

The indoor heat exchanger 201 performs heat exchange, for example, between the air to be air-conditioned and the refrigerant. During heating operation, it functions as a condenser to condense and liquefy the refrigerant. Also, during cooling operation, it functions as an evaporator to evaporate and vaporize the refrigerant.

As described above, according to the refrigeration cycle apparatus of Embodiment 3, the compressor 101 described in Embodiment 1 or the compressor 101a described in Embodiment 2 is provided as equipment. Therefore, the same effects as those of the compressor 101 described in the first embodiment or the compressor 101a described in the second embodiment can be obtained.

1 container, 1a upper container, 1b side container, 1c lower container, 2 suction pipe, 3 discharge pipe, 4 frame, 4a frame oil return pipe upper hole, 4b frame oil return pipe middle hole, 4c frame oil return pipe lower hole , 5 rotary shaft, 6 power conversion mechanism, 7 orbiting scroll, 7a spiral wrap, 8 fixed scroll, 8a spiral wrap, 8d fixed scroll oil return pipe pilot hole, 8e fixed scroll oil return pipe middle hole, 8f fixed scroll oil Return pipe upper hole 8g Fixed scroll oil return bypass hole 9 Compression chamber 10 Subframe 11 Rotor 12 Stator 13 Oil supply pipe 14 Suction hole 15 Discharge hole 16 Oil reservoir 17 Oil supply Pipe, 17a Suction port, 18 Oil pump, 19 Suction space, 20 Discharge space, 20a Oil collecting part, 21 Check valve, 22 Turning mechanism part, 22a Flow path, 22b Blowout port, 23 Cylindrical part, 23a Hole, 24 Oil Return pipe, 25 Compression space, 30 Compression mechanism, 40 Electric mechanism, 51 Spiral passage screw, 51a Main body, 51b Small diameter part, 51c Threaded part, 51d Head, 52 Inner grooved copper tube, 60 Centrifugal separator, 81 fixed scroll oil return pipe hole, 82 frame oil return pipe hole, 100 outdoor unit, 101 compressor, 101a compressor, 102 flow switching device, 103 outdoor heat exchanger, 104 expansion device, 200 indoor unit, 201 indoor heat Exchanger, 300 gas refrigerant piping, 400 liquid refrigerant piping.

Claims

a container having an oil reservoir;
a suction pipe for sucking refrigerant from the outside of the container;
a compression mechanism that is disposed inside the container and compresses the refrigerant sucked by the suction pipe;
a frame that fixes the compression mechanism to the container;
an oil separation unit that separates oil from the refrigerant compressed by the compression mechanism;
a discharge pipe that discharges the refrigerant that has passed through the oil separation unit to the outside from the upper part of the container;
an oil collection section provided outside the oil separation section for collecting the oil discharged from the oil separation section;
a decompression unit that forms an oil return passage for returning the oil collected in the oil collection unit to the oil storage unit;
an oil return portion that constitutes the oil return flow path, is provided so as to extend from the outlet side of the pressure reduction portion toward the oil storage portion, and returns oil after passing through the pressure reduction portion to the oil storage portion. ,
The decompression unit is
A compressor for increasing the pressure loss of the oil collected in the oil collecting section.
The decompression unit is
The compressor according to claim 1, which is a helical passage screw having a main body formed by a cylindrical rod body and having a helical groove formed on an outer peripheral portion thereof.
The compressor according to claim 2, further comprising an oblique hole that constitutes the oil return flow path and supplies the oil collected in the oil collecting portion to the pressure reducing portion from obliquely above.
The compressor according to claim 3, wherein the direction in which the oblique holes extend is along the direction in which the spiral grooves of the body portion extend.
The compressor according to claim 3 or 4, wherein the angle of the oblique hole with respect to the horizontal direction is larger than the angle of the spiral groove of the main body with respect to the horizontal direction.
The compressor according to any one of claims 3 to 5, wherein the diameter of the oblique hole is larger than the width of the spiral groove of the main body.
A frame oil return pipe hole is formed in the side surface of the frame through which the oil collected in the oil collecting portion flows,
The compressor according to any one of claims 1 to 6, wherein the decompression section is provided inside the frame oil return pipe hole.
The oil separation unit is
a cylindrical portion having a plurality of holes on its side surface for discharging oil to the oil collecting portion;
Provided inside the lower region of the cylindrical portion, by blowing out the refrigerant compressed by the compression mechanism portion, it flows toward the discharge pipe at the top of the container while rotating inside the cylindrical portion, and flows from the refrigerant. The compressor according to any one of Claims 1 to 7, further comprising a swirl mechanism portion that forms a swirl flow that separates the oil.
an electric mechanism unit that drives the compression mechanism unit;
a rotating shaft that receives the rotational driving force of the electric mechanism and transmits it to the compression mechanism;
A horizontal installation type in which the rotation axis is inclined with respect to the direction of gravity or is installed sideways so that the rotation axis is horizontal,
One end of the rotating shaft is provided with an oil pump for pumping up the oil accumulated in the oil reservoir,
An oil supply pipe extending toward the oil reservoir is connected to the oil pump,
When installed horizontally,
The compressor according to any one of claims 1 to 8, wherein the inlet of the oil return passage and the suction port formed at the tip of the oil supply pipe are provided on the lower side in the direction of gravity.
The compressor according to any one of claims 1 to 9, wherein an HFC refrigerant, an HC refrigerant, or a natural refrigerant is used as the refrigerant.
A refrigeration cycle apparatus having a refrigerant circuit in which the compressor, condenser, expansion device, and evaporator according to any one of claims 1 to 10 are connected by pipes and in which refrigerant circulates.